【摘要】 为了全面了解掌握张家界市两区两县土壤有机质含量状况,采用S型布点取样的方法对具有代表性的土壤类型进行采样,共采集土壤样品250个,并采用重铬酸钾外加热容量法进行有机质含量测定。结果表明,各地区土壤有机质含量差异很大,总变幅为7.20～51.16 g/kg,其中,以武陵源区土壤有机质含量变幅最大,变幅为16.00~51.60 g/kg;其次为桑植县,变幅为11.10～39.90 g/kg;永定区与慈利县变幅相差不大,分别为7.23～36.30 g/kg和7.50～32.00 g/kg。不同土壤类型对土壤有机质的影响较大,含量最高的为黑色石灰性土壤,平均含量为36.30 g/kg;最低的为紫色土和山地棕壤,平均含量为16.07,16.10 g/kg。62.40%的土壤有机质含量变幅在20～30 g/kg之间。更多还原

【Abstract】 To understand the condition of soil organic matter contents in two counties and two districts of Zhangjiajie,250 samples were taken by the method of S-distribution from representative soil types and their organic matter contents were determined by the potassium dichromate-volumetric outside heating method.The results showed that the soil organic matter contents had significant differences between areas,and the total soil organic matter content ranged from 7.20 to 51.16 g/kg,in which the variation scope of soil organic matter content ranged from16.00~51.60 g/kg.The differences in Wulingyuan District was the biggest,and the next was in Sangzhi county that ranged from 11.10 to 39.90 g/kg;the content variations in Yongding and Cili county were less,ranging from 7.23~36.30 g/kg and from 7.50~32.00 g/kg respectively.The different soil types had a big influence on soil organic matter content,among which the calcareous soil had the highest soil organic matter content,average content of 36.30 g/kg,the lowest was purple soil and brown soil in mountain area,their average content were 16.07 g/kg and 16.10 g/kg respectively.Additionally,there was 62.40% soil in which the organic matter content ranged from 20~30 g/kg.The object of this study was to provide a theoretical basis for protection and utilization the limited soil resources.更多还原