2000—2019年中国农业塑料污染的时空变化评估

Assessment on Spatiotemporal Changes of Agricultural Plastic Pollution in China from 2000 to 2019

农业塑料污染产生严重的生态环境问题,但农业塑料的空间分布格局及其时序变化的影响因素缺乏精细化的评估与归因。基于一种可用的指数模型,本文反演评估我国2000—2019年以塑料薄膜、化肥袋与农药瓶为主的农业塑料污染源的时空变化特征,并筛选9种关键的社会-生态影响指标,结合最小二乘法、地理加权模型与随机森林方法,对农业塑料废弃物变化进行整体-局部尺度的归因分析。结果发现,全国上述农业塑料数量呈现增加-平稳-下降的变化趋势,其空间聚集性和区域差异性在研究期内逐步减弱。影响整体农业塑料污染的因子按重要性由大到小排序为:农业机械总动力、降水、粮食作物播种面积、第一产业增加值、日照时数、国内专利申请受理量和乡村人口。局部尺度农业塑料污染的影响因子系数与整体尺度的因子空间分布特征类似,但其空间聚集特征随时间变化明显减弱。研究结果对实施农业塑料污染的动态监测、影响评价与防控策略等具有科学参考价值,可以提供数据支持。

Agricultural plastic pollution causes serious ecological and environmental problems,but the spatial distribution pattern of agricultural plastics and the influencing factors of their temporal changes lack refined evaluation and attribution.Based on an available index model,the spatiotemporal variation characteristics of agricultural plastic pollution sources in China are inverted and evaluated in this paper,mainly plastic films,fertilizer bags,and pesticide bottles,from 2000 to 2019,and nine key social-ecological impact indicators are selected,and combined with the least squares method,geographic weighted model,and random forest method,a global-local scale attribution analysis is conducted on the changes in agricultural plastic waste.The results show that the quantity of agricultural plastics mentioned above in China shows a trend of increasing-stabilizing-decreasing,with its spatial clustering and regional differences gradually weakening during the research period.The factors that affect overall agricultural plastic pollution are ranked in descending order of importance:total power of agricultural machinery,precipitation,sowing area of grain crops,added value of primary industry,sunshine hours,domestic patent application acceptance,and rural population.The impact factor coefficients of local scale agricultural plastic pollution are similar to the spatial distribution characteristics of overall scale factors,but their spatial clustering characteristics significantly weaken over time.The research results have scientific reference value for implementing dynamic monitoring,impact assessment,and prevention and control strategies of agricultural plastic pollution,and can provide data support.