Research On Land Suitability Evaluation For Tobacco In Luoyang

Based on the integrated comment of the theories, methods and researches statues of land use evaluation (land suitability evaluation) at home and abroad, and according to the methods of FAO"A Frame work for land Evaluation", the paper expounded the interrelation between land conditions and tobacco growth through the investigation, analysis and evaluation of the climate, terrain, soil and tobacco samples in Luoyang. Then it took MAPGIS and ARCVIEW system as the technological platform, the unit overlaped by multi-maps as the evaluation cells,and according to the evaluation indexes and weights get by Delphi method and the synthetical indexes of land suitability evaluation calculated by Exponential Sum method, the cultivated land in Luoyang were divided into four suitable grade,and different kind of achievement graphs were compilated. Finally, a allocation of the tobacco production blueprint arrangement in Luoyang was drawed up and some suggestions about how to fertilize were gived based on the results to direct local tobacco production. The main study results are as follows:The aerial temperature and the illumination are good for tobacco growth in Luoyang except for Luanchuan County. The precipitation is slightly fewer and relatively concentrated during the field growth period of tobacco. Analysis of soil attributes shows that soil organic content, readily available nitrogen, chlorine ion content are suitable or a bit lower and soil pH, available calcium, available sulphur, available magnesium are higher than tobacco's needs; while soil readily available phosphorus and most microelement are widely lack. The tobacco chemical element contents are slightly different in the district, while the appraisal of tobacco smoking quality has great difference in recent years.Land suitability evaluation result indicates as follows, the acreage of the I grade land is 171177.2 ha, about 40.69% of the total land and mainly distribute on red claysoil and cinnamon soil in Yiyang, Luoning, Xin'an and Songxian. The acreage of the II grade is 122328.34 ha, about 29.08% of the total land and chiefly distribute on cinnamon soil and fluvo-aquic soil in Yichan, Yanshi, Ruyang and Yiyang. The acreage of the III restrictive grade is 112485.12 ha, about 26.74% of the total land and mostly lies in Mengjin and Yanshi on cinnamon soil, fluvo-aquic soil, skeletal soil and brown soil. The acreage of the IV ill-fitted grade is 14721.82 ha, about 3.50% of the total land and distribute on Songxian and Luanchuan on cinnamon soil, purple soil and fluvo-aquic soil. Additionally the acreage of the cultivated land of different grades on different soil genus or in different townships was summed upand analysed.On the basis of land suitability evaluation of tobacco in Luoyang and according to the principle of "stress the key points, centralized in flakes, convenient management and easy to put into effect", cultivated land of Luoyang was devided into four different tobacco plantation zones. It contains the Xiao mountain high-quality tobacco zone, the Xiong 'er mountain high-quality tobacco zone, the Xiong'er-Waifang mountain high-quality tobacco zone, the central highland tobacco zone and the restrained tobacco zone.