Review of Restoration Technology and Multi-environmental Factors Analysis of West Lake Ecosystem in Hangzhou City

The urban lake ecosystem has the characteristics of long-term,complex and comprehensive in its ecological restoration process because it is related to social and economic activities at multiple levels.Located in Hangzhou City,China,the West Lake is a national-level scenic spot and a world heritage cultural landscape.It provides key ecosystem services for the city and has a significant impact on the urban ecological environment and the well-being of citizens.The West Lake has undergone an 1800-year governance process in history,realizing the harmonious coexistence with Hangzhou City.Since modern times,due to the rapid development of urbanization and industrialization,the water quality of the West Lake and its freshwater ecosystem have been greatly damaged.Since 2002,Hangzhou City has achieved the overall restoration of the West Lake ecosystem through a series of measures,such as water diversion projects,dredging projects,and the West Lake comprehensive protection project,and the water environment and lakeshore landscape have been greatly improved.This study analyzed the restoration technology of the West Lake ecosystem from two scales of the watershed and the site and discussed the water ecological governance system of the West Lake in the past 20 years.Through thedata analyses of the West Lake land use,vegetation,TP,TN,NH_(3)-N,COD_(Mn) and other multi-environmental factors,the results showed that the water quality,transparency and eutrophication of the West Lake had been greatly improved.At the same time,the application of large-scale restoration methods and technologies also required long-term observation,and attention should be paid to the proliferation of alien species and the loss of heritage value,so as to further avoid potential ecological risks caused by ecological restoration.

Simulation Environments: Challenges for Advancement

A brief review of the basic terminology on simulation, simulation life-cycle activities such as model-based activities, behavior-oriented activities, and quality assurance activities is given. Then, the challenges and opportunities for the advancement of the state-of-the-art in simulation environments are discussed under the following headings: modelling environments, simulation environments, mixed simulation environments, and comprehensive simulation environments.

Analysis on areal relationship between regional environment and socioeconomy—taking the Chinese Yellow Sea coastal zone as a case

From the regional view, this paper analyzes the regional difference between the environmental regional structure and the socio-economic structure, establishes the regional connection between them, and determines the leading direction of the regulation of the socio-economy to improve the environmental quality in different regions.

Comprehensive evaluation of heavy metal contamination of sediment in Lake Dianchi by using modified AHP method and ^(137)Cs dating

Through the use of general sampling and measurement by ^(137)Cs dating,problems regarding the absence of monitoring data can easily be resolved.Further,weighted values need to be determined while Environment Quality Comprehensive Index(EQCI)is commonly used as applied in environmental quality comprehensive evaluation.In order to overcome the subjectivity in determining weights,the modified Analytical Hierarchy Process(AHP)method was designed.The modified AHP method involved the following key procedures:First,the parameters y_(i1) and y_(i2) were calculated based on the monitoring data;second,the factors were put in order according to the symbol and value of y_(i1) and y_(i2);third,the continuous odd integers,which represented the importance of factors,were given to factors according to their seating order;and,fourth,the factor weights were determined from the pair-wise comparison matrix calculated by the ratio of the given odd integers.Therefore,the weights were completely based on the monitoring data.In the present study,the comprehensive quality of sediments in five sections of Lake Dianchi were evaluated and the results indicated that the current contamination of sediments in each lake section is much more serious than at any other time in history.