Realized Fungal Diversity Increases Functional Stability of Leaf Litter Decomposition Under Zinc Stress

Microbial Ecology - Tập 59 - Trang 84-93 - 2009
Cláudia Pascoal1, Fernanda Cássio1, Liliya Nikolcheva2, Felix Bärlocher2
1CBMA (Centre of Molecular and Environmental Biology), Department of Biology, University of Minho, Braga, Portugal
2Department of Biology, Mount Allison University, Sackville, Canada

Tóm tắt

Freshwaters include some of the most impaired systems on Earth with high rates of species loss, underscoring the significance of investigating whether ecosystems with fewer species will be able to maintain ecological processes. The environmental context is expected to modulate the effects of declining diversity. We conducted microcosm experiments manipulating fungal inoculum diversity and zinc concentration to test the hypothesis that fungal diversity determines the susceptibility of leaf litter decomposition to Zn stress. Realized fungal diversity was estimated by counting released spores and by measuring species-specific biomasses via denaturing gradient gel electrophoresis. In the absence of Zn, positive diversity effects were found for leaf mass loss and fungal biomass through complementary interactions and due to the presence of key species. The variability of leaf decomposition decreased with increasing species number (portfolio effect), particularly under Zn stress. Results suggest that the effect of species loss on ecosystem stability may be exacerbated at higher stress levels.

Tài liệu tham khảo

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