| From the 20th century, because of the fast increasing of human population, the demand of people with developing land is increasing accordingly, and consequently this development of land use with predatory exploitation and environmental problems caused by industry pollution has brought many disaster problems and instability to the wetlands, now wetlands becomes one of the most degraded ecosystems. In order to relieve the deterioration of the human living environment and the decrease of biodiversity, wetland restoration is being carried out as an important compensation method for wetland protection. Wetland restoration is to repair and reconstruct the degraded or disappeared wetlands by using biological, ecological techniques and ecological engineering methods. By now, many countries have begun researches on the theology and methodology of wetland restoration, but studies that combining the environmental, biological and social factors to evaluate and summarize the restoration effect and restoration techniques are still a shortcoming.Dianshan Lake region is an important water source in the upstream of the Huangpu River, providing many ecological functions like water conservation, water purification, land resource reservation, biodiversity conservation and so on. In order to relieve the environmental problems here, and put the water resource protection plan in this area into effect, a wetland restoration pilot project was carried out centering on Dalian Lakeside area, and some scientific studies concerning about the restoration of ecological environment and the protection of biodiversity were also developed in the same time. From August 2008 to Match 2010, parameters including land use pattern, vegetation, bird populations, amphibian populations, reptile communities, water quality and some social parameters were collected in the restoration area to assess the effects of the project; water quality and amphibian population were chosen as two important factors that affect the wetland environment and biodiversity to find out the key factors that affect the water quality and amphibians population, and then some restoration techniques and strategies concerning about wetland environment and biodiversity protection were put forward. The current situation of degraded Dalian Lakeside wetlands is also very typical around the Taihu Lake basin, so the development of the restoration project will offer scientific support and typical demonstration for the development of wetland restoration in Dianshan Lake and Taihu Lake basin.The study results were as follows:1)During the restoration period, this demonstration area which was dominated by intensive fish ponds (50%) and woods (25%) was reformed into a much more complicated landscape with open water (30%), multi-vegetation communities (50%) and with no fish ponds left anymore. A diverse ecological area which was characterized by vegetation succession with forest, shrub, herbaceous plants and aquatic plants was established instead of small fragmentation of patch woods before the project. This human-controlled fish pond wetland changed into a semi-nature wetland, also the change of the ecological foundation is good for the biodiversity conservation.2) On the part of bird population,11 orders,27 families and totally 65 species were recorded before the pilot project; 1 year later llorders,32 families and totally 71species were recorded, and also 11 species of water birds,10 species of terrestrial birds were newly found in this area; The total number of species and individual in the bird communities showed increase although not significantly (P>0.05), eleven new species were recorded after project, the Shannon-Wiener index (H') and Pielou index (J) also showed a significant increase after restoration, the total number and species of the targeted species-Geese and Ducks got a significant increase (6 species new recorded), also two species of Raptors were newly recorded and new distribution bird-Halcyon smyrnensis was found here after the project. In a word, the habitats and vegetation distribution can give a positive impact on the conservation of bird community.3) On the part of amphibians and reptiles, after the pilot project, two families three genera five species and totally 902 individuals of amphibians were recorded, significantly higher than 558 individuals before project, also the number of each kind of amphibians after the project were higher than that of before project; totally 3 families 7species of reptiles were recorded, and the individuals after the project was higher than that of before project.4)Based on the analysis of water quality parameters, after project, the content of chl.a, TN, NH4+,NO3-, TP, COD, DO significantly lower than that of before project(p< 0.05). That means after the project, the pollution sources has been a certain control and the density of organics decreased significantly.5) According to the characters of Dalian Lake wetland ecosystem, a set of ecosystem health assessment has been developed. In 2008, the structure health index, function health index and comprehensive health index were respectively 9.75,1.7 and 11.45, and in 2010 these three index were 14.26,9.25 and 23.51 correspondingly. In 2008 the health level of this area was in a very bad condition, and due to the implementation of the repair measures in 2010, the health of the ecosystem improved a lot, but still not in a best condition; as the stress of human activity(pressure index in 2010 was 21.34) decreasing gradually and the improvement of management and regulations from the government(response index in 2010 was 18.4), the functions of Dalian Lakeside wetland will become more effective. 6) By analyzing the key factors that affect the water quality, some details are as follows:the content of chl.a and COD showed a significant positive correlation with Tp instead of TN, so Tp was the most important limiting factor in this area. From this point, waste water from residential area, industry area and agriculture region should be controlled to prevent organics with P element entering into the water directly; also the bottom sediment played a very important role in the purification of water quality, so the depth of sediment should be controlled appropriately to reduce the release of organics; aquatic plants were also a factor that affected the balance between N, P.7) By analyzing the habitat selection patterns of amphibian population in Dalian Lake wetland, some detailed results are as follows:the numbers of species and individuals were lower in the constructed wetlands than that in the natural wetland; factor of human disturbance showed a negative correlation with the distribution of Rana limnocharis, R. nigromaculata and Microhyla ormata; and the numbers of Bufo gargarizans positively correlated with proportion of barren (P<0.05) compared with other variables; Rana limnocharis and Rana limnocharis preferred the more complicated habitats, proportion of water area, proportion of vegetation impacted on the number of R. plancyi positively (P<0.05); in addition, the capture of human was also an important reason for the decrease of R. nigromaculata population.
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