[Objective]This study aims to scientifically delineate land use functional zones in Anhui Province,identify the key driving factors of landscape ecological risk,and reveal the spatiotemporal evolution characteristics and spatial conflict patterns of ecological risk,providing scientific support for regional ecological security and territorial space planning.[Methods]Taking Anhui Province as the study area,a land use functional zoning scheme was developed by integrating the morphological spatial pattern analysis(MSPA),Conefor,and minimum cumulative resistance(MCR)models and applying the resistance threshold method.On this basis,This study combines the XGBoost model with the SHAP interpretation method to quantitatively analyze the effects of topographic conditions,climatic factors,and socio-economic factors on landscape ecological risks.[Results]1)According to land use functions,Anhui Province can be divided into three core areas,among which the ecological protection core area accounts for 30.96%,the agricultural production core area accounts for 35.52%,and the construction and development core area accounts for 33.52%.Spatially,the three areas are respectively concentrated in the southern Anhui region,the northern Anhui region,and the urban agglomeration in central Anhui.2)From 2000 to 2020,the overall landscape ecological risk in the region has been continuously intensifying,with the proportion of areas with high and very high risks increasing from 16.95%to 32.81%.In terms of spatial distribution,low-risk zones largely coincided with ecological protection zones,while high-risk zones were concentrated in construction development zones.3)The analysis of influencing factors showed that topographic factors exerted the greatest influence on the provincial risk pattern.Climatic factors were the dominant factors in ecological protection and construction development zones,whereas socio-economic factors had the most significant influence on risk in agricultural production zones.4)Ecological risk conflicts within the province were significant,with relatively high-and high-conflict zones accounting for 30.78%,mainly distributed in cities such as Anqing and Hefei.[Conclusion]Landscape ecological risk in Anhui Province shows an intensifying trend.The province is influenced by topographic factors,while different zones are driven by climatic and socio-economic factors,and high-risk zones are concentrated in construction development core zones.It is recommended to implement differentiated management strategies based on functional zoning,focusing on mitigating spatial conflicts in areas such as Anqing and Hefei to improve regional ecological security.The findings provide a scientific basis for the synergistic governance of territorial space planning and ecological risk.
[Objective]This study aims to reveal the spatiotemporal differentiation patterns of cultivated land landscape from the provincial scale to economic zones in Sichuan Province,and to quantify the contributions and interactive effects of natural and socio-economic factors on landscape pattern changes.[Methods]Based on multi-source remote sensing and geographic information system(GIS)technology,a spatiotemporal evolution model of landscape ecology was constructed on the ArcGIS and Fragstats platforms.Combined with the geodetector and entropy weight-TOPSIS method,the spatial heterogeneity characteristics and driving mechanisms of cultivated land landscape patterns in Sichuan Province and its five major economic zones from 2000 to 2022 were systematically analyzed.[Results]1)From 2000 to 2022,the cultivated land in Sichuan Province generally showed a trend of scale reduction,fragmentation intensification,and connectivity decline.The area of dryland decreased by 13 961.0 km²,with a higher reduction rate than that of paddy fields.The number of patches increased sharply,and landscape dominance continued to weaken.2)The five major economic zones exhibited significant differences.The Chengdu Plain Economic Zone showed quantity reduction and shape fragmentation.The Western Sichuan Economic Zone presented paddy field expansion and dryland shrinkage.Both paddy fields and dryland in the Northeast Sichuan Economic Zone decreased by more than 19%.The area of dryland in the Southern Sichuan Economic Zone decreased by 11.58%,with local retention of core cultivated areas.The area of dryland in the Panxi Economic Zone decreased by 27.49%,with the highest degree of fragmentation.3)In terms of driving mechanisms,the interactions between natural and socio-economic factors were dominated by two-factor enhancement and nonlinear enhancement effects.Among them,population density had the highest interactive explanatory power(0.97).The influence of human-driven factors generally increased across regions.Economically developed areas were mainly driven by urbanization and industrialization,ecologically sensitive areas were dominated by natural constraints and policy regulation,and traditional agricultural areas were trapped in a cycle of agricultural decline and population loss.[Conclusion]The findings of this study can provide a theoretical basis for the construction of an ecological security pattern for cultivated land and differentiated management strategies in Sichuan Province,thereby supporting the sustainable use of cultivated land landscapes and the process of territorial spatial governance.
[Objective]This study aims to investigate the morphological change process of scour holes at the headcut of ephemeral gullies on slopes with typical herbaceous communities and their main controlling factors.[Methods]Field runoff scouring experiments were conducted on slopes covered by three typical herbaceous communities in the loess hilly-gully region(Stipa bungeana,Lespedeza davurica,and Artemisia gmelinii).Close-range photogrammetry was applied to monitor morphological change processes of scour holes.[Results]1)Significant differences in root mass density and soil properties were observed among different herbaceous communities.In the topsoil layer(0～0.2 m),the Artemisia gmelinii community exhibited significantly higher root mass density,root length density,total porosity,saturated water content,and aggregate mean weight diameter than the other two communities,while soil bulk density,cohesion,and penetration resistance showed the opposite pattern.2)Herbaceous communities significantly affected the morphological characteristics of scour holes and their change processes.Morphological parameters,including width,height,depth,area,volume,shape factor,and depth-to-diameter ratio,showed fluctuating variations with scouring duration,following an increase-decrease-increase trend.Significant differences in morphological development of headcut scour holes at gullies were observed among different herbaceous communities,with the slowest development in the Artemisia gmelinii community,followed by Lespedeza davurica and Stipa bungeana.3)Pearson correlation and partial least squares(PLS)analyses showed that root mass density,root length density,total porosity,saturated water content,and aggregate mean weight diameter significantly affected scour hole depth.PLS structural equation modeling(PLS-SEM)indicated that vegetation root traits and aggregate mean weight diameter were key factors affecting scour hole depth development,with total effects of-0.65 and-0.53,respectively.Vegetation roots significantly increased soil aggregate stability,thereby inhibiting scour hole development.[Conclusion]The findings provide important theoretical support for understanding mechanisms by which vegetation restoration influences headward erosion in ephemeral gullies.
[Objective]This study systematically characterizes the spatial correlation network of new-type urbanization and examines its impact on territorial spatial utilization efficiency,aiming to provide theoretical support and references for improving new-type urbanization policies and promoting the efficient utilization of territorial space.[Methods]Based on panel data from 21 prefecture-level cities in Guangdong Province from 2005 to 2023,social network analysis was used to characterize the spatial correlation network of new-type urbanization.A super-efficiency model(SBM)was applied to measure territorial spatial utilization efficiency,and a panel data-based fixed effects model was constructed to empirically validate the impact of the spatial correlation network of new-type urbanization on territorial spatial utilization efficiency.[Results]1)The spatial correlation network of new-type urbanization in Guangdong Province formed a core-periphery stratification structure,with the Pearl River Delta as the core area and the remaining regions as peripheral areas.2)The network relevance score remained at 1 throughout the study period,and no island nodes were observed.Network density first increased and then decreased,but overall remained at a relatively low level.Network hierarchy showed a fluctuating declining trend,indicating a transition from a hierarchical structure to a flatter one.Network efficiency first increased and then gradually decreased,while network stability improved.3)The degree centrality,closeness centrality,and betweenness centrality of Guangzhou,Shenzhen,Foshan,and Zhuhai remained at relatively high levels.4)The spatial correlation network of new-type urbanization helped improve territorial spatial utilization efficiency.However,this enhancement effect was more pronounced in the Pearl River Delta region,plain areas,and in the dimension of urban spatial utilization efficiency.[Conclusion]It is necessary to internalize network-based thinking to guide the transformation of new-type urbanization and to encourage cities to formulate differentiated development strategies based on their own resource endowments and functional positions within the spatial correlation network of new-type urbanization,thereby strengthening the role of the network in promoting territorial space efficient utilization.
[Objective]This study investigates the response characteristics of water storage at gully heads to rainfall in the black soil region of Northeast China,reveals the variation patterns of water storage at gully heads before and after rainfall,and establishes a quantitative prediction method for its changes before and after rainfall.[Methods]Four gully heads with similar developmental stages and scales in three study areas(Jiusan,Binxian and Jiutai)were selected as research objects.Differences in soil hydraulic parameters,decay coefficients of water storage,and variation patterns of water storage before and after rainfall were investigated through transient water release and imbibition method(TRIM),numerical fitting,and prediction model construction.[Results]Obvious hysteresis effects were observed in soil-water characteristic curves(SWCC)of soils at gully heads,with the intensity ranking as gully 1 ≈ gully 2＜gully 3＜gully 4.After rainfall,water storage decayed exponentially over time,showing rapid decline in the initial stage and slower decline in the later stage.The decay coefficient(Kd)of water storage decreased progressively with increasing soil depth.Model simulations showed that water storage changes at 85.7%of the monitoring sites were best predicted using 1 h maximum rainfall intensity(I1 h)as the rainfall input parameter,whereas 14.3%of the sites were better simulated using 2 h average maximum continuous rainfall intensity(I2 h)as input.Therefore,in predicting soil water storage changes,I1 h could be selected as the rainfall input parameter for sites with good infiltration performance,such as gully heads or severely eroded sites.However,I2 h should be selected as the rainfall input parameter for sites with poor infiltration performance or strong water redistribution.[Conclusion]The evolution of water storage at gully heads after rainfall in the black soil region of Northeast China can be effectively characterized using exponential decay patterns and short-duration rainfall indices.The constructed model can accurately and quantitatively predict short-duration water storage changes at gully heads at the event scale,which provides methodological support for prediction and early warning of gully erosion processes.
