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Abstract Climate change leads to permafrost thawing, accelerating carbon emissions increases, challenges the goal of climate change mitigation. However, it remains unknown whether implementing ecological restoration projects in Alpine areas can offset the adverse effects of permafrost thawing locally. Here we took the Qinghai‒Tibet Plateau as an example to explore this issue based on the improved Biome-BGCMuSo model. We found future climate change-induced permafrost thawing will decrease carbon sink. Projects’ carbon sink enhancement could fully counteract the permafrost thawing-induced carbon loss. Additionally, future warmer and wetter climates will enlarge the suitable area for restoration. If these areas are taken into account, carbon sink attributable to Projects will further increase. These results indicate that ERPs have the potential to combat future permafrost thawing-induced carbon loss, and their contribution will be further amplified by future climate change.

Wind erosion increases risks to soil productivity and food security, which have large implications for ecosystems and human well-being. However, the spatial patterns of how ecological restoration and climate change affect wind erosion remain poorly understood. Here, we combined scenario analysis with wind erosion assessment to evaluate the spatial associations of wind erosion with ecological restoration and climatic factors on the Tibetan Plateau. A structural equation model (SEM) was developed to determine the major driver of wind erosion. We identified an overall decrease of wind erosion modulus during 2001–2018, followed by increases of 7.2–19.4% under different climate change scenarios in 2030. Nearly two-thirds of the study area was characterized by wind erosion primarily driven by climate change, while ecological restoration accounted for the wind erosion in almost two-fifths of the study area. The SEM revealed a dominating role played by wind speed in affecting wind erosion directly and indirectly by modulating soil and vegetation conditions. Our study highlights the importance of embracing the spatial variations in the impacts of ecological restoration and climatic factors into the systematic planning of soil conservation and management. Results of this study could inform response strategies aiming to prevent and control wind erosion by identifying the location and extent of affected ecosystem services in the context of climate change.

Grasslands are important terrestrial ecosystems and key sources of primary productivity for livestock on Earth. It is very important to clarify the trend of the balance between grassland and livestock for sustainable development. Focusing on the unique alpine grassland ecosystem that is widely distributed in the Tibetan Plateau (TP), we assessed the grassland carrying capacity (GCC) and overgrazing in 2000, 2010 and 2020 considering grassland productivity, forage utilization of different grassland types, forage loss from diseases and pests and actual grazing intensity. Structural equation modelling was used to analyse the multifactor interactive driving mechanism of changes in GCC and overgrazing. The results showed that 1) From 2000 to 2020, although the total area of grassland decreased slightly, the amounts of edible forage, forage utilization, loss from diseases and pests, and GCC increased by 21.29%, 21.08%, 22.25% and 15.90%, respectively. 2) The overgrazing first intensified and then alleviated from 2000 to 2020 on the TP, but there was a serious grass-livestock imbalance (overgrazing ratio of 119% in 2020), with 80% of its counties being overgrazed in 2020. 3) From 2000 to 2020, climate change and ecological protection created synergistic effects on the grass-livestock balance on the TP. Climate warming and wetting directly raised grassland productivity, and indirectly benefited GCC by promoting grassland restoration and protection. Alleviation of overgrazing by ecological protection shifted from a direct effect to an indirect effect through enhancing the GCC. The contribution of grazing to overgrazing gradually declined as social and economic development relied less on nature over time. Our study quantitatively reveals the dynamic changes in GCC and overgrazing on the TP, and has implications for the sustainable utilization of grasslands in regions such as the TP, where ecosystems are important and fragile and vulnerable to the impact of climate change and human activities.

In agricultural landscapes, patches containing diverse species can serve as nodes, and species diffusion among these patches can serve as edges, forming metapopulation networks. However, the impact of landscape fragmentation on these networks and consequences for keystone crop species remain unclear. Here, we investigated thrips (pests) and lacewings (natural predators) in mango orchards and surrounding habitats across 15 landscapes. Using a machine learning neural network, we built metapopulation networks for thrips and lacewings based on the relationship between patch properties and species abundance. We evaluated these networks with metrics like clustering coefficient, strength, and path length. Furthermore, we analyzed the effects of landscape fragmentation, as indicated by edge density and landscape Shannon diversity, on network structures and the subsequent effect on species abundance using piecewise structural equation modeling. The results show that the neural network effectively constructed the metapopulation network, accurately predicting lacewing and thrips abundance in various patches with an accuracy rate exceeding 80%. Positive correlations were observed between edge density and network strength for both species. However, a positive relationship between landscape Shannon diversity and network path length was identified only for lacewings. Edge density had a greater impact on lacewings and thrips compared to landscape Shannon diversity, with a negative effect on lacewings and a positive effect on thrips. Edge density affected lacewing abundance both directly and indirectly through network strength. However, no network structure mediated the effect of landscape fragmentation on thrips abundance. Our conclusion highlights that the effects of landscape fragmentation on species are primarily driven by edge effects. These effects were clarified by the metapopulation network structure, which varied depending on the species. The findings provide new perspectives on metapopulation networks to unlock the landscape fragmentation effects.

Ecological restoration policies and their implementation are influenced by ecological and socioeconomic drivers. Top-down approach-based spatial planning, emphasizing hierarchical control within government structures, and without a comprehensive consideration of social–ecological interactions may result in implementation failure and low efficiency. Although many researchers have indicated the necessity to engage social–ecological interactions between stakeholders in effective planning processes, socioeconomic drivers of ecological restoration on a large scale are difficult to quantify because of data scarcity and knowledge limitations. Here, we established a new ecological restoration planning approach linking a social–ecological system framework to large-scale ecological restoration planning. The new spatial planning approach integrates bottom-up approaches targeting stakeholder interests and provides social considerations for stakeholder behavior analysis. Based on this approach, a meta-analysis is introduced to recognize key socioeconomic and social–ecological factors influencing large-scale ecological restoration implementation, and a stochastic model is constructed to analyze the impact of socioeconomic drivers on the behavior of authorities and participants on a large scale. We used the Yangtze River Basin-based Conversion of Cropland to Forest Program (CCFP), one of the largest payments for ecosystem service programs worldwide, to quantify the socioeconomic impacts of large-scale ecological restoration programs. Current CCFP planning without socioeconomic considerations failed to achieve large-scale program goals and showed low investment efficiency, with 19.71% of the implemented area reconverting to cropland after contract expiry. In contrast, spatial matching between planned and actual restoration increased from 61.55% to 81.86% when socioeconomic drivers were included. In addition, compared to that with the current CCFP implementation, the cost effectiveness of spatial planning with social considerations improved by 46.94%. Thus, spatial optimization planning that integrates both top-down and bottom-up approaches can result in more practical and effective ecological restoration than top-down approaches alone. Our new approach incorporates socioeconomic factors into large-scale ecological restoration planning with high practicality and efficiency.

Summary: The interactions between human and natural systems and their effects have unforeseen results, particularly in the management of water resources. Using water stress mitigation as an example, a water resources management effect index (WRMEI) was created to quantitatively evaluate the trends of water management effects. This revealed that the WRMEI was decreasing due to the impact of the water resources management process. The findings demonstrate that water resources management has unintended effects: there was a gap between the expectation of water stress to be mitigated and the actual results of water stress increasing. That is caused by human activities in water utilization: (1) increasing available water resources from water transfer was not utilized sparingly in the receiving cities—increased water transfers from external sources increase domestic water consumption per capita; (2) improving water efficiency has a positive effect on mitigating water stress, but the population growth decreased the efficiency. It was concluded that much greater attention needs to be paid to water conservation in residential and living use to counter these unintended water management effects.

When compounded by climate change, ecosystem degradation puts coastal communities at increased vulnerability to hazards. However, there have been few quantitative assessments of coastal vulnerability to multiple hazards that synthesize climate scenarios and ecological and demographic characteristics to inform adaptive strategies. This study presents such a framework for assessing coastal vulnerability to sea level rise, storm waves and winds under present and future climate scenarios. As a case study, we applied it to Macao, one of the most densely populated and highly urbanized coastal area in the world. We found 19% of the coastline hosting 349,000 people – distributed primarily along the Macao Peninsula coast – are highly exposed to coastal hazards at present. Almost half of Macao's total coastline with about 121,000 people are protected by natural habitats. The proportion of highly-exposed coastline was estimated to double, and that of highly-threatened population was estimated to increase by 26.9–44.1%, by 2100. Our findings provide insights into the spatiotemporal heterogeneity of coastal vulnerability to multiple hazards and highlight the role played by habitats in shielding coastal communities. The results can inform prioritizing coastal areas for conservative and adaptive strategies, thereby minimizing deleterious development pressures and enhancing the resilience of coastal communities.

Ecological products and ecosystem services are essential for human survival and development. Gross Ecosystem Product (GEP) is a method to combine the value of ecosystem services and can reflect the status of ecosystem and ecological conservation and restoration performance. The conservation and restoration of desert ecosystems play an important role in expanding global cultivated land, ensuring food security, and improving human wellbeing. However, ecosystem services and the value of GEP in deserts have been neglected. Taking the Kubuqi Desert ecosystem as an example, this study evaluated the pattens, GEP value, and its change in the Kubuqi Desert ecosystem from 2000 to 2020. Our study found that 1) over the past 20 years, the areas of wetlands, forests, grasslands, and shrubs in the Kubuqi desert ecosystem had increased by 100.65%, 6.05%, 2.24%, and 2.03%, respectively, while that of desert had decreased by 10.62%; 2) the GEP of Kubuqi in 2020 was 55.48 billion CNY, among which its sandstorm prevention value was the highest (39.39%); 3) The value of ecosystem services in the Kubuqi desert ecosystem were all increased over the 20-year period and the largest increase came from sandstorm prevention (increased by 195.09%). This study emphasizes how GEP accounting can promote desert conservation and restoration, quantifies the contribution of desert ecosystems to human wellbeing, and provides future GEP accounting suggestions for desert ecosystems. This study can provide scientific information on the conservation and restoration of global desert ecosystems.

Abstract Air pollutant removal by urban vegetation is perceived to be a key ecosystem service for mitigating air pollution. However, the effectiveness of air phytoremediation in cities requires more synthesis to inform environmental management. A Bayesian meta-analysis approach was used to quantify the effectiveness of the removal of typical air pollutants—particle matter (PM), nitrogen oxide (NOx), sulfur dioxide (SO2) and ozone (O3)—by synthesizing global field measurement studies. The results revealed that urban vegetation can mitigate the growth of air pollutant concentrations, with reduction rates of 16.5~26.7% for PM, 13.9~36.2% for NOx, and 20.5~47.8% for SO2. However, they failed to significantly mitigate ground-level O3, corresponding to an increase of 5.1~25.9%. The variability in effect sizes was mainly influenced by the distance to nearest highway, ambient concentration, relative humidity, and green coverage. A questionnaire survey conducted in Shenzhen city (China) showed that most environmental managers supposed positive impacts of urban vegetation on all four air pollutants, which was at odds with our findings with respect to O3. This study can inform the lessening of discrepancies between scientific research and environmental managers’ perceptions on how to improve air phytoremediation for urban air pollution mitigation in China and elsewhere.

Ground-level ozone (O3) pollution has been a severe environmental and health problem for decades. The importance of biogenic volatile organic compounds (BVOCs) in the formation of tropospheric photochemistry O3 has been highlighted, especially in areas of rapid urbanization. We conducted simultaneous measurements of trace gases, including NO, NOX, O3, and BVOCs (i.e., isoprene and α-pinene), in the urban and rural forest areas of Beijing to determine the relationships between them. The results highlight the differences between the urban and rural forest areas of Beijing in terms of ambient air concentrations of BVOCs and O3, and the interrelationships between BVOCs, NOX, and ozone were quantified. Moreover, the isoprene concentration was found to be higher in the atmosphere of the urban site than of the rural site, which had higher α-pinene concentrations and higher O3 concentrations. The NOX concentration was higher at the urban site than at the rural site, and there was a significant exponential relationship between NOX and O3 at the urban site, indicating that the impact of NOx on O3 at the urban site was greater than that at the rural site. The O3 concentration increased with rising isoprene and α-pinene in both sites. In the case of substantially increased BVOC concentrations, declining NOX concentrations strongly promote the formation of O3. Consideration should be given to planting tree species with low-BVOC emissions, as they are crucial for mitigating O3 pollution in urban areas. Additionally, the relationships between BVOCs, NOX, and O3 should be considered in policymaking related to O3 control.

With further urbanization, household consumption firmly plays a key role in China’s national carbon emissions. However, current research concerning carbon issues has mainly focused on urban household consumption, and few studies have paid attention to herder households, leading to a research gap in the field of low-carbon shifting related to nomadic economies. In this study, we interviewed more than one-thousand herder households in the Sanjiangyuan region of the Qinghai–Tibet Plateau in China. The household carbon emissions and their influencing factors were investigated across the herder households of 15 counties. Our findings revealed the following: (1) There exist differences in the amounts of household carbon emissions and their compositions in the Sanjiangyuan region. From the perspective of spatial distribution, the emission hotspots are mainly concentrated in the eastern part of the Sanjiangyuan region. (2) At the prefecture level, average personal emissions were larger in the Hainan Prefecture (3.26 t ce/year), while they were approximately 1.36 times that of the Huangnan Prefecture (2.4 t ce/year), though with smaller personal emissions. The indirect carbon emissions of the four prefectures all occupied larger percentages of household carbon emissions that were mainly contributed by food consumption and housing. (3) Family type was the main diver influencing personal carbon emissions in the Huangnan Prefecture, Guoluo Prefecture, and Yushu Prefecture. The more people living in the household, the lower the per capita carbon emissions. However, the effect size of potential carbon reductions was weakened when the number of family members rose to over three. (4) We propose that grazing prohibitions and low-carbon dietary shifts would contribute to low-carbon herder livelihoods, especially for small-sized households that should be peer-to-peer targeted by regional government propaganda, which may help to strengthen the implementation of in-depth low-carbon promotions across the Sanjiangyuan region and even the overall Qinghai–Tibet Plateau.

The influence of freshwater ecosystems on terrestrial taxa in high-altitude regions with challenging access, such as the Tibetan Plateau, remains inadequately understood. This knowledge gap is particularly significant due to the fragility of these ecosystems, characterized by low primary productivity. Ungulates, in particular, may exhibit high sensitivity to even minor alterations in plant availability, potentially stemming from global climate change. Consequently, the investigation of these ecosystems may offer valuable insights into addressing future challenges posed by climate change. Here, to fill this knowledge gap, we explore the relationship between lakes and Tibetan antelopes in an even more vulnerable region, the Tibetan Plateau. We found that the Tibetan antelope population was higher in areas with larger lakes, and where the terrain near the lakes was flatter. At the same time, vegetation cover and plant diversity were higher near the lake compared to areas farther away from the lake. This phenomenon can be elucidated by the fact that lakes offer Tibetan antelopes a richer food supply and reduced predation risk. Our study provides new perspectives for researchers to explore the cross-ecosystem impacts of climate change.

Abstract Given the increasing attention to climate change and rising CO2 (CCRC) in the global carbon cycle, we remain unclear about how China's unprecedented land use/cover change (LUCC) in the carbon budget has been affected by CCRC in recent decades. Here, we combined remotely sensed land use/cover (LUC) datasets and the Biome‐BGCMuSo model to address this issue by setting different scenarios. We found that LUCC led the carbon sink to increase by approximately 104.24 ± 46.52 Tg C without considering CCRC during 1990–2020. Carbon sinks contributed by afforestation (374.97 ± 36.50 Tg C) and grassland planting (15.75 ± 9.11 Tg C) offset other LUC trajectories caused carbon loss (286.47 ± 32.18 Tg C, 87.33% owing to agricultural reclamation). LUCC contributed carbon sinks were amplified by ∼20% under CCRC at the national scale. This rate increased to 106.03% in northeast China but decreased to −26.68% in southern China. CCRC led carbon sink contributed by afforestation amplified by 85.11% in northeastern China but was only 26.35% in southern China. CCRC amplified carbon emissions due to agricultural reclamation by 103.20% in northeastern China and by 25.09% in southern China. Our results demonstrated that ecological restoration projects are efficient in enhancing carbon sinks and mitigating emissions. Divergent amplifying/reducing effect of CCRC across different geographic regions implied the sensitivity of different LUC trajectories to CCRC varied with different climate backgrounds. Land management strategies should be implemented with spatial heterogeneity to amplify afforestation and grassland planting contributed carbon sinks and decrease other LUC trajectories caused carbon loss under the global change environment.

Landscape structures affect pests, depending on compositional heterogeneity (the number and proportions of different habitats), configurational heterogeneity (spatial arrangement of habitats), and spatial scales. However, there is limited information on the relative effects of compositional and configurational heterogeneity on invasive pests and their associates (species that can benefit from invasive pests), and how they vary across spatial scales. In this study, we assayed the invasive pest Bactrocera dorsalis (Hendel) and its associated fly Drosophila melanogaster in 15 landscapes centered on mango orchards. We calculated landscape composition (forest percentage, mango percentage, and Shannon's diversity) and configuration (edge density) using two methods: spatial distance scales and combined scales. Spatial distance scales included buffer rings with radii of 0.5, 1.0, and 1.5 km, and combined scales referred to cutting or not cutting a smaller ring from larger ones. Our results shown that compositional heterogeneity positively affected B. dorsalis and D. melanogaster due to forest cover percentage, whereas configurational heterogeneity with high edge density negative effect on B. dorsalis. Forest cover had less of an effect on B. dorsalis than configurational heterogeneity, but the opposite effect was observed for D. melanogaster. Importantly, the direction and strength of forest cover and configurational heterogeneity to species did not vary with spatial distance scales or spatial combined scales. Thus, compositional and configurational heterogeneity exhibit differential effects on this invasive pest and its associator, and revealed that the relative effects of landscape structures are consistent across multiple scales. These results provide new insights into landscape effects on interconnected species using a diverse spatial-scale approach.

Soil erosion exerts a profound impact on the stocks of soil organic carbon (SOC), disrupting the carbon cycle and contributing to global warming. Through its role in mitigating soil erosion, the soil retention service of ecosystems holds the potential to stabilize and safeguard the SOC reservoir. This facet has yet to be comprehensively investigated. In this study, we quantified the preservation of SOC resulting from soil retention services in China, achieved by estimating both actual SOC erosion and potential SOC erosion using the Universal Soil Loss Equation (USLE). We find that (1) annually, SOC erosion in China amounted to 0.10 Pg C, primarily concentrated in croplands (47.8%), grasslands (21.2%), and barren lands (15.7%). Noteworthy hotspots emerged within the Soil and Water Conservation Divisions (SWCD) of key regions like the Tibetan Plateau (TP), the southwestern purple soil region (SW), and the karst region (KT). (2) The soil retention service curtailed the loss of a substantial 4.18 Pg C of SOC per year, predominantly attributed to forest ecosystems (66.1%). Hotspots of this preservation were clustered in the SWCD of the southern red soil region (SR), KT, and TP. These outcomes highlighted the critical role of soil retention services in preventing considerable carbon losses from terrestrial ecosystems. It significantly contributes to climate change mitigation and warrants recognition as an important nature-based solution in the pursuit of carbon neutrality. Forest ecosystems emerge as paramount in SOC preservation, which will be further improved with forest restoration. Beyond addressing soil erosion, future endeavors in soil and water conservation must equally address SOC erosion to comprehensively tackle carbon loss concerns.

Human activities are one of the main factors threatening the long-term survival of wild giant pandas. Long-term and large-scale human activities can be quickly assessed by night light remote sensing data, which has been more and more widely used. In this paper, we analyzed the spatial patterns of nighttime light intensity and their dynamic changes from 2000 to 2020 in the entire giant panda distribution area using long-term nighttime light remote sensing data, and evaluated the dynamic threats of nighttime light-represented human activities to giant panda populations by proximity of light source and its intensity. We also assessed the relationships between the nighttime light dynamics and the trends of habitat fragmentation. Results showed that the intensity and range of the nighttime light around panda habitat had increased significantly from 2000 to 2020. The nighttime light intensity inside the natural reserves is significantly lower than outside, and it becomes more obvious over time. The intensity and range of nighttime light inside the natural reserves first increased and then decreased during the two decades, indicating that the protection inside the natural reserves effectively reversed the rapid increase in human activities in the previous decade. From 2000 to 2020, nighttime light sources became closer to local panda populations. In particular, they approached the pandas in the first decade, and stayed away in the second decade. This is mainly reflected in the weakened threats of nighttime light-represented human activities on the core large populations of the Qinling, Minshan and Qionglai Mountains from 2010 to 2020, but the threats on the peripheral populations continued to strengthen, where nighttime light became not only closer but also more intensified. The increase in nighttime light intensity and range were also significantly positively correlated with the increase in habitat fragmentation, especially during 2000–2010. Our study reveals the dynamic changes of nighttime light-represented human activities’ threats to wild giant panda and its habitat, gives advices for effectively protecting giant pandas and their habitats from human activities, and has implications for the assessment of human activities’ threats to other species in the world.

Trees growing on paved lands endure many environmental stresses in the urban environment. However, the morphological and physiological mechanisms underlying tree adaptation to pavement in the field are less known. In this study, we investigated 40 sites where Ginkgo biloba and Platanus orientalis grow on adjacent pairs of paved and vegetated plots in parks and roadsides in Beijing, China. Relative to the vegetated land, the mean increments in the diameter at breast height and height in the paved land were significantly decreased by 44.5% and 31.9% for G. biloba and 31.7% and 60.1% for P. orientalis, respectively. These decreases are related to both the decrease in assimilation products due to the reductions in leaf area, leaf total nitrogen content, and chlorophyll content and the increase in energy cost due to the synthesis of more soluble sugar and proline for mitigating stress. The increase in leaf soluble sugar content, proline content, and δ13C indicated that trees could adapt to the paved land through the regulation of osmotic balance and the enhancement of water-use efficiency. Piecewise structural equation models showed that trees growing on the paved land are stressed by compounding impacts of the leaf morphological and physiological changes. Therefore, it is critical to explore the complex response of plant morphological and physiological traits to the pavement-induced stress for improving tree health in urban greening.

The continuous decline of global biodiversity highlights the need for the expansion and improved performance of protected areas (PAs) to achieve the Post-2020 Biodiversity Targets and 2030 Sustainable Development Goals. China proposed the establishment of a national park (NP) system and carried out transformative explorations in 10 pilot NPs, however, it is unclear to what extent the pilot NPs represent China’s biodiversity and resolve management issues. To answer this question, we assessed the performance of the pilot NPs by analyzing the representativeness across typical ecosystems, biodiversity priority areas, and ecosystem services, and by analyzing the management effectiveness of reorganizing the existing PAs and improving the management intensity and man-land relationships. We found that China’s pilot NPs achieved improved representativeness and management effectiveness through range expansion and optimization, institution streamlining, and cohesive management. Compared with the existing PAs, the area of protected typical ecosystems, biodiversity priority areas, and key areas of ecosystem services in the 10 pilot NPs increased by 59.6%, 59.6%, and 54.1% on average, respectively, with a similar land cost overall. The 10 pilot NPs integrated 142 existing PAs of seven categories. The protected areas expanded by 19.4%, and the area under strict protection increased by 42.1%. Additionally, the pilot NPs effectively reduced human disturbance and improved management effectiveness through necessary relocation and enhanced land management. Moving forward, the boundaries and zoning of the NPs should be further optimized, and efforts should be directed to strengthen the governing capacity building, improve the legislation system, increase the financing investment, and promote the value realization of ecological products.

The conservation of native species through the establishment and management of nature reserves needs to take into account the effects of anticipated climate change. Species Distribution Models (SDMs) can be used to obtain key information on the spatiotemporal dynamics of species distributions, which is crucial for management strategies. For two ungulates native to Qinghai-Tibet Plateau, Tibetan gazelle (Procapra picticaudata) and Kiang (Equus kiang), we developed a novel two-step SDM framework with an intermediate step that quantifies the suitability of grassland habitats as essential food availability in the Three River Sources Region (TRSR). We then applied the multi-model inference and bootstrapping techniques to improve accuracy and to estimate uncertainty. We found the best models of grassland suitability included growth degree days, aridity, and topographical roughness as predictors; while common predictors of ungulate distributions included grassland suitability, coldest month temperature, and topographical roughness. The potential ranges of both ungulates will gradually move westward, northward, and upward in the TRSR under two climate change scenarios (SSR245 and SSR585). Within current local reserve boundaries in the TRSR, two focal ungulates would nearly go local extinction in the end of this century in SSR585. However, the northwest corner of the TRSR would become a new distribution center in SSR245 and deserves a higher priority for conservation. In addition to a greenhouse gas reduction agenda to curb the warming trend, our findings advocate adaptive management practices regarding spatiotemporal dynamics of wildlife distributions to prevent the extinction of native species and to increase resilience to climate change.

Although biodiversity has been shown to profoundly affect ecosystem function in forests, the processes which it impacts are limited understood. Various plant species with diverse sizes interact to form complex networks to complete resource use processes, but little is known about the role of species-size networks in influencing ecosystem function and biodiversity-ecosystem function relationships. Using a dataset encompassing 423 species and 32,067 individuals, we constructed species–tree diameter and species–tree height networks for two sampling areas (0.04 and 0.09 ha), and then calculated the network modularity for species and size interlinked specialization and nestedness, species or sizes with relatively few links are a subset of those with more network links. We analyzed the relationships between modularity, nestedness, and the aboveground biomass. The direct and indirect effects of species abundance and richness on the aboveground biomass through network structures were explored using structural equation modelling. Regardless of the species–tree diameter or height network, modularity was positively associated with the aboveground biomass, independent of the sampling area, while nestedness was negatively associated. Species abundance negatively affected the modularity, but positively affected nestedness, whereas species richness had the opposite effect. Species abundance and richness affected the aboveground biomass indirectly through modularity and nestedness, but the effect of modularity was greater than that of nestedness. Our study confirms that the importance of species–size networks in the context of the aboveground biomass has similar effects on species–diameter and height networks across sampling areas. It clarifies that modularity from interactions between species and individuals is a useful indicator to reveal the mechanism by which plant diversity acquires resources for biomass production. These results provide new insights into biodiversity–ecosystem function relationships from a network perspective.

In the context of increasing urbanization and worsening environmental pollution, nonpoint source pollution during high-frequency rainfall has become a major ecological problem that endangers residents in cities. This study takes Shenzhen as an example. On the basis of a large number of soil sample test data, and combined with relevant environmental variables, it has drawn the high-resolution, high-precision spatial distribution maps of soil attributes within the city. In addition, this paper combines the revised universal soil loss equation and the GeoDetector model to evaluate the supply capacity of nonpoint source reduction services in the city’s ecological space and the main driving factors of spatial distribution characteristics for different types of land. The study found that increasing soil point density and combining environmental variables can help improve the accuracy of spatial mapping for soil attributes. The ME, MSE, ASE, RMSE, and RMSSE of spatial mapping all meet the accuracy evaluation criteria and are better than many existing studies; the spatial distribution characteristics of soil attributes and nonpoint source reduction services show significant differences among the whole city, secondary administrative regions, and different types of land; the GeoDetector results show that among the three main types of land use (forested land, industrial land, and street town residential land), topographic factors, habitat-quality factors, and ecosystem types have the greatest impact on the spatial differentiation characteristics of nonpoint source reduction services. Among climate factors, only precipitation factors have the greatest impact on the spatial differentiation characteristics of services. Facing the above factors, the q-values calculated by the GeoDetector are all higher than 10%. The results of this study can provide information for making better decisions on regional ecological system management and soil protection and on restoration work aimed at improving nonpoint source reduction services.

An increasing number of studies have focused on the response and adaptation of plants to urbanization by comparing differences in leaf functional traits between urban and rural sites. However, considerable uncertainties remain because differences in land-use type have not frequently been taken into account when assessing the effect of urbanization on leaf traits. In this study, we sampled the needles of Chinese pine (Pinus tabuliformis Carr.) in areas with three land-use types (roadsides, parks, and neighborhoods) along an urban–rural gradient in Beijing, China to determine the effect of urbanization on leaf functional traits. There were significant differences in the values of leaf functional traits between the needles of the current and previous year and across land-use types. Pines growing on roadsides had leaves with smaller length, width, and area, as well as lower stomatal density, compared with those growing in parks and neighborhoods. This implies that on roadsides, plant capacity to acquire resources (e.g., light and carbon dioxide) was degraded. Stomatal density, leaf width, and leaf P concentration increased with increasing distance from the city center, while leaf K concentration decreased with increasing distance from the city center. Importantly, there were significant differences in the urban–rural gradient of leaf functional traits between leaves of different ages, and across land-use types. Leaf age was the most important factor influencing leaf nutrient traits, while land-use type was the most important factor influencing leaf morphological traits in urban environments. Thus, considering the effects of the plant characteristic and land-use type on traits is important for assessing the urban–rural gradients of plant functional traits.

Previous studies have shown that climatic and anthropogenic factors influence the variations in the stable isotope signature of tree materials in an urban ecosystem. However, the responses of urban trees to various anthropogenic and precipitation interventions are unclear. To fill the research gap, the isotopic composition (δ15N and δ18O) and total nitrogen content of the soil-plant system of urban forests were measured, focusing on typical urban tree species (Populus tomentosa and Ficus virens). The research was done under various land uses in China’s Beijing and Shenzhen megacities (with different humidity conditions). The linear mixed-effect model revealed that the δ15N values in the leaves of roadside Ficus virens were significantly higher than those in urban park sites, away from the road (δ15N difference = 7.2‰). In contrast, Populus tomentosa leaves exhibited a non-significant difference (δ15N difference = −1.8‰). Further regression analysis revealed that the variations in δ15N in tree leaves could be attributed to the proximity to highways, suggesting the influence of vehicle exhaust on δ15N values in roadside trees. The linear mixed-effect model also revealed δ18O values significantly higher in Populus tomentosa leaves than in Ficus virens leaves. To assess the influence of humidity conditions on δ18O values in the leaves, the ratio of the atmospheric and intercellular vapor pressures (ea/ei) of tree canopies was estimated. The result revealed that the ea/ei of Ficus virens was significantly higher than for Populus tomentosa, ascribed to the variation in the humidity conditions of the two megacities. These results highlight that urban trees can potentially serve as bioindicators for atmospheric pollution and humidity. Our findings highlight the ecophysiological responses of urban forests related to N and O as they vary according to traffic exhaust and relative humidity. Consequently, they are potentially valuable indicators of urban atmospheric contamination, forming a nature-based solution for citizen welfare improvement.

Land urbanization has reduced the amount of area for natural ecosystem assets. However, with the development of the social economy, will the quality of natural ecosystem assets be improved? If one comprehensively considers the changes in the area and quality of natural ecosystem assets, is the dominant impact of urbanization on natural ecosystem assets positive or negative? In this study, detailed research is conducted on the area, pattern, quality, and overall situation of the ecosystem assets in the Beijing–Tianjin–Hebei urban agglomeration during the rapid urbanization process. The impact of urbanization on the overall situation of ecosystem assets is also analyzed. The research methods used to generate statistics, accounting, and analysis of the ecosystem assets include ArcGIS, satellite remote sensing images, R language programming, and other data analysis tools. The research results show that: (1) The ecosystem area was dominated by degradation, and the landscape pattern became increasingly fragmented, with the exception of farmland and wetland areas. (2) However, the quality of the natural ecosystem assets was significantly improved, and the overall situation of the natural ecosystem assets was optimized. (3) In addition to the population urbanization rate, the growth in the population density, land urbanization rate, and GDP per unit area had a significant negative impact on the overall situation of natural ecosystem assets. This reminds people that the improvement in asset quality can compensate for the reduction in area to some extent, and, in addition to the population urbanization rate, the levels of population density, land urbanization, and economic density should be appropriately controlled.

An increasing number of studies have found differences in the diversity of plant functional traits between urban and rural sites as a result of urbanization. However, the results remain inconsistent. In this study, we measured morphological and nutrient traits of 11 common woody plants along a continuous urban–rural gradient in Beijing, China. Leaf size (e.g., length, width, and area), specific leaf area, and leaf nitrogen and potassium contents decreased gradually and significantly along the urban–rural gradient, indicating that urbanization can enhance the capacity of plants to acquire resources for growth and production. Furthermore, soil nutrients and air temperature decreased along the urban–rural gradient, while air relative humidity increased. A structural equation model showed that these alterations in physical factors attributable to urbanization contributed directly or indirectly to changes in leaf functional traits, implying that changes in soil nutrients and micro-climate induced by urbanization may affect plant growth and production because of the improvement in resource acquisition capacity.

Roads have diverse influences on surrounding biodiversity, especially birds. Here, we evaluated the ecological influences of a highway on avian diversity in the Erka Wetland Reserve (Inner Mongolia, China) to guide future road construction projects. Here, avian and plant surveys were conducted along 51 strips spread over nine transects with different habitat matrixes (including degraded grassland habitat). Nineteen bird species were identified, of which 84% were breeding. Alaudidae was the dominant genus, and is a typical, grassland bird guild. Bayesian analyses showed that Alaudidae density was explained by the interaction between distance from the road and vegetation coverage. Alaudidae density increased with increasing road distance only when the vegetation coverage was at least 35%. However, the height of dominant plants had a negative and significant effect on birds. In addition, endangered birds and some common bird species were absent within the road effect zone. We suggest that future road construction in wetland areas should address the direct and combined effects of roads and habitat configuration (and changes) on birds, in a way that enhances both avian diversity and wetland biodiversity conservation as a whole.

Global climate change and extensive socio-economic development both act to decrease the ground cover in the semi-arid sandy grasslands of Horqin district, northern China. Loss of ground cover increases the direct exposure of the surface soil to erosion by strong winds—a process that ultimately converts grassland into sandy desert. Three ways to restore such degraded lands through afforestation were evaluated in terms of total carbon stored in the restored ecosystems compared to that in the control. Total carbon comprised that stored in the biomass of trees, herbs, standing litter, and soil (to a depth of 100 cm). The three restoration treatments were (1) enclosing the grassland within a shelter belt of Populus × beijingensis (FG), (2) afforesting small but well-distributed patches within the grassland using Pinus sylvestris var. mongolica (MG), and (3) afforesting small but well-distributed patches within the grassland using Ulmus pumila (UG). A plot of desertified sandy grassland in which the dominant species were Agriophyllum squarrosum (Linn.) Moq. and Cenchrus echinatus Linn. was used as the control (CK). The results show that total ecosystem carbon storage in FG, UG, and MG increased significantly over time in comparison with that in CK. After more than 20 years, all three grassland restoration approaches are expected to contribute greatly to global ecosystem carbon sequestration. The rank order of total ecosystem carbon storage content is: FG (104.29 t/ha) > MG (102.96 t/ha) > UG (92.24 t/ha) > CK (24.48 t/ha). Soil carbon storage in the 0–30 cm and 0–50 cm depth ranges accounted for 41.81–60.13% and 59.42–80.80% of the total soil pool, respectively, across all treatments. FG had the highest biomass carbon storage, which was linked to differences in tree species. The structure of the plant community created in these treatments was different from that found in natural stands of forest and in grasslands without trees or shrubs. All the three treatments are suitable for the restoration of moderately desertified sandy grasslands in south-eastern Horqin, northern China, depending on the availability of water and soil nutrients. The results of the present study highlight the importance of degraded grassland restoration programs in enhancing ecosystem carbon storage.

Dynamic monitoring of forest ecosystem quality is necessary for restoration program evaluation but remains challenging for very large-scale programs. Current evaluation methods employ regional forest quality indicators that compare the quality status of targeted forests with benchmarks from remnant old-growth forest communities, however data availability usually limits the application of available methods to small scales. We constructed an improved framework, integrating forest site classification selection and local remnant old-growth forest community delimitation, to quantify and map forest quality using environmental data and remote sensing (RS) based approaches. A classification strength model was introduced to improve the accuracy of forest site classification. The remote-sensing-based method integrates species composition and forest biological productivity characteristics recognition to develop a practical tool for large-scale remnant old-growth forest community delimitation. The new assessment framework was tested across the entire spatially heterogeneous Yangtze River Basin, the largest watershed in China and showed high accuracy in forest quality assessment based on observed field data validation. The forest site classification was selected by considering spatial heterogeneities in climate, topography and soil type, with 37 forest sites classified. The native forest community groups with less human disturbance in each forest site used for forest quality baseline estimation were also selected as forests with top 10% of biomass in protected areas. The case study demonstrated that forest areas of low and poor quality accounted for 34.46% of the total forest area in 2015. Between 2000 and 2015, 55.72% of forest areas experienced increases in quality level, and 7.07% experienced decreases. The improved forest quality assessment framework enhances the scope and accuracy of forest restoration information and can be applied as an evaluation tool for forest restoration management.

Terrestrial ecosystems play a critical role in the global carbon cycle and climate change mitigation. Studying the temporal and spatial dynamics of carbon sink and the driving mechanisms at the regional scale provides an important basis for ecological restoration and ecosystem management. Taking the Dongting Lake Basin as an example, we assessed the carbon sinks of forest and shrub from 2000 to 2020 based on the maps of biomass that were obtained by remote sensing, and analyzed the dynamics of carbon sinks that were contributed by different biomass carbon density levels of constant forest and shrub and new afforestation over the past two decades. The results showed that the carbon sink of forest and shrub in the Dongting Lake Basin grew rapidly from 2000 to 2020: carbon sink increased from 64.64 TgC between 2000 and 2010, to 382.56 TgC between 2010 and 2020. The continuous improvement of biomass carbon density has made a major contribution to carbon sink, especially the carbon density increase in low carbon density forests and shrubs. Carbon-dense forests and shrubs realized their contribution to carbon sink in the second decade after displaying negative carbon sink in the first decade. Carbon sink from new afforestation increased 61.16% from the first decade to the second decade, but the contribution proportion decreased. The overall low carbon density of forest and shrub in the Dongting Lake Basin and their carbon sink dynamics indicated their huge carbon sequestration potential in the future. In addition to continuously implementing forest protection and restoration projects to promote afforestation, the improvement of ecosystem quality should be paid more attention in ecosystem management for areas like Dongting Lake Basin, where ecosystems, though severely degraded, are important and fragile, to realize their huge carbon sequestration potential.

Background: Being an excellent indicator of habitat quality, birds are more and more popular in urban studies. Selective impacts of urban environments on avian communities have been repeatedly demonstrated, however, limited information is available under a spatial-temporal perspective, especially for subtropical young cities. Methods: Bird communities were surveyed and environmental data were collected in different types of urban green spaces surrounded by urban matrix during 2018 and 2019. Various statistical analyses were used to describe avian communities residing in different habitats and evaluate bird–environment relationships. Results: Avian community structure differed between major habitat types. At intensely urbanized roadside green spaces sites, omnivores dominated over insectivores, which were regional dominators. Woodland area was key in all urban habitat types, however, the importance decreased with increasing woodland size. Bird species richness in residential parks and individual abundance in roadside green spaces were negatively influenced by environmental noise and visitor density, respectively. Resident bird species and individuals dominated over migrants, and municipal parks presented higher species richness and abundance than other habitat types during winter. Conclusions: Highly simplified habitats in urban areas represent poor wintering habitats, whereas municipal parks served as key refugia. Continued urbanization will place further pressure on habitats which are more natural; thus, municipal parks and other natural habitats must be protected to construct sustainable human-coupled ecosystems.

Introduction: Culturally protected forests (CPFs), preserved and managed by local people on the basis of traditional practices and beliefs, have social and ecological functions. Local residents’ perceptions were investigated in three types of CPFs (community forests, ancestral temple forests, and cemetery forests) in five villages in southeast China. In semi-structured interviews (232 questionnaires), residents were asked about their perceptions concerning ecosystem services and protection of CPFs. Outcomes: The survey results showed that resource utilization was not high in CPFs than in forests without culturally protected. Important ecosystem services provided by CPFs included air quality improvement, water retention, recreation, and aesthetic value. Respondents were satisfied with different cultural services provided by CPFs, including aesthetic value of community forests, ecotourism of ancestral temple forests, and cultural heritage of cemetery forests. Informal rules and traditional customs were used as the main measures to govern forests in daily life; however, the most effective measures, in order of importance, were setting fines or punishment by laws, using informal rules and village regulations, or protection by government agencies. Only half of the respondents were willing to pay for maintaining ecosystem services of CPFs, but 77.8% respondents were willing to spend time on protection. From apolicy perspective, educational programs were as important as traditions, and they are crucial to explain the ecological importance of CPFs. Conclusion: The conservation of biodiversity and ecosystem services of CPFs will benefit if government agencies consider incorporating CPFs into policy and legislative frameworks, maintain CPFs as collectively owned forests, and introduce ecological compensation mechanisms.

The data presented in this article relates to the research article entitled “Nitrous oxide emissions from soils under traditional cropland and apple orchard in the semi-arid Loess Plateau of China” (https://doi.org/10.1016/j.dib.2016.08.027) (Pang et al., 2019). The dataset includes soil N2O emissions for two land use types (wheat field and apple orchard) in the semi-arid Loess Plateau and related environmental factors, such as soil temperature and soil moisture. In addition, the estimated annual average and seasonal cumulative emissions of N2O are presented here. Nitrous oxide emissions were measured by static, closed chamber methods. The data provides evidence for the difference in N2O emissions among two dominant land uses on the Loess Plateau of China.

Climate change and human activities exert a wide range of stressors on urban coastal areas. Synthetical assessment of coastal vulnerability is crucial for effective interventions and long-term planning. However, there have been few studies based on integrative analyses of ecological and physical characteristics and socioeconomic conditions in urban coastal areas. This study developed a holistic framework for assessing coastal vulnerability from three dimensions - biophysical exposure, sensitivity and adaptive capacity - and applied it to the coast of Bohai Economic Rim, an extensive and important development zone in China. A composite vulnerability index (CVI) was developed for every 1 km2 segment of the total 5627 km coastline and the areas that most prone to coastal hazards were identified by mapping the distribution patterns of the CVIs in the present and under future climate change scenarios. The CVIs show a spatial heterogeneity, with higher values concentrated along the southwestern and northeastern coasts and lower values concentrated along the southern coasts. Currently, 20% of the coastlines with approximately 350,000 people are highly vulnerable to coastal hazards. With sea-level rises under the future scenarios of the year 2100, more coastlines will be highly vulnerable, and the amount of highly-threatened population was estimated to increase by 13–24%. Among the coastal cities, Dongying was categorized as having the highest vulnerability, mainly due to poor transportation and medical services and low GDP per capita, which contribute to low adaptive capacity. Our results can benefit decision-makers by highlighting prioritized areas and identifying the most important determinants of priority, facilitating location-specific interventions for climate-change adaptation and sustainable coastal management.

Residential communities are the primary living spaces for people in China. Their associated greenspaces are important elements of the urban ecosystem, providing neighborhood ecosystem services and hosting bird populations of differing community structures compared with other urban green areas. This study analyzes avian community characteristics within residential communities and their differences compared with urban parks in Beijing. Furthermore, we assess the key environmental factors determining species composition and population sizes and the spatial scales at which these factors are most significant. We randomly selected 27 residential communities to assess the habitat structure and landscape characteristics that underpin residential avian assemblages across multiple spatial scales. Independent sample t-test and model selection methods based on AICc were used for data analysis. Eurasian Tree Sparrow (Passer montanus) (hereafter ETS) alone accounted for 91.0% of total individuals. Compared with urban parks, more migrants and omnivores were found in residential communities. Within-site forest patch connectivity simultaneously decided resident species diversity and individual abundance, with the exception of ETS. Tree species richness and coverage are key predictors for resident species richness and ETS numbers, respectively. Even in the most urbanized species, ETS retained ecological attributes found in “wilder” settings. Residential communities skewed toward avian communities with dominant numbers of ETS. In these low-quality habitats, our results suggest that landscape configuration is more important than local habitat structure. Within-site habitat connectivity and the number of surrounding forest patches with shorter between-patch distances deserve more attention in future landscape design for residential communities.

Introduction: Effective provision of ecosystem services (ES) and improvements in well-being of residents can be realized through policy interventions of stakeholder behavior. Of the several policies, market-based instruments (MBIs) have become the focus of global attention. Outcomes/others: To couple the theory with practice and solve the key problem of unclear definition of property rights, the framework of MBIs is designed. First, property rights of market creation must be clearly defined, verifiable, transferable, enforceable, and have policy continuity. Then, four key characteristics of MBIs need to be considered in the case design, namely those involving ES, stakeholders, trading mechanisms, and guarantee mechanisms. The Pledge Financing of the Right of the Ecological Public Welfare Forest (PFREPWF) in Lishui City is a typical case of China’s current marketization, which is a supplement and improvement to the ecological compensation policy. Based on clearly defined contract rights, Lishui City has realized the integration of ecological compensation and credit creation. Discussion: The case design still has the problems of lack of quantification and lack of correlations with ES. Conclusion: The theoretical and practical analysis around the market mechanism has reference value for solving market failures and providing environmental services.

Air quality issues caused by nitrogen dioxide (NO2) have become increasingly serious in Chinese cities in recent years. As important urban green infrastructure, urban forests can mitigate gaseous nitrogen pollution by absorbing NO2 through leaf gas exchange. This study investigated spatiotemporal variations in the NO2 removal capacity of urban forests in Beijing city from 2014–2019, based on the i-Tree Eco deposition model. The results show that the annual removal capacity of administrative districts within Beijing city ranged from 14,910 to 17,747 tons, and the largest capacity (2684 tons) was found in the Fangshan district. The annual removal rate of NO2 by urban forests in administrative districts within Beijing was estimated at between 0.50–1.60 g/m2, reaching the highest (1.47 g/m2) in the Mengtougou district. The annual average absorption of NO2 by urban forests can account for 0.14–2.60% of annual total atmospheric NO2 and potentially reduce the NO2 concentration by 0.10–0.34 µg/m3 on average. The results of a principal component analysis suggest that the distribution of urban forests in Beijing is not optimized to maximize their NO2 removal capacity, being higher in suburban areas and lower in urban areas. This study provides insights into botanical NO2 removal capacity in Beijing city to mitigate atmospheric N pollution, addressing the key role of urban forests in improving human wellbeing.

The overgrowth of reactive nitrogen emissions (Nr, all species of nitrogen except N _2 gas) is a major cause of environmental pollution, especially in rapidly urbanizing regions. The nitrogen footprint (NF) indicator has been widely used to assess Nr losses occurring from the consumption of food and energy. We undertake the first attempt to apply NF methods to explore the spatial-temporal NF characteristics of major urban agglomerations in China between 2000 and 2019, and find that the highest level of annual NF (average 3868 Gg N yr ^−1 ) was produced by the Yangtze River Delta urban agglomeration (YRDUA), followed by the Beijing–Tianjin–Hebei urban agglomeration (BTHUA) (average 2657 Gg N yr ^−1 ). Their NF growth rates showed similar downward trends during the study period, while the Pearl River Delta urban agglomeration (PRDUA) (average 1528 Gg N yr ^−1 ) retained a higher growth rate. The average proportions of food NF (FNF) in BTHUA, YRDUA and PRDUA were 57.64%, 68.64% and 66.79%, respectively. Compared to the FNF, the energy NF gradually plays a more important role in China’s urban agglomerations compared to other countries. Analysis of the underlying drivers showed that an increasing urbanization rate boosted the NF of YRDUA, and rising GDP per capita significantly contributed to the NF growths of BTHUA and PRDUA. Through scenario analysis, we found that shifting to healthy dietary patterns and a partial substitution of fossil fuels with clean energy, as well as improvements in rural wastewater treatment, could contribute to NF reductions by 2030. The largest potential NF reduction is predicted in PRDUA (29% reduction), followed by YRDUA (23% reduction) and BTHUA (18% reduction). The energy reduction scenario is considered to be the most realistic in reducing the NF. We demonstrate the potential of the NF as a tool for the assessment of sustainable development in urban agglomeration, which may prove instructive for broader research on sustainable Nr management.

Land-use intensification impairs multiple soil ecosystem functions and services (hereafter ‘soil multifunctionality’; SMF) crucial to human wellbeing by influencing plant diversity and soil microbial communities. However, available information is limited on the contrasting and interaction effects of plant diversity and soil microbial communities on SMF under a gradient of land-use intensity (LUI). We measured five soil ecosystem functions associated with effective soil nutrients and water retention along 15 LUI gradients on Hainan Island, where land-use change and biodiversity loss has been severe. We used phospholipid fatty acid (PLFA) method to determine the diversity and composition of soil microbial communities. The relationships among LUI, plant diversity (species and functional diversity), soil microbial diversity (bacterial and eukaryotic diversity), and soil microbial composition (fungi/bacteria and Gram-positive/Gram-negative bacteria ratios), and SMF were examined. The LUI affected SMF indirectly by reducing plant diversity and its interaction with soil bacterial diversity. Specifically, with increase in LUI, loss of plant species diversity indirectly reduced SMF via reduction of soil bacterial diversity. In contrast, loss of tree height diversity reduced SMF directly and indirectly through decrease in soil bacterial diversity. Importantly, the indirect effect of LUI mediated by tree height diversity was stronger than that mediated by plant species diversity and soil bacterial diversity. These results provide evidence that the cascade effect of plant diversity to soil bacterial diversity mediates the impacts of land-use intensity on soil multifunctionality, and further suggest that focusing on tree height diversity may be helpful for sustainable ecosystem management and predicting the impacts of land use changes. Keywords: Land use change, Biodiversity, Trophic levels, Ecosystem services, Ecosystem multifunctionality

Ecological benefits provided by ecosystem assets play an important role in improving human wellbeing. However, there are few feasible methods to combine data on the quantity and quality of ecosystem assets to describe their state and trend. Here, we developed a new remote-sensing-based indicator by synthesizing ecosystem asset quantity and quality data for effective assessment at a regional or national scale. The new indicator includes a typological ecosystem asset index (TEAI) (e.g., forest ecosystem asset index) and an integrated ecosystem asset index (IEAI). The TEAI and IEAI can be used to assess the state and trend of a specific ecosystem or set of regional ecosystems, respectively. We applied the new indicator in the context of ecological protection policy in the Three-Rivers Source Region (TRSR), a region known as the ‘Chinese water tower’. From 2000 to 2015, the IEAI increased by 4.02% due to an increase in the ecosystem asset area (0.2%) and the ecosystem asset quality (0.66% and 0.02% increases in excellent and good level ecosystem assets, respectively). The implementation of ecological protection and ecological restoration programs was the main direct driver of regional ecological asset improvement. Our results suggest the new indicator is feasible for quickly and accurately evaluating the state and trend of ecosystem assets and can be used to guide ecosystem management at a large regional scale.

Background Because of its status as an ecocivilization pilot city, fundamental research on spatial distribution patterns and impact factors of the avian community within the Xiong’an New Area is necessary for future ecological planning and mitigation of negative impacts from future urbanization. Gradient research within small cities can provide important information for the development of urbanization gradient patterns of avian communities. Methods A total of 30 sample points within the urbanization gradient were selected, and avian communities and environmental variables were measured within a 50 m radius sample circle. Principal component regression analysis was used to analyze bird-environment relationships. The Sorensen dissimilarity index was used to calculate the beta-diversity. Results Our results showed that there was a significant urban-rural pattern with a gradient phenomenon in avian communities. Results of this study showed more resident, passenger and insectivore species, and a higher density of breeding insectivore and omnivore individuals appear in the urban fringe than in the other areas. A relatively high value of overall beta-diversity and spatial isolation probably exists among the three disjunct constructed regions. Both species richness and individual abundance were significantly influenced by the species diversity of the trees and foliage height diversity (FHD). Discussion Based on our results and our goal of avian species diversity conservation, we first suggest that urban green spaces be established and ensure a high complexity of vegetation structure as this is critically needed to increase avian species α-diversity within habitat patches. Second, different habitat types within and around the three constructed areas should be developed based on the important existing bird habitats to increase avian diversity in each city, especially in the areas within Xiongxian and Rongcheng that are well protected, and to elevate the beta-diversity of the total region. Finally, based on the biodiversity hotspots identified by this research, ecological corridors should be carefully planned to improve the stability of regional bird communities.

Over 240 migratory water bird species depend on China's 18,000 km coastline as a vital stopover area. However, the rapid loss of natural wetlands has threatened this seasonal water bird migration over the last few decades. In the present study, to improve our understanding of the pattern and amount of habitat loss in key stopover areas (KSAs) and the spatial covariance between habitat loss and economic development, we conducted a spatially explicit evaluation of coastal habitat loss in KSAs and explored its relationship with social and economic dynamics along the China coast by integrating high-spatial resolution satellite imagery with an updated coastal water bird investigation data set. The remote sensing survey detected a habitat loss percentage of 19.4% in the KSAs during 2000 and 2010. Aquaculture, urbanization, and land reclamation were responsible for the most severe disturbances to coastal habitats. These results demonstrate that the losses of wetland habitats in the KSAs in Chinese coastal areas are more severe than those in other coastal areas even though more protective measures have been implemented in these areas. Risk-based analysis showed that the risk of habitat loss was greatest in undeveloped regions with rich natural wetland and large populations, thereby demonstrating the critical importance of shifting the focus of water bird conservation to these regions to ensure the conservation of migratory water birds in the East Asian–Australasian Flyway. These findings disagree with the hypothesis that more habitats are lost when the economy is more developed. Therefore, we suggest that focusing conservation decisions on areas undergoing urbanization might improve the effectiveness of conservation measures given the pressures due to various forms of wetland exploitation. Keywords: China, Coastal zone, Habitat loss, Migratory water bird

Background: Grain security is crucial for social stability and ecosystem conservation regionally and globally, and it is particularly concerned widely in the Qinghai-Tibet Plateau (QTP) due to its high altitude and harsh climate for agriculture. Method: In this paper, we calculated and analyzed per capita food and grain consumption, including direct grain consumption, grain for fodder, industry consumption, seeds consumption, and wastage consumption and its changes in the QTP during 1995–2019. Results: The results showed that (1) in 2019, the average food consumption per capita was 333.35 kg, was stable since 1995. The dietary structure of residents was composed of direct grain consumption (44.15%), meat (10.72%), and milk (6.94%). The consumption of meat and milk was higher than the national average. (2) The average daily intake of energy and protein, animal protein, and the ratio of high-quality protein and fat energy were 2156.21 kcal·d−1, 73.53 g·d−1, 23.06 g·d−1, 38.32%, and 27.77% in 2019. Their changes were −342.98 kcal·d−1, −8.91 g·d−1, 11.16 g·d−1, 18.37%, and 11.08%, respectively. (3) The corresponding grain consumption per capita was 284.90 kg·a−1 in 1995, 262.19 kg·a−1 in 2010, and then remained stable until 2019. Conclusion: The study suggested that food consumption per capital was guaranteed at the well-off level since 2010, and food and dietary structure of residents were corresponding to physical geographic and climatic environment in the QTP. The conflict between food security and the ecosystem conservation can be managed without scarifying nature as the total grain consumption was stable since 2010, and the yield per unit area and total grain yield were both increasing since 2003 for agricultural condition improved in the QTP.

Tropical island countries are often highly populated and deliver immense ecosystem service benefits. As human wellbeing depends on these ecosystems, proper management is crucial in the resource-rich tropical lands where there is less related research. Though ecosystem service and biodiversity studies are a promising path to inform the ecosystem management for these mostly developing countries, published evidence of using ecosystem service studies in decision making is lacking. The purpose of this study is to provide an overview of ecosystem services and related research in Sri Lanka, examining trends and gaps in how these studies are conceptualized. Out of the considered 220 peer-reviewed articles, the majority of articles (48.2%) were terrestrial and forest related while coastal ecosystems were considered in 33.2% of studies. In most studies, the ecosystem service category studied was provisioning (31.5%) followed by regulatory service (28.7%). Studies investigating and quantifying ecosystem services, pressures on ecosystems, and their management were fewer compared to studies related to biodiversity or species introduction. Moreover, studies investigating the value of ecosystem services and biodiversity to the communities or involvement of stakeholders in the development of management actions regarding the ecosystem services were rare in Sri Lanka, and an intense focus from future studies in these aspects is timely and necessary.

Abstract Reforestation is effective in restoring ecosystem functions and enhancing ecosystem services of degraded land. The three most commonly employed reforestation methods of natural reforestation, artificial reforestation with native Masson pine, and introduced slash pine plantations were equally successful in biomass yield in southern China. However, it is not known whether soil ecosystem functions, such as nitrogen (N) cycling, are also successfully restored. Here, we employed a functional microarray to illustrate soil N‐cycling. The composition of N‐cycling genes in soils varied significantly with reforestation method and varied with constructive species identity and plant diversity. Artificial reforestation had less superior organization of N‐cycling genes than natural reforestation, as indicated by the less diverse and less stable pathways to perform the biogeochemical N‐cycling processes. Besides, artificial reforestation had lower functional potential (abundance of ammonification, denitrification, assimilatory, and dissimilatory nitrate reduction to ammonium genes) in soils than natural method. Evaluations of the abundance and interactions of N‐cycling genes in soils showed that plantations, especially artificial reforestation with slash pine plantations, possessed a smaller range of ecosystem functions that provide a less diverse array of N‐related substrates and nutrients to microbial communities compared with natural restoration. This might lead to a lower independence of N‐cycling, which indicated a higher risk of N release in plantations. The unfavorable N‐cycling conditions in plantations were corroborated by the lower contents of available N, ammonium N, and nitrate N. These findings demonstrate that reforestation methods could have broad regional and possibly global implications for N‐cycling.

The spatial heterogeneity of plant diversity at the neighborhood scale has less been understood, although it is very important for the planning and management of neighborhood landscape. In this case study of Beijing, we conducted intensive investigations of the plant diversity in different neighborhoods along a rural–urban gradient. The results showed that the mean numbers of plant species per neighborhood were 30.5 for trees, 18.8 for shrubs, and 31.9 for herbs, respectively. There were significant logarithmic relationships between the numbers of species and patch area, indicating that larger patches within neighborhoods could harbor more plant species. Hierarchical linear modeling showed that the variations in plant diversity within neighborhoods were higher than those between neighborhoods. The number of species increased logistically with both the number of patches within neighborhoods and the number of neighborhoods, suggesting that it is important to sample a sufficient number of patches within neighborhoods, as well as a sufficient number of neighborhoods in order to sample 90% of the plant species during the investigation of plant diversity in urban neighborhoods. So the hierarchical design of sampling should be recommended for investigating plant diversity in urban areas.

The impact of climate change, rising CO _2 , land-use/land-cover change and land management on the carbon cycle in terrestrial ecosystems has been widely reported. However, only rarely have studies have been conducted to clarify the impact of climate change and rising CO _2 on the carbon sink contributed by ecological restoration projects (ERPs). To better understand the impact of climate change and rising CO _2 on ERPs, we took the Beijing–Tianjin Sand Source Control Project zone as an example to set up different scenarios to distinguish the confounding effects of these factors on the regional carbon budget based on a remote sensing data-driven model. Compared with business as usual, our results show that climate change caused a carbon loss of 78.97 Tg C. On the contrary, ERPs contributed a carbon sink of approximately 199.88 Tg C in forest and grassland. Furthermore, rising CO _2 also contributed an additional carbon sink of 107.80 Tg C. This study distinguished the individual effects of different factors, and clarified the net carbon sink contributed by ERPs and rising CO _2 and their significance for enhancing the regional carbon sink and reversing the adverse effects of climate change on the carbon sink. Furthermore, ERPs can sequester carbon more effectively and faster compared with rising atmospheric CO _2 concentration.

Specific forest restoration aims to maximum ecosystem services (ESs); however, the complex trade-offs among ecosystem services pose considerable challenges for fulfilling such goals. Based on forest restoration on Hainan Island, China, we integrated spatially explicit models of ecosystem services and spatial prioritization techniques based on the efficiency frontier between habitat quality and plantation revenue to analyze the impacts of decision-makers’ preferences on optimal configurations of forest restoration. We then investigated the effects of different optimal restoration schemes on water purification, soil retention, carbon sequestration, and coastal hazard mitigation. Based on our results, plantation revenue and habitat quality exhibited an obvious trade-off during the process of restoration. Forest restoration patterns also varied with the degree of preference for plantation yield or habitat quality, indicating that understanding ecosystem service tradeoffs can support the optimal selection of forest restoration schemes under different preferences. However, when the values of multiple ecosystem services associated with forest restoration were considered (e.g., water purification, soil retention, carbon sequestration, and coastal hazard mitigation), the optimal solution choice varied. Our results suggest the application of the efficiency frontier can deepen quantitative understanding of ecosystem service trade-offs, and the addition of multi-benefit evaluation based on optimal solutions can provide a more detailed and broader picture of forest restoration plans. Integrated efficiency frontier assessment with the valuation of ecosystem services associated with forest restoration provides a quantitative approach for optimal forest restoration, which can be applied in broad forest restoration programs.

Plantations support local economies and rural livelihoods in many mountainous regions, where poverty and a fragile environment are often interlinked. Managing plantations sustainably and alleviating poverty is a major challenge. This study reports on the findings of a household livelihood survey in the central mountainous region of Hainan Island, a global biodiversity hotspot. The survey aimed to identify rural household livelihoods, strategies to lift rural households out of poverty and potential environmental consequences of different livelihood strategies. Households were divided into five groups based on their main source of income: plantations, crops, livestock, local off-farm income and remittances. Plantations were the main source of income for 74% of households and provided 46% of the total income. Plantation land area, planting diverse tree species and intercropping were significantly associated with higher income. Reallocating land by family size could increase the proportion of households above the poverty line in the plantation group from 51.3% to 85.3%, while making only 3.3% of households worse off. Lower income households tended to apply more chemicals to plantations, which suggests that they create more strain on the environment. Improving household income through dynamically allocating plantation land and diversifying planted species could therefore be beneficial both socially and environmentally. Our results emphasize the importance of dynamic plantation land allocation and diverse plantation planting in poverty alleviation and environmental sustainability.

Gross Ecosystem Product (GEP) is an aggregate measure of the monetary value of final ecosystem services, or the direct benefits that people derive from nature. In this study, we focus on the ‘Chang-Zhu-Tan’ (CZT) urban agglomeration—an emerging megacity of over 15 million people situated on the Yangtze River—as a case study of the dynamics of ecological production amidst rapid urbanization. In this study, we couple a spatial-temporal analysis of regional ecological change based on remote-sensing data with economic valuation methods (e.g. travel cost method) using official statistics and survey data. We find that while the land cover of natural ecosystems decreased slightly between 2000 and 2015, their quality—and therefore economic value—greatly improved. From 2000 to 2015, the GEP of CZT increased by 56.77%. In particular, the value of regulating services grew by 7.43% (calculated using inflation-adjusted prices). GEP can reflect nature’s contribution to human well-being. At the same time, its long-term trends can serve as an indicator of the extent and quality of local and regional ecosystems, thereby providing a corrective or complement to more conventional measures of development. Although urbanization increases spatial constraints on the management of natural capital, progress in ecological protection and restoration can still improve the quality of ecosystems and the services they provide. Our study shows how GEP, and the value of natural capital it reflects, can grow amidst the pressures of rapid urbanization.

The restoration of ecosystems provides an important opportunity to improve the provision of ecosystem services. Achieving the maximum possible benefits from restoration with a limited budget requires knowing which places if restored would produce the best combination of improved ecosystem services. Using an ecosystem services assessment and optimization algorithm, we find choices that generate maximum benefits from ecosystem restoration. We applied a set of weights to integrate multiple services into a unified approach and find the optimal land restoration option given those weights. We then systematically vary the weights to find a Pareto frontier that shows potentially optimal choices and illustrates trade-offs among services. We applied this process to evaluate optimal restoration on Hainan Island, China, a tropical island characterized by multiple ecosystem service hotspots and conditions of poverty. We analyzed restoration opportunities with the goal of increasing a provisioning service, plantation revenue, and several water-related ecosystem services that contribute to improved water quality and flood mitigation. We found obvious spatial inconsistencies in the optimal location for maximizing separate services and tradeoffs in the provision of these services. Optimized land-use patterns greatly out-performed the non-target restoration scheme. When explicit consideration of the importance of poverty alleviation was taken into account, the location of the prioritized areas shifted and trade-offs among services varied. Our study emphasizes the importance of integrating social concerns into land-use planning to mitigate conflicts and improve equity, especially in the areas where poverty and hotspots of biodiversity and ecosystem services are highly geographically coincident.