基于3S的新疆阜康典型草地产草量及草畜平衡分析

Yield and animal-feed balance of typical grassland in Xinjiang Fukang using 3S techniques

以西北干旱半干旱地区典型代表城市——新疆阜康市为例,根据遥感影像、气象资料、年鉴和前人研究结果,利用遥感分类结果和产量估测模型计算了1990年、1999年和2008年的草地地上生物量,并结合牲畜数量计算了各年份的草畜平衡状态。结果表明,1)近20年研究区草地总面积和总产量均呈现持续下降的趋势,至2008年,牧草总产量较1990年减少了4.66%;2)1949-2008年,随着研究区年末牲畜存栏数的增加,1990年、1999年和2008年的可利用牧草总储量分别为3.77×105、3.64×105和3.63×105 t,这3年的草畜平衡状态为1990年和2008年分别欠载22.81%和4.91%,而1999年超载9.67%。结合研究区遥感分类图片、气候变化和牲畜存栏量分析可知,1990-2008年研究区农业开垦侵占草地导致草地地上生物量减少,加之年末牲畜存栏量的增加,单位面积草地载畜量压力加大,直至2005年前后实施退牧还草项目后,载畜量压力才得以缓解。草地生态和畜牧业要实现双赢发展,必须加大对草地生产力和牧区生产经营方式的实时监控力度。

The objective of this study is to calculate the grassland aboveground biomass （GAB） of Xinjiang Fukang in 1990, 1999 and 2008, using remote sensing images, meteorological data, the Yearbook, previous findings and classification results, the animal-feed balance and the number of animals were analyzed respectively. The results showed that, 1） in recent 20 years, the total area and aboveground biomass of pasture decreased consistently, the aboveground biomass in 2008 reduced by 4.66% compared to 1990; 2） the number of livestock continued to increase from 1990 to 2008, meanwhile total available forage reserves was 3.77×10^5t, 3.64×10^5t, 3.63×10^5t respectively. The animal-feed balance was as follows： the grass- land under-run was 29.6% in 1990, 4.91% in 2008, the overloaded was about 9.67% in 1999. Combined with the classification images, climate change and the amount of livestock, it was concluded that from 1990 to 2008, agriculture reclamation occupying grassland led to a reduction of GAB, meanwhile the amount of livestock increased yearly, which induced the pressure of carrying capacity per unit grassland. This situa- tion changed after the implementation of the grazing forbidden project in 2005. In order to develop grass- land ecosystem and livestock successfully, attention should be pay to increase the intensity of real-time monitoring of grassland productivity and manage pastoral production.