基于人工湿地的复合池塘养殖系统模型化研究

In recent years, there has been increasing popular problems related to environmental pollution, resource waste and product quality and safety across the industry of pond aquaculture. These problems have strictly restrained the sustainable development of pond aquaculture and therefore the need to upgrade the traditional culture model integrated with new technology is becoming essential. As a low-cost waste water treatment facility, constructed wetland (CW) has been gradually utilized in aquaculture. In comparison with other water treatment facilities, CW comprehensively uses the biological and solar energy in nature, hence possessing the advantages of low cost for construction, low energy consumption, high purifying performance and easy management. The integration of CW to pond aquaculture not only saves water resources by realizing zero discharge of aquaculture waste water, but also guarantees the quality and quantity of aquatic products via improving the eoc-environment of culture pond. However, studies on the application of CW to pond aquaculture are still in a qualitative stage, lack of systemic and quantitative investigations. The following project for application is concerned about a compound system consisting of CW and culture pond, aiming at revealing the dynamic process and mechanisms of aquaculture effluent purification by CW via a series of pilot-scale experiments. In the meantime, it is likely to propose the appropriate configuration parameters and best management scenarios for the compound system based on the coupling of models for wetland purification, pond water quality dynamics and fish growth. The final goal is to provide technical support for the improvement and application of the compound system in the near future.

近年来，池塘养殖业中普遍存在的环境污染、资源浪费、质量安全等问题日益突出，这些已严重制约了池塘养殖业的可持续发展，迫切需要整合其他技术来实现池塘养殖模式升级。人工湿地作为一种低成本的水处理设施，已被应用于水产养殖尾水处理。相比于其他渔业废水处理，人工湿地综合利用了生物能和天然能，具有构建成本低，能耗少，运行效果好，便于维护等优点。将人工湿地整合到池塘养殖，不仅实现了养殖废水的零排放，节约了水资源，同时也改善了池塘生态环境，保障了水产品的质与量。然而将人工湿地应用于池塘养殖进行水循环还处于定性阶段，缺乏定量研究。本次拟申请项目以人工湿地-池塘复合系统为对象，旨在通过系列试验揭示人工湿地净化养殖废水的动态过程与机理，同时在耦合湿地净化模型，池塘水质动态模型和鱼类生长模型基础上，提出系统适宜的配置参数和最佳的运作管理模式，从而为该复合模式的改进和推广应用提供技术支撑。

在面临全国水污染形势日趋严峻的局面下，探究适宜的水处理设施解决和控制好水产养殖废水排放，增加水体循环使用力度，是实现水产养殖可持续发展的重要途径。人工湿地作为一种低成本的污水处理技术，现已被逐渐应用到水产养殖。本项目针对人工湿地-池塘组成的复合系统，从复合系统的构成要素着手，重点开展了以下几方面研究：1）探讨了不同要素组成与运行工况组合下潜流湿地的净化效果，发现①无论曝气与否，垂直流湿地系统内部都存在明显的硝化过程。人工曝气进一步强化了湿地内部的矿化和硝化过程。②渍水状态下垂直流湿地对氨氮的去除效果较弱，对亚硝氮的去除率较高；缺水状态下垂直流湿地对氨氮的去除率较高，对硝态氮的去除率均呈负值。③人工曝气显著提高了下行+上行+水平流组合湿地对有机物、氨氮、亚硝氮和总磷的净化效率。④针对三级水平流+表面流组合系统，有机物、氮磷在各级湿地中呈逐级降低趋势，且有机物、氮磷的去除主要发生于一级湿地。2）构建了不同要素组成垂直流湿地渍水与缺水状态下净化养殖废水的动力学模型，首次提出了去除率常数受控于多元因素共同制约的线性假设，并用Stella仿真软件对构建的9组垂直流湿地系统进行了动态模拟。3）建立了复合系统中养殖池塘溶解氧和氨氮的水质模型。4）探讨了复合系统中池塘水质变化与养殖效果的分布特征。5）确立了复合系统的面积配比，通过关系演算，得出湿地-池塘的面积配比约为0.1。以上这些研究为人工湿地在水产养殖业中的应用提供了技术支撑。通过上述研究已经发表论文7篇，其中SCI论文4篇，EI 4篇（2篇同时被SCI、EI检索），申请国家发明专利5项（已经授权3项），获成果奖2项，培养了硕士研究生3名。