基于布迪科指标的中国植被-气候关系研究

Analyzing Vegetation-Climate Interactions in China Based on Budyko's Indices

根据中国418个气象站资料,计算了布迪科(Budyko)分类系统的净辐射和辐射干燥度指数,绘制了各气候指标在中国的分布图。结合中国植被区划图,绘制了中国8个植被地带的净辐射和辐射干燥度指数的散点图,较好地表现了中国各植被类型与气候指标的关系和格局,包括寒温带针叶林,温带针阔叶混交林,暖温带落叶阔叶林,亚热带常绿阔叶林,热带季雨林、雨林区域,温带草原,温带荒漠,青藏高原高寒植被,并得到了中国各植被地带的气候指标范围及界限。通过分析可以看出,净辐射的等值线较好地反映了中国大陆的热量梯度,而辐射干燥指数则较好地反映了中国大陆的干湿梯度。综合水热指数与中国植被主要类型的对应也较好,通过KAPPA检验,结果表明净辐射和辐射干燥度指数与中国植被主要类型及其分布格局密切相关,两者结合可以进行宏观尺度上植被类型的划分。

According to the records of 418 meteorological stations, the net radiation and the radiative index of dryness of Budyko＇ s classification system were index in China have been drawn. Connecting with graphs of net radiation and the dryness index of 8 calculated, and the maps of distribution of Budyko＇s map of vegetation classification in China, the scatter vegetation zones were drawn, which kindly show the relationship and pattern between vegetation types and climate in China. The vegetation types include cool-temperate （boreal） conifer forest, temperate mixed conifer-broadleaf forest, warm-temperate deciduous broadleaf forest, subtropical evergreen broadleaf forest, tropical rainforest and monsoon forest, temperate steppe, temperate desert and Tibetan-Qinghai plateau alpine vegetation. We got the range of climatic indexes of each vegetation zones in China. The calculation results show that the range of net radiation responding to the main vegetation types can be summarized as follows： cooltemperate conifer forest are 2 259.4MJ-2 384.9MJ·m^-2· a^-1 ; Cool-temperate mixed conifer-broadleaf forest are 2 343.1MJ·m^-2· a^-1 ; warm-temperate deciduous broadleaf forest are 2 761.5MJ-3 347.3MJ·m^-2· a^-1; subtropical evergreen broadleaf forest are 2 845.9MJ-3 347.3MJ·m^-2· a^-1 ; tropical rainforest and monsoon forest are more than 3 347.3MJ·m^-2· a^-1; temperate steppe are 2 384.9 MJ-3 012.6MJ·m^-2· a^-1; temperate desert are 2 301.3 MJ-3 012.6MJ·m^-2· a^-1; Tibetan-Qinghai plateau alpine vegetation are 3 012.6MJ-3 347.3MJ·m^-2· a^-1 And the range of radiation index of dryness corresponding to the main vegetation types of China could be summarized as follows： cooltemperate conifer forest are 2.1-4.3; Cool-temperate mixed conifer-broadleaf forest are 1.2-2.1; warm-temperate deciduous broadleaf forest are 1.6-2.8 ; subtropical evergreen broadleaf forest are 0.6 1.6; tropical rainforest and monsoon forest are 0.5 - 2.0; temperate steppe are 2.1-6.2; temperate desert are 〉 6.2 ; Tibetan-Qinghai plateau alpine vegetation are 2.8-23. The isolines of annual average net radiation relatively indicated the thermal gradient in China;the isolines of the dryness index showed the moisture gradient in China. And the map of integrating net radiation with dryness index shows better relation with vegetation types. Comparison between the prediction map and the map of vegetation classification were based on Kappa statistics and the values of Kappa statistics of 8 vegetation types are more than 40 percent. The comparison results indicate that the net radiation index and dryness index are significantly related to the types and distribution of main vegetations in China. The classification of vegetation types can be conducted on the basis of the combination application of both net radiation index and dryness index.