黄河三角洲盐碱地水-肥-盐一体化综合调控机理与技术模式

In Yellow River Delta, coastal saline soil is widely distributed. Comprehensive management and use for these extremely rich reserve farmland resources has risen to national goal, becoming one of the central task of the local Agricultural High Tech Industries Demonstration Zone. Changeable environment has led to obvious change in soil water and salt dynamics in Yellow River Delta. Integration of water and fertilizer has become an inevitable choice for the sustainable development in this region, but the water-fertilizer-salt-crop interaction and regulation mechanism and its impact on ecological environment still need further study. Focusing on the soil water/fertilizer/salt dynamic rules, regulation mechanism, related ecological environment effects and other issues in the saline farmland of Yellow River Delta, this project will plan to investigate crop water and nutrient relationship and their quantitative relation under salt stress conditions, to clarify the effects of soil water/fertilizer/salt dynamics on crop growth and ecological environment and related regulation mechanism, to put forward feasible technical modes in farmland scale for soil water/fertilizer/salt management and regulation in order to improve water and nutrient use efficiency and prevent secondary salinization, and thus to provide reliable and scientific basis for integrated management and efficient use of the coastal saline land in Yellow River Delta and local agricultural sustainable development.

黄河三角洲滨海盐碱土分布集中、广泛，盐碱后备耕地资源极为丰富，其综合治理与高效利用已上升为国家目标，成为黄河三角洲农业高新技术产业示范区的中心任务之一。变化环境导致黄河三角洲的水盐动态和水土环境发生了明显改变，水肥一体化成为黄河三角洲农业可持续发展的必然选择，但有关水-肥-盐-作物之间的互作关系与调控机理及其对生态环境的影响仍有待进一步深入研究。针对黄河三角洲盐碱农田中的土壤水肥盐动态变化规律与调控机理及相关的生态环境效应等问题，本项目拟开展滨海盐碱地盐分胁迫条件下的作物水分、养分关系及其定量刻画研究，阐明水肥盐动态对作物生长和生态环境的影响及相关的调控机制，以提高水分、养分利用效率和防止土壤次生盐碱化为目标，提出适合当地农田尺度水肥盐管理与调控的技术模式，从而为黄河三角洲滨海盐碱地的综合治理与高效利用及当地农业可持续发展规划管理提供合理可靠的科学依据。

针对黄河三角洲淡水资源短缺、地下水埋深浅且波动大、土壤盐渍化严重且养分有效性低等问题，本项目围绕盐分胁迫条件下作物的需水耗水机理及其定量表征、盐分胁迫对作物养分吸收利用的影响及其定量表征、土壤水-肥-盐耦合过程及其对作物生长的影响与生态环境效应、农田灌水-控盐-施肥管理技术模式与优化等内容，开展了室内与田间试验、区域调研、数值模拟及理论分析等大量研究工作，圆满完成了既定目标，主要取得了如下几方面进展：.（1）系统考虑土壤-作物水分关系，揭示了盐碱农田作物需水耗水机理，改进了作物水分亏缺程度评估方法，阐明了智能灌水控盐机制，并依据黄河三角洲地下水埋深动态变化条件，提出了相应的土壤水盐调控技术。.（2）基于盐碱农田土壤-作物养分关系，阐明了作物养分（氮、磷）吸收利用机理与调控机制，并结合滨海盐碱土改良要求，因地制宜提出了合理可靠的养分资源高效利用与管理技术。.（3）基于水肥盐耦合机制，明晰了盐碱土改良对土壤水肥盐运移转化与作物生长的影响，改进了作物生长与水肥盐耦合运移模型，并在综合考虑水肥利用效率、经济效益与生态环境效应的基础上，提出了适合于黄河三角洲滨海农田的水肥盐一体化综合调控技术。.（4）利用遥感与地面监测相结合的方式，分析总结了黄河三角洲土壤盐渍化类型、分布与利用等演变动态，结合前述研究结果，综合考虑土壤水-肥-盐-作物之间的互作关系，建立了水-肥-盐一体化智能调控系统，据此可因地制宜制定黄河三角洲盐碱农田智能灌水-控盐-施肥优化技术模式。.相关研究成果可丰富土壤水盐运动理论，为黄河三角洲滨海盐碱地的综合治理与高效利用及当地农业可持续发展提供科学依据。