%0 Journal Article %T 土壤侵蚀对坡耕地土壤水分及入渗特性影响 %T Effects of Soil Erosion on Soil Moisture and Infiltration Characteristics of Slope Farmland %A 娄义宝 %A 史东梅 %A 江 娜 %A 金慧芳 %A 叶 青 %A LOU,Yibao %A SHI,Dongmei %A JIANG,Na %A JIN,Huifang %A YE,Qing %J 土壤学报 %J ACTA PEDOLOGICA SINICA %@ 0564-3929 %V 57 %N 6 %D 2020 %P 1399-1410 %K 坡耕地;土壤侵蚀;入渗;水分特征曲线;抗旱性能 %K Sloping cultivated land; Soil erosion; Infiltration; Water characteristic curve; Drought resistance %X 土壤水分对雨养农业坡耕地具有重要的意义,利用铲土侵蚀模拟试验小区,对不同侵蚀程度坡耕地的土壤水分特征曲线、土壤入渗、土壤水库特征及抗旱性能进行了研究。结果表明:(1)土壤侵蚀程度加剧可以使相同吸力下土壤的容积含水量降低,不利于坡耕地土壤的水分贮存,使坡耕地土壤抗旱性能降低。紫色土坡耕地土壤入渗速率随着土壤侵蚀程度加剧,0~10 cm层土壤入渗速率逐渐降低,同时随着土壤侵蚀程度加剧,不同垂直深度上各个土层土壤入渗速率差异逐渐减小。(2)不同侵蚀程度坡耕地土壤水库特征差异显著,紫色土坡耕地土壤总库容随着土壤侵蚀程度加剧先呈现上升趋势,土壤总库容的大小表现为S-10(422.7 t•hm-2)>S-5(413.1 t•hm-2)>S-15(408.2 t•hm-2)>S-0(404.9 t•hm-2)>S-20(403.5 t•hm-2)。随着侵蚀程度加剧紫色土坡耕地土壤水库无效水分有着不同程度的增加,土壤侵蚀可以减小水库持水效率,但侵蚀程度对水库持水效率影响不大。(3)不同侵蚀坡耕地0~40 cm层土壤的各贮水特征之间差异不大,同一土层深度不同侵蚀程度坡耕地最大吸持贮水量占饱和贮水量的75%左右。随侵蚀程度加剧坡耕地土壤抗旱性变差,相同吸力下,不同侵蚀程度坡耕地耕层土壤累计损失水百分率随侵蚀程度加剧呈现不同程度的增加。研究结果可为地块尺度上紫色土坡耕地土壤水分和抗旱性能调控提供技术参数。 %X 【Objective】Cultivated slopeland in the hilly areas of purple soil is an important erosion inflicted area in the Yangtze River Basin, where soil moisture is not only the main factor governing agricultural productivity of the land and crop growth in the area, but also an important one influencing the erosion process therein. Soil moisture is of great significance to rain-fed agricultural sloping farmlands. This study was to explore impacts of soil erosion on soil moisture and water infiltration in sloping farmlands, in an attempt to provide some parameters as a basis for control of soil water erosion in sloping farmlands in hilly purple soil areas.【Method】For this paper, a soil erosion simulation experiment was carried out on a shoveled plot of land, to explore soil water characteristic curves, water infiltration, soil water pool characteristics and drought resistance of the sloping farmland 0, 5, 10, 15 and 20 cm in depth.【Result】Results show: (1) Aggravation of soil erosion degree reduced volumetric water content of the soil that remained the same in suction, which is detrimental to water storage in the sloping farmland soil, leading to reduced drought resistance of the slopeland. Under the same suction force, soil volumetric moisture content decreased with aggravating soil erosion; when soil erosion occurred in the 0 to 20 cm soil layer, soil volumetric water content decreased by 7.8% ~ 24.32%, or 17.80% on average. With aggravating soil erosion, soil water infiltration rate gradually decreased too in the 0~10 cm soil layer, and at the same time soil water infiltration rate tended to be similar in all soil layers regardless of vertical depth. (2) Soil water pool characteristics varied sharply with the degree of soil erosion. With aggravating soil erosion, the total soil water pool capacity tended to rise firstly, and exhibited an order of S-10 (422.7 t•hm-2 ) > S-5 (413.1 t•hm-2) > S-15 (408.2 t•hm-2) > S-0 (404.9 t•hm-2) > S-20 (403.5 t•hm-2) by layer, and at the same time, ineffective portion of the water pool increased to a varying extent; soil erosion reduced water holding efficiency of the soil, which, however, almost had nothing to do with degree of the erosion. (3) Soil water pool characteristics in the 0~40 cm soil layer did not vary much from slopeland to slopeland different in soil erosion; the maximum water holding capacity accounts for 75% of the saturated water holding capacity in the soil layer the same in depth, regardless of erosion degree. With aggravating soil erosion cumulative water loss from the cultivated layer, under the same suction, increased by a varying degree, and displayed a rising trend on the whole, and a declining order, by layer, of S-10> S-20 > S-15 > S-5 > S-0; This shows that under the same soil suction, the surface soil layer lost the least water and the 0~10 soil layer the most.【Conclusion】Soil erosion causes destruction of soil structure, thus reducing soil water infiltration, water retaining capacity, and drought resistance of sloping farmlands. All the findings in this research may serve as technical parameters for the regulation of soil moisture and drought resistance of farmlands on purple soil slopes on the plot scale. %R 10.11766/trxb201912270288 %U http://pedologica.issas.ac.cn/trxb/home %1 JIS Version 3.0.0