13.9. Vrba

Keynote Presentations from the 3rd ALTER-Net Summer School, Peyresq 2 - 14 September 2008

Speaker: Jaroslav Vrba

jaroslav.vrba -at- prf.jcu.cz

Department of Ecosystem Biology, Faculty of Science, University of South Bohemia, Branišovská 31, CZ-37005 České Budějovice, Czech Republic http://www.prf.jcu.cz/en/; and

Biology Centre AS CR, v.v.i., Institute of Hydrobiology, Na Sádkách 7, CZ-37005 České Budějovice, Czech Republic, vrba -at- hbu.cas.cz, http://www.hbu.cas.cz/

Title of the talk: Ecological stoichiometry - a bottleneck for biodiversity and ecosystem services (pdf: 3MB)

Summary of the talk by Jan Hanspach: Students´ summary (pdf)

Abstract

Elemental stoichiometry entirely controls both occurrence and growth of any organism. This matter of fact, though largely neglected in biology and nature conservation so far, represents a natural driver of biodiversity. Ecological stoichiometry is a new concept that describes the biology of elements from biomolecules to the biosphere. This concept first emerged in oceanography over 70 years ago and soon became a part of limnology. For half a century, the Redfield’s ratio (C:N:P) has been a vivid component of plankton ecology. Current ecologists generally are recognising that the way that nutrients cycle through atmospheric, terrestrial, oceanic and associated biotic reservoirs can constrain rates of biological production and help structure ecosystems on land and in the sea. While a classical view in ecology is based on energetics, ecological stoichiometry unifies it with a “complementary” view based on matter. Following the law of conservation of matter, ecological stoichiometry is an essential advance in unifying ecology across levels of organisation. It examines fundamental chemical constrains of ecological phenomena such as competition, herbivory, symbiosis, energy flow in food webs, and organic matter sequestration. An understanding of the biochemical deployment of element in organisms provides the key to making sense of both aquatic and terrestrial ecosystems. Thus the stoichiometry of resources always should be considered as both key natural driver and anthropogenic pressure of biodiversity. At same time, ecological stoichiometry causes a critical bottleneck for ecosystem services, such as food or timber production, water quality, pollution control, carbon dioxide sequestration, etc.

Recommended background literature on this presentation:

• Arrigo KR (2005) Marine microorganisms and global nutrient cycles. Nature 437:349–355, doi:10.1038/nature04159
• Cleveland CC, Liptzin D (2007) C:N:P stoichiometry in soil: is there a “Redfield ratio” for the microbial biomass? Biogeochemistry 85:235–252, doi:10.1007/s10533-007-9132-0
• Evans-White MA, Stelzer RS, Lamberti GA (2005) Taxonomic and regional patterns in benthic macroinvertebrate elemental composition in streams. Freshwater Biol 50:1786–1799, doi:10.1111/j.1365-2427.2005.01455.x
• Hessen DO (2006) Determinants of seston C:P-ratio in lakes. Freshwater Biol 51:1560–1569, doi:10.1111/j.1365-2427.2006.01594.x
• Sterner RW, Elser JJ (2002) Ecological stoichiometry: the biology of elements from molecules to the biosphere. Princeton University Press, Princeton, 439 pp http://press.princeton.edu/

• Schade JD, Espeleta JF, Klausmeier CA, McGroddy ME, Thomas SA, Zhang L (2005) A conceptual framework for ecosystem stoichiometry: balancing resource supply and demand. Oikos 109:40-51, doi:10.1111/j.0030-1299.2005.14050.x
• Ptacnik R, Jenerette GD, Verschoor AM, Huberty AF, Solimini AG, Brookes JD (2005) Applications of ecological stoichiometry for sustainable acquisition of ecosystem services. Oikos 109:52-62, doi:10.1111/j.0030-1299.2005.14051.x
• Güsewell S, Bailey KM, Roem WJ, Bedford BL (2005) Nutrient limitation and botanical diversity in wetlands: can fertilisation raise species richness? Oikos 109:71-80, doi:10.1111/j.0030-1299.2005.13587.x
• Jeyasingh PD, Weider LJ (2007) Fundamental links between genes and elements: evolutionary implications of ecological stoichiometry. Molecular Ecology 16:4649–4661, doi:10.1111/j.1365-294X.2007.03558.x