基于气候适宜性指数的重庆三峡库区五种牧草精细气候区划OA

To precisely characterize the spatial distribution of climate suitability for pasture cultivation in the Chongqing section of the Three Gorges reservoir area(TGRA),a comprehensive assessment was conducted.Daily meteorological data from 1058 observation stations from 2011 to 2020,a 30-meter digital elevation model(DEM),and climatic suitability indicators for five commonly cultivated pasture species were integrated.Eight factors,including mean annual temperature,accumulated temperature above 0℃,extreme temperature,mean annual precipitation,sunshine duration,frost-free period,mean relative humidity and elevation,were selected as zoning indicators.These indicators were spatialized using interpolation methods,and a new Pasture climate suitability index(PCSI)was constructed based on fuzzy mathematics and a weighted comprehensive evaluation method.Natural breaks(Jenks optimization)were used to classify climate suitability into three levels:suitable,sub-suitable and unsuitable,while areas categorized as other refer to water bodies and built-up land excluded from the suitability evaluation.The results showed that the PCSI values across the TGRA ranged from 0.47 to 0.76,with suitable areas(0.72-0.76)and sub-suitable areas(0.66-0.72)accounting for 65.0%and 32.2%of the total area,respectively,indicating favorable climatic conditions for pasture growth in most of the region.All five pasture species exhibited a relatively high level of climatic adaptability.In terms of overall suitability,the ranking from highest to lowest was:alfalfa>hybrid giant napier>sweet sorghum>annual ryegrass>napier grass.Although the spatial suitability patterns of the five species were generally consistent,there were regional differences in the proportions of suitability classes.Suitable and sub-suitable zones were widely distributed,while unsuitable areas were mainly located in the northern,eastern,southwestern and some southern high-altitude regions of the TGRA.The largest Suitable area proportion was observed for alfalfa(57.9%),while the highest proportion of unsuitable areas occurred for annual ryegrass(18.0%)and the lowest for alfalfa(6.7%).