甘肃省不同生态功能区草地资源综合评分及其原因分析

Comprehensive scores of grassland resources in different ecological functional areas of Gansu Province and their causes

根据甘肃省自然气候的地域分异性规律,将全省草原划分为甘南高寒草原生态功能区,祁连山-阿尔金山山地草甸、草原生态功能区,河西走廊荒漠草原生态功能区,黄土高原干旱草原生态功能区,陇南山地草丛草原生态功能区5个草原生态功能区。从甘肃省林草资源现状数据库中,提取草地图斑和相关属性因子,形成草原专题数据库。分别计算全省5个草原生态功能区的草原综合植被盖度、单位面积牧草产量、可食牧草占比、草原载畜能力4个指标。结果表明,通过加入权重系数计算求得全省草原不同生态功能区草地资源综合分析评价得分,并对计算结果采取百分制赋分,得分最高的陇南山地草丛草原生态功能区赋值100分,则甘南高寒草原生态功能区百分制得分为94.11分,黄土高原干旱草原生态功能区百分制得分为50.41分,河西走廊荒漠草原生态功能区百分制得分为26.07分,祁连山-阿尔金山山地草甸、草原生态功能区百分制得分为18.36分。

According to the regional differentiation law of natural climate in Gansu province,the grassland in Gansu province was divided into five grassland ecological function zones:Gannan alpine grassland ecological function zone,Qilian Mountain-Aljinshan mountain meadow,grassland ecological function zone,Hexi Corridor desert grassland ecological function zone,Loess Plateau arid grassland ecological function zone,Longnan mountain grass grassland ecological function zone.From the current forest and grassland resources database of Gansu Province,the grassland map spots and related attribute factors were extracted to form the grassland thematic database.Four indexes of grassland comprehensive vegetation coverage,forage yield per unit area(kg/hm~2),edible forage ratio(%) and livestock carrying capacity(hm~2/sheep per unit · year) were calculated in the five grassland ecological function zones of the province.The results showed that the scores of comprehensive analysis and evaluation of grassland resources in different ecological functional areas were obtained by adding weight coefficients,and the calculated results were assigned 100 points.The highest score was assigned 100 points to the ecological functional area of Longnan mountain grassland.The ecological function zone of Gannan alpine grassland was 94.11 points.The ecological functional area of arid grassland on the Loess Plateau was 50.41 points.The ecological function zone of desert steppe in Hexi Corridor was 26.07 points.The ecological function zone of the grassland and meadow in Qilian Mountains and Altun Mountains was 18.36 points.