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• Maximising conservation benefits on state-owned land. • Quantifying land costs, ecological values and human values in an integrated climate context. • Adaptation of model parameters to research sites based on machine learning. • Ecological corridors avoiding the objective fragmentation of the Marxan model results. • Phased implementation of conservation plans. In China, especially in countries with state-owned land use rights, the loss of urban bird diversity due to rapid urbanisation can't be contained or ameliorated by equitably weighing the ecological and economic values of land. Climate change could further threaten urban bird biodiversity and ultimately lead to a "tragedy of the commons". The Beijing Ecological Cultivation Area (BECA) is one such area that has suffered from low eco-efficiency due to climate change and chaotic management. There is a need to find more effective solutions for urban bird conservation to reduce the negative impacts of rapid urbanisation while avoiding wasting more conservation costs. For this purpose, the protection priorities for BECA based on 4 global future climate models (RCP2.6, RCP4.5, RCP6.0 and RCP8.5) for the years 2041–2060, 56 species of local resident birds in the "Beijing Terrestrial Wildlife - Birds" were used as study subjects, which were identified through systematic conservation planning (scp) with combinatorial modelling (MaxEnt-Marxan). In addition, three scenarios were innovatively developed in Marxan with maximum respect for the original land use types. The eco-efficiency and eco-corridor of these three scenarios were compared and identified through ArcGis. The results of the survey show that 'Comprehensive Conservation' has the largest mean distribution area, with the results for RCP 2.6–8.5 being: 52.34%; 65.25%; 48.34%; and 45.42%. It had the highest spatial continuity, the lowest fragmentation, and the highest conservation efficiency. Moreover, We recommend a phased implementation of the conservation plans and and suggest planning options for three landform types: High-altitude mountain; Medium or Low-altitude shallow mountainous; and Water conservation areas. It is important to establish ecological corridors from the Huairou district's northern part to the Yanqing district's northeastern part and beyond. This paper quantifies the land costs, ecological values and human impact factors of the planning area in a comprehensive climate context with the theme of conserving urban bird diversity. This study aims to maximise the conservation benefits of urban bird diversity and to provide basic research for ecological conservation on state-owned land. [ABSTRACT FROM AUTHOR]

• A water optical classification method was developed using density peaks. • The class-specific retrieval models of surface water turbidity were established. • Long-term dynamics of surface water turbidity was tracked using satellite images. • Interaction of water level and rainfall is probably the main environmental driver. Surface water turbidity (SWT), as a low-cost proxy of surface suspended sediment, is important for characterizing the hydro-ecological process and light availability in the lake or reservoir ecosystem. In this study, we proposed the combined use of HJ-1 charge-coupled device imaging and field observation to track the long-term SWT dynamics with environmental changes in Lakes Gaoyang, Hanfeng, and Changshou of the Three Gorges Reservoir, China. In situ remote sensing reflectance spectra were utilized to develop the characteristic spectral indexes for the SWT estimation in different water optical classes separated by a density peaks-based classification. Significant correlations were found between the red-, four-band, band ratio spectral indexes and SWT (determination coefficient >0.71 and root-mean-square error <8.32 nephelometric turbidity unit), suggesting a crucial role of the class-specific retrieval models for the SWT estimation in optically complex waters. The proposed method was further used to monitor the spatio-temporal SWT dynamics over the three lakes from 2008 to 2019, demonstrating that the significant SWT decline in Lakes Gaoyang and Hanfeng and the relatively stable trend in Lake Changshou during the 11-year period. Specifically, the SWT decreasing trends may be attributed to the water level linkage mechanism of Three Gorges and Wuyang Dams. In addition, analyses with simultaneous environmental factors showed that the seasonal and inter-annual variations of SWT appear to be closely correlated with water level and rainfall. Long-term remote tracking of the SWT dynamics presented in this study could provide new insight and reference for reservoir management in the post-Three Gorges Project Era. [ABSTRACT FROM AUTHOR]