祁连山西水林区土壤水分物理性质特征分析

ANALYSIS ON PHYSICAL PROPERTIES OF SOIL MOISTURE CONTENT IN XISHUI FOREST ZONE OF QILIAN MOUNTAIN

在祁连山西水林区内,以青海云杉林、祁连圆柏林、灌丛林和草地为研究对象,对其土壤物理性质和土壤水分特征进行研究,结果表明：①土壤容重均值,青海云杉林〈高山灌丛林〈祁连圆柏林〈低山灌丛林〈草地〈无林地,不同林地土壤容重变动在0.56g/cm^3～0.92g/cm^3,都小于无林地土壤容重1.20g/cm^3;孔隙度有林地明显大于无林地,总孔隙度均值表现为青海云杉林〉高山灌丛林〉祁连圆柏林〉低山灌丛林〉草地〉无林地,不同林地总孔隙度变动在49.08%～71.58%之间。②有林地土壤入渗速率明显高于无林地,土壤渗透系数从大到小的顺序为青海云杉林〉高山灌丛林〉低山灌丛林〉祁连圆柏林〉草地〉无林地。土壤渗透系数（K10）分别比无林地提高了38.85倍、33.07倍、7.29倍、4.79倍、1.85倍。③在旱季和雨季,随着土壤深度的增加,大部分林地土壤含水量呈现递减趋势,其变动幅度小于无林地。④随着土壤深度的增加,各林地土壤饱和持水量逐渐减小;青海云杉林表层土壤蓄水功能最好,其它林分各层次差异较小。

In this paper, the physical properties and moisture content of soil in Qinghai dragon spruce forest, Qilian round cypress forest, scrub forest and grasslands inside the Xishui Forest Zone of Qilian Mountain were studies. The results showed：①The average bulk density of soil is Qinghai dragon spruce forest 〈 alpine scrub forest 〈 Qilian round cypress forest 〈 grasslands 〈 non-stocked land, and the fluctuation of bulk density of soil is between 0.56g/cm3 and 0.92g/cm3 in different forest region, all are less than that of nonstocked land, which is 1.20 g/cm3. If comparing by soil porosity in the forest land, it is obviously higher than that in non-stocked land, the order of average total soil porosity is Qinghai dragon spruce forest 〈 alpine scrh forest 〈 Qilian round cypress forest 〈 olw mountain scrub forest 〈 grasslands 〈 non - stocked land, and the value fluctuation is between 49.08% and 71.58%. ②The soil permeability rate in forest region is significantly higher than that in non-stocked land. The order of soil permeability coefficient （ K10 ） is Qinghai dragon spruce forest 〈 alpine scrub forest 〈 low mountain scrub forest 〈 Qilian round cypress forest 〈 grasslands 〈 non-stocked land, and the increase reached 38.85 - ,33.07 - ,7.29 - ,4.79 - , and 1.85 - fold respectively compared with non-stocked land. ③ In dry and rainy season, the soil moisture content in most of the forest region decrease progressively with the increase in soil depth, but the fluctuation extent is less than that of non-stocked land. ④The soil saturated moisture capacity in different forest region decrease gradually with the increase in soil depth; the surface layer soil of Qinghai dragon spruce forest has the best water retaining ability, and it does not show obvious difference among others.