西南地区页岩气开采区生态系统时空变化特征研究

Ecological changes and regional differences of shale gas exploitation areas in Southwest China.

页岩气的勘探开发将极大地缓解我国天然气需求压力,优化调整我国的能源格局,保障国家安全。然而页岩气开发会对生态环境产生影响。通过研究2000、2010和2020年我国页岩气重点建产区中长宁、威远和涪陵3个片区生态系统格局及水淹频度时空变化特征,对重点建产区内开采前、开采初期及规模开采后生态环境变化的整体性和差异性进行研究,主要有以下结论:1)根据3个片区生态系统格局20年来的整体变化可以看出,3个片区生态空间呈现不同程度萎缩,其中威远片区最为显著,涪陵片区次之,长宁片区减少最小。同时,3个片区城镇生活空间面积都有大幅增加,其中增加最为显著的是涪陵片区,长宁片区次之,威远片区增加幅度最小。2)2000年至2020年,长宁片区由生态空间转为城镇生活空间的转移量最大,零散分布于片区内,南部比北部更密集;涪陵片区转移量略低于长宁片区,集中分布在市区周围或沿河道两侧;威远片区转移量最小,分布在片区内几个主要城市周围,属城镇扩张现象。3)20年来研究区域内季节性水体消失明显,其中低水淹频度区域占比总体减少了68.56%,在后10年急剧减弱;中水淹频度区域占比总体减少了56.94%,同样是后10年减弱趋势更加明显。研究区域内永久性陆地及高水淹频度区域均呈现增加态势。由此可见,20年来区域内水路交替强度减弱,稳定陆地和水体的同时增加有可能是受到人为活动的影响。4)将多年生态系统格局变化转移情况和水体变化转移情况进行叠加分析可知,研究区内由于城镇生活空间扩张导致季节性水体消失的比例较小,季节性水体变化区域主要集中在农业生产空间中。

The exploration of shale gas greatly relieved the pressure on China s natural gas demand,adjusted China s energy pattern and ensured national security.However,shale gas exploration brought impacts on ecological environment.This paper analyzes the ecosystem pattern and water inundation frequency spatial and temporal variation characteristics between 2000 and 2020 of in Chinese key shale gas production areas.The main conclusions are as follows:1)The ecological space of the three areas has shrunk with varying degrees,and Weiyuan has the most significant reduction living spaces of the three areas have increased significantly,Fuling is the most significant increase.2)The largest amount of transfer from ecological space to living space is Changning,which is scattered in the area,and the southern is more dense than the northern;Fuling is slightly lower than Changning,and is concentrated around the or both sides of the river;Weiyuan has the smallest amount of transfer,which is distributed around several major cities in the area,belonging to the phenomenon of expansion.3)The seasonal water bodies in the past 20 years disappeared obviously,which the proportion of low inundation frequency areas decreased by 68.56%;the proportion of medium inundation frequency area decreased by 56.94%.Both the permanent land and high inundation frequency area showed an increasing trend.In the past 20 years,the intensity of water and land alternation has weakened,and the increase in the stability land and water may be affected by human activities.4)Based on the analysis of the change and transfer of ecosystem pattern,the proportion of seasonal water body disappearing due to the expansion of living space is small,and the seasonal water change area is mainly concentrated in the agricultural production space.