黎恒明+杨苗苗

摘 要：为了评价汉江中游典型小流域土壤有效锌的分布特征，利用网格法分3层在余姐河小流域采集土样，共采集207个样点。基于地统计学方法和Kriging插值法，结合坡向对土壤有效锌含量空间变异特征进行研究，并进行了丰缺评价。结果表明：随着土层深度的增加，土壤有效锌含量逐渐降低；经方差检验，仅0～10 cm土层土壤有效锌含量存在显著性差异；林地0～10、20～40 cm土层土壤有效锌含量与坡向呈显著正相关关系；草地0～10 cm土层土壤有效锌含量与坡向呈显著负相关关系，10～20、20～40 cm土层呈极显著负相关关系；该流域0～10 cm土壤有效锌储量为45.42 kg，土壤有效锌储量从大到小依次为林地、农地、草地；根据土壤有效态微量元素平均密度综合评价指数，该流域土壤有效锌处于丰富水平。

关键词：有效锌；空间变异；地统计学；Kriging插值法；土地利用方式；坡向；汉江

中图分类号：S153.6 文献标志码：A

文章编号：1672-6561（2016）05-0700-08

Abstract： In order to evaluate the distribution characteristics of soil available zinc in a typical small watershed of the middle Hanjiang River， the 207 soil samples were collected with the depths of 0-10， 10-20， 20-40 cm in Yujiehe small watershed by the means of grid method. Based on geostatistics and Kriging interpolation， combined with the effect of aspect， the spatial variation characteristics of soil available zinc were discussed， and the abundance of soil available zinc was evaluated. The results show that the content of soil available zinc decreases with the increase of soil depth； according to the variance test， the differences of spatial variations of content of soil available zinc at 0-10 cm soil depth are significant； the correlation of content of soil available zinc and aspect for forestland is significant and positive in 0-10， 20-40 cm soil depths； the correlation of content of soil available zinc and aspect for grassland is significant and negative in 0-10 cm soil depth， and extremely significant and negative in 10-20 and 20-40 cm soil depths； the storage of soil available zinc is 45.42 kg in 0-10 cm soil depth， and there are forestland， cropland and grassland in descending order； According to the comprehensive evaluation index of average density of soil available trace elements， the soil available zinc is rich in Yujiehe small watershed of the middle Hanjiang River.

Key words： available zinc； spatial variation； geostatistics； Kriging interpolation； land use type； aspect； Hanjiang River

0 引 言

锌是植物生长所必需的微量元素之一，能促进植物光合作用、酶、生长素、蛋白质和核酸的合成，还可以提高植物的耐寒和抗病能力[1]。在无人为施用锌肥的情况下，植物所需锌（有效态）的供给主要来源于土壤，故有效态的锌在一定条件下表征土壤锌元素的供给水平。土壤有效锌含量受土壤性质、成土过程和农耕活动等因素影响，空间分布不均匀，对植物的生长造成一定影响。科学区划有效锌含量范围对于作物生长及土壤生态环境保护十分必要。土壤有效锌含量的空间变异性研究是科学区划的基础。……