摘要
我国西北牧区绝大部分属于中温带干旱半干旱地区,其植被对环境变化极为敏感,也易受人类活动干扰。近年来,西北牧区植被发生了明显变化,影响了农牧业生产和生态建设。因此,亟需进一步掌握国家生态工程和种植业结构调整措施下西北牧区植被覆盖的动态变化特性,为农牧业生产和生态建设提供理论支持。利用1981—2015年8 km×8 km分辨率的GIMMS 3g NDVI产品,采用Theil-Sen Median趋势分析、Mann-Kendall检验与Hurst指数等方法,研究西北牧区植被覆盖的时空变化特性。结果表明：（1）1981—2015年,西北牧区植被覆盖发生了明显变化,改善面积占总面积的41.9%,其中,2006—2015年植被覆盖改善最明显,占比达到63.7%。（2）11种植被类型均呈恢复趋势,其中栽培植被改善面积占比超过80%,而草原和草丛改善超过60%。（3）35 a来,西北牧区植被覆盖呈正向可持续发展趋势,持续性恢复和稳定不变的面积占总面积的70%以上,其中,2006—2015年持续恢复和稳定不变的面积占总面积的63.8%。国家生态工程和种植业结构调整措施对西北牧区植被覆盖有明显影响,未来该区植被覆盖以持续性恢复为主。
The major parts of pastoral area in northwest China are generally the arid and semiarid regions,and the vegetation in this area is extremely sensitive to environmental change and susceptible to human activities. In recent years,the vegetation in the arid pastoral area is changed obviously,which is affected by the production of agriculture and animal husbandry and the ecological construction. Therefore,it is vital to further understand the vegetation variation in the pastoral area in northwest China,where the national ecological projects and planting structure adjustment of agriculture are implemented,and the theoretical supports are provided for the production of agriculture and animal husbandry and the ecological construction. In this study,the GIMMS 3 g NDVI product with a spatial resolution of 8 km × 8 km during the period from 1981 to 2015 was used to reveal the spatiotemporal characteristics of vegetation change in the study area with the Theil-Sen Median trend analysis,Mann-Kendall test and Hurst index.The results showed that the typical vegetation in the arid pastoral area was changed significantly during the period from 1981 to 2015,and the improved area accounted for 41. 9% of the total area. The improvement of vegetation was the most obvious from 2006 to 2015,and the improved area occupied 63. 7% of the total. All the 11 vegetation types were in a regenerating trend,in which the largest share came from cultivated vegetation,the improved area occupied more than 80% of the total,and the improved areas of pasture and hassock were over 60%. In the past 35 years,the vegetation coverage in the arid pastoral area was tended to a sustainable and positive development,and the proportion of continuously regenerating area was higher than 70% of the total. During the period of 2006-2015,the regeneration and stability occurred in 63. 8% of the total area. National ecological projects and planting structure adjustment of agriculture affect significantly the vegetation cover in the arid pastoral areas in northwest China. In the future,the vegetation coverage is supposed to be continuously restored.
作者
牟乐
芦奕晓
杨惠敏
冯琦胜
MOU Le;LU Yi-xiao;YANG Hui-min;FENG Qi-sheng(State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730020, Gansu, Chin)
出处
《干旱区研究》
CSCD
北大核心
2018年第3期615-623,共9页
Arid Zone Research
基金
国家重点研发计划课题(2016YFC0400302)
干旱气象科学研究基金项目(IAM201405)
中国气象局气候变化专项项目(CCSF201603)资助
