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The scientific management of ecosystems is key to the sustainable development of ecosystems. Owing to their limitations, traditional management methods can no longer solve the complex problems encountered in ecosystem management. An emerging management method, namely adaptive management, has received wide attention from scholars. The quantitative characteristics of domestic and foreign studies on ecosystem adaptive management from 2010 to 2020 were examined by literature analysis and comparative analysis. The connotation development, type, and application conditions of adaptive management were classified. The main research direction of ecosystem adaptive management was summarized. The existing problems of current ecosystem adaptive management research were identified, and corresponding countermeasures and suggestions were proposed. The specific conclusions can be summarized as follows:The research direction of ecosystem adaptive management and the development trend of the number of documents are almost the same in China and abroad, but there is a large gap in the quantity of literature. The connotation of adaptive management has continually improved, but the application of ecosystem adaptive management still has limitations. Therefore, it is urgent to reach a unified understanding of the connotation and expand the application scope to take full advantage of adaptive management, promote sustainable ecosystem development, and achieve the best ecological, economic, and social benefits.

Based on analysis of land-use data from Chaobai River region in 2001, 2005, 2009, 2013, and 2017, land-use change and the dynamic evolution of ecosystem services during different periods have been illustrated in this paper. A land-use dynamic attitude model, the equivalent factor method, and the sensitivity index method were used in this study. The results obtained:During the period of 2001-2017, the area covered by arable land and rural settlements in this region decreased significantly, while the proportion of urban land and water-cover increased gradually. The main types of land use in this region were arable land, rural settlement, and urban land. In addition, the specific gravity of the arable land and rural settlements reduced gradually, while that of urban land increased gradually. The dynamic degree of urban, industrial, and mining lands, as well as that of water-cover, increased greatly, while it reduced greatly for rural settlements, arable land, pasture, and forest. In the past 20 years, the ecosystem service value (ESV) of the region had been increasing, where the increase in the ESV of water-cover played a decisive role. From 2001 to 2017, the sensitivity index of all kinds of land in this region had been less than 1. The sensitivity index decreased in the order of arable land > water area > forest > pasture. In conclusion, according to information on the effect of land-use change on ecosystem services in this region, it is necessary to formulate proper policies and build a rational land-use pattern to improve ecosystem services.

Secondary water supply, as the final component of the urban water supply system, is critical for ensuring the safety of urban water supply, and is directly related to customers’ water use. However, water stored in secondary water supply facilities will more likely to lose disinfectants (chlorine residual) which can lead to bacterial regrowth and water quality deterioration. Therefore, it is important to solve problems associated with secondary water supply and manage the system more effectively. In the context of the Internet of Things, the intelligent management model based on information technology has become the growing trend. This paper introduces the application of the secondary water supply intelligent management model in Shanghai.

In this study, the microbial ectopic fermentation bed filler was taken as the research object to study the effects of different raw materials on the treatment effect of pig breeding wastes. Under the same conditions, the effects of corn stalk filler and the mixture of rice husk and coconut shell powder on temperature, pH, moisture content, microbial population and nutrient content were analyzed. The results showed that the mixture of rice hulls and coconut husk was easier to control temperature changes, maintaining at 25~54℃. At the same time, its pH change was small, at 7.6~8.9, closer to the optimum pH for aerobic fermentation range. The moisture content of the rice husk and coconut husk mixture filler was slightly lower than that of the corn stalk filler, maintaining between 44%~64%. At the end of the experiment, all the indexes of the two kinds of fermentation bed accorded with the national standard of organic fertilizer.

In order to provide theoretical basis for application of the ectopic microbial fermentation bed, the efficiency and quality of the ectopic microbial fermentation bed in processing piggery waste were evaluated by measuring the changes of physicochemical and environmental factors and the absorption of piggery wastewater. The results showed that the fermentation temperature of the filler maintained above 40℃ for up to 48 days and the highest fermentation temperature was 66℃. The alkaline environment and the moisture of filler remaining 50%~65% during the fermentation was suitable for aerobic fermentation of microorganisms. The absorption coeffient of piggery wastewater of the filler was 2.53, which was better than that of dairy wastewater. Microbial activity was mainly based on bacteria in the fermentation system and the organic matter was degraded and utilized by microorganisms at the same time. After the fermentation, the total nutrient content and the organic matter mass fraction of the filler was 6.19% and 56.11%, respectively, which met with the national standard for organic fertilizer.

The construction of bridges across rivers mostly involves occupying river sections and dike sections, which will adversely affect flood control of rivers and the safety and stability of dikes. Taking an actual project for example, this paper puts forward some ideas and methods for the analysis of impacts of crossing bridges on flood control and dike safety, analyses and evaluates effects of raising of water level, dike foot erosion, seepage stability and anti-sliding stability. Finally, suggestions and measures for bridge construction and dike protection are raised.

The staging simulation model is based on the flood season staging, which considering the weather system genesis and rainstorm characteristics. Moreover, the physical mechanism of rainfall runoff can be comprehensively considered, and the physical meaning of the parameter can be better reflected in different stages. In this paper, the Tingxia basins in the humid and semi-humid areas are selected, which the flood season can be divided into in plum rains period and the typhoon period, then the staged simulation model is constructed by the staged rate. Some statistical indicators are introduced to evaluate the effectiveness of the staging rainfall-runoff model in improving simulation accuracy, the simulation results are ideal, and the accuracy is improved.