摘要
了解耕层土壤养分空间变异规律及其与地形因子的相关关系,以期为土壤养分有效利用和农业管理提供理论依据。以延河流域为研究对象,利用地统计学与GIS相关方法,研究土壤空间分布及变异规律,并基于DEM数据提取相关地形因子,分析流域尺度下地形因子对土壤养分空间分布的影响。研究区耕层全氮和有机质处于较低水平,速效钾和有效磷处于中等水平,pH呈弱碱性,空间变异大小依次为速效钾>有效磷>全氮>有机质>pH。构建的土壤养分指标半方差函数决定系数均大于0.6;土壤pH空间分布最为破碎;土壤速效钾和pH块金系数小于25%,主要为结构性因素影响;土壤全氮、有效磷、有机质具有中等水平的块金效应,受结构性因素和随机因素共同作用;其中有效磷块金系数最大,人类活动对其空间变异影响更大。全氮与有机质分布规律由西北向东南先递增后递减,速效钾呈现由西北向东南波浪形递减的分布格局,有效磷整体分布趋势表现为由中游向上下游降低,土壤pH沿某一方向变化的趋势不强。土壤养分空间变异情况与地形因子的相关关系相一致。在地势较低且平坦的区域内,更有利于农业生产,土壤养分较为充足;在高海拔、地形起伏较大区域养分含量相对较低。
To provide a basis for the effective utilization of soil nutrients and agricultural management,the spatial variation rule of topsoil nutrients and its correlation with topographic factors were studied.The authors took Yanhe River Basin as the research object,the spatial distribution and variation of soil nutrients were studied by geostatistics and GIS.Based on DEM data,relevant topographic factors were extracted to analyze the influence of topographic factors on soil nutrient spatial distribution in watershed scale.The results show that the total nitrogen and organic matter in the topsoil of the study area are at a low level,the available potassium and available phosphorus are at medium level,and the p H is weakly alkaline.The spatial variation is in the following order:available potassium>available phosphorus>total nitrogen>organic matter>pH.The determination coefficients of the semi-variance function on soil nutrients are all more than 0.6,the spatial distribution of soil pH is the most fragmented,which are mainly influenced by structural factors.The nugget coefficient of soil available potassium and pH is less than 25%.With the influence of structural and random factors,soil total nitrogen,available phosphorus and organic matter have medium level of nugget effect.And the nugget coefficient of available phosphorus is the highest,indicating that human activities have greater influence on its spatial variation.The distribution of total nitrogen and organic matter increases first and then decreases from northwest to southeast.The distribution pattern of available potassium shows a wave of decreasing from northwest to southeast.The overall distribution trend of available phosphorus is reduced from middle to the upstream and downstream.The trend of pH change along a certain direction is not obvious.The correlation between soil nutrient spatial variation and topographic factors is consistent.In the region of low and flat terrain,the soil nutrients are more abundant,which is conducive to agricultural production.And the nutrient content is relatively low in the areas with large topographic relief at high altitude.
作者
罗丹
毛忠安
张庭瑜
常庆瑞
LUO Dan;MAO Zhongan;ZHANG Tingyu;CHANG Qingrui(Land Surveying,Planning and Design Institute of Shaanxi Provincial Land Engineering Construction Group Co.,Ltd.,Xi'an 710075;Shaanxi Province Land Engineering Construction Group Co.,Ltd.,Xi'an 710075;Shaanxi Provincial Land Engineering Construction Group Co.,Ltd.,Xi'an 710075;Key Laboratory of Degraded and Unused Land Consolidation Engineering,the Ministry of Natural Resources,Xi'an 710075;Shaanxi Provincial Land Consolidation Engineering Technology Research Center,Xi'an 710075;College of Nature Resources and Environment,Northwest A&F University,Yangling,Shaanxi 712100)
出处
《中国农学通报》
2022年第12期79-87,共9页
Chinese Agricultural Science Bulletin
基金
中央高校基本科研业务费资助项目“基于深度学习的灾损土地语义空间分布规律研究及分析”(300102351502)
陕西省耕地地力调查与质量评价项目
陕西省土地工程建设集团科研项目“基于DEM的陕北高原地貌形态空间格局研究”(DJNY2019-8)
陕西省土地工程建设集团有限责任公司科研项目“基于深度学习网络融合多源遥感数据的废弃地块识别研究”(DJNY2021-10)。
关键词
地统计学
耕层土壤养分
空间变异
地形因子
延河流域
geostatistics
topsoil nutrients
spatial variation
topographic factors
Yanhe River Basin
