Spatial Variations in the Surface Water Chemistry of Subtropical Peatlands (Central China) Linked to Anthropogenic Pressures

Abstract

Abstract:Compared with the extensively surveyed temperate and boreal peatlands, subtropical peatlands have received rather little scientific attention. In this study, spatial variations in water chemistry were investigated in 57 samples collected from three subtropical peatlands (central China). Generally, water pH and major cation concentrations of these samples approached the characteristics of poor fens along the bog-rich fen gradient. Four distinct groups were identified by cluster analysis and principal component analysis. High concentrations of trace elements in Group I were probably linked to airborne dust pollutants from a nearby road under construction. Low pH values and low major cation concentrations in Group II may be attributed to the great cation exchange capacity of Sphagnum. In contrast, samples in Group III, mainly collected from sites suffering from Sphagnum harvest, showed high pH levels and major cation concentrations. Relatively low concentrations of trace elements (except boron) in Group IV can be regarded as reference conditions for restoration efforts in these peatlands. Taken together, spatial variations in the water chemistry of the three peatlands were closely linked to natural processes (e.g., cation exchange of Sphagnum) and anthropogenic pressures (e.g., Sphagnum harvest). Overall, the mean health risk values of the six trace elements were low, indicating good water quality in these peatlands. This study provided baseline water chemistry information for the sustainable management of these subtropical peatlands, as well as other similar ecosystems.

Effects of climate change on a subtropical montane peatland over the last two centuries: Evidence from diatom records

“…E. perpusillum, F. saxonica and E. fallax ), all of which are indicators of very good ecological quality (Lange-Bertalot et al, 2017). In addition, low health risk values for trace elements in surface waters in the Dajiuhu Peatland suggest relatively good water quality (Cao et al, 2017). Taken together, local human activities are unlikely to be the major driving force for changes in diatoms and geochemical elements in the Dajiuhu Peatland.…”

“…BP), peat has developed in this basin to a depth of 2–3 m (Huang et al, 2018). Dajiuhu Peatland is a poor fen, fed by both rainfall and surface runoff from surrounding mountains (Cao et al, 2017). Surface runoff is finally drained through sinkholes to the Duhe River, a tributary of the Danjiangkou Reservoir that is the source water area of the South-to-North Water Transfer Project (Middle Route) of China.…”

Diatom‐inferred microtopography formation in peatlands

“…Furthermore, peatlands at low elevations tend to be influenced by anthropogenic disturbances (e.g. reclamation, drainage and Sphagnum harvest), which probably influence diatom composition and water quality (Cao et al, 2017). Therefore, further studies are needed to explore the underlying linkage between altitude and diatom distribution.…”

Trace elements in peat bog porewaters: indicators of dissolution of atmospheric dusts and aerosols from anthropogenic and natural sources

“…To date, however, there has been little effort to use peat bog porewaters with this stated goal. 24–28 In respect to other published data on TEs in bog waters, early work was restricted to the most abundant trace metals such as Al, Fe, Mn and perhaps Zn, 29–39 with more recent work starting to include the less abundant TEs. 40–45…”