You know, when we first set up WWF, our objective was to save endangered species from extinction. But we have failed completely; we haven’t managed to save a single one. If only we had put all that money into condoms, we might have done some good.
As with all diversity measures, it is essential to accurately classify the spatial and temporal scope of the observation. "Definitions tend to become less precise as the complexity of the subject increases and the associated spatial and temporal scales widen." Biodiversity itself is not a single concept but can be split up into various scales (e.g. ecosystem diversity vs. habitat diversity or even biodiversity vs. habitat diversity) or different subcategories (e.g. phylogenetic diversity, species diversity, genetic diversity, nucleotide diversity). The question of net loss in confined regions is often a matter of debate but longer observation times are generally thought to be beneficial to loss estimates.
In 2017, various publications describe the dramatic reduction in absolute insect biomass and number of species in Germany and North America over a period of 27 years. As possible reasons for the decline, the authors highlight neonicotinoids and other agrochemicals. Writing in the journal PLOS One, Hallman et al. (2017) conclude that "the widespread insect biomass decline is alarming."
Global state and trends figures of key elements of biodiversity important to food and agriculture
In 2019, the UN's Food and Agriculture Organization 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 genetic, species and ecosystem levels are in decline." The report states that this is being caused by “a variety of drivers operating at a range of levels” and more specifically that “major global trends such as changes in climate, international markets and demography give rise to more immediate drivers such as land-use change, pollution and overuse of external inputs, overharvesting and the proliferation of invasive species. Interactions between drivers often exacerbate their effects on BFA [i.e. biodiversity for food and agriculture]. Demographic changes, urbanization, markets, trade and consumer preferences are reported [by the countries that provided inputs to the report] to have a strong influence on food systems, frequently with negative consequences for BFA and the ecosystem services it provides. However, such drivers are also reported to open opportunities to make food systems more sustainable, for example through the development of markets for biodiversity-friendly products.” It further states that “the driver mentioned by the highest number of countries as having negative effects on regulating and supporting ecosystem services [in food and agricultural production systems] is changes in land and water use and management” and that “loss and degradation of forest and aquatic ecosystems and, in many production systems, transition to intensive production of a reduced number of species, breeds and varieties, remain major drivers of loss of BFA and ecosystem services.”
The 2019 IPBESGlobal Assessment Report on Biodiversity and Ecosystem Services asserts that industrial farming is a significant factor in collapsing biodiversity.
The health of humans is largely dependent on the product of an ecosystem. With biodiversity loss, a huge impact on human health comes as well. Biodiversity makes it possible for humans to have a sustainable level of soils and the means to have the genetic factors in order to have food.
^ abTagliapietra, Davide; Sigovini, Marco. "Biological diversity and habitat diversity: a matter of Science and perception". Terre et Environnement(PDF). 88. pp. 147–155. ISBN2-940153-87-6. Archived from the original(PDF) on 2 February 2017. Retrieved 18 September 2019.
^Gonzalez, Andrew; Cardinale, Bradley J.; Allington, Ginger R. H.; Byrnes, Jarrett; Arthur Endsley, K.; Brown, Daniel G.; Hooper, David U.; Isbell, Forest; O'Connor, Mary I.; Loreau, Michel (2016). "Estimating local biodiversity change: a critique of papers claiming no net loss of local diversity". Ecology. 97 (8): 1949–1960. doi:10.1890/15-1759.1. PMID27859190. two recent data meta-analyses have found that species richness is decreasing in some locations and is increasing in others. When these trends are combined, these papers argued there has been no net change in species richness, and suggested this pattern is globally representative of biodiversity change at local scales
Worm, B.; Barbier, E. B.; Beaumont, N.; Duffy, J. E.; Folke, C.; Halpern, B. S.; Jackson, J. B. C.; Lotze, H. K.; Micheli, F.; Palumbi, S. R.; Sala, E.; Selkoe, K. A.; Stachowicz, J. J.; Watson, R. (2006-11-03). "Impacts of Biodiversity Loss on Ocean Ecosystem Services". Science. American Association for the Advancement of Science (AAAS). 314 (5800): 787–790. Bibcode:2006Sci...314..787W. doi:10.1126/science.1132294. PMID17082450.