Study On The Recovery Effect Of Different Restoration Methods Of Degraded Wetlands In The Middle Reaches Of The Heihe River

Wetland is a unique ecosystem formed by water-land interaction on the earth.It is an important part of natural landscape and plays an important role in protecting biodiversity,storing carbon and nitrogen,providing diverse habitats,and maintaining regional ecological security.Due to the dual effects of natural factors and human activities,the wetlands in the middle reaches of the Heihe River have been degraded,seriously threatening the ecological security of the entire region.In order to maintain the ecological balance in the middle reaches of the Heihe River and even in the arid regions of the northwest,wetland restoration and protection have been carried out in the Heihe River Basin since 2006.The restoration and protection of wetlands can effectively offset the effects of degraded or even disappeared wetlands,but the effectiveness of the restoration? Which recovery method is more suitable for arid inland river wetlands? These issues are issues of common concern to governments,scholars,and local residents at all levels.Therefore,the study on the restoration effect of wetland under different restoration modes in the middle reaches of the Heihe River will help to summarize the recovery mechanism of the wetlands in the middle reaches of the Heihe River and select suitable wetland restoration methods to provide theoretical support for the successful restoration of the degraded Heihe wetland in the future.At the same time,it can also provide reference for the recovery of similar wetlands in arid areas.Based on the vegetation data obtained from field surveys and the soil data obtained from soil experiments,this paper compares the restoration effects of wetlands with replanting and watercourse restoration method,watercourse restoration method and natural restoration method.The plant diversity index,soil quality index,flora quality assessment index(FQAI),wetland flora evaluation index(FAQWet)and other Pearson product-moment correlation coefficient and one-way ANOVA were used to study the different wetlands in the middle reaches of the Heihe River.The restoration effect of the plants under the recovery mode;the restoration effect of the soil under different restoration modes in the middle reaches of the Heihe River;and the restoration effect of the wetland ecological quality under different restoration methods of the middle reaches of the Heihe River,and finally determine the best wetland restoration method.The main findings show that:(1)Through the restoration of wetlands,the number of species in the wetland restoration area in the middle reaches of the Heihe River increased.Some people who participated in the wetland restoration method were superior to the natural recovery method in terms of plant restoration performance,but the intensity of human participation was different,and the recovery effect was also significantly different.The diversity index,richness index and evenness index of the Watercourse restoration method were significantly higher than other recovery methods(P<0.05),indicating that the method is helpful for plant diversity maintenance;the replanting and watercourse restoration method wetland plant coverage The height was significantly higher than the other two recovery methods(P<0.05);the wetland plants in the water diversion type were significantly higher than the other two restoration methods(P<0.05).The promotion of plant growth in the process of wetland restoration is reflected in the overall improvement.It also shows that proper man-made management may become an effective means to promote vegetation restoration in the wetland restoration process in arid areas.(2)The soil moisture content of replanting and watercourse restoration wetland is the highest,soil bulk density and pH value are the lowest,and the water content of wetland is the lowest.The content of organic carbon and total nitrogen in various layers of soil showed the trend of replanting and watercourse restoration method > watercourse restoration method >natural restoration method.It reflects that proper man-made management during wetland restoration can effectively improve soil texture and increase soil nutrient content.Natural restoration method the soil available nitrogen content in each layer of wetland was the highest,and the total phosphorus and available phosphorus content in each layer were significantly higher than other recovery methods(P<0.05).It reflects that the natural recovery method may become an effective means for soil phosphorus sequestration in arid regions.(3)Through the comparative analysis of the wetland ecological quality evaluation index,the watercourse restoration method ecological quality is the highest.It shows that the wetland restoration under the watercourse restoration method is the best,and it also shows that the wetland water diversion irrigation in the arid area is an effective means to improve the effectiveness of wetland restoration.Wetland ecological quality assessment and specific environmental factors have their advantages and disadvantages in evaluating wetland restoration effects.Combining the two methods,we can accurately analyze the recovery performance of wetlands under different wetland restoration methods.(4)The watercourse restoration method method is feasible and effective in arid areas,but it is necessary to consider the shortage of water resources in the arid area and how to balance production and living with wetland restoration.In the process of wetland restoration,a stepwise recovery method can be adopted,which not only relieves the pressure of water resources but also ensures the recovery of wetland.