Study Of Saline Soil Nutrient Spatial Variability In Jiangsu Coastal Area

Soil is a continuous spatial-temporal heterogeneity, with high spatial variability. The study of saline soil nutrient spatial variability of Jiangsu coastal area is helpful to analyze the saline soil environment. And it also could provide an important reference to the improvements and usage of saline soil.This paper selected three temporary images, adopted visual interpretation to extract their respective coastline after data preprocessing, and calculated their length. With the combination of terrestrial boundary and coastline, the saline soil areas were computed, and their changes were analyzed. The soil sampling database was composed by the union of soil spatial and nutrient data. The spatial variability of saline soil organic matter, soil available phosphorus, soil available potassium, soil pH value and soil conductivity in Jiangsu coastal area was analyzed by the geostatistical method, and its soil environment was realized. The research results were obtained as follows:1. The length of coastline was 532.553 km in 1987, 521.534 km in 2003, 525.483 km in 2007.2. The area of saline soil was 500848.18 hm~2 in 1987, 553221.99 hm~2 in 2003, 576452.10 hm~2 in 2007.3. The spatial variability of saline soil organic matter, soil available phosphorus, soil available potassium, and soil conductivity in Jiangsu coastal area was medium, and the spatial variability of saline soil pH value was weak.4. The trend of soil nutrient spatial variability in up and down stratum was close, and the content of soil organic matter, soil available potassium and soil available phosphorus of up stratum moved towards consistently with the coastline: the farther from the coastline, the higher the soil organic matter content was, the lower both the soil available phosphorus and potassium content were.5. The saline soil nutrient of the northern eroded type was close to the southern stabilized type in the offshore region, and the differences between the middle alluvial type and them were obvious:①the organic matter content of the south and north were higher than the middle part,②the soil available phosphorus content of the middle was the highest, the south was next, and the north was the lowest,③the soil available potassium content of the middle was higher, and the south and north was lower,④the soil pH value of both the south and north was a little higher than the middle,⑤the soil conductivity of the middle and north was higher than the south.It was concluded from above results that the geostatistical method could be successfully used in the analyses of soil nutrient spatial variability in the area with medium size as the region of saline soil in Jiangsu coastal area. And it could also supply important theory basis for the environmental quality appraisement of saline soil.