THE SPATIAL STATISTICS STUDY OF AGRINOMIC PARAMETERS AND SOIL MOISTURE CONTENT OF WHEAT JOINTING STAGE

摘要

Wheat domenstration base is selected as the sampling area in this paper in Lingxian country of Shandong province, commodity grain bases of China. The objective of this study was to evaluate the efficiency of spatial statistical analysis about soil moisture content and agronomic parameters of wheat jointing stage. Field monitoring combined with laboratory analysis, based on the GPS localization data, soil moisture content and wheat agronomic parameters about 21 sampling points was collected. Soil moisture content was determined by the Time Domain Reflectometry (TDR), the wheat chlorophyll content was obtained by Minoha chlorophyll meter(SPAD--502), wheat dry matter production was measured. Geostatistical analysis, combined with geographical information system(GIS), Semivariogram model was established, spherical model is the semivariogram model of soil moisture content, gaussian model is the superior semivariogram model of wheat chlorophyll content and dry matter production. The range, nugget and sill of soil moisture content and wheat agronomic parameters were calculated, the ratio of nugget and sill of soil moisture content, wheat chlorophyll content and wheat dry matter production was 97.3%,81.3% and 50%, respectively. there was the weak spatial autocorrelation of soil moisture content, the ratio of structural variation is 97.3%, which mainly resulted from the factors, precipitation, temperature and wind speed, et al. There was the medium spatial autocorrelation of wheat chlorophyll content and wheat dry matter production, the ratio of structural variation is 81.3% and 50%, which mainly resulted from the factors, human activities, cultivation measure and management measures, et al. The spatial correlation distances of soil moisture content, wheat chlorophyll content and wheat dry matter production were 34.69 km, 76.279 km and 14.202 km, respectively. Block Kriging was applied, and the spatial distributing map and map of standard deviation of Kriging estimates of soil moisture content and agronomic parameters was drawn. From the distribution types, it has obvious slabby and plaques characteristics for Kriging estimates map of soil moisture content and wheat chlorophyll content, and it has ribbon characteristics for wheat dry matter production. Standard deviation map of Kriging estimated presented granular mode as the mentioned three indices. The farther from the sampling, the more uncertainty of Kriging interpolation map, which proved to be important for smoothing data with this method and explained the unbias of Kriging. In a word, the spatial statistics of soil moisture content, dry matter production and the chlorophyll content benefited for fertilizer and water control, reasonable canopy architecture of wheat establishment, also provided the foundation for the high yield and quality of wheat.