| 引用本文: | 刘燕楠,孙贯芳,毛威,等.基于地统计分析的河套灌区土壤水盐空间变异规律分析[J].灌溉排水学报,0,():-. |
| LIU Yan-nan,SUN Guan-fang,Mao Wei,et al.基于地统计分析的河套灌区土壤水盐空间变异规律分析[J].灌溉排水学报,0,():-. |
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| 摘要: |
| 【目的】研究干旱盐渍化灌区不同深度土壤水分和盐分的空间变异规律。【方法】以内蒙古河套灌区隆胜井渠结合区为研究区，通过野外取样和实验室分析结合，应用经典统计学和地统计学方法研究了根系层（0-60 cm）及深层土壤（60-120 cm，120-180 cm）土壤水分和盐分的空间变异性、空间格局及二者之间的关系，并探究了地下水埋深和地下水矿化度对土壤盐分的影响。【结果】①土壤含水率在垂向上大小关系为0-60 cm<60-120 cm<120-180 cm，土壤含盐量为0-60 cm>60-120 cm>120-180 cm。土壤水分和盐分的变异系数和块金系数自上而下逐层减小，变程逐层增大。根系层的土壤水分和盐分均具有中等程度的空间相关性，深层土壤水分和盐分的空间相关性较强。②各层土壤水分的变异系数和块金系数小于土壤盐分，变程大于土壤盐分，二者之间的空间格局存在显著的正相关关系。③研究区各层土壤盐分均与地下水埋深呈指数相关关系，与地下水矿化度呈幂函数关系。当地下水埋深大于2.5m时，总体土壤盐分含量较低，且各层盐分含量变化较小。【结论】研究区土壤盐分呈表聚型，其空间特征和分布格局与土壤水分有着密切的关系。调控地下水埋深是灌区控制土壤盐渍化的关键措施，为有效控制土壤盐渍化，建议地下水埋深控制在2.5m以下。 |
| 关键词: 河套灌区；土壤水盐；地统计学；空间变异；地下水环境 |
| DOI：10.13522/j.cnki.ggps.2021621 |
| 分类号:P641.2；S27 |
| 基金项目:国家自然科学基金项目（面上项目，重点项目，重大项目） |
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| Spatial Variability of Soil Water and Salt in Hetao Irrigation District Based on Geostatistical Analysis |
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LIU Yan-nan1, SUN Guan-fang2, Mao Wei1, CHENG Xiao-yao3, ZHU Yan1, YANG Jin-zhong1
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1.The State Key Laboratory of Water Resource and Hydropower Engineering Science, Wuhan University;2.Institute of Soil and Water Conservation, Northwest Agriculture and Forestry University;3.Zhongnan Municipal Administration General Design Institute Co. Ltd., China Municipal Engineering
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| Abstract: |
| 【Background】The decline of agricultural production caused by soil salinization is one of the major threats worldwide, especially in arid and semi-arid regions. Soil water and salt has significant spatial variability, which increases the difficulty in soil salinity prediction and control. Therefore, understanding spatial variability in soil water and salt is essential to improve water use efficiency and prevent soil salinization.【Objective】This paper aims to analyze the spatial characteristics and variability of soil water and salt at different depths and their relationship in the Hetao Irrigation District. Besides, the influence of groundwater depth and salinity on soil salinity has also been presented.【Method】The Longsheng irrigation area, which is a typical well-canal conjunctive irrigation area, was chosen as the study site. An analysis of soil water content and soil salt content was performed using field sampling combined with laboratory testing.. Then the spatial variability of soil water and salt in root layer (0-60 cm) and deep soil (60-120 cm, 120-180 cm) was analyzed by classical statistical and geostatistical methods. In addition, the relationship between groundwater environment and soil salinity was also analyzed by Pearson correlation analysis. 【Result】① Averaged soil water content at different depths were ranked in the order of 0-60 cm<60-120 cm<120-180 cm, while the averaged soil salt content were ranked in the order of 0-60 cm>60-120 cm>120-180 cm. The variation coefficient and nugget coefficient of soil water and salt decreased monotonically with increasing depth, while the spatial autocorrelation distance increase monotonically layers by layer with increasing depth. Soil water and salt in the root layer both exhibited moderate spatial autocorrelation. In contrast, soil water and salt in deeper soils showed strong spatial autocorrelation. ② On the one hand, the variation coefficient and nugget coefficient of soil water in each layer are smaller than soil salt, while the variation range is larger than soil salt. On the other hand, there was a strong correlation of negative correlation between them. ③ The soil salt in each layer is exponentially related to groundwater depth and is power function of groundwater salinity. When the groundwater depth is greater than 2.5m, the soil salt content is low and the change trend of soil salinity with the groundwater depth is smaller in each layer. 【Conclusion】Salt accumulated in the root zone, and its spatial characteristics and distribution pattern are closely related to soil water. Groundwater depth is the major controlling factor for soil salinity control, and it is recommended that the groundwater depth should be controlled below 2.5m. |
| Key words: Hetao Irrigation District; soil water and salt; geostatistics; spatial variation; groundwater environment |
