不同植物群落对灰岩试块溶蚀速率的影响

Influence of Different Plant Communities On Erosion Rates of Limestone Rock Blocks

用澳大利亚产的微侵蚀计,对湖南郴州礼家洞3个植物群落土壤和泉水中的灰岩溶蚀速率进行了精确测定。对取得的1 650个数据,用SPSS应用软件进行处理,发现乔木群落泉水和土壤中灰岩的平均溶蚀速率最高,分别为3.17 mm/a和0.63 mm/a。在测定灰岩溶蚀速率的同时,对泉水的水化学特征和土壤中的TOC进行了分析,发现乔木群落样地的泉水有更强的溶蚀力(较低的方解石饱和指数和较高的CO2分压)。乔木群落土壤中的TOC比灌丛、草丛的多。与灌丛、草丛相比,乔木群落对CO2汇的贡献最大。

Erosion rates of limestone rock blocks in spring soil of three plant communities at Lijiadong, Chenzhou, Hunan Province were measured with micro-erosion meter made in Australia. After processing 1 650 erosion rate data with SPSS statistical software, it was believed that the average erosion rate of limestone rock blocks in spring water and soil of arbor community were very high with being 3.17 mm/a and 0.63 mm/a. When measuring erosion rates of limestone rock blocks, hydrochemical characteristics of fluids and TOC of soil were analyzed. Results showed that the erosion capacity of fluids in arbor community was stronger （the lower saturation index of calcite and the higher pco2 ） and the content of TOC in arbor community is higher than that in shrub and herb community. Arbor community had more contribution to the sink of atmospheric carbon dioxide than shrubs and herbs.