Plant Diversity and Soil Properties at Different Wetland Restoration Stages along a Major River in the Arid Northwest of China

摘要

Agricultural activity is widely recognized as one of the leading drivers of natural wetland loss in many parts of the world. The suitability of farmland abandonment as the wetland restoration has not been well studied in arid regions. The plant growth, community structure and soil property were examined in three farmlands abandoned for 2 (W2), 6 (W6) and 15 (W15) years and reference wetland (Wr) in the Zhangye National Wetland Park in Gansu province. The results showed that the plant abundance, soil organic carbon, total nitrogen, soil water content increased and pH value decreased along the wetland restoration stages. Shannon-Wiener diversity and Pielou's evenness index moved towards natural wetland with increasing time of farmland abandonment, the plant community composition of the three abandoned farmlands also changed from annual to perennial dominant species. The farmland abandonment is conducive to improve soil nutrients and quality. Soil and vegetation facilitated one another in the abandonment stages. Thus, farmland abandonment is rational for wetland restoration. The mechanism of interaction between plant and soil can be used to guide wetland restoration of abandoned farmland.