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采用雨量器、滤膜法、CO2气体监测管法、标准试片对湘西洛塔不同生态系统降雨量、泥沙量、土壤CO2浓度、溶蚀速度进行了研究。结果表明:森林生态系统降雨量高于灌丛生态系统,观测第一年高6.84mm,第二年高218.08mm,且时间趋向均匀;灌丛生态系统水土流失严重,其泥沙含量是森林生态系统的1.53倍,土壤侵蚀为强度,而森林生态系统为微度;不同深度土壤CO2浓度在森林和灌丛生态系统中具有相同的变化趋势,在春季、秋季、冬季随土层加深而增大,在夏季,随土层加深先减少后增大,但季节变化动态略有差异,森林生态系统不同深度、不同季节土壤CO2浓度均大于灌丛生态系统;从全年土壤CO2浓度对比来看,10、20、40cm处,森林生态系统分别是灌丛生态系统的1.66、1.59和1.90倍;不同深度上,溶蚀速度在森林和灌丛生态系统具有相同的变化趋势,15cm处均大于地面,从同一深度来看,森林生态系统溶蚀速度均大于灌丛生态系统,地面、15cm处溶蚀速度分别是灌丛生态系统的1.11倍、2.57倍,说明森林生态系统具有较好的岩溶效应。
The precipitation, sediment concentration, soil CO2 concentration and erosion rate in different ecosystems of Lota west Hunan Province were studied by means of rain gauge, filter membrane method, CO2 gas monitoring tube method and standard test strip. The results showed that the rainfall in forest ecosystem was higher than that in shrub ecosystem. The observation height was 6.84mm in the first year and 218.08mm in the second year, and the time tended to be even. The soil erosion of the shrub ecosystem was serious, and the sediment content was the forest ecology 1.53 times as much as the soil erosion rate, while the forest ecosystem is slightly different. The soil CO2 concentrations at different depths have the same trend in the forest and shrub ecosystems, and increase with the deepening of soil depth in spring, autumn and winter In the summer, the soil depth decreased first and then increased, but the seasonal variation was slightly different. The soil CO2 concentrations in different depths of forest ecosystem and in different seasons were all greater than those in shrub ecosystems. From the comparison of soil CO2 concentrations in the whole year, At the depths of 10, 20 and 40 cm, the forest ecosystems were 1.66, 1.59 and 1.90 times higher than the scrub ecosystems. At different depths, the erosion rate had the same trend in forest and shrub ecosystems, At the same depth, the erosion rate of forest ecosystems is greater than that of shrub ecosystems, and the erosion rates at 15cm are 1.11 times and 2.57 times higher than that of shrub ecosystems, respectively, indicating that forest ecosystems have more Karst effects.