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Coastal land reclamation has been practiced widely to accommodate rapid urbanization. But the exploitation of coastal wetlands also imposes ecological risks and jeopardizes ecological security in many countries. The overall effects of coastal land reclamation must therefore be assessed. We developed a conceptual framework to evaluate the ecological effects of coastal land reclamation on cropland protection along three dimensions: land quantity, ecological environment, and land quality. An integrated index system was constructed accordingly and tested by using data from Cixi, a coastal city in eastern China. Our index system generated rich information to assess the impacts of reclamation on added cropland area, landscape ecological risk, and cropland soil quality. The results showed that between 1985 and 2020, a total area of 393.71 km2 of coastal wetlands were reclaimed in Cixi City, which played a crucial part in upholding the equilibrium between the land supply and demand during urbanization. However, its adverse ecological effects were also evidenced. Coastal reclamation not only increased the landscape disturbance and ecological risk but also significantly decreased the overall cropland soil quality. The city's original reclamation‐driven development strategy is unable to meet the updated requirements of "quantity‐quality‐ecological balance" for cropland protection. Our index system can help land use policymakers monitor the ecological effects of coastal reclamation. The knowledge gained will have major policy implications for the land use management that promotes sustainability in coastal regions. [ABSTRACT FROM AUTHOR]

Coastal reclamation has been used widely to accommodate urbanization and support increasing food demand. However, the responses of soil properties and soil-related ecosystem services (SES) to reclamation remain unclear. There are no effective operational methods for calculating the SES provided by reclaimed cropland. Using field sampling data of soil properties, we proposed a framework to evaluate the influence of reclamation on the soil's ability to provide five SESs: plant growth support (SES1), carbon storage (SES2), nutrient cycling (SES3), erosion control (SES4), and habitat provision (SES5). A series of SES indices were constructed accordingly and tested using data from a reclaimed soil chronosequence over 700 years in Hangzhou Bay, China. The results showed that all the SES indices increased significantly along the reclamation chronosequence, with the highest impact for SES2 (273.7% of soil C storage growth) owing to long-term continuous cultivation and fertilization. Most of the indices have a different logarithmic relationship with reclamation time, with a faster growth rate in the first 50 years, while SES1 increases linearly with reclamation time. Using soil organic matter as a reference, the sensitivity of SESs to reclamation is SES4 > SES2 > SES5 > SES3 > SES1. The significant positive correlations between all SES indices suggest that the provision of the five SESs is interdependent, with strong synergy. Our methods and index system can be effectively used to monitor coastal cropland protection and promote sustainable management of reclaimed land. • A framework was proposed to assess the impact of coastal reclamation on soil-related ecosystem services (SES). • Soil properties and SES were analyzed in a chronosequence of coastal reclamation. • SES increased with reclamation time in Hangzhou Bay. • Significant positive correlations between SESs indicated they have strong synergies. [ABSTRACT FROM AUTHOR]

Arable land in China is undergoing significant changes, with massive losses of arable land due to rapid urbanization and the reclamation of arable land from other lands to compensate for these losses. Many studies have analyzed arable land loss, but less attention has been paid to land reclamation, and the utilization of reclaimed land remains unclear. The goal of our study was to characterize the patterns and efficiency of the utilization of reclaimed land and to identify the factors influencing the land utilization process inWenzhou using remote sensing, geographic information systems and logistic regression. Our results showed that only 37% of the total reclaimed land area was under cultivation, and other lands were still bare or had been covered by trees and grasses. The likelihood that reclaimed land was used for cultivation was highly correlated with the land use type of its neighboring or adjacent parcels. Reclaimed land utilization was also limited at high elevations in lands with poor soil fertility and in lands at a great distance from rural residential areas. In addition, parcels located in the ecological protection zone were less likely to be cultivated. Therefore, we suggest that the important determinants should be considered when identifying the most suitable land reclamation areas. [ABSTRACT FROM AUTHOR]

• Coastal reclamation in Hangzhou Bay from 1985 to 2015 were explored. • Land reclamation has greatly degraded ecosystem service value of coastal wetlands. • Economic gain failed to compensate for ecosystem service value loss in coastal reclamation. • The strict prohibition on coastal reclamation poses a big challenge to local governments. 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. [ABSTRACT FROM AUTHOR]