我国棉花主产区变化与地膜残留污染研究

Migration of cotton planting regions and residual pollution of mulch film in China

地膜覆盖是我国农业应用最为广泛的农艺技术之一,极大地促进了我国棉花产业的发展,推动了我国棉花主产区的变化。笔者采用实地调研和文献统计数据,对我国主要棉区地膜应用和残留污染特点进行大范围采样,获取第一手数据;同时,对过去几十年中与棉花地膜覆盖技术应用数据进行整理归纳,总结了我国棉花生产格局的变化特点,分析了地膜覆盖技术对我国棉花产业的影响,探讨了主要棉区农田土壤地膜残留污染特点和趋势。结果显示,我国棉花的主产区从过去的黄河和长江流域迁移到现在的西北内陆地区(主要是新疆),其种植面积占全国的70%。新疆等西北内陆地区自1986年开始规模化应用地膜覆盖技术后,棉花单产(皮棉)快速上升,现在已经超过2000 kg/hm2,大幅度超过长江和黄河流域的棉花单产。同时,新疆棉区地膜覆盖应用所带来的残留污染已成为该区域农业可持续发展面临的一个重大问题,新疆连续10 a和20 a覆膜的棉田土壤中残膜量分别为259.70±36.78 kg/hm2和307.90±35.84 kg/hm2。因此,地膜覆盖是我国棉花生产格局变化的主要驱动力之一,对保持我国棉花生产的稳定至关重要,但同时棉田地膜残留污染非常严重,必须尽快研究棉田地膜残留污染的应对策略,实现地膜残留污染的有效防控。

Plastic film mulching(PFM)is one of the most widely applied agricultural technology in China,which changes the distribution of cotton planting regions and greatly improves the development of cotton industry in China.Two methods including on-site investigations and literature and statistical data collection were used to conduct a large-scale sampling of the characteristics of mulch film application and residual pollution in main cotton areas in China to obtain first-hand data.At the same time,the application and data of cotton film mulching technology in the past few decades are sorted and summarized.The changing characteristics of cotton production pattern in China were reviewed.The effects of mulching technology on cotton industry in China were analyzed.The characteristics and trends of residual pollution of mulch film in the soil of main cotton farmland were discussed.The results showed that cotton yield increased sharply to today’s 2000 kg/hm2 in Xinjiang after wide application of PFM technology,which is much larger than that in the Yangtze or Yellow River Basin.Therefore,China’s main cotton planting area has migrated from previous Yangtze and Yellow River Basin to today’s Northwest inland region.However,residue accumulation of plastic film has become a serious problem and affects sustainable development of cotton industry.The residue accumulation of plastic film in the soil after 10 and 20 years of PFM application in Xinjiang was 259.7±36.78 kg/hm2 and 307.9±35.84 kg/hm2,respectively.Therefore,PFM technique will continue to play a key role in maintaining the stability of cotton production,and plastic film pollution will be more and more serious in the future.We must take some powerful actions to control residual pollution of plastic derived from PFM in China.