国道网路域森林覆盖时空变化及驱动力分析

基于2000—2017年森林变化数据集、气象数据和社会经济数据,采用邻域分析、统计分析和多元逻辑回归分析对我国国道网路域森林植被变化特征及其驱动力机制进行了系统地分析。结果表明:空间上,我国国道路域森林覆盖具有显著的随着与道路距离增大逐渐减小的净丧失的梯度变化特征,国道的影响域为道路两侧0~2700 m范围,具体表现为:恢复率、丧失率和总变化率在影响域内随距离增大而增大,在影响域外随距离增大而减小,净丧失率在影响域内、外均随距离增大而减小;国道影响域森林丧失率有明显的省市自治区分区差异特点,华东和华南地区高于全国平均,华北、华中、西南、西北和东北地区低于全国平均;同属一个分区的不同省份国道影响域森林丧失率高低也有较大差异,各省份国道影响域森林丧失率梯度变化规律显著性程度不同。时间上,近17 a,我国国道影响域森林丧失总体呈波动上升趋势,尤其在2015年后丧失率出现较大增长;而华北、华中、东北地区国道影响域森林丧失率在2008年后出现逐年波动下降趋势。气象水文条件和本底森林覆盖度是造成国道影响域森林丧失差异的主要原因,地形地理、气象水文、人类活动等因素对国道影响域森林丧失影响的协同作用与距离因素无明显相关性。

Analysis of the spatiotemporal changes and driving forces of forest coverage in the national highway network domain,China

Based on the 2000-2017 forest change,meteorological,and socioeconomic datasets,the characteristics of forest vegetation change and its driving mechanisms in the national highway network area of China,were system atically analyzed using neighborhood,statistical,and multivariate logistic regression analyses.The results show that spatially,the forest cover of the national road area in China has exhibited a substantial gradient of net loss,which gradually decreases with an increase indistance from the road.The effective zones of the national road was in the range of 0-2700 m on both sides of the road.The forest recovery rate,loss rate,and total change rate increased with an increase in distance within the effective zones,and decreased with an increase in distance outside of the effective zones.Net loss rate decreased with an increase in distance inside and outside of the effective zones,and the forest loss rate of the national highway effective zones displayed significant characteristics between different provinces,municipalities,and autonomous regions.The forest loss rates of East and South China were found to be higher than the national average,and the forests in the North,Central,Southwest,Northwest,and Northeast regions were lower than the national average;forests in different provinces in the same area were all affected by national highways.There were also large differences in loss rates as well as in the degree of significance of the gradient change in the forest loss rate in the effective zones of the national highways in each province.From a temporal perspective,the overall loss of forests in the effective zones of China′s national highways showed a fluctuating upward trend,with loss rate showing a rapid increase after 2015.The loss rate of forests in the areas affected by the presence of national highways showed a fluctuating decrease after 2008 in North,Central and Northeast China.Meteorological and hydrological conditions and background forest coverage were the primary factors contributing to the differences in forest loss across the national highway effective zones.The synergy of topography,geography,meteorology,and hydrology,human activities,and other factors on forest loss around national highways had no significant correlation with distance factors.