Laboratory Simulation Studies On The Combination Of Pioneer Macrophyte Species Treating Eutrophic Water

Lake eutrophication is a serious worldwide ecological problems, it has also become more and more serious environmental problem along the middle and lower reaches of Yangtze River. Eutrophication bring knock-on effects in aquatic plants of main water ecological system primary producer on a large scale decline and vegetation succession. As a result of speeding up the aquatic ecosystem degradation, it is also leading to the instability of the system and the water quality deteriorated, resulting in a more serious ecological crisis. The existence and how much the abundance of aquatic plants have a direct and decisive influence on lake aquatic ecosystem structure and function. Therefore, this research mainly focused on shallow lake aquatic plant eutrophication technology development of the ecological restoration, determining the optimal aquatic plant ecological restoration for purification of combinatorial pioneer. The technology of exploration and development for the middle and lower reaches of Yangtze River plain shallow eutrophic lake ecological restoration will play a great role in promoting. For protection and management of the middle and lower Yangtze river plain, especially Jiangxi speckled with shallow lake wetlands provide scientific basis.The main content and results are as follows:(1) Aquatic macrophytes in water ecosystems, water maintaining benign operation is the key to the healthy operation of ecological groups. The use of aquatic plants for ecological restoration should first determine the optimal pioneer species of aquatic plants ecological restoration. This research take the Jiangxi local common aquatic plant species as the object of studying. Local ecological eehabilitation four pioneer species of aquatic plants of two life forms integrated filter out through literature review and field survey data. There are Ceratophyllum demersum and Myriophyllum spicatum of submergent plants, Typha angustifolia Presl and Acorus calamus L of emersed plant.(2) Submerged plants because of its fully aquatic features makes the most sensitive response to environmental stress in aquatic plant life form, their presence play a supporting role in the stability of the structure and function of the water ecosystems. Therefore, the submerged plants for ecological restoration of aquatic plant communities building plays a key role. Through the indoor artificial cultivation simulation experiments to study the different planting density sinking water removal capacity of the plant nutrients nitrogen and phosphorus, determining the optimum planting density of submerged plants is3g/L.(3) Portfolio construction techniques and aquatic plants mosaic eutrophic water purification effect through simulation experiments focus on aquatic plants, founding that the different life forms of aquatic plants plant reasonable mosaic formed by the combination of aquatic plant communities, the purification rate is higher than a single life form of aquatic plants and purification effect is more stability, strengthening the buffering capacity of water bodies to foreign pollution impact.(4) Determination of Myriophyllum spicatum+Typha angustifolia Presl mosaic combination for different life forms of aquatic plants in the optimal combination of mosaic test.