基于GIS的兴宁市油茶种植适宜性评价

Suitability Evaluation of Camellia Cultivation Based on GIS in Xingning City

为探讨气候、地形、土壤条件等对兴宁市油茶种植生态适宜度的影响，提高兴宁市油茶种植生态区划的精细化程度，文章基于油茶生长对环境条件的需求，在充分分析兴宁市气候、地形、土壤条件的基础上，提出油茶种植综合区划指标为：4个气象因子（10—12月平均温度、1月平均气温、7月平均气温、8—9月平均降雨量）、3个地形因子（海拔高度、坡度、坡向）、3个土壤因子（有机质、pH值、全氮）；采用层次分析法和加权指数求和法，建立油茶种植的综合区划评估模型；基于GIS技术开展兴宁市油菜种植适宜性精细化区划。结果表明：兴宁市油茶适宜种植区主要分布在北部和东部海拔在100～500m的地区，约占全市总面积的37％，较适宜区主要分布在海拔高度在500～800m的低山区，约占全市总面积的44．2％，不适宜区主要分布在海拔≥800m的山区和海拔≤100m的中部地区，约占全市总面积的18．8％。

A comprehensive regionalization of Camellia cultivation can provide a scientific basis for the optimal distribution of Camellia in Xingning. In this paper four climate factors （the mean temperature from October to December, the mean temperature of January, the mean temperature of July and the average rainfall from October to September）, three terrain factors （altitude, aspect and slope） and three soil factors （soil organic matter, total nitrogen and pH value） were selected in the comprehensive regionalization model. Methods of the exponential weighted algorithm and analytic hierarchy process （AHP） were adopted to establish the evaluation model of Camellia in Xingning. The distribution of suitability of camellia was evaluated by GIS. The results indicated that the suitable, sub-suitable and unsuitable regions for Camellia cultivation accounted for 37%, 44.2% and 18.8% of the total area of the city, respectively. The suitable region was mainly distributed at the altitude of 100-500 m in the north and east of Xingning. The sub-suitable region was mainly distributed below the altitude of 800 m in the low mountains. The unsuitable region was mainly distributed below the altitude of 100 m in the plains and the high mountains which was higher than the altitude of 800 m. The evaluation of the planting suitability by GIS would provide a technical support for the rational planning of Camellia in Xingning.