江汉平原耕地土壤氮素空间尺度套合与变异规律研究.docVIP

江汉平原耕地土壤氮素空间尺度套合与变异规律研究 于 婧1，周 勇12，聂 艳2，刘 凡1 （1华中农业大学资源与环境学院，武汉430070；2华中师范大学城市与环境科学学院，武汉 430079） 【目的】为克服尺度效应对氮素空间变异规律认识的影响，更加充分的利用多尺度空间信息【方法】【结果】【结论】Spatial Variability of Soil Nitrogen in Different Scales and Nested Simulation YU Jing1，ZHOU Yong1,2, NIE Yan2, LIU Fan1 ( 1College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070；2College of Urban Environment Sciences, Centre China Normal University, Wuhan 430079 ) Abstract:【Objective】The purpose of this paper is to mini the influence of the scale effect on understanding nitrogen spatial variation, and to use multi- scale spatial information adequately. 【Method】ested scenario’s were tested in a Houhu farm in the Jianghan Plain; the variation of soil total nitrogen (TN) was simulated by using geostatistics in scale of 400, 100 and 50 meters separately; effect of scale on TN variation was analyzed; the simulating method under multi-scale data was put forward; and the spatial distribution of TN was described in this region. 【Result】 Data in three scales all agreed with normal distribution; spherical models fit best for semi-variogram; in different scale, TN varied under different driving factors, which led to the appearance of the scale effect. The estimation, through multi-scale simulation, was more accurate than the traditional method, which wasn’t limited by nested distance(100 m, 50 m in this research). Furthermore, the standard error was only 1/2 of the original method in local area; the degree that the precision improved relates to of scale distance.【Conclusion】The simulation of soil nutrition by nested kriging method, is more reliable and concrete, which can offer a scientific basis for formulation and implementation of the precision agricultural scheme in Jianghan Plain in China. Key words: Spatial variation; Scale effect; Nested simulating method 0 引言 【研究意义】土壤养分元素的空间分布是精准施肥、土壤演变等农业精准研究的基础[1～3]，而土壤养分空间变异的尺度效应正逐渐引起土壤学家们的关注。土壤学家发现，在研究同一养分属性的空间结构时，由于采用的空间尺度的大小不一，其变异特征往往相差很大[4]，给研