China’s coastal zone shifts from land-dependent to green and sustainable development

Abstract

Coastal reclamation poses a significant threat to the ecological integrity and sustainability of China’s coastal zone, prompting the implementation of stricter regulatory controls in recent years. However, a comprehensive understanding of long-term reclamation dynamics and the effectiveness of conservation initiatives over the past few decades remains limited. This study first quantified reclaimed areas and analyzed their spatial variability across multiple spatiotemporal scales using remote sensing-based land use and land cover change dataset (1990−2020). We then evaluated long-term trends in reclamation activities in relation to economic growth and policy interventions, which were hypothesized as primary drivers of reclamation dynamics. Our results indicate that land reclamation occurred extensively across all coastal regions, with the largest cumulative reclaimed areas concentrated in Shandong, Liaoning, and Jiangsu provinces. Each of these provinces exceeded 1,800 km², collectively accounting for approximately 11,592.0 km² of reclaimed land from 1990 to 2020. Reclamation expanded rapidly during 2000−2012 (40.9 km²/yr), followed by a pronounced decline post-2012 (−38.0 km²/yr). This transition coincided with the implementation of policy-driven conservation measures, including the establishment of protected areas. Nevertheless, substantial spatial heterogeneity in reclamation patterns persisted, which reflected the influence of local development priorities and the variable effectiveness of regional conservation strategies. These findings suggest that China’s coastal zone is undergoing a transformative shift from land-dependent development toward greener and more sustainable pathways. This study provides robust scientific evidence to support coastal management and offers critical insights for policymakers and stakeholders addressing coastal sustainability challenges at both regional and global scales.

Keywords

Coastal reclamation / Land use and land cover change / patiotemporal dynamics / Protected area / Policy-driven impact

Declaration of generative AI in scientific writing

During the preparation of this work the authors used DeepSeek in order to improve the readability and language of the manuscript. After using this tool, the authors reviewed and edited the content as needed and take full responsibility for the content of the publication.

Declaration of competing interests

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Xiangming Xiao is an Editorial Board Member for this journal and was not involved in the editorial review or the decision to publish this article.

Data availability statement

Current Landsat Collection 2 Level-2 (OLI/ETM+/TM) surface reflectance (SR) data are available through the Google Earth Engine cloud-processing platform (Landsat 8: https://developers.google.com/earth-engine/datasets/catalog/LANDSAT_LC08_C02_T1_L2; Landsat 7: https://developers.google.com/earth-engine/datasets/catalog/LANDSAT_LE07_C02_T1_L2; Landsat 5: https://developers.google.com/earth-engine/datasets/catalog/LANDSAT_LT05_C02_T1_L2). GLC_FCS30D dataset is acquired from https://zenodo.org/records/8239305. Provicial GDP and population data is acquired from National Bureau of Statistics of the People’s Republic of China (available at: https://www.stats.gov.cn/sj/ndsj/). Nighttime light dataset is download from the Google Earth Engine platform: https://developers.google.com/earth-engine/datasets/catalog/NOAA_VIIRS_DNB_ANNUAL_V22. Protected areas data is acquired from International Alliance of Protected Areas dataset (http://iapa.globalzoology.org.cn/).

CRediT authorship contribution statement

Xinxin Wang: Writing - review & editing, Writing - original draft, Visualization, Validation, Supervision, Software, Resources, Project administration, Methodology, Investigation, Funding acquisition, Formal analysis, Data curation, Conceptualization. Yuhan Zheng: Writing - review & editing, Writing - original draft, Visualization, Validation, Methodology, Investigation, Funding acquisition, Formal analysis, Data curation. Xiangming Xiao: Writing - review & editing, Supervision, Resources, Conceptualization. Xubang Wang: Writing - review & editing, Visualization, Software. Jihua Wu: Writing - review & editing, Supervision. Ming Nie: Writing - review & editing, Funding acquisition. Ruiting Ju: Writing - review & editing. Qiang He: Writing - review & editing. Qutu Jiang: Writing - review & editing. Guanqiong Ye: Writing - review & editing. Lijuan Cui: Writing - review & editing. Bo Li: Writing - review & editing, Supervision, Resources, Project administration, Funding acquisition, Conceptualization.

Acknowledgements

This study was sponsored by National Natural Science Foundation of China (Grants No. 32330065, 32430065, 42201341, and 32501456), National Key Research and Development Program of China (Grant No. 2022YFF0802400), the Joint Research Fund of the “Island Atmosphere and Ecology” Category IV Peak Discipline (Grant No. QN202504), and State Key Laboratory of Wetland Conservation and Restoration-Wetland Young Scientist Program (Grant No. SDGZ-QN2025-01).

Supplementary materials

Supplementary material associated with this article can be found, in the online version, at doi:10.1016/j.geosus.2026.100434.

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