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Due to the growing demand for land resources, coastal reclamation has become a global land use practice. Although the reclamation of coastal wetlands brings substantial economic benefits, it can lead to a series of adverse ecological impacts. Considerably, economic and ecological trade-offs of reclamation activities must be analyzed to make targeted land use policy decisions. This study focuses on land reclamation on the east coast of China, taking Hangzhou Bay as a case study. Remote sensing techniques were used to detect the coastline and landscape changes in the reclaimed areas from 1985 to 2015. Subsequently, field surveys and empirical parameters were employed to evaluate the impact on coastal ecosystem services. Finally, the monetary analysis was used to evaluate the trade-offs between ecological loss and economic gain due to land reclamation. The results showed that a total of 75134.3 ha of coastal wetlands (accounting for 8.58% of the total land area) were reclaimed from 1985 to 2015 in the Hangzhou Bay. A substantial decline in ecosystem service value (ESV) was observed with a drop from 866,400 Yuan ha−1 in 1985 to 285,800 Yuan ha−1 in 2015 due to the conversion of natural to artificial landscape. The total ESV loss exceeded the economic benefits throughout the study period, thus the economic benefits failed to compensate for the ESV loss. This trade-off relationship resulted from reclamation expansion on short-term economic benefits at the expense of long-term ecological value. According to these findings, we propose three main ways to achieve a “win–win” situation between gains and loss of reclamation for sustainability.

Accurately quantifying the variation of urban green space is the prerequisite for fully understanding its ecosystem services. However, knowledge about the spatiotemporal dynamics of urban green space is still insufficient due to multiple challenges that remain in mapping green spaces within heterogeneous urban environments. This paper uses the city of Hangzhou to demonstrate an analysis methodology that integrates sub-pixel mapping technology and landscape analysis to fully investigate the spatiotemporal pattern and variation of hierarchical urban green space patches. Firstly, multiple endmember spectral mixture analysis was applied to time series Landsat data to derive green space coverage at the sub-pixel level. Landscape metric analysis was then employed to characterize the variation pattern of urban green space patches. Results indicate that Hangzhou has experienced a significant loss of urban greenness, producing amore fragmented and isolated vegetation landscape. Additionally, a remarkable amelioration of urban greenness occurred in the city core from 2002 to 2013, characterized by the significant increase of small-sized green space patches. The green space network has been formed as a consequence of new urban greening strategies in Hangzhou. These strategies have greatly fragmented the built-up areas and enriched the diversity of the urban landscape. Gradient analysis further revealed a distinct pattern of urban green space landscape variation in the process of urbanization. By integrating both sub-pixel mapping technology and landscape analysis, our approach revealed the subtle variation of urban green space patches which are otherwise easy to overlook. Findings from this study will help us to refine our understanding of the evolution of heterogeneous urban environments. [ABSTRACT FROM AUTHOR]