青海高寒丘陵区土壤有效水的时间稳定性  

Time stability of soil effective moisture in alpine hilly region of Qinghai

作　　者：张鹏[1] 王冬梅[1] 丁聪 李平 ZHANG Peng;WANG Dongmei;DING Cong;LI Ping(School of Soil and Water Conservation,Beijing Forestry University,100083,Beijing,China)

机构地区：[1]北京林业大学水土保持学院

出　　处：《中国水土保持科学》2019年第5期9-17,共9页Science of Soil and Water Conservation

基　　金：国家重点研发计划“基于调水净水功能提升的小流域尺度景观格局优化调配”(2017YFC0504604-04)

摘　　要：为了探究高寒丘陵区土壤有效水的时空变异特征,基于青海高寒丘陵区暗门滩小流域2018年5-8月土壤有效水数据,通过经典统计和时间稳定性分析,研究该区域土壤有效水的空间变异和时间稳定性特征。结果表明:1)研究区各土层旱季耗水,雨季补水;表层(0~20 cm)土壤有效水表现为强变异性,深层(>20~100 cm)土层有效水均表现为中等变异性;2)Spearman秩相关系基本均高于0.75,且呈现出极显著相关,研究区小流域>20~100 cm土壤的有效水在整个观测期间都有较高的时间稳定性;3)>20~100 cm有效水平均相对偏差的变化范围(-79.84%~129.86%),及其标准差(12.63%~55.62%),随土层厚度的增加,土壤有效水平均相对偏差及其标准差的波动范围都逐渐减小,样点土壤有效水时间稳定性随土层厚度增加而增强;4)通过相对差分分析选出各土层代表点,决定系数(0.6682~0.8117),精度要求不高时,可用于小流域各层土壤有效水估算,并对流域植被配置优化以及水资源的高效管理提供指导。[Background] In the semi-arid areas of Northwest China, soil moisture is one of the key factors limiting vegetation growth and ecological restoration. In the study area, the study of alpine inferiority and single species, soil temporal and spatial variability of soil water is beneficial to soil water management and vegetation reconstruction. [Methods] From May 15th, 2018 to August 15th, 2018, the soil moisture content of 55 water points in the small watershed of the Anmentan was measured with a CNC 503B neutron meter, measured every 15 days for a total of 7 times;for four soils the type of soil was sampled with a ring cutter, and the soil moisture characteristic curve was measured by an indoor experimental high-speed centrifuge. Then, the soil water content corresponding to the water potential of -1 500 kPa was obtained on the soil water characteristic curve, which is the soil wilting coefficient. The data analysis was done by classical statistical method and time stability analysis, and the data processing tool adopted SPSS and Excel 2016. [Results] 1) The soil in the study area consumes water during the dry season and replenishes water during the rainy season;the 0-20 cm soil layer shows strong variability, and the effective moisture in 20-100 cm soil layer shows moderate variability. 2) The Spearman rank correlation is basically higher than 0.75, and it shows a very significant correlation. The effective moisture of 20-100 cm soil in the small watershed of the study area has high time stability throughout the observation period. The number of points of probability is more than that of shallow layers, and the change of cumulative probability position is small. 3) The range of variation of effective horizontal deviation of 20-100 cm is -79.84%-129.86%, and its standard deviation is 12.63%-55.62%. The relative deviation of soil effective moisture level and the fluctuation range of standard deviation are gradually reduced, and the effective moisture time stability of sample soil increases with the increase of soil

关 键 词：高寒丘陵 有效水 时间稳定性 代表点 黄土高原 

分 类 号：S157[农业科学—土壤学]