Ecological Sustainable Development Research Articles

Evaluation of Tourism Ecological Security and Measurement of Regional Differences in China

ABSTRACT Expanding upon the Driver-Pressure-State-Impact-Response (DPSIR) model system, this work employs the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) approach, Kernel density estimation, Spatial autocorrelation, Dagum Gini coefficient, and geographic detectors to evaluate the ecological security level of China’s tourism industry from 2010 to 2020. Examining the tourism ecological security’s spatio-temporal evolution, geographical disparities, and driving variables is the goal of this study. One thing that stands out from the data is that (1) there is a clear increase trend in the time series of tourism ecological security (TES). (2) There is spatial variability and lack of landscape equilibrium when the general geographical distribution pattern in space gradually decreases from east to west. (3) According to the Dagum Gini coefficient, there is a decreasing geographical non-equilibrium of tourism ecological security, with the main cause of this non-equilibrium being the inter-regional disparity between the east and west. (4) The factors affecting the tourism ecological security are complex and diverse. These factors are closely related to the economy, environment and population of the city. The findings provide a reference for the sustainable development of regional tourism ecology.

Pattern and driver of Rosa roxburghii Tratt suitability and its effect on ecological services in karst desertification control areas

The eco-industry is an effective path to achieve ecological and economic sustainable development. However, the role played by Rosa roxburghii Tratt (R. roxburghii) industry in karst desertification control still needs to be determined. In this study, we predict the suitability probability and driving variables of R. roxburghii's distribution through a Maximum Entropy model, combining climate, population, vegetation, and soil data, and conducted a sample plot survey in a high-suitability area to explore the role of the R. roxburghii industry in ecological services by using adjacent non-R. roxburghii patches as comparisons. The results showed that South China Karst, with its simultaneous rain and heat climate characteristics, was the most suitable area for the industrialization of R. roxburghii in the world. In South China Karst, the area of no, low, medium, and high suitability zones for R. roxburghii was 4.2 × 105, 6.12 × 105, 4.64 × 105, and 4.42 × 105 km2, respectively, and population distribution was the dominant variable controlling its distribution. The net primary productivity, soil conservation, water conservation, mean species abundance, and aboveground biomass of the R. roxburghii monoculture plot in the high-suitability area were significantly lower than those of adjacent non-R. roxburghii lands and forest patches. Furthermore, the monoculture had higher trade-offs between provision, regulation, and support service. This study found that the monoculture of R. roxburghii industry, dominated by human activities, failed to improve ecological services and exacerbated the trade-offs between services. Therefore, future karst desertification control still needs to follow the agroforestry development path.

Rare Earth Elements Induce Drought Tolerance in Dicranopteris pedata from Ion-Adsorbed Rare Earth Mining Area in Southern China

The ion adsorption rare earth (IARE) mining areas in southern China frequently experience severe seasonal drought, posing significant challenges to plant growth. This study investigates the hypothesis that rare earth elements (REEs) present in these mining areas induce drought resistance in Dicranopteris pedata (D. pedata). An experiment was designed with three drought stress intensities (0%, 5%, and 10% PEG6000) and three levels of rare earth element (REE) addition (none, low, and high). After 72 h of drought stress, physiological indices and metabolomic profiles of D. pedata were examined. The results showed that under drought conditions, the REE additions increased the catalase and peroxidase activities of D. pedata by 99.04% and 81.25%, respectively, and the contents of proline, soluble proteins, and soluble sugars by 97.52%, 71.24%, and 61.81%, respectively. Metabolomic analysis revealed up-regulation of lipid and lipid-like molecules, as well as flavonoid metabolism, which contribute to improved drought resistance in D. pedata under stress. Furthermore, REE addition further up-regulated flavonoid and anthocyanin synthesis compared to drought stress alone, enhancing the plant’s resilience to drought. These findings suggest that D. pedata responds to drought stress by modulating enzyme activities, osmoregulatory substances, and metabolic pathways upon REE exposure. This study underscores the dual role of REEs in enhancing both the drought tolerance and enrichment capacity of D. pedata in IARE mining areas, which is crucial for sustaining plant growth amidst drought stress, and provides new ideas for the ecological restoration and sustainable development of IARE mining areas.

The dynamic patterns of critical ecological areas in the Yellow River Basin are driven primarily by climate factors but threatened by human activities

While the identification of critical ecological areas (CEAs) has been limited by the availability of resources, funds, and land space, these areas are central for maintaining the contributions from nature and ecosystem biodiversity. Thus, in this study, CEAs were systematically identified and classified via long-term ecosystem assessment with a multifunctionality–stability–integrity framework in the Yellow River Basin (YRB). The intensity and pathways of the driving factors of CEA dynamics were also determined by the geographical detector model (GDM) and the partial least squares structural equation model (PLS-SEM). The results revealed a gradual decrease in the proportion of CEAs in the upper and lower reaches from 2005 to 2020, in contrast with a significant increase in the middle reaches. The CEAs were distributed mainly in the Sanjiangyuan and Ziwuling regions and the Qingling, Qilian, Lvliang and Taihang Mountains. The areas with low, medium, and high levels of CEAs accounted for 12.48%, 17.73% and 12.54%, respectively, of the YRB. Moreover, climate factors, especially precipitation, were the foremost drivers influencing the dynamic patterns of CEAs. However, notably, the CEAs in the YRB experienced continuous degradation from 2005 to 2020 due to intensified human activities. Our results confirmed the important role of climate factors in determining the distribution of CEAs while underscoring the necessity of mitigating human disturbances to maintain ecosystem functions. These investigations of the dynamics and drivers of CEAs based on long-term multi-dimensional ecosystem assessments could provide useful insights for developing ecological conservation and sustainable development strategies.

Complex socio-economic solutions regarding the sustainable ecological development of the Ukraine regions

Complex socio-economic solutions regarding the sustainable ecological development of the Ukraine regions

Quantitative Assessment of Ecological Sustainability Development in Taiwan Coastal Zone Based on the Coastal Development Index

Quantitative assessment of coastal ecological sustainability development has received increasing interest in regional sustainable development research. It has a strategic value in guiding coastal zone management. We apply the Coastal Development Index (CDI) to quantify the ecological sustainability development in Taiwan coastal zone from 2000 to 2019. The results reveal a relatively high level of ecological sustainability with an overall inverted V-shaped trend in Taiwan coastal zone during this period. The coordination between environmental protection and economic growth in Taiwan coastal zone has experienced an uncoordinated → coordinated → uncoordinated process. Tracking the index of six sub-indicators shows some issues such as over-focusing on quantity rather than quality in coastal protection and facing a "green trap" in economic development. Moderate economic growth is crucial to realize the ecological sustainability development in Taiwan coastal zone. This study demonstrates the value of CDI in the quantitative assessment of ecological sustainable development with a detailed case study in Taiwan coastal zone. It also provides long-term historical data and information on Taiwan region, which may contribute to promoting coordinated development on both sides of the Taiwan Strait.

Ecosystem Services’ Response to Land Use Intensity: A Case Study of the Hilly and Gully Region in China’s Loess Plateau

The hilly and gully region of the Loess Plateau represents one of China’s most ecologically vulnerable landscapes, characterized by severe soil erosion, intensive land use, and pronounced disturbances to the structure and functionality of ecosystem services. Taking Zichang City as a case study, this research integrates grid-scale analysis with the InVEST-PLUS model and bivariate spatial autocorrelation techniques to examine the spatiotemporal dynamics and inter-relations of four critical ecosystem services—carbon storage, water yield, biodiversity, and soil retention—under varying land use intensity scenarios from 1990 to 2035. The findings indicate that (1) between 1990 and 2020, land use intensity in Zichang City steadily declined, exhibiting a spatial distribution pattern typified by central-area clustering and gradual peripheral transitions. (2) Across three development scenarios, the spatial distribution of the four ecosystem services aligned with the patterns observed in 2020, with central areas showing pronounced fluctuations, whereas peripheral regions experienced relatively minor changes. Specifically, from 1990 to 2020, the proportion of low-carbon storage areas increased by 2.89%, and high water yield areas expanded by 9.45%, while the shares of low habitat quality and low soil retention areas decreased by 5.59% and 6.25%, respectively. (3) A significant spatial autocorrelation was observed between land use intensity and the four ecosystem services, with widespread cold and hot spots reflecting dynamic spatial clustering patterns. These results offer valuable insights for optimizing land use strategies, improving ecosystem service performance, and advancing ecological conservation and sustainable development initiatives.

Changing characteristics, driving factors and future predictions of land use in the Weigan-Kuqa River Delta Oasis, China

The oasis serves as the central component of the arid ecosystem and plays a crucial role in supporting human activities. However, the ecological environment in the oasis region is fragile, and even a minor alteration in land use (LU) can significantly impact the stability of the ecosystem. Therefore, it is imperative to undertake comprehensive research on the spatio–temporal patterns of LU change in the oasis, reveal its driving factors, and predict future development. This is crucial for devising scientifically and logically sound land management strategies, upholding the equilibrium between humans and land in arid areas, and attaining sustainable development of the regional ecology and economy. This study focuses on the Weigan–Kuqa River Delta Oasis in China as the research area, analyzes the changes in LU in the oasis from 2010 to 2022 using various methods such as transition matrix, dynamic degree, intensity analysis, and center of gravity shift. The study also investigates the factors influencing these changes using the optimal parameters–based geographical detector (OPGD). Additionally, it predicts the future trends in LU development under four different scenarios using the mixed–cell cellular automata (MCCA), and illustrates distribution characteristics by combining Moran’s I index and hotspot analysis. The results suggest that: (1) Between 2010 and 2022, the LU in the oasis changed rapidly, with consistent increase in the amount of construction land, arable land, and garden land, while the amount of forest-grassland and unused land decreased overall. (2) Population density played a leading role in the changes, but soil type also had a significant impact. Over the course of time, the influence of roads and transportation has progressively increased. (3) Compared with 2022, the acreage of arable land, garden land, and construction land increases under the four future scenarios: natural development scenario (NDS), economic development scenario (EDS), cropland development scenario (CDS), and ecological protection scenario (EPS). However, the acreage of forest–grassland and unused land decrease. From a spatial perspective, large towns, the downstream of alluvial fans, and the central oasis are key areas where the distribution of hot spots and sub–hot spots of each LU type varies significantly among the four scenarios. The EPS provides a certain level of protection for forest-grassland areas and water bodies, making it the most appropriate development model for oases. These findings have the potential to offer valuable academic guidance for oasis land resource management and are crucial for achieving coordinated development at regional level.

Ecological Carrying Capacity and Driving Factors of the Source Region of the Yellow River in China over the Past 30 Years

The source region of the Yellow River (SRYR) serves as a crucial ecological barrier on the Qinghai–Tibet Plateau in China. In recent decades, the ecological condition of the SRYR has deteriorated, resulting in a state of ecological insecurity. This state of affairs endangers the region’s living environment, aggravates poverty, and seriously hinders the region’s sustainable ecological, social, and economic development. Ecosystems, landscape patterns, ecological carrying capacity (ECC), and drivers interact with each other in the region, shaping the regional ecological pattern’s past, present, and future. However, the specific mechanisms underlying these interactions have yet to be elucidated. Based on the land use type data of the SRYR in China for the last 30 years in seven periods (1990, 1995, 2000, 2005, 2010, 2015, and 2020), and combined with the ecological footprint method, we carried out a study of spatial and temporal changes at the county scale and the source region scale, used the landscape pattern index to describe the changes in ECC, and analyzed the main drivers that affect the ECC of the source region. The results indicate the following: (1) Over the past 30 years, the greatest changes in the area have occurred in grasslands and unused lands. Between 2005 and 2010, a significant conversion of unused lands to grasslands occurred in the SRYR, amounting to 7382.33 km2, mainly distributed in Maduo County and Maqin County. (2) The absolute ecological carrying capacity (AECC) of grasslands in the SRYR has shown an upward trend, while that of forests has declined. The ECC of the source region has generally increased, with higher ECC observed in Maqin County, Maduo County, and Xinghai County. (3) The spatial distribution of ECC in the SRYR has shown non-uniform changes, with an increasing trend observed across all county-level areas. The spatial heterogeneity of AECC is high, with minor overall spatial distribution changes. (4) There is a positive correlation between the ECC of the SRYR with SPLIT, PARA_MN, and COHESION (p < 0.05). The impact of landscape pattern indices on ECC ranked as COHESION > PARA_MN > SPLIT. (5) Principal component analysis indicates that the primary driving forces of the SRYR’s ECC are social factors, such as urban population (X5) and per capita GDP (X8), with natural factors being less significant than social factors. This research is crucial for maintaining ECC in the SRYR, protecting and restoring the ecological environment, and ensuring the sustainable development of the economy and society.

Identifying the Interactive Coercive Relationships Between Urbanization and Eco-Environmental Quality in the Yangtze and Yellow River Basins, China

Urbanization, as an important engine of modernization, plays an important role in promoting regional economy and improving living standards. Nevertheless, unchecked urban expansion over recent decades has strained natural resources and the environment, leading to crises, especially in densely populated urban areas that act as ecological barriers within river basins. The investigation of the interactive coercive relationship between the urbanization level (UL) and eco-environmental quality (EEQ) can facilitate the identification of sustainable pathways towards regional sustainability. Therefore, this study employed a set of multidisciplinary approaches, integrating simple linear regression, bivariate spatial autocorrelation, and coupling coordination degree (CCD) models, alongside multi-source remote sensing data to analyze the interactive coercive relationship between UL and EEQ in the Yangtze and Yellow River basins (YYRBs) in China. Key findings included a 6.97% improvement in EEQ in the Yellow River basin (YLRB) from 2001 to 2020, with higher values in the southeastern and southwestern regions and lower values in the central region, while the Yangtze River basin (YTRB) saw only a 1.28% increase, characterized by a lower EEQ in the west and higher levels in the middle and east, although the Yangtze River Delta showed a decline and significant variation among tributaries. UL rose steadily in both basins, especially in the middle reaches of the YLRB. Spatial autocorrelation analysis revealed a positive correlation between UL and EEQ in the YLRB, whereas a negative correlation was found in the YTRB. The CCD between UL and EEQ in the YYRBs improved, particularly in the middle and lower reaches, indicating the need for integrated urban development strategies that consider regional ecological capacities. These findings provided a scientific basis for ecological protection and sustainable urban development at a large river basin scale.

Revealing the synergistic spatial effects in soil heavy metal pollution with explainable machine learning models

The identification of factors that affect changes in the heavy metal content of soil is the basis for reducing or preventing soil heavy metal pollution. In this research, 16 environmental factors were selected, and the influences of soil heavy metal spatial distribution factors and the synergy amongst space factors were evaluated using a geographic detector (GD) and the extreme gradient boosting (XGBoost)-Shapley additive explanations (SHAP) model. Three heavy metal elements, namely, Cd, Cu and Pb, in the study region were examined. The following results were obtained. (1) XGBoost demonstrated high accuracy in predicting the spatial distributions of soil heavy metals, with each heavy metal having an R2 value of over 0.6. (2) Geological type map (Geomap) and enterprise density considerably affected the concentrations of Cd, Cu and Pb in soil in the GD and XGBoost-SHAP models. In addition, cross-detection revealed strong explanatory power when natural and human factors were combined. (3) Under the same geological background, the different trends of gross domestic product effects on heavy metals indicated that pollution control measures were effective in economically developed areas, and the economy and the environment could be balanced. Meanwhile, the interaction between the normalised difference vegetation index and enterprise density showed that vegetation could alleviate heavy metal pollution in the region. This study supports strategic decision-making, serving as a reference for the global management of soil heavy metal contamination, sustainable ecological development and assurance of people’s health and well-being.

Unveiling benefits: A framework for analyzing small hydropower refurbishment activities

Small hydropower is a crucial renewable energy source in China and plays a significant role in achieving social, economic, and ecological sustainable development goals. However, rapid Small hydropower development has led to various issues, resulting in closure or dismantling of many Small hydropower plants. To maximize the positive impact of Small hydropowers, green transformation and Small hydropower plant upgrades are urgently required. Hence, Small hydropower refurbishment activities are performed to enhance overall benefits. Therefore, this study integrated grounded theory, a qualitative research method, with a comprehensive decision-making trial and evaluation laboratory-fuzzy analytic hierarchy process evaluation model. This formed a new framework to analyse refurbishment activities and was applied in Tangban and Maoyandong plants. Small hydropower refurbishment activity benefits were categorized as internal (direct economic and indirect production benefits) and external (social and ecological benefits), with interconnections and trade-offs. The most critical factors influencing benefits were internal factors, whereas social benefits had a greater influence on external factors. The refurbishment activities at Tangban and Maoyandong were rated high and moderate, respectively, owing to differences in corporate nature, location, and primary business focus. This study not only provides a theoretical model for China’s Small hydropower to achieve the United Nations Sustainable Development Goals under the premise of sustainable operations, but also offers a new global framework for evaluation and decision-making in Small hydropower plants.

Feasibility Study on the Construction of Underground Reservoirs in Coal Goaf—A Case Study from Buertai Coal Mine, China

The construction of underground reservoirs in coal goaf is a new technology aimed to realize the sustainable development of coal mining-water storage-surface ecology in arid areas of northwest China. The key to the feasibility of this technology is that underground coal mining cannot affect the near-surface aquifer, and the amount of water entering the underground reservoir must meet the needs of the coal mine. Taking Buertai Coal Mine, one of the largest underground coal mines in the world, as an example, this article used similar simulation, numerical simulation and in-situ test methods to study the height of the water-conducting fracture zone of overlying strata and water inflow of underground reservoirs. The results show that, under the repeated mining of the 22- and 42-coal seams, the maximum height of the water-conducting fracture zone is 178 m, and the distance between the near-surface aquifer and the 42 coal is about 240 m, so the mining has little effect on the near-surface aquifer. During the mining period of the 22-coal seam, the groundwater of the Zhidan and Zhiluo Formations was mainly discharged vertically, while the groundwater of the Yanan Formation was mainly a horizontal flow during the period of the 42-coal mining. In this way, the total water inflow of Buertai Coal Mine reaches 500 m3/h, which not only meets the needs of the mine, but also, the rest of the water can irrigate about 98 hectares of farmland nearby. Underground reservoirs in coal goaf could achieve sustainable development of coal mining, groundwater storage and surface ecology in semi-arid areas.

The Assessment of the Spatiotemporal Characteristics of Net Water Erosion and Its Driving Factors in the Yellow River Basin

The Yellow River Basin (YRB) is an important grain production base, and exploring the spatiotemporal heterogeneity and driving factors of soil erosion in the YRB is of great significance to the ecological environment and sustainable agricultural development. In this study, we employed the Revised Universal Soil Loss Equation (RUSLE) in conjunction with Transport-Limited Sediment Delivery (TLSD) to explore a modified RUSLE-TLSD for use assessing net water erosion. This modification was performed using sediment data, and the explanatory power of driving factors was assessed utilizing an optimal parameters-based geographical detector (OPGD). The results demonstrated that the modified RUSLE-TLSD can accurately simulate the spatiotemporal distribution of net water erosion (NSE = 0.5766; R2 = 0.6708). From 2000 to 2020, the net water erosion modulus in the YRB ranged between 1.62 and 5.33 t/(ha·a). Specifically, the net water erosion modulus decreased in the YRB and the middle reaches of the YRB (MYRB), but it increased in the upper reaches of the YRB (UYRB). The erosion occurred mainly in the Loess Plateau region, while the deposition occurred mainly in the Hetao Plain and Guanzhong Plain. The Normalized Difference Vegetation Index (NDVI) and slope emerged as significant driving factors, and their interaction explained 31.36% of YRB net water erosion. In addition, the redistribution of precipitation by vegetation and the slope weakened the impact of precipitation on the spatial pattern of net water erosion. This study provides a reference, offering insights to aid in the development of soil erosion control strategies within the YRB.

Spatial–temporal effect of sea–land gradient on landscape pattern and ecological risk in the coastal zone: A case study of Dalian City

Abstract Coastal zones have intense human activity and are ecologically fragile. Assessing ecological risks in coastal zones is crucial to promoting ecological safety and sustainable development for coastal cities. However, the relationship between ecological risk assessment and distance from the coastline is indeterminate in current research. To solve this problem, this study constructs the sea–land gradient and reconstructs the landscape pattern index and landscape ecological risk index (ERI) considering the sea–land gradient paradigm. This study aims to analyze the spatial–temporal variation characteristics and effects of the sea–land gradient on landscape pattern and ecological risk in Dalian City from 2000 to 2015. The results show the following: (1) between 2000 and 2015, a significant effect of coastline on the coastal landscape pattern in Dalian is reducing landscape fragmentation. The extent of this influence gradually diminished along the sea–land gradient. The landscape aggregation of urban building sites near the sea was relatively high and gradually increased over the years; (2) in Dalian, the landscape ERI has decreased near the sea and increased near the inland year by year; (3) the dominant pattern of landscape ecological risk was characterized by a transition from high to low levels within the [0, 2.5] km zone, while a transition from low to high levels predominated within the [2.5, Max] km zone; and (4) the northern region in Dalian primarily goes from high to low risk in the buffer zone near the landside, whereas the southern area has this changing pattern in the buffer zone near the seaside.

Analysis of Spatio-Temporal Relationship Between Ecosystem Services and Human Footprints Under Different Human Activity Gradients: A Case Study of Xiangjiang River Basin

Clarifying the relationship between human activities and the provision of ecosystem services has received significant interest in recent years because of a growing need for sustainable socio-ecological system development. Using multi-source remote sensing data, we assessed the spatial and temporal distribution of the human footprint index and five ecosystem services under four human activity gradients from 2010 to 2020 in the Xiangjiang River Basin. The five ecosystem services include water supply, soil conservation, food production, habitat quality, and carbon sequestration. The relationship between human footprint and ecosystem services was analyzed from quantitative and spatial perspectives. The results showed that over the past 10 years, water supply and habitat quality decreased by 4.59% and 16.49%, respectively. The other three services increased, and the upstream area of the basin had a higher level of ecosystem services provision. The human footprint index increased by 28.83% over the 10 years and was characterized by point and patchy clustering in the middle and lower reaches. In terms of quantitative characteristics, the relationship between human footprint and ecosystem services was primarily negative. The ecosystem services were sensitive to the human footprint index within the 0−0.4 range. In terms of spatial characteristics, the relationship was dominated by trade-offs. The risky “high–low” trade-offs were mainly distributed in the middle and lower reaches. As the gradients of human activity increased, the maximum fluctuation in ESs was 43%, and the maximum fluctuation in human footprint was 28%, making their relationship more complex. Our results identified response thresholds of ecosystem services to human activities, providing a guide for ecological management and sustainable development of basins.

The Paths of Ecological Civilization Construction under the Concept of Sustainable Environmental Education

Ecological civilization is a new stage of human civilization development after industrial civilization, and it is an inevitable choice to cope with the global ecological crisis and achieve harmonious coexistence between humans and nature. With the deepening of China's ecological civilization construction, sustainable development education has gradually become an important means of cultivating public ecological awareness. This article first elaborates on the connotation of ecological civilization and its relationship with education, analyzes the current situation of ecological education in schools and society, and points out the existing problems. We must adhere to the integration of ecological civilization and sustainable development education, the integration of ecological civilization and educational governance, and develop education with the people as the center, building a path for the development of ecological civilization.

Spatial Characteristics and Driving Factors of Net Primary Productivity of Vegetation in the Upper and Middle Yellow River Basin

The Net Primary Productivity （NPP） of vegetation plays a crucial role in terrestrial ecosystems, and a detailed investigation into the annual average NPP and its driving factors is of significant importance for promoting regional ecological construction and sustainable development. This research utilized MOD17A3 annual average NPP data from 2000 to 2020 and employed methods such as trend analysis, Hurst index, random forest model, partial dependence model, geographic weighted regression, and partial least squares-structural equation model （PLS-SEM） to analyze the annual variation characteristics of NPP and its relationship with driving factors in the upper and middle reaches of the Yellow River. The results showed： ① During the period from 2000 to 2020, the annual average NPP in the upper and middle reaches of the Yellow River generally exhibited a year-on-year increasing trend, with 79.25% of the region showing a significant improvement in annual average NPP, while 0.25% of the region exhibited a severe degradation trend. ② The dominant influencing factors of the annual average NPP in the upper and middle reaches of the Yellow River included precipitation, NDVI, drought, and relative humidity. The suitable range for increasing annual average NPP was 400 mm to 650 mm for precipitation and 40% to 70% for relative humidity, and NDVI showed a significantly linear positive correlation with annual average NPP. Drought index was negatively correlated with annual average NPP. The annual average NPP tended to stabilize and did not decline further when the drought index exceeded the threshold of 8. ③ Extreme rainfall indirectly affected the variation in annual average NPP in the basin by influencing the vegetation growth condition. The impact degree of extreme rainfall indices on the annual average NPP in the basin was in the following order： R10>R95P>PRCPTOT>SDII>Rx5day>R99P. ④ The next steps in ecological construction in the upper and middle reaches of the Yellow River should focus on the arid and severely arid regions in the northern part of the Yellow River, adapting measures to local conditions and enhancing the regional ecological environment.

The influence of tree species on small scale spatial soil properties and microbial activities in a mixed bamboo and broad-leaved forest

Soil enzyme activity and microbial biomass play a critical role in myriad ecological processes. Bamboo and broad-leaved mixed forests have received widespread attention as important forestry models for ecological restoration and sustainable development; however, our understanding the influences of broad-leaved tree species in mixed bamboo forests on soil properties and microbial activity remains unclear. Here we sampled twenty-seven spatially interspersed stands of bamboo-Castanopsis chinensis Hance mixed forest (CCB), bamboo-Alniphyllum fortune (Hemsl.) Makino mixed forest (AFB), and bamboo-Choerospondias axillaris mixed forest (CAB), with different mixing ratios (0–10 %, 10–20 %, 20–40 % canopy proportions) in subtropical China, to examine the effects of tree species and mixed ratio on soil nutrients, microbial biomass, and enzyme activity. We found that the different forests exhibited variations in soil nutrient levels. CAB forests exhibit notably higher mean C, N, and P contents than AFB and CCB, particularly at a 10–20 % mixing ratio where SOC concentration reached 46.50 g/kg. CAB forests demonstrated significantly higher activities of invertase (mean 701.83U/g), urease (8393.44U/g), and catalase (501.73U/g) compared to AFB and CCB forests, with peak enzyme activities observed at a 10–20 % mixing ratio. Soil microbial biomass C and N were notably greater in CAB and CCB forests than in AFB forests. CAB forests also exhibited the highest soil microbial biomass P (mean 48.68 mg/kg), which rose consistently with an increased mixing ratio. Multiple factor analysis revealed that the enzyme activities were significantly correlated with the annual growth of fine roots in the forest and were positively correlated with resident C, total N, total P, C: N, and C: P. Overall, the results provide insights into the importance of tree species and crown size in bamboo and broadleaved tree mixed forest in soil features and the microbial activity while providing management guidance for the selection of mixed tree species for sustainable management of bamboo forest soil microenvironment.

Innovative Perspectives on Ecological Assessment in the Agro-Pastoral Ecotone of Inner Mongolia: An Integrated Evaluation and Forecast of Landscape and Ecological Risks and Drivers

The agro-pastoral ecotone of Inner Mongolia, one of China’s most ecologically vulnerable regions, requires careful evaluation and prediction of landscape ecological risks to improve its environment and support sustainable development. Our study built a model to assess the landscape ecological risks from 1990 to 2020 using land use data from Google Earth Engine. We examined the changes in landscape ecological risks and their driving factors through spatial autocorrelation analysis and geographic detectors. Future ecological risks from 2025 to 2040 were predicted using the multi-criteria evaluation-cellular automata-Markov model. Results revealed a declining trend in both disturbance and loss intensity across land use types, with the overall ecological risk index also decreasing. Higher risk areas were concentrated in the east and southwest, while lower risks were observed in the north and center. Temperature and precipitation are key natural factors, while the impact of Gross Domestic Product (GDP), a human factor, on ecological risk is increasing and surpassed natural influences in 2015 and 2020. In the future, the highest risk areas will remain in the southwest and northeast. This study provides detailed evidence and guidance for ecological safety and sustainable development in the agro-pastoral ecotone of Inner Mongolia.