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In China, hydropower development is an important strategic initiative for the structural reform of energy supply and the development of poor areas. With technology at a mature stage, hydropower development is now constrained by relocation issues. Building a mechanism to balance the interests of all the stakeholders is the key to realizing the shared benefits of hydropower development. This paper takes reservoir-displaced people, hydropower developers, and government departments as the research objects, combines the relationship between them, and constructs two evolutionary game models: "reservoir-displaced people versus hydropower developer" and "reservoir-displaced people versus hydropower developer versus government department." We then analyze strategy selection and evolution for reservoir-displaced people and hydropower developers, as well as the changes in the evolutionarily stable strategies of both players under the government's macro-control and determine the boundary conditions for stable behavior of each player. Based on the results of the evolutionary analysis, the initial willingness and parameters of the players can be input into a simulation, and the evolutionary paths under different scenarios are calculated in MATLAB to further verify and analyze the evolutionary results. According to the boundary conditions of the different strategies they adopt, the equilibrium point of benefits for the three players can be calculated, which provides a new research framework for the formulation of land acquisition compensation policy, and also provides an idea and scientific basis for the macro regulation of the distribution of the benefits of hydropower development. [ABSTRACT FROM AUTHOR]

Human activities currently play a dominant role in shaping and eroding Earth's biodiversity, but the historical dynamics leading to this situation are poorly understood and contentious. Importantly, these dynamics are often studied and discussed without an emphasis on cultural evolution, despite its potential importance for past and present biodiversity dynamics. Here, we investigate whether cultural filtering, defined as the impact of cultural evolution on species presence, has driven the range dynamics of five historically widespread megafauna taxa (Asiatic elephant, rhinoceroses, tiger, Asiatic black bear, and brown bear) across China over the past 2 millennia. Data on megafauna and sociocultural history were compiled from Chinese administrative records. While faunal dynamics in China are often linked to climate change at these time scales, our results reveal cultural filtering as the dominant driver of range contractions in all five taxa. This finding suggests that the millennia-long spread of agricultural land and agricultural intensification, often accompanied by expansion of the Han culture, has been responsible for the extirpation of these megafauna species from much of China. Our results suggest that cultural filtering is important for understanding society's role in the assembly of contemporary communities from historical regional species pools. Our study provides direct evidence that cultural evolution since ancient times has overshadowed climate change in shaping broadscale megafauna biodiversity patterns, reflecting the strong and increasing importance of sociocultural processes in the biosphere. [ABSTRACT FROM AUTHOR]

Human activities produced great impacts on wetlands worldwide. Taking Jiangsu Province, China, as a representative wetland region subject to extensive human activities, the aim of this study is to understand the conversion trajectory and spatial differentiation in wetland change from a multi-scale perspective. Based on multi-temporal Landsat images, it was found that the natural wetlands decreased by 11.2% from 1990 to 2006 in Jiangsu Province. Transition matrices showed that the conversion of natural wetlands to human-made wetlands (mostly aquaculture ponds) was the major form of natural wetland reduction, accounting for over 60% of the reduction. Percentage reduction and area reduc tion of natural wetlands were respectively quantified within different wetland cover zones using a moving window analysis. Average percentage reduction showed a decreasing tendency with increasing wetland cover. The high-cover and mid-cover zone presented the largest area reduction at the scales of 1-2 km and 4-8 km, respectively. Local hotspots of natural wetland reduction were mapped using the equal-interval and quantile classification schemes. The hotspots were mostly concentrated in the Lixiahe marshes and the coastal wetland areas. For the area reduction hotspots, the quantile classification presented larger area and more patches than the equal-interval classification; while an opposite result was shown for the percentage reduction hotspots. With respect to the discontinuous distribution of the natural wetlands, area reduction could be more appropriate to represent reduction hotspots than percentage reduction in the study area. These findings could have useful implications to wetland conservation. [ABSTRACT FROM AUTHOR]

Urbanization produced significant landscape changes throughout the world. China has been experiencing accelerated urbanization during the past decades. Rapid land use/land over conversion occurred nationwide in urbanization, manifesting noteworthy characteristics of landscape dynamics. In this study, we investigated the spatial differentiation in settlement change rates among 1-km land units in the Nanjing metropolitan region, a representative rapidly urbanizing region in China. Remotely sensed detection using Landsat TM data of 1988-2006 showed that settlement increase, termed as positive growth (PG), was predominant in the study area; while settlement decrease, termed as negative growth (NG), also had a considerable proportion, which was mainly attributed to the increase of green lands and the shrink of rural settlements. Along the urban-rural gradient, PG and NG showed similar mono-peaked patterns. The urban fringe zone with a consistent width of about 4 km was identified as the hot zone of both PG and NG over the three unequal periods. For both PG and NG, high-rated changes tended to exhibit more aggregative patterns along the gradient in the urban fringe zone. Settlement changes showed apparent anisotropy across directions. The directional distribution of PG was significantly negatively correlated to the topographic variables, suggesting that the mountains constrained urban expansion in an 'area-weighted inverse-distance power' form. Significant correlation between PG and NG in a time-lagged manner showed the 'increase-decrease' fluctuation occurred in settlement changes, reflecting the 'urban expansion-land reconfiguration' process in rapid urbanization in Nanjing. [ABSTRACT FROM AUTHOR]

Natural wetlands, occupying 3.8% of China's land and providing 54.9% of ecosystem services, are unevenly distributed among eight wetland regions. Natural wetlands in China suffered great loss and degradation (e.g., 23.0% freshwater swamps, 51.2% costal wetlands) because of the wetland reclamation during China's long history of civilization, and the population pressure and the misguided policies over the last 50 years. Recently, with an improved understanding that healthy wetland ecosystems play a vital role in her sustainable economic development, China started major efforts in wetland conservation, as signified by the policy to return reclaimed croplands to wetlands, the funding of billions of dollars to restore degraded wetlands, and the national plan to place 90% of natural wetlands under protection by 2030. This paper describes the current status of the natural wetlands in China, reviews past problems, and discusses current efforts and future challenges in protecting China's natural wetlands. [ABSTRACT FROM AUTHOR]

The increasing availability of 3-D urban data yields new insights into urban developments and their implications for population density, energy consumption, and the carbon budget. However, existing products of urban building heights at a regional or global scale are mostly subject to coarse grid size or long-time lags. Fine-resolution building height maps remain unavailable for most regions to present recent vertical information. Also, the lack of sampled building heights with spatial and temporal consistency at larger scales makes it difficult to update building height maps. The newly available spaceborne lidar data from the Global Ecosystem Dynamics Investigation (GEDI) are expected to overcome these critical barriers. Here we propose a generalizable approach to mapping large-scale distributions of building heights by fusing GEDI-derived relative height metrics, optical data (i.e., Landsat-8 and Sentinel-2), and radar data (Sentinel-1). We applied our approach to the Yangtze River Delta region (YRD), one of China's largest urban agglomerations. We investigated the availability of building height samples generated from GEDI-based relative height metrics and the optimal grid size of building height mapping into 30-m (about footprint level) and 150-m (regional level) grid sizes. We finally developed a random forest model using active and passive sensors to extrapolate GEDI-derived samples discretely to the continuous building height map at the 150-m grid size in 2019. We revealed the spatial distribution patterns of building heights and the urbanization effect on the city's mean building heights in the YRD region. We found that: (1) GEDI-derived building height samples were highly consistent with the reference building height data at the footprint (i.e., Pearson's r = 0.86, RMSE = 9.25 m, n = 237) and regional (i.e., Pearson's r = 0.76, RMSE = 6.36 m, n = 69) levels. (2) The Pearson's correlation coefficient (r) and root mean square error (RMSE) of the final spatially continuous and up-to-date building height map were 0.85 and 5.03 m, respectively. (3) The resulting map showed a strong positive correlation between the city's mean building height and urbanization level. Our work makes it possible to use remotely sensed data to make global maps of building heights at a 150-m scale. • Generate building height sample from GEDI relative height metrics. • The spatially continuous building height map with 150-m grid size is obtained. • The effect of urbanization on the city's mean building height is investigated. • Synthesize of optical and radar data can improve the accuracy of the building height estimation. [ABSTRACT FROM AUTHOR]