廊坊市植被覆盖度的变化对气候因子及人类活动的响应

Response of Variation of Vegetation Coverage to Climate Factors and Human Activities in Langfang City

【目的】探明廊坊市植被覆盖度的变化及其对气候因子的响应,为廊坊市林业生态环境建设相关政策的制定与应用提供参考。【方法】利用2000-2019年的MODIS/NDVI数据,采用像元二分模型、趋势分析和相关分析方法,研究廊坊市植被覆盖度的变化及其对气候因子的响应,并通过残差分析探讨人类活动对植被覆盖的影响。【结果】2000-2019年廊坊市年平均植被覆盖度整体上呈波动上升趋势,2008年植被覆盖度达最大,为35.23%,2000年最小,为26.94%,平均为32.20%,其中安次区、广阳区、永清县和固安县植被覆盖改善最明显;植被覆盖度与气温呈弱的正相关关系,与降水呈显著的正相关关系;在残差变化趋势中,总面积63.1%的区域残差为正,大于残差为负的区域面积比例,人类活动对植被覆盖具有改善作用,廊坊地区的三北防护林建设工程和创建森林城市工程的实施,对全市植被覆盖提高具有促进作用。【结论】降水对廊坊市的植被生长起着关键性作用,人类活动对植被覆盖具有改善作用,廊坊地区的三北防护林建设工程和创建森林城市活动对全市植被覆盖的提高具有促进作用。

【Objective】The variation of vegetation coverage and its response to climate factors are discussed to provide a reference for formulation and application of relative policies about forestry ecological environment construction in Langfang.【Method】The variation of vegetation coverage and its response to climate factors are analyzed by using the dimidiate pixel model,trend analysis and correlation analysis based on MODIS/NDVI data and the effect of human activity on vegetation coverage is analyzed by the residual analysis.【Result】The average annual vegetation coverage with an average of 32.20%shows a fluctuation rising trend in Langfang from 2000 to 2019 overall.The vegetation coverage reaches the maximum(35.23%)in 2008 and the minimum(26.945)in 2000.The vegetation coverage in Anci District,Guangyang District,Yongqing County and Gu’an County is obviously improved.There is a weak positive correlation between vegetation coverage and temperature,and a significant positive correlation between vegetation coverage and precipitation.The residual of 63.1%area of total area is the positive,which is more than the area proportion of the area with a negative residual.The human activity has the improvement effect on vegetation coverage.The implement of the Tree-North Forest Shelterbelt Program and forest urban engineering have the promotion effects on increase of vegetation coverage in Langfang.【Conclusion】The precipitation has the key effect on vegetation growth.The human activity has the improvement effect on vegetation coverage.The implement of the Tree-North Forest Shelterbelt Program and forest urban engineering have the promotion effects on increase of vegetation coverage in Langfang.