西藏地区耕地种植紫花苜蓿的气候适宜性区划

Climatic suitability regionalization of alfalfa cultivated in farmland in Tibet

【目的】研究西藏地区耕地种植紫花苜蓿的气候适宜性区划,能够为西藏充分利用耕地资源和气候资源,合理布局紫花苜蓿生产提供一定的科学依据.【方法】以西藏自治区河谷地带的耕地为研究对象,以西藏自治区及其周边38个气象站1971~2010年的气象数据为数据源,利用层次分析法确定≥0℃年积温、年均温度、年降水量和湿润度4个指标的权重,在Arc Map平台上对紫花苜蓿种植的气候适宜性进行分级,并与2018年西藏自治区的耕地数据叠加,绘制西藏地区耕地种植紫花苜蓿的气候适宜性区划图.【结果】研究结果表明:≥0℃年积温对紫花苜蓿的适宜性影响最大,年降水量、年均温度和湿润度次之;在西藏地区耕地种植紫花苜蓿的气候适宜区主要分布在拉萨市、昌都市、日喀则市、林芝市和山南市.【结论】在西藏地区的耕地中种植紫花苜蓿要重视温度和降水量因素,适宜种植紫花苜蓿的地区要充分利用当地的耕地资源和气候资源,在保证粮食安全的前提下可以调整一部分耕地种植紫花苜蓿,建立人工饲草生产基地.

【Objective】Study on climatic suitability regionalization of alfalfa cultivated in farmland in Tibet can provide scientific basis for reasonable alfalfa production with abundant climatic resource and limited farmland in Tibet.【Method】The farmland located in the river valley in Tibet was taken as study object,and the meteorological data distributed in and around Tibet during 1971~2010 was considered as data source in this study.The methods of Analytic Hierarchy Process and Judgment Matrix were applied to simulate the weight of four indexes including≥0℃accumulated temperature,annual average temperature,annual precipitation and humidity.In order to map the climatic suitability regionalization of alfalfa cultivated in farmland in Tibet,the climatic suitability of alfalfa was classified and further was intersected with farmland data in Tibet during 2018 in Arc Map.【Result】The results showed that≥0℃annual accumulated temperature,annual precipitation,annual average temperature and humidity impacted on suitability of alfalfa from greatest to smallest.The climatic suitability regions for cultivating alfalfa in farmland in Tibet mainly distributed in Lhasa,Changdu,Rikaze,Linzhi and Shannan.【Conclusion】The temperature and precipitation should be paid more attention when the alfalfa is cultivated in farmland in Tibet.The locally abundant climatic resource and limited farmland should be fully used in the farmland where is suitable for cultivating alfalfa.Some farmland can be adjusted to cultivate alfalfa and further to build artificial forage production station.