Contenido

La biodiversidad se define comúnmente como la variedad de vida en la Tierra en todas sus formas, incluida la diversidad de especies, sus variaciones genéticas y la interacción de estas formas de vida. Sin embargo, desde finales del siglo , la pérdida de biodiversidad causada por el comportamiento humano ha causado impactos más severos y duraderos.[17]​ Los principales científicos y el histórico Informe de Evaluación Global sobre Biodiversidad y Servicios de los Ecosistemas del IPBES afirman que el crecimiento de la población humana y el consumo excesivo son los factores principales de esta disminución en biodiversidad.[18]​[19]​[20]​[1]​[21]​ Los impulsores humanos de la pérdida de biodiversidad incluyen la alteración del hábitat, la contaminación y la sobreexplotación de los recursos naturales.[22]​.

Land use change

Examples of land use changes include deforestation, intensive monoculture, and urbanization.[41]​.

The 2019 IPBES Global Assessment Report on Biodiversity and Ecosystem Services states that industrial agriculture is the main driver of biodiversity collapse.[42]​[18]​ The UN's Global Biodiversity Outlook 2014 estimates that 70% of the projected loss of terrestrial biodiversity is caused by the use of agriculture. Additionally, more than a third of the planet's land surface is used for crops and livestock grazing.[43] Agriculture destroys biodiversity by converting natural habitats into intensively managed systems and by releasing pollutants, including greenhouse gases. Food value chains further amplify impacts, with this effect exacerbated through energy use, transportation, and waste.[44] The direct effects of urban growth on habitat loss have been well characterized: the construction of infrastructure often results in habitat destruction and fragmentation. Increased urbanization greatly reduces biodiversity when large areas of natural habitat are fragmented,[45]​ leading to altered species selection processes, causing many to adapt to urban environments or move away from these urbanized areas.[46]​ As large patches of disturbed soil grow, small patches of habitat cannot support the same level of genetic or taxonomic diversity as before, while some of the most sensitive species may become extinct. locally.[47]​ Species with abundant populations are reduced due to small fragmented areas, which causes an increase in the isolation of species and forces them to go to edge habitats and adapt to foraging elsewhere.[45]​ Human-caused habitat fragmentation tends to create barriers that hinder dispersal, preventing species from moving with their ideal niche as it shifts due to disturbances such as climate change.[48]​ Although The negative effects of fragmentation tend to be well known, the risk of fragmentation tends to have minor effects on biodiversity and can even change and strengthen certain relationships between species.[49]​.

According to a 2020 study published in Nature Sustainability, more than 17,000 species are at risk of losing their habitat by 2050 as agriculture continues to expand to meet future food needs. Researchers suggest that greater agricultural efficiency in developing countries as well as a large-scale population shift to plant-based diets could help reduce habitat loss.[50] Similarly, a Chatham report House also postulated that a global shift toward primarily plant-based diets would free up enough land to allow for the restoration of ecosystems and biodiversity, because in the 2010s more than 80% of all agricultural land in the world was used to raise animals.[51] A 2022 study published in Science concluded that at least 64 million square kilometers, 44% of the Earth's surface, require conservation attention (from protected areas to land use policies). soil) to ensure important zones of biodiversity, ecologically intact areas and optimal locations for the representation of species ranges and ecoregions.[52]​.

Pollution

Four commonly studied and monitored greenhouse gases are water vapor, carbon dioxide, methane, and nitrous oxide (nitrogen(I) oxide). Over the past 250 years, concentrations of carbon dioxide and methane have increased, along with the introduction of purely anthropogenic emissions such as hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride into the atmosphere.[53] These pollutants are emitted into the atmosphere by the burning of fossil fuels and biomass ("Biomass (energy)"), deforestation, and agricultural practices that amplify the effects of climate change.[54][55]​ As higher concentrations of greenhouse gases are released into the atmosphere, the Earth's surface temperature increases. This is because greenhouse gases are able to absorb, emit and trap heat from the Sun that enters the Earth's atmosphere.[53]​ With the increase in temperature expected from the increase in greenhouse gases, higher levels of air pollution, greater variability in weather patterns, intensification of the effects of climate change and changes in the distribution of vegetation in the landscape are predicted.[22][56]​.

Other pollutants released from industrial and agricultural activity include sulfur dioxide and nitrogen oxides.[53] Once sulfur dioxide and nitrogen oxide are introduced into the atmosphere, they can react with cloud droplets (cloud condensation nuclei), raindrops, or snowflakes, forming sulfuric acid and nitric acid. With the interaction between water droplets and sulfuric and nitric acids, "wet deposition" occurs and creates acid rain.[57]​[58]​ As a result, these acids would be displaced to various environments and vegetation during precipitation, having a significant aerial distance (hundreds of kilometers) from the emission source. Sulfur dioxide and nitrogen oxide can also be displaced over vegetation through dry deposition").[59]​.

The concentration of sulfur dioxide and nitrous oxide has many implications in aquatic ecosystems, including changing acidity, increasing nitrogen and aluminum content, and altering biogeochemical processes.[59] Generally, sulfur dioxide and nitrous oxide have no direct physiological effects after an organism is exposed to them; Most of the effects develop through accumulation and prolonged exposure of these gases in the environment, modifying the chemistry of soil and water.[59]​[60]​ Consequently, sulfur contributes greatly to the acidification of lakes and oceans, and nitrogen initiates the eutrophication of continental and coastal water bodies that lack nitrogen. Both phenomena alter the composition of the native aquatic biota and influence the original food web with a higher level of acidity, minimizing aquatic and marine biodiversity.[58][59]​.

Nitrogen deposition has also affected terrestrial ecosystems, including forests, grasslands, alpine regions and bogs.[59]​ Nitrogen input has altered the natural biogeochemical cycle and promoted soil acidification.[61]​ As a result, plant and animal species composition and ecosystem functionality are likely to decline due to increased soil sensitivity: contributing to slower forest growth, damage to trees at higher elevations. higher and leads to the replacement of native biota with nitrogen-loving species.[17]​[59]​ In addition, sulfate and nitrate can leach from the soil, removing essential nutrients such as calcium and magnesium, and deposit in freshwater, coastal and oceanic environments, promoting eutrophication.[59]​.

Invasive species

Invasive species have important implications for biodiversity loss as they have degraded various ecosystems around the world. Invasive species are migratory species that have outcompeted and displaced native species, altered species richness and food webs, and changed ecosystem functions and services.[74]​[75]​ Invasive species are introduced into a new habitat, whether intentionally or unintentionally, by human activities. The most common methods for introducing aquatic invasive species are by ballast water, on ship hulls, and attached to equipment such as fishing nets.[76]​ According to the Millennium Ecosystem Assessment, invasive species are considered one of the top five drivers of biodiversity loss.[77]​ Over the past half century, biological invasions have increased enormously around the world due to economic globalization, which leads to the loss of biodiversity.[75]​ Ecosystems that are vulnerable to biological invasions include coastal areas, freshwater ecosystems, islands, and places with a Mediterranean climate. One study conducted a meta-analysis on the impacts of invasive species on Mediterranean-type ecosystems and observed a significant loss in native species richness.[77]​.

Global warming has changed typical conditions in several environments, allowing greater migration and distribution of species dependent on warm climates.[78] This phenomenon could result in increased biodiversity (introduction of new species into new environments) or reduced biodiversity (promotion of invasive species). A biological invasion is considered successful if the invasive species can adapt and survive in the new environment, as well as reproduce, disperse and compete with native communities.[77] Some invasive species are known to have high dispersal rates and have important implications on a regional scale. For example, in 2010, it was identified that the muskrat, raccoon dog, thrips and Chinese crab have affected 20 to 50 regions in Europe.[77]​.

Invasive species can become financial burdens for many countries. Due to ecological degradation caused by invasive species, this can alter the functionality and reduce the services that ecosystems provide. Additional costs are also expected to control the spread of biological invasion, mitigate additional impacts, and restore ecosystems. For example, the cost of damage caused by 79 invasive species between 1906 and 1991 in the United States has been estimated at US$120 billion.[77]​ In China, invasive species have reduced the country's gross domestic product (GDP) by 1.36% annually.[79]​ Managing biological invasion can also be costly. In Australia, expenditure to monitor, control, manage and research invasive weed species was approximately A$116.4 million per year, with costs paid by central and local government.[77]​ In some situations, invasive species may have benefits, such as economic returns. For example, invasive trees can be cut down for commercial forestry. However, in most cases, the economic benefits are much smaller than the cost caused by biological invasion.[74][77]​.

Overexploitation

Due to human dependence and demands, fossil fuels remain the dominant energy source globally; In the United States and other countries, approximately 78% of energy production comes from fossil fuels.[22]​[82]​ The extraction, processing, and burning of fossil fuels indirectly impacts biodiversity loss by contributing to climate change, while directly causing habitat destruction and pollution.[22]​ At fossil fuel extraction sites, land conversion, habitat loss and degradation, contamination, and pollution impact biodiversity beyond the terrestrial ecosystems; impacts freshwater, coastal and marine environments. Once fossil fuels have been extracted, they are transported, processed and refined, which also impacts biodiversity as infrastructure development requires the removal of habitats and more pollution is emitted into the environment.[22]​ For example, the construction of roads, well pads, pipelines, reservoir wells, evaporation ponds and power lines leads to habitat fragmentation and noise pollution.[82]​.

Fossil fuel exploitation tends to occur in areas with high species richness and abundance, generally located in coastal and terrestrial environments. One study identified 181 potential "high risk" areas for fossil fuel exploitation, which were areas that also harbored high levels of biodiversity. Of the 181 locations identified, 156 of these high-risk fields were not protected areas, indicating that more biodiversity could be lost with fossil fuel exploitation.[22] Future fossil fuel exploration is predicted to occur in areas with low species richness and rarity, such as the oceans and the Arctic.[83] However, this prediction does not apply to Western Asia, the Asia-Pacific, Africa, South America, and the Caribbean. (region)"), where fossil fuel and coal exploitation is expected to occur in areas with high species richness.[22]​ For example, the western Amazon (located in Brazil) is known to have high biodiversity. However, this region is also threatened by exploitation due to the large number of oil and natural gas deposits.[84] Generally, areas with large reserves of fossil fuels have a higher probability of being extracted (depending on the country's priorities). Tropical environments contain high levels of biodiversity, which will indirectly result in increased deforestation for agricultural purposes and financial gains (e.g., timber export).[84]​.

In the case of marine fauna extinctions, the dominant driver of their extinctions is not climate change or subsequent acidification, but fishing carried out by humans.[85]​[86]​[87]​ Therefore, the largest species are the most affected (with a 13 times greater probability of being under the threat of extinction), since fishermen obtain greater profits with them.[88]​.

As of 2020, global fish abundance has declined by 38% compared to the fish population in 1970.[89]​ The decline in global fish populations was first noted during the 1990s. Currently, many commercial fish have been overexploited; Approximately 27% of exploited fish stocks in the United States are classified as overexploited.[90]​ In Tasmania, more than 50% of major fishery species, such as the eastern gemfish, southern rock lobster, southern fin tuna, jack mackerel, and trumpeter, were noted to have declined over the past 75 years due to overfishing.[91]​.

Climate change

Climate change has negatively affected both terrestrial[101]​ and marine ecosystems,[102]​ and is expected to further affect many ecosystems, such as tundra, mangroves, coral reefs and caves. The increase in global temperature, the greater frequency of extreme weather events and the rise in sea level are some of the effects of climate change that will have the most significant impact.[103]​[104]​ Some of the possible consequences of these effects are the decline and extinction of species, the change in behavior in ecosystems, the increase in the prevalence of invasive species, the change from forests as carbon sinks to carbon sources, the acidification of the oceans, the alteration of the water cycle and the increase in natural disasters, among others.

Climate change is a long-term change in the average weather patterns that have come to define the Earth's local, regional and global climates. These changes have a wide range of observed effects that are synonymous with the term.[105] Climate change is any significant long-term change in the expected pattern, whether due to natural variability or as a result of human activity. Predicting the effects that climate change will have on plant biodiversity can be done using various models, although the most used are bioclimatic ones.[106]​.

Environmental conditions play a key role in defining the function and geographical distribution of plants, in combination with other factors, thereby modifying patterns of biodiversity.[107] Long-term changes in environmental conditions, which can be collectively called climate change, are known to have had an enormous impact on current patterns of plant diversity; further impacts are expected in the future.[108]​ Climate change is expected to remain one of the main drivers of biodiversity patterns in the future.[109]​[110]​[111]​ Human action is currently triggering the sixth major mass extinction our Earth has seen, changing the distribution and abundance of many plants.[112]​.

Furthermore, pre-species barriers for plants are also the indirect effects of climate change due to human activities. First, as mentioned above, the reduction in the number of birds and insects used to help pollinate plants[113]​[114]​ will reduce the possibility of mating between plants. Second, prolonged fire weather seasons can result in more severe burning conditions and shorter burn intervals, which can threaten the biodiversity of native vegetation.[115] Additionally, species habitat changes or migrations under changing climate conditions can cause non-native plants[116] and pests to cause damage to the diversity of native vegetation, making them less structurally functional and more vulnerable to damage. external,[117]​ which would ultimately lead to the loss of biodiversity.

Plant and animal populations are interconnected. There are a number of examples in nature that show this dependence. Consider pollinator-dependent plant species that show observable sensitivity to pollinator activity.[118]​ A 2007 study looked at the relationship between plant diversity and phenology, and experimentally determined that plant diversity influenced the flowering time of the community as a whole.[118]​ Flowering time is an important piece in the pollination puzzle, as it affects the food supply for plants. pollinators.[119]​ This, in turn, can play an important role in agricultural activities[119]​ and global food security.[120]​.

indirect causes

The effects on biodiversity can be framed in the Anthropocene, the current geological era in which the human species is the one that determines the fundamental processes of the biosphere,[125]​ thus leading to global environmental change.[126]​ Virtually all aspects of global change are caused primarily by the rapid growth of the human population and the increase in per capita resource consumption").[127]​ The latter is largely driven by the logic of the capitalist system that constantly seeks to create goods to accumulate. wealth, whether by solving existing basic and historical-social needs or creating new ones,[128]​ regardless of the environmental costs and the injustice it represents towards other animals and species.[129]​.

The main drivers of biotic stress and the resulting accelerated rate of loss are, among other threats:[130]​.

1. • Habitat loss and degradation

: Intensification of land use (and consequent land loss/habitat loss) has been identified as an important factor in the loss of ecological services due to direct effects, as well as loss of biodiversity.[131]​

: The main factors that lead to the change in land use and habitat fragmentation are livestock and agriculture, real estate developers and road builders.[132]​[23]​[133]​.

2. • Climate change through heat stress and drought stress.

3. • Excessive load of nutrients and other forms of pollution.

4. • Overexploitation and unsustainable use of natural resources (for example, unsustainable fishing methods)

: In 2006, humans used 25% more natural resources than the planet can regenerate annually, and this number has continued to rise.[134]​ At the United Kingdom's consumption rate of 2022, the human species would need 2.6 planet Earths to provide enough resources to the world's population. Human consumption now requires the natural resources of 1.75 planet Earths instead of just one, and half of this is for food alone.[135]​

: It is worth noting that the consumption of foods of animal origin (and therefore livestock and fishing) is the main cause of the extinctions of modern species,[136]​ as it is the largest driver of habitat loss, the main cause of climate change, soil loss, overfishing, sedimentation of coastal areas, facilitation of invasions of exotic species,[137]​ water pollution[138]​ and decline in large predators[139]​ and of wild herbivores.[140]​.

5. • Armed conflicts, which disrupt human livelihoods and institutions, contribute to habitat loss and intensify the overexploitation of economically valuable species, leading to population decline and local extinction.[141]​.

Loss of terrestrial species richness

Humans have altered plant richness in regional landscapes around the world, transforming more than 75% of terrestrial biomes into “anthropogenic biomes.” This is seen through the loss of native species replaced and overtaken by agriculture. Models indicate that approximately half of the biosphere has seen a "substantial net anthropogenic change" in species richness.[145]​.

In 2017, several publications described the drastic reduction in absolute insect biomass and number of species in Germany and North America over a 27-year period.[146]​[147]​ As possible reasons for the decline, the authors highlight neonicotinoids and other agrochemicals. A work published in 2017 in PLOS One concludes that "the generalized decrease in insect biomass is alarming."[148]​.

For example, critical declines in earthworms (more than 80% on average) have been recorded under non-ecological farming practices.[149] Earthworms play an important role in ecosystem function.[149] For example, they help with biological processing in soil, water and even greenhouse gas balance.[150]​ The decline in earthworm populations is said to be due to five reasons; soil degradation and habitat destruction, climate change, biological invasion by non-native species, poor soil management and pollutant loading.[150] Factors such as tillage practices "Till (agriculture)") and intensive land use decimate the soil and plant roots that earthworms use to create their biomass, causing carbon and nitrogen cycles to be negatively affected. Knowledge of the diversity of earthworm species is quite limited since not even 50% of them have been described. More studies should be conducted on earthworms and how they provide their ecosystem services to gain a better understanding of how to preserve their diversity.[150]​ Due to declining earthworm populations, the Secretariat of the Convention on Biological Diversity has taken measures that promote the restoration and maintenance of the many diverse species of earthworms.[150]​.

Certain types of pesticides, neonicotinoids, are likely contributing to the decline of certain bird species.[151] A study funded by BirdLife International confirms that 51 bird species are critically endangered and 8 could be classified as extinct or endangered. Almost 30% of extinction is due to hunting and trapping for the exotic pet trade. Deforestation, caused by unsustainable logging and agriculture, could be the next factor in extinction, as birds lose their habitat and food. The biologist Luisa Arnedo said: “as soon as the habitat runs out, they run out too.”[152]​.

Within the Amazon rainforest there is an area called Belém "Belém (Brazil)") that can be described as having a high level of endemism. However, in Belém 76% of the land has already been stripped of its natural resources, including forest trees.[153]​ Within the area, bird species are strongly affected by deforestation, having been put in that situation, 56% of the birds are now in danger of extinction. With climate change and habitat change, the bird population will continue to decline. Even with protected areas of land, the efficiency at which birds are conserved is low.[153]​.

Modern bird hunting and trapping is a common practice in South America. Some cultures in Brazil encourage hunting and capturing birds for commercial reasons. Some reasons include selling wild birds as pets, raising birds and selling offspring, selling birds for food, and selling them for religious and medicinal purposes.[154]​.

Another growing threat to bird populations is power line collisions and electrocutions.[155] Migratory species are at increased risk of collision accidents, and up to one billion birds die each year due to collisions with buildings in the United States.[156]

Loss of aquatic species richness

Freshwater ecosystems ranging from swamps, deltas and rivers make up up to 1% of the Earth's surface. Although they make up such a small proportion of the earth, freshwater ecosystems are important because these types of habitats support approximately a third of vertebrate species.[157] Freshwater species are beginning to decline at twice the rate of other species, such as those found on land or within the ocean; this rapid loss has already placed 27% of the 29,500 freshwater-dependent species on the IUCN Red List.[157] The decline such rapid decline of freshwater species is due to existing poor systems that do not provide any protection to their biodiversity.

A study by 16 global conservation organizations found that the biodiversity crisis is most acute in freshwater ecosystems, with a rate of decline twice that of oceans and forests. Global freshwater fish populations are collapsing due to anthropogenic impacts such as pollution and overfishing. Migratory fish populations have declined by 76% since 1970, and large "megafish" populations have declined by 94% with 16 species declared extinct in 2020.[158]​.

Marine biodiversity encompasses any living organism that resides in the ocean and describes several complex relationships within marine ecosystems.[90]​ On a local and regional scale, marine communities are better understood than marine ecosystems on a global scale. As of 2018, it was estimated that approximately 240,000 marine species have been documented.[89]​ According to this prediction, the discovery of total marine species ranges between 11% and 78% due to uncertainties in global marine biodiversity.[89]​ However, the number of described marine species remains low compared to terrestrial species due to several factors, including the assignment of different names for the same species and a taxonomic classification. insufficient.[90]​ It is likely that many undocumented species have already disappeared. Because not all marine species have been described, it is difficult to provide an accurate estimate of global extinction in marine ecosystems. As a result, the abundance of marine species remains uncertain, with estimates ranging from 178,000 to 10 million oceanic species.[90]​.

With anthropogenic pressure, this results in human activities having the greatest influences on marine biodiversity, with the main drivers of global extinction being habitat loss, pollution, invasive species and overexploitation.[159]​[160]​ Greater pressure is being placed on marine ecosystems with human settlements near coastal areas.[161]​ Other indirect factors that have resulted in the decline of marine species include climate change and change in oceanic biochemistry.[159]​.

Overexploitation has resulted in the extinction of more than 20 described marine species, including seabirds, marine mammals, algae, and fish. Examples of extinct marine species include the Steller's sea cow (Hydrodamalis gigas) and the Caribbean monk seal (Monachus tropicalis). However, not all extinctions are due to humans. For example, in 1930, the seagrass limpet () became extinct once the seagrass population of declined due to exposure to a disease. The were greatly affected as the Zostera marina was their only habitat.[90]​.

Ecological effects of biodiversity loss

The loss of biodiversity also threatens the structure and proper functioning of the ecosystem. Although all ecosystems are capable of adapting to the stresses associated with reduced biodiversity to some extent, biodiversity loss reduces the complexity of an ecosystem, as roles once played by multiple interacting species or multiple interacting individuals are played by fewer or none. community. At higher levels of extinction (40 to 60 percent of species), the effects of species loss were ranked with those of many other important drivers of environmental change, such as ozone pollution, acid deposition in forests, and nutrient pollution.[162]​ Finally, effects are also seen in human needs, such as clean water, air, and food production over time. For example, studies over the past two decades have shown that more biologically diverse ecosystems are more productive.[163]​ As a result, there has been growing concern that high modern extinction rates, due to habitat loss, overexploitation, and other human-caused environmental changes, could reduce nature's ability to provide goods and services such as food, clean water, and a stable climate.[164]​.

An October 2020 analysis by Swiss Re found that one-fifth of all countries are at risk of ecosystem collapse as a result of anthropogenic habitat destruction and increased wildlife loss.[165]​.

Impact on food and agriculture

In 2019, the Food and Agriculture Organization of the United Nations produced its first report on The state of the world's biodiversity for food and agriculture, which warned that "many key components of biodiversity for food and agriculture at the genetic, species and ecosystem levels are in decline."[166]​[167]​ The report states that this is being caused by "a variety of drivers operating at a variety of levels" and, more specifically, that "Major global trends, such as changes in climate, international markets and demographics, give rise to more immediate drivers, such as land use, climate change, pollution and overuse of external inputs, overexploitation and the proliferation of invasive species. Interactions between drivers often exacerbate their effects on biodiversity for food and agriculture (BFA). Demographic changes, urbanization, markets, trade and consumer preferences [the countries that contributed contributions to the report] are reported to have a strong influence on food systems, often with negative consequences for BAA and the ecosystem services it provides. However, these drivers are also reported to open up opportunities to make food systems more sustainable, for example through the development of markets for biodiversity-friendly products." agricultural and food production systems] are changes in the use and management of land and water" and that "the loss and degradation of forests and aquatic ecosystems and, in many production systems, the transition to intensive production of a reduced number of species, breeds and varieties, remain the main drivers of the loss of BFA and ecosystem services."[166]​.

The health of humans depends largely on the product of an ecosystem. With the loss of biodiversity, there is also a great impact on human health. Biodiversity makes it possible for humans to have a sustainable level of soil and the means to have the genetic factors to have food.[168]​.

Many activists and academics have suggested that there is a connection between plant patent protection and the loss of crop biodiversity,[169]​ although such claims are disputed.[170]​.

Human health

The decline in biodiversity has several implications for human health. One of those implications is the loss of medicinal plants. The use of plants for medicinal purposes is extensive, with ~70 to 80% of people worldwide relying solely on plant-based medicine as their primary source of healthcare.[171]​ This reliance on plants for medicinal purposes is especially prevalent in developing countries.[171]​ Local knowledge about medicinal plants is useful for the detection of new herbal medicines that may be useful in the treatment of diseases.[172]​ The peoples and communities that continuously residing in a single geographic area over time, they create, transmit, and apply widespread information about the area's medicinal resources.[172] Formal scientific methods have been useful in identifying active ingredients used in ethnopharmacy and applying them to modern medicines. However, it is important that medicinal resources are appropriately managed as they are traded globally to avoid endangering species.[172] Changes to local ecosystems (such as access to food and clean water) can indirectly affect the local economy and society (the livelihoods and social interaction between people living in the affected area). Therefore impacting people's health.[173]​.

According to the Biodiversity of Health Hypothesis, reducing people's contact with the natural environment and biodiversity can negatively affect the human commensal microbiota and its immunomodulatory capacity "Immunity (medicine)". interconnected.[174]​[175]​[176]​.

Urbanization and habitat fragmentation increasingly lead to the loss of connection between humans and the natural environment. Furthermore, non-communicable immunological diseases have become increasingly common in recent decades, especially in urbanized communities.[177]​.

Existen múltiples desafíos de conservación cuando se trata de la pérdida de biodiversidad que se necesita hacer un esfuerzo conjunto a través de políticas públicas, soluciones económicas, monitoreo y educación por parte de gobiernos, ONG, conservacionistas, etc.[178]​ Se requieren incentivos para proteger las especies y conservar su hábitat natural y desincentivar la pérdida y degradación del hábitat (p. ej., implementar el desarrollo sostenible, incluidas las metas del ODS 15). Otras formas de lograr este objetivo son hacer cumplir leyes que eviten la caza furtiva de la vida silvestre, protejan a las especies de la sobrecaza y la pesca excesivas y mantengan intactos y seguros los ecosistemas de los que dependen de las invasiones de especies y la conversión del uso de la tierra.[17]​ Además, los modelos basados en la conservación, como Global Safety Net, se desarrollan continuamente para considerar las conexiones ecológicas que deben abordarse para mitigar de manera efectiva la pérdida de biodiversidad.[179]​ Según la Plataforma Intergubernamental de Ciencia y Política sobre Biodiversidad y Servicios de los Ecosistemas (IPBES), la acción para proteger la biodiversidad es muy rentable porque reduce el riesgo de pandemias debido a patógenos de la vida silvestre.[180]​.

Los conservacionistas y los científicos de investigación sostenible de todo el mundo también han desarrollado enfoques basados en sistemas para ayudar a mitigar la pérdida de biodiversidad. Esta metodología permite a los científicos crear marcos contextuales que consideran los muchos matices y vínculos de la conservación ambiental como las huellas ecológicas, los límites planetarios, la economía ecológica, etc.[181]​ Tener en cuenta todas las formas en que se cruzan el mundo natural y el humano puede ayudar a los investigadores a comprender las complejidades que conducen a la pérdida de biodiversidad y encontrar patrones que se pueden aplicar a situaciones similares. Un ejemplo de este tipo de marcos es el resultado final triple, que ha sido adoptado por muchas empresas y organizaciones para evaluar su impacto y progreso hacia la unión del éxito social, ambiental y económico.

Philosophy, ethics and law

After the end of World War II, a profound, rapidly approaching environmental crisis began to become visible on the horizon. Since then, the scientific community, academies, and political elites began to devote more focused attention to the issue, which also took to the streets and the media in the first major demonstrations of the nascent environmental movement.[182]​[183]​[184][185]​ Preservation programs were established, numerous protected areas were created, green political parties emerged, popular activism grew and absorbed a considerable scientific base, protectionist legislation greatly multiplied, even integrated the topic in the basic school curriculum in many countries, and governments around the world have established several international conventions to address the challenge.[186]​[187]​[188]​[189]​.

Science has discovered that many higher animals are capable of suffering, have high intelligence and some level of self-awareness, and may have some emotional life. Countless other beings are possibly endowed with some form of sensitivity to suffering and abuse, in addition to possessing sensory capacities that are still little known and unmatched among humans.[190]​[191]​.

Some similar sensitivity, others suppose, plants may also have. Studies and even empirical evidence indicate that plants, although they lack a nervous system, have the ability to "map" their environment through receptors sensitive to chemicals, light, heat, humidity and tactile stimuli, capabilities that make them react and adapt to the environment.[192][193][194]​.

These data, which have been accumulating in recent years, have also updated an ethical question that had been debated for a long time by philosophers, religious people and legislators, which had already been expressed in 1972 in the Stockholm Declaration, adopted by the UN, and what became perfectly clear from the elaboration of the CB: "Do we have the right to destroy biodiversity?" Although for many centuries nature has been understood predominantly as a good to be exploited at the will of man, existing only to serve him, and although national sovereignty and private property are universally recognized principles, and therefore, although no legal entity possesses "biodiversity", the organisms that live under its jurisdiction generally remain, for all intents and purposes, its exclusive possession, just like inanimate objects; For many, the answer to that question is: "No".[195]​[196]​[187]​ And this denial was ratified both in the CB, which recognized the intrinsic value") of nature and its variety, and in other international conventions and commitments, such as the Rio Declaration, Agenda 21 and the Earth Charter.[195]​[187]​ The Declaration of Stockholm, for example, states that man has “a special responsibility to safeguard and wisely manage the wildlife heritage and its habitats, which are currently in grave danger,”[197]​ and the Earth Charter, drafted during the Rio 92 conference and adopted by UNESCO in 2002 as a global code of ethics, receiving the adherence of more than 4,500 governmental and international organizations, even goes so far as to explicitly say that “the protection of vitality, diversity and beauty of the Earth is a sacred duty.

Related to this are other legal issues and threats to human rights linked to biodiversity, “since they are undeniable”, in the words of Hellen de Barros Franco, “the relationships of interdependence between the right to life and the right to an ecologically balanced and sustainable environment, so that it becomes one of the decisive factors to guarantee the healthy quality of life and the dignity of the human person.” Among these issues are the right of people to environmental education as a way of building citizenship and sociocultural advancement; inequalities in the social distribution of wealth derived from nature;[199]​[200]​ the links between environmental damage and civil wars, terrorism and international conflicts;[201]​ illegal hunting, fishing or trade in live specimens and natural products, especially of vulnerable and threatened species and in protected areas; the greatest impact of the losses on the poorest, traditional communities and indigenous peoples who depend exclusively or mainly on nature; conflicts over ownership of land and its resources,[200]​[202]​[203]​ and moral conflicts and the ecological and social impacts of political corruption, commercial genetic engineering and scientific, medical, pharmaceutical and cosmetic research with animals and plants, which include vivisection and are often redundant or irrelevant or futile in their purpose.[200]​[204]​[205]​[206]​.

International action

There are many organizations dedicated to the cause of prioritizing conservation efforts, such as the International Union for Conservation of Nature and Natural Resources (IUCN) Red List of Threatened Species and the United States Endangered Species Act. British environmental scientist Norman Myers and his colleagues have identified 25 terrestrial biodiversity hotspots that could serve as priorities for habitat protection.[207]

Many governments around the world have conserved parts of their territories under the Convention on Biological Diversity (CBD), a multilateral treaty signed in 1992-1993. The 20 Aichi Biodiversity Targets, part of the CBD Strategic Plan 2011-2020, were published in 2010.

In 2019, the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), an international organization formed to play a similar role to the Intergovernmental Panel on Climate Change (IPCC),[209]​ published the Global Assessment Report on Biodiversity and Ecosystem Services. which said that up to one million plant and animal species are at risk of extinction due to activities [17]​[18]​ An October 2020 IPBES report indicated that the same human activities that are the underlying drivers of climate change and biodiversity loss, such as the destruction of wildlife and wild habitats, are also the same drivers of pandemics, including the COVID-19 pandemic.[210]​.

According to the United Nations' 2020 Global Biodiversity Outlook, of the 20 biodiversity targets set by the Aichi Biodiversity Targets in 2010, only 6 were "partially met" by the 2020 deadline. unsustainable."[212]​ The report also singled out Australia, Brazil and Cameroon, and the Galapagos Islands (Ecuador) for having lost one of their animals to extinction in the last 10 years.[213]​ After this, the leaders of 64 nations and the European Union committed to stopping environmental degradation and restoring the natural world. The leaders of some of the world's biggest polluters, namely China, India, Russia, Brazil and the United States, were not among them.[214] Some experts argue that the United States' refusal to ratify the Convention on Biological Diversity is harming global efforts to stop the extinction crisis.[215] Top scientists say that even if the 2010 targets had been met, it probably would not have resulted in any substantial reduction in extinction rates. [20]​[1]​ Others have expressed concern that the Convention on Biological Diversity does not go far enough and argue that the goal should be zero extinctions by 2050, as well as halving the impact of unsustainable food production on nature. That the objectives are not legally binding has also been the subject of criticism.[216]​.

In 2020, with the adoption of the 2020 deadline for the Aichi Biodiversity Targets, scientists proposed a measurable near-term biodiversity target, comparable to the following 2°C global warming target: keeping extinctions of described species well below 20 per year for the next 100 years in all major groups (fungi, plants, invertebrates and vertebrates) and in all ecosystem types (marine, freshwater and terrestrial).[217]​.

Perspectives

Without a doubt, humanity still has a long way to go before it manages to recycle its way of life and consolidate a large-scale sustainable development model, which makes possible the conservation of biodiversity in the name of the good of nature and also of man. The misinformation of the majority of people, their irreducible habits and prejudices, which lead to an irrational resistance to accepting the conclusions of science and widely adopting its recommendations, the disconnection between fields of knowledge and the inconsistencies of official policies, the routine underestimation of environmental services, the lack of more effective dialogue and cooperation between nations, the primacy of politics and economics over science and human values, among other factors, continue to act very effectively to nullify the power of the already accumulated, solid and superabundant scientific evidence, which prevents or delays the progress of the works.[130]​[238]​[241]​[235]​[219]​[220]​.

The same scientists who document environmental problems and warn about their seriousness clarify that the insufficiency of data and means, the uncertainty, should not be a reason for discouragement and perplexity - although caution is strongly recommended - nor do they justify procrastination, as the gaps should be understood as unavoidable and as useful beacons of knowledge and action, much can be done with the available resources and with the lessons of the experiences already carried out, including the disastrous ones, and we must start from what that we have.[130]​[225]​[242]​[243]​[130]​.

If there is so much left to do, if the risks of inaction are so high and worrying, and if the negative consequences must manifest so soon, as they are already doing with increasing severity, it is necessary to take advantage of the changes now and without hesitation.[130]​ The CBD Secretariat was emphatic in analyzing the prospects for the future:.

Along the same lines, the UN Secretary General, Ban Ki-moon, declared:

In fact, popular awareness seems to be growing,[244]​ the UN declared 2010 as the International Year of Biodiversity to draw general attention to the issue,[245]​ many actions and programs are already underway, and many more are being planned, at international, national and local levels, with promising results in several limited aspects, which need to be expanded across the board.[130]​.

However, the pace of human population growth over this century will be a critical factor in the evolution of biodiversity decline, but there is still no firm basis for predictions. Estimates vary widely, from a maximum of 16 billion people in 2100, and a return to a level of 5.5 billion, leaving open a wide variety of possible scenarios.[246]​ But preventive attitudes are still strongly indicated, and to mitigate the dramatic situation already being faced, the CB recommends, among others, the following measures:[130]​.

This article incorporates text from a free content work. Licensed under CC BY-NC-SA 3.0 IGO License statement.pdf): The State of the World’s Biodiversity for Food and Agriculture, FAO, FAO. For more information on how to reuse text from Wikipedia, see the terms of use.

• - This work contains a translation derived from «Biodiversity loss» from Wikipedia in English, specifically from this version, published by its editors under the GNU Free Documentation License and the Creative Commons Attribution-ShareAlike 4.0 International License.

• - This work contains a translation derived from «Declínio contemporâneo da biodiversitye Mundial» from Wikipedia in Portuguese, specifically from this version, published by its editors under the GNU Free Documentation License and the Creative Commons Attribution-ShareAlike 4.0 International License.

• - Global Biodiversity Outlook Convention on Biological Diversity.

• - Biodiversity: Why the nature crisis matters, in five graphics. BBC, September 30, 2020.

• - Scientists describe 'hidden biodiversity crisis' as variation within species is lost. Phys.org, March 1, 2021.

• - Biodiversity loss risks 'ecological meltdown' - scientists. BBC, October 10, 2021.

• - The Biodiversity Crisis Needs Its Net Zero Moment. Wired, December 17, 2021.

Contenido

La biodiversidad se define comúnmente como la variedad de vida en la Tierra en todas sus formas, incluida la diversidad de especies, sus variaciones genéticas y la interacción de estas formas de vida. Sin embargo, desde finales del siglo , la pérdida de biodiversidad causada por el comportamiento humano ha causado impactos más severos y duraderos.[17]​ Los principales científicos y el histórico Informe de Evaluación Global sobre Biodiversidad y Servicios de los Ecosistemas del IPBES afirman que el crecimiento de la población humana y el consumo excesivo son los factores principales de esta disminución en biodiversidad.[18]​[19]​[20]​[1]​[21]​ Los impulsores humanos de la pérdida de biodiversidad incluyen la alteración del hábitat, la contaminación y la sobreexplotación de los recursos naturales.[22]​.

Land use change

Examples of land use changes include deforestation, intensive monoculture, and urbanization.[41]​.

The 2019 IPBES Global Assessment Report on Biodiversity and Ecosystem Services states that industrial agriculture is the main driver of biodiversity collapse.[42]​[18]​ The UN's Global Biodiversity Outlook 2014 estimates that 70% of the projected loss of terrestrial biodiversity is caused by the use of agriculture. Additionally, more than a third of the planet's land surface is used for crops and livestock grazing.[43] Agriculture destroys biodiversity by converting natural habitats into intensively managed systems and by releasing pollutants, including greenhouse gases. Food value chains further amplify impacts, with this effect exacerbated through energy use, transportation, and waste.[44] The direct effects of urban growth on habitat loss have been well characterized: the construction of infrastructure often results in habitat destruction and fragmentation. Increased urbanization greatly reduces biodiversity when large areas of natural habitat are fragmented,[45]​ leading to altered species selection processes, causing many to adapt to urban environments or move away from these urbanized areas.[46]​ As large patches of disturbed soil grow, small patches of habitat cannot support the same level of genetic or taxonomic diversity as before, while some of the most sensitive species may become extinct. locally.[47]​ Species with abundant populations are reduced due to small fragmented areas, which causes an increase in the isolation of species and forces them to go to edge habitats and adapt to foraging elsewhere.[45]​ Human-caused habitat fragmentation tends to create barriers that hinder dispersal, preventing species from moving with their ideal niche as it shifts due to disturbances such as climate change.[48]​ Although The negative effects of fragmentation tend to be well known, the risk of fragmentation tends to have minor effects on biodiversity and can even change and strengthen certain relationships between species.[49]​.

According to a 2020 study published in Nature Sustainability, more than 17,000 species are at risk of losing their habitat by 2050 as agriculture continues to expand to meet future food needs. Researchers suggest that greater agricultural efficiency in developing countries as well as a large-scale population shift to plant-based diets could help reduce habitat loss.[50] Similarly, a Chatham report House also postulated that a global shift toward primarily plant-based diets would free up enough land to allow for the restoration of ecosystems and biodiversity, because in the 2010s more than 80% of all agricultural land in the world was used to raise animals.[51] A 2022 study published in Science concluded that at least 64 million square kilometers, 44% of the Earth's surface, require conservation attention (from protected areas to land use policies). soil) to ensure important zones of biodiversity, ecologically intact areas and optimal locations for the representation of species ranges and ecoregions.[52]​.

Pollution

Four commonly studied and monitored greenhouse gases are water vapor, carbon dioxide, methane, and nitrous oxide (nitrogen(I) oxide). Over the past 250 years, concentrations of carbon dioxide and methane have increased, along with the introduction of purely anthropogenic emissions such as hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride into the atmosphere.[53] These pollutants are emitted into the atmosphere by the burning of fossil fuels and biomass ("Biomass (energy)"), deforestation, and agricultural practices that amplify the effects of climate change.[54][55]​ As higher concentrations of greenhouse gases are released into the atmosphere, the Earth's surface temperature increases. This is because greenhouse gases are able to absorb, emit and trap heat from the Sun that enters the Earth's atmosphere.[53]​ With the increase in temperature expected from the increase in greenhouse gases, higher levels of air pollution, greater variability in weather patterns, intensification of the effects of climate change and changes in the distribution of vegetation in the landscape are predicted.[22][56]​.

Other pollutants released from industrial and agricultural activity include sulfur dioxide and nitrogen oxides.[53] Once sulfur dioxide and nitrogen oxide are introduced into the atmosphere, they can react with cloud droplets (cloud condensation nuclei), raindrops, or snowflakes, forming sulfuric acid and nitric acid. With the interaction between water droplets and sulfuric and nitric acids, "wet deposition" occurs and creates acid rain.[57]​[58]​ As a result, these acids would be displaced to various environments and vegetation during precipitation, having a significant aerial distance (hundreds of kilometers) from the emission source. Sulfur dioxide and nitrogen oxide can also be displaced over vegetation through dry deposition").[59]​.

The concentration of sulfur dioxide and nitrous oxide has many implications in aquatic ecosystems, including changing acidity, increasing nitrogen and aluminum content, and altering biogeochemical processes.[59] Generally, sulfur dioxide and nitrous oxide have no direct physiological effects after an organism is exposed to them; Most of the effects develop through accumulation and prolonged exposure of these gases in the environment, modifying the chemistry of soil and water.[59]​[60]​ Consequently, sulfur contributes greatly to the acidification of lakes and oceans, and nitrogen initiates the eutrophication of continental and coastal water bodies that lack nitrogen. Both phenomena alter the composition of the native aquatic biota and influence the original food web with a higher level of acidity, minimizing aquatic and marine biodiversity.[58][59]​.

Nitrogen deposition has also affected terrestrial ecosystems, including forests, grasslands, alpine regions and bogs.[59]​ Nitrogen input has altered the natural biogeochemical cycle and promoted soil acidification.[61]​ As a result, plant and animal species composition and ecosystem functionality are likely to decline due to increased soil sensitivity: contributing to slower forest growth, damage to trees at higher elevations. higher and leads to the replacement of native biota with nitrogen-loving species.[17]​[59]​ In addition, sulfate and nitrate can leach from the soil, removing essential nutrients such as calcium and magnesium, and deposit in freshwater, coastal and oceanic environments, promoting eutrophication.[59]​.

Invasive species

Invasive species have important implications for biodiversity loss as they have degraded various ecosystems around the world. Invasive species are migratory species that have outcompeted and displaced native species, altered species richness and food webs, and changed ecosystem functions and services.[74]​[75]​ Invasive species are introduced into a new habitat, whether intentionally or unintentionally, by human activities. The most common methods for introducing aquatic invasive species are by ballast water, on ship hulls, and attached to equipment such as fishing nets.[76]​ According to the Millennium Ecosystem Assessment, invasive species are considered one of the top five drivers of biodiversity loss.[77]​ Over the past half century, biological invasions have increased enormously around the world due to economic globalization, which leads to the loss of biodiversity.[75]​ Ecosystems that are vulnerable to biological invasions include coastal areas, freshwater ecosystems, islands, and places with a Mediterranean climate. One study conducted a meta-analysis on the impacts of invasive species on Mediterranean-type ecosystems and observed a significant loss in native species richness.[77]​.

Global warming has changed typical conditions in several environments, allowing greater migration and distribution of species dependent on warm climates.[78] This phenomenon could result in increased biodiversity (introduction of new species into new environments) or reduced biodiversity (promotion of invasive species). A biological invasion is considered successful if the invasive species can adapt and survive in the new environment, as well as reproduce, disperse and compete with native communities.[77] Some invasive species are known to have high dispersal rates and have important implications on a regional scale. For example, in 2010, it was identified that the muskrat, raccoon dog, thrips and Chinese crab have affected 20 to 50 regions in Europe.[77]​.

Invasive species can become financial burdens for many countries. Due to ecological degradation caused by invasive species, this can alter the functionality and reduce the services that ecosystems provide. Additional costs are also expected to control the spread of biological invasion, mitigate additional impacts, and restore ecosystems. For example, the cost of damage caused by 79 invasive species between 1906 and 1991 in the United States has been estimated at US$120 billion.[77]​ In China, invasive species have reduced the country's gross domestic product (GDP) by 1.36% annually.[79]​ Managing biological invasion can also be costly. In Australia, expenditure to monitor, control, manage and research invasive weed species was approximately A$116.4 million per year, with costs paid by central and local government.[77]​ In some situations, invasive species may have benefits, such as economic returns. For example, invasive trees can be cut down for commercial forestry. However, in most cases, the economic benefits are much smaller than the cost caused by biological invasion.[74][77]​.

Overexploitation

Due to human dependence and demands, fossil fuels remain the dominant energy source globally; In the United States and other countries, approximately 78% of energy production comes from fossil fuels.[22]​[82]​ The extraction, processing, and burning of fossil fuels indirectly impacts biodiversity loss by contributing to climate change, while directly causing habitat destruction and pollution.[22]​ At fossil fuel extraction sites, land conversion, habitat loss and degradation, contamination, and pollution impact biodiversity beyond the terrestrial ecosystems; impacts freshwater, coastal and marine environments. Once fossil fuels have been extracted, they are transported, processed and refined, which also impacts biodiversity as infrastructure development requires the removal of habitats and more pollution is emitted into the environment.[22]​ For example, the construction of roads, well pads, pipelines, reservoir wells, evaporation ponds and power lines leads to habitat fragmentation and noise pollution.[82]​.

Fossil fuel exploitation tends to occur in areas with high species richness and abundance, generally located in coastal and terrestrial environments. One study identified 181 potential "high risk" areas for fossil fuel exploitation, which were areas that also harbored high levels of biodiversity. Of the 181 locations identified, 156 of these high-risk fields were not protected areas, indicating that more biodiversity could be lost with fossil fuel exploitation.[22] Future fossil fuel exploration is predicted to occur in areas with low species richness and rarity, such as the oceans and the Arctic.[83] However, this prediction does not apply to Western Asia, the Asia-Pacific, Africa, South America, and the Caribbean. (region)"), where fossil fuel and coal exploitation is expected to occur in areas with high species richness.[22]​ For example, the western Amazon (located in Brazil) is known to have high biodiversity. However, this region is also threatened by exploitation due to the large number of oil and natural gas deposits.[84] Generally, areas with large reserves of fossil fuels have a higher probability of being extracted (depending on the country's priorities). Tropical environments contain high levels of biodiversity, which will indirectly result in increased deforestation for agricultural purposes and financial gains (e.g., timber export).[84]​.

In the case of marine fauna extinctions, the dominant driver of their extinctions is not climate change or subsequent acidification, but fishing carried out by humans.[85]​[86]​[87]​ Therefore, the largest species are the most affected (with a 13 times greater probability of being under the threat of extinction), since fishermen obtain greater profits with them.[88]​.

As of 2020, global fish abundance has declined by 38% compared to the fish population in 1970.[89]​ The decline in global fish populations was first noted during the 1990s. Currently, many commercial fish have been overexploited; Approximately 27% of exploited fish stocks in the United States are classified as overexploited.[90]​ In Tasmania, more than 50% of major fishery species, such as the eastern gemfish, southern rock lobster, southern fin tuna, jack mackerel, and trumpeter, were noted to have declined over the past 75 years due to overfishing.[91]​.

Climate change

Climate change has negatively affected both terrestrial[101]​ and marine ecosystems,[102]​ and is expected to further affect many ecosystems, such as tundra, mangroves, coral reefs and caves. The increase in global temperature, the greater frequency of extreme weather events and the rise in sea level are some of the effects of climate change that will have the most significant impact.[103]​[104]​ Some of the possible consequences of these effects are the decline and extinction of species, the change in behavior in ecosystems, the increase in the prevalence of invasive species, the change from forests as carbon sinks to carbon sources, the acidification of the oceans, the alteration of the water cycle and the increase in natural disasters, among others.

Climate change is a long-term change in the average weather patterns that have come to define the Earth's local, regional and global climates. These changes have a wide range of observed effects that are synonymous with the term.[105] Climate change is any significant long-term change in the expected pattern, whether due to natural variability or as a result of human activity. Predicting the effects that climate change will have on plant biodiversity can be done using various models, although the most used are bioclimatic ones.[106]​.

Environmental conditions play a key role in defining the function and geographical distribution of plants, in combination with other factors, thereby modifying patterns of biodiversity.[107] Long-term changes in environmental conditions, which can be collectively called climate change, are known to have had an enormous impact on current patterns of plant diversity; further impacts are expected in the future.[108]​ Climate change is expected to remain one of the main drivers of biodiversity patterns in the future.[109]​[110]​[111]​ Human action is currently triggering the sixth major mass extinction our Earth has seen, changing the distribution and abundance of many plants.[112]​.

Furthermore, pre-species barriers for plants are also the indirect effects of climate change due to human activities. First, as mentioned above, the reduction in the number of birds and insects used to help pollinate plants[113]​[114]​ will reduce the possibility of mating between plants. Second, prolonged fire weather seasons can result in more severe burning conditions and shorter burn intervals, which can threaten the biodiversity of native vegetation.[115] Additionally, species habitat changes or migrations under changing climate conditions can cause non-native plants[116] and pests to cause damage to the diversity of native vegetation, making them less structurally functional and more vulnerable to damage. external,[117]​ which would ultimately lead to the loss of biodiversity.

Plant and animal populations are interconnected. There are a number of examples in nature that show this dependence. Consider pollinator-dependent plant species that show observable sensitivity to pollinator activity.[118]​ A 2007 study looked at the relationship between plant diversity and phenology, and experimentally determined that plant diversity influenced the flowering time of the community as a whole.[118]​ Flowering time is an important piece in the pollination puzzle, as it affects the food supply for plants. pollinators.[119]​ This, in turn, can play an important role in agricultural activities[119]​ and global food security.[120]​.

indirect causes

The effects on biodiversity can be framed in the Anthropocene, the current geological era in which the human species is the one that determines the fundamental processes of the biosphere,[125]​ thus leading to global environmental change.[126]​ Virtually all aspects of global change are caused primarily by the rapid growth of the human population and the increase in per capita resource consumption").[127]​ The latter is largely driven by the logic of the capitalist system that constantly seeks to create goods to accumulate. wealth, whether by solving existing basic and historical-social needs or creating new ones,[128]​ regardless of the environmental costs and the injustice it represents towards other animals and species.[129]​.

The main drivers of biotic stress and the resulting accelerated rate of loss are, among other threats:[130]​.

1. • Habitat loss and degradation

: Intensification of land use (and consequent land loss/habitat loss) has been identified as an important factor in the loss of ecological services due to direct effects, as well as loss of biodiversity.[131]​

: The main factors that lead to the change in land use and habitat fragmentation are livestock and agriculture, real estate developers and road builders.[132]​[23]​[133]​.

2. • Climate change through heat stress and drought stress.

3. • Excessive load of nutrients and other forms of pollution.

4. • Overexploitation and unsustainable use of natural resources (for example, unsustainable fishing methods)

: In 2006, humans used 25% more natural resources than the planet can regenerate annually, and this number has continued to rise.[134]​ At the United Kingdom's consumption rate of 2022, the human species would need 2.6 planet Earths to provide enough resources to the world's population. Human consumption now requires the natural resources of 1.75 planet Earths instead of just one, and half of this is for food alone.[135]​

: It is worth noting that the consumption of foods of animal origin (and therefore livestock and fishing) is the main cause of the extinctions of modern species,[136]​ as it is the largest driver of habitat loss, the main cause of climate change, soil loss, overfishing, sedimentation of coastal areas, facilitation of invasions of exotic species,[137]​ water pollution[138]​ and decline in large predators[139]​ and of wild herbivores.[140]​.

5. • Armed conflicts, which disrupt human livelihoods and institutions, contribute to habitat loss and intensify the overexploitation of economically valuable species, leading to population decline and local extinction.[141]​.

Loss of terrestrial species richness

Humans have altered plant richness in regional landscapes around the world, transforming more than 75% of terrestrial biomes into “anthropogenic biomes.” This is seen through the loss of native species replaced and overtaken by agriculture. Models indicate that approximately half of the biosphere has seen a "substantial net anthropogenic change" in species richness.[145]​.

In 2017, several publications described the drastic reduction in absolute insect biomass and number of species in Germany and North America over a 27-year period.[146]​[147]​ As possible reasons for the decline, the authors highlight neonicotinoids and other agrochemicals. A work published in 2017 in PLOS One concludes that "the generalized decrease in insect biomass is alarming."[148]​.

For example, critical declines in earthworms (more than 80% on average) have been recorded under non-ecological farming practices.[149] Earthworms play an important role in ecosystem function.[149] For example, they help with biological processing in soil, water and even greenhouse gas balance.[150]​ The decline in earthworm populations is said to be due to five reasons; soil degradation and habitat destruction, climate change, biological invasion by non-native species, poor soil management and pollutant loading.[150] Factors such as tillage practices "Till (agriculture)") and intensive land use decimate the soil and plant roots that earthworms use to create their biomass, causing carbon and nitrogen cycles to be negatively affected. Knowledge of the diversity of earthworm species is quite limited since not even 50% of them have been described. More studies should be conducted on earthworms and how they provide their ecosystem services to gain a better understanding of how to preserve their diversity.[150]​ Due to declining earthworm populations, the Secretariat of the Convention on Biological Diversity has taken measures that promote the restoration and maintenance of the many diverse species of earthworms.[150]​.

Certain types of pesticides, neonicotinoids, are likely contributing to the decline of certain bird species.[151] A study funded by BirdLife International confirms that 51 bird species are critically endangered and 8 could be classified as extinct or endangered. Almost 30% of extinction is due to hunting and trapping for the exotic pet trade. Deforestation, caused by unsustainable logging and agriculture, could be the next factor in extinction, as birds lose their habitat and food. The biologist Luisa Arnedo said: “as soon as the habitat runs out, they run out too.”[152]​.

Within the Amazon rainforest there is an area called Belém "Belém (Brazil)") that can be described as having a high level of endemism. However, in Belém 76% of the land has already been stripped of its natural resources, including forest trees.[153]​ Within the area, bird species are strongly affected by deforestation, having been put in that situation, 56% of the birds are now in danger of extinction. With climate change and habitat change, the bird population will continue to decline. Even with protected areas of land, the efficiency at which birds are conserved is low.[153]​.

Modern bird hunting and trapping is a common practice in South America. Some cultures in Brazil encourage hunting and capturing birds for commercial reasons. Some reasons include selling wild birds as pets, raising birds and selling offspring, selling birds for food, and selling them for religious and medicinal purposes.[154]​.

Another growing threat to bird populations is power line collisions and electrocutions.[155] Migratory species are at increased risk of collision accidents, and up to one billion birds die each year due to collisions with buildings in the United States.[156]

Loss of aquatic species richness

Freshwater ecosystems ranging from swamps, deltas and rivers make up up to 1% of the Earth's surface. Although they make up such a small proportion of the earth, freshwater ecosystems are important because these types of habitats support approximately a third of vertebrate species.[157] Freshwater species are beginning to decline at twice the rate of other species, such as those found on land or within the ocean; this rapid loss has already placed 27% of the 29,500 freshwater-dependent species on the IUCN Red List.[157] The decline such rapid decline of freshwater species is due to existing poor systems that do not provide any protection to their biodiversity.

A study by 16 global conservation organizations found that the biodiversity crisis is most acute in freshwater ecosystems, with a rate of decline twice that of oceans and forests. Global freshwater fish populations are collapsing due to anthropogenic impacts such as pollution and overfishing. Migratory fish populations have declined by 76% since 1970, and large "megafish" populations have declined by 94% with 16 species declared extinct in 2020.[158]​.

Marine biodiversity encompasses any living organism that resides in the ocean and describes several complex relationships within marine ecosystems.[90]​ On a local and regional scale, marine communities are better understood than marine ecosystems on a global scale. As of 2018, it was estimated that approximately 240,000 marine species have been documented.[89]​ According to this prediction, the discovery of total marine species ranges between 11% and 78% due to uncertainties in global marine biodiversity.[89]​ However, the number of described marine species remains low compared to terrestrial species due to several factors, including the assignment of different names for the same species and a taxonomic classification. insufficient.[90]​ It is likely that many undocumented species have already disappeared. Because not all marine species have been described, it is difficult to provide an accurate estimate of global extinction in marine ecosystems. As a result, the abundance of marine species remains uncertain, with estimates ranging from 178,000 to 10 million oceanic species.[90]​.

With anthropogenic pressure, this results in human activities having the greatest influences on marine biodiversity, with the main drivers of global extinction being habitat loss, pollution, invasive species and overexploitation.[159]​[160]​ Greater pressure is being placed on marine ecosystems with human settlements near coastal areas.[161]​ Other indirect factors that have resulted in the decline of marine species include climate change and change in oceanic biochemistry.[159]​.

Overexploitation has resulted in the extinction of more than 20 described marine species, including seabirds, marine mammals, algae, and fish. Examples of extinct marine species include the Steller's sea cow (Hydrodamalis gigas) and the Caribbean monk seal (Monachus tropicalis). However, not all extinctions are due to humans. For example, in 1930, the seagrass limpet () became extinct once the seagrass population of declined due to exposure to a disease. The were greatly affected as the Zostera marina was their only habitat.[90]​.

Ecological effects of biodiversity loss

The loss of biodiversity also threatens the structure and proper functioning of the ecosystem. Although all ecosystems are capable of adapting to the stresses associated with reduced biodiversity to some extent, biodiversity loss reduces the complexity of an ecosystem, as roles once played by multiple interacting species or multiple interacting individuals are played by fewer or none. community. At higher levels of extinction (40 to 60 percent of species), the effects of species loss were ranked with those of many other important drivers of environmental change, such as ozone pollution, acid deposition in forests, and nutrient pollution.[162]​ Finally, effects are also seen in human needs, such as clean water, air, and food production over time. For example, studies over the past two decades have shown that more biologically diverse ecosystems are more productive.[163]​ As a result, there has been growing concern that high modern extinction rates, due to habitat loss, overexploitation, and other human-caused environmental changes, could reduce nature's ability to provide goods and services such as food, clean water, and a stable climate.[164]​.

An October 2020 analysis by Swiss Re found that one-fifth of all countries are at risk of ecosystem collapse as a result of anthropogenic habitat destruction and increased wildlife loss.[165]​.

Impact on food and agriculture

In 2019, the Food and Agriculture Organization of the United Nations produced its first report on The state of the world's biodiversity for food and agriculture, which warned that "many key components of biodiversity for food and agriculture at the genetic, species and ecosystem levels are in decline."[166]​[167]​ The report states that this is being caused by "a variety of drivers operating at a variety of levels" and, more specifically, that "Major global trends, such as changes in climate, international markets and demographics, give rise to more immediate drivers, such as land use, climate change, pollution and overuse of external inputs, overexploitation and the proliferation of invasive species. Interactions between drivers often exacerbate their effects on biodiversity for food and agriculture (BFA). Demographic changes, urbanization, markets, trade and consumer preferences [the countries that contributed contributions to the report] are reported to have a strong influence on food systems, often with negative consequences for BAA and the ecosystem services it provides. However, these drivers are also reported to open up opportunities to make food systems more sustainable, for example through the development of markets for biodiversity-friendly products." agricultural and food production systems] are changes in the use and management of land and water" and that "the loss and degradation of forests and aquatic ecosystems and, in many production systems, the transition to intensive production of a reduced number of species, breeds and varieties, remain the main drivers of the loss of BFA and ecosystem services."[166]​.

The health of humans depends largely on the product of an ecosystem. With the loss of biodiversity, there is also a great impact on human health. Biodiversity makes it possible for humans to have a sustainable level of soil and the means to have the genetic factors to have food.[168]​.

Many activists and academics have suggested that there is a connection between plant patent protection and the loss of crop biodiversity,[169]​ although such claims are disputed.[170]​.

Human health

The decline in biodiversity has several implications for human health. One of those implications is the loss of medicinal plants. The use of plants for medicinal purposes is extensive, with ~70 to 80% of people worldwide relying solely on plant-based medicine as their primary source of healthcare.[171]​ This reliance on plants for medicinal purposes is especially prevalent in developing countries.[171]​ Local knowledge about medicinal plants is useful for the detection of new herbal medicines that may be useful in the treatment of diseases.[172]​ The peoples and communities that continuously residing in a single geographic area over time, they create, transmit, and apply widespread information about the area's medicinal resources.[172] Formal scientific methods have been useful in identifying active ingredients used in ethnopharmacy and applying them to modern medicines. However, it is important that medicinal resources are appropriately managed as they are traded globally to avoid endangering species.[172] Changes to local ecosystems (such as access to food and clean water) can indirectly affect the local economy and society (the livelihoods and social interaction between people living in the affected area). Therefore impacting people's health.[173]​.

According to the Biodiversity of Health Hypothesis, reducing people's contact with the natural environment and biodiversity can negatively affect the human commensal microbiota and its immunomodulatory capacity "Immunity (medicine)". interconnected.[174]​[175]​[176]​.

Urbanization and habitat fragmentation increasingly lead to the loss of connection between humans and the natural environment. Furthermore, non-communicable immunological diseases have become increasingly common in recent decades, especially in urbanized communities.[177]​.

Existen múltiples desafíos de conservación cuando se trata de la pérdida de biodiversidad que se necesita hacer un esfuerzo conjunto a través de políticas públicas, soluciones económicas, monitoreo y educación por parte de gobiernos, ONG, conservacionistas, etc.[178]​ Se requieren incentivos para proteger las especies y conservar su hábitat natural y desincentivar la pérdida y degradación del hábitat (p. ej., implementar el desarrollo sostenible, incluidas las metas del ODS 15). Otras formas de lograr este objetivo son hacer cumplir leyes que eviten la caza furtiva de la vida silvestre, protejan a las especies de la sobrecaza y la pesca excesivas y mantengan intactos y seguros los ecosistemas de los que dependen de las invasiones de especies y la conversión del uso de la tierra.[17]​ Además, los modelos basados en la conservación, como Global Safety Net, se desarrollan continuamente para considerar las conexiones ecológicas que deben abordarse para mitigar de manera efectiva la pérdida de biodiversidad.[179]​ Según la Plataforma Intergubernamental de Ciencia y Política sobre Biodiversidad y Servicios de los Ecosistemas (IPBES), la acción para proteger la biodiversidad es muy rentable porque reduce el riesgo de pandemias debido a patógenos de la vida silvestre.[180]​.

Los conservacionistas y los científicos de investigación sostenible de todo el mundo también han desarrollado enfoques basados en sistemas para ayudar a mitigar la pérdida de biodiversidad. Esta metodología permite a los científicos crear marcos contextuales que consideran los muchos matices y vínculos de la conservación ambiental como las huellas ecológicas, los límites planetarios, la economía ecológica, etc.[181]​ Tener en cuenta todas las formas en que se cruzan el mundo natural y el humano puede ayudar a los investigadores a comprender las complejidades que conducen a la pérdida de biodiversidad y encontrar patrones que se pueden aplicar a situaciones similares. Un ejemplo de este tipo de marcos es el resultado final triple, que ha sido adoptado por muchas empresas y organizaciones para evaluar su impacto y progreso hacia la unión del éxito social, ambiental y económico.

Philosophy, ethics and law

After the end of World War II, a profound, rapidly approaching environmental crisis began to become visible on the horizon. Since then, the scientific community, academies, and political elites began to devote more focused attention to the issue, which also took to the streets and the media in the first major demonstrations of the nascent environmental movement.[182]​[183]​[184][185]​ Preservation programs were established, numerous protected areas were created, green political parties emerged, popular activism grew and absorbed a considerable scientific base, protectionist legislation greatly multiplied, even integrated the topic in the basic school curriculum in many countries, and governments around the world have established several international conventions to address the challenge.[186]​[187]​[188]​[189]​.

Science has discovered that many higher animals are capable of suffering, have high intelligence and some level of self-awareness, and may have some emotional life. Countless other beings are possibly endowed with some form of sensitivity to suffering and abuse, in addition to possessing sensory capacities that are still little known and unmatched among humans.[190]​[191]​.

Some similar sensitivity, others suppose, plants may also have. Studies and even empirical evidence indicate that plants, although they lack a nervous system, have the ability to "map" their environment through receptors sensitive to chemicals, light, heat, humidity and tactile stimuli, capabilities that make them react and adapt to the environment.[192][193][194]​.

These data, which have been accumulating in recent years, have also updated an ethical question that had been debated for a long time by philosophers, religious people and legislators, which had already been expressed in 1972 in the Stockholm Declaration, adopted by the UN, and what became perfectly clear from the elaboration of the CB: "Do we have the right to destroy biodiversity?" Although for many centuries nature has been understood predominantly as a good to be exploited at the will of man, existing only to serve him, and although national sovereignty and private property are universally recognized principles, and therefore, although no legal entity possesses "biodiversity", the organisms that live under its jurisdiction generally remain, for all intents and purposes, its exclusive possession, just like inanimate objects; For many, the answer to that question is: "No".[195]​[196]​[187]​ And this denial was ratified both in the CB, which recognized the intrinsic value") of nature and its variety, and in other international conventions and commitments, such as the Rio Declaration, Agenda 21 and the Earth Charter.[195]​[187]​ The Declaration of Stockholm, for example, states that man has “a special responsibility to safeguard and wisely manage the wildlife heritage and its habitats, which are currently in grave danger,”[197]​ and the Earth Charter, drafted during the Rio 92 conference and adopted by UNESCO in 2002 as a global code of ethics, receiving the adherence of more than 4,500 governmental and international organizations, even goes so far as to explicitly say that “the protection of vitality, diversity and beauty of the Earth is a sacred duty.

Related to this are other legal issues and threats to human rights linked to biodiversity, “since they are undeniable”, in the words of Hellen de Barros Franco, “the relationships of interdependence between the right to life and the right to an ecologically balanced and sustainable environment, so that it becomes one of the decisive factors to guarantee the healthy quality of life and the dignity of the human person.” Among these issues are the right of people to environmental education as a way of building citizenship and sociocultural advancement; inequalities in the social distribution of wealth derived from nature;[199]​[200]​ the links between environmental damage and civil wars, terrorism and international conflicts;[201]​ illegal hunting, fishing or trade in live specimens and natural products, especially of vulnerable and threatened species and in protected areas; the greatest impact of the losses on the poorest, traditional communities and indigenous peoples who depend exclusively or mainly on nature; conflicts over ownership of land and its resources,[200]​[202]​[203]​ and moral conflicts and the ecological and social impacts of political corruption, commercial genetic engineering and scientific, medical, pharmaceutical and cosmetic research with animals and plants, which include vivisection and are often redundant or irrelevant or futile in their purpose.[200]​[204]​[205]​[206]​.

International action

There are many organizations dedicated to the cause of prioritizing conservation efforts, such as the International Union for Conservation of Nature and Natural Resources (IUCN) Red List of Threatened Species and the United States Endangered Species Act. British environmental scientist Norman Myers and his colleagues have identified 25 terrestrial biodiversity hotspots that could serve as priorities for habitat protection.[207]

Many governments around the world have conserved parts of their territories under the Convention on Biological Diversity (CBD), a multilateral treaty signed in 1992-1993. The 20 Aichi Biodiversity Targets, part of the CBD Strategic Plan 2011-2020, were published in 2010.

In 2019, the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), an international organization formed to play a similar role to the Intergovernmental Panel on Climate Change (IPCC),[209]​ published the Global Assessment Report on Biodiversity and Ecosystem Services. which said that up to one million plant and animal species are at risk of extinction due to activities [17]​[18]​ An October 2020 IPBES report indicated that the same human activities that are the underlying drivers of climate change and biodiversity loss, such as the destruction of wildlife and wild habitats, are also the same drivers of pandemics, including the COVID-19 pandemic.[210]​.

According to the United Nations' 2020 Global Biodiversity Outlook, of the 20 biodiversity targets set by the Aichi Biodiversity Targets in 2010, only 6 were "partially met" by the 2020 deadline. unsustainable."[212]​ The report also singled out Australia, Brazil and Cameroon, and the Galapagos Islands (Ecuador) for having lost one of their animals to extinction in the last 10 years.[213]​ After this, the leaders of 64 nations and the European Union committed to stopping environmental degradation and restoring the natural world. The leaders of some of the world's biggest polluters, namely China, India, Russia, Brazil and the United States, were not among them.[214] Some experts argue that the United States' refusal to ratify the Convention on Biological Diversity is harming global efforts to stop the extinction crisis.[215] Top scientists say that even if the 2010 targets had been met, it probably would not have resulted in any substantial reduction in extinction rates. [20]​[1]​ Others have expressed concern that the Convention on Biological Diversity does not go far enough and argue that the goal should be zero extinctions by 2050, as well as halving the impact of unsustainable food production on nature. That the objectives are not legally binding has also been the subject of criticism.[216]​.

In 2020, with the adoption of the 2020 deadline for the Aichi Biodiversity Targets, scientists proposed a measurable near-term biodiversity target, comparable to the following 2°C global warming target: keeping extinctions of described species well below 20 per year for the next 100 years in all major groups (fungi, plants, invertebrates and vertebrates) and in all ecosystem types (marine, freshwater and terrestrial).[217]​.

Perspectives

Without a doubt, humanity still has a long way to go before it manages to recycle its way of life and consolidate a large-scale sustainable development model, which makes possible the conservation of biodiversity in the name of the good of nature and also of man. The misinformation of the majority of people, their irreducible habits and prejudices, which lead to an irrational resistance to accepting the conclusions of science and widely adopting its recommendations, the disconnection between fields of knowledge and the inconsistencies of official policies, the routine underestimation of environmental services, the lack of more effective dialogue and cooperation between nations, the primacy of politics and economics over science and human values, among other factors, continue to act very effectively to nullify the power of the already accumulated, solid and superabundant scientific evidence, which prevents or delays the progress of the works.[130]​[238]​[241]​[235]​[219]​[220]​.

The same scientists who document environmental problems and warn about their seriousness clarify that the insufficiency of data and means, the uncertainty, should not be a reason for discouragement and perplexity - although caution is strongly recommended - nor do they justify procrastination, as the gaps should be understood as unavoidable and as useful beacons of knowledge and action, much can be done with the available resources and with the lessons of the experiences already carried out, including the disastrous ones, and we must start from what that we have.[130]​[225]​[242]​[243]​[130]​.

If there is so much left to do, if the risks of inaction are so high and worrying, and if the negative consequences must manifest so soon, as they are already doing with increasing severity, it is necessary to take advantage of the changes now and without hesitation.[130]​ The CBD Secretariat was emphatic in analyzing the prospects for the future:.

Along the same lines, the UN Secretary General, Ban Ki-moon, declared:

In fact, popular awareness seems to be growing,[244]​ the UN declared 2010 as the International Year of Biodiversity to draw general attention to the issue,[245]​ many actions and programs are already underway, and many more are being planned, at international, national and local levels, with promising results in several limited aspects, which need to be expanded across the board.[130]​.

However, the pace of human population growth over this century will be a critical factor in the evolution of biodiversity decline, but there is still no firm basis for predictions. Estimates vary widely, from a maximum of 16 billion people in 2100, and a return to a level of 5.5 billion, leaving open a wide variety of possible scenarios.[246]​ But preventive attitudes are still strongly indicated, and to mitigate the dramatic situation already being faced, the CB recommends, among others, the following measures:[130]​.

This article incorporates text from a free content work. Licensed under CC BY-NC-SA 3.0 IGO License statement.pdf): The State of the World’s Biodiversity for Food and Agriculture, FAO, FAO. For more information on how to reuse text from Wikipedia, see the terms of use.

• - This work contains a translation derived from «Biodiversity loss» from Wikipedia in English, specifically from this version, published by its editors under the GNU Free Documentation License and the Creative Commons Attribution-ShareAlike 4.0 International License.

• - This work contains a translation derived from «Declínio contemporâneo da biodiversitye Mundial» from Wikipedia in Portuguese, specifically from this version, published by its editors under the GNU Free Documentation License and the Creative Commons Attribution-ShareAlike 4.0 International License.

• - Global Biodiversity Outlook Convention on Biological Diversity.

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• - The Biodiversity Crisis Needs Its Net Zero Moment. Wired, December 17, 2021.