Variations in diatom communities at genus and species levels in peatlands (central China) linked to microhabitats and environmental factors.
Peatlands are a specialized type of organic wetlands, fulfilling essential roles as global carbon sinks, headwaters of rivers and biodiversity hotspots. Despite their importance, peatlands are being lost at an alarming rate due to human disturbance and climatic variability. Both the scientific and regulatory communities have focused considerable attention on developing tools for assessing environmental changes in peatlands. Diatoms are widely used in biomonitoring studies of lakes, rivers and streams as they have high abundance, specific ecological preferences and can respond rapidly to environmental change. However, diatom-based assessment studies in peatlands remain limited. The aims of this study were to identify indicator species and genus for three types of habitats (hummocks, hollows and ditch edges) in peatlands (central China), to examine the effects of physiochemical factors on diatom composition at genus and species levels, and to compare the efficiency of species- and genus-level identification in environmental assessment. Our results revealed that hummocks were characterized by drought-tolerant diatoms, while hollows were dominated by species and genus preferring wet conditions. Ditch edges were characterized by diatoms with different life strategies. Depth to water table, redox potential, conductivity and calcium were significant predictors of both genus- and species-level composition. According to ordination analyses, pH was not correlated with species composition while it was a significant factor associated with genus-level composition. Genus-level composition outperformed species composition in describing the response of diatoms to environmental variables. Our results indicate that diatoms can be useful environmental indicators of peatlands, and show that genus-level taxonomic analysis can be a potential tool for assessing environmental change in peatlands.
State Key Laboratory of Biogeology and Environmental Geology, School of Earth Sciences, China University of Geosciences, Wuhan, China. Electronic address: xuchen@cug.edu.cn.
Xu
X
Chen
Institute for Peat and Mire Research, State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, Northeast Normal University, Changchun, China. Electronic address: buzhaojun@nenu.edu.cn.
Zhaojun
Z
Bu
School of Geography, University of Nottingham, Nottingham, UK.
Mark A
MA
Stevenson
College of Resources and Environmental Science, South-Central University for Nationalities, Wuhan, China.
Yanmin
Y
Cao
State Key Laboratory of Biogeology and Environmental Geology, School of Earth Sciences, China University of Geosciences, Wuhan, China.
Linghan
L
Zeng
State Key Laboratory of Biogeology and Environmental Geology, School of Earth Sciences, China University of Geosciences, Wuhan, China.
Bo
B
Qin
D058448:Biota; D002681:China; D017377:Diatoms / Q000145:classification / Q000502:physiology*; D064308:Ecological Parameter Monitoring / Q000379:methods*; D004784:Environmental Monitoring / Q000379:methods*; D053833:Wetlands
Biomonitoring; Diatom; Environmental gradient; Genus-level composition; Subtropical peatland