This study takes Shannan City in Tibet as the research object, and proposes peak paths and specific policy suggestions based on the prediction results of carbon emission peak values in different scenarios by constructing a GM-ImPACT model. The results show that, the current economic growth rate coupled with strong emission reduction strategies is the optimal path for Shannan City to achieve carbon peak. Shannan City is expected to achieve carbon peak 10 years ahead of schedule in 2024, reducing its total carbon emissions by 20.72%, and its carbon emission intensity will drop by 7.89 percentage points higher than the national level. The proposed model framework could be applied to explore the optimal path of carbon peak for other cities.

The Huangshui River Basin in Qinghai Province was selected as the research case. Considering the close relationship between climate change and hydrological cycle of the basin and the severe impact on the water environment system, the evaluation method system of water environment carrying capacity of the basin under the impact of climate change was constructed. The matching of time and space scales was carried out from the perspective of systematicness and integrity, so as to accurately evaluate the impact of climate change on the hydrological cycle of the basin scale and carry out the calculation of water environment carrying capacity. Finally, the assessment and analysis of the dynamic change of the basin water environmental carrying capacity under the influence of climate change was established. The research results show that climate warming would lead to a decline in the water environmental carrying capacity of the Huangshui River Basin, but with the passage of time, the water environmental carrying capacity under the future climate change scenario would generally improve.

Combined with the work of “Three Lines One Permit” in China, this study constructed a corresponding index system, and selected Qingpu District of Shanghai as the case study area to evaluate the consistency of regional ecological carrying capacity and industrial layout by both single factor and comprehensive index methods. The results show that: 1) the single factor ecological carrying rate can reflect the key limiting factors, while the comprehensive index can directly show the cumulative impact of regional industries on ecological carrying capacity; 2) the conflict between industrial layout and ecological space and soil environmental quality is less in Qingpu District, but the contradiction between industrial layout and water, atmospheric environment is prominent, which results in the overload of ecological environment and the disharmony between ecological carrying capacity and industrial layout; 3) the regions with prominent consistency problems are basically the same as the key units of environmental control, indicating that the index system is objective and feasible, can provide reference for relevant evaluation and research work, and has the feasibility of nationwide promotion. It is suggested to strengthen pollutant emission control for the key control units. 

The Dianchi watershed Basin was selected as a typical watershed. Considering the differences of regional natural geography, hydrometeorology and human activities, using 1 km×1 km grid data, the detailed simulation calculation of the pollutants entering the water source of agricultural sources is carried out. The rainfall driving factors, terrain driving factors, surface runoff factor, underground storage/groundwater runoff factor and interception factor are obtained. The average comprehensive water inflow coefficients of TN and TP from agricultural sources in Dianchi Basin in 2016 are 0.447 and 0.342 respectively, and the actual water inflow loads of TN and TP from agricultural sources in 2016 are 577.39 t and 167.62 t respectively. The results show that the discharge of agricultural source pollutants and the load of influent water have significant spatial variation in Dianchi Lake Basin. 81.0% of nitrogen and 74.2% of phosphorus were concentrated in Caohai land area and the north coast of the open sea. The largest emission was in the upper reaches of Panlong River, with nitrogen and phosphorus accounting for 21.9% and 20.2% respectively. It is also found that livestock and poultry breeding account for more than 90% of the total TN and TP emissions of from agricultural sources, which should be the focus of agricultural source pollution control. 

Based on the spatial grid of the kilometer scale, the basic evaluation unit is constructed. The consistency evaluation of regional ecological carrying capacity and industrial layout are carried out. The Qingpu District of Shanghai is used as a research case. The results show that proposed method can effectively identify the regional ecological carrying capacity and the spatial distribution of industrial pressure, and evaluate the consistency of the regional ecological carrying capacity and industrial layout. The average industrial pressure index of Qingpu District is 0.51, and the ecological carrying capacity index is 0.25. The ecological carrying capacity of Qingpu district has a high consistency with the industrial layout, and the average consistency index is 3.12.