Regional Carbon Sink Research Articles

The effect of afforestation on a regional carbon sink: a case study in the Yangtze River Delta, China

The effect of afforestation on a regional carbon sink: a case study in the Yangtze River Delta, China

Enhancing natural carbon sinks: Simulation of land use change under different carbon market scenarios by developing an ANN-ABM model

The carbon market mechanism presents an innovative approach to achieving carbon neutrality, however, its impact on regional carbon sink enhancement remains uncertain. This paper proposes an analysis framework based on an Artificial Neural Network-Agent-Based Model (ANN-ABM) to simulate the potential contribution of carbon market mechanism in enhancing carbon sinks. Taking the case of Chongming, China, the results demonstrate significant economic potential with forest land expansion from 2010 to 2020, equivalent to 30.69 % of eco-compensation. Under scenarios introducing a carbon market, there is an increased probability of converting land to high carbon sink types. Compared to the baseline scenario, carbon prices at 1.34 US$/t and 6.27 US$/t result in additional funds of 8.94 % and 41.46 %, respectively, and increase the carbon sink by 12.52 % and 30.28 %. The findings contribute to an understanding of how the value of carbon sinks can be realized through market mechanism and offer guidance for innovative eco-compensation approaches.

The impact of different grazing intensity and management measures on soil organic carbon density in Zhangye grassland

Studying the spatial and temporal changes of grassland soil organic carbon (SOC) is helpful in promote the management of regional ecosystem carbon sinks. Grazing is one of the main ways of rational utilization of grassland. Different grazing intensities will affect the change of SOC density. Under different grazing intensity and management measures in Zhangye grassland, this study uses the parameter localized CENTURY model to simulate the temporal and spatial variations of SOC density from 1970 to 2022. The results showed that long-term light grazing reduced the average SOC by 195.114 g·m−2 and 1.91%. Moderate and severe grazing, respectively, for a long time made the total SOC density loss of 5.21% and 17.69%. In a short period, mild and moderate grazing reduced total SOC first and then increased it. Under light grazing, total SOC density appeared higher relative changes in the southeast, and lower in the northwest and central. There was no significant difference in the relative changes of total SOC between steppe and desert grasslands under light grazing. The decrease range of steppe was gradually greater than that in desert grassland. Since different management measures were implemented in some sampling sites in 2017, we divided the study period into two periods, 1970–2016 and 2017–2022. The implementation of degraded grassland improvement, fallow grazing, and rotational grazing would increase the total SOC density and mild SOC density, rotational grazing > degraded grassland improvement > rest grazing. Rotational grazing and the improvement of degraded grassland increased the density of active and inert SOC, while resting grazing decreased the density of SOC.

Controls on Early Cretaceous South Atlantic Ocean circulation and carbon burial – a climate model–proxy synthesis

Abstract. Black shale sediments from the Barremian to Aptian South Atlantic document the intense and widespread burial of marine organic carbon during the initial stages of seafloor spreading between Africa and South America. The enhanced sequestration of atmospheric CO2 makes these young ocean basins potential drivers of the Early Cretaceous carbon cycle and climate perturbations. The opening of marine gateways between initially restricted basins and related circulation and ventilation changes are a commonly invoked explanation for the transient formation and disappearance of these regional carbon sinks. However, large uncertainties in palaeogeographic reconstructions limit the interpretation of available palaeoceanographic data and prevent any robust model-based quantifications of the proposed circulation and carbon burial changes. Here, we present a new approach to assess the principal controls on the Early Cretaceous South Atlantic and Southern Ocean circulation changes under full consideration of the uncertainties in available boundary conditions. Specifically, we use a large ensemble of 36 climate model experiments to simulate the Barremian to Albian progressive opening of the Falkland Plateau and Georgia Basin gateways with different configurations of the proto-Drake Passage, the Walvis Ridge, and atmospheric CO2 concentrations. The experiments are designed to complement available geochemical data across the regions and to test circulation scenarios derived from them. All simulations show increased evaporation and intermediate water formation at subtropical latitudes that drive a meridional overturning circulation whose vertical extent is determined by the sill depth of the Falkland Plateau. The densest water masses formed in the southern Angola Basin and potentially reached the deep Cape Basin as Walvis Ridge Overflow Water. Palaeogeographic uncertainties are as important as the lack of precise knowledge of atmospheric CO2 levels for the simulated temperature and salinity spread in large parts of the South Atlantic. Overall temperature uncertainties reach up to 15 °C and increase significantly with water depth. The ensemble approach reveals temporal changes in the relative importance of geographic and radiative forcings for the simulated oceanographic conditions and, importantly, nonlinear interactions between them. The progressive northward opening of the highly restricted Angola Basin increased the sensitivity of local overturning and upper-ocean stratification to atmospheric CO2 concentrations due to large-scale changes in the hydrological cycle, while the chosen proto-Drake Passage depth is critical for the ocean dynamics and CO2 response in the southern South Atlantic. Finally, the simulated processes are integrated into a recent carbon burial framework to document the principal control of the regional gateway evolution on the progressive shift from the prevailing saline and oxygen-depleted subtropical water masses to the dominance of ventilated high-latitude deep waters.

Dynamic Replacement of Soil Inorganic Carbon under Water Erosion

The dynamic replacement of soil organic carbon represents a pivotal mechanism through which water erosion modulates soil–atmosphere CO2 fluxes. However, the extent of this dynamic replacement of soil inorganic carbon within this process remains unclear. In our study, we focused on Yuanmou County, China, a prototypical region afflicted by water erosion, as our study area. We leveraged the WaTEM/SEDEM model to quantify the dynamic replacement of soil carbon, accounted for the average annual net change in soil carbon pools, and used isotope tracer techniques to track and measure the process of the coupled carbon–water cycling. This comprehensive approach enabled us to scrutinize the dynamic replacement of soil carbon under water erosion and delineate its ramifications for the carbon cycle. Our findings unveiled that the surface soil carbon reservoir in the Yuanmou area receives an annual replacement of 47,600 ± 12,600 tons following water erosion events. A substantial portion, amounting to 39,700 ± 10,500 tons, stems from the dynamic replacement of soil inorganic carbon facilitated by atmospheric carbon. These results underscore the critical role of the dynamic replacement of soil inorganic carbon in altering the soil–atmosphere CO2 fluxes under water erosion, thereby influencing the carbon cycle dynamics. Consequently, we advocate for the integration of water erosion processes into regional carbon sink assessments to attain a more comprehensive understanding of regional carbon dynamics.

Optimal agricultural structure allocation based on carbon source/sink accounting

China has implemented policies to promote fuel ethanol development and achieve its dual-carbon goal. Under the policy, the significant modifications will occur in the allocation of land use resources within ethanol raw material cultivation regions. In the process of land use change, ensuring food provision and protecting the regional carbon sink are also crucial for sustainable development. This study explores carbon distribution in the Guiping section of the Yujiang River basin, where bioethanol raw materials are cultivated. Using the CLUE-S model, a multi-objective model prioritizing economic and ecological benefits is constructed. Four scenarios (i.e., the natural expansion scenario (NES); the food conservation scenario (FCS); the bioethanol feedstock conservation scenario (BCS), and the carbon sinks conservation scenario (CCS) are simulated, predicting land resource distribution by 2030. The total carbon sink decreased by 285.60 gC·m−2·a−1, showing a seasonal trend of higher levels in summer and lower levels in winter. In 2030, the total carbon sink decreased in the NES scenario, while it increased in the FCS and BCS scenarios. The CCS scenario had the largest increase, approximately 582.27 × 103 tC. These simulated scenarios consider various economic and environmental factors, providing a scientific basis for the efficient allocation of regional land resources. They also have significant implications for local energy, economic, and environmentally sustainable development, as well as promoting the achievement of carbon neutrality.

Dynamics of carbon sequestration in vegetation affected by large-scale surface coal mining and subsequent restoration

Surface coal development activities include mining and ecological restoration, which significantly impact regional carbon sinks. Quantifying the dynamic impacts on carbon sequestration in vegetation (VCS) during coal development activities has been challenging. Here, we provided a novel approach to assess the dynamics of VCS affected by large-scale surface coal mining and subsequent restoration. This approach effectively overcomes the limitations imposed by the lack of finer scale and long-time series data through scale transformation. We found that mining activities directly decreased VCS by 384.63 Gg CO2, while restoration activities directly increased 192.51 Gg CO2 between 2001 and 2022. As of 2022, the deficit in VCS at the mining areas still had 1966.7 Gg CO2. The study highlights that complete restoration requires compensating not only for the loss in the year of destruction but also for the ongoing accumulation of losses throughout the mining lifecycle. The findings deepen insights into the intricate relationship between coal resource development and ecological environmental protection.

Differentiation of Carbon Sink Enhancement Potential in the Beijing–Tianjin–Hebei Region of China

Carbon sink enhancement is of great significance to achieving carbon peak and carbon neutrality. This study firstly estimated the carbon sink in the Beijing–Tianjin–Hebei Region using the carbon absorption coefficient method. Then, this study explored the differentiation of carbon sink enhancement potential with a carbon sink–economic carrying capacity index matrix based on carbon sink carrying capacity and economic carrying capacity under the baseline scenario and target scenario of land use. The results suggested there was a remarkable differentiation in total carbon sink in the study area, reaching 2,056,400 and 1,528,300 tons in Chengde and Zhangjiakou and being below 500,000 tons in Langfang and Hengshui, while carbon sink per unit land area reached 0.66 ton/ha in Qinhuangdao and only 0.28 t/ha in Tianjin under the baseline scenario. Increasing area and optimizing spatial distribution of arable land, garden land, and forest, which made the greatest contribution to total carbon sinks, is an important way of enhancing regional carbon sinks. A hypothetical benchmark city can be constructed according to Qinhuangdao and Beijing, in comparison with which there is potential for carbon sink enhancement by improving carbon sink capacity in Beijing, promoting economic carrying capacity in Qinhuangdao, and improving both in the other cities in the study area.

Assessing Forest-Change-Induced Carbon Storage Dynamics by Integrating GF-1 Image and Localized Allometric Growth Equations in Jiangning District, Nanjing, Eastern China (2017–2020)

Forest and its dynamics are of great significance for accurately estimating regional carbon sequestration, emissions and carbon sink capacity. In this work, an efficient framework that integrates remote sensing, deep learning and statistical modeling was proposed to extract forest change information and then derive forest carbon storage dynamics during the period 2017 to 2020 in Jiangning District, Nanjing, Eastern China. Firstly, the panchromatic band and multi-spectral bands of GF-1 images were fused by using four different methods; Secondly, an improved Mask-RCNN integrated with Swin Transformer was devised to extract forest distribution information in 2020. Finally, by using the substitution strategy of space for time in the 2017 Forest Management and Planning Inventory (FMPI) data, local carbon density allometric growth equations were fitted by coniferous forest and broad-leaved forest types and compared, and the optimal fitting was accordingly determined, followed by the measurements of forest-change-induced carbon storage dynamics. The results indicated that the improved Mask-RCNN synergizing with the Swin Transformer gained an overall accuracy of 93.9% when mapping the local forest types. The carbon storage of forest standing woods was calculated at 1,449,400 tons in 2020, increased by 14.59% relative to that of 2017. This analysis provides a technical reference for monitoring forest change and lays a data foundation for local agencies to formulate forest management policies in the process of achieving dual-carbon goals.

Identification of Suitable Mangrove Distribution Areas and Estimation of Carbon Stocks for Mangrove Protection and Restoration Action Plan in China

Mangrove forests are significant blue carbon pools on the Earth with strong carbon sequestration capacity and play an important role in combating climate change. To improve the capacity of regional carbon sinks, China has implemented a Special Action Plan for Mangrove Protection and Restoration (2020–2025). In this context, based on the MaxEnt model, this study analyzed the important environmental factors affecting the distribution of mangrove forests, combined with the planning objectives and carbon density parameters of different regions; assessed the habitat suitability areas of China’s mangrove forests; and predicted their future carbon stock potential. The results showed the following: (1) Elevation was the most important factor affecting the overall distribution of mangrove forests in China, and the optimal elevation of mangrove distribution was 0.52 m. (2) The most suitable areas of mangrove forests in China were mainly distributed in Hainan, Guangxi, and Guangdong, which had great potential for carbon stock. Danzhou Bay and Hongpai Harbor in Hainan, Lianzhou Bay in Guangxi, and the Huangmao Sea in Guangdong are potential areas for habitat suitability but are not yet under high levels of protection. (3) Achieving the goals of this action plan was expected to increase carbon stocks by 4.13 Tg C. Other suitable areas not included in this plan could still increase carbon stocks by 7.99 Tg C in the long term. The study could provide a scientific basis for siting mangrove restoration areas and developing efficient management policies.

Spatiotemporal patterns of net regional productivity and its causes throughout Ordos, China.

A comprehensive understanding of the terrestrial carbon sink is essential for proficient regional carbon management. However, previous studies predominantly relied on net ecosystem productivity (NEP) as an indicator of regional carbon sink, overlooking the impacts of carbon emissions from physical processes and carbon leakage associated with anthropogenic activities. In this study, net region productivity (NRP), a vital metric representing carbon sink dynamics in regional multi-landscape ecosystems, was employed to systematically analyze the patterns, trends, and causes of carbon sink in Ordos. The results revealed that spatially averaged NRP in Ordos was 70.334 g·m-2·a-1, indicating a carbon sink effect. The coefficient of variation of NRP was 68.035%, with a higher NRP in the southern region. Normalized difference vegetation index (NDVI) predominantly controlled the spatial heterogeneity of NRP in Ordos, while precipitation emerged as the primary climatic factor influencing spatial differences in NRP. Regional variations in the impact of environmental factors on NRP were evident. In most areas, NRP showed a notable increasing trend influenced by various factors. Specifically, the simultaneous rise in NDVI and improvements in hydrothermal conditions contributed to the gradual elevation of NRP, each with varying degrees of influence across Ordos and its sub-regions.

Evaluate the differences in carbon sink contribution of different ecological engineering projects

China has implemented a series of ecological engineering projects to help achieve the 2060 carbon neutrality target. However, the lack of quantitative research on ecological engineering and the contribution of climate change to terrestrial carbon sinks limits this goal. This study uses robust statistical models combined with multiple terrestrial biosphere models to quantify the impact of China's ecological engineering on terrestrial ecosystem carbon sink trends and their differences according to the difference between reality and nonpractice assumptions. The main conclusions include the following: (1) since 1901, 84% of terrestrial ecosystem carbon sinks in China have shown an increasing trend, and approximately 45% of regional carbon sinks have increased by more than 0.1 g C/m2 every 10 years. (2) Considering the impact of human activities and the implementation of ecological engineering in China, approximately 56% of carbon sinks have improved, and approximately 10% of the regions whose carbon sink growth exceeds 50 g C m−2 yr−1 are mainly in the southeast coastal of China. (3) The carbon sequestration potential and effect of the Sanjiangyuan ecological protection and construction project are better than others, at 1.26 g C m−2 yr−1 and 14.13%, respectively. The Beijing–Tianjin sandstorm source comprehensive control project helps alleviate the reduction in carbon sinks, while the southwest karst rocky desertification comprehensive control project may aggravate the reduction in carbon sinks. This study clarifies the potential of China's different ecological engineering to increase carbon sink potential, and distinguishes and quantifies the contribution of climate and human activity factors to it, which is of great significance to the system management optimization scheme of terrestrial ecosystems and can effectively serve the national carbon neutral strategy.Graphical

Spatio-temporal evolution characteristics and simulation prediction of carbon storage: A case study in Sanjiangyuan Area, China

Understanding the relationship between land-use patterns and regional carbon storage, as well as predicting future land-use changes for regional carbon sink and emission management, are of immense significance. This study utilized land-use data from 1990, 2000, 2010, and 2020, as well as the InVEST model, to evaluate the spatiotemporal evolution of carbon storage in the Sanjiangyuan area over the past three decades. Furthermore, predictions for carbon storage in 2035 were presented using the PLUS model. The findings revealed the following key results: (1) the land types in the Sanjiangyuan area are mainly low cover grassland, medium cover grassland and unused land, among which unused land decreased significantly from 1990 to 2020, and the area of low cover grassland and wetland increased, which is the main reason for the increase of carbon storage. (2) Climatic-environmental and social-economic factors jointly influenced the land-use change in the Sanjiangyuan area. Except for the three types of grassland, the expansion of other land types was mainly influenced by climatic and environmental factors. (3) During 1990–2020, carbon storage in the source region of Sanjiangyuan area showed an overall upward trend, with a total increase of 39.97 × 107 t, and land-use change had a positive potential impact on carbon storage as a whole. (4) Under the natural change scenario, both carbon storage and regional carbon density increased in the simulation of 2035, and the potential impact of land-use change on carbon storage is positive. On this basis, the paper puts some suggestions forward to improve the carbon storage capacity of the Sanjiangyuan area in the future. This study provides valuable scientific insights for land-use management decision-making and promotes sustainable development of carbon storage functions in this region.

The spatial response of carbon storage to territorial space composition and landscape pattern changes: A case study of the Fujian Delta urban agglomeration, China.

Understanding the impact mechanisms of territorial space composition and landscape pattern changes on carbon storage is critical to balance the development and utilization of territorial space and the conservation of the ecosystem. Thus, taking the Fujian Delta urban agglomeration (FDUA) of China as an example, this paper analyzed the impact of the transference in territorial space composition and the change in the coupling coordination degree (CCD) of landscape patterns on carbon storage based on the urban-rural gradient and grid scales. Results illustrated that the areas of agricultural, green, and blue spaces continued to decline, while the intensity of economic space expansion increased from 20.86 to 42.45% during 2000-2020. The grids with CCD change of landscape patterns declined mainly (accounting for 64.31%) in the first decade and rose mainly (accounting for 76.79%) in the second decade. The carbon loss of each under rural gradient was gradually serious. The percentage of grids with moderate and significant decrease in carbon storage escalated from 27.83 to 70.21%. Additionally, grids experiencing high carbon loss moved from the northeast coast to the southwest inland. The response of carbon storage change showed that the expansion of agricultural space occupied by economic space played a crucial role in the carbon loss in each urban-rural gradient. The carbon loss caused by supplementing agricultural space with green space increased from the urban to the field. Enhancing the CCD of landscape patterns can boost carbon storage, and the scattering expansion of economic space needs to be avoided. This paper provides a novel perspective to explore the spatial response of carbon storage change to the territorial space composition and landscape pattern evolution, which is important to optimize the territorial space pattern and improve the regional carbon sink capacity.

Bedrock regulated climatic controls on the interannual variation of land sink in South-West China karst through soil water availability

South-West China (SWC) is a pivotal region for global greening, recognized as having great carbon sink potential. Multiple evidence underscores the expanding contribution of SWC’s carbon sink to the global carbon sink enhancement. However, our understanding of carbon sink dynamics and the response to climate across bedrock remains limited. In this study, we investigated the divergence in trends in carbon sink across bedrocks, evaluating their respective contributions of bedrocks to the overall carbon sink in SWC. Additionally, we assessed the dominant climatic factors and examined how bedrocks shape the response of carbon sink to climate change. Our results revealed a notable increase in the regional carbon sink, with an average rate of 3.58 TgC/yr from 1981 to 2019. Continuous Carbonate Rocks (CCR) exhibited the highest increased rate of total carbon sequestration (1.57 TgC/yr), surpassing Discontinuous Carbonate Rocks (DCR) by threefold. Non-karst areas contributed the most to both the mean and interannual variations of the overall carbon sink, with CCR exerting the most contribution to the trends. Over time, the contribution of CCR to the overall carbon sink escalated, while the contributions of DCR and non-karst declined. All bedrocks displayed negative correlations between NEP and temperature, with DCR showing higher susceptibility. Non-karst areas experienced adverse impacts from vapor pressure deficit, while CCR benefited from positive soil moisture effects. Our findings implied that bedrock indeed played a critical role in the variations in NEP and the response of NEP to climate change. Bedrock regulated climatic controls on carbon sink through soil water availability as soil water availability is affected by the lithology of basement carbonate. This novel understanding emphasizes the necessity for tailored ecological restoration initiatives that consider the distinctive lithological features of the karst ecosystem, and holds significance for implementing ecologically sound projects in karst regions.

Spatial Distribution Patterns of Soil Organic Carbon in Karst Forests of the Lijiang River Basin and Its Driving Factors

The aim of this study was to explore the carbon storage potential of karst forest soils in the Lijiang River Basin, reveal the spatial pattern of soil organic carbon (SOC), investigate the contributions and pathways of each driving factor to the spatial distribution of soil organic carbon, and provide a scientific basis for assessing the carbon cycle function of karst forests in the region. We employed structural equation modeling (SEM) and correlation analysis to investigate the spatial distribution characteristics of forest soil organic carbon in different basin sections (upper, middle, and lower reaches) and soil layers at different depths of the Lijiang River. Additionally, the direct and indirect ratios of each factor were quantified. The results showed that the overall soil layer of karst forest soils in the Lijiang River Basin was shallow, and soil organic carbon was phenoconcentric. The distribution of soil organic carbon content in different watershed sections was upstream > downstream > midstream, and the distribution of readily oxidizable carbon (ROC) and dissolved organic carbon (DOC) was consistent, whereas the distribution of microbial biomass carbon (MBC) was upstream > midstream > downstream. The contribution of various biotic and abiotic factors to the spatial distribution of soil organic carbon in karst forests in the watershed was different, and their contributions were ranked in descending order as:soil physicochemical factors > soil organic carbon active fraction > sample elevation > sample species diversity, with the total effects of 1.148, 0.574, 0.284, and -0.013, respectively. Among them, the sample site elevation had only an indirect effect on soil organic carbon, and the soil organic carbon active fraction had only a direct effect on soil organic carbon. Among the driving factors, total soil nitrogen, soil oxidizable organic carbon, sample site species richness, and soil soluble organic carbon could be used as important predictors of soil organic carbon content in karst forests in the Lijiang River Basin. Therefore, it is necessary to establish an effective eco-environmental protection mechanism covering the whole Lijiang River Basin, to reduce and control the impact of anthropogenic disturbances (especially in the middle urban section of the Lijiang River Basin), and to enhance and protect the species diversity of karst forests in the basin in order to improve soil physicochemical properties, improve and enhance the content of the soil organic carbon active fraction, and enhance the soil organic carbon stocks of karst forests in the Lijiang River Basin through other effective ways, as well as to promote the enhancement of the regional forest carbon sink function.

Exploring the optimization of spatial patterns for carbon sequestration services based on multi-scenario land use/cover changes in the changchun-Jilin-Tumen region, China

Optimizing the spatial pattern of carbon sequestration services is essential for enhancing regional ecosystem carbon sink capacity and promoting carbon budget equilibrium. This study leveraged land use/cover changes (LUCC), meteorological, ecological, and socio-economic data, integrating the InVEST and PLUS models to quantitatively evaluate changes in carbon sequestration services within three 2035 scenarios: economic development (ED), ecological protection (EP), and natural development (ND). Furthermore, it incorporated a Bayesian belief network (BBN) with decision-making optimization capabilities to pinpoint areas necessitating the optimization of spatial patterns for carbon sequestration services. The research findings reveal: (1) Substantial impacts of land use/cover changes on carbon sequestration services, with the spatial distribution of carbon sequestration capacity closely linked to land use patterns. (2) Considerable variation in carbon storage levels across different Changchun-Jilin-Tumen scenarios, while their spatial distribution patterns remain generally consistent. Over time, a notable declining trend in carbon storage levels by 2035 compared to previous years is observed. Spatially, the eastern and central regions of the study area emerge as high-value carbon storage zones, with the northwestern region exhibiting lower carbon storage values. (3) The three scenarios categorize CSS into ecological conservation zones, ecological buffer zones, construction development zones, and arable land protection areas. Notably, the construction development zones in the western and northwestern parts of the study area urgently require optimization management. Undertaking spatial pattern optimization studies based on the current state of CSS will sustain their sustainable development and assist in future spatial planning, carbon neutrality goals, and ecological restoration in the Changchun-Jilin-Tumen region.

Evolution of spatial network structure for land-use carbon emissions and carbon balance zoning in Jiangxi Province: A social network analysis perspective

Exploring the spatial network structure of land-use carbon emissions (LUCE) and the carbon balance in developing regions is pivotal for climate change mitigation in these areas. Using socio-economic and land-use data from 2000 to 2020, this study focused on Jiangxi Province as a representative case to elucidate the spatial network structure of LUCE and conduct carbon balance zoning. The primary findings were as follows: (1) The LUCE distribution in Jiangxi Province demonstrated a spatial pattern with high values in the northwest and low values in the southeast. An increasing trend was observed in the total amount of LUCE. Furthermore, there were evident regional differences in the Ecological Support Coefficient (ESC), indicating a weakening regional carbon sink capacity. (2) The spatial network structure of LUCE was intricate but stable. Although the gravitational interactions of LUCE between cities have intensified, overall network connectivity remained moderately correlated, indicating a prominent regional development imbalance. (3) There was a pronounced “core-periphery” structure in the LUCE spatial correlation network. Northern Jiangxi was the “core” of the network, taking an “initiator” role, whereas most cities in southern Jiangxi played a “passive” role, and resided at the “periphery” of the network. The inter-regional LUCE network exhibited pronounced spatial spillover, with inter-block correlations surpassing those within blocks. (4) By leveraging empirical data and spatial metrics, we categorized Jiangxi Province into five distinct carbon balance zoning types and subsequently proposed land-use optimization strategies. From the perspective of social network analysis (SNA), this study offers methodological insights into low-carbon development and synergistic emission reduction in developing regions.

Driving model of land use change on the evolution of carbon stock: a case study of Chongqing, China.

Terrestrialecosystems are significant carbon sinks and are crucial for understanding the regional and global carbon cycles, energy flow, and climate change. As land use change is a significant process affecting ecosystem carbon stocks and striving for land degradation neutrality (LDN), studying it is essential for comprehending the evolution of regional carbon sink functions and achieving sustainable development goals. The drastically diverse land use patterns in each of the study area's regions resulted in significant differences in carbon stock. This study explores the evolution traits of carbon stocks based on land use data and their driving mechanisms in Chongqing during the past 30 years by using spatial analysis, the InVEST model, and geographic probes. The results demonstrate that from 1990 to 2020, land degradation in Chongqing was made worse by the demand for land for construction land, but the strategy of converting cropland back to forests raised the carbon stock of forest land. The overall result is a decrease in total carbon stocks of 5.1078 Tg or 1.5%. The main pathway for carbon loss pathway in the evolution of carbon stock is the conversion of cropland to construction land, and the primary carbon compensation pathway is the conversion of grassland and cropland to forest land, with a spatial distribution characterized by "higher in the whole area and obvious local differences." The land use intensity index has the most significant influence on the evolution of carbon stock. Moreover, the interaction of pairwise factors played a more important role in affecting the evolution of carbon stocks than did each factor individually. The case study in this paper shows that land use change is a significant driving mechanism for the evolution of carbon stock, and the development of a driving model theory is appropriate for deciphering the trajectory of carbon stock evolution and offering research suggestions for other regions.

Impact of land use change on regional carbon sink capacity: Evidence from Sanmenxia, China

Regional carbon sink fluctuations are largely influenced by land use. To enhance regional carbon sink and inform sustainable land management practices, it is critical to elucidate the influence of land use changes on carbon sink dynamics. Employing historical data on carbon sink in Sanmenxia region, this study analyzed alterations in land use and carbon sink between 2000 and 2020. The Future Land Use Simulation (FLUS) model was used to predict the impacts of land use type changes on regional carbon sink under three development scenarios (urban priority, cultivated land priority, and ecological priority).The result shows that:(1) From 2000 to 2020, cultivated land (with an increase of 3.26%) and construction land (with an increase of 22.85%) showed the most significant changes, with the main source of increase being grassland, while other land types showed little change. The southern part of the study area was mainly forest land and grassland, with higher carbon sink value than the northern part. (2) The simulation study of the three scenarios found that the development scenarios of ecological priority and cultivated land priority would be conducive to improving regional carbon sink value by 2040. Specifically, regional cropland, forest, and grassland were preserved due to the ecological red line and the restriction of basic farmland. This would increase the carbon sink value of the study area by 145 thousand tons and 171 thousand tons, respectively, compared with 2020. (3) The prediction results of the three development scenarios all showed that the carbon sink of the study area would decline first and then increase from 2020 to 2040. The carbon sink of the urban priority scenario would reach the lowest value in 2030, and the other development scenarios would reach the lowest value around 2028, and then increase significantly.