论文部分内容阅读
半个多世纪的研究查明,松嫩平原苏打盐渍土是环境要素综合作用的结果,而蒸发使地表水析盐和地下水上升地表积盐的耦合机制是主导成因。盐类以苏打为主,类型包括盐土、碱土及衍生的盐-碱化土。面积393.70万hm2,盐渍化过程还在持续。种稻排盐是改良苏打盐渍土的主要途径。古河道发现和试验示范为其大规模开发提供了可行性。大安等多个灌区建设具有强化粮食基地,优化环境和发展经济的综合效益,并成为东北地区第四大水稻区,使区域盐碱地开发形成完整格局。但是,这种盐碱地大规模开发存在使松花江和嫩江以及查干湖水体污染和土壤次生盐渍化的风险。在分析这些风险成因基础上,提出不向河湖直接排放稻田含盐碱尾水,并在查干湖外围建设湿地水处理系统的控制措施,防止对查干湖构成污染,采取将水田布置在古河道带等措施,控制旱田次生盐渍化。
More than half a century of research has identified that the sodar saline soil in the Songnen Plain is the result of a combination of environmental elements, and the coupling mechanism that causes surface salt precipitation and rising surface salt by groundwater is the dominant cause of evaporation. Soda-based salt, including salt, alkaline earth and salt derived - alkaline soil. An area of 393700 hm2, salinization process is still ongoing. Rice row salt is the main way to improve soda saline soil. Ancient river discovery and pilot demonstration provided the feasibility for its large-scale development. Da’an and other irrigation districts have the comprehensive benefits of strengthening food base, optimizing environment and developing economy, and become the fourth largest rice area in Northeast China, forming a complete pattern of development of saline-alkali land in the region. However, the large-scale development of this saline-alkali land places the risk of water pollution and soil secondary salinization in Songhua River, Nenjiang River and Chagan Lake. Based on the analysis of the causes of these risks, this paper puts forward the control measures of not discharging the saline-alkali water tailings directly to the rivers and lakes and constructing the wetland water treatment system in the periphery of the Chagan Lake so as to prevent the pollution of the Chagan Lake. Ancient river courses and other measures to control the secondary salinization of dry land.