坝地土壤养分的空间变异性研究  

Spatial Variability of Soil Nutrients of a Dam Land

作　　者：陈卫国[1] 吕春娟[2] 刘秀珍[2] 毕如田[2] 

机构地区：[1]山西农业大学生命科学学院,山西太谷030801 [2]山西农业大学资源环境学院,山西太谷030801

出　　处：《土壤通报》2015年第4期829-836,共8页Chinese Journal of Soil Science

基　　金：国家青年科学基金项目(41401619);山西省自然科学基金(2014011034-1);山西省科技推广项目(2012)资助

摘　　要：坝地是我国粮食安全、耕地动态平衡的有力保障。研究借助GPS定位技术,以网格采样法测定了黄土高原典型骨干坝坝地0~20 cm和20~40 cm土壤养分,采用传统的统计学和地统计学GS+相结合的方法分析了其空间变异特征,为坝地的精准管理、合理施肥提供科学依据。结果表明,坝地土壤养分严重缺乏且分布不均衡,坝地0~20 cm土壤除速效钾属于"一般"水平之外,有机质、全氮、碱解氮、速效磷养分含量都属于"稍低"或"低"水平,20~40 cm土层的各养分质量分数普遍比0~20 cm的还低。不同土层土壤养分的水平空间半变异函数不同,空间相关性的变程范围为64~245 m,坝地0~20 cm土层中有机质基底效应为32.60%,属于中等空间依赖性;0~20 cm土层中碱解氮、20~40 cm土层中有机质和速效磷的基底效应均为100%,具有弱空间相关性;其余土壤养分的基底效应均小于25%,具有强空间依赖性,说明坝地土壤受区域性因素影响较大。但坝地淤积物的原始水平空间的渐变分布规律由于多年种植已被人为随机因素扰动,土壤养分呈现非规则的水平空间分布格局,与原位土壤养分分布格局不同。Dam land is a strong guarantee of food security in terms of the cultivated land dynamic equilibrium for China. To provide a scientific basis for precise fertilization and management of dam land soil, the spatial structures of soil nutrients(0- 20 cm and 20- 40 cm)of the dam land were analyzed by geostatistics method(GS+9.0) and classical statistics method. Results showed that soil nutrients of the dam land were very low and in an uneven distribution. At the soil depth of 0- 20 cm, except the content of rapidly-available potassium(AK) belonging to 'general' level, the contents of organic matter(OM), total nitrogen(TN), alkali-hydrolysable nitrogen(AN)and available phosphorus(AP)were all in low levels,but the contents of soil nutrients at the soil layer of 20- 40 cm were even lower than those at 0- 20 cm. Hence, semi-variance models of soil nutrients of different soil layers were different and the range of spatial correlation was from 64 m to 245 m. The Co /(Co+C)of organic matter at depth 0-20 cm was 32.60% with moderate spatial dependence; alkali-hydrolysable nitrogen(AN)at depth 0- 20 cm, organic matter and available phosphorus(AP)at depth 20- 40 cm, were all 100% with weak spatial dependence. However,the Co /(Co+C)of other soil nutrients was less than 25%, which demonstrated strong spatial dependence as greatly influenced by regional factors. Due to years of planting, the original horizontal space distribution of the dam land sediments had been disturbed by random factors and the irregular horizontal spatial patterns of soil nutrients were formed.

关 键 词：黄土高原 坝地 土壤养分 空间分布 地统计 

分 类 号：S158[农业科学—土壤学]