基于GIS和FCM的宁乡植烟土壤养分管理分区

采用GPS、地统计学和模糊c均值聚类相结合的方法,对湖南省宁乡植烟土壤主要养分的空间变异特征和管理分区进行研究。结果表明,宁乡植烟土壤主要养分指标均为中等程度变异,有机质、有效磷和速效钾3项指标的块金效应在25%~75%之间,表明研究区域该3项养分指标是由结构性因素和随机因素共同作用的结果;碱解氮的块金效应75%,表明研究区土壤碱解氮主要由随机性因素决定。土壤有机质为高水平,碱解氮和速效钾均为中等水平,有效磷为极高水平,研究区大部分区域有机质、碱解氮、有效磷为中等至极高,但约有40%的面积土壤速效钾缺乏。宁乡烟区可划分为3个养分管理分区,分区间有机质、全氮、碱解氮和速效钾含量差异极显著。

Definition of Management Zones of Tobacco Soil Nutrients Based on GIS and FCM in Ningxiang

Base on GPS, geo-statistics and fuzzy c-mean algorithm, spatial variability and management zone of soil major nu-trients in tobacco fields in Ningxiang were studied. The results indicates that soil main nutrients were intermediate variability. The nugget to sill ratio of organic matter, available potassium and available phosphorus was 25%~75%, which was of moder-ate spatial dependence. Spatial variability of these 3 nutrients were caused by structural factors and random factors. And the nugget to sill ratio of alkali hydrolyzable nitrogen was >75%, which was of week spatial dependence. Spatial variability of al-kali hydrolyzable was caused by random factors. Soil organic matter was high level, alkali hydrolyzable nitrogen and available potassium and available phosphorus were moderate level. Available phosphorus was very high level. Most of study area organic matter, hydrolyzable nitrogen, total nitrogen, available phosphorus are moderate to extremely high, but about 40% of the area of soil available potassium deficiency. Ningxiang tobacco area could be divided into 3 nutrient management zone, there were very significant in organic matter, available potassium, available phosphorus and alkaline hydrolyzable nitrogen between management zone.