The construction of ecological civilization and low-carbon transformation in the Yangtze River Economic Belt (YREB) are the key tasks of high-quality economic development in China. Based on the data of carbon emission intensity of 1 069 counties in the YREB from 2005 to 2019, the development trend and spatial characteristics of carbon emission intensity were investigated using statistical methods of nuclear density estimation, Dagum Gini coefficient, standard deviation ellipse and exploratory spatial data analysis. The results showed that: (1) The carbon emission intensity of the counties under the jurisdiction of the YREB generally showed a steady downward trend. The  dispersion degree and absolute difference had also decreased, and the absolute difference had narrowed. The carbon emission intensity of the YREB as a whole and the counties under the jurisdiction of the upper, middle and lower reaches demonstrated multipolar polarization, but tended to weaken. (2) The overall difference of carbon emission intensity in counties under the jurisdiction of the YREB showed a downward trend, and the degree of regional imbalance was generally at a high level. The main contribution source of the overall difference is the hypervariable density, with an average contribution rate of nearly 40%, followed by the intra-regional difference, with an average contribution rate of about 33%, and finally the inter-regional difference. (3) The regional distribution of carbon emission intensity at county levels showed a spatial pattern of northeast-southwest trend, and its distribution center of gravity showed a trend of first towards southwest and then turning back to northwest. The mode of local spatial agglomeration was mainly "low-low" agglomeration, with more districts and counties mainly distributed in eastern Sichuan and southwestern Chongqing in the upper reaches of the YREB, majority of Hunan and Jiangxi in the middle reaches and majority of Hubei. Based on this, efforts should be made to promote emission and carbon reduction according to local conditions and urban policies. This aims to enhance the spatial linkage and coordination between districts and counties, and to optimize the government assessment and supervision and accountability mechanism to jointly help the high-quality development of the YREB.

Under the concept of green and low-carbon development, it is of great significance to explore the spatial-temporal characteristics and the influencing factors of the efficiency of “cutting carbon, reducing pollution, expanding green” for urban land. Based on a panel dataset covering 108 cities from 2003 to 2021 in the Yangtze River Economic Belt, the undesirable output super-efficiency SBM model, kernel density estimation, spatial autocorrelation analysis, and spatial panel econometric models were used in this study. Findings found that: (1) The efficiency values showed an overall upward trend, with values rising from 0.338 in 2003 to 0.677 in 2021. These valuesshowed stage-specific characteristics in regional disparities and widening intercity differences, along with polarization phenomena. (2) Positive spatial autocorrelation was evident at the global level, whereas at the local scale, four types of agglomeration patterns were identified, i.e. high-high, low-low, low-high, and high-low. (3) A significant positive spatial spillover effect was confirmed, where a 1% increase in efficiency of “cutting carbon, reducing pollution, expanding green” induced a 0.155% rise in neighboring cities. (4) Spatial effect decomposition disclosed varying direct and indirect effects of influencing factors on the efficiency. Therefore, it was necessary to consider the spatial correlations and spillover effects among cities to enhance the efficiency of urban land changes in the Yangtze River Economic Belt.

The frequent occurrence of pollution disputes between inter provincial river basins reflects the long-standing game problem of "competition over cooperation" among local governments in river basin governance, and reflects the importance and urgency of strengthening collaborative governance to promote ecological environment protection in river basins. For this reason, China has implemented a major policy reform - Inter Provincial Watershed Ecological Compensation. Therefore, it is urgent to answer how the Inter Provincial Watershed Ecological Compensation achieves collaborative governance of watersheds and its policy effects. Inter Provincial Watershed Ecological Compensation was taken as a quasi experiment, and the logical approach to achieving coordinated watershed governance was explored. Based on balanced panel data from 30 provincial-level administrative regions in China from 2007 to 2020, the effect of inter provincial watershed ecological compensation were empirically examined using a multi period double difference method. The research results indicate that: (1) Inter Provincial Watershed Ecological Compensation can effectively balance the cost-benefit issues of different local governments in basin governance in the upstream, downstream, left and right banks, and are an effective strategic institutional arrangement for achieving coordinated basin governance. (2) The implementation of inter provincial watershed ecological compensation can significantly improve the resilience level of water ecology in the basin, and has become a new path for achieving mutual benefit and win-win in current basin collaborative governance. Based on research findings, corresponding policy recommendations are proposed from three aspects: constructing a comprehensive ecological compensation mechanism for the entire watershed in China, improving a market-oriented and diversified compensation system for the watershed, and improving the construction of a legal system for ecological compensation in the watershed.

Maintaining a high quality of water environment is an inevitable requirement for regional integration. The Yangtze River Delta (YRD), one of China's most populous and economically vibrant areas, has raised the bar for aquatic environment management in order to meet the demands of high-quality growth and regional integration. Green finance is an important tool to promote environmental governance. Based on the panel data of 41 cities in China's YRD region from 2011 to 2020, this paper applied the fixed-effects model and the spatial Durbin model to examine the water and environmental governance effects of green finance. It is found that: (1) the development of green finance had a significant positive effect on water environment governance in the region. The relationship between the two remained significant according to the endogeneity exploration and multiple robustness tests. (2) The governance effect of green finance on the water environment was characterized by significant heterogeneity. Cities with high levels of science and technology, economic development, and urbanization had more significant water environment and governance effects from green finance. (3) Green finance can promote water environment management through the mechanisms of industrial structure upgrading, green science and technology innovation, and government environmental governance.(4) Green finance was not always effective in the management of water pollution, and green finance did not show significant beneficial effects on the management of the water environment outside the region, and even the spatial spillover effect was negative and significant. Accordingly, policy recommendations were proposed in terms of encouraging the development of green finance, promoting cross-regional linkages between green finance and water pollution control, and encouraging technological innovation and the development of green industries.

Small wetlands are distributed widely. However, the soil carbon stock and ecological stoichiometric characteristics of the wetlands have received little attention, which may restrict the accurate calculation of the budget of wetland carbon stock. In this study, six types of wetlands in the Tangma Reservoir watershed in southern Jiangsu Province were selected, which included river, water-level-fluctuating zone of reservoir, open-water zone of reservoir, freshwater farm, agricultural pond, and paddy field. Specifically, soil profiles of 1 m depth were collected and analyzed for soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), and the ecological stoichiometric ratio. Soil SOC, C/N, C/P and N/P were measured as 3.65±3.60~8.17±6.26 mg/g, 7.7±4.6~10.8±2.5, 18.0±6.2~34.4±16.4 and 1.9±0.5~3.1±1.4, respectively. Significant differences of soil SOC, TN, TP, C/N, C/P, and N/P among different wetlands were identified (p < 0.01). These elements were generally higher in the water-level-fluctuating zone of reservoir and paddy field, and lower in the open-water zone of reservoir, river, and freshwater farm. The soil carbon density of the six types of wetlands ranged 4.41±3.94~9.37±5.81 kg/m2, which was lower than the average of national wetlands, but at a close level to the results of coastal wetlands and eastern lake wetlands in China. The relatively higher TN and TP indicated that the wetlands had a great potential for carbon sinks.

The evaluation of water resources utilization in the source area before and after the operation of the inter-basin water transfer project is of great significance for optimizing water resource allocation, promoting the coordinated development of water resources and economy, and improving the sustainable level of water resources. The water footprint of the water source area of the middle route of the South-to-North Water Diversion project from 2005 to 2019 was calculated in this paper. The evaluation index system incorporating regional water resources sustainability, ecological security, economic coordination and social coordination was constructed to evaluate and analyze the overall water consumption and water resource utilization status of the water source area. The results showed that: （1） By 2019, the overall total water footprint of the water source area had decreased to 7.316 billion m3, while the green water footprint had accounted for a relatively high proportion. The blue water footprint grew by 52.48% between 2005 and 2019. The grey water footprint showed a fluctuation during 2005-2013, but a significant decrease trend from 2014 to 2019; （2） The overall water resources ecological security level and the coordination level between water resources and society in the water source area were relatively good. The unsustainable state of resources was more severe. The coordination between water resources and economy was gradually weakened. This study provided comprehensive theoretical and data support for the formulation of decision-making plans and management methods for sustainable utilization of water resources in the source area of the middle route of the South-to-North Water Diversion Project. Analysis and assessment of water resources use and water footprint were conducive to obtaining efficient methods of water resources utilization, enhancing water resources protection, and providing reliable basis for effective allocation of water resources.

The study on the changing trends and driving factors of the Normalized Difference Vegetation Index (NDVI), an important indicator to reflect vegetation growth, is of great significance for maintaining regional ecological security. Taking Danjiangkou Reservoir area as the research object, this paper constructed a 1 km resolution NDVI series from 1982 to 2022, by using GIMMS NDVI and MODIS NDVI data based on pixel-level linear regression analysis. These data were used further to analyze the temporal and spatial characteristics of NDVI in the study area. The spatial heterogeneity of vegetation and the driving factors were explored using the geographical detector. The results showed that: (1) The annual mean NDVI increased at a rate of 0.002 6 per year. The spatial distribution of NDVI was characterized by higher values in the northwest and lower ones in the southeast. The areas of low-value were concentrated in low-altitude areas such as Hanzhong, Ankang and Shiyan. (2) NDVI within the reservoir area generally showed an improvement, but with a local degradation. The area with a significant improvement accounted for 98.23% of the total area, which was widely distributed in the whole research area. The degraded area accounted for less than 1%. (3) Annual potential evapotranspiration, elevation and geomorphology were the dominant factor influencing the spatial distribution of local vegetation. The interaction between sunshine hours and elevation had the greatest influence on the spatial distribution of NDVI. The interactions between the influencing factors showed either a two-factor enhancement or nonlinear enhancement.

Waves are one of the primary external forces causing soil erosion in the riparian zone of the Three Gorges Reservoir. Studying the characteristics of nearshore wave forces is crucial for understanding soil erosion processes in this area. However, the spatial and temporal variations of nearshore wave forces in the Three Gorges Reservoir remain unclear. This paper employed in-situ observation methods and relevant recommended formulas to quantitatively calculate and analyze the spatiotemporal variations of nearshore wave forces in the Three Gorges Reservoir, main and tributary streams. The results indicated that: (1) Nearshore wave forces in the Three Gorges Reservoir exhibited significant spatial and temporal heterogeneity (P<0.01), with values ranging from 0.02 to 12.14 kPa, showing a reservoir impounding cycle. The frequency distribution of nearshore wave forces could be fitted using the Lorentz distribution curve. (2) Nearshore wave forces increased with rising water levels. At a water level of 175 m, the average nearshore wave force was 1.7 times and 1.2 times that at 150 m and 165 m water levels, respectively. At 150 m water level, nearshore wave forces primarily ranged from 0 to 1.5 kPa, with a cumulative frequency of 91.4%. (3) There were significant differences (P<0.01) in nearshore wave forces between the main and tributary streams. The average nearshore wave force in the mainstream was three times that of the tributaries. (4) The variation in nearshore wave forces across different reservoir sections was irregular. However, at the same water level, the average nearshore wave forces in the Zigu, Badong mainstreams, which were closer to the Three Gorges Dam, were significantly higher than those in the Zhongxian mainstream, that was farther away from the dam. (5) The peak values of nearshore wave forces during typical days coincided with shipping activities, indicating that the intensity of shipping activities was a key factor causing significant differences in nearshore wave forces between the main and tributary streams. These research findings provided scientific references for studying the hydrodynamic characteristics of nearshore areas and the soil erosion environment in the riparian zone of the Three Gorges Reservoir.

Various waterbodies including ditches, ponds, and paddy fields are important components of  polders wetlands. Maintaining reasonable concentrations of key biogenic elements including carbon, nitrogen and phosphorus in polders is essential for the ecological function of wetlands. Taking the polders along the Le 'an River in Poyang Lake Basin as an example, this study explored the distribution pattern of concentrations of dissolved carbon (DOC), nitrogen (DTN), and phosphorus (DTP) in major waterbodies of polders, through field monitoring and sampling. A quantitative study was also conducted to reveal the effect of hydrological connectivity on element concentrations. All elements were distributed in the hierarchy of paddy field > pond > ditch, with mean concentrations of 9.5/13.8/19.0/34.2 mg/L (DOC)，0.6/1.1/0.82/8.8 mg/L (DTN)，0.016/0.025/0.036/0.12 mg/L(DTP), respectively. Concentration of biogenic elements was strongly correlated with hydrological connectivity, and the latter could explain up to 25.4% of the change of the concentrations. This finding implied that an improvement of connectivity could shorten the residence time of the elements and accelerate the turnover rates, and consequently resulted in decreased concentrations. The demand of flood control and water supply requires the necessary to control the concentrations of biogenic elements in polders. Therefore, in practice, it is suggested to manage the timing and duration of sluice gate opening/closing in order to restore an improved hydrological connectivity in polders.

The hydraulic microhabitat of spawning ground of Schizothorax Prenantihabitat is a multi-indicator set.What type of ecological spur dike angle is reasonable in the downstream water-reducing reach after the construction of Jiangshe dam? How to measure whether the water area after the restoration of ecological spur dikes still has the hydraulic characteristics of spawning ground? These issues involve the measurement and representation of more fuzzy concepts.Up to date, the engineers only rely on the accumulation of practical experience or model test to guide the ecological spur dikes angle of different rivers.In this paper, the similarity model of hydraulic microhabitat in habitat spawning ground was established by vague set after restoration, and the similarity standard for microhabitats in spawning grounds after restoration of the habitat of Schizothorax Prenantiwas constructed with reference to foreign spawning ground restoration cases.Based on the two-dimensional hydrodynamic model of average water depth, hydraulic microhabitat of habitat spawning ground of Schizothorax Prenanti in the repaired river section of Jiangshe dam were simulated in terms of water depth, flow velocity, vorticity,and other factors.The effects of different angles and types of ecological spur dikes were studied on the hydraulic microhabitats of habitat spawning ground of Schizothorax Prenanti.Then, the improved vague set was used to verify the repair effect of ecological spur dikes.The research results indicated that the orthogonal L-shaped ecological spur dikes had the best repaired effect when there was a small flow and a certain distance between ecological spur dikes.The results also demonstrated that a larger ratio of the effective length of ecological spur dikes to the effective width of the river facilitated a higher similarity of hydraulic microhabitats after restoration.

Based on the land use data of the Yangtze River Delta (YRD) urban agglomeration in 2000, 2010, and 2020, this article analyzed the growth and decline of the " Production-Living-Ecological" (PLE) space in the past 20 years.Using 2020 as the benchmark, a patch generated land use change simulation (PLUS) model was used to simulate and analyze the different evolutionary characteristics and ecological environmental effects of the "PLE" space in the region in 2030 under three scenarios: natural development, economic priority, and ecological protection.The results showed that: (1) From 2000 to 2020, the production space of the YRD urban agglomeration would continue to shrink.The living space would continue to expand, and the ecological space would first increase and then decrease.(2) From 2000 to 2020, the ecological environment quality index would continue to decrease from 0.4837 to 0.4765, and the low-quality areas would continue to expand.The continuous reduction of agricultural production land and the occupation of forest and water ecological land were the main factors leading to the decline in ecological environment quality.(3) The living space would expand and the production space would shrink in all the three scenarios.The production land would decrease the least in the ecological protection scenario.(4) Under the ecological protection scenario, the ecological environment quality index of the study area was the highest, and the ecological environment quality level showed a trend of continuous improvement.It was suggested that strengthening the protection of cultivated land and forest land, rational planning and layout, and improving urban green space would promote the sustainable development of social economy under the ecological protection scenario.

In the context of rapid urbanisation, building an urban-rural ecological security pattern is an important way for China to narrow the gap between urban and rural ecological security levels and to promote integrated urban-rural ecological development.The urban-rural ecological differences lead to the slow process of urban-rural ecological integration development.Taking Wuhan city as an example and urban-rural ecological integration as an orientation, this paper analyzed the current level of urban-rural ecological integration and its influencing factors.A comprehensive ecological resistance surface based on the measurement of the comprehensive impact degree of ecological integration was constructed.The ecological sources at meso-scale and theimportant ecological corridors based on the least cumulative resistance and gravity model were identified.The corridors were optimized by using a hydrological analysis model, and an overall urban-rural ecological safety pattern in Wuhan was constructed.This study showed that: (1) There was obvious spatial differentiation in the level of urban-rural ecological integration in Wuhan, and urban-rural ecology was in an unbalanced state of development; (2) The main driving force for the development of urban-rural ecological integration was the ecological environment and anthropogenic activity factors, with less socio-economic impacts; (3) A ‘three horizontal and two vertical’ network of ecological security patterns were constructed, which included 51 urban and rural ecological sources, 115 important ecological corridors, 220 radial corridors and 129 ecological nodes; (4) The ecological resistance surface corrected by the urban-rural ecological integration influence index was more in line with the urban-rural reality, and the ecological security pattern demonstrated the effect of promoting the development of urban-rural ecological integration.The ecological security pattern of urban and rural areas in Wuhan was constructed to provide a more microscopic theoretical reference for the optimization of ecological space in urban and rural areas, as well as to provide a scientific reference for the promotion of ecological integration between urban and rural areas, for the safeguarding of ecological security in urban and rural areas, and for the promotion of sustainable development in the region.

Yangcheng Lake is the third largest freshwater lake on the Taihu Plain.Based on the monthly monitoring data of water quality of Yangcheng Lake from 2019 to 2023 and the field survey data of water environment in flood seasons in 2023, this paper analyzed the temporal and spatial variation of water quality in flood seasons.The causes of pollution was also analyzed from the perspectives of exogenous input, endogenous release and pollution reduction of aquatic vegetation.The results showed that the water quality of the Lake in the flood seasons from 2019 to 2023 was mainly characterized by Class IV.The change of water quality index concentration in a year demonstrated a certain periodicity, and the water pollution degree in the flood season was increased year-on-year.Total phosphorus was the main over-standard factor of water quality.The total phosphorus in the lake was mainly composed of dissolved inorganic phosphorus.From the perspective of spatial distribution, the water quality of East Lake was better than that of West Lake and Middle Lake.The water quality of non-restoration aquaculture area and aquatic vegetation restoration area was better than that of enclosure aquaculture area.The pollutant concentration at the estuary point had a significant impact on the water quality of Yangcheng Lake.The contents of permanganate index, total phosphorus, total nitrogen and other indicators at the estuary point were significantly higher than those in the lake area, which was the key factor affecting the water quality of the Lake.The results showed that the phosphorus content in sediments of the purse seine culture area was higher.During flood seasons, the increase in temperature resulted a decrease in the dissolved oxygen of water, and consequently a high risk of release of the total phosphorus from the sediments.In addition, aquatic vegetation planting may have a strong correlation with transparency improvement, permanganate index reduction and chlorophyll a reduction.The reduction of phosphorus by aquatic vegetation may be mainly related to the content of total dissolved phosphorus.

Hubei Province is located in the middle reaches of the Yangtze River, which possesses many lakes.In recent years, some lakes faced increasingly ecological environment problems, such as water quality decline and aquatic ecosystem degradation.In this study, the four largest lakes (Honghu, Liangzi Lake, Futou Lake, and Changhu) were selected for investigation.The results showed that the water quality of all four lakes showed different degrees of deterioration from 2016 to 2023.Among them, the water quality of Honghu Lake experienced the most significant deterioration, and the classification of surface water environmental quality standard dropped from Class III in 2016 to Class V.The total phosphorus and permanganate index were the main parameters that exceeded the standards.The survey conducted in the spring and summer in 2023 showed that Honghu Lake was in a moderate eutrophication state.Changhu Lake was in a mild eutrophication state, and Liangzi Lake and Futou Lake were in a moderate to mild eutrophication state.The biodiversity of phytoplankton, zooplankton, and benthic animals in the four lakes was at a relatively low level.This assessment showed that the water ecological environment quality of Honghu Lake was poor, Liangzi Lake and Futou Lake were in average level, and Changhu Lake was poor in spring and in average in summer.

Kunming city is the focal point of economic and social advancement in Yunnan Province.The city faced a pronounced contradiction of the rapid pace of socioeconomic progress and the imperative of ecological preservation of land resources.This study utilized the Pressure-State-Response (PSR) model to assess land ecological security from 2000 to 2020.Key factors impeding land ecological security were identified using the obstacle degree model.Using the PLUS model, scenarios reflecting natural development, ecological protection, and cultivated land preservation were simulated for 2040.The results revealed that: (1) Land ecological security warnings for 2000-2020 exhibited a spatial distribution trend of high in the central regions and low in the periphery.Higher values were presented in the north compared to the southwest.Evident challenges in balancing development and protection around Dianchi Lake were found.(2) Inefficient land utilization, exacerbated by social and economic pressures, was the primary threat to land ecological security.(3) Attaining synergy between socio-economic and ecological benefits proved elusive within singular scenarios, which necessitated a comprehensive approach across multiple scenarios to regulate land changes effectively.Exploring efficient land utilization methods within the constraints of limited resource-carrying capacity was crucial for Kunming city to reconcile the contradiction between conservation and development, which necessitated a shift in the development paradigm and enhancement of land use efficiency, alongside intensified land use management.

In the context of global climate warming, the contribution of agricultural carbon emissions cannot be ignored.Improving the carbon emission efficiency of cultivated land use from the perspective of farmers is the key entry points to achieve the reduction in cultivated land use carbon emission.Based on the micro survey data of farmers in Changde City of Hunan Province, the evaluation index system of farmers' livelihood capital was constructed with reference to the sustainable livelihood analysis framework.The impact of farmers' livelihood capital on carbon emission efficiency of cultivated land use was analyzed by using the stochastic frontier production function model.The results showed that: (1) The overall livelihood capital level of farmers in the study area was not high with obvious differences.The average livelihood capital was only 0.102, which was superior in material capital, human capital and social capital, while there was a need for the natural capital and financial capital to be strengthened; The degree of non-agricultural farmers was high, whose livelihood strategies were mainly part-time and non-agricultural.The structure of livelihood capital of farmers with different livelihood strategies was different.The order of livelihood capital level was: part-time farmers (0.111)> agricultural leading farmers (0.107)> non-agricultural leading farmers (0.093).(2) Livelihood capital had an impact on the cultivated land use carbon emission efficiency.Different livelihood capital structure of different livelihood strategies types had different impacts on the cultivated land use carbon emission efficiency: For agricultural leading farmers, the cultivated land use carbon emission efficiency was mainly positively affected by five livelihood capital; For part-time farmers, it was mainly positively affected by material capital and financial capital; For non-agricultural leading farmers, it was mainly positively affected by material capital and social capital and was negatively affected by human capital.(3)The impact of specific indicators of livelihood capital of different livelihood strategies types was also different.In conclusion, the targeted policies for different types of farmers based on their livelihood capital should be encouraged to improve the carbon emission efficiency of cultivated land use, which included the enhancement of the livelihood capital of agricultural dominant farmers, the encouragement of the livelihood diversification of part-time farmers, and the promotion of the return of non-farmer labor.

Uncovering the effects of different land consolidation modes on farmers’  livelihood stability can provide new perspectives for scientifically evaluating the practical performance of land consolidation, and also provide new methods for effectively improving the sustainability of farmers’  livelihoods.Based on the analysis of the influencing mechanism of different land consolidation modes on farmers’  livelihood stability, a difference-in-differences model was constructed using 949 questionnaires from farmers in Hubei Province to reveal the net effect of different land consolidation modes on farmers’  livelihood stability.The results indicated that the local government-dominant mode significantly decreased the composite index of farmers’  livelihood stability by 0.032.Specifically, the indices of natural resource dependence, livelihood richness, and livelihood balance obviously decreased by 0.016, 0.012, and 0.034, respectively; the index of income dependence significantly increased by 0.034.In contrast, the new agricultural business entities-dominant mode evidently increased the composite index of farmers’  livelihoods stability by 0.045.Specifically, the indices of natural dependence and income dependence obviously reduced by 0.055 and 0.039, respectively; the indices of livelihood richness and livelihood balance significantly increased by 0.020 and 0.039, respectively.Compared to the local government-dominant mode, the new agricultural business entities-dominant mode significantly decreased the index of natural resources by 0.055.Therefore, it is highly recommended to strengthen the farmer-oriented principle of local government-dominant mode, and increase the proportion of new agricultural business entities-dominant mode to improve farmers’  livelihoods stability.

Understanding the spatial distribution characteristics and its influencing factors of cropland topsoil available potassium contents is essential for field nutrient management and soil resource conservation.Based on 4409 surface (0~20 cm) soil sample points collected during 2017-2019, the spatial distribution pattern and the influencing factors were analyzed in this study, using geostatistical methods, correlation analysis, analysis of variance and random forest model.The results showed that the available potassium contents in the study area ranged from 10.00 to 373.00 mg/kg, with a mean value of 110.48 mg/kg, which was lower than that of the national average (139 mg/kg); The coefficient of variation was 50.12%, which indicated a moderate spatial variability.The results of the semi-analysis of variance (ANOVA) showed that the best theoretical model was the exponential model.The model indicated a coefficient of determination of 0.975, the nugget effect of 62.9%, and the variability range of 23.5 km, which implied that the spatial distribution was determined by both structural factors and stochastic factors.The interpolation results showed that the cropland topsoil available potassium contents in the Sichuan Basin demonstrated a patchy spatial distribution pattern.Random forest model analysis showed that soil texture and pH were the most important factors affecting the cropland topsoil available potassium contents in the study area, followed by temperature and rainfall, while the effects of straw return, potash fertilizer application, topographic factors and soil type were relatively weak.The above results indicated that soil properties were the primary controlling factors for the spatial distribution of cropland topsoil available potassium contents.Under cultivation conditions, regulating soil texture and soil pH was the key to increase the cropland topsoil available potassium content.The formation of measurements such as straw return and fertilizer application should fully consider the effects of climate, topography and soil type.