Jianjun Zhang

China has implemented long-term and large-scale initiatives to address land and ecosystem sustainability challenges, yet their ecological outcomes and regional differentiation remain insufficiently synthesized within a unified ecological regionalization framework. This study integrates government policies and planning documents, official reports and news, academic publications, and spatial ecological datasets to assess China’s ecological protection and restoration practices and to identify major ecological problems and strategic orientations across 57 ecodistricts. A total of 472 documentary records were retained after screening, and spatial assessments of soil erosion sensitivity, sandification sensitivity, rocky-desertification sensitivity, and vegetation change were conducted using harmonized ecological regionalization units. Between 2005 and 2020, approximately 4.1% of the mapped area experienced ecosystem-type change, while vegetation exhibited an overall greening tendency. National monitoring also indicates continued reductions in soil and water loss, sandification, and rocky desertification. However, ecological pressures remain strongly differentiated among regions, and more than 80% of ecodistricts face three or more major ecological problems. Dominant strategic orientations also vary spatially: protection-oriented strategies are more common in relatively intact and less disturbed regions, restoration-oriented strategies are concentrated in areas with stronger degradation and human disturbance, and integrated protection–restoration strategies occur mainly where conservation and intensive land use coexist. These findings demonstrate that China has achieved substantial overall ecological improvement, but recovery remains spatially uneven and constrained by overlapping pressures. China’s experience suggests that long-term commitment, sustained investment, ecological regionalization, and differentiated interventions are important for ecosystem sustainability, while context-specific adaptation and explicit consideration of social–ecological trade-offs are essential for broader transferability.

In the context of global climate change and the green transformation of the tourism industry, low-carbon tourism has emerged as an important topic within the field of sustainable development research. Consequently, there is a pressing need to systematically review and synthesize its knowledge domain. This study utilizes bibliometric analysis, employing CiteSpace, to review 468 articles published in the Web of Science Core Collection from 2010 to 2026, thereby elucidating publication trends, keyword clustering, and research hotspots within the field of low-carbon tourism. Additionally, it employs content analysis to provide an in-depth discussion of the knowledge system in this research area. Key findings are as follows: (1) The number of published papers on low-carbon tourism exhibits a phased growth pattern, with contributions predominantly centered around scholars such as Gössling and institutions such as the Chinese Academy of Sciences. Moreover, keyword co-occurrence and clustering analyses uncover a development from essential concepts such as low-carbon tourism and climate change to a more extensive range of themes, including carbon emission accounting, tourist behavior, and systemic governance, and research topics have undergone a phased evolution, moving from macro-level cognition to quantitative analysis, and then to systemic governance. (2) The research hotspots encompass five key areas: basic cognition and related concepts, carbon emission accounting methods and applications, factors influencing emissions and assessment frameworks, tourists’ low-carbon behaviors and decision-making mechanisms, and pathways for multi-party collaborative governance. (3) Current research is still facing four challenges, i.e., the absence of a standardized framework for assessing carbon emissions, outdated assessment methods, a disconnect between behaviors and governance, and fragmented governance entities. This indicates that research on low-carbon tourism has progressed beyond the initial macro-level discussions and has entered a critical phase closely linked to substantive governance. Future research needs to focus on deeply exploring the standardization of accounting methods, the development of dynamic assessment models, the design of behavioral intervention mechanisms, and the establishment of multi-level collaborative governance mechanisms. These efforts are essential to provide scientific evidence and practical guidelines for the global tourism industry to achieve neutrality goals.

The Gross Ecosystem Product (GEP) represents the total value of goods and services supplied by ecosystems, serving as a key indicator that connects ecological well-being with economic development and supports the achievement of sustainable development goals. This study selected Beijing’s Wild Duck Lake National Wetland Park as its research subject, establishing a GEP assessment system for two major services: regulating services and cultural services. By integrating market-based valuation approaches with social media data to support the assessment of cultural services, this study calculated the 2023 GEP of the wetland park. Finally, based on the social media data and the GEP accounting results, value enhancement strategies for Wild Duck Lake National Wetland Park were proposed. Key findings include: (1) The total GEP of Wild Duck Lake National Wetland Park reached 155.01 million CNY in 2023, with a per-unit-area value of 35.47 million CNY/km². (2) Among regulating services, climate regulation and water purification were the primary contributors, accounting for 66.10% and 11.76% of the total value, respectively. Cultural service value primarily derived from tourism and health preservation services. (3) Social media analysis showed that visitors valued the park’s natural landscapes while noting service and facility shortcomings, indicating a balanced assessment combining both positive and negative perceptions. (4) Based on GEP assessment and social perception analysis, this study provides pathways for realizing the ecosystem service value of Wild Duck Lake National Wetland Park from three aspects. The main contribution of this study lies in developing an integrated framework for GEP accounting and enhancement in national wetland parks, providing a scientific foundation for their sustainable development.

Rapid regional development and intensified human activities increasingly disturb ecosystems, posing substantial threats to the integrity of large-scale ecological zones. As a World Natural Heritage site and a crucial national ecological zone, the Zhangjiajie Scenic Area plays a pivotal role in China’s environmental conservation efforts. To comprehensively assess tourism ecological security in the Scenic Area and strengthen the scientific basis for resource management and policymaking, this study developed a multi-dimensional ecological security evaluation system covering 2010–2024, incorporating dynamic changes in perturbation, reaction, and governance. Using entropy weight–TOPSIS and coupling coordination models, combined with obstacle degree analysis, we examined the temporal trajectory of ecological security and analyzed its underlying driving mechanisms. The study also examined factors influencing the sustainable development of the ecosystem. The results indicate the following: (1) Tourism ecological security in the Scenic Area followed a V-shaped trajectory of “rapid degradation—steady recovery—impact and rebound.” It declined sharply to an unsafe level between 2010 and 2014, steadily recovered from 2015 to 2019, briefly dropped in 2020, and then rebounded, reaching a peak evaluation value of 0.519 in 2024. (2) The co-evolution of perturbation, reaction, and governance subsystems has matured: their coupling coordination degree has increased annually and has remained at the level of “intermediate coordination” since 2020. The reaction subsystem plays a central role, serving as a bridge between perturbation and governance. (3) The driving factors exhibit a phased evolutionary pattern of “elements—facilities—structure—function.” Cultivated land area, total road mileage, and artificial afforestation area constitute the main long-term constraints. This research provides important insights for strengthening ecological security and sustainability in the Scenic Area while advancing regional ecosystem development. It also offers valuable guidance for ecological security management and policymaking in similar nature reserves.

Detecting tree cover is crucial for sustainable land management and climate mitigation. Here we develop an automatic detection algorithm using high-resolution satellite data (<5 m) to map pan-tropical tree cover (2015–2022), enabling identification and change analysis for previously undetected tree cover (PUTC). Our findings reveal that neglecting PUTC represents 17.31 ± 1.78% of the total pan-tropical tree cover. Tree cover net decreased by 61.05 ± 2.36 Mha in both forested areas (63.93%) and non-forested areas (36.07%) between 2015 and 2022. Intense changes in tree cover are primarily observed in regions with PUTC, where the World Cover dataset with a resolution of 10 m often fails to accurately detect tree cover. We also conduct a sensitivity analysis to quantify the contributions f climate factors and anthropogenic impacts (including human activities and land use cover change) to tree cover dynamics. Our findings indicate that 43.98% of tree cover gain is linked to increased precipitation, while 56.03% of tree cover loss is associated with anthropogenic impacts. These findings highlight the need to include undetected tree cover in strategies combating degradation, climate change, and promoting sustainability. Fine-scale mapping can improve biogeochemical cycles modeling and vegetation-climate interactions, improving global change understanding.