Spatial Variation Of Soil Water And Fertilizer And Its Effects On Crop Yield

The North China Plain is major grain-producing region and the main crops are wheat and corn.However,long-term investment in large amounts of water and fertilizer resources resulted in damage to the ecological environment and low utilization of water and fertilizer,the development of a reasonable farmland irrigation fertilization system would be one of the methods to improve water and fertilizer use efficiency.Because of the highly variable nature of soil properties,it is of crucial importance to research the spatial variability of soil moisture and nutrients,the impact on yield,and the optimal deployment of soil moisture monitoring.This study mainly focused on wheat and corn as the research object to determine soil particle size content,bulk density,moisture,nutrients,and crop yield.Using the classical statistics and geo-statistics,we analysis spatial variability of various soil indicators.The main results are as follows:(1)The available maximum water content of soil was normal distribution at 0～40cm and 0～80cm depth,and their coefficients of variation were 14.96%and 13.56%,respectively which showed a medium scale variation.Under the circumstances of 90%confidence interval and Sampling error of 10%.The reasonable sampling number are six at 0～40cm depth and five at 0～80cm depth in the method of classical statistics and determined the specific layout of the location through the geo～statistical.Compared with the measured soil water content of 129 samples,the error is less than 10%.Therefore,based on the available maximum water content of soil moisture monitoring optimization layout method can dramatically reduce the sampling number in the case of regional measurement accuracy assurance.(2)The content of soil clay,silt,and sand in the test area showed a medium scale variation,and the soil bulk density showed weak variation.The spatial distribution of clay particles and powders were basically the same.With the increase of depth,the content of clay particles and powders gradually decreased,while the sand content gradually increased with the depth,and the distribution of soil bulk density was basically the same.The soil water content and ammonia nitrogen content showed moderate variation,and the soil nitrate and nitrogen content had a high variability of different crops.(3)The soil moisture content,soil ammonia nitrogen,and soil nitrate content could explain separately more than 80%changes of crop yield under the single factor conditions without other factors.The relative yield will increase as the value of the variable fertilizer standardization increases stabilized.and plot spatial distribution of yield ratios.In the absence of lack of water and fertilizer,soil texture and bulk density play a crucial role in crop yields.In relatively deficient areas,the factors affecting production are not yet clear,and further exploration is needed.