An ecosystem health assessment method integrating geochemical indicators of soil in Zoige wetland, southwest China

Abstract

Scientific assessment of the health of wetland ecosystem is an important prerequisite for wetland management and protection. The Zoige wetland ecosystem is a cold peat wetland ecosystem on the eastern edge of the Tibetan Plateau in southwest China. By measuring organic matter and nutrients from soil samples in the Zoige wetland, we found that there were connections between organic matter in soil and vegetation growth, since decomposition of soil organic matter was an important source of soil nutrients and was influenced by the soil water content of the wetland. We therefore integrated a cluster of geochemical indicators of soil, including organic matter content, total nitrogen, total phosphorus content, total potassium content and humic acid yield, into a conceptual framework for ecosystem health assessment, therefore improving the existing indicator system for the Zoige wetland. We analyzed levels of organic matters and nutriment elements in soil samples from the Zoige wetland simultaneously with other indicators of the assessment system. Compared with the previous assessment work for Zoige wetland, the proposed assessment system showed a more holistic result.