晋中地区荞麦品质气候区划的GIS多元分析

 探索荞麦的最佳生产布局,为优质荞麦生产的区域化、规模化提供理论和实践依据。本文分析了荞麦品质指标与气象因子的关系,结合荞麦地理分布,筛选影响各品质指标的主要气象因子,利用主成分分析法构建荞麦综合品质评价模型,并以ArcGIS软件的空间分析功能,对荞麦综合品质进行气候区划及区划评述。结果表明:温度、降水、日照时数等气象因子是影响各品质指标的主要因子。较高的均温和日最高温大于30℃时,对荞麦的生长有不良影响,不利于各品质指标的积累。而8月丰富的降水和生育期充足的光照有利于荞麦品质指标的积累。结合评价模型,利用GIS对荞麦综合品质进行区划,将晋中地区分为3个区,即适宜、次适宜、不适宜荞麦种植区,且各区与实际状况基本符合。利用主成分分析法和GIS进行荞麦品质气候区划是可行的,研究结果为荞麦的优质生产提供参考。

Climate Regionalization of Buckwheat Quality Index Based on GIS Multivariate Analysis in Jinzhong Prefecture

Buckwheat is mainly distributed in central and western regions in China, is one of the major food crops and economic crops in these areas. The production and development of buckwheat have direct impact on farmers＇ income and agricultural economic development of these areas. The climate regionaliza-tion of buckwheat quality is the important basis of optimizing cultivation environment and quality variety layout, and has a great guiding meaning towards high quality production of buckwheat. So, exploring the best planting pattern of buckwheat can provide theoretical and practical basis for the regionalization and high quality buckwheat production at larger scales. But the current climate regionalization studies of buck-wheat mainly focused on the suitable cultivation division using traditional research methods, and no report about climatic regionalization of buckwheat quality using principal components analysis （PCA） and GIS was found. In this study, the correlation of quality index of buckwheat and meteorological factors was an- alyzed, together with the geographical distribution information of buckwheat and the major meteorological factors which effected on quality index were screened out. The model was established based on PCA meth-od in order go assess the comprehensive quality of buckwheat, then the ecological regionalization was determined using the ArcGIS spatial analysis technique. The results showed that temperature, rainfall and sunshine--hour were the main ecological factors which effected buckwheat quality index. It had bad effect on buckwheat growth and went against accumulate of quality index, if the daily highest temperature was more than 35℃ and mean temperature was higher. A plenty of precipitation in August and plenteous sun-shine of whole stage were beneficial to accumulate of quality index. Combined with evaluation model, u-sing GIS, Jinzhong Prefecture was divided into three regions, i.e. adapted, inferior adapted and bad adap-ted planting region, and it was largely in line with the actual condition. PCA combined with GIS method is the most powerful approach for regionalization, and the quantitative computing and qualitative analysis are integrated. So, there is a feasibility to carry through ecological regionalization of buckwheat quality u-sing PCA method and GIS, and the regionalization results are objective and scientific. The method is con-cise, applicable and effective, which can really reflect the regionalization actual situation and provide refer-ence for fine quality production of buckwheat.