1998-2018年呼伦贝尔市植被覆盖度时空变化及驱动力分析

Abstract

呼伦贝尔市作为中国北方的重要生态屏障，其生态状况的变化及影响因素一直备受关注。基于1998-2018年SPOT/VEGETATION NDVI数据，结合地形、气候和社会经济数据利用像元二分模型、趋势分析法，并根据数据特点，综合多种统计方法，对呼伦贝尔市植被覆盖度（FVC）时空变化及驱动力进行定性与定量分析。结果表明：（1）21年间研究区FVC在低波动中缓慢增长，以4-5年为周期，周期内FVC先减少后增长，在空间上呈"西减东增"的变化格局；（2） FVC类型以极高和高为主，中、低、极低面积依次递减且总和仅占10%-15%，FVC增加、变化不显著及减少区域面积分别为135720.57 km²（53.56%）、107140.74 km²（42.28%）、10569.06 km²（4.17%）；（3）地形因素奠定了FVC"西低东高"的空间分布格局，气候和人类活动因素影响FVC的年际变化。位于研究区西南部的新巴尔虎右旗、新巴尔虎左旗、鄂温克族自治旗、陈巴尔虎旗和东南部的阿荣旗以气候因素为主导，位于中部大兴安岭上的牙克石市、额尔古纳市、根河市和扎兰屯以人类活动因素为主导，满洲里、海拉尔和鄂伦春自治旗则受气候因素与人类活动因素的综合影响。驱动力因素对FVC变化的影响具有差异性和双向性，在合理的政策和规划下，可以实现社会经济发展与生态环境可持续发展的双赢。;With the rapid development of the global economy, the ecological environment is deteriorating, and it is urgent to carry out environmental change monitoring. The rise of remote sensing technology has made it possible. As an important ecological barrier in northern China, Hulunbuir City has been receiving much attention. Currently, the ecological environment monitoring of Hulunbuir focuses on the use of multi-period remote sensing images, combining with climate data, and a single driving force analysis method to study the changes in local vegetation and to explore the response of vegetation changes to the natural climate. However, there are few studies on the impacts of human activities on vegetation changes. Most of them are based on qualitative analysis or human activities as a whole, which is difficult to determine the specific driving force components and the influence direction and the extent of each component factor. This paper is based on SPOT/VEGETATION NDVI data from 1998-2018, combined with the terrain, climate and Human activity data, and comprehensively applying the trend analysis, coefficient of variation method, pixel decomposition model, principal component analysis, multiple linear regression, ridge regression and so on to carry out the qualitative and quantitative analysis of the spatio-temporal changes and driving forces of Hulunbuir's fraction of vegetation cover (FVC). The results show:(1) during the 21 year, the FVC in the study area slowly increases in low fluctuations, with a period of 4-5 years, during which the FVC first decreases and then increases, and there is a change pattern of decreasing in the west and increasing in the east in space. The FVC types are mainly extremely high and high, and the areas of medium, low, and extremely low are decreasing, and the sum only accounts for 10%-15% of the study area. The increase of extremely low and low type area is relatively large, which are 36.80% and 98.46%, respectively. The main source is the degradation of medium and high type, and the increase of extremely high type area is relatively large, which is 33786.03 km², and the main source is the further improvement of high type. (2) The areas with significant and extremely significant increases account for 53.56% (135720.57 km²), the areas with insignificant changes account for 42.28% (107140.74 km²), and the areas with significant and extremely significant decreases only account for 4.17% (10569.06 km²) of the research area. (3) There are obvious differences in the driving force of the FVC in different regions. Topographical factors lay the spatial distribution pattern of low west and high east and climatic factors affect the temporal distribution pattern of FVC. New Barag Right Banner, New Barag Left Banner, Ewenki Autonomous Banner, Arun Banner and Chen Barag Banner are dominated by climatic factors. Yakeshi, Erguna, Genhe City and Zhalantun is dominated by human activities factors, while Manzhouli, Hailar and Oroqen Autonomous Banner are affected by climatic factors and human activities factors. The influence of driving factors on Hulunbuir's FVC changes is bidirectional. With the correct policies and reasonable planning, it is possible to achieve a win-win situation for socio-economic development and sustainable development of the ecological environment. The research results provide the theory and data support for Hulunbuir's sustainable development of ecological environment and grassland protection policy.