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Cultivated land degradation has seriously threatened to the national food security and sustainable land use. Among them, the sustainability of cultivated land can decrease or even completely lose, when it is subjected to the external disturbance. This temporal and spatial evolution can represent the cultivated land quality and ecological degradation. Significant mutual feedback between them can also impact the cultivated land degradation. It is crucial to clarify the mechanisms of cultivated land degradation and governance strategies, in order to ensure the national food security and sustainable utilization of cultivated land. Most existing studies have been focused on the evaluation and monitoring of cultivated land degradation. However, it is still lacking to consider the "comprehensive" interaction between the quality and ecological degradation of cultivated land. Furthermore, it is a high demand to clarify the influencing factors and mechanism of cultivated land degradation for the effective countermeasures. In this study, a novel system was constructed to measure the cultivated land degradation from the mutual feedback perspective of quality and ecology. Shenyang City in the typical Liaoning Plain area was also selected as the research area. The spatiotemporal characteristics, influence mechanisms and governance strategies of cultivated land degradation were explored using principal component analysis, objective weighting, exploratory regression, geographical weighted regression, quantile regression, and fuzzy data set comparison. The results show: 1) The proportion of cultivated land quality degradation was 35.31% in the study area, indicating a "strong east, weak west" spatiotemporal pattern; The proportion of cultivated land ecological degradation was 79.10%, with the spatiotemporal pattern of "strong north, weak south"; According to the quality and ecological mutual feedback, the proportion of cultivated land degradation was 37.80%, indicating a “strong north and south, weak middle” spatiotemporal pattern. 2) The temperature, vegetation coverage, urbanization, irrigation capacity and environmental pollution were the key natural conditions and socio-economic factors, leading to the degradation of cultivated land in the study area. The spatial heterogeneity was found in the effects of these factors on cultivated land degradation in different regions. There were the non-stationarity effects of development stages on the cultivated land degradation. Different structural configurations were formed to synergistically affect the cultivated land degradation. There were the regional, periodical, and structural influence mechanisms of cultivated land degradation. 3) According to the intensity of cultivated land degradation in the different regions, the different influencing factors and the action path of multi-factor combination, the graded and zonal protection of cultivated land was established to utilize and control the multi-factor concurrent collaborative governance and security path. The impact mechanism of cultivates land degradation was obtained from the perspective of quality and ecological mutual requirements. The finding can provide the policy reference for the accurate, efficient and collaborative management of degraded cultivated land. The synchronous quality and ecological environment of cultivated land can be expected to resist external adverse factors. [ABSTRACT FROM AUTHOR]

Land use in Hunan Province can share the common challenges on land space protection and development in China. The multifunctional land can be expected to solve the shortage and weak functionality of land resources. Taking Hunan Province as the research object, this article aims to construct a multifunctional evaluation index system using the land use multifunctional mechanism of "element structure space function". Land use multifunctional level was evaluated using entropy and TOPSIS, according to the spatial perspective of "Production-living-ecosystem". At the same time, spatial analysis was used to clarify the evolution characteristics of land use patterns in the region from 2000 to 2020. For example, the land use spatial transfer model and land use dynamic degree were then selected using ArcGIS software. Finally, a systematic investigation was made to explore the dynamic relationship between the evolution of land use spatial pattern and functional transformation using the dual perspective of "space+function". The results show that there were significant fluctuations in the spatial pattern of land use in Hunan Province from 2000 to 2020, where the production and ecological spaces were ever shrinking to expand the living spaces; Among them, the major characteristics were attributed to the significant expansion of living space and frequent conversion between production and ecological space. The main factors were obtained on the spatial fluctuations and reorganization of land use. 2) The regional distribution pattern and production space were distributed mainly in the central area of Changde, Yiyang, and Yueyang in the northern part of the province, as well as the border of Hengyang, Loudi, Shaoyang, and Yongzhou in the central part; The living space was distributed in the core distribution area centered around the Changsha Zhuzhou Xiangtan urban agglomeration and the central urban areas of each city; The ecological space shared the widest distribution area, particularly in the hilly and mountainous areas of the western and southwestern parts of the province, as well as in the Dongting Lake water area located in the northern part of the province; There was the more severe variation in the land use pattern evolution of the surrounding Changsha Zhuzhou Xiangtan area, followed by the mountainous areas on the east, west, and south sides; The dynamic degree results show that there was an upward trend for the overall dynamic change rate of land use. 3) The level of land use in the "Production-living-ecosystem" functions showed an increasing trend per year, with the highest ecological function score and the most significant changes, followed by the production function. Furthermore, the level of land use tended to stabilize during fluctuations. The living function was the lowest, indicating an increasing trend each year; The horizontal differences among regions were shifted from the low to high level relative equilibrium. 4) There was a significant correlation between the land use spatial pattern and functional transformation, especially in the temporal patterns. Finally, a beneficial attempt was made to explore the relationship between them using the multifunctional mechanism of "space+function" in land use; Therefore, it is necessary to further combine the land multifunctional measurement under the "one to many" mechanism, in order to more accurately identify the interrelationships among the "three living" spaces and functions [ABSTRACT FROM AUTHOR]

[Objective] To explore the trade-off and synergistic relationship between land use and ecosystem services in Yidu City, and optimize this relationship through multi-scenario simulation.[Method]Multi-objective planning and patch generation land use simulation model (PLUS) were used to construct three future development scenarios.The land use structure, spatial layout and ecosystem service value of Yidu City under different scenarios in 2030 were evaluated using InVEST model. [Result] Under the scenario of low-carbon development, the land use structure of Yidu City was the most reasonable, the spatial layout was the most intensive, and the ecosystem service value was the highest. Compared to other scenarios, the low-carbon development scenario performed better in terms of coordination and sustainability between land use and ecosystem services. [Conclusion] The low-carbon development scenario provides the best coordination path between land use and ecosystem services in Yidu City. [ABSTRACT FROM AUTHOR]

Urbanization and cultivated land use have presented a complex and dynamic relationship. This study aims to reveal the coupling and coordination relationship between urbanization and cultivated land use ecological efficiency, together with the driving factors behind it. The statistical data was collected from the 88 prefecture-level cities (states and leagues) in the Yellow River Basin from 2005 to 2020. The comprehensive evaluation was then adopted to measure the urbanization development level using the SBM-Undesirable model, and the coupling coordination degree model. The cultivated land use ecological efficiency and the coupling coordination degree were achieved after evaluation. The results show that: (1) The development level of urbanization increased steadily, but there was a much more outstanding feature of spatial differentiation. The first echelon of urbanization was gradually distributed in the downstream coast of the Yellow River, the middle and upper reaches of the northern part of the Yellow River; The ecological efficiency of cultivated land use was significantly improved with the imbalance of "high in the middle and low in the surroundings" in the local areas. (2) It continued to rise the coupling coordination degree between urbanization and cultivated land use ecological efficiency. But there was no reach in the advanced level of coordination. The extreme situation of "high in the east and low in the west" in the spatial distribution gradually evolved into the polycentric "high in the middle and low in the surroundings" pattern of differences. The overall spatial differences were gradually narrowing to evolve into the "high in the middle and low in the surroundings" pattern. Two types of coupling coordination were the "high-high" and "low-low" agglomeration. Among them, the "high-high" agglomeration was concentrated mainly in the downstream areas, such as Shandong and Henan Provinces. While the "low-low" agglomeration was mainly concentrated in the upstream areas of Gansu Province. (3) There were the influencing factors on the coupling coordination degree between urbanization and cultivated land use ecological efficiency, such as the scale of cultivated land operation, the income level of farmers, the government's agricultural support, the elevation, the average annual precipitation, and the average annual temperature. There was a non-linear and two-factor enhancement of the interaction among the driving factors. Therefore, much effort should be continued to narrow the gap between the development level of urbanization and the cultivated land use ecological efficiency among regions. In addition, breakthroughs and upgrades should be promoted in the level of coordination between urbanization and the cultivated land use ecological efficiency. The demonstration and leadership were found in the "high-high" agglomeration areas. Finally, it is necessary to take the regional background as the primary determinant of urbanization development and arable land use. While the interaction and complementary enhancement of each factor can be fully considered to synergistically improve the coordinated development of regional urbanization and arable land use. [ABSTRACT FROM AUTHOR]

Cultivated land fragmentation is often considered to reduce agricultural productivity, leading to threatening food security. The pattern and drivers of cultivated land fragmentation can be expected to serve as an important prerequisite for scientific management. Taking Jiangsu Province as the study area, this study aims to assess the cultivated land fragmentation at the county level from four dimensions, including PD (patch density), AWMSI (area-weighted mean shape index), SHDI-S (Shannon's diversity index of area), and COHESION (patch cohesion index). A systematic analysis was made on the clustering features of cultivated land fragmentation in different dimensions using the K-means. MGWR (multiscale geography weighted regression) model was applied to explore the driving factors of cultivated land fragmentation in each county from five dimensions: topographic site, soil properties, urbanization, utilization intensity, and protection strength. The results showed that there were north-south differences in the cultivated land, where the PD and AWMSI were higher in the south than those in the north, the SHDI-S was higher in the north than in the south, and the COHESION was higher in the west. The four dimensions of the county-level cropland fineness index showed three types of clustering: Type A and Type B counties were located in the southern part of the province, both of which shared high patch density, irregular shape, and high area diversity. Among them, the Type A counties were higher connectivity of cultivated land than Type B; Type C counties shared lower patch density, regular shape, low area diversity, and high cropland connectivity, which were distributed mainly in the central and northern parts of the province. In addition, spatial heterogeneity was observed in the driving factors of cultivated land fragmentation in different types of regions. Differentiated fragmentation management should be adopted for the different regions. Among them, cultivated land fragmentation in the southern counties and districts (Type A and Type B) was mainly driven by natural factors (elevation, slope, and soil capacity). There were the more complex factors in the central and northern counties (Type C), including cropland allocation and urbanization. Cultivated land in the Type A counties exhibited a high density and irregular shape of patches, but a high degree of connectivity, which was a greater potential for management. Some considerations were given to promote the merging of adjacent cultivated land for large-scale production when the soil properties were similar in the topographic conditions. A low degree of contiguous cultivated land was observed in Type B counties, indicating the more complex driving factors are more difficult to manage. More attention should be paid to protecting the existing cultivated land for future urbanization. Cultivated land in Type C counties shared a low density and regular shape of patches, with the large cultivated land and continuous distribution. Cultivated land in Type C counties was the most affected by the topographic slope and protection. The central and northern regions were mainly plains with flat terrain and arable land, indicating the low potential for management. However, some attention should still be paid to regulating the use of cultivated land. The finding can provide a strong reference to managing the cultivated land fragmentation in Jiangsu Province. The cropland fine fragmentation model can also be optimized to develop the sustainable use of cropland. [ABSTRACT FROM AUTHOR]

In order to explore the relationship between land use and the occupational and the job-housing function of subway stations, residential passenger flow index and employment passenger flow index were proposed as site clustering indicators. Firstly, the subway stations were classified to describe the type of job-housing function of the station. Then, the spatial logistic regression model was constructed to analyze the influence of land use around the subway station on its job-housing function under the influence of spatial effect. The results show that compared to employment-oriented stations, residential-oriented stations exhibit a more significant spatial dependence, for each additional station of the same type around residential-oriented stations, the probability of forming such stations increases by 4. 1% . Taking comprehensive stations as a reference group, for residential concentration-oriented stations, for every additional educational or cultural or parking facility point of interest (POI) around them, the probability of forming such stations decreases by 2. 7% and 3. 2% . In contrast, for employment concentration-oriented stations, for every additional life service or accommodation-related POI around them, the probability of forming such stations decreases by 2. 1% and 0. 8%, facilitating their transformation into comprehensive stations. The research results can provide reference for station area land use planning or optimization strategies. [ABSTRACT FROM AUTHOR]

Landscape pattern is one of the most intuitive manifestations of land use change. In order to evaluate the evolution of land use and landscape pattern in Luoyang city, and then provide reference for land resource management and ecosystem protection in Luoyang City, based on the remote sensing monitoring data of land use in China from 2000 to 2020 and the PLUS model, the changes of land use type and landscape pattern under the inertia development scenario and ecological protection scenario in Luoyang City in 2030 were simulated and predicted. The results show that from 2000 to 2020, the land use types of Luoyang are mainly cultivated land, forest land and grassland, and the overall regional land use fluctuation is small, and land use is in the development stage. In 2030, under the inertia development scenario, the land evolution rate of Luoyang City is increased, and the ecological land use shows a shrinking trend. Under the ecological protection scenario, the expansion of construction land is limited, the ecological land area increased, and the regional ecological benefit increased significantly. [ABSTRACT FROM AUTHOR]

Based on the data of land use change and energy consumption in Liupanshui City from 2009 to 2018, land use type change and carbon emission effect were analyzed, and the inherent relationship between land use type change and carbon emissions was studied. The results showed that the land use types changed greatly during the study period, in which the garden land, water area and construction land increased, while the cultivated land, forest land, grassland and unused land decreased. In the past ten years, net carbon emissions showed an increasing trend, and carbon sink showed a declining trend, resulting in the carbon footprint pressure index and carbon emission risk index of Liupanshui City also showed an increasing trend. The spatial differences of carbon emissions in different periods of Liupanshui City were significant, and there were also significant differences in the spatial distribution of carbon emissions,the carbon emissions in Liupanshui City showed a high characteristic in the north. The correlation coefficient of carbon emissions caused by different land types was different in different years. The correlation degree of construction land and carbon emissions in each district (city) of Liupanshui City was close to that of the whole city, and construction land had the greatest impact on carbon emissions in Liupanshui City. [ABSTRACT FROM AUTHOR]

[Objective] The aims of this study are to explore the response of ecosystem service value (ESV) to land use change, and to improve the sustainability of ecosystem service function in central Guizhou. [Methods] In this study, urban agglomeration of central Guizhou was taken as an example. Statistical analysis and spatial autocorrelation method were used to assess the land use change and ESV spatial and temporal evolution characteristics of urban agglomeration of central Guizhou from 2000 to 2020, and the spatial pattern of land use and its ESV change under different development scenarios in 2030 was predicted by coupling with PLUS model. [Results] (1) The land use change in the study area from 2000 to 2020 was mainly manifested in the transformation of cropland and grassland to construction land and waters, and affected by the land use change, the ESV of the study area increased by 11.28 hundred million yuan from 2000 to 2020, showing a fluctuating upward trend, and the expansion of waters and construction land area was the main reason for the change of ESV in the study area. (2) The decrease area of ESV from 2000 to 2020 was mainly distributed in the center urban area with better economic development, and the increase area was mainly distributed near rivers, lakes and other waters. The spatial autocorrelation analysis showed that the high and low agglomeration areas in the study area were widely distributed and strongly clustered, with the high and high agglomeration areas mainly concentrated in the northwestern part of the study area and the low and low agglomeration areas mainly concentrated in the central part of the study area. (3) The ESV under the nature scenario, cropland protection and ecological protection scenarios in 2030 are 710.22 hundred million, 705.33 hundred million and 720.62 hundred million yuan, respectively, and the ecological protection scenario has an obvious positive effect on the growth of ESV in the study area. [Conclusion In the future. the urban agglomeration of central Guizhou can continue to strengthen the policy of returning farmland to forests to improve the value of ecosystem services in terms of ecological environment, and it should formulate a more reasonable and comprehensive development strategy in terms of urban development, which can take into account ecological protection while the economy develops. [ABSTRACT FROM AUTHOR]

[Objective] The aims of this study are to explore the topographic gradient effect of land use in the Hanjiang Ecological Economic Belt (HJEEB), and to provide scientific reference for the adjustment and optimization of regional land use patterns. [Methods] Based on land use and DEM data from 1990 to 2022, four terrain features, namely elevation, slope, relief amplitude and topographic index, were selected to analyze the terrain gradient effect of land use change in HJEEB by used methods such as land use distribution index(DI), information graph. [Results] The land use structure of the HJEEB was mainly composed of forestland and farmland, with an area proportion of over 54.59% and over 35.20%, respectively. In terms of space, there was a pattern of farmland dominated in the east and forest land in the west. From 1990 to 2022, the areas of forestland, construction land, and water areas increased while the areas of farmland and grassland decreased significantly. As the gradient level of each terrain increased, the distribution area and index of farmland, water area, and construction land gradually decreased. The area of forestland showed a trend of first increasing and then decreasing, while the DI continued to increase. The area and DI of grassland showed a trend of first increasing and then decreasing. The distribution advantages of farmland and forestland during the research period had expanded in the low to medium(IIII) and high to medium(III-V) levels of various terrain factors, respectively, with an increase in their DI ranging from 0.041 to 0.117 and 0.005 to 0.076. Except for a consistent decrease in the DI on the I-level gradient, the distribution advantages of grassland and water area on other gradients mainly expanded, with the most significant increase in the DI being relief amplitude level III (0.317) and topographic index level III (0.299), respectively. The distribution advantage of construction land showed an expanding trend on the I-level gradient, with DI increase of 0.056 ~0.689. During the research period, the land use information graph of the HJEEB was mainly stable. accounting for 81.39% of the study area. In addition, there were significant differences in the degree to which various types of land use information graphs were affected by terrain gradients. [Conclusion Affected by factors such as watershed terrain structure and land use policies (returning farmland to forests, etc.), the land use pattern has a significant topographic gradient effect in HJEEB, and the change of distribution advantage is relatively complex in the topographic gradient. Therefore, the territorial space development needs to adhere to the principle of adapting to local conditions in future in order to promote the sustainable development of land resources. [ABSTRACT FROM AUTHOR]

[Objective] The purposes of this study are to explore the spatiotemporal evolution characteristics and influencing factors of land-use carbon emissions at different spatial scales, and to provide a reference basis for formulating reasonable carbon emission reduction measures and realize the goal of 'dual carbon'. [Methods] The land-use carbon emissions in Guangzhou in 2000, 2005, 2010, 2015 and 2020 were measured at township scale and 1 km grid scale. GIS spatial analysis, spatial autocorrelation. exploratory regression and geographically weighted regression (GWR) model were used to explore the spatiotemporal evolution characteristics and influencing factors of land-use carbon emissions in Guangzhou. [Results] (1) At the two scales, the areas of medium and high carbon emission areas were gradually increasing, while the areas of negative carbon emission areas and low carbon emission areas were gradually decreasing. (2) The land-use carbon emissions in the region generally had strong positive spatial agglomeration characteristics, and the degree of agglomeration tended to strengthen. The high high agglomeration and low-low agglomeration units were dominant, and the distribution of low high agglomeration areas were sporadic and did not change much. (3) The local spatial agglomeration pattern also involved some changes; the distribution of high-high agglomeration areas was expanding gradually; the distribution of low low agglomeration areas were shrinking at township scale, but expanding slightly at 1 km grid scale. (4) Land use structure, investment level and population size had positive effects on land-use carbon emissions, while population density of 95.32% of township units had inhibitory effects. [Conclusion The level of land-use carbon emissions Guangzhou gradually increased and showed positive spatial agglomeration characteristics on the whole, and the impacts of various influencing factors on it were significantly different. The results of this study can provide the reference for Guangzhou to formulate precise carbon emission reduction measures. [ABSTRACT FROM AUTHOR]

[Objective] It reveals the spatial distribution of carbon flow and the key path of carbon element transfer in Bin County, grasps the existing problems of Bin County's Production-Living-Ecological (PLE) space ecological environment, and then provides theoretical support for the future low-carbon rural planning and land-use resilience planning and management decisions in Bin County area. [Methods] Bin County was taken as an example. The overall metabolic network model of rural carbon elements' was constructed to identify and master the evolution law of the PLE spatial pattern, to quantitatively measure the characteristics of carbon sources, carbon sinks and the spatial-temporal dynamic changes of carbon elements in Bin County. [Results] (1) The predominant use of land continued to be for cultivation, while other types of land use displayed varying degrees of change, impacting the ecological environment. (2) Bin County's expanding residential areas had resulted in an initial surge, followed by a decrease in overall carbon emissions. In 2010, carbon emissions of Bin County spiked to 3.07 times of their previous levels, marking a crescendo. In 2020. the emissions of Bin County decreased by 2.25 million tons. The increase in the carbon sink was associated with the alteration in the area of the ecological space. (3) The spatial distribution of high carbon sink and source density mainly concentrated in the central and western parts of Bin County. The cultivated land production space and urban living space were the key components of carbon transfer in the two periods, respectively, and the mutual carbon transfer between the two land uses was also the dominant transfer path in different periods. [Conclusion] The spatial distribution of carbon flow and key paths of carbon element transfer in Bin County mainly concentrate in the areas with rapid urbanization process, where the ecological environment has serious problems. In the future, land use elasticity planning can promote regional sustainable development by formulating sustainable rural low-carbon emission reduction strategy. [ABSTRACT FROM AUTHOR]

[Objective] The aims of this study are to simulate the change of ecosystem service value caused by land use change in karst region, to analyze the response relationship of land use change to ecosystem service value, and to provide scientific basis for regional sustainable development and ecological security protection. [Methods] Guizhou Province, a karst region with fragile ecological environment, was taken as an example. The PLUS model was used to predict land use under different scenarios based on three periods of land use data in 2000, 2010 and 2020, and to further analyze the characteristics of the changes in ESV under multiple scenarios in terms of spatial distribution. [Results] (1) Among the four preset scenarios, the cultivated land area and forestland area of the natural development scenario showed a large reduction trend, with a reduction of 101 676 hm and 208 481 hm, respectively. (2) Under the four preset scenarios, the 2030 ESV followed the order: dual cropland and ecological protection scenario for the study area (48 869.4 million RMB)> ecological protection scenario (48 852.4 million RMB) natural development scenario (48 643.5 million RMB)> cropland protection scenario (47 908,7 million RMB). (3) Under the four preset scenarios, the spatial distribution characteristics of ESV per unit area in the study area in 2020 and under multi-scenario simulation were relatively similar. However, the spatial distribution of its ESV under the natural development scenario significantly reduced in the area of high values. [Conclusion] ESV is closely related to land use change, and rational planning for future land use is the most direct reason for ensuring good ecological quality, and from the perspective of sustainable development, economic development under the scenario of arable land and ecological protection is the best mode of land use. [ABSTRACT FROM AUTHOR]

[Objective] The aims of this study are to investigate the soil infiltration patterns under different land uses in karst trough valley and to propose a suitable soil infiltration model for karst trough valley. [Methods] Four typical land uses (forest, grassland, cropland and orchard) in the karst trough valley were taken as the research objects to determine the differences in soil infiltration characteristics and influencing factors as affected by different land uses, and to evaluate the adaptability of three common infiltration models: Horton, Kostiakov and Philip, the in this area. [Results] (1) Soil bulk density, water content and electrical conductivity were markedly different among different land uses (p＜0.05). Soil bulk density (1.1 g/cm³), water content (26.9%) and electrical conductivity (75.43 mS/cm) in cropland were lower than those in other land uses. Soil bulk density (1.32 g/cm³) in orchard, water content in forest (35.02%) and electrical conductivity in grassland (164.6 mS/cm) were higher than those in other land uses, respectively. (2) The infiltration process of different land use types showed rapid decline, slow decline and stabilization. (3) There were differences in the fitting results of Horton model, Kostiakov model and Philip model for different land use modes in karst trough valley. Horton model had the best results, with the fit R² reaching 0.922～0.951, and Philip model had the worst results, with the fit R² ranging from 0.754 to 0.908. (4) The pH value was highly significantly positively correlated with initial infiltration rate and average infiltration rate (p＜0.01) and significantly positively correlated with stable infiltration rate (p＜0.05); 0.05～0.25 mm and ＜0.05 mm fractions of micro-aggregates were significantly positively and negatively correlated with stable infiltration rate and average infiltration rate, respectively (p＜0.05). The multiple linear regression model showed that soil bulk density, water content and ＜0.05 mm fraction of micro-aggregates were the main factors influencing infiltration rate, which had an inhibitory effect on infiltration. [Conclusion] Cropland has better infiltration performance among different land uses, and the Horton model is more suitable for modeling soil infiltration in karstic troughs and valleys. The results of the study can provide a scientific basis for the assessment of soil infiltration performance and vegetation allocation in karst trough valley areas. [ABSTRACT FROM AUTHOR]

[Objective] The aims of this study are to analyze the runoff and sediment under different land use types and slopes in the loess hilly area of western Henan, and to provide scientific basis for quantitative evaluation of soil erosion and comprehensive prevention of soil erosion. [Methods] Based on the observation data of 12 runoff plots from 2011 to 2020 at the monitoring site of soil and water conservation in Hugou small watershed, Songxian County, Henan Province, the pattern of runoff and sediment under different land use was revealed. Correlation analysis was used to detect the relationship between rainfall characteristics, slope, land use, runoff and sediment yield. [Results (1) Compared with bare land plot, grassland plot had the greatest effect on runoff and sediment reduction. The average annual runoff reduction effect of grassland was 78.6%~85.9%, and the maximum sediment reduction effect was 100%. The runoff reduction effect of forestland was 32.9%~51.3%, and the sediment reduction effect was 55.3%~78.9%. (2) Runoff and sediment in each runoff plot and the slope were closely related. There was no significant difference between the runoff and sediment on the slopes of 10° and 15°, however, it increased significantly on the slope of 25°. In addition, with the increase of slope gradient, the soil and water conservation effect of forestland and grassland also reduced. (3) The correlation between runoff depth and maximum 30-minute rainfall intensity (130) and soil loss and rainfall erosivity were the most significant. [Conclusion] In areas where runoff and sediment localization observation is lacking in the loess hilly region of western Henan Province, rainfall process information can be used to estimate the runoff and soil loss under certain slope and vegetation conditions. [ABSTRACT FROM AUTHOR]

[Objective] This study aims to analyze the spatiotemporal dynamic evolution characteristics and driving mechanisms of impervious surfaces in the central Yunnan urban agglomeration, and to provide a theoretical basis for related research and assisting government and relevant departments in formulating urban agglomeration planning and development strategies, [Methods] GISD 30-meter impervious surface data from the central Yunnan urban agglomeration for the years 2000 to 2020 were utilized. Spatial analysis methods such as dynamic degree, standard deviation ellipse, quadrant analysis, and geographical detector were employed to reveal the spatiotemporal patterns of impervious surface changes and their driving mechanisms. [Results] (1) With respect to temporal scale evolution, over the past two decades, the overall expansion rate of impervious surfaces in the central Yunnan urban agglomeration exhibited a fluctuating trend characterized by decline-rise-decline, with an annual average expansion rate of 66.77 km². The annual average dynamic degree reached to 4.36%, indicating a continuous decline in the dynamism of impervious surfaces. The impervious surface area in the urban agglomeration expanded by 1 402.2 km² during this period, with a growth rate of 91.5%. (2) With respect to spatial scale evolution, the expansion of impervious surfaces within various cities of the central Yunnan urban agglomeration over the last two decades displayed significant spatial disparities. For instance. Kunming witnessed substantial expansion of impervious surfaces. while Chuxiong Prefecture exhibited comparatively minimal expansion. On the whole, the urban. agglomeration expanded towards the southern and southeastern directions, with the migration center remaining relatively stable, (3) With respect to directionality, the expansion of impervious surfaces in the central Yunnan urban agglomeration over the past 20 years showed a clear directional trend. primarily expanding in the northeast to southwest direction. The largest standard deviation ellipse area in year 2005 was marked, signifying the onset of rapid impervious surface expansion. Over the 20-year period, the center of impervious surface expansion remained relatively stable consistently shifting southward with relatively minor overall changes. (4) Analysis of driving mechanisms indicated that population factors had a significant impact on impervious surface expansion, whereas factors such as LAI, slope, precipitation, temperature. and NDVI had less significant effects. The interaction strength between population and other factors was notably stronger than that between other factors. Conclusion Over the past two decades, impervious surfaces in the central Yunnan urban agglomeration had continued to expand, exerting a significant influence on the resource and environmental carrying capacity of the urban agglomeration and the spatial land use pattern. To support the high-quality leapfrog development of the central Yunnan urban agglomeration, an emphasis on optimizing the spatial layout of impervious surfaces is crucial. [ABSTRACT FROM AUTHOR]

This study aims to clarify the spatiotemporal divergence of cultivated land use transformation in different functional areas for the sustainable management and utilization of land resources. The influencing factor was substituted to explain the transformation of cultivated land use. Taking all districts (counties) in Hubei Province as the research object, a systematic investigation was implemented to explore the spatiotemporal divergence of cultivated land use transformation in different main functional zones from 1995 to 2019. The data was collected from the socio-economic, natural geography, and agricultural production. The transformation of cultivated land use was determined from the perspectives of functional and spatial patterns. The research steps were as follows. Firstly, the functional and spatial values were calculated for the cultivated land use. Then the difference between the two periods was used to measure the degree of transformation of cultivated land use function and spatial transformation. The total degree of transformation was then measured on the cultivated land use. And then, kernel density estimation and spatial analysis were used to describe the spatiotemporal characteristics. The results indicated that: 1) There was a significant difference in the spatiotemporal divergence of functional transformation for the cultivated land use. A "V" shaped variation was observed as the first decreased and then increased over time. Different types of functional zones shared the negative transformation in the early and middle stages, while the positive transformation in the later stages. In terms of spatial distribution, there was a relatively severe degree of functional transformation in the mountainous areas of the western and a few areas in the Wuhan metropolitan area. While the rest areas were relatively gentle; The most severe level was found in the functional transformation of cultivated land use in the ecological function areas, followed by the Main Agricultural Production Areas, and finally the key development areas. 2) Spatial transformation of cultivated land use showed the trend of first increase, then decrease and then increase, like the "N" type over time; Different types of main functional areas shared the positive and negative interlacing transformation. The intensity of spatial transformation was obtained in the spatial distribution of cultivated land use. Among them, some districts (counties) in the Jianghan Plain and Wuhan metropolitan areas were stronger than those in the western and the rest regions. While the main agricultural production areas were stronger than the key development and the ecological function areas. 3) The total transformation of cultivated land exhibited an "M" shaped fluctuation over time; Different types of functional zones behaved the negative transformation in the early and middle stages, whereas, the positive transformation was in the later stages. There was a stronger intensity in the total transformation of cultivated land use in Jianghan Plain and some areas of the Wuhan metropolitan area, compared with the western. The findings can also provide the following suggestions. Different functional zones demonstrated significant heterogeneity, in terms of socioeconomic conditions, and resource endowments of cultivated land. Therefore, differentiated decision-making should be adopted to guide the transformation of arable land utilization in the needs of sustainable social and economic development in Hubei Province, China. [ABSTRACT FROM AUTHOR]

Forests are one oi the most important terrestrial ecosystems and play a crucial role in the construction oi ecological civilization. Understanding the changes in gross ecosystem product ( GEP) and its response to land use change in areas with unique advantages in iorest resources is oi great signiiicance for promoting sustainable development. We examined the GEP oi Zixi County oi Jiangxi Province. Based on the theory and method oi ecosystem value accounting, and on the basis oi the general indicator system ior regulating services ( water source conservation, soil conservation, oxygen supply, carbon iixation, climate control, flood regulation, water puriiication, air cleaning, species conservation) and the general indicator system ior cultural services ( landscape recreation, education), we added negative oxygen ions and health care indicators and introduced iorest ecosystem service correction coeiiicients to construct a GEP indicator system and method with unique advantages in forest resources. We evaluated the spatio-temporal variations of GEP in 2010, 2017 and 2020, and quantified the impact of land use/land cover change on GEP by means of elasticity index and value profit and loss analysis. The results showed that the GEP of Zixi County in 2010, 2017 and 2020 was 16.788 billion, 26.817 billion, and 38.407 billion yuan, respectively. Forests contributed the largest amount of GEP, followed by wetland, farmland, grassland, and town. During the study period, the added value of GEP mainly came from forest ecosystems. Land use change had an important impact on GEP. From 2010 to 2020, the total land use change area in the study area was 8501.88 hm2. The amplitude of land use change was grassland (-2811.17 hm2)>town (1428.06 hm2)>forest ( 1357.67 hm2 )> wetland ( 1031.05 hm2) > farmland (-1005.01 hm2). The absolute changes of various land use types were mainly occurred from 2017 to 2020. The elasticity index of each indicator on forest ecosystems was significantly higher than that of other ecosystems, indicating that GEP had the highest sensitivity to changes in forest area. The results of value profit and loss analysis showed that urban development had reduced GEP to some extent, while the protection of forest and wetland had increased GEP. From 2010 to 2020, the conversion of land use types in Zixi County led to an increase of 1.865 billion yuan in GEP, indicating that land use change in Zixi County had a positive ecological impact on the whole. Our results reflect the green development effect of Zixi County after becoming a national ecological civilization construction demonstration county, which could provide decision-making support for high-quality development, high-level protection and sustainable development and utilization of land resources in the future, and provide reference for other similar areas of GEP accounting. [ABSTRACT FROM AUTHOR]

Land use changes are the main cause for the changes of carbon storage, which is of great importance for maintaining regional carbon balance to make multi-scenario projections of future land use change and explore its impacts on carbon storage. In recent years, under the combination of natural factors and policies, with the land use changing significantly, carbon storage of the Weihe River Basin has also changed. Based on the PLUS-InVEST model, we assessed and predicted the spatial and temporal variations of ecosystem carbon storage in the Weihe River Basin and explored the impacts of land-use change. The results showed that land use distribution pattern of the Weihe River Basin did not change much from 2000 to 2020, which was characterized by the decreases of cropland area and the increases of the area of the remaining land use types. The main ways of land use type conversion were cropland to built-up land and inter-conversion of cropland, forest, grassland. Carbon storage in the Weihe River Basin showed an upward trend from 2000 to 2020, with a total increment of 15.31xl06 t. The areas with high carbon storage presented the characteristics of "northeast patch-western scatter-central and southern belt", while low carbon storage distributed in the Guanzhong Plain urban agglomeration located in the lower basin. Compared to 2020, carbon storage in the Weihe River Basin in 2030 would increase under the four scenarios. Carbon storage would increase the least under the economic development scenario, and the most under the ecological protection scenario. The variation of carbon storage in spatial distribution would be embodied in the staggered zone of cropland, forest, and grassland in the upper basin. The results could provide data support for land use management decisions and carbon storage enhancement in the Weihe River Basin. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of Soil & Water Conservation is the property of Bulletin of Soil & Water Conservation Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

According to Article 219 Paragraph 1 of the Land Law and Article 83 of the Urban Planning Law, after private land is expropriated, if the land use applicant does not start using the land within "one year after the completion of the expropriation compensation payment", or does not start using the land in accordance with the "period for approving the plan", the original land owner may apply to the municipality or county (city) land administration authority where the land is located to resume the expropriated land within 5 years from the day after the expiration of the period. The judgment of the Supreme Administrative Court (110) Shang Tzu No. 755 dealt with a dispute over the original land owner's application to resume his expropriated land, but his application was rejected due to late application. This article mainly explains the content of this judgment. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Soil & Water Conservation (1009-2242) is the property of Institute of Soil & Water Conservation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Soil & Water Conservation (1009-2242) is the property of Institute of Soil & Water Conservation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Soil & Water Conservation (1009-2242) is the property of Institute of Soil & Water Conservation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Soil & Water Conservation (1009-2242) is the property of Institute of Soil & Water Conservation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Rapid urbanization has exerted the considerable pressure on land resources and infrastructure, leading to urban sprawl. The delineation of urban growth boundaries (UGBs) has been one of the most crucial tools to manage and curb the urban sprawl. The delineation can also be optimized to alleviate the land-use conflicts for the sustainable urban development. The second-largest city in Shaanxi Province, Xianyang City is similar to the most middle-sized cities in China, indicating the rapid development with the land-use conflicts and ecological crises. In this study, the ecological protection areas of the high importance were delineated as the agricultural production and urban construction suitability areas, according to the "Dual-Evaluation" framework. The "top-down" policy constraints were served as the delineation of UGBs. Concurrently, the patch-generating land use simulation (PLUS) model was employed to conduct to meet the resource requirements and development potential in the study area. Future demands were forecasted and simulated for the land use. A "bottom-up" demand-driven approach was used to promote the rational use of land resources in the sustainable development of the environment. The delineation of UGBs was also in line with the local needs of actual development. Additionally, the erosion-dilation test was also employed to remove the noise points from the UGBs, particularly for the smoother and easier to manage. The results showed that: 1) The southern region was predominantly focused on urban development, where the area of 1 368.98 km² was designated as the urban construction. Meanwhile, the northern was prioritized the ecological protection, where the area of 3 853.04 km² was unsuitable for construction. 2) The PLUS model was used to simulate the urban construction land in 2040, which was 133.86 km² under the constraints of suitability evaluation. Compared with the natural development scenario, there was a significant reduction in the unused land area, along with an increase in the areas of arable land, forest land, and construction land, in order to facilitate the efficient use of land. 3) The erosion and dilation were integrated to exclude the unsuitable area for urban construction. The bottom-line UGBs was delineated as 3863.39 km²; The alternate UGBs was 852.28 km², which was composed of the suitable urban construction zones; The priority UGBs was 134.84 km² in the distribution range of urban construction land by 2040. The triple functional boundaries were established to promote the more compact and continuous urban pattern after morphological adjustments, thus guiding the direction of urban development. This approach can offer a novel perspective and scientific rationale to delineate the UGBs in the urbanization, in order to balance the development and protection. The conflicts among urban development, farmland protection and ecological conservation can also be determined to enable the coordinated development among population, resources and the environment. [ABSTRACT FROM AUTHOR]

In 2021, China achieved a comprehensive victory in the battle against poverty, and fully advancing the work of rural revitalization became the new focus of efforts. As an important component of rural areas, cultivated land is the material foundation and important support for rural revitalization.The multifunctional evaluation of cultivated land can help to reveal the multifunctional value of cultivated land, providing more reasonable cultivated land use and optimization measures by exploring the key areas and types of trade-offs and synergy between functions. It is of great significance for advancing the rural revitalization strategy and achieving the modernization of agriculture and rural areas. Taking Hebei Province as the research area, this paper constructs a functional evaluation index system to classify and evaluate cultivated land's production, ecological and living functions and subfunctions. Based on Spearman rank correlation and spatial autocorrelation, we examined the tradeoffs and synergy among different cultivated land functions, used the natural discontinuity classification method to divide cultivated land functions into secondary, tertiary and fourth-level classifications, compared the Spearman rank correlation coefficients between the functions in each group of data, determined regional differences in functional correlation, identified key functional trade-off and synergy regions as well as sub-functional role types, and finally cultivated land functional zones and core areas were divided. The results show that: (1) From 2010 to 2020, the production function of cultivated land in Hebei Province remained stable, the ecological function decreased, and the living function gradually improved. The three functions are all in a synergy relationship and apart from a weakening in the synergy between living and ecological functions from 2015 to 2020, the degree of synergy among other types of functions has gradually increased. (2) The key areas for functional synergy are mostly high-value areas. In the zoning based on the level of production function, the relationship between production function and ecological function shifted from low-value synergy to high-value trade-off. And in the zoning based on the level of living function, the synergy between the living function and the other two types of functions decreased as the living function improved. (3) There are more complex trade-offs and synergy among the subfunctions of cultivated land in Hebei Province. The synergy between landscape aesthetic subfunction and the three types of production subfunctions is the key to the synergy between production function and ecological function, and the synergy between landscape aesthetic subfunction and food security subfunction contributes the most to the synergistic relationship between ecological function and living function, and the synergy between grain production subfunction, large-scale production subfunction and food security subfunction is the key synergy between production function and living function. (4) Based on the values of cultivated land function, 6 types of cultivated land function advantage areas are divided, and 3 types of core functional areas are identified by combining spatial autocorrelation analysis. Our research analyzes the regional differences in trade-offs and synergy of cultivated land functions, identifies the important types of subfunctions that make significant contributions to functional synergy and divides cultivated land functional zones accordingly, to provide a more accurate optimization scheme for cultivated land use. [ABSTRACT FROM AUTHOR]

Tanzania is an important gateway for "the Belt and Road" initiative to reach the interior of Africa. It is faced with the ecological environment deterioration and the increasing threat of climate change. Based on the global 30-meter spatial resolution land cover data and multisource socio-economic and natural environment data, this study comprehensively uses research methods such as eco-environmental quality index, gravity center migration analysis, hot spot analysis, and geodetector to analyze the spatial differentiation characteristics of land use change and its ecological environment effects in Tanzania from 2000 to 2020. The results show that: ① The rate of land use change in Tanzania has slowed down, the area of cultivated land and artificial surface continued to increase, while the area of forest land and water body continued to decrease. The mutual transformation of cultivated land, forest land, grassland and shrubland was the main form of land use change. ②The eco-environmental quality index has been declining, with the central railway line as the boundary, showing the distribution characteristics of "high in the south and low in the north". The spatial pattern was relatively stable, and the gravity center was always within the scope of the capital city Dodoma. ③The spatial agglomeration characteristics of changes in eco-environmental quality were significant. The distribution range and agglomeration area of cold spots and hot spots were large from 2000 to 2010, and decreased from 2010 to 2020. The mutual transformation among cultivated land, forest land and grassland was the main type of land use transformation that affects the quality of ecological environment. ④ The contribution rate and significance of different influencing factors on eco-environmental quality in different regions were different. The influence of social and economic factors was greater than that of natural factors, while the synergy between natural factors was greater than that of social and economic factors. The population distribution has significantly strengthened the impact of various natural factors on the quality of the ecological environment. [ABSTRACT FROM AUTHOR]

Northern foothill of the Qinling Mountains region has been one of the unique ecological treasures in China, due to the rich and diverse ecological environment, as well as the complex terrain and variable climate. However, it is ever increasing impact of human activities on the local natural environment and ecosystems, as economic development and population growth. Severe challenges have posed on the protection of the ecological environment. Consequently, it is urgent to investigate the ecological environment quality in the stability and sustainable development of the ecosystem. This study aims to assess the ecological sensitivity in the northern foothills of the Qinling Mountains using the driving-force-pressure-state-impact-response-management (DPSIRM) and patch-generating land use simulation (PLUS) models. Initially, 17 indicators were selected to evaluate the ecological sensitivity in 2010, 2015 and 2020, according to the DPSIRM framework. Furthermore, the PLUS model was employed to simulate the spatial distribution of land use from 2020 to 2030. Various scenarios were also considered to integrate the present ecological situation. Subsequently, the simulated and predicted data of land use was served as the key influencing factors to assess the ecological environment. The spatial distribution of ecological sensitivity was predicted in the study area in the future. The findings reveal that the ecologically sensitive regions within the northern foothills were primarily centered around the urban core, indicating the greater resilience to disturbance, as the distance increased from urban centers. Furthermore, the proportion of non-sensitive areas gradually increased from 9% to 26% between 2010 and 2020, with the highest share of low-sensitive zones in 2010 (38%), medium-sensitive zones peaking in 2015 (28%), and the highest proportion of low-sensitive regions in 2020 (30%). Notably, the proportion of extremely sensitive zones was remained relatively low and consistent (5%-10%), indicating an overall favorable trend of the gradual improvement in the ecological environment over time. Furthermore, the patterns of land use were primarily comprised the farmland, woodland, and grassland, according to some projections under three distinct scenarios in the period from 2020 to 2030. Therefore, the ecological preservation was aligned with development and prioritizing sustainable strategies, which was most closely with current ecological objectives. The spatial distribution of ecological sensitivity was obtained within the context of ecological protection. Pertinent measures can be concurrently implemented in distinct sensitive areas. A robust foundation can be offered for the whole development and sustainable utilization of the ecosystem. The findings can also provide the solid refence to preserve the stability and sustainable ecosystem, particularly for the rational allocation and utilization of production, living, and ecological zones within the Qinling region. [ABSTRACT FROM AUTHOR]

Cultivated land has been one of the most vital resources and environmental elements for the human survival. However, the purely administrative rigid control cannot effectively meet the needs of urban and rural residents for the multiple functions of cultivated land. It is a high demand to coordinate the conflict between the “three lines” of territorial space and the multi-functionality of cultivated land. In this study, the control zones of cultivated land were constructed to complement the rigid control and flexible guidance, in order to realize the efficient and multi-functional use of cultivated land resources. The example was taken as Guangxi Hechi municipal jurisdiction. Firstly, the LESA system was applied to evaluate the level of regional quality of cultivated land, in order to preliminarily obtain the permanent basic and general farmland zones; The circuit resistance theory and the least cost path (LCP) model were selected to construct the ecological security pattern, in order to delineate the ecological protection red line; The construction land expansion was analyzed using the Geo-detector model. The urban development boundary was obtained from the dynamic simulation of the land use situation in 2035 using the Mixed Compartmental Cellular Automata (MCCA) model. Four scenarios were identified under the “three lines” conflict area after basic evaluation. The amendment rules were formulated to classify the cultivated land. The results show that: 1) The overall quality of cultivated land was at a medium-low level, most of which were II, IV and V levels. The area of permanent basic farmland was initially delineated to be 795.46 km2, according to the threshold effect; 2) The preliminary delineation of permanent basic farmland was in the serious conflict with the ecological protection red line and the urban development boundary, with an area of 212.39 km². The conflicting areas were optimized to ultimately obtain a reasonable permanent basic farmland area (i.e., rigid control area); 3) The general farmland outside the rigid spatial scope was amended for the flexible guidance zone. Three kinds of multi-functional zones of cultivated land were coupled within the spatial scope (production-ecological, production-livelihood and ecological-ecological-livelihood compound utilization zone). In view of different control zones, the control idea of “rigid and flexible” was proposed for the cultivated land system. Differentiated control measures were emphasized in use control, such as “what can't be done”, “what can be done” and “how can be done”. The rigid and flexible zoning of cultivated land was greatly contributed to the Hechi municipal jurisdiction. More refined management of cultivated land was formulated to implement the multifunctional and sustainable use of cultivated land. In conclusion, the rigid and flexible spatial delineation of cultivated land can accurately support the effective implementation of spatial planning, in order to realize the win-win situation of territorial spatial planning and the protection of cultivated land resources. [ABSTRACT FROM AUTHOR]

Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shenzhen University Science & Engineering is the property of Editorial Department of Journal of Shenzhen University Science & Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Mining Magazine is the property of China Mining Magazine Co., Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Reservoir-type drinking water sources in the Pearl River Delta ensure a safe urban water supply; thus, land-use changes are important factors affecting these aquatic environments. In this study, we investigated the water source areas of medium and large reservoirs in the Pearl River Delta to determine the contributions and trends of land-use changes within reservoir drinking water source areas to the reservoir water quality. First, we analyzed dynamic land-use changes in reservoir-type water sources in the Pearl River Delta region from 1980 to 2020. We then used the gray relational analysis method to determine the relationship between land use and water quality changes. We analyzed changes in the main water quality factors in the Dajingshan Reservoir (Zhuhai) and determined the relationship between changes in land use and the reservoir water quality index over the past 20 years using correlation and redundancy analyses. The results indicate that paddy fields, dry land, forest land, and water areas were the main land-use types around reservoir-type drinking water sources in the Pearl River Delta. Although construction land and water areas expanded, paddy fields, dry land, and forest land areas decreased. The land transfer trend was mainly from forest and cultivated land to production and living land (e.g.1980-2020), construction land) and water areas. With the implementation of the policy, the aforementioned land-use transformation began to slow. Regionally, the risk sources of non-point source pollution in the study area gradually decreased, but still accounted for 9.48% of total land use in 2020. The water quality of reservoir sources in the Pearl River Delta improved; however, nitrogen pollution remains problematic. Gray relational analysis indicates that land-use changes and water quality were correlated (in order of decreasing strength): construction land > agricultural land > forest land. Non-point source pollution caused by land use remains an important influencing factor. The Dajingshan Reservoir water quality is seriously polluted, as the total nitrogen exceeded the standard during several months, and nitrogen and phosphorus pollution gradually increased over time. Nitrogen and phosphorus were the main pollutants in the reservoir. Big mountain reservoir redundancy, correlation, and partial least squares regression analyses indicate that the land use type and water quality index were correlated, forest land and the nitrogen/phosphorus water quality index were negatively correlated, and construction and agricultural land were significantly positively correlated, which had a positive effect on the total nitrogen concentration. The influence of land-use patterns on non-point source pollution remains an uncontrollable factor. The specific effects of land-use changes on water quality are complex; therefore, further modeling should investigate the mechanism by which the water supply quality is influenced to improve reservoir water quality, ensure the safety of the regional water supply, and provide support for ecological restoration measures in protected areas.

[Objective] To understand the variations in soil erodibility and nutrient content caused by different slope positions and land uses, and to discuss the influence of various factors on soil erodibility and nutrient status. [Methods] Soil and root samples were collected, and the Comprehensive Soil Erodibility Index (CSEI) and Comprehensive Soil Nutrient Index (CSNI) were calculated using a weighted sum method under different slope positions and land uses. [Results] (1) There were differences in both CSEI and CSNI among different slope positions. The highest value of CSEI was recorded on the slope crest (0.653) and the lowest value was at the bottom of the slope (0.275), while the highest value of CSNI was found on the slope crest (0.715) and the lowest value was at the top of the slope (0.341). (2) Differences in both CSEI and CSNI were observed among different land uses. The highest value of CSEI was observed in fallow land (0.617) and the lowest value was in forests (0.252), while the highest value of CSNI was found in forests (0.793) and the lowest value was in fallow land (0.322). (3) CSEI was significantly negatively correlated with clay content, sand content, root length density and aboveground biomass. It was also significantly positively correlated with silt content and soil bulk density. Soil bulk density had the greatest direct impact (0.26). CSNI was significantly positively correlated with clay content, sand content, root length density and aboveground biomass. It was also significantly negatively correlated with silt content and soil bulk density. Clay content had the greatest direct impact (0.45). There was a significant negative correlation between CSEI and CSNI. [Conclusion] Slope position significantly influences both CSEI and CSNI, emphasizing the importance of focusing on slope crests and mid-slopes in vegetation restoration efforts. Vegetation restoration in various geomorphic positions effectively reduces CSEI and enhances CSNI, with trees being more effective in controlling soil erosion.

[Objective] In order to clarify the law of sediment yield and sediment loss of different land use types under different rainfall types, and to evaluate the benefit of sediment reduction of different land use types under different rainfall types. [Methods] Based on the monitoring data of runoff and soil loss under natural rainfall conditions over 2015—2016 in 31 runoff plots located in the Loess Plateau of China the characteristics of sediment yield and loss in different land use types, including farmlands, abandoned lands, artificial grasslands, natural grasslands, shrublands and artificial forest lands were discussed. The efficiency of runoff and sediment reduction for each land use type under different rainfall types was determined. [Results] The runoff and soil loss of abandoned lands were the largest (30 mm, 86 t/hm2) and artificial forest lands were the smallest (8 mm, 24 t/hm2) under the annual rainfall scale, and there was no significant difference between other land use types. Through the application of duster analysis a total of 120 rainfall events were categorized into three distinct rainfall types based on criteria that included amount, duration, and maximum intensity of rainfall in a 30-minute period. That is, Rainfall Type I: characterised by moderate rainfall duration (749 min), moderate rainfall volume (35.4 mm), and moderate rainfall intensity (16.9 mm/h); Rainfall Type II: comprising short-duration rainfall (222 min), moderate rainfall volume (25.2 mm), and intense rainfall intensity (23.8 mm/h); Rainfall Type III: involving a long duration of rainfall (1 451 min), substantial rainfall volume (40.6 mm), but low intensity of rainfall (11.5 mm/h). When considering the impact of these types of rainfall within the given scale, the study observed the following trends, for the runoff coefficient, exhibiting Rainfall Type II > Rainfall Type III > Rainfall Type I, while for soil loss, exhibiting Rainfall Type II > Rainfall Type I > Rainfall Type III. The runoff coefficient of Rainfall Type I was significantly higher than that of other land use types, reaching 17.7%, which was 2.36 times that of artificial forest land. There were no significant difference in runoff coefficient under Rainfall Type II, and the average runoff coefficient was 19.9%. The runoff coefficient of abandoned lands, artificial grasslands, natural grasslands, and farmlands (average of 14.3%) was significantly higher than that of shrublands and artificial forest lands (averaging at 9.0%). The soil loss of famlands, artificial grasslands, shmblands and artificial forest lands under Rainfall Type II (3.94, 0.87, 1.06, 1.08 t/hm2) > Rainfall Type I (1.60, 0.60, 0.59, 0.63 t/hm2) > Rainfall Type III (0.09, 0.20, 0.06, 0.04 t/hm2). [Conclusion] In the Loess Plateau, the artificial forest land was the first choice to control soil and water loss effectively under the condition of medium-low rainfall intensity and medium-long duration rainfall, and the soil and water conservation effect of shrubland and grassland was better under short-duration heavy rainfall.

[Objective] The aims of this study are to explore the response of ecosystem service value to land use change and predicting future trends, and to provide scientific reference for land use pattern planning in the arsenic sandstone area. [Methods] Based on the remote sensing images of the four phases of sandstone area from 2000 to 2020, the change characteristics of LUCC and ESV in the past 20 years were analyzed based on GIS technology and ESV evaluation methods. The response of LUCC induced by ESV was revealed. The development trend of LUCC and ESV was predicted by using Markov model. [Results] (1) In 2000- 2020, the total area of LUCC remained unchanged, and the increase of construction land was the most obvious, with a total increase of 762.73 km² and a growth rate of 4.57%. The grassland decreased by 548.79 km² in total, with a reduction rate of 3.28%. (2) The overall level of ESV showed a downward trend, from 19 949.65 million yuan to 18 997.19 million yuan, a decrease of 4.78%, of which grassland ESV changed the most, decreasing by 746.29 million yuan, accounting for 78.35% of the overall decline rate. (3) ESV was positively correlated with the changes in grassland, woodland, cultivated land, water area and construction land, and negatively correlated with unused land. (4) It is predicted that the area of cultivated land, forest land, grassland and water area will decrease to 96.69%, 98.94%, 94.27% and 99.12% of those in 2020 in the next 10 years. Construction land and unused land will increase to 150.03% and 121.61%, and the overall ESV level in sandstone area will continue to decrease to 92.81%. [Conclusion] The areas of cultivated land, forest land, grassland, and water are decreasing, while the area of construction land and unused land will increase. ESV will continue to decrease, and there is a linear relationship between ESV changes and land use changes. In the future, the area of construction land will increase, and ESV will continue to decrease. Reasonably adjusting the area of construction land is beneficial for ecological construction and vegetation restoration and reconstruction in the sandstone area of the Yellow River Basin. [ABSTRACT FROM AUTHOR]

[Objective] The aims of this study are to explore the spatial and temporal evolution patterns of vegetation cover in the urban agglomeration of southern Sichuan, to analyze its driving mechanism, and to provide reference and decision-making basis for promoting ecological environmental protection and sustainable socioeconomic development in the upper reaches of the Yangtze River. [Methods] The vegetation cover was taken as the research object. The coefficient of variation and linear regression research methods were used to analyze the spatial and temporal evolution characteristics of the vegetation change in the urban agglomeration of south Sichuan from 2001 to 2021, and the geographic detector model was used to explore the influencing factors. [Results] (1) The overall condition of vegetation cover in the south Sichuan urban agglomeration was good, and the proportion of areas with vegetation cover of 0.4 or more was 71.74%. The change of vegetation cover was dominated by low fluctuation, accounting for 78.16%. The trend of vegetation degradation was significant, accounting for 8.89%. (2) The degree of influence of each driving factor on vegetation cover was ranked in descending order: elevation> land use type average annual temperature> slope population density > GDP > urbanization rate average annual evaporation average annual precipitation aspect. Among them, the explanatory power q-values of the first six factors were all greater than 16%, which were the main driving factors affecting the change of vegetation cover. (3) Any two-factor interactions were dominated by two-factor enhancement and nonlinear enhancement, in which the q value of the interaction between elevation and land use type was the largest, 0.369. (4) When the elevation was 1 200 to 1 400 m, the mean annual temperature was 12.15 to 15.16 °C, the slopes were 32° to 35°, the population density was less than 22.31 people/km², the GDP was 122 to 1 221 yuan/km2 and when the land use type was woodland, the vegetation was most suitable. [Conclusion] The overall condition of vegetation cover in the south Sichuan urban agglomeration from 2001 to 2021 was good, and topography, meteorological conditions and socioeconomic factors all had a significant impact on regional vegetation changes. [ABSTRACT FROM AUTHOR]

[Objective] The aim of this study is to explore the accuracy and applicability of different machine learning models for predicting the spatial distribution of surface soil organic carbon density (SOCD) with limited samples, which can provide a references for the study of watershed scale carbon pool in the Chinese Loess Plateau. [Methods] In this study, we compared the accuracy and stability of the predicted SOCD in topsoil (0-20 cm) by four machine learning models, namely Multiple Linear Stepwise Regression (SR), Random Forest (RF), Extreme Gradient Boosting (XGB) and Support Vector Machine (SVM), based on the limited measured samples in a sub-watershed of Yanhe River in the Chinese Loess Plateau. [Results] (1) Under the condition of limited samples, all models successfully and appropriately predicte the spatial distribution of SOCD, among which the SVM model has the best model performance, and the average RMSE, R² and MAE of 50 predictions is 0.74. 0.43 and 0.64, respectively. (2) The average SOCD of different land use types are consistent between measured and predicted values but shows significant difference among land use types. SOCD decreases in the order: shrubland forestland > grassland > cropland. The total organic carbon of cultivated land in the study area is 2.39×106t (0-20 cm). (3) The evaluation of feature importance shows that terrain factors, NDVI max, near-infrared surface reflectance (B5) and Brightness index have significant contributions to the accuracy of predictions. [Conclusion] Under the condition of limited samples, the machine learning model combined with controlling features can be effectively applied to the prediction of the spatial distribution of topsoil SOCD at the watershed scale in the Chinese Loess Plateau. [ABSTRACT FROM AUTHOR]

[Objective] Habitat quality is the potential of ecosystems to provide the necessary conditions for species survival and reproduction, and is the key to improving ecosystem functions. Studying the habitat quality of the Yangtze River Basin is of great significance for national major strategies such as green development of the Yangtze River Economic Belt and the protection of the Yangtze River. [Methods] Based on land use data from 1980 to 2018 in the middle and lower reaches of the Yangtze River, the InVEST model was used to study the spatiotemporal changes in land use change, habitat quality, and habitat degradation in the middle and lower reaches of the Yangtze River from 1980 to 2018. [Results] (1) As the main type of land use in the study area, woodland was decreasing, mainly turning to construction land and water area, which greatly reflected the driving effect of population growth, economic development and environmental protection on the change of land use structure. (2) The overall habitat quality of the study area was at a high level. showing a trend of low in the east and middle, and high in the south, which was consistent with the land use pattern that most of the cities along the Yangtze River in the east and middle of the study area were dominated by construction land, and the south was dominated by woodland and grassland. (3) In the study area, the degree of habitat degradation was higher in the central area and lower in the surrounding area. The change of the degree of habitat degradation showed an upward trend in time, and the areas where the degree of habitat degradation changes were more concentrated in space, such as the urban agglomeration along the river, urban and rural areas and other population agglomerations. [Conclusion] The habitat evolution in the middle and lower reaches of the Yangtze River is in a process of degradation. The process of urbanization makes a large number of woodland, grassland and cultivated land in land use turn to construction land, which leads to the continuous decline of habitat quality, especially the problem of the urban agglomeration. along the Yangtze River. We should develop construction land more reasonably and draw the ecological protection red line, gradually restore and improve the habitat quality of the middle and lower reaches of the Yangtze River, and make a positive contribution to the process of the Yangtze River protection. [ABSTRACT FROM AUTHOR]

[Objective] The aims of this study are to investigate the evolution of ecosystem service value (ESV) and its influencing factors urbanization in the Karst city cluster and to provide a scientific basis for regional eco-environmental protection ecological function zoning, and ecological compensation decision- making. [Methods] Based on the land use data of urban agglomeration of central Guizhou Province from 2000 to 2020, 16 drivers were selected from natural and socio-economic perspectives, and a Markov-FLUS model was constructed to simulate the land use pattern in 2030 under the scenarios of natural development and ecological constraints. Then, the modified ESV coefficients were used to assess the spatial and temporal evolution of ESV and analyze the factors influencing the spatial differentiation of ESV using Geo detector. [Results] (1) The artificial surface seriously encroached on cropland (53%), forest land (12%), and grassland (10%) from 2000 to 2020. Under the ecological constraint scenario, significant nature reserves were effectively protected, and the artificial surface increased by 55 500 hectares, with a slower growth rate. (2) The ESV as a whole showed a trend of rising and then falling, with regulating services (71.08%)> supporting services (23.59%) cultural services (4.51%) supplying services (0.82%). The value of ESV in 2030 under the natural development scenario was 59.211 billion yuan, and that was 58.906 billion yuan under the ecological constraint scenario. (3) The explanatory power of ESV spatial differentiation factors followed the order: area of districts and counties (0.79)>value-added of agriculture, forestry, animal husbandry and fishery (0,51)> value-added of primary industry (0.50)>GDP (0.41)>GDP per capita (0.30)>area of built- up area (0.09)>resident population (0.04). The area of districts and counties, value-added of agriculture, forestry, animal husbandry and fishery, and value-added of primary industry were significantly and positively correlated with ESV, and GDP was significantly and positively correlated with ESV. The area of districts and counties, value-added of agriculture, forestry, animal husbandry and fishery, and value-added of primary industry were significantly positively correlated with ESV, and GDP was significantly negatively correlated with ESV. [Conclusion Regional ecosystem services are mainly regulating services, and water and woodland ecosystems have a more significant impact on the overall ESV, which is the center of gravity of regional environmental protection and ecological construction. [ABSTRACT FROM AUTHOR]

[Objective] The temporal and spatial changes of land use and carbon storage in the Pearl River Basin in the past 20 years and the next 10 years were analyzed in order to provide a reference for the optimization of land use pattern and ecosystem carbon sequestration management in the Pearl River Basin. [Methods] Based on the land use data of 2002, 2012, and 2022, this paper analyzed the changes of land use types, used the PLUS model to simulate the land use pattern under the natural development scenario, cultivated land protection scenario and ecological protection scenario in 2032, and used the InVEST model to evaluate the changes of ecosystem carbon storage under the three scenarios. [Results] The land types in the Pearl River Basin have changed greatly in the past 20 years, and the one-way conversion of cultivated land to construction land and the two-way conversion between cultivated land and forest land were the main characteristics of land use change in the Pearl River Basin. During the same period, the carbon storage of terrestrial ecosystems showed a downward trend as a whole, with a decrease of 0.52%. The carbon storage projection in 2032 shows that the carbon storage under the ecological protection scenario is significantly higher than that under the cultivated land protection scenario and the natural development scenario, which are 4.81×106 and 10.22×106 t higher, respectively. [Conclusion] Therefore, when formulating land use planning in the future, decision-makers should consider the balance between economic development and ecological protection, strengthen the concept of ecological protection and green development in river basins, increase the function of land carbon storage, and help achieve the “double carbon” goal and regional sustainable development.

[Objective] This study was aimed to estimate the amount of water conservation in Shaanxi Province. [Methods] The InVEST model and PLUS model were coupled to calculate the water conservation amount in Shaanxi Province from 2000 to 2020 and predict the water conservation amount under land use changes in the future in 2030. [Results] The average water conservation amount in Shaanxi Province from 2000 to 2020 was 132.25 mm, with a spatial distribution characteristic of gradually increasing water conservation from north to south. From the perspective of vegetation types, forest land was the main body of water conservation in Shaanxi Province. The average annual water conservation amount was 199.55×108 m3. From the administrative region, Ankang City had the largest water conservation amount(308.96 mm). The total amount of water source conservation in 2030 will be 285.16×108 m3 and 8.68×108 m3 less than that in 2020. [Conclusion] The water conservation amount of Shaanxi Province will show a slight downward trend from 2020 to 2030 in the future.

[Objective] The Yangtze River is an important ecological security barrier in China. Analyzing the spatial-temporal changes of ecosystem services and the driving force of land use change in the Yangtze River Basin is conducive to the coordinated development of ecology and economy in the region. [Methods] Based on remote sensing data from 2000 to 2020, the RUSLE model and the InVEST model were used to calculate the amount of soil retention, water yield, and carbon sequestration in the Yangtze River Basin. The Sen trend method and hotspot analysis method were used to analyze changes in ecosystem services. Partial correlation analysis was used to analyze the tradeoff-synergy relationships between services, and the reasons for change in ecosystem services were analyzed from the perspective of land use change. [Results] (1) From 2000 to 2020, the trends of change of average annual soil retention, water yield, and carbon sequestration in the basin were about 1.75 t/(hm2·a), -1.33×103 m3/(km2·a), and 1.62 gC/(m2·a). Except for water yield, which showed a decreasing trend in some areas, other services showed an increasing trend in most areas. The overall area of ecosystem services hotspots was expanded, especially those dominated by carbon sequestration and water yield services. (2) Soil retention and water yield were mainly in an insignificant tradeoff relationship, soil retention and carbon sequestration were mainly in a significant synergistic relationship, and carbon sequestration and water yield were mainly in an insignificant synergistic relationship. (3) The conversion from cropland to forestland had a greater impact on soil conservation services, the conversion from cropland to grassland had a greater impact on carbon sequestration services, and the conversion from grassland to cropland had a greater impact on water yield services. (4) Soil retention, water yield, and carbon sequestration services tended to be synergistic when cropland was converted to forest and grass areas, and tended to be tradeoff when the forest and grass areas were turned to cropland. [Conclusion] The ecosystem services in the Yangtze River Basin have improved in general. The increase in forest and grass area in land use change had a positive effect on the improvement of ecosystem services and the coordinated development between services. The game between land development and ecological protection has led to dynamic changes in ecosystem services. Considering the importance of regional economic development, it is necessary to balance development and protection, and achieve green and sustainable development.

[Objective] To quantitatively study the relationship between land use change and ecosystem service value in Sichuan section of the upper reaches of the Yellow River in the past 20 years, and to evaluate the effect of comprehensive ecological management in this section, so as to provided a basis for improving ethnic regional spatial planning, ecological environmental protection and management, and promoted the high-quality development of the Yellow River Basin. [Methods] Using the land use data of the upper reaches of the Yellow River in Sichuan in 2000, 2010 and 2020, land use change was analyzed based on land use dynamic attitude and land use matrix, and the economic value of the ecosystem service value equivalent per unit area of the terrestrial ecosystem in China was revised. The effects of land use change on the ecosystem service value in the upper reaches of the Yellow River from 2000 to 2020 in Sichuan were quantitatively studied. [Results] (1) From 2000 to 2020, the land use area of forest, desert, wetland and water system in the upper reaches of the Yellow River in Sichuan showed an increasing trend, while the land use area of cultivated land, shrub, grassland and glacial and snow in the upper reaches of the Yellow River showed a decreasing trend, and the land use change in 2010—2020 was more significant than that in 2000—2010. (2) The ecosystem service value of the upper reaches of the Yellow River in Sichuan in 2000, 2010 and 2020, was 1.27×1010, 2.51×1010, 3.92×1010 yuan, respectively, showing an increasing trend. The sensitivity analysis showed that the analysis results were reliable. Amongall land use types, grassland made the most significant contribution to total ecosystem value, and the contribution rate of grassland ecological service was 93.90% and 72.90% in 2000—2010 and 2010—2020, respectively, followed by wetland and forest land. (3) In the study area, the value of each individual ecosystem service showed an increasing trend in the past 20 years, and the sub-value of regional ecological service function was regulatory service>support service>supply service>cultural service. Among the 11 individual functions, the significant service value was climate regulation, hydrology regulation, soil conservation and biodiversity. The sum of the four items accounted for more than 69.50% of the total value. Land use change in the upper reaches of the Yellow River in Sichuan affected the changes of regional ecosystem service value, and grassland was the most significant, followed by wetland and forest land. [Conclusion] The results showed that the results of ecological governance in the past 20 years have been gradually enhanced, and the ecological environment has continuously improved.