The achievement of harmonious advancement in high-standard ecological conservation and high-quality economic development within the Yangtze River Economic Belt (YREB) is of paramount significance for the comprehensive construction of a modern socialist strong country in China. This study concentrated on the 11 provinces and cities within China’s Yangtze River Economic Belt. A comprehensive index evaluation system was constructed. By employing the coupling coordination measurement model, grey relational model, and Panel Vector Autoregression (PVAR) model, this study measured and analyzed the coupling coordination degree and interactive relationship between the ecological environment and high-quality economic development of the Yangtze River Economic Belt from 2012 to 2022. The results indicated that: (1) the coordinated development level between the ecological environment and high-quality economic development in the YREB had undergone a phased evolution from "moderate maladjustment-basic coordination-moderate coordination," exhibiting an overall spatial differentiation pattern of "lower reaches of the Yangtze River > middle reaches of the Yangtze River > upper reaches of the Yangtze River." (1) By the year 2022, only Shanghai, Zhejiang, and Jiangsu had achieved a moderate coordination, while the remaining provinces and cities were all in a state of basic coordination. (3) The correlation between regional subsystems within the YREB and the coupling coordination degree of the two systems showed a relatively balanced degree of association, with the correlation degree of each subsystem indicator generally exceeding 0.8, indicating a robust interactive relationship. (4) In the early development stage of the YREB, the ecological environment was significantly impacted, but subsequently recovered and stabilized over time. The short-term negative impact of the economy on the ecological environment gradually diminished. Accordingly, it was essential to implement measures such as targeted policies, environmental regulation improvements, and enhanced intra-regional cooperation to further promote the coordinated development of the ecological environment and economy in the YREB, to achieve the sustainability of regional development.

The achievement of green total factor productivity (TFP) growth is an important way for the Yangtze River Economic Belt (YREB) to practice green and low-carbon development and achieve high-quality development. This study took the measured green TFP of the YREB from 2005 to 2020 as the research object, and used the methods of spatial distribution map and standard deviation ellipse to explore the temporal and spatial evolution and agglomeration characteristics from the perspective of urban agglomeration. The driving factors of the spatial differentiation of green TFP were studied by means of geodetector. The results showed that: (1) From 2005 to 2020, the green TFP of the whole YREB, the middle reaches of the Yangtze River city cluster and the Chengdu-Chongqing city cluster showed a development trend of a first decline and then an increase. The Yangtze River Delta city cluster showed a development trend of a first growth and then a decline and then an increase. (2) The green TFP of the YREB showed a spatial pattern of "Yangtze River Delta urban Agglomeration > Chengdu-chongqing urban Agglomeration > Urban agglomeration in the middle reaches of the Yangtze River "and" Central City > Non-central city; (3) The green TFP of the Yangtze River Delta urban agglomerations and the middle reaches of the Yangtze River experienced an evolutionary process of "first decentralization, then agglomeration". The agglomeration development characteristics of the green TFP of the Chengdu-Chongqing urban agglomerations were not obvious, but there was an obvious trend of migration to the east, and the central cities had a greater impact on the distribution pattern of green TFP. (4) The single factor detection results showed that urban development level, technological innovation and environmental regulation level were the core driving factors of the spatial differentiation of green TFP. The interactive detection results showed that the interaction of driving factors was greater than that of single factors, and the interaction of digitalization level and environmental regulation level in 2020 had the strongest interpretation of green TFP.

Identifying the evolution of spatial structure is of great significance in promoting regional high-quality development and synergistic development. Based on the perspective of "relationship", we investigated the evolution of the network structure of urban links in the Yangtze River Delta (YRD) region from 2015 to 2022 in terms of "flow-direction-flow-point characteristics-community structure". The influencing factors were explored using the modified gravitational model and the method of social network analysis. The results showed that: ①The pattern of the strength of urban spatial links had changed from "one big, three small" to "multiple blossoms"; The first link in the region formed a spatially multi-centered and relatively closed territorial system, and the direction of the first link did not have a clear trend of concentration. ② From the perspective of the overall characteristics of the YRD region, the spatial connection between cities had increased. The spatial structure was solid, and the two-way interaction was strong; From the perspective of the individual characteristics, the degree of urban centrality had changed from unbalanced to balanced, and the network had gradually flattened. ③In 2015-2019, the core area undertook the radiation-driven function in the region, and there were more cities in the role of "brokers";  In 2019-2022, the "broker" segment disappeared, and the former core region changed to a "two-way spillover" role. ④Geographic proximity had a stable positive effect on the association network, and the level of market environment and scientific and technological innovation had also shown a positive spillover in recent years; The level of economy showed a stable negative significant effect, and the level of information infrastructure showed a negative significant effect in recent years; The administrative relationship was no longer obvious, which indicated that cities were breaking down the boundaries of the provinces to create associations.

Understanding the spatiotemporal differentiation characteristics and formation mechanisms of space evolution of aquatic ecology in the urban agglomerations of the middle reaches of the Yangtze River is crucial for implementing land use control and integrating aquatic ecological space governance into the territorial spatial planning system. This study constructed a classification system for aquatic ecological space, tailored to the current demands for spatial use regulation in territorial spatial planning. Using a spatial transfer matrix and topographic position analysis, the study delineated the spatiotemporal evolution of aquatic ecological space from the dual perspectives of "scale-topography." Additionally, a Partial Least Squares Structural Equation Model (PLS-SEM) was introduced to quantitatively analyze the mechanisms underlying the aquatic ecological space patterns in the study area from 2000 to 2020. The results revealed that: 1) Over the past two decades, the aquatic ecological space had diminished by 1 614.26  km2, a decrease of 7.63%, with significant reductions in Hubei and Hunan provinces, and a slight increase in Jiangxi province. The dynamic conversion between "agricultural space and aquatic ecological space" was particularly pronounced, with the most intense transitions observed in the Jianghan and Two Lakes Plains; 2) From a topographic gradient perspective, the loss and expansion of aquatic ecological space predominantly occurred in low topographic regions, with an overall trend of shifting toward higher elevations; 3) The PLS-SEM effectively elucidated the relationships between aquatic ecological space and multiple influencing factors, even with small sample sizes and non-normally distributed spatial data. The evolution of aquatic ecological space was significantly influenced by geomorphological foundations, road infrastructure development, and agricultural production activities. Population growth, social development, and economic and industrial expansion exerted indirect impacts through road infrastructure and agricultural production, while climatic and hydrological changes had a notable effect solely on the expansion of aquatic ecological space. This study provided theoretical support and data references for the quantitative analysis of the pattern-process-mechanism of aquatic ecological space under the context of territorial spatial planning in the urban agglomerations of the middle reaches of the Yangtze River.

 

Enhancing the comprehensive carrying capacity of urban agglomerations is a key task to realize high-quality development. Based on the panel data of 28 prefecture-level cities in the city cluster in the middle reaches of the Yangtze River from 2010 to 2021, this study comprehensively evaluated the spatio-temporal evolution characteristics of the comprehensive urban carrying capacity of the region by comprehensively applying the DPSIR framework and entropy-weighted TOPSIS methodology. Additionally, the obstacle factor model was used to diagnose the constraints. The study found that: (1) The overall comprehensive carrying capacity of the urban agglomeration in the middle reaches of the Yangtze River showed an upward trend, although the growth rates varied; (2) In terms of spatial distribution, the comprehensive carrying capacity of the urban agglomeration had evolved from low-level imbalance to high-level imbalance, presenting a spatial differentiation pattern of "higher in center city"; (3) The driving force and response systems contributed significantly to the comprehensive carrying capacity of cities, while the pressure and state systems had a relatively small effect; (4) The obstacle factors affecting the comprehensive carrying capacity of cities in the urban agglomeration included innovation capacity, infrastructure construction, education, and public cultural service levels. The results of this study provided a scientific basis and guidance for the formulation of sustainable development policies for the urban agglomeration of the middle reaches of the Yangtze River and similar urban agglomerations.

This study conducted monitoring in the Jianli section of the middle reaches of the Yangtze River, for 2019 to 2022. By comparing the changes of species composition, resources and diversity of fish eggs and larvae before and after the fishing ban, this study preliminarily evaluated the effectiveness of the fishing ban in restoring fishery resources in Jianli section of the middle Yangtze River. The results showed that little difference was identified in the number of species for a total of 27 types of fish eggs. The common species included white amur bream, Hemiculter bleekeri, redeye carp and silver carp. However, the proportion of small fish decreased, while the proportion of medium and large fish increased. The amount of fish eggs showed a certain downward trend from 2019 to 2022. Diversity index analysis showed that the Margalef richness index (d) of fish eggs decreased after the fishing ban, but the Shannon-Wiener species diversity index (H), Pielou species evenness index (J), and Simpson dominance index (D) increased. A total of 45 types of larvae were monitored, with 39 types collected in 2022, which was the highest in the monitoring period. After the fishing ban, the larval size increased significantly, that exceeded 120 billion for two consecutive years from 2021 to 2022. The proportion of small fish decreased, while the proportion of Four Major Chinese Carps, white amur bream and white knifebelly carps increased. The dominant species increased from four to ten, and white amur bream, silver carp, and yellowcheek carp returned as dominant species. The Margalef richness index (d), Shannon-Wiener species diversity index (H), Pielou species evenness index (J), and Simpson dominance index (D) of the larvae all showed a positive trend. These results indicated that the larvae resources in the middle reaches of the Yangtze River had significantly increased after the fishing ban, especially for the medium and the large fish. The fish community structure was also changing, which implied that the fishing ban policy had achieved preliminary outcomes in protecting the biodiversity of the Yangtze River. It is recommended that the enforcement of the fishing ban measures be strengthened.

Extreme climate change has a significant impact on the hydrological rhythm of lakes, which further affects the spatial and temporal characteristics of wetland hydrological connectivity (HC), and may promote or inhibit the functional services of wetland ecosystems. The modified nearest water source distance method was used to characterize the HC of Poyang Lake. This method was defined as the nearest distance from any point of land and water to the water-land boundary. The spatial and temporal characteristics of HC and the influence of water level in Poyang Lake wetland were studied using remote sensing images during 2020 to 2022. The spatial differences of HC in the dish-shaped sub-lakes wetland and its impact on the protection of migratory birds were further revealed. The results found that the change of HC was controlled by the lake water level, and the seasonal characteristics of HC in Poyang Lake wetland were obvious. It was indicated that the HC followed a pattern of changing from weak to strong and then to weak, in response to the seasonal transition of lake water level of rising-flooding-falling. The interannual variation of HC was closely related to the lake water regime. Moreover, the interannual variation of HC in the rising and dry seasons was small, while the interannual variation of HC in the flooding and falling seasons was significant. The HC of Poyang Lake wetland demonstrated a spatial pattern of the strongest value in the northern lake area, followed by the value in the northeastern lake area. A larger variability was shown in the southern lake area. Affected by geographical location, topographic characteristics, human activities and lake water conditions, the clustering characteristics of HC for the dish-shaped sub-lakes wetland were obvious. The results confirmed that a moderate HC and large sub-lake area were conducive to the habitat of wintering migratory birds. The three types of dish-shaped lakes represented by Dahuchi Lake, Shahu Lake and Banghu Lake were the hot spots for wintering migratory birds. This study demonstrated that the modified nearest water source distance method was suitable for HC analysis of lake wetlands, based on remote sensing. The research results provided an important reference for the protection of wintering migratory birds in Poyang Lake and the approaches of assessing HC in floodplain wetlands in other areas.

Under the background of global climate change, the runoff of the four major river systems of Dongting Lake has changed significantly, which in turn leads to alterations in the water resources and hydrological elements of the  Lake basin. In order to explore the change trend of the runoff of the four major river systems into Dongting Lake in the future, the SWAT model of the Dongting Lake basin was established. By controlling the dual variables of temperature and precipitation, 14 different climate change scenarios were set up. calculations and analyses were conducted to assess the impact of different temperature and precipitation change scenarios on the runoff of the four major water systems into Dongting Lake. The results showed that: (1) In both annual and monthly scales, all of the simulation results of Nash efficiency coefficient and correlation coefficient for the calibration and validation periods were greater than the qualified standard, and nearly 2/3 of the simulation results met the excellent standard. The monthly simulation results of the runoff were better than those at an annual scale. The results indicated that the established SWAT model could be well applied to the simulation and prediction of the runoff. (2) It was predicted that the annual and monthly runoffs would vary significantly. The runoff increased significantly with an increased precipitation, but decreased slightly with a rising temperature. This suggested that precipitation changes had a greater impact on runoff than temperature changes. This study provided reference and data support for assessing the impact of future climate changes in hydrology and water resources of the Dongting Lake Basin and for a rational formulation of the basin development strategies.

Establishing a sound multi-level ecological protection compensation mechanism that reflects the value of carbon sinks is an urgent need for China to implement its “dual-carbon” strategy in the new era. Based on the fiscal vertical and horizontal perspective, this study constructed a cross-regional “double vertical and double horizontal” carbon ecological compensation payment framework, based on the carbon sink value spillovers. This empirical research was carried out at the provincial and county levels. The results showed that: (1) during the period of 2010-2020, the value of the carbon sinks in the YREB and Hubei Province was always in surplus. The amount of surplus increased annually, but there was a significant difference in the surplus status within the study region. (2) From 2010 to 2020, the total amount of vertical and horizontal carbon ecological compensation payments that the YREB eventually received would be 71.967 billion yuan, 82.735 billion yuan and 92.081 billion yuan, respectively. Implementing financial allocation according to the contribution of carbon sink value spillover, the average annual carbon eco-compensation payout for each surplus province would range from 1.422 billion to 32.016 billion yuan. The total amount of vertical and horizontal carbon ecological compensation payments available at the county level in Hubei Province was 4.198 billion yuan, 6.184 billion yuan, and 8.482 billion yuan, respectively, with surplus counties receiving an average annual carbon ecological compensation payout of 0.02 to 291 million yuan. The difference in carbon ecological compensation payments between provinces and counties was found to be obvious. (3) Comparing the carbon ecological compensation standard measured under the compensation payment framework with the GDP and fiscal revenues of each level of government, it was indicated that the compensation standard would not result in "wipeouts" or "windfalls" in the paying and receiving areas, which helped to incentivize the receiving areas to protect the carbon sinks. Moreover, the compensation payment framework needed to be further constructed from the legal guarantee system, technical guarantee system, social security system and organizational guarantee system for building a long-term mechanism, in order to ensure the regular implementation of the constructed “double vertical and double horizontal” carbon eco-compensation payment system.

Building a scientific and reasonable ecological security pattern under climate change is a win-win way to achieve the sustainable development of regional socio-ecological composite system. This is of great significance to reduce climate risk and improve ecological stability. Taking Jiangsu Province as the study area, we identified the ecological source areas in terms of the suitability of ecological factors and the naturalness of ecosystems. The resistance surfaces were constructed, based on the relationship between the vulnerability to climate change and the ecological security pattern. The ecological corridors were identified using the least resistance model and the gravity model. The ecological security pattern were constructed and evaluated in Jiangsu Province, and an optimal restoration pathway was proposed. The results showed that the ecological source area of Jiangsu Province was 10,423.20km2, which accounted for 9.72% of the total land area of the province. The ecological source area was mainly distributed in rivers and lakes, coastal wetlands in the east and hilly and mountainous areas in the south-west. The vulnerability index to climate change ranged from 0.226-0.522, with a spatial pattern of ‘gradient-type elevation from the middle to the north of Jiangsu Province’, and the overall pattern was characterized by a ‘gradient-type elevation’. The vulnerability index demonstrated a spatial pattern of ‘gradient rising from central Jiangsu to southern Jiangsu and northern Jiangsu’. The overall vulnerability was low. The distribution of high vulnerability areas was mainly concentrated in the ecologically sensitive areas in hilly areas. A total of 35 ecological corridors with a total length of 2,448.66km had been extracted, which  presented a spatial pattern of ‘sparse in the north and dense in the south, and sparse in the east and dense in the west’. The overall ecological security pattern was ‘two vertical and four horizontal’. The ecological network was relatively imperfect, and the connectivity of ecological nodes was low. It was necessary to strengthen the construction of important ecological corridors. The study aimed to provide new perspectives for the construction of ecological security pattern and offer reference for the response to climate change to ensure regional ecological security

The study of carbon emission effects of wetland changes plays an important role in achieving carbon peak and carbon neutrality strategic goals. Taking Jiangsu Province as the research area, wetland information from the past 30 years was extracted. A carbon emission effect model for wetland changes in Jiangsu Province was constructed. The spatiotemporal pattern evolution characteristics of carbon emission effects in Jiangsu Province were analyzed. The results indicated: (1) Utilization of Landsat images provided by the GEE platform and the application of random forest algorithm enabled a rapid and accurate extraction of wetland information in Jiangsu Province. From 1990 to 2020, the total area of wetlands decreased from 1,919,310.03hm2 to 1,659,403.89hm2, a decrease of 13.54%; (2) Wetlands in Jiangsu Province exhibited a carbon sink status, with the average annual carbon sink decreasing from 970,622.32t in 1990 to 782,965.05t in 2020. The spatial distribution of carbon sinks showed a stable "southeast-northwest" pattern; (3) Over the past 30 years, the carbon emission effects of wetland change in Jiangsu Province amounted to 6,525,507.60t, with significant spatiotemporal heterogeneity characteristics. The carbon sources caused by wetland changes amounted to 7,117,328.91t, which were mainly resulted from the conversion of various types of wetlands to construction land. The carbon sinks caused by wetland changes amounted to 591,821.31t, mainly resulting from the conversion of construction land to various types of wetlands and the conversion of various types of wetlands to cropland. The research results provided data and theoretical support for the formulation of wetland protection policies and the achievement of dual carbon goals in Jiangsu Province.

The channel-sandbar system (CSS) is a common geomorphic combination of rivers, and its development and evolution may pose a threat to safety of navigation, water-related engineering, and flood control. The evolution of CSS involves both subaerial and subaqueous parts. Accurately calculating the amount of topographic change remains a challenge in geomorphology. This study took the CSS of Zhangjiazhou reach of the Yangtze River as an example. The joint changes in the volume of subaerial sandbars and subaqueous channel-sandbars were considered. Based on navigation reference plane and the measured water level at hydrological stations, remote sensing images and navigation maps were corrected to a unified elevation reference. An integrated digital elevation model (DEM) for the evolution of CSS volume was developed. The results indicated that this method could efficiently calculate the volume changes of the CSS. From 1993 to 2019, the changes of CSS in the study area was indicated as erosion (12.85 × 106m3 in 1993-2008), siltation (8.14 × 106m3 in 2008-2013), and siltation (15.72 × 106m3 in 2013-2019). Overall, the volume of the CSS in the study area increased by 11.77 × 106m3 during 1993-2019, which was equivalent to 14.12 × 106 t of sediment deposition, using a sediment bulk density of 1.2 t/m3.

Understanding the temporal and spatial distribution of organic carbon burial in shallow lake sediments and the corresponding influencing factors is of great significance for an improved understanding of the process of carbon burial and a correct evaluation of the role in the regional/global carbon cycle. A study was conducted in this paper based on the sediment age sequence established by the 210Pbex-239+240Pu composite dating method. The sediment core samples were collected in the east and west parts of Lake Chaohu. The total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP), the ratio of C/N, normal trace elements and grain size in sediments were analyzed. The results showed that the sedimentation rate and the organic carbon burial rate in Lake Chaohu ranged from 0.19~0.90 g cm-2 a-1 and 16.6 ~ 71.2 gC m-2 a-1, respectively. They indicated a trend of first decreasing and then increasing in the past 70 years. The rates were higher in the eastern lake than those in the western lake. Organic carbon in sediments in both east and west parts of Lake Chaohu was mainly endogenous in the past 70 years. The faster organic carbon burial rate in the eastern lake was mainly attributed to the faster sediment deposition rate and the deeper water body, which hindered the decomposition and mineralization of organic carbon in the sediments. While in the western lake, the disturbance of lake bottom mud caused by intense human activities and the nature of algal organic matter itself promoted the degradation and mineralization of organic carbon during sedimentation and burial, which affected the effective burial of organic carbon in the sediments. In addition, factors of climate change and human activities including the warming of the basin, the rapid economic development, the increase of population as well as the increase of agricultural fertilizer application had positive effects on the organic carbon burial in Lake Chaohu during the past 70 years.

Zigui County is a key area of biodiversity in the Yangtze River Basin and an important ecological barrier in the Three Gorges Reservoir area. Based on the field investigation of the species composition, distribution of harmful alien invasive plants, the risk assessment system of alien invasive plants was constructed. The analytic hierarchy process ( AHP ) according to the risk, current situation, harm and management difficulty was adopted in this study. The results showed that: ( 1 ) There were 68 species of alien invasive plants in Zigui County, belonging to 22 families and 45 genera. The species of Asteraceae, Amaranthaceae, Euphorbiaceae, Poaceae, Plantaginaceae and Fabaceae were the main families. The number of Asteraceae plants was up to 17 species, accounting for 25 % of the total species. ( 2 ) The number of invasive plant species was the largest in the range of 150-300 m above sea level, and they showed a downward trend with the increase of altitude. Maoping Town ( 51 species ) was a high outbreak area of invasive plants in various towns.( 3 ) The risk assessment of 68 alien invasive plants showed that the risk levels of Erigeron canadensis, Erigeron sumatrensis, Alternanthera philoxeroides, Erigeron annuus, Bidens pilosa and Symphyotrichum subulatum were high. It is suggested to strengthen the prevention and control of the spread of high-risk invasive plants such as Erigeron canadensis. A dynamic monitoring of the potential hazards of low-risk invasive plants was essential, to provide scientific basis for the management of alien invasive plants in Zigui County.

As an important carrier of rural revitalization and urban and rural leisure tourism, systematic analysis of the spatial distribution and accessibility of national-level villages is helpful to make rational use of rural resources and promote the comprehensive development of regional rural tourism. This study took five types of national-level villages in the Yangtze River Economic Belt, namely historical and cultural villages, traditional Chinese villages, ethnic minority characteristic villages, forest villages and key villages of rural tourism, as the research objects. The GIS spatial analysis method and mathematical statistics method were used to describe the spatial distribution and accessibility difference pattern of the villages from different spatial scales. The results showed that: (1) The spatial distribution types of the five types of villages all had typical agglomeration characteristic. The agglomeration intensity showed a sequence pattern of "traditional villages> ethnic villages > forest villages> historical and cultural villages> key rural tourism villages "; (2) The non-equilibrium degree of cities at the prefecture level and above in the five types of villages was higher than that at the provincial level, and the balance degree of quantity distribution was poor; (3) The spatial accessibility of the five types of villages was significantly differentiated. The internal differences were prominent, except for the accessibility of ethnic minority characteristic villages, which was "strong in the west and weak in the east". The accessibility of the other four characteristic villages showed a spatial pattern of "high in the east and low in the west"; (4) The accessibility of county units in five types of villages was affected; (5) Under the case of one-day, two-day, three-day, five-day and seven-day tours, the cities with daily accessibility advantages were identified as Hangzhou, Nanchang, Nanchang, Guizhou and Guizhou

In the context of the Yangtze River protection, the agricultural carbon emission reduction in the Yangtze River Economic Belt is an important support to achieve the goal of "dual carbon goals". By analyzing the influencing factors of agricultural carbon emission in the Yangtze River Economic Belt, a dynamic model of agricultural carbon emission system was established. A variety of scenarios were set up to simulate and predict the peak time, peak value and emission reduction effect of agricultural carbon emission intensity in the upper, middle and lower reaches. The results showed that: (1) Under the baseline scenario, the upper reaches are expected to reach the peak in 2032, and the middle reaches are expected to reach the peak in 2030. (2) The coordinated development scenario has the most significant effect on agricultural carbon emission reduction in all regions. The peak time of the upstream region, the middle region and the downstream region can be advanced to 2028, 2026 and 2025, respectively. Agricultural carbon emission intensity can be reduced by 13.84%、19.22%、15.83%, respectively, compared with the baseline scenario. (3) Under the single policy scenario, digital capital support has the best effect on agricultural carbon emission reduction in the upstream region, while environmental pollution control is the focus of agricultural carbon emission reduction in the middle region and the downstream region

The carbon metabolism system of cultivated land involves a large-scale, high-frequency carbon budget, which profoundly impacts the land-use carbon cycle. In the context of carbon neutrality goals, studying the characteristics of change in carbon metabolism density of cultivated land and the corresponding influencing factors can help expand our understanding of carbon metabolism. This study may provide a scientific basis for the sustainable development of cultivated land and land-use carbon reduction. Therefore, this study took Jiangsu Province as an example, and analyzed the characteristics of change in carbon metabolic density of cultivated land from 2000 to 2020. The metabolism density analysis from ENA was performed, and the primary drivers affecting carbon metabolism were identified. The spatial autocorrelation and geographically weighted regression models were used in this study. Our research revealed the following key findings: (1) The average carbon metabolism density of cultivated land in Jiangsu Province from 2000 to 2020 was 3336.06 t/km2, and the overall trend of carbon metabolism density of cultivated land showed a noticeable increase. (2) The spatial variation of carbon metabolism density was evident, with higher carbon metabolism density in economically underdeveloped areas and lower carbon metabolism density in economically developed areas. (3) The carbon metabolism density demonstrated a significant positive spatial correlation, characterized by spatial clustering of low-low or high-high values. This spatial positive correlation intensified over time. (4) Multiple factors influenced the change in the carbon metabolic density. The multiple cropping index and average annual precipitation had positive effects, while the average fertilizer use per mu and the level of fiscal support for agriculture had adverse effects. The average annual temperature exhibited a bidirectional regulatory effect, alternating between positive and negative influences. The carbon metabolism density effectively illuminated the complexity and dynamics of carbon cycles in cultivated land ecosystems, clearly illustrating how land use practices and management strategies dynamically modulated carbon inputs and outputs. Optimization of land management can effectively balance carbon inputs and outputs, which is crucial for achieving the dual carbon goals.