Biology Why is biodiversity so important

Exhibition showcase on biodiversity in the Berlin Natural History Museum

biodiversity or biological Diversity According to the Convention on Biological Diversity (CBD), denotes "the variability among living organisms of all origins, including land, marine and other aquatic ecosystems and the ecological complexes to which they belong". It thus encompasses the diversity within species and the diversity between species as well as the diversity of ecosystems.[1][2] According to this definition, biodiversity also consists of genetic diversity.[3][4][5]

Conservation and sustainable use of biological diversity are considered to be important foundations for human wellbeing. By far the greatest threat to biological diversity on earth is seen in the destruction and fragmentation of habitats.[6] There is no agreement on the question of which biological variability should be preserved and how biodiversity should be parameterized.[7] This disagreement is based on competing biodiversity views and goals that are pursued with the conservation of biodiversity.[8]

On the development of the term and its implications for meaning

Technical term in biology

The term "Diversity"As an ecological technical term to describe the" difference "of the characteristics of communities or ecological systems (α- and γ-diversity, see below). In addition to the number of species, the best-known descriptive measure for diversity is (species richness) the Shannon-Wiener index derived from information theory. It takes into account both the frequency distribution and the diversity of species. Another popular diversity index in biology is the Simpson index.

The diversity of a community in the sense defined here is initially not to be understood as an ecological term of description. Diversity indices cannot simply be used to compare a normatively interpretable nature conservation value of communities.

Term in environmental policy

Biodiversity is the short form of the term biological Diversity (English: biological diversity or biodiversity). The designation biodiversity originally comes from the scientific environment of the US conservation movement. The use of "biodiversity" also in research contexts led to a certain politicization of the scientific research field of nature conservation biology. The establishment of the term should serve to enforce political demands with a social, economic and scientific policy background.[9] The title of the book published in 1986 by evolutionary biologist Edward O. Wilson Biodiversity (English edition) was the first widely perceived use of the term. The book was preceded by a US conference on the subject.

In German-speaking countries, "biodiversity" has been used more and more since the debate about the adoption of the Convention on Biological Diversity (CBD) at the Earth Summit in 1992.

Ambivalent use of language in Germany

Sometimes the term biodiversity used synonymously for biodiversity. However, the definition chosen in the CBD also includes other meanings (see below). In the German-speaking world, the term is generally considered to be "bulky" and difficult to convey to the public. Even the Federal Republic of Germany, the host of the 9th Conference of the Parties in 2008, tried to find a substitute term for the public and called the event the “Nature Conservation Conference”.

Levels, indicators and measures for biodiversity

Biodiversity spans different levels:

  1. genetic diversity - on the one hand the genetic diversity of all genes within a species (= genetic variability), on the other hand the entire genetic diversity of a biocenosis or an ecosystem;
  2. Species diversity - the multitude of species in an ecosystem;
  3. Ecosystem Diversity - the diversity of habitats and ecosystems;
  4. Functional biodiversity - the diversity of realized ecological functions and processes in the ecosystem (for example, assessed on the basis of the number of different types of life or ecological guilds).

A complete characterization of biodiversity must include all four levels.

The CBD has the development of Indicators for biodiversity of the Biodiversity Indicators Partnership transfer.[10] Important indicators are

  • the abundance and distribution of species,
  • the forest area,
  • the area of ​​protected areas (nature reserves, etc.),
  • the water quality of sea and fresh water (eutrophication, pollution, etc.),
  • Number of carriers of traditional natural knowledge by natives.

Due to methodological difficulties, some of these are not measures for biodiversity itself, but rather better known or more easily measurable substitute variables, i.e. H. Indicators (eng .: indicators, proxies).

Whittaker's approach is particularly important for measuring biodiversity in a wider context than that of individual communities. According to Robert H. Whittaker (1960, 1977) species diversity is divided into alpha, beta, gamma, delta and epsilon diversity. These classifications describe diversity patterns depending on the observed area or area distribution patterns.[11][12]

Loss of biodiversity

In 2000, a team of scientists from eight countries identified the five most important influencing factors that mainly cause the decline in global biodiversity:

  • Change in land use. This includes, in particular, the deforestation of forests and the transformation of natural ecosystems into agriculturally used areas.
  • Climate changes, including precipitation and temperature.
  • Nitrogen pollution of waters. Entries about artificial fertilizers, faeces and car exhaust fumes are given the main responsibility here.
  • Introduction of neophytes
  • Increasing the concentration of carbon dioxide in the atmosphere

Suitable measures to counter the decline in biodiversity are the replacement of fossil fuels and wood with alternative energy sources, the enlargement of protected areas to preserve the primary ecosystems, especially in the tropical rainforests, and the preservation of the current diversity in nature and agriculture.[13]

Biodiversity hotspots

For a geographical area in which the biodiversity is particularly large, the term Biodiversity hotspot naturalized. An important study on the designation of the Hot spots was published in 2000 by Myers et al. (2000) presented.[14] The hotspots are described by Myers et al. defined as areas with a high number of endemic plant species, which have already lost most of their original habitat in this area. The criterion of species diversity and that of endangerment, derived from the extent of habitat loss, are therefore used as indicators. Brooks et al. (2001) describe the extent of habitat loss and species extinction in the Hot spots.[15]

Biodiversity and functionality of ecosystems

The importance of biological diversity for the function of ecosystems has been the subject of controversial discussion for several decades. At the end of the 1960s, these discussions reached an initial consensus: diversity favors stability.[16][17] However, this consensus was severely disrupted a short time later when Robert May, using mathematical simulations, came to the conclusion that species constancy in randomly composed species-rich model ecosystems is lower than in species-poor model ecosystems.[18] The constancy of the species composition was considered to be the most important indicator of the stability of an ecosystem at the time. The results of David Tilman, published from the mid-1980s, brought an intensive re-engagement with the question of diversity and stability.[19] The question of the importance of biodiversity for the functionality of ecosystems is a focus of ecosystem research and nature conservation ecology. The following scientific consensus applies today:[20]

  • The functional properties of species have a strong influence on the properties of an ecosystem. The importance of this species for the ecosystem cannot always be derived from the relative abundance of a species alone. Even relatively rare species can have a major impact on the nature of the ecosystem.
  • Some species, often dominant ones, play a decisive role within the biological communities (so-called key species). Their loss leads to drastic changes in terms of the structure and function of the community.[21]
  • The effects of species extinction and changes in species composition can vary in terms of the nature of the ecosystem, the type of ecosystem, and the way the change is expressed in the community.
  • Some properties of ecosystems are initially less susceptible to species extinction, as several species may fulfill a similar function within an ecosystem (redundancy), individual species may contribute relatively little to the functionality of an ecosystem ('irrelevance'), or abiotic environmental conditions may affect the nature determine the ecosystem.
  • With increasing spatial and temporal variability, the number of species necessary for the function of ecosystems increases.

The following is considered likely:

  • The susceptibility of a community to the establishment of neobiota correlates negatively with the number of species, with the 'saturation' of the community. But it also depends on other factors such as the rate of introduction of diaspores (propagule pressure), Disruptive factors or resource availability.
  • If existing species react differently to disruptive factors, then the function of the ecosystem is more likely to be preserved in the event of disruptive influences than if the existing species react similarly to disruptive factors.

Economic and social importance of biodiversity

The CBD affirms the value of biological diversity and its components with regard to ecological, genetic, social, economic, scientific, educational, cultural and aesthetic contexts as well as with regard to the recreational function and, in addition to the instrumental aspects, acknowledges the intrinsic value of biodiversity.[22]

Self worth and self worth

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Intrinsic value means that biodiversity is valued in itself because of the value that people attach to it.[23] This appreciation concerns z. B. their existence per se, their personal and cultural significance for the individual in terms of memory value and home, their special character or the possibility of conveying special experiences to the individual, such as that of the wilderness. From the point of view of the ecosystem service approach, the elements, structures, states and processes of ecological systems to which intrinsic values ​​are ascribed are mostly understood as cultural ecosystem services.[24]

The self-worth of biodiversity must be distinguished from intrinsic value. Under Self worth According to Uta Eser, biodiversity is the intrinsic value of biodiversity. Objects with self-worth have a purpose in and of themselves, cannot be replaced, are generally not subject to any consideration and cannot be monetized. From the aspect of the self-worth of biodiversity, concepts are to be preferred which consider the conservation of biodiversity per se, i.e. which do not apply the standard solely to the maintenance of its functions. Whether one can ascribe self-worth to biodiversity or the creatures that make it up is very controversial.

Insurance hypothesis and insurance value

After ecological insurance hypothesis (Ecological Insurance Hypothesis)[25] It can be expected that an increase in the number of species (and / or the genetic variability within the populations of a species) has a stabilizing effect on various process parameters of ecological systems. As the number of species increases, the likelihood of multiple species occurring that can perform a very similar ecological function increases (functional redundancy), but differ in their environmental tolerances. This reduces the probability that changes in environmental conditions will cause all species that can fulfill the function in question to locally become extinct.[25][26]

A high number of species is also a condition for a large number of different ecological functions to be able to be performed in an ecosystem (functional diversity). If the environmental conditions change, a previously insignificant function can become relevant. If, for example, an ecosystem that was previously extensively supplied externally with reactive nitrogen compounds is cut off from the nitrogen source, the importance of nitrogen-fixing organisms increases. In a species-rich ecosystem, there is a higher probability that species already exist that can perform this function. In the case of species-rich ecosystems, it is also assumed that the food web relationships are more stable.[27]

If biological diversity - in accordance with the ecological insurance hypothesis or similar mechanisms - stabilizes processes and conditions of ecological systems, biodiversity can have a Insurance value be assigned. This is at least always the case when ecosystem services depend on the processes and conditions. A high level of biodiversity therefore tends to make ecosystem services more reliable.[28] From an environmental point of view, the insurance value is an option value in the face of an uncertain future, since the extent of future disruptions that require stabilization is not known.

Attempts can be made in various ways to economically estimate the insurance value. One method takes into account the susceptibility of the processes and structures of the ecosystem to failure and determines the impact of this on the provision of ecosystem services.[29] Since the insurable value here is essentially derived from the behavior of ecological systems in the event of disruptions, economic quantification can be difficult.[30] Changes caused by disturbances often have no linear effect on the provision of ecosystem services. Rather, major changes often only take place when a certain threshold, the so-called "tipping point", is exceeded. The probability that tipping point can be used as a guide to the economic value. In-depth knowledge of the current status of the system, its prerequisites and its specific tipping point areas are required for the assessment on which the insured value is based.[29] See also stability concepts of ecosystems, especially that of resilience.[31]

Another method for the economic quantification of the insurance value makes a direct determination of the population's willingness to pay. Social science survey methods are used (stated preference methods) like the contingent assessment or the choice experiment. Evidence that such an insurance value is recognized by the population as an economic preference in the sense of willingness to pay is now available through several studies from Indonesia, Chile and Germany. [32][33][34] Another method is the observation of the decision-making behavior of land users. It has been shown that farmers appreciate the advantage that a reduced fluctuation range of the annual harvest yield with higher agrobiodiversity brings with it: They then prefer to grow different crops (crop diversity) at.[35] The agronomic value of the crop diversity however, it is limited by opposing specialization advantages.[36]

Value to pharmacy and breeding

Biodiversity is also of economic importance as a reservoir of potential active pharmaceutical ingredients and genes for agricultural variety breeding, for biotechnological processes or for bionic developments (option value).

While in the past interested scientists and company representatives could freely use the biodiversity of foreign countries ("Biopiracy"), the Biodiversity Convention introduced a state's ownership rights to its genetic resources. A mechanism called Access and Benefit Sharing (ABS) tries to facilitate the use of genetic resources while at the same time allowing the source countries of biodiversity to participate in their economic use.

Maintaining health

The decline in biodiversity can increase the prevalence of infectious diseases in an ecosystem.[37] The spread of pathogens such as viruses, bacteria and pathogenic fungi is promoted. The health of people, but also of remaining animals and plants, can be endangered as a result.

Social aspects of biodiversity loss

In many cases, the consequences of decreasing biodiversity hit the poor rural population first, as they are often directly dependent on ecosystem services, which in turn are based on a diverse biological environment or the sustainable use of its elements. Replacements for these ecosystem services are often inaccessible or affordable for these parts of the population.[38]

Protection of biological diversity

Suitable measures to counter the decline in biodiversity are the replacement of fossil fuels and wood with alternative energy sources, the enlargement of protected areas to preserve the primary ecosystems, especially in the tropical rainforests, and the preservation of the current diversity in nature and agriculture.[13]

Conventions

The UN Convention on Biological Diversity (CBD), which was adopted and signed by 192 member states at the 1992 Earth Summit in Rio de Janeiro, provides a basis for protecting biodiversity. Other international agreements for the protection of biological diversity are the Ramsar Convention and the Washington Convention on the Protection of Species (CITES). In the CBD, the member states have committed to stop the loss of biological diversity. The three main goals are: The protection of biodiversity, its sustainable use and the fair compensation of the benefits resulting from the use of (genetic) resources.

Official strategies

Germany

In 2007 the federal government adopted a national strategy on biological diversity. In doing so, she is implementing an order from the CBD. The strategy names 330 goals and around 430 measures and is to apply by 2020. In essence, the decline in biological diversity should be halted. The Bundestag is regularly informed about the implementation of the strategy.

European Union

On May 2, 2011, the European Commission published its own biodiversity strategy with which it aims to stop the loss of biological diversity by 2020.[39] The strategy has six objectives:

    1. the full implementation of Directive 92/43 / EEC (Fauna-Flora-Habitat Directive) from 1992.
    2. the preservation and enhancement of ecosystems.
    3. to increase the contribution of agriculture and forestry to the conservation and enhancement of ecosystems.
    4. to ensure the sustainable use of fish stocks.
    5. identify and control the spread of invasive species.
    6. to help stop the global loss of biodiversity.[40]

miscellaneous

  • The United Nations has that International Biodiversity Day Since 2000, it has been set to May 22nd, the date on which the Convention was adopted (previously, since 1994, December 29th, the date of its entry into force).
  • The year 2010 was recognized by the UN as International Year of Biodiversity called out.

See also

  • Biodiversity of the Philippines
  • Key biodiversity areas

Recent literature

  • Bruno Baur: Biodiversity. UTB, Bern 2010, ISBN 978-3-8252-3325-9 (UTB 3325, UTB profiles).
  • Federal Agency for Nature Conservation: Data on nature 2008.(Series of publications on the state of nature in Germany and on measures taken to conserve biodiversity), Landwirtschaftsverlag, Münster 2008, ISBN 978-3-7843-3858-3.
  • Federal Agency for Nature Conservation (ed.), Thomas Potthast (editing): Biodiversity - a key concept for nature conservation in the 21st century? Federal Agency for Nature Conservation, Bonn-Bad Godesberg 2007.
  • Forum Biodiversity Switzerland: Biodiversity in Switzerland. State, conservation, prospects. Scientific basis for a national strategy. Haupt, Bern 2004, ISBN 3-258-06800-3.
  • Kevin J. Gaston, John I. Spicer: Biodiversity. An Introduction. 2nd edition, reprint. Blackwell, Malden MA 2005, ISBN 1-4051-1857-1.
  • Carsten Hobohm: Biodiversity. Quelle & Meyer, Wiebelsheim 2000, ISBN 3-8252-2162-8 (UTB 2162 Biology, ecology).
  • Peter Janich, Mathias Gutmann, K. Prieß: Biodiversity. Scientific basis and legal relevance. Springer, Berlin 2001.
  • Thomas E. Lovejoy, Lee Jay Hannah (Eds.): Climate Change and Biodiversity. Yale University Press, New Haven CT 2006, ISBN 0-300-11980-1.
  • Josef H. Reichholf: End of biodiversity? Endangerment and destruction of biodiversity. Edited by Klaus Wiegandt. Fischer-Taschenbuch-Verlag, Frankfurt am Main 2008, ISBN 978-3-596-17665-6 (Fisherman 17665).
  • Bruno Streit: What is biodiversity? Exploration, protection and value of biological diversity. Beck, Munich 2007, ISBN 978-3-406-53617-5.

Web links

Template: Commonscat / WikiData / Difference

Individual evidence

  1. ↑ Wording of the CBD (German version). Quote from Article 2 (PDF).
  2. ↑ This convention becomes binding for a state when it is ratified.
  3. ↑ United Nations: Multilateral Convention on biological diversity (with annexes). Concluded at Rio de Janeiro on June 5, 1992. In: United Nations Treaty Series Vol. 1760, p. 146 (Article 2. Use of Terms). (PDF). German translation under: Definitions, Art. 2 of SR 0.451.43 Convention on Biological Diversity. As of March 20, 2007.
  4. ↑ Wilson, E. O .: End of Biodiversity? The loss of species, genes, and habitats and the chances of reversal. Spektrum, Heidelberg, Berlin, New York, 1992, ISBN 3-89330-661-7.
  5. ^ Controversy, B .: What is biodiversity? Exploration, protection and value of biological diversity. Beck, Munich 2007.
  6. ↑ Thomas M. Smith, Robert L. Smith: Ecology, Pearson Studium Verlag, ISBN 978-3-8273-7313-7, p. 818 f.
  7. ^ Peter Janich, Mathias Gutmann: Normative foundations of biodiversity. In: W. Barthlott & M. Gutmann (eds.): Biodiversity Research in Germany. Potentials and perspectives. European Academy, Bad Neuenahr-Ahrweiler 1998: pp. 66–72.
  8. ↑ Thomas Kirchhoff, Ludwig Trepl: On the value of biodiversity. About competing political theories in the discussion about biodiversity. Journal for Applied Environmental Research 2001 / S13: pp. 27–44; Uta Eser: The value of diversity: 'Biodiversity' between science, politics and ethics. In: M. Bobbert, M. Düwell, K. Jax (eds.): Environment - ethics - law. Francke, Tübingen, 2003: pp. 160-181; Stefan Baumgärtner: Why measurement and assessment of biological diversity are not possible independently of one another. In: J, Weimann, A. Hoffmann, S. Hoffmann (eds.): Measurement and economic evaluation of biodiversity: Mission impossible? Metropolis, Marburg: 2003: pp. 43-66; Thomas Potthast: What is biodiversity and why should it be preserved? Philosophical and ethical perspectives. In: Stiftung Natur und Umwelt Rheinland-Pfalz (ed.): Food for thought, Volume 2: Theses on biodiversity. 2005: pp. 18-29; Thomas Kirchhoff & Sylvia Haider: Global multitude or local diversity: on the cultural ambivalence of 'biodiversity'. In: T. Kirchhoff, L. Trepl (eds.): Ambiguous nature. Landscape, wilderness and ecosystem as cultural-historical phenomena. transcript, Bielefeld 2009: pp. 315-330; Kristian Köchy: Is diversity a value? On the current debate about biodiversity. In: C. F. Gethmann (ed.): German Yearbook Philosophy, Volume 2: Lifeworld and Science. Meiner, Hamburg: pp. 1227-1248.
  9. ↑ Reinhard Piechocki: Landscape - home - wilderness: protection of nature - but which one and why? Beck, Munich 2010.
  10. ↑ The homepage of the provides an overview of the status of the indicator development Biodiversity Indicators Partnership.
  11. ↑ www.redpath-museum.mcgill.ca [1]
  12. ↑ www.gap.uidaho.edu [2]
  13. 13,013,1Thomas M. Smith, Robert L. Smith: Ecology, Pearson Studium Verlag, ISBN 978-3-8273-7313-7, p. 645 ff.
  14. ↑ Norman Myers, Russell A. Mittermeier, Cristina G. Mittermeier, Gustavo A. B. da Fonseca & Jennifer Kent: Biodiversity hotspots for conservation priorities. Nature 403 (2000), pp. 853-858 available online
  15. ↑ Thomas M Brooks et al .: Habitat loss and extinction in the hotspots of biodiversity. Conservation Biology 16 (2002), pp. 909-923; available online
  16. ↑ cf. Results of the Brookhaven Symposia in Biology at which this point of view was “codified”: Diversity and Stability in Ecological Systems. Woodwell, G.M .; Smith, H.H. (Ed.) 1969. Brookhaven Symposia in Biology No. 22, Brookhaven National Laboratory, Upton, NY.
  17. ↑ See also Kevin Shear McCann (2000) The diversity-stability debate. Nature 405, 228-233. doi: 10.1038 / 35012234
  18. ↑ Robert M. May (1973) Stability and complexity in model ecosystems. Princeton Univ. Press
  19. ↑ Kevin Shear McCann (2000): The diversity-stability debate. Nature 405: pp. 228-233. doi: 10.1038 / 35012234
  20. ↑ D. U. Hooper, FS Chapin, III, JJ Ewel, A. Hector, P. Inchausti, S. Lavorel, JH Lawton, DM Lodge, M. Loreau, S. Naeem, B. Schmid, H. Setälä, AJ Symstad, J Vandermeer, DA Wardle (2005): Effects of Biodiversity on Ecosystem Functioning: A Consensus of Current Knowledge. Ecological Monographs 75 (1): pp. 3-35. [3]
  21. ↑ Thomas M. Smith, Robert L. Smith: Ecology, Pearson Studium Verlag, ISBN 978-3-8273-7313-7, p. 480 f.
  22. ↑ according to the CBD (German version). (PDF)
  23. ↑ The terms “Eigenwert” and “Selbstwert” are explained in somewhat more detail in: Uta Eser & Thomas Potthast: Conservation ethics. An introduction to practice. Nomos Verlagsgesellschaft, Baden-Baden 1999. ISBN 3-7890-6016-X. P. 60 ff.
  24. ↑ Terry C. Daniel, Andreas Muhar, Arne Arnberger, Olivier Aznar, James W. Boyd, Kai MA Chan, Robert Costanza, Thomas Elmqvist, Courtney G. Flint, Paul H. Gobster, Adrienne Grêt-Regamey, Rebecca Lave, Susanne Muhar , Marianne Penker, Robert G. Ribe, Thomas Schauppenlehner, Thomas Sikor, Ihor Soloviy, Marja Spierenburg, Karolina Taczanowska, Jordan Tam, and Andreas von der Dunk (2012) Contributions of cultural services to the ecosystem services agenda. Proceedings of the National Academy of Sciences 109 (23): 8812-8819
  25. 25,025,1Shigeo Yachi and Michel Loreau: Biodiversity and ecosystem productivity in a fluctuating environment: The insurance hypothesis. Proceedings of the National Academy of Science USA 96 (1999): 1463-1468 [4]
  26. ↑ cf. Pieter J. den Boer: Spreading of risk and stabilization of animal numbers. Acta Biotheoretica 1968/18 (1-4): pp. 165-194.
  27. ^ McCann, K. S .: The diversity-stability debate. Nature 2000/405: pp. 228-233.
  28. ↑ R. Marggraf: Economic aspects of biodiversity assessment. Peter Janich, Mathias Gutmann & K. Priess: Biodiversity - Scientific principles and social relevance. Springer, Berlin: pp. 355-411; Sandra Rajmis: Appreciation of biodiversity as a source of ecological insurance benefits in Germany. In: Federal Agency for Nature Conservation (ed.): Meeting point for biological diversity VI. Current research under the Convention on Biological Diversity. Federal Agency for Nature Conservation, Bonn-Bad Godesberg: pp. 143-148; Stefan Baumgärtner: The insurance value of biodiversity in the provision of ecosystem services. Natural Resource Modeling 2007/20 (1): pp. 87-127.
  29. 29,029,1Lasse Loft, Alexandra Lux: Ecosystem Services - Economic analysis of their loss, their evaluation and control Project area transfer of results and socio-ecological aspects of climate-related changes in biodiversity, Institute for Social-Ecological Research (ISOE)
  30. ↑ Stefan Baumgärtner: The insurance value of biodiversity in the provision of ecosystem services. Natural Resource Modeling 2007/20 (1): pp. 87-127.
  31. ↑ See e.g. Crawford S. Holling: Resilience and stability of ecological systems. Annual Review of Ecology and Systematics 1973/4: pp. 1-23.
  32. ↑ Jan Barkmann, Klaus Glenk, Handian Handi, Leti Sundawati, Jan-Patrick Witte, Rainer Marggraf (2007): Assessing economic preferences for biological diversity and ecosystem services at the Central Sulawesi rainforest margin - a choice experiment approach. In: Teja Tscharntke, Christoph Leuschner, Manfred Zeller, Edi Guhardja, Arifuddin Bidin (Eds.) Stability of Tropical Rainforest Margins. Linking ecological, economic and social constraints of land use and conservation. Springer, Berlin, pages 181-208.
  33. ↑ Claudia Cerda, Iason Diafas, Jan Barkmann, John Mburu, Rainer Marggraf (2007): WTP or WTA, or both? Experiences from two choice experiments for early planning stages. In: Jürgen Meyerhoff, Nele Lienhoff, Peter Elsasser (Eds.) Stated Preference Methods for Environmental Valuation: Applications from Austria and Germany. Metropolis Verlag, Marburg, pages 139-173.
  34. ^ Sandra Rajmis, Jan Barkmann, Rainer Marggraf: Pythias Rache: on the economic value of ecological risk management. GAIA 2010/19 (2): pp. 114-121.
  35. ^ Salvatore Di Falco, Charles Perrings (2003) Crop Genetic Diversity, Productivity and Stability of Agroecosystems. A Theoretical and Empirical Investigation. Scottish Journal of Political Economy 50 (2): 207-216.
  36. ^ Jean-Paul Chavas, Salvatore Di Falco (2012) On the Productive Value of Crop Biodiversity: Evidence from the Highlands of Ethiopia. Land Economics 88: 58-74
  37. Keesing, F. et al .: Impacts of biodiversity on the emergence and transmission of infectious diseases. In: Nature. 468, No. 7324, 2010, pp. 647-652. PMID 21124449.
  38. ↑ cf. the UN biodiversity report points 5 and 7.
  39. More than flowers and bees. The EU biodiversity strategy Press portal Europe on site. Communication dated May 3, 2011.
  40. Questions and answers on the EU biodiversity strategy (in English) EU press release of May 3, 2011.