Glacier shape factors(area,length,and thickness),climatic factors(annual temperature and precipitation),mass balance,and other influence factors,of the Qiyi glacier velocity and their intensity were analyzed with the application of the path analysis method during 1958-2007.Results indicate that glacier velocity was mainly influenced by glacier shape,followed by mass balance and climatic conditions.Among the influence factors,glacier area and thickness are most significant,and direct and indirect path coefficients are respectively 6.56,4.71,19.29 and 13.57.This research provides information for further understanding glacier velocity and its influencing factors.
Alpine soil infiltration process is an important part of the hydrological characteristics of alpine soil in permafrost. This research is carried out in the source region of the Yellow River where the permafrost is severely degraded, using various methods for choos- ing typical sample areas, and to experiment, study and simulate the soil water curve, soil saturated hydraulic conductivity, soil in- filtration and soil moisture under different characteristics of degraded vegetation. The results indicate that the empirical equation θ=AS B, proposed by Gradner and Visser, is very reliable in simulating the soil moisture curve; soil saturated hydraulic conductiv- ity and soil infiltration are significantly different under different vegetation coverage: in the soil surface within 0-10 cm, the satu- rated hydraulic conductivity and infiltration intensity of Black Beach are the strongest; respectively, in soil layers below 30 cm, vegetation has almost no impacts on the saturated hydraulic conductivity, infiltration intensity and soil moisture content. Signifi- cant reduction of soil moisture occurs in soil surfaces with degraded vegetation. The more serious the degradation, the more water loss, and it can be up to 38.6% in the worst situation. Soil moisture of developed vegetation root systems in depths within 10-20 cm has the greatest impact on the soil environment, and the loss of moisture induces difficulty in the restoration of degraded meadows. Through a comparative study, the Kostiakov infiltration equation f(t) = at b is more applicable for studies on the process of soil moisture infiltration of the alpine meadow in the source region of the Yellow River.
