基于景观格局的FAST宁静区生态风险时空演变分析

Spatial and temporal evolution of ecological risk in FAST Radio Quiet Zone based on landscape pattern

为揭示FAST工程的建成对宁静区及区内不同圈层生态环境的影响,并为区域未来的生态保护和风险防范提供一定参考,以2000、2010、2020年土地利用数据为基础,利用景观干扰度和脆弱度指数构筑评价模型来分析该区域2000~2020年景观格局及生态风险的演变特征.结果表明:林地、草地、耕地为FAST宁静区的优势景观类型,前10a景观变化以草地、耕地向林地转化为主,人类活动相对较弱;后10a建设用地快速增加,三个圈层综合动态度皆有所上升,景观变化渐活跃但仍处于较低可控水平;FAST宁静区以低、较低、中生态风险区为主,核心区、中间区生态风险低,但受FAST工程影响有上升趋势,边远区生态风险变化表现为“两极下降,中间升高”的纺锤状;FAST宁静区生态风险呈空间正相关且相关性越渐显著,分布特征以“高-高”聚集和“低-低”聚集为主.

Based on the land use data in 2000,2010 and 2020,the evaluation model was constructed by using the landscape disturbance index and landscape vulnerability index to analyze the change characteristics of landscape pattern and ecological risk in the region in the past two decades,so as to reveal the impacts of the completion of the FAST project on the ecological environment of different circles in this region.The purpose was to provide some reference for the future ecological protection and risk prevention in this region.The results showed that:woodland,grassland and cultivated land were the dominant landscape types in FAST Radio Quiet Zone.From 2000 to 2010,the landscape changes were mainly from grassland and cultivated land to woodland,and human activities were relatively weak.From 2010 to 2020,the construction land increased rapidly,the comprehensive dynamic attitudes of the three circles increased,and the landscape pattern changed gradually active but still at a low controllable level.The study area was mainly composed of low ecological risk area,lower ecological risk area and medium ecological risk area.The ecological risk was low in both the core area and the middle area but had an increasing trend under the influence of the FAST project,while the risk change in the remote area showed a spindle shape of"decreasing at the poles and increasing in the middle".The ecological risk in the study area showed a spatial positive correlation and the correlation became more and more significant.The distribution characteristics were mainly"high-high"aggregation and"low-low"aggregation.