江苏重要生态功能区质量演变及红线管控效应

Analysis of quality evolution of important ecological function areas and implementation effects of the ecological redline in Jiangsu Province,China

生态保护红线区作为重要生态功能区,对国家生态安全起到了基础保障作用。如何准确有效地评估生态保护红线区生态质量演变以及生态保护红线的作用,对“红线”政策的进一步完善和区域可持续发展具有重要意义。基于Google Earth Engine平台,利用Landsat 5、8长时序遥感影像构建出江苏全域1985—2021年遥感生态指数RSEI,分析了生态保护红线区1985年以来的生态质量演变情况,评估了2013年以来实施的生态保护红线政策在生态保护方面的效用。结果表明:(1)针对江苏全域构建的RSEI模型PC1平均贡献率高于70%,适用于江苏全域及生态保护红线区的生态质量演变分析。1985—2021年RSEI提升的面积占江苏总面积的58.2%,红线区平均RSEI值在0.52—0.63间变化,整体呈现波动上升的趋势;(2)江苏生态保护红线区整体RSEI均值突变年份在2003年,各市红线区RSEI均值突变年份大多集中在1995—2005年间,1990年代苏南和苏中部分城市出现由好向差的突变,2000年代苏北城市出现由差向好的突变;(3)生态保护红线具有屏蔽效应,有效阻挡了建筑用地等不透水面和裸土向保护区侵蚀,红线区内RSEI增长趋势显著高于红线区外部。生态保护红线在具有较强经济实力的城市管控效应更加突出,13地市中南通、苏州、无锡、常州、镇江为生态质量明显提升城市,南京、徐州和泰州为加速提升城市,连云港和淮安为缓速提升城市,“红线”政策在宿迁、扬州和盐城的生态质量提升作用不明显。该方法改进后可用于生态保护红线监测与管控效应的业务化评估。

Ecological redline zone,as an important ecological function area,plays a fundamental role in guaranteeing the national ecological security.How to accurately and effectively assess the ecological quality evolution of ecological redline zone and the implementation effects is of great significance to further improvement of the"red line"policy and regional sustainable development.Based on the Google Earth Engine platform,Landsat 5 and 8 long-time sequence remote sensing images were used to establish a Remote Sensing Ecological Index(RSEI)for Jiangsu Province from 1985 to 2021,with which the quality change from 1985 in the ecological redline zone was analyzed and the role of ecological redline policy implemented since 2013 was assessed.The results showed that:(1)the average contribution rate of the RSEI model PC1 established for Jiangsu Province is higher than 70%,which applies to the analysis of the evolution of ecological quality in Jiangsu Province and the ecological redline zone.From 1985 to 2021,58.2%of the total area of Jiangsu was improved in terms of RSEI,and the average RSEI value of the ecological redline zones varied between 0.52 and 0.63,showing an overall fluctuating upward trend.(2)The year of the sudden change in the mean value of RSEI in the ecological redline zones as a whole was 2003,and the sudden change in the mean value of RSEI in ecological redline zones in each city was mostly concentrated between 1995 and 2005,with some cities in southern Jiangsu and central Jiangsu showing a sudden change from good to poor in the 1990s,and cities in northern Jiangsu showing a sudden change from poor to good in the 2000s.(3)The ecological redline presented a shielding effect in blocking the encroachment of impervious surfaces and bare soil,such as building land,into the protected area,with a significantly higher trend of RSEI growth within the ecological redline zone than outside.Among the 13 cities,Nantong,Suzhou,Wuxi,Changzhou,and Zhenjiang were the cities with significant improvement,Nanjing,Xuzhou,and Taizhou were the cities with accelerated improvement,Lianyungang and Huai'an were the cities with slow improvement,Suqian,Yangzhou and Yancheng were the cities with insignificant improvement of RSEI,the"red line"policy has no obvious effect on improving the ecological quality of the ecological redline zones in these three cities.This method can be used for the operational monitoring and assessment of the implementation effects of ecological redline policy.