湘西植烟土壤有效锌时空变异及影响因素研究

Temporal and spatial variation characteristics of available Zn in tobacco planting soil in Xiangxi

2000和2015年在湘西烟区采集土壤样品,测定土壤有效锌含量,利用经典统计学、地统计学等方法,对区域土壤有效锌时空变异及其影响因素进行研究。结果表明:就基本统计特征而言, 15年间湘西植烟土壤有效锌含量均值由1.10 mg·kg^-1上升到3.41 mg·kg^-1,增幅达210%;就时空变异而言, 15年来土壤有效锌块金效应增大,随机因素对土壤有效锌空间变异的影响有所增强。就时空分布的变化而言, 2015年土壤有效锌含量等级为"高"和"极高"的面积大幅度增加,分别增加50.06%和19.59%,而等级为"低"和"适宜"的面积大幅度减少,较2000年分别下降57.78%和11.78%。目前在湘西7个植烟县中,泸溪县植烟土壤有效锌适宜比例最高,花垣县最低。相关分析结果表明海拔高度、地形地貌、成土母质、土地利用方式、轮作制度及土壤有机质对土壤有效锌含量均有较大影响。

In order to explore the temporal and spatial variation characteristics of effective zinc(Zn) in Xiangxi tobacco soil and provide scientific basis for the management of Zn nutrition in Xiangxi tobacco area, the soil samples were collected and the content of effective Zn was measured in the Xiangxi tobacco area in 2000 and 2015 respectively. The temporal and spatial variation of available Zn in the soil and its influence factors were analyzed by the methods of classical statistics and geostatistics. The results showed that from the basic statistical characteristics, the average amount of effective Zn in Xiangxi tobacco growing soil increased from 1.10 mg·kg^-1 to 3.41 mg·kg^-1 in the past 15 years, with an increase of 210%. From the temporal and spatial variation, the block gold effect of effective Zn was increased in 15 years, and the effect of random factors on the spatial variation of available Zn in soil was enhanced. In terms of temporal and spatial distribution, the area of "high" and "extremely high" levels of soil available Zn increased significantly in 2015, increased by 50.06% and 19.59% respectively, while the "low" and "suitable" grades decreased by 57.78% and 11.78%, respectively, compared with 2000. The content of available Zn in soil was closely related to altitude, topography, parent material, land use type, rotation system and soil organic matter.