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This paper develops a lexicographic optimization model to allocate agricultural and non-agricultural water footprints by using the land area as the influencing factor. An index known as the water-footprint-land density (WFLD) index is then put forward to assess the impact and equity of the resulting allocation scheme. Subsequently, the proposed model is applied to a case study allocating water resources for the 11 provinces and municipalities in the Yangtze River Economic Belt (YREB). The objective is to achieve equitable spatial allocation of water resources from a water footprint perspective. Based on the statistical data in 2013, this approach starts with a proper accounting for water footprints in the 11 YREB provinces. We then determined an optimal allocation of water footprints by using the proposed lexicographic optimization approach from a land area angle. Lastly, we analyzed how different types of land uses contribute to allocation equity and we discuss policy changes to implement the optimal allocation schemes in the YREB. Analytical results show that: (1) the optimized agricultural and non-agricultural water footprints decrease from the current levels for each province across the YREB, but this decrease shows a heterogeneous pattern; (2) the WFLD of 11 YREB provinces all decline after optimization with the largest decline in Shanghai and the smallest decline in Sichuan; and (3) the impact of agricultural land on the allocation of agricultural water footprints is mainly reflected in the land use structure of three land types including arable land, forest land, and grassland. The different land use structures in the upstream, midstream, and downstream regions lead to the spatial heterogeneity of the optimized agricultural water footprints in the three YREB segments; (4) In addition to the non-agricultural land area, different regional industrial structures are the main reason for the spatial heterogeneity of the optimized non-agricultural water footprints. Our water-footprint-based optimal water resources allocation scheme helps alleviate the water resources shortage pressure and achieve coordinated and balanced development in the YREB.

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City managers need to understand how land use and land cover (LULC) change in an urban landscape can affect future land degradation and conditions for ecosystem services (ESs) supply and demand. Optimal land use and land management requires explicit spatial mapping of ESs supply and demand under alternative land use scenarios. In this study, we applied spatially explicit models to predict changes in ESs supply and demand, and their coupling mechanisms, under one baseline scenario and three stakeholder-defined LULC change scenarios (developed, planning, policy) in Shanghai municipality, China. The results suggest that the policy scenario could significantly increase ESs supply and restore degraded urban areas, but would not guarantee that supply meets demand for four key ESs tested: water retention, particulate matter removal, carbon sequestration, and recreation. However, the policy scenario significantly reduced the shortfalls and spatial mismatches in water retention, particulate matter removal and recreation services, and also greatly restored deficit areas for all four ESs. This is valuable scientific evidence that ESs supply and demand information can be incorporated into urban land management planning in a spatially explicit manner, in order to control or prevent future potential land degradation.

Urban wetlands play a significant role in the sustainable development of the urban eco-environment. However, accelerated urbanization has caused rapid changes in urban wetland landscape patterns, which may seriously affect their functions. Based on land-use maps, TM images, and field data from the Wuhan wetlands, the spatiotemporal evolution and wetland landscape pattern were quantitatively analyzed, with reference to landscape ecology indices of diversity, fragmentation, dominance, shape, and dimension. The results showed that: (1) the natural wetland area decreased: lake wetlands and marsh wetlands decreased by 18.71% and 50.3% from 1987 to 2005, respectively; (2) artificial wetland area increased by 47.75% in Wuhan over the same period; (3) the lake wetland area of Wuhan declined due to the conversion of large lakes to smaller ones; (4) the value of the diversity index (H), evenness index (E), and fragmentation index (F) decreased, while the value of the dominance index (D) increased from 1987 to 2005; (5) the landscape shape index (LSI) and fractal dimension (FD) of the river wetlands, lake wetlands, bottomland wetlands, and marsh wetlands decreased, while the LSI and FD of the reservoir and pond wetlands increased from 1987 to 2005; and (6) natural, societal, and economic, as well as human, activities are major factors for the structural changes in the Wuhan wetland landscape, as revealed by canonical correlation analysis. Results suggest that the ecological environment of urban wetlands should be protected to maximize the services of urban wetland ecosystems in Wuhan, China.

Aims We aimed to evaluate the impact of the COVID-19 epidemic on emergency and cardiovascular disease-related calls in Hangzhou, China. Methods We conducted a single-center retrospective study, collecting data on emergency calls to the Hangzhou Emergency Center (HEC) during the COVID-19 epidemic (January 20, 2020, to March 15, 2020. Data were compared with the same period in 2019. Results Compared to 2019, the number of emergency calls has dropped by 21.63%, ambulance calls by 29.02%, rescue calls by 22.57%, and cardiovascular disease-related emergency calls by 32.86%. The numbers of emergency, ambulance, and rescue calls in 2020 were significantly lower than in 2019. Conclusions During the COVID-19 epidemic in Hangzhou, the numbers of emergency and cardiovascular disease-related calls have decreased significantly. These results point to a severe social problem that requires the attention of the medical community and the government.