华北平原农田关键带分类研究

The critical zone of the Earth is an area where the atmosphere, hydrosphere, biosphere, lithosphere, and pedosphere interact and where material migration and transformation occur. It is also a crucial area that determines the survival and development of human society. Chinese scholars have classified the critical zone of the Earth according to differences in land use, among which the farmland critical zone is a type that is most strongly affected by human activities. However, existing research has considered more surface elements, with fewer elements related to the vadose zone and aquifer, and insufficient attention has been paid to the attributes of the underground part of the critical zone. As an important high-yield grain production area in China, the North China Plain has a serious problem of overexploitation of groundwater, and the risk of environmental pollution caused by agricultural production has increasingly attracted attention. Conducting research on the classification of the farmland critical zone can provide basic scientific support for the evolution and protection of groundwater quantity/quality in this area. This study comprehensively considered factors such as the characteristics of Quaternary sediments, the depth of shallow groundwater, the salinity of groundwater, and the types of agricultural land use in the North China Plain. Based on the principles of comprehensiveness and dominant factors, a three-level classification scheme for the farmland critical zone in the North China Plain was formulated. By using the overlay method to overlay and combine the classification factors, a classification scheme for the farmland critical zone in the North China Plain was proposed, dividing the North China Plain into 38 types of farmland critical zones. This study is of great significance for an in-depth understanding of the impact of agricultural activities on the groundwater environment.

地球关键带是大气圈、水圈、生物圈、岩石圈、土壤圈相互作用并发生物质迁移转化的区域,也是决定人类社会生存和发展的关键区域。我国学者根据土地利用的差异对地球关键带开展了分类,其中农田关键带是人类活动影响最为强烈的一类。但已有研究更多考虑的是地表要素,包含包气带和含水层方面的要素较少,对关键带地下部分的属性关注不够。华北平原作为我国重要粮食高产区,地下水超采严重,农业生产引起的环境污染风险日益引发关注。开展农田关键带分类研究可以为该区域地下水水量/水质演化及保护提供基础科学支撑。本研究综合考虑华北平原的第四纪沉积物特征、浅层地下水埋深、地下水矿化度以及农业土地利用类型等要素,在遵循综合性原则和主导因素原则的基础上,制定了华北平原农田关键带三级分类方案。通过使用叠置法对分类要素进行叠加和合并,提出了华北平原农田关键带的分类方案,将华北平原分为38个农田关键带类型。本研究对于深入认识农业活动对地下水环境的影响具有重要意义。