Sustainable Use Of Land Resources Research Articles

Impact of digital economy on urban land green use efficiency: evidence from Chinese cities

Abstract Improving urban land green use efficiency (ULGUE) is essential for achieving the sustainable use of land resources and the high-quality economic development of cities. The digital economy has overcome spatial and locational constraints, blurred the boundaries between industries, and created a collaborative and open economic model, inevitably affecting urban land utilization. However, whether the digital economy will affect ULGUE and how such an effect would take place are still unclear. This study evaluates the digital economy and ULGUE of Chinese cities from 2011 to 2019 and systematically analyzes both the direct and indirect impact mechanisms through which the digital economy affects ULGUE. The results show that the digital economy can significantly enhance ULGUE, and these results prove to be reliable, as shown by various endogeneity treatments and robustness tests. The digital economy enhances ULGUE by optimizing the industrial structure (structural effect), increasing green technology innovation (technical effect), and agglomerating digital talent (scale effect). Moreover, land finance dependency plays an adverse moderating role in the relationship between the digital economy and ULGUE. Further heterogeneity analysis shows that the promoting effect of the digital economy on ULGUE takes full effect in the eastern cities, larger cities, and cities with high levels of digital economy development and land marketization. This paper presents recommendations for supporting the balanced and integrated development of the digital economy across regions and provides differentiated development strategies to enhance ULGUE in the context of digitization.

Searching for the Profitability of Energy Crops: An Agroecological–Economic Land Use Suitability (AE-landUSE) Model

The current geopolitical and energy market instability calls for speeding up the EU clean energy transition to increase energy security in all the European regions and make Europe the first climate-neutral continent by 2050. Among renewable energies, modern bioenergy is a promising near-zero-emission fuel for increasing energy security in the heating, electricity and transport sectors while promoting growth and job creation, especially in rural areas. In such a context, energy crops will continue to play a key role. Since agricultural planning is a complex issue, especially when energy crops could compete with food ones, we propose an agroecological–economic land use suitability model (AE-landUSE model) to promote the sustainable use of land resources. The AE-landUSE model was developed by integrating cost–benefit analysis (CBA) and land use suitability analysis (LSA) within geographic information systems (GISs). Tested in the Basilicata region (Southern Italy), comparing two different energy crops (rapeseed and cardoon), the results show the model’s utility in identifying suitable areas for energy crops where the investments will be cost-effective. The proposed model will help decision-makers in energy-agricultural planning to increase energy security sustainably.

The Impact of Digital Finance on the Green Utilization Efficiency of Urban Land: Evidence from 281 Cities in China

In the era of digital economy, digital finance, as an innovative financial model, plays an important role in driving urban industrial transformation and development, technological innovation, industrial upgrading and sustainable utilization of energy, and has a significant impact on sustainable urban development. At present, in the process of building a new pattern of Chinese-style modernization in China, it is of great significance to improve the green use efficiency of urban land through digital finance and realize the sustainable use of land resources and the sustainable development of the city. The current study employed 281 Chinese cities from 2010 to 2020 as research samples to investigate the effects of technological financing on the productivity of city land green usage. Based on the ideas of responsible growth and efficient urban development, an assessment index system was developed. Comprehensive empirical tests, such as the Super-SBM model, fixed effect model, and mediation effect model, were implemented in the research. The study’s findings indicate that: (1) Throughout the research period, the benchmark model’s regression outcomes demonstrate that digital banking impacts urban land’s green development efficiency, with positive moderating effects offered by environmental legislation; the optimization of industrial structure has not yet played a positive regulating effect. (2) Urban area green usage performance is more clearly impacted by the extent of use and the degree of digitization, according to the regression results of digital financing heterogeneity. The positive effect of online financial services on a city’s green use efficiency occurs mainly in eastern cities and southern cities, given the results of urban development level difference. In light of resource endowment unpredictability, “non-resource cities” stand to gain more from global finance’s encouragement of resource-efficient urban land use than do “resource cities”. The results of the mechanism test indicate that there is a strong mediating influence from digital finance, city land environmental use productivity, and green technological breakthroughs. In consideration of these results, the following measures are suggested in this paper: (1) Persist in advocating for the transformation of traditional finance into online financing. (2) Intensify the impact of significant variables on the environmentally friendly use of urban areas. (3) Encourage technology creativity and execution through the application of technological economics.

Virtual land trade and associated risks to food security in China

International trade can help alleviate the scarcity of arable land by importing agricultural and food products. In the context of climate change and socioeconomic development, the patterns in economic and resource flow embodied in the global food trade may be subject to further changes that present risks for economies with scarce land resources, such as China. These conditions exacerbate ongoing food security challenges, yet have so far not been well understood. Here, we combined the environmentally extended multiregional input-output (EE-MRIO) model, Geopolitical Supply Risk (GeoPolRisk) method, and scenario analysis to provide a comprehensive overview of global, virtual land trade patterns caused by China's food consumption and associated virtual land supply risk faced by China. Our results show that, from 1995 to 2015, China has experienced increasing GeoPolRisk of virtual land supply related to food consumption, roughly fivefold, mainly due to growth in total virtual land consumption and changes in trade structure. From 1995 to 2015, total food consumption-related virtual land in China has increased by approximately 35.1%, and the share of foreign land has increased from 6.3% to 43.3%, with the largest land sources shifting from low-income regions (such as Asia and Africa) to more industrialized regions (such as the United States and Australia). Meanwhile, socioeconomic development and dietary changes are the main antecedents to total virtual land consumption, potentially affecting GeoPolRisk. Our results suggest the need for urgent adjustments for a balanced distribution of virtual land sources and to promote healthy dietary transitions and improve agricultural productivity in the future. Our study offers significant information that can guide potential solutions to the sustainable use of land resources and reduce the GeoPolRisk of virtual land trade for decision-makers, thereby facilitating food security.

Land degradation neutrality in the Penza region

This study is carried out in order to calculate the neutral balance of the territory of the Penza region using the trend.earth program. In the course of the study, data on current land use, climatic conditions and changes in land cover are collected and analyzed. Using the trend.earth program, modeling of various scenarios of impact on land coverage is carried out in order to determine possible strategies for improving land management in order to achieve a neutral balance. The results of this study can be used to develop practical strategies for the sustainable use of land resources and to reduce the negative impact on the environment in the Penza region. The study of the neutral balance of the territory of the Penza region should take into account the existing rates of change in land cover, including the expansion of agricultural land, loss of forests and changes in water resources. When using the trend.earth program to model possible scenarios, potential impacts on biodiversity, climatic conditions and ecosystem sustainability should also be taken into account. The results of this study will identify potential locations for forest restoration, optimization of agricultural land use and other strategies to achieve a neutral balance in land management. The study will also provide important information for the development of practical recommendations for the sustainable development of the region. In addition, the assessment of the neutral balance of land use using trend.earth will allow assessing potential scenarios of changes in land cover in the context of climate change and economic development. This will allow factors such as carbon stocks, biodiversity conservation and ecosystem sustainability to be taken into account when developing land management strategies.

Coupling analysis of land use change with landscape ecological risk in China: A multi-scenario simulation perspective

The continuous change of global land use and intense human activities lead to the constant change of landscape ecological risk (LER). The increase of LER will pose a serious threat to human welfare and sustainable development. In previous studies, there were few studies on coupling coordination between land use intensity (LUI) and LER in multi-scenario simulation. Therefore, it is of a certain significance to study the coupling and coordination relationship between LUI and LER in a long-term multi-scenario simulation in the future for the sustainable use of land resources and the management of ecological risk. Based on the multi-scenario land use simulation data of China in 2010, 2050, and 2100, this study selects the comprehensive index of land use intensity, landscape pattern index, spatial autocorrelation, and coupling coordination methods to analyze the spatio-temporal characteristics of LUI and LER from 2010 to 2100, as well as the coupling coordination relationship between them. The results show that the overall LUI of China remains stable at around 200 from 2010 to 2100, with a spatial distribution that is “low in the northwest and high in the southeast.” The LUI of China decreases under the balanced resources scenario and global environmental protection scenario, while the regional economic development scenario and regional environmental protection scenario exhibit an increasing trend. The overall LER in China is approximately 0.150, with a spatial distribution that is “high in the north and low in the south.” The four scenarios exhibit a downward trend from 2010 to 2100. There is significant spatial dependence between LUI and LER in China, with the largest number of counties exhibiting reluctant coordination between the two (accounting for nearly 45%), while their interaction and mutual influence remain strong. Thus, this study may contribute to understanding this relationship and to creating effective landscape ecological risk management policies.

An integrated accounting system of the economic-social-ecological framework for assessing the value of intensive land use: A case study of the Taihu Lake governance project

Assessing the value of land resources is a prerequisite for resource management, as well as for resolving the conflict between supply and demand. In the realm of intensive land use (ILU), a standardized framework for accounting methods from a project perspective has yet to be established. Therefore, taking the Taihu Lake governance project (TLGP) (which includes the Xingou River project, Xinmeng River project and Zoumatang River project) as a case study, this paper firstly constructs an integrated value accounting system based on economic, social and ecological frameworks. Furthermore, with consideration of physical parameters, we incorporated the integrated land section price method, income reduction method, alternative market method, and equivalent factor method are all incorporated to assess the value of ILU at distinct stages within the research area. This approach serves to elucidate the evolving dynamics of ILU valuation. The results showed that: (1) There were significant differences in the values generated by the ILU in different projects. The integrated value of the TLGP brought about by ILU was 177,189,300 yuan, and the ILU of the Xinmeng River project was significantly higher than the Zoumatang River project and the Xingou River project. (2) The ILU at different stages basically displayed the law of diminishing marginal utility. Consistent with changes in the different stages of the TLGP, the value of ILU in Stage I of the Zoumatang River project and the Xingou River project was significantly higher than that in Stage II. Additionally, the accounting system proposed in this study has the advantages of reasonable index setting and simple process operability. This helps to realize the comparison of ILU values across projects and stages. The results of this study can provide a reference for the management and sustainable use of land resources during the construction of water conservancy and other projects.

Analysing Factors Influencing Land Use Planning for Sustainable Land Resource Management in Vietnam: A Case Study of Dan Phuong District in Hanoi City

Land use planning is an important task for every country in the world to ensure the sustainable use of land resources for economic and social development activities. However, many land use plans have not achieved their desired effectiveness due to a lack of consideration and evaluation of factors affecting the land use planning implementation process. This study was conducted to answer the following question: what are the main factors influencing the land use planning process in Vietnam? In this study, we use multivariate regression to identify the main factors influencing land use planning in Vietnam, including the economic factor group; institutional and policy factor group; urbanisation factor group; planning factor group; social factor group; environmental factor group; and organisational and implementation factor group. The results identified five groups of factors influencing land use planning in the Dan Phuong district through the influencing factor analysis method, including policy (Po), economy (Ec), society (So), environment (En), and others (Ot). In addition, the linear regression model obtained for land use planning in Dan Phuong district is as follows: land use planning = 0.408Po + 0.454Ec + 0.398So + 0.368En + 0.259Ot. In which the group of factors with the strongest influence was the Eco factors (β = 0.454), the second was the Po factors (β = 0.408), the third was the So factors (β = 0.398), the fourth was the En factors (β = 0.368), and lastly, there were the Ot factors (β = 0.259). The results of the analysis were used to plan land use effectively and according to local conditions. This can help managers to find solutions for the sustainable use of land resources in the future.

Identifying the trade-offs and synergies of land use functions and their influencing factors of Lanzhou-Xining urban agglomeration in the upper reaches of Yellow River Basin, China

Identifying the interactions of land use functions (LUFs) is of great significance for alleviating the contradiction between human and land, and promoting sustainable use of land resources. However, few studies concerned the interactions of LUFs in urban agglomerations of ecologically fragile areas in China at a fine scale. In this study, we constructed a quantitative and visualized evaluation system of LUFs that conforms to three primary functions, ten sub-functions, and nineteen indicators of Lanzhou-Xining urban agglomeration (LXUA) in the upper reaches of the Yellow River basin based on the production-living- ecological functions. Then, the comprehensive evaluation method, hot spot analysis, and geographic weighted regression (GWR) model were used to identify the interactions among LUFs and influencing factors of LXUA from 2000 to 2020 at the county and grid scales. The results show that the LXUA is dominated by ecological function (EF), and EF and living function (LF) showing a “U” shaped change feature, while production function (PF) show an inverted “U” shaped change feature. Meanwhile, the cold spots and hot spots of PF and EF present the spatial characteristic of “overall dispersion and local aggregation”, while the LF has no cold spots, and the hot spots present the spatial characteristic of “point-axis”. Moreover, the PF and LF are in a synergistic relationship at two scales, with complementarity in space, while the EF and PF and the PF and LF are both in a trade-offs relationship, with overlap in space. Finally, socioeconomic development factors have remarkable impact on LUFs at the county scale, while LUFs at the grid scale is the comprehensive result of natural conditions, socioeconomic factors, accessibility and political factors. The results can provide references for the LXUA to differentiated design the land use policy, and provide empirical case for other ecologically fragile areas to alleviate the trade-offs of LUFs.

Refined Evaluation of Soil Quality Sustainability in the Main Grain-Producing Areas of Heilongjiang Province

An evaluation of soil quality sustainability can support decision making for the sustainable use of land resources. However, certain current problems associated with these evaluations remain unaddressed, e.g., the evaluation indicators do not fully reflect soil quality risks and the evaluation scale is not sufficiently small. In this study, 25,000 spatial grids of dimensions 3 km × 3 km are used to divide the major grain-producing regions in China, namely, the Sanjiang Plain and the Songnen Plain of Heilongjiang. Then, the soil erosion modulus, nutrient balance index, soil organic carbon (SOC) storage, heavy metal soil pollution index and crop productivity are calculated for each grid using the RULSE model, nutrient balance index model, soil type method, geoaccumulation index method and mechanism method, respectively. A spatial grid cluster analysis method is used to thoroughly evaluate and analyze the sustainability of soil quality in each grid. The results show that the overall soil status of the study area is good. The soil and water conservation levels are high, the soils show low levels of contamination, the crop production potential is high and the ratio of highly sustainable to moderately sustainable soils is approximately 2:1. Only 2.74% of the land is rated extremely unsustainable and needs to be restored to a basic level of productivity before subsequent functional restoration can be carried out. This study provides a new method for the fine-scale evaluation of soil quality and contributes to the management of land resources.

On Environmental Protection and Sustainable Utilization of Land Resources

In today’s era, with the rapid development of social economy and the rapid increase of urban population, the demand for land resources is becoming increasingly strong. However, as is well known, the land resources on Earth are limited. If we want to achieve long-term development, we must take the path of sustainable development and use land resources sustainably. At the same time, the sustainable use of land resources and environmental protection are also inseparable, and the two are complementary. At present, China should rely on the superiority of the socialist system, mobilize various forces, coordinate planning, highlight key points, and implement step by step, while following natural and economic laws, to achieve the goals of environmental improvement and sustainable land resource utilization as soon as possible.

Spatiotemporal Characteristics and Habitat Quality Analysis in the Temperate Desert Sub-Region of Ordos Plateau, China

Habitat quality has great significance in terms of regional ecological conservation and human welfare. In this study, we evaluated the spatial and temporal characteristics of land use and habitat quality in the temperate desert sub-region of the Ordos Plateau using patch-generating land use simulation (PLUS) and integrated valuation of ecosystem services and trade-offs (InVEST) models. From 2000 to 2020, the areas of grassland, cropland, and unused land in the study area increased significantly; the areas of water bodies and woodland increased slightly; and the area of wasteland decreased significantly. Moreover, the habitat quality in the temperate desert subzone of the Ordos Plateau showed a trend of initial increase and then decrease between 2000 and 2020. The areas of lower and low habitat quality first decreased and then increased, and the overall area decreased over time. Conversely, the areas of high and higher habitat quality initially increased and then decreased, and the overall area increased over time. The area of medium habitat quality first decreased and then increased, although the overall change was minimal. Based on the PLUS model, the predicted habitat quality of the study area in 2025 under the natural development scenario was compared to that predicted under the ecological conservation scenario. The comparison of results showed higher habitat quality and lower habitat degradation under the ecological conservation development scenario. These results can be used to provide a scientific basis and decision reference for the sustainable use of land resources and encouragement of high-quality socio-economic development in the temperate desert sub-region of the Ordos Plateau.

Assessment of Land Ecological Security Based on the Boston Model: A Case Study from China

Land resources are essential natural resources and strategic economic resources for human survival and development. However, human improper use has brought unprecedented pressure and challenges to the ecosystem. Therefore, the assessment and analysis of land ecological security status and the identification and diagnosis of obstacles affecting land ecological security are helpful to avoid land ecological security problems caused by improper land use at the source and provide a theoretical basis for the sustainable use of land resources and the construction of ecological civilization in China. Based on the data from 2006 to 2020, this study constructed the land ecological risk-evaluation index system and land ecological health-evaluation index system. AHP, entropy method, combination weighting method, TOPSIS model, Boston matrix and obstacle degree model were used to assess the land ecological security situation in Nanyang City and to analyze the obstacle factors. The results show the following: (1) during the study period, the land ecological risk value of Nanyang City exhibited a Kuznets inverted “U” curve change, while the land ecological health value showed a “U” curve change; (2) the overall level of land ecological security in Nanyang City has gradually improved, with a security level pattern of “relatively safe (2006–2020)–unsafe (2011–2016)–relatively safe (2017–2019)–safe (2020)”; (3) the main obstacle factors of land ecosystem were the following: erosion area, sewage discharge, area of waterlogging control, grain sown area, coverage of urban green built-up area and farmland effective irrigated area.

Environmental and legal priorities in the implementation of land rights in Ukraine

The paper raises the issues of ensuring environmental safety in the process of land use. Particular attention is paid to the necessity of implementing the constitutional principles of recognizing land as the main national wealth under special protection of the State, the binding nature of ownership and ensuring environmental safety. The binding nature of land ownership, which is primarily due to the natural origin of land, is revealed. The understanding of land as a territorial basis for the natural and anthropogenic environment determines a special procedure for its use, which is subordinated, first of all, to the protective content of such legal relations, due to its exceptional value as the main national wealth. Therefore, the environmental component becomes crucial for ensuring sustainable use of land resources. The author raises the issue of concluding protection agreements in the area of agricultural land use. It is proposed to preserve and expand protected areas as the basis for sustainable land use. Particular attention is paid to the negative impact of military operations on the state of land resources, the need to identify and record cases of negative environmental impact, and to take into account the experience of implementing a new environmental policy by the states which restored their economies in the post-war period. According to the results of the study, the peculiarities of exercising property rights in the use of land as a condition of life for the landowner and society as a whole, including preservation and increase of the area of land as natural objects that have undergone the least anthropogenic interference are outlined; introduction of protective contractual relations in the use of commercial agricultural land in order to ensure its quality condition, through certain mechanisms of compliance with crop rotation, land zoning, land protection is also covered; conducting an assessment of the adverse impacts on the land fund resulting from the armed aggression of the Russian Federation, and implementing measures to compensate for the damages and restore the condition of the affected lands.

Evaluation of Soil Quality in Five Ages of Chinese Fir Plantations in Subtropical China Based on a Structural Equation Model

Soil quality evaluation provides necessary and fundamental data and information for understanding the current situation of the soils and for promoting the sustainable use of land resources. In this study, soil quality was assessed by developing a structural equation model (SEM) in five aged Chinese fir plantations, located in the same soil type, with similar site conditions, in Subtropical China. A total of 150 soil samples were taken from the five aged stands of Chinese fir forests: 8-year-old young forests (stand I), 14-year-old middle-aged forests (stand II), 20-year-old near-mature forests (stand III), 26-year-old mature forests (stand VI), and 33-year-old over-mature forests (stand V). Fifteen soil indicators, including soil bulk density (BD), capillary porosity (CP), total capillary porosity (TCP), water holding capacity (WHC), soil organic matter (SOM), total nitrogen (TN), available nitrogen (AN), available phosphorus (AP), available potassium (AK), soil pH, soil acid phosphatase (ACP), invertase (INV), urease (URE), and catalase (CAT), were measured. The SEM was used to determine the weight of each soil indicator, and the soil quality index (SQI) was estimated for the Chinese fir plantations. Results showed that soil physical indicators, such as BD, CP, TCP, WHC, and chemical indicators, including SOM, TN, and AN, significantly degraded in stand II groups compared with the stand I groups, but were significantly recovered in the stand III groups. However, the enzyme activity of soil biological indicators had different patterns with changes in soil physical and chemical properties. The calculated SQI in the studied Chinese fir forests ranged from 0.4084 to 0.7298, which was significantly higher in the stand V and lower in the stand II (middle-aged stand) than in the other four aged stands (p < 0.05). The SEM weight analysis showed that the BD, SOM, and ACP were the most important indicators affecting the physical, chemical, and biological properties of the soils in Chinese fir forests in the study area. This study provided an innovative scientific approach for estimating the weight of SQI in forests and a theoretical basis and practical application for sustainable management of Chinese fir forest ecosystems.

Evaluation of the Sustainable Use of Land Resources in the Cities along the Jiangsu Section of the Beijing–Hangzhou Grand Canal

Sustainable development is an important topic of urban research. The rational use of land resources is of great significance for urban development and is conducive to promoting regional governance and coordinated development. The purpose of this study was to construct an effective evaluation framework for urban land resources to maintain sustainable urban development. Taking the cities along the Jiangsu Section of the Beijing–Hangzhou Grand Canal as the research object, this study constructed an evaluation system for the sustainable use of land resources including the dimensions of economic level, social development, and environmental resources. The statistical data for 2010, 2015, and 2020 were selected to comprehensively calculate and evaluate the level of sustainable use of land resources in the study area via the analytic hierarchy process (AHP)-entropy combined weight method, which combines the analytic hierarchy process and the entropy weight method. According to the research results, the sustainable use of land resources in the study area presented an overall upward trend from 2010 to 2015, and an overall downward trend from 2015 to 2020. Overall, the study area was in a critically sustainable stage, although the annual change rate of the level of sustainable use of land resources showed significant fluctuations and exhibited a spatial pattern of progressive increase from north to south. The cities in southern Jiangsu were in the initially sustainable and basically sustainable stages; those in central Jiangsu were in the critically sustainable and initially sustainable stages; and those in northern Jiangsu were in the unsustainable and critically sustainable stages. This study proposed a scientific and effective evaluation method for cities along the Grand Canal to explore the efficient, sustainable use of land resources in the future. The evaluation framework constructed on this basis can serve as an important reference for urban governance and is expected to guide the sustainable use and development of land resources for other cities of the same type.

Spatiotemporal pattern and multi-scenario simulation of ecological risk in mountainous cities: a case study in Chongqing, China.

Scientific descriptions and simulations of the ecological risks in mountainous areas can promote the sustainable use of land resources in these areas and improve the reliability of decision-making for ecological risk management. Taking Chongqing, China, as an example, we constructed a landscape ecological risk (LER) evaluation model based on land use data from 1995 to 2020 and analysed the spatiotemporal evolution characteristics of the LER pattern. Moreover, we coupled the patch-generating land use simulation (PLUS) model and multi-objective programming (MOP) method and input multiple scenarios (inertial development, ID; economic priority development, ED; ecological priority development, PD; and sustainable development, SD) to simulate the ecological risk pattern in 2030. The model coupling the "top-down" and "bottom-up" processes obtained optimal land use patterns in different contexts, and it was used to perform a spatially explicit examination of LER evolutionary trends in different contexts. The results showed that LER evolution in Chongqing has had obvious stage characteristics. The high-risk area decreased significantly under various constraints, including topographic, economic, and other constraints, and the distribution showed a trend of high in the west and low in the east. The LER spatial clustering characteristics were highly coupled with the risk level pattern. The ED scenario presented the most severe risk, the PD scenario presented a moderate risk, and the SD scenario balanced the land demand for economic and ecological development and had a better land use structure and LER compared with the other scenarios. The coupled model proposed in this study helps to obtain the optimal land use structure and mitigate ecological risks, thus providing a scientific basis for future urban development.

Land Use Simulation and Landscape Ecological Risk Assessment on the Qinghai-Tibet Plateau

The land use and land cover pattern of the Qinghai-Tibet Plateau (QTP) is an important basis for the structure and function of the QTP ecological barrier. It is of great significance to simulate the land use pattern and landscape ecological risk of the QTP under future scenarios for the construction of the QTP barrier area and to promote the sustainable use of land resources. The QTP was selected as the study area. Based on the spatial pattern of land use in 2010 and 2020, the PLUS model was used to predict the land use patterns of the QTP in 2030 under the two scenarios of natural development and ecological conservation. The landscape ecological risk index was constructed to evaluate the past, present, and future landscape ecological risk of the QTP. The natural break point method was used to divide the landscape ecological risk index into five levels: lower ecological risk, low ecological risk, medium ecological risk, high ecological risk, and higher ecological risk. The results showed that: (1) Under the natural development scenario, the area of cropland, forestland, grassland, and unused land decreased continuously, while the areas of water and built-up land increased gradually. Under the ecological conservation scenario, the areas of forestland and grassland increased by 130 km2 and 2293 km2, respectively, compared with the natural development scenario. (2) Under the natural development scenario, the overall ecological risk of the QTP increased from 2010 to 2030, which showed that the proportions of lower ecological risk area decreased, while the proportion of medium and high ecological risk area increased. Under the ecological conservation scenario, compared with the natural development scenario, the area of lower, low, and high ecological risk increased by 4044 km2, 2484 km2, and 6401 km2, respectively, while the areas of medium and higher ecological risk decreased by 6333 km2 and 6597 km2, respectively.

Current Status and Development Trend of Soil Salinity Monitoring Research in China

Soil salinization is a resource and ecological problem that currently exists on a large scale in all countries of the world. This problem is seriously restricting the development of agricultural production, the sustainable use of land resources, and the stability of the ecological environment. Salinized soils in China are characterized by extensive land area, complex saline species, and prominent salinization problems. Therefore, strengthening the management and utilization of salinized soils, monitoring and identifying accurate salinization information, and mastering the degree of regional salinization are important goals that researchers have been trying to explore and overcome. Based on a large amount of soil salinization research, this paper reviews the developmental history of saline soil management research in China, discusses the research progress of soil salinization monitoring, and summarizes the main modeling methods for remote sensing monitoring of saline soils. Additionally, this paper also proposes and analyzes the limitations of China’s soil salinity monitoring research and its future development trend, taking into account the real needs and frontier hotspots of the country in related research. This is of great practical significance to comprehensively grasp the current situation of salinization research, further clarify and sort out research ideas of salinization monitoring, enrich the remote sensing monitoring methods of saline soils, and solve practical problems of soil salinization in China.

Study on Soil Erosion Driving Forces by Using (R)USLE Framework and Machine Learning: A Case Study in Southwest China

Soil erosion often leads to land degradation, agricultural production reduction, and environmental deterioration, which seriously restricts the sustainable development of regions. Clarifying the driving factors of soil erosion is the premise of preventing soil erosion. Given the lack of current research on the driving factors/force changes of soil erosion in different regions or under different erosion intensity grades, this paper pioneered to use machine learning methods to address this problem. Firstly, the widely used (Revised) Universal Soil Loss Equation ((R)USLE) framework was applied to simulate the spatial distribution of soil erosion. Then, the K-fold algorithm was used to evaluate the accuracy and stability of five machine learning algorithms for fitting soil erosion. The random forest (RF) method performed best, with average accuracy reaching 86.35%. Then, the Permutation Importance (PI) and the Partial Dependence Plot (PDP) methods based on RF were introduced to quantitatively analyze the main driving factors under different geological conditions and the driving force changes of each factor under different erosion intensity grades, respectively. Results showed that the main drivers of soil erosion in Chongqing and Guizhou were cover management factors (PI: 0.4672, 0.4788), while that in Sichuan was slope length and slope factor (PI: 0.6165). Under different erosion intensity grades, the driving force of each factor shows nonlinear and complex inhibitory or promoting effects with factor value changing. These findings can provide scientific guidance for the refined management of soil erosion, which is significant for halting or reversing land degradation and achieving sustainable use of land resources.