塔里木河下游不同地下水埋深下的土壤种子库特征

The characteristics of the soil seed banks follow different groundwater depth in the lower reaches of Tarim River

本研究根据长期地下水位的监测资料和土壤种子库的萌发试验,分析了塔里木河下游不同地下水埋深下植物样地土壤种子库特征。结果显示,在干旱地区,地下水埋深的高低不仅影响地上植被群落的种类和组成,而且也对土壤种子库的密度和组成具有明显的影响。随着地下水埋深逐渐下降,种子库密度减少、物种多样性下降、生活型逐渐单一。同时地上植被群落与土壤种子库的相似性系数也逐渐降低。本研究不仅有助于丰富国内外关于干旱区土壤种子库的理论研究,而且有利于指导塔里木河下游正在开展的大规模生态恢复实践。

Based on monitoring data of the long-term groundwater depth and soil seed bank experiments, we analyzed the characteristics of soil seed banks with different groundwater depth in the lower reaches of the Tarim River. The groundwater depth influenced not only species composition of the standing vegetation but also the density and species composition of the soil seed banks in the study areas. With declining groundwater depth, the degree of degradation of the standing vegetation had an increasing trend which was reflected by changes in soil seed banks. These changes were characterized by decreased soil seed density, decline of biodiversity and simplification of life style with the increase of groundwater depth. Further, the similarity coefficient between the standing vegetation and the groundwater depth also showed a decreasing trend with the degree of degradation. This study has enriched the theories of soil seed banks in arid areas and can also provide some scientific references for implementing projects of large-scale ecological restoration in the lower reaches of the Tarim River.