摘要
为揭示黄土丘陵区BSCs(生物土壤结皮)的入渗特征,以甘肃省定西市安家沟小流域为例,选择荒草地、沙棘灌丛和油松林3种典型土地利用类型进行采样,采用环刀模拟法研究不同土地利用类型下苔藓结皮和地衣结皮对水分入渗的影响.结果表明:①不同土地利用类型下的2种BSCs均明显减少初渗速率和达到稳渗所需时间,初渗速率降幅最小值、最大值分别出现在油松林、荒草地下地衣结皮;荒草地、沙棘灌丛苔藓结皮稳渗速率相对裸土分别增加2.4%、10.0%,而二者地衣结皮明显降低稳渗速率,降幅分别为45.2%和55.0%,油松林下苔藓结皮和地衣结皮稳渗速率均增幅为18.2%.②苔藓结皮在3种土地利用类型下均促进土壤水分入渗,其入渗量调控率在荒草地、沙棘灌丛和油松林下分别是1.0%、10.0%和0.7%;而地衣结皮在荒草地和沙棘灌丛下明显阻碍水分入渗,其入渗量调控率的绝对值分别为43.9%和50.0%,在油松林下的入渗量调控率则为16.5%.③Horton模型对生物土壤结皮入渗过程拟合效果最好,较适于描述本区具有生物结皮覆盖的土壤入渗特征.
In order to explore how the biological soil crusts （BSCs） affect soil water infiltration in the Chinese Loess Plateau, a typical loess hilly region in Anjiagou catchment of Gansu Province was selected as the typical study area. The specific infiltration rate and cumulative infiltration volume were measured by cutting-ring method in the field experimental plots which were covered with BSCs under three land-use types （i. e. , natural grassland, sea buckthorn shrubland and Chinese pine forest）. The results showed： （1） The two types of BSCs （i. e. , moss crusts and lichen crusts） under different land uses can lower the initial infiltration rate significantly, and shorten the time to reach the stable infiltration rate. Moss crusts raise the stable infiltration rate with the increasing rates of 2. 4% , 10. 0% and 18.2%. The stable infiltration rate of lichen crusts under natural grassland and seabuckthorn were significantly lower than that of bare soil, with the reduction rates of 45.2% and 55.0%. （2）The effects of BSCs on infiltration volume were not steady either. The moss crust under the three types of land uses with the increasing rate of 1.0% , 10.0% and 0.7% , respectively. However, lichen crusts with the reduction rates of 43.9% and 50. 0% under abandoned and seabuckthorn respectively, and with an increasing rate 16.5% under Chinese pine forest. （3） Soil infiltration simulation indicated that Horton is better than Kostiakov and Philip infiltration models. It means that Horton equation is more suitable to describe the soil covered by BSCs in the loess hilly region of China.
出处
《环境科学研究》
EI
CAS
CSSCI
CSCD
北大核心
2014年第4期415-421,共7页
Research of Environmental Sciences
基金
国家自然科学基金项目(41371123)
国家杰出青年基金项目(40925003)
