贵州省岩溶区水土流失、石漠化受岩溶环境制约

目的研究不同土地类型下喀斯特土下溶蚀速率及其主要影响因素。方法采用野外布点采样、实验室测定和地统计学分析相结合的方法，定量研究不同土地利用方式下土下溶蚀速率及其主要土壤性状，并利用典范分析法分析了影响岩溶速率的主要环境因子。结果不同土地利用方式下溶蚀速率范围为85.14~195.59 mg/(m²·d)，溶蚀速率依次为自然林地>自然草地>人工草地>自然灌丛>人工林地，自然状态下的岩溶作用强于人工干预下的岩溶作用，且从土地利用方式来看林地的岩溶作用优于草地和灌丛。溶蚀速率与土壤容重呈极显著正相关关系(P<0.01，R=0.664)；与土壤孔隙度和土壤含水量呈极显著负相关关系(P<0.01)，相关系数分别为−0.711和−0.521。结论人类活动能够抑制岩溶作用的进程，人工种草效果要好于人工造林。

Modelling of atmospheric CO2 consumption by chemical weathering of rocks: application to the Geronne,Congo and Amazon basins

PurposeTo study the rock dissolution rate and its main influencing factors under different land uses.Method The quantitatively study on rock dissolution rate and its main soil properties under different land uses were conducted based on field sampling, laboratory measurement and geostatistical analysis. The main environmental factors affecting the rock dissolution rate were analyzed by using the canonical analysis method.ResultThe range of dissolution rate under different land use patterns was 85.14-195.59 mg/(m²·d). The rock dissolution rate of different land uses followed the order: natural forest land>natural grassland>artificial grassland>natural shrub land>artificial forest land; the rock dissolution under natural land use patterns was stronger than that under artificial intervention, and the rock dissolution rate of forest land was better than that of grassland in terms of land use patterns. The dissolution rate had a extremely significant positive correlation with soil bulk density (P<0.01), with a correlation coefficient of 0.664; it had a extremely significant negative correlation with soil porosity and soil water content (P<0.01), with a correlation coefficient of −0.711 and −0.521, respectively. Each factor was related to each other and restricted each other, which jointly affected the dissolution intensity.ConclusionHuman activities can promote rock dissolution rate, and the effect of planting grass is better than that of planting forest.