Vertical variation of soil moisture in the loess hilly and gully region and its influence factors
QIU Dexun1,2, ZHAO Baili3, YIN Diansheng4, MU Xingmin1,2,3, GAO Peng1,2,3
1. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences, 712100, Yangling, Shaanxi, China; 2. University of Chinese Academy of Sciences, 100049, Beijing, China; 3. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, 712100, Yangling, Shaanxi, China; 4. China Water Huaihe Planning Design and Research Co., Ltd., 230601, Hefei, China
Abstract：[Background] Soil moisture (SM) is one of the key factors for plant growth and eco-environment reconstruction on the Loess Plateau of China. Vertical variation of SM as affected by landform and land use was studied in the Zhifanggou watershed of Ansai county in Shaanxi province.[Methods] We selected 78 representative plots with four land use types in the whole watershed. Three sampling points were selected on the diagonal of each plot. The sampling depth ranged from 0 to 1 000 cm. A total of 40 samples were collected at each point by using a soil auger (10 cm intervals from 0 to 100 cm, 20 cm intervals from 100 cm to 500 cm, and 50 cm intervals from 500 cm to 1 000 cm). The average soil moisture, standard deviation and coefficient of variation of each layer were calculated. The effects of different factors on soil moisture were analyzed quantitatively by variance contribution rates. LSD multiple comparison and t-test were used to compare the differences of soil moisture under different conditions.[Results] 1) The vertical distribution characteristics of SM in 0-1 000 cm were different under different land use. With the increase of soil depth, the SM of the forest land decreased rapidly (0-50 cm) to 6%-9%. The SM of the bush land decreased first (0-50 cm) and then increased slowly. The SM of the abandoned grassland and the farmland increased gradually with the increase of soil depth, and finally stabilized. 2) In general, the longer vegetation age, the lower mean soil moisture. However, in the abandoned grassland, the trend was not obvious. 3) The SM in the shallow layer (0-200 cm):abandoned grassland (10.20%) > farmland (10.04%) > bush land (9.39%) > forest land (8.91%); in the deep layer (200-1 000 cm):farmland (13.50%) > abandoned grassland (13.34%) > bush land (11.66%) > forest land (7.87%). This indicated that the abandoned grassland maintained SM well, while the forest land was relatively poor. 4) The slope had a significant effect on the SM in the shallow layer of the abandoned grassland and the deep layer of the forest land. The steeper a slope was, the lower SM was observed. The aspect had a significant effect on the SM in the shallow layer of the forest land and the abandoned grassland, and the SM on the sunny slope was higher than the shade. On the whole, the SM and the coefficient of variation both decreased first and then increased, which showed a significant positive correlation. Land use, slope and their interaction had significant influence on the SM in shallow layer, the contribution rate of slope was the largest (34.85%), and land use had significant influence on the SM in deep layer, the contribution rate was 23.03%.[Conclusions] The SM in loess hilly and gully area had obvious vertical variation, and was affected jointly by land use, slope and aspect. Abandoned grassland may keep SM better, but forest land was relatively poor. Topography was an important factor affecting the variation of SM in shallow layer, while SM in deep layer was mainly affected by land use.
邱德勋, 赵佰礼, 尹殿胜, 穆兴民, 高鹏. 黄土丘陵沟壑区土壤水分垂直变异及影响因素[J]. 中国水土保持科学, 2021, 19(3): 72-80.
QIU Dexun, ZHAO Baili, YIN Diansheng, MU Xingmin, GAO Peng. Vertical variation of soil moisture in the loess hilly and gully region and its influence factors. SSWC, 2021, 19(3): 72-80.
姚雪玲, 傅伯杰, 吕一河. 黄土丘陵沟壑区坡面尺度土壤水分空间变异及影响因子[J]. 生态学报, 2012, 32(16):4961. YAO Xueling, FU Bojie, LÜ Yihe. Spatial patterns of soil moisture at transect scale in the Loess Plateau of China[J]. Acta Ecologica Sinica, 2012, 32(16):4961.
[2]
胡伟, 邵明安, 王全九. 黄土高原退耕坡地土壤水分空间变异性研究[J]. 水科学进展, 2006, 17(1):74. HU Wei, SHAO Ming'an, WANG Quanjiu. Study on spatial variability of soil moisture on the recultivated slope-land on the Loess Plateau[J]. Advances in Water Science, 2006, 17(1):74.
[3]
裴艳武, 黄来明, 贾小旭, 等. 黄土高原2种典型灌木地土壤水分有效性及其影响因素[J]. 土壤学报, 2019, 56(3):627. PEI Yanwu, HUANG Laiming, JIA Xiaoxu, et al. Soil water availability and its influencing factors in soils under two types of shrubberies typical of the Loess Plateau[J]. Acta Pedologica Sinica, 2019, 56(3):627.
[4]
CHEN Liding, HUANG Zhilin, GONG Jie, et al. The effect of land cover/vegetation on soil water dynamic in the hilly area of the Loess Plateau, China[J]. Catena, 2007, 70(2):200.
[5]
薛志婧, 马露莎, 安韶山, 等. 黄土丘陵区小流域尺度土壤有机碳密度及储量[J]. 生态学报, 2015, 35(9):2917. XUE Zhijing, MA Lusha, AN Shaoshan, et al. Soil organic carbon density and stock at the catchment scale of a hilly region of the Loess Plateau[J]. Acta Ecologica Sinica, 2015, 35(9):2917.
[6]
王力, 邵明安, 侯庆春. 延安试区土壤干层现状分析[J]. 水土保持通报, 2000, 20(3):35. WANG Li, SHAO Ming'an, HOU Qingchun. Status of dried Soil layer in the Yan'an experimental area[J]. Bulletin of Soil and Water Conservation, 2000, 20(3):35.
[7]
刘鑫, 毕华兴, 李笑吟, 等. 晋西黄土区基于地形因子的土壤水分分异规律研究[J]. 土壤学报, 2007, 44(3):411. LIU Xin, BI Huaxing, LI Xiaoyin, et al. Variation of soil moisture in relation to topographic factors in loess region of West Shanxi[J]. Acta Pedologica Sinica, 2007, 44(3):411.
[8]
王云强, 邵明安, 刘志鹏. 黄土高原区域尺度土壤水分空间变异性[J]. 水科学进展, 2012, 23(3):310. WANG Yunqiang, SHAO Ming'an, LIU Zhipeng. Spatial variability of soil moisture at a regional scale in the Loess Plateau[J]. Advances in Water Science, 2012, 23(3):310.
[9]
杨磊, 卫伟, 陈利顶, 等. 黄土丘陵沟壑区深层土壤水分空间变异及其影响因子[J]. 生态与农村环境学报, 2012, 28(4):355. YANG Lei, WEI Wei, CHEN Liding, et al. Spatial variation of deep soil water in the loess hilly and gully regions and its influencing factors[J]. Journal of Ecology and Rural Environment, 2012, 28(4):355.
[10]
YAO Xueling, FU Bojie, LÜ Yihe, et al. The multi-scale spatial variance of soil moisture in the semi-arid Loess Plateau of China[J]. Journal of Soils and Sediments, 2012, 12(5):694.
[11]
张瑞, 曹华, 王云强, 等. 黄土丘陵沟壑区小流域土壤水分空间变异性及其影响因素[J]. 水土保持研究, 2012, 19(5):52. ZHANG Rui, CAO Hua, WANG Yunqiang, et al. Spatial variability of soil moisture and its influence factors in watershed of gully region on the Loess Plateau[J]. Research of Soil and Water Conservation, 2012, 19(5):52.
[12]
YANG Lei, WEI Wei, CHEN Liding, et al. Response of temporal variation of soil moisture to vegetation restoration in semi-arid Loess Plateau, China[J]. Catena, 2014(115):123.
[13]
ZANG Hao, LEI Xiangdong, MA Wu, et al. Spatial heterogeneity of climate change effects on dominant height of larch plantations in northern and northeastern China[J]. Forests, 2016, 7(7):151.
[14]
刘志鹏, 邵明安. 黄土高原小流域土壤水分及全氮的垂直变异[J]. 农业工程学报, 2010, 26(5):71. LIU Zhipeng, SHAO Ming'an. Vertical variations of soil moisture and total nitrogen in small catchment on Loess Plateau[J]. Transactions of the CSAE, 2010, 26(5):71.
[15]
HU Guangyin, DONG Zhibao, LU Junfeng, et al. The developmental trend and influencing factors of aeolian desertification in the Zoige Basin, eastern Qinghai-Tibet Plateau[J]. Aeolian Research, 2015, 19(Part B):275.
[16]
杨维西. 试论我国北方地区人工植被的土壤干化问题[J]. 林业科学, 1996, 32(1):78. YANG Weixi. The preliminary discussion on soil desiccation of artificial vegetation in the northern regions of China[J]. Scientia Silvae Sinicae, 1996, 32(1):78.
[17]
杨文治, 马玉玺, 韩仕峰. 黄土高原地区造林土壤水分生态分区研究[J]. 水土保持学报, 1994, 8(1):1. YANG Wenzhi, MA Yuxi, HAN Shifeng. Soil water ecological regionalization of afforestation in Loess Plateau[J]. Journal of Soil and Water Conservation, 1994, 8(1):1.
[18]
赵忠, 李鹏, 王乃江. 渭北黄土高原主要造林树种根系分布特征的研究[J]. 应用生态学报, 2000, 11(1):37. ZHAO Zhong, LI Peng, WANG Naijiang. Distribution patterns of root systems of main planting tree species in Weibei Loess Plateau[J]. Chinese Journal of Applied Ecology, 2000, 11(1):37.
[19]
安文明, 梁海斌, 王聪, 等. 黄土高原阴/阳坡向林草土壤水分随退耕年限的变化特征[J]. 生态学报, 2017, 37(18):6120. AN Wenming, LIANG Haibin, WANG Cong, et al. Dynamic characteristic of soil water with an increase in restoration years on the shady and sunny slope aspects of the Loess Plateau[J]. Acta Ecologica Sinica, 2017, 37(18):6120.
[20]
王爱娟, 章文波. 林冠截留降雨研究综述[J]. 水土保持研究, 2009, 16(4):55. WANG Aijuan, ZHANG Wenbo. Reviews of vegetation interception of rainfall[J]. Research of Soil and Water Conservation, 2009, 16(4):55.
[21]
程积民, 万惠娥, 王静,等. 黄土丘陵半干旱区天然草地土壤水分调控研究[J]. 草地学报, 2003, 11(4):296. CHENG Jimin, WAN Huie, WANG Jing, et al. Soil water regulation of the natural grassland of semi-arid loess hilly region[J]. Acta Agrestia Sinica, 2003, 11(4):296.
[22]
徐学选, 刘文兆, 高鹏, 等. 黄土丘陵区土壤水分空间分布差异性探讨[J]. 生态环境, 2003, 12(1):52. XU Xuexuan, LIU Wenzhao, GAO Peng, et al. The discussion on soil moisture distributional diversity in hilly Loess Plateau region[J]. Ecology and Environment Sciences, 2003, 12(1):52.
[23]
王瑜, 朱清科, 赵维军, 等. 陕北黄土区人工林地土壤水分的垂直变化规律[J]. 中国水土保持科学, 2015, 13(6):54. WANG Yu, ZHU Qingke, ZHAO Weijun, et al. Vertical distribution of soil moisture in artificial forests in loess region of northern Shaanxi[J]. Science of Soil and Water Conservation, 2015, 13(6):54.
2021, Vol. 19 
