Aquatic biodiversity - a forgotten asset?

Eawag News 69e,  August 2010

complete issue [pdf, 2.8MB]

Cause for concern: silent loss of freshwater diversity
Jukka Jokela

In focus: Aquatic biodiversity - a forgotten asset?

Biodiversity - facts, myths, prospects
Mark Gessner
Rivers, lakes and wetlands are particularly species-rich ecosystems. But this diversity is seriously threatened, and effective measures that ensure biodiversity persistence are urgently needed. To be successful, such efforts must be based on an integrative and comprehensive strategy. With the revision of the Swiss Federal Water Protection Act and the development of a national biodiversity strategy, Switzerland is sending clear signals in the right direction. [...]


Influence of habitat diversity on species richness
Interview with Armin Peter and Klement Tockner
Swiss rivers are highly degraded as a result of engineering measures, with monotonous habitats fragmented by artificial barriers. But biodiversity is associated with richly structured ecosystems, such as braided channels or alluvial zones. So what can be done to promote diversity, particularly of fish fauna? We discussed this question with fish ecologist Armin Peter and floodplain expert Klement Tockner. [...]

Microbial diersity - unseen variety
Helmut Bürgmann
The diversity of microorganisms exceeds that of higher organisms in many ecosystems. In addition, microorganisms play a key role in vital ecosystem processes. Should microbial diversity therefore receive more attention – or even be protected? [...]

Functional diversity in wastewater treatment
Eberhard Morgenroth
Variations in influent loads pose major challenges for biological wastewater treatment. Could increased biodiversity allow for more stable operation, and does this mean that biodiversity should also be protected in wastewater treatment plants? Using molecular biological methods, we can now quantify biodiversity and specific groups of microorganisms in complex systems. [...]

The rise and fall of species diversity
Ole Seehausen
The preservation of biodiversity requires a dynamic equilibrium in which speciation occurs just as often as species extinction. But conservation efforts frequently ignore the need to maintain not only the existing diversity of species but also the variety of speciation processes. [...]

Invasive species - threats to diversity?
Kirstin Kopp
Invasive alien species are a major cause of declines in native biodiversity in both terrestrial and aquatic ecosystems. As well as traditional monitoring programmes, genetic methods are now providing valuable information on new arrivals. [...]

Environmental influences and plankton dynamics
Piet Spaak
Anthropogenic environmental changes affect natural biodiversity. This can also be seen in lake phyto- and zooplankton, with water fleas (Daphnia spp.) reacting particularly sensitively. For this reason, they have been used as model organisms in research. [...]

A biodiversity strategy for Switzerland
Evelyne Marendaz
Biodiversity is a vital resource. The preservation and promotion of biological diversity is therefore a fundamental social duty and an economic necessity. At the national level, the Federal Office for the Environment is currently developing a biodiversity strategy on behalf of the Federal Council. [...]



In Brief