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2007年采集了崇明三岛(崇明岛、长兴岛和横沙岛)土壤表层(0~20cm)土样135个,测试和分析了其中有机质、全氮、有效磷和有效钾的含量.在ArcGIS9.1平台上,运用地统计学和叠置分析等方法,研究了土壤主要养分空间分布特征.结果表明,崇明土壤全氮和有机质含量总体上呈条带状或斑块状分布,以城桥镇和堡镇为两个高值中心,分别向西北和东北逐渐递减.有效磷和有效钾含量分别呈现斑块状和条带状分布,且二者的分布基本呈互补趋势(有效磷含量高的地方一般有效钾含量很低).与1980年数据相对比,土壤有机质和全氮含量在20多年来没有明显变化,而有效磷含量明显升高,有效钾含量有所降低.这表明崇明三岛存在一定程度的施肥结构不合理的问题.
In 2007, 135 soil samples (0 ~ 20cm) from Chongming Island, Changxing Island and Hengsha Island were collected and their contents of organic matter, total nitrogen, available phosphorus and available potassium were measured and analyzed.At ArcGIS9 .1 platform, using the methods of geostatistics and overlay analysis, the spatial distribution characteristics of soil nutrients were studied.The results showed that the soil total nitrogen and organic matter content in Chongming were generally strip-like or patchy distribution, The town and town are two high value centers, which decrease gradually to the northwest and northeast, respectively.The available phosphorus and available potassium content show patchy and banded distribution, and the distribution of the two is basically complementary (the content of available phosphorus is high Of the total available potassium is very low.) Compared with the data of 1980, the content of soil organic matter and total nitrogen did not change significantly in 20 years, but the content of available phosphorus increased obviously and the content of available potassium decreased, Island there is a certain degree of unreasonable fertilization structure.