Cultivated Land Protection Research Articles

Analysis of the Evolution of the Policy of Linking the Increase and Decrease in Urban and Rural Construction Land in China Based on the Content Analysis Method

The policy of linking the increase and decrease in urban and rural construction land is a land policy that gradually forms and develops to solve the contradiction between “food and construction” under the background of urbanization in China. It is of great significance to the sustainable development of China’s social economy. In order to grasp the evolution of the policy of linking the increase and decrease in urban and rural construction land in China as a whole, this paper used the content analysis method to analyze the changes in the content of China’s urban−rural construction land increase/decrease linkage policy from different perspectives, such as the levels of policy promulgation and the types of policy promulgation. Firstly, 105 directly related policy texts were selected from a large amount of policy information and read in detail with this as a sample, and 11 keywords were extracted, which were “balance of occupation and compensation”, “clear property rights”, “reasonable planning”, “project area”, “turnover indicators”, “linkage procedure”, “voluntary principle”, “resettlement compensation”, “cultivated land protection”, “supervision and management”, and “capital finance and taxation”. Secondly, the policy text was coded to provide quantitative data on policy development. Finally, the trajectory of policy development was analyzed on the basis of the quantitative data on policy development. The results show that the existing policies were mostly issued in the form of notifications, management measures, implementation plans, working rules, and so on, involving the nature, principles, conditions, methods, procedures, capital finance and taxation, and circulation indicators of the linkage between the increase and decrease, but the policy effectiveness is low, and there is a lack of formal laws and regulations. Improving the legal status of the policy, changing the relationship between the government and the market, strengthening the protection of cultivated land, and reconstructing the income distribution mechanism will help to further improve the policy of linking the increase and decrease in urban and rural construction land.

Evolutionary characteristics of sloping cultivated land under functional diversification in mountain areas: A case of Fengjie County, China

With the rapid development of urbanization and industrialization, the rural functions in China's mountainous regions have tended to diversify, and the use of sloping cultivated land has also evolved. Exploring the coupling relationship between rural functional diversification and the evolution of sloping cultivated land is of great significance to the protection of cultivated land in mountainous areas and the sustainable development of villages. We constructed a theoretical framework to analyze the interaction between rural functional diversification and the evolution of sloping cultivated land and then verified it with Fengjie County, China. Our research results show that: the overall agricultural production function, industrial production function, leisure and tourism function, social security function, and ecological conservation function of Fengjie County continue to develop, and the diversification level of rural functions has been enhanced. The high density value areas of sloping cultivated land were more dispersed, and the area of sloping cultivated land showed a decreasing trend. The coupling coordination degree between rural functional diversification and the evolution of gentle sloping cultivated land showed a downward trend, and the ecological economic level of gentle sloping cultivated land decreased. The coupling coordination value with steep sloping cultivated land and sharp steep sloping cultivated land showed a firstly decreasing and then increasing trend, and the ecological economic level of the two kinds of cultivated land increased. The study area can be summarized into four coupling modes and different development strategies should be adopted for different coupling modes. These research methods and findings can provide a reference value for the optimal utilization of sloping cultivated land resources in other mountainous areas.

Spatiotemporally Mapping Non-Grain Production of Winter Wheat Using a Developed Auto-Generating Sample Algorithm on Google Earth Engine

Spatiotemporally mapping winter wheat is imperative for informing and shaping global food security policies. Traditional mapping methods heavily rely on sufficient and reliable samples obtained through labor-intensive fieldwork and manual sample collection. However, these methods are time-consuming, costly, and lack timely and continuous data collection. To address these challenges and fully leverage remote sensing big data and cloud computing platforms like Google Earth Engine (GEE), this paper developed an algorithm for Auto-Generating Winter Wheat Samples for mapping (AGWWS). The AGWWS utilizes historical samples to determine the optimal migration threshold by measuring Spectral Angle Distance (SAD), Euclidean Distance (ED), and Near-Infrared band Difference Index (NIRDI). This facilitates the auto-generation of winter wheat sample sets for the years 2000, 2005, 2010, 2015, and 2021. Approximately two-thirds of the samples were allocated for training, with the remaining one-third used for validating the mapping method, employing the One-Class Support Vector Machine (OCSVM). The Huang–Huai–Hai (HHH) Plain, a major winter wheat production region, was selected to perform the algorithm and subsequent analysis on. Different combinations of the hyper-parameters, gamma and nu, of the OCSVM based on the Gaussian Radial Basis Function Kernel were tested for each year. Following correlation analysis between the winter wheat area derived from the generated maps and the national statistical dataset at the city level, the map with the highest corresponding R2 was chosen as the AGWWS map for each year (0.77, 0.77, 0.80, 0.86, and 0.87 for 2000, 2005, 2010, 2015, and 2021, respectively). The AGWWS maps ultimately achieved an average Overall Accuracy of 81.65%. The study then explores the Non-Grain Production of Winter Wheat (NGPOWW) by analyzing winter wheat change maps from 2000–2005, 2005–2010, 2005–2010, and 2015–2021 in the HHH Plain. Despite an overall increase in the total planted area of winter wheat, the NGPOWW phenomena has led to concerning winter wheat planting marginalization. Compensatory winter wheat areas are notably situated in mountainous and suburban cultivated lands with low qualities. Consequently, despite the apparent expansion in planted areas, winter wheat production is anticipated to be adversely affected. The findings highlight the necessity for improved cultivated land protection policies monitoring the land quality of the compensation and setting strict quota limits on occupations.

Is marginalised cultivated land on the Tibetan Plateau suitable for production or ecology? An example from the northeastern Tibetan Plateau

AbstractIn the ecologically fragile alpine area of the Tibetan Plateau, some marginalised cultivated lands have more serious conflicts related to agricultural production and ecological protection than others; thus, it is of practical significance to explore the rational use of marginalised cultivated lands. In this study, Xining City and Haidong City in the northeastern part of the Tibetan Plateau were taken as the study area. Marginalised cultivated land was identified, and the vegetation photosynthesis model was used to evaluate its production function. Ecological function was evaluated in terms of soil retention, landscape connectivity and habitat maintenance. The rational use pathways of marginalised cultivated land were derived through statistical analysis and aggregation model analysis. The results showed that there were 183,489.19 ha of marginalised cultivated land in the study area; the average value of production function of marginalised cultivated land was approximately 70% of that of nonmarginalised cultivated land, and its various ecological functions reached 93.64%–117.98% of that of nonmarginalised cultivated land. In general, the distribution of production functions decreases from northwest to southeast, and the ecological functions are high in the middle and low in the surroundings. A comprehensive analysis of the production and ecological functions of marginalised cultivated land can provide a reference basis for the rational formulation of cultivated land protection policies and ecological protection policies.

Understanding the distribution patterns and underlying mechanisms of non-grain use of cultivated land in rural China

How to control the non-grain use of cultivated land (NGUCL) for the simultaneous development of food security, rural revitalization, and ecological protection has been a major topic of global concern. However, insufficient understanding of the pattern and its underlying mechanisms has posed major challenges for related policy-making. To bridge this gap, this study established a theoretical framework for NGUCL analysis and employed quantitative methods to reveal the NGUCL pattern and its mechanisms. The key finding is that there was a core–edge model of NGUCL distribution pattern from the suburbs to the remote suburbs; this was determined by a policy–market–site coupling mechanism and non-grain market location enhanced mechanism. The foremost contribution of this study is that it presents a global understanding of the core–edge model using a coexisting pattern analysis on NGUCL from the suburbs to the remote suburbs based on our understanding of non-grain growing behaviors. To strengthen control of NGUCL, we propose implementing regionally differentiated policies for cultivated land protection together with spatial planning for crop growing. We argue that the key to policy improvement is to maximize agricultural labor productivity in accordance with market demand. The findings and suggestions of this study are significant for China and other regions to promote NGUCL control and cultivated land protection.

Evolution and Driving Forces of Ecological Service Value in Anhui Based on Landsat Land Use and Land Cover Change

The main challenge in protecting ecosystems and improving the supply of ecosystem services is to quantify the ecological services value (ESV). However, the detailed spatiotemporal changes, sensitivity, spatial autocorrelation, and driving mechanisms of ESV are not clear in rapidly developing regions, particularly subsidence, floods, landslides, and the rapid urban development of Anhui province, China. In this paper, the ecological service value of Anhui Province in the past 30 years was calculated using the improved equivalent factor assessment method from satellite remote sensing such as Landsat. The spatiotemporal evolution characteristics of ESV were analyzed and the driving mechanism of ESV changes was studied using Geodetector. Finally, The GeoSOS-FLUS model was selected to predict the ecosystem service value until 2030 with three scenarios: business as usual (BAU), ecological protection (EP), and cultivated land protection (CLP). The main results were obtained: (1) the ESV in Anhui Province continued to decrease by 2.045 billion yuan (−6.03%) from 1990 to 2020. The top two contributors were the forest land, followed by water area. (2) The global Moran’s I of ESV at the landform subdivision, county, town, and grid scales in Anhui Province were −0.157, 0.321, 0.357 and 0.759, respectively. (3) The order of influence degree of driving factors was: precipitation (F4), distance to intercity road (F9), net primary productivity, NPP (F6), distance to urban road (F8), population (F13), temperature (F5), aspect (F3), distance to settlement (F11), slope (F2), elevation (F1), GDP (F14), distance to water (F12), distance to railway (F10), and soil erosion (F7). (4) In 2030, the simulated ESV under the three scenarios will decrease to varying degrees. Compared with 2020, the ESV of the three scenarios will decrease successively as follows: BAU (−1.358 billion yuan), EP (−0.248 billion yuan), and CLP (−1.139 billion yuan).

Spatial and Temporal Evolution and Prediction of Carbon Storage in Kunming City Based on InVEST and CA-Markov Model

Land use/cover change is an important driving factor for carbon stock changes in terrestrial ecosystems and affects the carbon cycle of the whole ecosystem. Taking Kunming City as a case study, based on the modified carbon density coefficient, this study analyzed the spatio-temporal characteristics of carbon storage changes in the terrestrial ecosystem under different land use scenarios from 2000 to 2020 and "three-line" constraints by coupling the carbon storage module of the InVEST model and CA-Markov model. The results showed that:① cultivated land, forest land, and grassland were the main types of land use in Kunming City, and land use transfer also occurred among the three types. ② From 2000 to 2020, the overall carbon storage in Kunming City was low in the south and high in the north, and the carbon storage decreased yearly with a cumulative loss of 5.27×106 t. The degradation of forest land and grassland was the main reason for the decrease in carbon storage. ③ From 2020 to 2030, the carbon storage of the four scenarios should decrease, and the decline in carbon storage in the inertia development scenario was the most obvious, which was mainly caused by the rapid expansion of construction land. The cultivated land protection scenario effectively slowed down the reduction in carbon storage compared with the inertia development scenario. The ecological protection scenario could enhance the carbon sequestration capacity of the study area, with carbon storage reaching 262.49×106 t, but could not effectively control the reduction in cultivated land area. The scenario of preventing urban expansion effectively inhibited the disorderly expansion of construction land and indirectly prevented further reduction in carbon storage. Therefore, the cultivated land protection scenario, ecological protection scenario, and urban expansion prevention scenario can be considered comprehensively in the study area, which could not only increase the carbon sink space of the study area but also ensure food and ecological security.

Carbon Storage Assessment under Mangrove Restoration of Dongzhai Harbor in Hainan Island, China

Mangrove restoration is recognized as an effective strategy for enhancing the carbon storage capacity of natural ecosystems, advancing toward the “carbon neutrality” goal. The carbon storage effects of ecological restoration efforts remain insufficiently understood as previous studies have focused on carbon storage dynamics in ecosystems, yet the specific impacts of targeted mangrove restoration are less explored. This study utilizes multi-temporal remote sensing data and actual restoration data from Dongzhai Harbor Hainan Island to identify the mangrove wetland coverage and quantify the spatiotemporal evolution of carbon storage under various restoration efforts using the InVEST model. Additionally, we employed the PLUS model to simulate and compare carbon storage potential under multiple development goals. The findings reveal the following: (a) Mangrove restoration significantly increased the area of land with high carbon sink capability, resulting in a regional carbon storage increase of 210,001.68 tons from 2015 to 2021, with 97% of this increase attributable to ecological restoration. (b) Mangrove coverage is crucial for regional carbon storage, with an average of 443 tons of carbon stored per hectare. Decreases in carbon storage occurred mainly during the conversion of mangroves to aquaculture, and forests/agriculture to residential areas. Increases in carbon storage were seen in the reverse transitions. (c) Comparing the scenarios focused solely on mangrove protection with cultivated land protection, the carbon storage in Dongzhai Harbor is projected to reach its maximum by 2045 under the carbon storage priority scenario. Our findings build a scientific foundation for formulating effective mangrove conservation and restoration strategies.

Impact of agricultural technology promotion on the sustainable protection of cultivated land by grain growers: Mediation effect based on expectation confirmation

Impact of agricultural technology promotion on the sustainable protection of cultivated land by grain growers: Mediation effect based on expectation confirmation

Research on Legal Issues of Ecological Protection of Cultivated Land in China under the Background of Food Security

A sound legal system for ecological protection of cultivated land plays an important role in ensuring ecological protection of cultivated land and food security. The legalization of ecological governance will inevitably become an important governance approach in China in the future. With the development of agriculture and the further expansion of urban scale in China, the sustained high-intensity utilization of arable land resources has led to severe degradation, quality decline, ecological imbalance, and insufficient reserve resources. The sustainable utilization of arable land resources is facing severe challenges. This requires stricter requirements for farmland protection work, clear implementation of hard measures for farmland protection, and adherence to the strictest farmland protection system while comprehensively promoting the rule of law and ensuring food security. By exploring the problems in China’s legal system for ecological protection of arable land, starting from timely strengthening the systematic legislation for ecological protection of arable land, improving the legal mechanism for ecological protection of arable land, improving legal measures for ecological control of arable land, and improving the legal protection system for pollution prevention and control of arable land, we aim to improve the legal system for ecological protection of arable land, promote the sustainable utilization of arable land resources, and ensure national food security.

Measurement of cultivated land ecosystem resilience in black soil region of Northeast China under the background of cultivated land protection policy in China: Case study of Qiqihar City

Scientific understanding and measurement of cultivated ecosystem resilience is crucial for the protection of cultivated land represented by black soil and the sustainable development of cultivated land ecosystem. In this study, we took Qiqihar, a typical black soil region, as the study area and divided the cultivated land ecosystem into two subsystems, black soil ecology and human socioeconomic. And we constructed a “policy background - generation process - system composition” measurement element screening model (PGSM) to establish the subsystem index systems. Cultivated land ecosystem resilience in 2020 was measured by the Pressure-State-Response (PSR) model and the multiscale fusion model. The results showed that the resilience of the black soil ecological subsystem (54.27) in Qiqihar is higher than that of the socioeconomic subsystem (49.01), and their spatial distribution trends were opposite. The overall resilience of cultivated land ecosystem was moderately low (51.64) but spatially heterogeneous. Cultivated land resource endowment and human activities pressure had the greatest impact on the subsystem. Socioeconomic input was the primary problem in regional resilience. Based on these findings, we made suggestions for cultivated land protection in black soil regions. This study contributes to the scientific and comprehensive measurement of the cultivated land ecosystem resilience and provides reference for sustainable management of black soil systems in China and globally.

Artificial-Intelligence-Enhanced Study on the Optimization of the Responsibility and Compensation Mechanism for Provincial Cultivated Land Retention from a Fairness Perspective

Research Objectives: Considering the complex challenges arising from urbanization, population growth, and the consequential strain on China’s cultivated land resources, we integrate insights from advanced artificial intelligence (AI) technology. The primary objective is to quantitatively assess the cultivated land-holding responsibility of local governments in China from a fairness perspective. Our aim is to integrate the cultivated land responsibility ownership amount into the compensation mechanism for cultivated land protection, thereby promoting fairness, cultivated land conservation, and sustainable agricultural development across Chinese provinces while ensuring efficient agricultural product distribution. Research Methodology: Beyond a traditional literature review and model analysis, we incorporated AI technology for data analysis and model optimization. Findings: ① The findings demonstrate a surplus in both food security and ecological security within cultivated land. ② In-depth analysis via AI revealed that the provinces with the largest surplus include Heilongjiang, Jilin, and Hubei. ③ With the precision provided by AI, we delineated the minimum value of the cultivated land responsibility ownership amount for each province. Eleven provinces met this criterion, primarily located in the northeast and central regions and including Yunnan in the west. ④ From a fairness perspective, coupled with AI insights, we established a compensation mechanism for cultivated land protection that is better suited to the Chinese context. Based on this mechanism, the national average compensation standard was calculated to be 26,900 CNY per hectare. The highest standards were observed in Shanghai, Beijing, and Jiangsu, while the lowest were in Shanxi, Heilongjiang, and Gansu.

Coordinated development of cultivated land use and ecological protection in cities along the main stream of the Yellow River in Henan Province, China

The protection and sustainable management of cultivated land are cornerstones of ensuring ecological balance. In implementing cultivated land protection policies, spatially defined land-use strategies can aid in the sustainable utilization of these land resources. Yet, recent agricultural activities have affected the water quality of the Yellow River and pose a significant challenge to the Yellow River basin. Many policy considerations have overlooked the ecosystem integrity. To address this oversight, we targeted cities bordering the main course of the Yellow River in Henan Province and constructed an ecological security pattern (ESP) defined by “five zones, one belt, multiple corridors, multiple points” to coordinated development cultivated land use and ecological protection. Ecological sources were identified via four ecosystem services (ESs) and the ordered weighted average (OWA) method. The ESP was built using the minimum cumulative resistance (MCR) model and circuit theory, while cultivated land protection and natural development scenarios were simulated using the FLUS model. The results showed that the cultivated land protection scene under ecological security pattern restriction (ESPR-CP) was beneficial to the ecological environment. Prior to enacting cultivated land protection measures, developments within priority conservation areas should be restricted. Cultivable areas should be at the forefront of stringent land protection policies. In addition, cultivated land situated along key ecological corridors and pinch points should improve in soil quality while prohibiting conversion to other types of land use, and the conversion of cultivated land in barriers to green space should be promoted further. This study provided a theoretical basis for how the government may enforce the cultivated land protection policy while promoting ecological protection, and it is also relevant to other areas located on both sides of the river.

Study on the Ecosystem Service Supply–Demand Relationship and Development Strategies in Mountains in Southwest China Based on Different Spatial Scales

Mountainous regions typically exhibit a strained relationship between humans and the land, with noticeable spatial differences in the supply and demand of ecosystem services (ESS and ESD, respectively). ESS and ESD display varying characteristics at different spatial scales. Research on ESS and ESD at multiple scales can aid regional development and efficient ecosystem management. However, the current research focuses on ESS and neglects the ES characteristic changes at different scales. This study concentrates on the Hengduan Mountain region in southwest China. It evaluated ESS and ESD, analyzed the spatial matching relationship, and proposed a corresponding development strategy. The results demonstrated four key findings. First, ESS displayed an inverse spatial distribution on the two scales and was lower in the north and higher in the south at the raster scale. Over the period 2000–2020, ESS exhibited a pattern of initial increase, followed by a decrease, albeit with varying spatial patterns. Changes in land use primarily drove these ESS changes. Second, ESD increased from northwest to southeast on both scales and showed a rising trend over time. Third, at the grid scale, the low supply and low demand (L-L) region is primarily situated in the northwestern part, and it is crucial to prevent grassland degradation and manage grazing intensity. The low supply and high demand (L-H) region is located in the southeast, where the protection of cultivated land, along with comprehensive control of rocky desertification and debris flow, should be prioritized. High supply and low demand (H-L) are found in the northern mountain area, where paying attention to soil erosion control is essential. For areas with high supply and high demand (H-H) types, efforts should be directed toward maintaining forest habitat integrity. Fourth, on the county scale, L-H types should focus on realizing the ecosystem service value and implementing ecological agriculture. H-L counties can appropriately develop economic activities. Simultaneously, ecological compensation should be conducted among counties.

Study of the Morphological Characteristics of Cultivated Land in Semiarid Sandy Areas

The unique natural geographical conditions and land use patterns in semiarid sandy areas have resulted in a distinct cultivated landscape. Identifying and classifying the morphological characteristics of cultivated land are key to improving land utilization efficiency. This study focuses on the semiarid sandy areas of China. We obtained information on cropland morphology by judging high-precision remote sensing images and landscape pattern analysis, and then determined the spatial clustering characteristics of different plot morphologies through local spatial autocorrelation analysis. The results are as follows: cultivated land can be classified into five main types: simple large plots, complex large plots, simple small plots, complex small plots, and scattered plots, and there are significant differences in morphology between eastern and western plots. In addition, different morphology types of plots formed a variety of aggregation patterns; clustered plots are surrounded by scattered plots, showing a staggered distribution pattern. Farmers and land managers can make more informed decisions regarding irrigation, fertilization, and crop selection, and this knowledge can provide a basis for further optimizing the layout of cultivated land, identifying fragmented cultivated land, and scientifically recovering farmland to ensure more scientific and refined classification management and zoning protection of cultivated land.

Habitat quality assessment and multi-scenario prediction of the Gansu-Qinghai section of the Yellow River Basin based on the FLUS-InVEST model

Research on the impact of land use change on regional habitat quality, in various future scenarios, can effectively aid planning and decision-making for sustainable development at a regional level. The study conducted its research in the Gansu-Qinghai Yellow River section and used ArcGIS and a land use transfer matrix to analyze the spatiotemporal pattern of land use and land cover changes. The study assessed the changes in habitat quality in the Gansu-Qinghai Yellow River region between 1990 and 2020, using the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model, by evaluating the gains and losses. Simultaneously, 15 elements of the natural economy were chosen and examined for their temporal and spatial impact on habitat quality using the random forest model and spatially weighted regression model. To forecast land use changes in the Gansu-Qinghai Yellow River section for 2030, the Future Land Use Simulation Model (FLUS) model was utilized and a series of four scenarios (cultivated land protection scenario, ecological protection scenario, natural development scenario, and rapid development scenario) were employed. The research results indicate that over 70% of the Gansu-Qinghai Yellow River is occupied by grasslands, and only a small portion of the area, about 0.22%, is developed for construction purposes. The quality of the habitat in the Gansu-Qinghai Yellow River had a minor drop between 1990 and 2020, followed by an improvement. Habitat quality changes are primarily attributed to improvements, with variations across different areas, i.e., enhanced in the east and reduced in the central and western parts. The habitat quality of the Gansu-Qinghai Yellow River has improved in all four scenarios compared to 2020, as evidenced by the decrease in low-value habitats and increase in high-value areas. The ecological protection scenario has the highest average habitat quality value. These research results can be used to support policy development and ecological restoration initiatives in the Gansu-Qinghai Yellow River.

Dynamic simulation and analysis of land use competition patterns to support sustainable territorial spatial management: a case study of Shenyang City, Northeast China.

Under the context of territorial spatial planning in the new era, it is of great significance to analyze the future land use competition pattern to construct a sustainable and adaptive management strategy for territorial spatial development and utilization protection. Taking Shenyang, a megacity in Northeast China, as the case study area, and the geographic information system technologies and the patch-generation land use simulation (PLUS) model was used to simulate the land use competition pattern in 2030 under four scenarios. Meanwhile, the dynamic evolution of territorial spatial structure competition was monitored based on the perspective of agricultural, ecological, and construction land space. The results show that land use competition was driven by food security, economic growth, and ecological protection. The results showed that (1) the most frequent changes in cultivated land and construction land were found in 1980, 1990, 2000, 2010, and 2020, and their competitive advantage among land use types was obvious. As for the driving mechanism, the influencing effect of socioeconomic factors on land use type competition was more significant than that of natural factors. (2) The competitive dominance scenario of cultivated land protection and the synergistic dominance scenario of cultivated land, ecological, and construction could help optimize and control the land use competition pattern. (3) The information entropy and equilibrium index of the territorial spatial structure increase in both scenarios; the dominance index decreases, and the proportion of agricultural, ecological, and construction space is more coordinated. The results may assist a holistic understanding of land use change to coordinate the competition among agricultural, ecological, and construction space and facilitate the realization of high-quality territorial spatial development goals.

Assessment and simulation of ecosystem carbon storage in rapidly urbanizing areas based on land use cover: a case study of the southern Jiangsu urban agglomeration, China

Since China’s reform and opening-up period, the southern Jiangsu urban agglomeration has been one of the fastest urbanizing regions in the country. This rapid urbanization has led to dramatic changes in land use cover that have been the primary drivers of carbon stock changes in the terrestrial ecosystem. In this study, we utilize the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model and a patch-generating land use simulation (PLUS) model to analyze the land use changes and carbon stocks in the southern Jiangsu urban agglomeration over the past 30 years. We then simulate the carbon stock changes in the study area in the year 2050 under natural growth, cultivated land conservation, and ecological conservation scenarios. The results showed that 1) over the past 30 years, the urban area has increased by 2.98 times, reaching 7,408.42 km2 by 2020. In contrast, the area of cultivated and forested land has continued to decrease with rapid urbanization. 2) Between 1990 and 2020, the carbon stock of the urban agglomeration in southern Jiangsu decreased by 5.34%. The changes in the spatial distribution of carbon stocks are consistent with the changes in land use. 3) By 2050, the carbon stock loss was the largest under the natural growth scenario at 10.49 mt, while the carbon stock loss was the smallest under the cultivated land protection scenario at 0.97 mt. Under the ecological protection scenario, the carbon stock loss was 9.9 mt. The results indicate that the adoption of cultivated land and ecological protection measures can effectively control the reduction of carbon stock in rapidly urbanizing areas. 4) The conversion of cultivated land and forest land to urban land was the primary reason for the carbon stock reduction in the study area, which was primarily located in the urban outward expansion area. This study provides a reference- and data-based support for the management, decision-making, and planning in rapidly urbanizing areas.

Can We Prevent Irreversible Decline? A Comprehensive Analysis of Natural Conditions and Quality Factor Thresholds of Cultivated Land in China

Over the past two decades, China’s spatial distribution of cultivated land has been stable, yet there remains an urgent need to amplify grain productivity. The central scientific question addressed in this study is: How can we effectively evaluate the natural resource thresholds of cultivated land at a regional scale? Despite existing systems, there is a noticeable gap, particularly in this area of inquiry. Recognizing the present state of these resources and introducing more efficient management strategies is pivotal. This paper aims to research the restrictive situation of the natural resources background quality (NRB-quality) of China’s cultivated land by developing an innovative classification method and a short-board identification method and adopting cluster analysis and other technical methods. The results showed that (1) China mainly maintains medium-quality land (57.30%). The soil texture displayed a fine average grade of 1.39, while the biodiversity, soil pH, secondary land types, and cropping systems indicated poor conditions, with average scores of 2.01, 2.06, 2.26, and 2.33. (2) A notable difference in the restrictive factors of cultivated land quality emerged, with secondary land types of cultivated land (including paddy field, irrigated land, and dry land) being the only national short-board factor. Regionally, the cropping system, secondary land types of cultivated land, and natural region were identified as short-board factors in 31, 24, and 23 natural regions. (3) The regional difference in cultivated land quality leads to six different management strategies. Eastern regions emphasized stabilizing land distribution and infrastructure enhancement, while China’s western areas advocated cautious development and heightened ecological protection. The findings demonstrated regional differences in the status of cultivated land quality factors; implementing classified management approaches for cultivated land quality factors based on their characteristics is vital to preventing irreversible decline. The study serves as an important basis for the protection and utilization of cultivated land in the new era to clarify the NRB-quality differences of cultivated land in China.

How to Rebalance the Land-Use Structure after Large Infrastructure Construction? From the Perspective of Government Attention Evolution

Large infrastructure projects play a crucial role in regional development but can also negatively impact cultivated-land protection. This study focuses on the role of local governments in land-use conflicts and the rebalancing of land-use structures during large infrastructure construction. Using the construction of a reservoir in the Huaihe River as a case study, the research examines the evolution of government attention and the process of township local governments promoting land-use adjustment. The findings reveal that local governments go through a process of “Create–Reinforce–Adjust–Delivery” in their attention to reservoir construction to maximize their interests. Attention fluctuates in terms of reservoir construction, cultivated-land protection, and immigration-development assistance. Biased land-use decisions were made at different stages, leading to four stages of rebalancing efforts: “Generation–Challenge–Marked effect–Continuous negative impact”. This process provides insights into land-use decision-making and the rebalancing of land-use structure. The study suggests that the superior government should guide local governments to enhance attention to cultivated-land protection through laws and policies, while local governments should focus on the quality protection of cultivated land and mitigate the negative impact of rebalancing efforts.