CAJ | 학술논문

采用人工降雨实验方法研究了黑河上游天老池小流域对放牧以及禁牧情况下亚高山草甸草地的人工降雨截留过程,并用简易浸泡法测定了草地冠层最大持水能力.结果显示：放牧干扰显著改变了亚高山草甸草地地表植被冠层特征和物种组成,放牧草地与禁牧草地相比下冠层盖度、生物量和冠层株高分别减少了9%,55%,19.2 cm,草地截留特征受不同冠层结构的影响产生一定差异.在一个给定降雨强度下,草地冠层截留量先呈线性增加,穿透雨出现后呈现指数增长,其中禁牧草地出现穿透雨的人工降雨量为1.80 mm,放牧草地的为1.10 mm.草地截留量随降雨强度的增加呈现先增加后减少的变化,在0.7～0.8 mm/min降雨强度级别下截留量最大,草地截留率与降雨强度具有负幂函数关系.研究区草地冠层截留量较大,使用人工降雨法在降雨强度级别为0.7～0.8 mm/min下实测得到草地最大截留容量,禁牧草地的为6.50 mm,放牧草地的为5.17 mm.在降雨强度为<0.3 mm/min时(研究区主要降雨强度),实测禁牧草地饱和截留量为1.95 mm,放牧草地的为1.29 mm.使用简易浸泡法测得禁牧草地截留容量为0.92 mm,放牧草地的为0.65 mm.
채용인공강우실험방법연구료흑하상유천로지소류역대방목이급금목정황하아고산초전초지적인공강우절류과정,병용간역침포법측정료초지관층최대지수능력.결과현시：방목간우현저개변료아고산초전초지지표식피관층특정화물충조성,방목초지여금목초지상비하관층개도、생물량화관층주고분별감소료9%,55%,19.2 cm,초지절류특정수불동관층결구적영향산생일정차이.재일개급정강우강도하,초지관층절류량선정선성증가,천투우출현후정현지수증장,기중금목초지출현천투우적인공강우량위1.80 mm,방목초지적위1.10 mm.초지절류량수강우강도적증가정현선증가후감소적변화,재0.7～0.8 mm/min강우강도급별하절류량최대,초지절류솔여강우강도구유부멱함수관계.연구구초지관층절류량교대,사용인공강우법재강우강도급별위0.7～0.8 mm/min하실측득도초지최대절류용량,금목초지적위6.50 mm,방목초지적위5.17 mm.재강우강도위<0.3 mm/min시(연구구주요강우강도),실측금목초지포화절류량위1.95 mm,방목초지적위1.29 mm.사용간역침포법측득금목초지절류용량위0.92 mm,방목초지적위0.65 mm.
The interception data from two categories of grazing scenario meadows (the grazing meadows and the grazing prohibition meadows) were collected under the artificial raining experiment with a different rainfall intensity and using a simple absorbent method to estimate the water storage capacity of these alpine meadows in Tianlaochi catchment in the upper reach of Heihe River. The results showed that disturbance of grazing had significantly changed the canopy characteristics and the species of subalpine meadow vegetation. Compared with the grazing-prohibition meadow, the canopy coverage, biomass and plant height of the grazing meadows decreased by 9%, 55% and 19.2 cm respectively. Influence by different canopy structures and characteristics, the interception characteristics of the different grazing scenario meadows showed certain differences. With a steadfast rainfall intensity, the interception processes of the alpine meadows were linearly increasing at first and, after the appearance of through fall (when the rainfall reached a value of 1.80 mm for the grazing prohibition and 1.10 mm for the grazing meadows), the interception presented an exponential increase. The relationship between the canopy interception ratio and interception rainfall in alpine meadows can be represented by a power function. The canopy interception of the alpine meadow in our study area could reach a high value. At the 0.7～0.8 mm/min rainfall intensity, the maximum rates of canopy interceptions (canopy storage capacity) for the grazing prohibition and grazing meadows were 6.50 mm and 5.17 mm. At the 0.3 mm/min rainfall intensity, which was similar to the realistic rainfall condition, the canopy interceptions for the grazing prohibition and grazing meadows were 1.95 mm and 1.29 mm. The canopy storage capacity measured by the simple storage absorbent method for the grazing prohibition and grazing meadows were 0.92 mm and 0.65 mm.