Distribution of ecological restoration projects associated with land use and land cover change in China and their ecological impacts

Trends in habitat quality and habitat degradation in terrestrial protected areas

Protected areas are typically considered a cornerstone of conservation programs and play a fundamental role in protecting natural areas and biodiversity. Human-driven land-use and land-cover (LULC) changes lead to habitat loss and biodiversity loss inside protected areas, impairing their effectiveness. However, the global dynamics of habitat quality and habitat degradation in protected areas remain unclear. We used the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model based on global annual remotely sensed data to examine the spatial and temporal trends in habitat quality and degradation in global terrestrial protected areas. Habitat quality represented the ability of habitats to provide suitable conditions for the persistence of individuals and populations, and habitat degradation represented the impacts on habitats from human-driven LULC changes in the surrounding landscape. Based on a linear mixed-effects modeling method, we also explored the relationship between habitat degradation trends and protected area characteristics, biophysical factors, and socioeconomic factors. Habitat quality declined by 0.005 (0.6%) and habitat degradation increased by 0.002 (11%) from 1992 to 2020 globally, and similar trends occurred even in remote or restrictively managed protected areas. Habitat degradation was attributed primarily to nonirrigated cropland (62%) and urbanization (27%) in 2020. Increases in elevation, gross domestic production per capita, and human population density and decreases in agricultural suitability were associated with accelerated habitat degradation. Our results suggest that human-induced LULC changes have expanded from already-exploited areas into relatively undisturbed areas, and that in wealthy countries in particular, degradation is related to rapid urbanization and increasing demand for agricultural products.

Ecosystem services dynamics and their influencing factors: Synergies/tradeoffs interactions and implications, the case of upper Blue Nile basin, Ethiopia

Understanding the relationships among ecosystem services (ESs) and their interactions with influencing factors is essential for spatially targeted ecosystem governance. However, classifying the spatial distribution of these diverse interactions still needs improvement. Furthermore, existing studies have insufficiently addressed the specific impacts of bidirectional land cover transitions on ESs. Taking the upper Blue Nile basin as a study area, we estimated the spatiotemporal distribution of annual water yield (AWY), carbon storage (CS), habitat quality (HQ), and soil retention (SR) from 2000 to 2020, using InVEST models and associated formulas. Changes in ESs per inward-outward land cover transition were quantified based on the Cross-Tabulation Matrix. An improved pairwise method was employed to assess the spatially diverse interactions between ESs pairs and their relationship with influencing factors. The statistical significance of influencing factors was evaluated using partial least square regression. The findings indicated that high HQ values were prevalent in the west, while they were in the east for SR. The central and southern areas experienced higher CS and AWY values. During the study period, variations were observed in the mean values of SR (ranging from 22.89 to 23.88 × 102 t/ha/y), AWY (32.13-42.2 × 102 mm/ha/y), CS (90.5-102.9 × 103gC/ha/y) and HQ (0.62-0.64). Synergies were predominant in AWY-CS, AWY-SR, and CS-SR pairs. HQ revealed more of a no-effect and tradeoff relationship with other ESs. The interactions between ESs and influencing factors were dominated by synergies, followed by tradeoffs and no-effect. The influence of landscape structure (gyrate and landscape shape index) and land surface temperature on all ESs and precipitation on AWY and SR was significant (1.049 ≤ Variable Importance in the Projection ≤ 1.371). Overall, the spatiotemporal dynamics of key ESs and the modeling of their drivers are essential policy information for taking spatially explicit conservation measures. This study will also serve as a valuable methodological reference for future research.

Linking the assessment of ecological engineering construction with zoning management in the typical agro-pastoral area of China: A perspective from quantity, quality and function

Combatting land damage has become a global priority, and China has adopted a series of ecological engineering measures, especially in the agro-pastoral area with fragile ecological environment. The effectiveness of ecological engineering construction (EEC), from a comprehensive recognition encompassing its quality, quantity, and function, has remained largely unknown. To this end, Zhangbei County, a typical agro-pastoral ecotone of northern China, was chosen as our focal area. After summarizing the timelines, aims and results of the EEC during various periods in Zhangbei, the linear spectral mixture analysis was employed to process Landsat 5 TM images in 2000 and 2010, as well as Landsat 8 OLI images in 2020. Then, a comprehensive evaluation framework of EEC was established from the perspective of "quantity-quality-function", and the ecological effectiveness of EEC was evaluated from 2000 to 2020 in Zhangbei. Results revealed that EEC played a critical role in enhancing quantity, quality and function, in spite of that, there were still numerous regions showing varying degrees of degradation in terms of these aspects. Then, by extending the three-dimensional cube as the theoretical basis for the zoning management of EEC, we merged four zones according to the space matching relationship among quantity, quality and function of EEC, namely, Ecological conservation area, Ecological improvement area, Ecological restoration area and Ecological remodeling zone. More targeted ecological measures were required for specific matching relationship among quantity, quality and function of EEC. This study is expected to present an empirical case for assessing the ecological effectiveness of EEC in areas or countries with similar restoration demand and support regional management.

Multi-objective ecological restoration priority in China: Cost-benefit optimization in different ecological performance regimes based on planetary boundaries

In the context of the "United Nations Decade on Ecosystem Restoration", optimizing spatiotemporal arrangements for ecological restoration is an important approach to enhancing overall socioecological benefits for sustainable development. However, against the background of ecological degradation caused by the human use of most natural resources at levels that have approached or exceeded the safe and sustainable boundaries of ecosystems, it is key to explain how to optimize ecological restoration by classified management and optimal total benefits. In response to these issues, we combined spatial heterogeneity and temporal dynamics at the national scale in China to construct five ecological performance regimes defined by indicators that use planetary boundaries and ecological pressures which served as the basis for prioritizing ecological restoration areas and implementing zoning control. By integrating habitat conservation, biodiversity, water supply, and restoration cost constraints, seven ecological restoration scenarios were simulated to optimize the spatial layout of ecological restoration projects (ERPs). The results indicated that the provinces with unsustainable freshwater use, climate change, and land use accounted for more than 25%, 66.7%, and 25%, respectively, of the total area. Only 30% of the provinces experienced a decrease in environmental pressure. Based on the ecological performance regimes, ERP sites spanning the past 20 years were identified, and more than 50% of the priority areas were clustered in regime areas with increased ecological stress. As the restoration area targets doubled (40%) from the baseline (20%), a multi-objective scenario presents a trade-off between expanded ERPs in areas with highly beneficial effects and minimal restoration costs. In conclusion, a reasonable classification and management regime is the basis for targeted restoration. Coordinating multiple objectives and costs in ecological restoration is the key to maximizing socio-ecological benefits. Our study offered new perspectives on systematic and sustainable planning for ecological restoration.

Investigation of the spatial effects on PM2.5 in relation to land use and ecological restoration in urban agglomerations

Heavy pollution of particulate matter with an aerodynamic diameter of <2.5 μm (PM2.5) poses increasing threats to the living environment worldwide. Urban agglomerations often lead to regional rather than local air pollution problems. This study explored the underlying global and local spatial driving mechanisms of PM2.5 variations of the 195 county-level administrative units in the urban agglomeration in the middle reaches of the Yangtze River, China, in 2020, using the global spatial regression and geographically weighted regression methods. Results showed that (1) at the county level, there were spatial variations of PM2.5, fluctuating from 20.1263 μg/m3 to 44.8416 μg/m3. (2) The concentrations of PM2.5 presented a positive spatial autocorrelation with a remarkable direct spatial spillover effect. (3) Forestland, grassland, elevation and ecological restoration were negatively correlated with PM2.5 concentrations, the indirect spatial spillover effect of elevation was noticeable. (4) The indirect reduction effects of ecological restoration on PM2.5 concentrations were substantial in the Wuhan urban agglomeration. (5) The reduction effect of forestland, grassland, ecological restoration and elevation on PM2.5 showed a noticeable spatial heterogeneity. In the future, it is suggested regional variability and the spatial spillover effect of air pollution be taken into account in environmental governance. Simultaneously, utilization of the mitigation effect of ecological restoration on PM2.5 is anticipated for the concerted effort in air pollution governance.

Effectiveness and driving mechanism of ecological restoration efforts in China from 2009 to 2019

Over the past decades, China's rapid economic growth and industrialization have led to serious ecological concerns. To combat ecological degradation and promote ecosystem sustainability, China has made substantial investments in ecological restoration in recent decades. Nevertheless, a comprehensive analysis of the effectiveness and driving mechanisms of these efforts are still lacking. Therefore, this study aims to bridge this gap by employing national land-use survey data to evaluate the effectiveness and driving mechanisms of China's ecological restoration efforts during 2009-2019, with a specific focus on ecological land preservation, land use structure, and their contribution to ecosystem services. Additionally, the Geodetector model was used to detect potential influencing factors and driving mechanisms of these efforts. The results of this study revealed that: (1) Between 2009 and 2019, a total of 585,492.61 km2 of non-ecological land was successfully transformed into ecological land through various ecological restoration efforts. Most of these areas were previously unused or cultivated land. (2) Forest and grass plantations were the major ecological restoration efforts in China, accounting for 47.35% and 41.91% of the total restored ecological land, respectively. Grassland restoration clustered northwest of the Hu Line, while forest restoration concentrated mainly to the southeast. Water and wetlands restoration were mainly distributed around China's major rivers, such as the Yangtze River and Yellow River. (3) China's ecological restoration efforts contributed to a 2.53 trillion CNY yuan increase in ecosystem service value during 2009-2019, with over 65% of the increase attributed to ecosystem regulating services. (4) China's ecological restoration efforts were mainly influenced by anthropogenic factors, such as population, land use, and urbanization, while the non-linearly enhanced interaction between natural and other factors also deserves attention. China should balance urban expansion, agricultural development, and ecological preservation, aligning restoration with socioeconomic trends while establishing effective inter-regional ecological compensation mechanisms.

The rising human footprint in the Tibetan Plateau threatens the effectiveness of ecological restoration on vegetation growth

Ecological restoration projects in the Tibetan Plateau aimed to reverse ecosystem degradation and safeguard the fragile alpine ecological environment. However, it is still being determined if the vegetation restoration is successful on a large scale or reaches the expected magnitude, restricting our ability to adapt practices to maximise the benefit. With multiple vegetation indices (VIs: NDVI, LAI, and GPP) from satellite observations and random forest machine-learning models, we performed an attribution study on vegetation growth trends caused by climate change and human activities. Then, we further explored the relationship between vegetation growth and ecological projects and human footprint without the influence of climate. The results showed that climatic change was a relatively strong driver of vegetation growth. The positive contributions of ecological restoration occurred only in half of the plateau due to the increased human footprint. Vegetation enhancement resulting from ecological restoration occurred in 13.1%-23.1% of the plateau. Among these values, ecological restoration counteracted the negative climate effects in 4.7%-8.3% of the plateau (about half of the negative climate effect area). In forest and grassland protection areas, the ecological restoration was more successful. The study provides a better understanding of the role of ecological projects in vegetation restoration and potential threats to its effectiveness. This is essential to improve future restoration projects.

Sustainable governance of drinking water conservation areas based on adaptive thresholds

Drinking water quality is integral to the Sustainable Development Goals framework. At the present, China's drinking water conservation faces a number of challenges that are partially brought on by strict conservation measures that don't fully take into account human-land conflict and sustainable development. Taking the idea of adaptive governance, this study seeks to identify adaptive thresholds and adaptive solutions for compatible drinking water conservation and local development. Pressure and resistance to drinking water quality in its status, future potential, and adaptive thresholds were explored to identify sustainable governance for the Baimei Conservation Area, Fujian Province. Field research, local governance forums, and the Soil and Water Assessment Tool (SWAT) model were utilized to explore the drinking water quality pressure and resistance to drinking water quality. In order to uncover potential future changes in pressure and resistance, suitability analyses and multi-scenario simulations were used to examine the status quo, pressure, and resistance scenarios. Adaptive thresholds were then identified through SWAT modeling of each scenario to guarantee the drinking water quality is greater than Class II in the Core Conservation Area and Class Ⅲ in 2nd-grade Conservation Area, respectively. The research finds that construction land development and farming are the key pressures on drinking water quality, and forests and wetlands are the primary resistances. The expansion of construction lands and the increased wetlands was centered on potential future scenarios because farming has no room for growth and forests are already heavily covered. The adaptive threshold of construction land expansion is identified to be 10% without new wetlands but can be 20% by adding 10% wetlands in subbasins, 5, 8, and 9. This study confirms the potential of adaptive sustainability for drinking water conservation areas. A similar analysis procedure can also be adapted to enhance adaptive governance for the sustainability of other conservation areas nationally and globally.

Examining inequities in species loss due to land use in China from an interregional trade perspective

The escalating impact of land use pressures indicates we've exceeded the proposed safe planetary boundary. Economic shifts and increased trade drive China's demand for agricultural and forestry products, land-use changes, and subsequent biodiversity damage often occur far from where they are consumed. Given many species in China are endemic or endangered, neglecting these interconnected economic trends threatens its biodiversity conservation targets. Here, we first quantify species loss due to six land use types embodied in the life cycle at the Chinese sub-national level. Then, a Chinese high-resolution multi-regional input-output (MRIO) model was used to link threatened species to key industrial sectors in the supply chain, tracking the spatiotemporal patterns of land use species loss embodied in Chinese trade from 2007 to 2017. Our results reveal a 6% increase in aggregated species loss in China during the study period. This subtle change in species loss footprints in recent years is partially due to increases in consumption levels being offset by reductions in species loss intensity, though drivers vary by region. Notably, the Northwest and Southwest, known for their high species richness, suffer the greatest inequalities in species loss. The domestic species loss transfer most apparent in the outsourcing from the Eastern Coast to the Southwest. The Southwest registered the highest territory-based species loss, particularly for amphibians, while the highest impacts in the supply chain are associated with Forestry, logging, and related activities. Our analysis underscores the need for enhanced provincial dialogue to systematically value and monitor biodiversity, a key natural capital, and encourage its conservation. Our study effectively monitors the consumption-based species losses across China, which can further improve knowledge and dialogue on ecological challenges associated with trade.

The contributions of climate and land use/cover changes to water yield services considering geographic scale

Background

Water yield services are critical for maintaining ecological sustainability and regional economies. Climate change and land use/cover change (LUCC) significantly affect regional water yield, but the spatiotemporal variability of water yield services has been overlooked in previous studies. This study aims to explore the relative contributions of climate and land use/cover changes to water yield services at both grid and subwatershed scales.

Methods

This study employed the InVEST model to calculate the water yield in the study area and employed a multi-scenario simulation approach to investigate the impacts of climate change and LUCC on water yield at both grid and subwatershed scales. Furthermore, the contributions of these two types of changes to water yield were quantified.

Results

Firstly, upstream areas experience significantly lower annual average precipitation, temperature, and potential evapotranspiration than downstream areas, with worsening drought severity. Secondly, urbanization led to significant LUCC, with decreases in farmland and grassland and increases in forest, water, building land, and unused land. Thirdly, the spatial heterogeneity of water yield services remains consistent across different scales, but more pronounced spatial clustering is observed at the subwatershed scale. Fourthly, climate change is the primary factor affecting regional water yield services, surpassing the influence of LUCC. Lastly, LUCC significantly impacts water cycling in watersheds, with vegetation coverage being a critical factor affecting water yield.

Conclusion

These findings highlight the need to consider the complex relationships between climate change, LUCC, and water yield services at multiple scales in water resource management.

Planning a water-constrained ecological restoration pattern to enhance sustainable landscape management in drylands

Ecological restoration is an important approach to improving landscape sustainability. However, ecological restoration in drylands is strongly limited by water resources. Therefore, a technical route for ecological restoration in drylands that creates sustainable landscapes based on those water constraints is needed. In this study, we develop a spatially explicit framework named "Constraint-Pattern-Benefit" to plan ecological restoration patterns in Inner Mongolia, China. Based on a prediction of the ecosystem service (ES) increase under limited evapotranspiration as a water constraint, we constructed 5 landscape sustainability-related strategies with 100 ecological restoration scenarios, which considered fragmentation of restoration locations, distance to city, water consumption, and the allocation scale to determine the spatial arrangement of ecological restoration. Results show that the ES increase potential of ecological restoration under water constraints is distributed in the center of Inner Mongolia. The multi-objective scenario simultaneously achieves 59.1% water yield, 74.2% soil conservation, 57.2% sand fixation, and 52.8% carbon sequestration with 50% restored landscape. Considering the indicators of fragmentation, water consumption, and distance to city decreases the restored landscape fragmentation from 0.44 to 0.26, improves the restoration efficiency by 14.41%, and increases the beneficiary population by 35.5%, respectively. Small-scale allocation can further increase the ES realization efficiency, which is on average 4.8% higher at the city scale than at the provincial scale. Moreover, this approach focuses on the sustainable effect of the spatial arrangement on dryland landscapes at different scales, which provides methodological support for improving the sustainability of drylands.

Simulation of future land use/cover change (LUCC) in typical watersheds of arid regions under multiple scenarios

The rapid development of the social economy has promoted a continuous increase in the intensity and scale of land use by humans, which has seriously affected the sustainable development of the region. It is important to understand the land use/cover change (LUCC) in the arid region and its future development trends and to make reasonable planning recommendations for the sustainable development of the ecological environment. This study validates the patch-generating land use simulation (PLUS) model in a typical arid region, the Shiyang River Basin (SRB), and analyzes the applicability of the model in arid regions. On this basis, the PLUS model is combined with the scenario analysis method to design four scenarios including no policy intervention, farmland protection, ecological protection and sustainable development to analyze the dynamic changes in past and future land use in the SRB and to make corresponding planning recommendations for the development of each type of land use in the arid region. The results showed that the PLUS model had a better simulation effect in the SRB (its overall accuracy reached 0.97). Coupled models obtain better simulation results than quantitative and spatial models by comparing the mainstream models, with PLUS model that combines CA model and patch generation strategy showing better simulation results in the same category. From 1987 to 2017, the spatial centroid of each LUCC in the SRB moved to varying degrees due to a continuous increase in human activities. The spatial centroid of water bodies had the most obvious change, with a moving speed of 1.49 km/a, while the moving speed of built-up land increased year by year. The spatial centroid of farmland, built-up land and unused land all shifted toward the middle and lower plains, which is a further indication of increased human activity. Due to different government policies, the development trend of land use was also different under different scenarios. However, the four scenarios all showed that the area of built-up land will be increasing exponentially from 2017 to 2037, which would seriously affect the surrounding ecological land and have a negative impact on the local agro-ecological environment. Therefore, we proposed the following planning recommendations: (1) Land leveling work should be carried out on scattered farmland located at high altitudes and with slopes over 25°. Additionally, the land use of low-altitude areas should strictly adhere to basic farmland, increase the diversification of cropping patterns and improve the efficiency of agricultural water. (2) The relationship between ecology, farmland and cities should be reasonably coordinated and the existing idle built-up land should be efficiently used. (3) Forestland and grassland resources should be strictly protected and the ecological redline should be strictly observed. This study can provide new ideas for LUCC modeling and prediction in other parts of the world and provide a strong basis for ecological management and sustainable development in arid areas.

Analysis of the implementation effects of ecological restoration projects based on carbon storage and eco-environmental quality: A case study of the Yellow River Delta, China

As an important means to address global climate change and land-use/land-cover (LULC) change, ecological restoration projects (ERPs) have a large effect on carbon storage functions and eco-environmental quality. However, the various ERPs carried out in the Yellow River Delta region have important implications for ecological security strategies in China. Therefore, based on land-use data and remote sensing image data, with the help of ArcGIS and Google Earth Engine (GEE) platforms, this study uses the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model, an improved remote sensing ecological index (RSEI) model and other methods to deeply examine the evolutionary trends of eco-environmental quality and carbon storage during the implementation of ERPs in the Yellow River Delta and selects key implementation areas for in-depth analysis to determine the implementation effects of ERPs. Our findings suggested that the RSEI and carbon storage levels in the study area had opposite evolutionary trends from 2001 to 2020. Among them, the RSEI showed a fluctuating upwards trend (0.4461 (2001) and 0.5185 (2020)), while the total carbon stock showed a fluctuating downwards trend (30.67 Tg (2001) and 26.40 Tg (2020)). However, from 2015 to 2020, the RSEI and carbon storage were at a relatively stable level, which indirectly indicated that the ERPs carried out during the period from 2015 to 2020 had achieved a good comprehensive implementation effect. In addition, the areas with better improvement effects from 2015 to 2020 were primarily located in the mouth of the Yellow River Delta (Areas C and D), and their RSEI and the total carbon stock showed a certain upwards trend. This research can promote the formulation of the management strategy of ERPs in the Yellow River Delta, which is of tremendous importance to the ecological environmental preservation and high-quality development of the Yellow River Basin.

Limited co-benefits of protected areas in southwest China under current climate change and human modification

An ambitious new Post-2020 Global Biodiversity Framework "Kunming-Montreal Global Biodiversity Framework" has been developed. However, the combined effects of climate change and human modification can undermine the potential benefits of the global post-2020 conservation efforts. The co-benefits of stabilizing the climate, conserving biodiversity, and maintaining intact wilderness areas may help to persuade the general public of the need to quickly expand existing protected areas (PAs). To maximize the co-benefits after 2020, the careful optimization of existing (PAs) network and scientific identification of conservation targets are both essential. Here, we mapped hotspots of biodiversity, climate vulnerability, and wilderness in Southwest China (SWC). By analyzing the representativeness and gaps of the existing PAs network in SWC, we devised post-2020 conservation targets and highlighted their implications for decision-makers. Our results showed that the incongruence between hotspots of different species exists, indicating that habitats suitable for one taxon may not fully harbor other taxa. According to our assessment, the five jurisdictions of SWC have warmed on average by 0.4°C-1.1 °C over the past 60 years alone. In particular, biodiversity hotspots in SWC are undergoing stark climatic changes. We uncovered prominent conservation gaps in SWC's network of PAs, especially in terms of climate vulnerability and biodiversity. Due to their insufficient number and unreasonable spatial distribution, the PAs network in SWC may be not capable of meeting its biodiversity, climate vulnerability, and wilderness conservation objectives. To rectify this, we proposed a 3-step mission: milestone 2025, milestone 2030, and goal 2050, which aims to protect 23%, 28%, and 60% of the terrestrial area in SWC, respectively. Taken together, our study derived conservation priority areas with relatively clear spatial boundaries and importance levels, thus providing detailed, timely information for decision-makers to expand the PAs network and implement conservation measures varying in strictness in post-2020 conservation practice.

Environmental laws and ecological restoration projects enhancing ecosystem services in China: A meta-analysis

In recent decades, China has implemented ecological restoration projects (ERPs) to improve biodiversity and ecosystem services (ESs), accordingly, a series of environmental laws were issued to guide ecological restoration. However, quantitative evaluation of the effectiveness of ERPs remains ambiguous. To respond to the UN Decade on Ecosystem Restoration (UNDER), we conducted a meta-analysis of 85 peer-reviewed publications and an interdisciplinary evaluation framework based on China's environmental protection and land administration laws (EPLALs) were established to assess the effectiveness of ERPs. We found that ERPs enhanced ESs by 15-58%. Specifically, ERPs implemented in industrial/mining, and wetland regions significantly increased regulating and cultural services, and in arid and semi-arid regions mainly enhance provisioning services (72.98%). Climate factors were found to be crucial for ecological restoration effectiveness (temperature: r = -0.582, significance <0.05; precipitation: r = 0.635, significance <0.05). China's environmental laws emphasized management and investment in ecological restoration. However, the disclosure, public participation and real-time monitoring of ecological conditions need to be improved urgently. We therefore developed ERP-related policy recommendations and global lessons to help improve the effectiveness of ecological restoration.

Spatial-Temporal Variations and Trade-Offs of Ecosystem Services in Anhui Province, China

Research on the spatiotemporal evolution and trade-offs of ecosystem services (ESs) is important for optimizing the ecological security barrier system and promoting coordinated socio-economic development. Natural factors, e.g., climate change, and human factors, e.g., unreasonable land use, have impacted and damaged ecosystem structure and function, leading to challenges with ES trade-offs and the spatial identification of priority protected areas. Here, the spatiotemporal evolution characteristics of five ESs (water yield, nitrogen export, soil retention, carbon storage, and habitat quality) in Anhui Province, China, from 2000-2020 were analyzed based on the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model. The trade-offs and spatial patterns among different ESs were explored using Pearson correlation and hotspot analyses; the dynamics of natural growth, cultivated land protection, and ecological protection scenarios for ESs in 2030 were simulated and analyzed by coupling InVEST with the patch-generating land use simulation (PLUS) model. The results reveal the following. (1) From 2000-2020, increases in water yield and soil retention occurred, with concurrent declines in the other services; the total nitrogen high-value area was mainly concentrated in the plain, with the other services' high-value areas mainly concentrated in the Dabieshan and Southern Anhui Mountains, with each ES showing similar spatial distributions across years. (2) The ESs were mainly synergistic, with trade-offs mainly between nitrogen export and other services. (3) Hotspot overlap between water yield and the other ESs was relatively low; no more than 6.53% of ecosystems per unit area provided five ESs simultaneously. (4) Other than water yield, the ecological protection scenario was more conducive to improving ecosystem functions. This study's results indicate inadequate synergy among ESs in Anhui Province; competition among land types must be further balanced in the future. This study provides a basic reference for implementing ecological projects and constructing ecological security patterns.

Habitat quality dynamics in China's first group of national parks in recent four decades: Evidence from land use and land cover changes

As the most biodiversity-rich part of the protected areas system, habitats within the pilot national parks have long been threatened by drastic human-induced land use and land cover changes. The growing concern about habitat loss has spurred China's national park project to shift from pilot to construction phase with the official establishment of China's first group of national parks (CFGNPs) in October 2021. But far too little attention has been paid to the synergistic work concerning the habitat quality (HQ) dynamics of all five national parks. Here, the InVEST model, combined with a satellite-derived land use and land cover product and a hot spot analysis (HSA) method, was used to investigate the HQ dynamics at the park- and pixel-scale within the CFGNPs. Our results demonstrate that the past ecological conservation practices within national parks have been unpromising, especially in Giant Panda National Park, Northeast China Tiger and Leopard National Park (NCTL), and Wuyi Mountain National Park (WYM), where HQ as a whole showed a significant decline. Furthermore, more than half of Hainan Tropical Rainforest National Park (87.2%), WYM (77.4%), and NCTL (52.9%) showed significant HQ degradation from 1980 to 2019. Besides, increasing trends in the area shares of HQ degraded pixels were observed in all five national parks from 1980-1999 to 2000-2019. The HSA implied that the hot spots of high HQ degradation rates tend to occur in areas closer to urban settlements or on the edge of national parks, where human activities are intensive. Despite these disappointing findings, we highlighted from the observed local successes and the HQ plateau that the construction of CFGNPs is expected to reverse the deteriorating HQ trends. Thus, we concluded our paper by proposing an HSA-based regulatory zoning scheme that includes five subzones to guide the future construction of China's national park system.

Ecological risk changes and their relationship with exposed surface fraction in the karst region of southern China from 1990 to 2020

Due to anthropogenic disturbances, the karst region in southern China is vulnerable to ecological problems such as soil erosion and surface exposure. However, limited studies on variations in large-scale ecological risk (ER) and their influencing factors, particularly the coupling/decoupling relationship with an exposed surface fraction (ESF), make ER regulations and ecological restoration challenging. The present study evaluates the ER of eight typical karst provinces in Southern China from 1990 to 2020 using the technique for order preference by similarity to an ideal solution (TOPSIS) model and ecosystem services (habitat quality, water yield, carbon storage, soil conservation, and food production), and extracts the contemporaneous ESF using Landsat satellite data in Google Earth Engine (GEE). The spatiotemporal change of ER and ESF are analyzed, and their coupling/decoupling relationship and driving mechanism are explored using coupling coordination degree (CCD) and multi-scale geographically weighted regression (MGWR) models. The results show that: (1) Over the past 30 years, the ER has increased until 2010 and subsequently declined, with an increasing mean value (0.463-0.503), except in Chongqing municipality. The ESF decreased significantly (the mean value dropped from 44.7% to 38.7%), except that in Sichuan province. (2) The average CCD between ER and ESF decreased with fluctuation of -0.017, with a decoupling relationship (58.18%). The coupling area is larger than the decoupling area in the Sichuan area, while other provinces are opposite. (3) The coupling/decoupling relationship in the study area is mainly driven by terrain (elevation, slope) and socio-economic (population density, per capita GDP) factors. More attention should be paid to the role of these factors in the continuous reduction and control of ESF and ER. This study can serve as a reference for similar studies in karst regions, such as risk assessment and surface monitoring, rocky desertification control, ecological engineering layout, and territorial planning.

Multi-Scenario Simulation Analysis of Land Use Impacts on Habitat Quality in Tianjin Based on the PLUS Model Coupled with the InVEST Model

Land use change is an important cause of habitat quality change. In order to reveal the impact of urban land use change on habitat quality, and to explore sustainable development planning, this paper uses the city of Tianjin, China, as a case study. Based on land use data from 2000, 2010, and 2020, the PLUS model was first used to predict land use in 2030 under three scenarios, and the InVEST model was then used to assess habitat quality from 2000 to 2030. This study showed that habitat quality was highly correlated with land use change. The rapid expansion of construction land was the main reason for the year-by-year decline in habitat quality. From 2000 to 2030, habitat quality in Tianjin declined year-by-year according to the average habitat quality values for 2030 for the three scenarios: the Ecological Protection Scenario (EPS) > Natural Development Scenario (NPS) > Economic Construction Scenario (ECS). In the EPS, habitat quality will deteriorate and improve. It would be ecologically beneficial to continue to work on the revegetation of the Jizhou area. In the ECS, habitat quality will decline sharply. In Tianjin, urbanization will continue to accelerate. This is a threat to the sustainable development of the city.

Defining Household Typologies Based on Cropland Use Behaviors for Rural Human-Environment Systems Simulation Research: A Case Study in Southwest China

The dynamics of rural human-environment systems in developing countries have increasingly been attracting attention. Agent-based modeling (ABM) is a valuable simulation tool for detecting complex feedback loops in rural human-environment systems with a ‘bottom-up’ approach. However, such models require the prerequisite analysis of household typology to simulate households’ decision-making process, where a gap exists between having accurate classification criteria and a simplified modeling framework. This study aimed to develop a household typology for two selected counties in southwest China based on multivariate analysis techniques and the classification tree method. Four categories of socioeconomic variables, including labor conditions, resource endowments, economic status, and social connections, were screened as possible factors impacting agriculture practice decisions. The results showed that household diversification in the study area was mainly determined by diversified livelihood strategies of off-farm work, livestock breeding, subsidy dependence, and traditional planting. Five distinct household types were identified: non-farm households, part-time households, livestock breed households, subsidized households, and traditional planting households. The household types were associated with specific cropland use behaviors, and their decision-making behaviors were verified with bounded rationality theory (where the maximization of profits is the primary goal). The quantitative classification criteria obtained in this study were clear and could be easily identified and used by ABMs. Our study provides a basis for further simulation of the complicated rural human-environment systems in southwest China.

Multi-Scenario Simulation and Prediction of Regional Habitat Quality Based on a System Dynamic and Patch-Generating Land-Use Simulation Coupling Model—A Case Study of Jilin Province

Effectively evaluating and predicting the change trend in regional habitat quality and its response to land-use change is of great significance for promoting regional high-quality and sustainable development. In this study, Jilin Province is taken as an example, and the SD–PLUS coupling model and the habitat quality module of the InVEST model are used to simulate the habitat quality of Jilin Province in 2030. In addition, the population and urbanization rates under the SSPs path are taken as the scenario framework, and the habitat quality changes from 1995 to 2030 are discussed. The results showed that the kappa coefficient of the simulation results was 0.93, and the FoM coefficient was 0.102. The simulation effect was good. The land-use simulation results under the four scenarios were quite different, and the change areas were mainly concentrated in the northwest, southeast, and central urban areas of Jilin Province. From 1995 to 2015, the habitat quality showed spatial distribution characteristics of “high in the southeast and low in the northwest”, and the habitat quality continued to deteriorate. By 2030, the ecological priority scenario (S3) is expected to have the maximum average value of habitat quality. Under this scenario, the scale of ecological land, such as forest, increases, and the scale of construction land is controlled. The minimum habitat quality appeared in the situation of rapid expansion (S2), and the increase in low-quality habitat areas was highly consistent with the expansion trend in urban construction land. In the coordinated development scenario, the growth rate of construction land reached 52.26%, but the average value of habitat quality decreased by only 0.0002, which basically found the balance point between economic development and ecological protection. S4 had a high reference value for the future development of Jilin Province.

Cross-Evaluation of Soil Moisture Based on the Triple Collocation Method and a Preliminary Application of Quality Control for Station Observations in China

Soil moisture (SM) measurements from ground stations are often after quality control (QC) in the operational system, but the QC flags may not be reliable in some cases when precipitation events or manual watering happen. This study applies the triple collocation (TC) method to conduct a cross-evaluation of SM data from ERA5 reanalysis estimates, ESA-CCI estimates, and ~2000 ground stations across the China domain. The results show that all datasets can capture the spatial pattern of SM in China. TC-based correlation coefficient (CC) and root mean square error (RMSE) show that the station data have worse performance in western and central China. For most stations, TC-based CC is between 0.6~0.9, and TC-based RMSE is between 0.01~0.06 m3/m3. In addition, TC-based metrics show good agreement with the CC between precipitation and SM, indicating that these metrics can reflect the quality of station data. We further selected typical stations (e.g., CC ≤ 0.2, RMSE ≥ 0.06 m3/m3) to check the quality of the QC procedure. The comparison shows that TC-based metrics can better represent the actual quality for these stations compared to raw QC flags. This study indicates that TC has the potential to detect problematic stations and could be a supplement to traditional QC of station observations.

Anti-erosion reclamation and its economic efficiency

One of the most acute problems of agriculture in some regions of the Russian Federation, including the Republic of Tatarstan at present is a progressive degradation of the soil cover. Every year the scale of water erosion increases, causing huge damage not only to agriculture but also to large and small rivers of the region. In this regard, there is a need to analyze the impact of soil erosion on the efficiency of agricultural production and the development of science-based anti-erosion measures to combat soil erosion in agriculture of the Republic of Tatarstan. The results of the carried out research testify that ecological efficiency of one anti-erosion construction in complex with soil protection measures protects on the average 120 ha of lands from further development of erosion processes, economically pays back by the results of two years of economic activity on the protected lands. The practical significance of the research results lies in the fact that they can not only contribute to the development of the agro-industrial complex and other sectors of the economy, provide an increase in soil fertility, a dynamic increase in agricultural production, reduction of retirement of agricultural land and the creation of new jobs. They also ensure the conservation and restoration of water resources.