Human impact on peatlands : from biogeochemical issues towards sustainable and use options

The debates about the pros and cons of cloning in the media are usually dominated by views of the Christian churches, philosophers, and lobbyists. Yet the issues raised by cloning are, for several reasons, affecting mankind in general and therefore cannot be solved by representatives and opinion leaders predominantly from the so-called 'West' only. Among these reasons is the fundamental question of whether our concepts of 'man', 'personhood', and consequently 'mankind' have to be reformulated in the light of recent scientific progress. It is obvious that a final, universally acceptable answer to this question cannot be arrived at if representatives of religions such as Islam, Buddhism, or Hinduism are not included in this debate

Mesotrofe verlanding en behoud van trilvenen

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Correction: New insights into phosphorus mobilisation from sulphur-rich sediments: Time-dependent effects of salinisation (vol 9, e111106, 2014)

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Plasdras: balans tussen weidevogel, landbouw en waterkwaliteit. Synthese onderzoeksresultaten plasdras Noord-Holland en Utrecht

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Towards more sustainable hydrological management and land use of drained coastal peatlands - A biogeochemical balancing act

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New insights into phosphorus mobilisation from sulphur-rich sediments: Time-dependent effects of salinisation

Internal phosphorus (P) mobilisation from aquatic sediments is an important process adding to eutrophication problems in wetlands. Salinisation, a fast growing global problem, is thought to affect P behaviour. Although several studies have addressed the effects of salinisation, interactions between salinity changes and nutrient cycling in freshwater systems are not fully understood. To tackle eutrophication, a clear understanding of the interacting effects of sediment characteristics and surface water quality is vital. In the present study, P release from two eutrophic sediments, both characterized by high pore water P and very low pore water iron (Fe(2+)) concentrations, was studied in a long-term aquarium experiment, using three salinity levels. Sediment P release was expected to be mainly driven by diffusion, due to the eutrophic conditions and low iron availability. Unexpectedly, this only seemed to be the driving mechanism in the short term (0-10 weeks). In the long term (>80 weeks), P mobilisation was absent in most treatments. This can most likely be explained by the oxidation of the sediment-water interface where Fe(2+) immobilises P, even though it is commonly assumed that free Fe(2+) concentrations need to be higher for this. Therefore, a controlling mechanism is suggested in which the partial oxidation of iron-sulphides in the sediment plays a key role, releasing extra Fe(2+) at the sediment-water interface. Although salinisation was shown to lower short-term P mobilisation as a result of increased calcium concentrations, it may increase long-term P mobilisation by the interactions between sulphate reduction and oxygen availability. Our study showed time-dependent responses of sediment P mobilisation in relation to salinity, suggesting that sulphur plays an important role in the release of P from FeSx-rich sediments, its biogeochemical effect depending on the availability of Fe(2+) and O2

Differential responses of two wetland graminoids to high ammonium at different pH values

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Pitrus, l'enfant terrible van het natte natuurbeheer? : Lastige beheersvragen in de Nederlandse veenweiden

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