天津市自然保护地与区域生境质量的时空演变格局

Spatio-temporal evolution pattern of protected areas and regional habitat quality in Tianjin

生境质量是反映区域生物多样性水平的重要指标,而规划科学、管理有效的自然保护地对于维护生境质量、巩固区域生态安全具有重要作用。以天津市为例,运用InVEST模型Habitat Quality模块评估了天津市2000、2005、2010、2015、2018年生境质量时空变化格局,基于叠加分析自然保护地内外生境质量变化探讨自然保护地对维护区域生境质量发挥的作用。结果表明:(1)2000—2018年间天津市生境质量总体下降了13.18%,并呈现出明显的由中心城区向环城四区扩散的趋势,高质量区域仅占天津陆域国土面积的4%,主要分布在天津北部山区和于桥水库、团泊洼、北大港、大黄堡等湿地。(2)天津保护地空间分布上呈集中分布态势,覆盖了天津市约75%的高质量生境区域和25%的较高质量生境区域。(3)从整体上看不同类型的自然保护地内生境质量保护效果不同,自然保护区优于其它类保护地,其生境质量明显得到提升。所有保护地中有10处保护地生境质量略有下降,但低于全域下降水平,只有盘山风景名胜区和古海岸与湿地自然保护区生境质量下降高于全域平均水平。(4)自然保护地对天津市生境质量下降的趋势起到了一定缓冲作用,其内部生境质量变化的绝对量和相对量均显著优于区外5 km缓冲带(P<0.1)。因此建议进一步提高保护地管理水平,加强管控力度充分发挥自然保护地保护效能。

Habitat quality is an important indicator reflecting regional biodiversity.The scientific planning and effective management of the protected areas play an important role in maintaining habitat quality.In the current study,we evaluated the spatial pattern and temporal dynamics of the habitat quality in Tianjin in 2000,2005,2010,2015 and 2018 by InVEST-Habitat Quality model.Then we compared such pattern changes inside and outside the nature reserve to discuss the role of Nature Reserve in maintaining regional habitat quality.The results show that:(1)from 2000 to 2018,the overall habitat quality in Tianjin decreased by 13.18%,showing an obvious trend of diffusion from the central urban area to the periphery.The higher-quality area only accounted for 4%of the land area,which mainly distributed in the north mountainous areas and wetlands such as Yuqiao Reservoir,Tuanbowa,Beidagang,and Dahuangbao.(2)The spatial distribution of Tianjin protected areas was aggregated,covering about 75%of the higher-quality habitat areas and 25%of the high-quality habitat areas.(3)The effectiveness of habitat quality in different types of protected areas were different.Nature reserves,which habitat quality have been significantly improved,were better than other types of protected areas.Habitat quality of 10 protected areas decreased slightly(but lower than the overall decline level).Only the habitat quality of Panshan scenic spot and Ancient Coast and Wetland Nature Reserve decreased higher than the overall average level.(4)The nature reserve played a role in buffering the declining trend of habitat quality in Tianjin.The absolute and relative changes of habitat quality inside the nature reserve were significantly better than those outside the 5 km buffer zone(P<0.1).Therefore,we suggest to improve the management of protected areas,strengthen protected powering,and give full authority to the managers of protected areas.