An urban agglomeration is the engine of regional and national economic growth, but also causes many ecological and environmental issues that emerge from massive land changes. In this study, the spatiotemporal evolution of an urban agglomeration was quantified and its impacts on the urban and regional landscape patterns were evaluated. It showed that the urbanized land area of the Pearl River Delta Urban Agglomeration (PRDUA) in China nearly quadrupled, having linearly increased from 1819.8 km2 to 7092.2 km2 between 1985 and 2015. The average annual growth rate presented a bimodal wave-like pattern through time, indicating that the PRDUA has witnessed two rounds of the urbanization process. The growth modes (e.g., leapfrog, edge-expansion, infilling) were detected and they exhibited co-existing but alternating dominating patterns during urbanization, demonstrating that the spatiotemporal evolution of the urban development of the PRDUA follows the “spiral diffusion-coalescence” hypothesis. The morphology of the PRDUA presented an alternating dispersal-compact pattern over time. The city-level and regional-level landscape patterns changed synchronously with the spatiotemporal evolution of the PRDUA over time. The urbanization of the PRDUA increased both the complexity and aggregation of the landscape, but also resulted in an increasing fragmentation and decreasing connectivity of the natural landscape in the Pearl River Delta region. These findings are helpful for better understanding how urban agglomerations evolve and in providing insights for regional urban planning and sustainable land management.

Payments for ecosystem services (PES) are designed to reduce the impact of human activities on eco-sensitive areas. PES programs often adopt economic-incentive and command-control strategies. Increasing the enthusiasm of farmers’ participation is crucial for the sustainability of PES programs and ecosystem restoration. The watershed ecological compensation in Xin’an River Basin is the first horizontal ecological compensation pilot in China. In this study, economic-incentive strategy and command-control strategies in living and farming are implemented simultaneously to improve water quality. Under the collective action framework, we analyze the drivers of farmers’ participation in three concurrent strategies using hierarchical linear models (HLM). The results show: (1) Overall, 81.79%, 76.26%, and 79.11% of farmers are willing to participate in economic-incentive strategy, command-control strategy in living, and command-control strategy in farming, respectively, while 18.21%, 23.74%, and 20.89% are from the village level. (2) Among statistically significant (p < 0.01) factors at the farmer level, social trust (β = 0.305), and social participation (β = 0.134) have positive effects on the economic-incentive strategy; the number of communication and entertainment equipment has a positive effect on the willingness to participate in command-control strategy in living (β = 0.287) and command-control strategy in farming (β = 0.336). (3) At the village level, village characteristics have a direct impact on the farmers’ willingness to participate in strategies. Village woodland area is positively correlated with strategies participation. In addition, village characteristics play a moderating role by influencing farmers’ sustainable livelihood capital. We conclude that different concurrent strategies and collective actions need to be considered in the design of PES programs, particularly in ecologically sensitive areas, which can enrich the theory of collective action and the connotation of PES.

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