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采集了崇明三岛土壤表层(0~20 cm)土样135个,测试了其中有机质、全氮的含量,在ArcG IS 9.1平台上运用地统计学、叠置分析等方法,研究了土壤有机质和全氮的空间分布特征及其影响因素.结果表明,崇明三岛土壤全氮和有机质含量总体水平偏低,全氮平均值为(0.93±0.47)g.kg-1,有机质平均值为(18.97±9.27)g.kg-1,全氮和有机质变异系数分别为0.509 6,0.488 6,均属中等变异程度.土壤全氮分布的理论模型为球状模型,有机质分布模型为高斯模型,其块金值和基台值之比分别为0.625和0.653,都为中等程度空间相关.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,城镇地区呈现以城桥镇和堡镇为2个高值中心向周围逐渐递减的趋势,西沙、东滩和北湖地区含量最低.土壤全氮和有机质含量的空间分布与崇明垦殖和培肥历史表现出较密切的相关性,且表现出一定的城镇效应.
A total of 135 soil samples (0 ~ 20 cm) from Chongming Island were collected and their contents of organic matter and total nitrogen were tested. Using the methods of geostatistics and overlay analysis on the ArcGIS 9.1 platform, the effects of soil organic matter and The results showed that the soil total nitrogen and organic matter content in Chongming Island was generally low, the average value of total nitrogen was (0.93 ± 0.47) g.kg-1, and the average value of organic matter was (18.97 ± 9.27) g · kg-1, and the coefficients of variation of total nitrogen and organic matter were 0.509 6 and 0.4888, respectively, all of them were moderately variable.The theoretical model of soil total nitrogen distribution was a spherical model and the organic matter distribution model was a Gaussian model, And the ratios of the values to the abutment values were 0.625 and 0.653 respectively, which were all moderately spatial correlations.The content of total nitrogen and organic matter in Chongming soil was generally strip-like or patchy distribution, 2 high value centers gradually decreased toward the periphery, and the lowest was in Xisha, Dongtan and Beihu regions.The spatial distribution of soil total nitrogen and organic matter showed a close correlation with the history of Chongming reclamation and fertilization and showed certain The town effect.