Ecosystem Service Function Research Articles

Land Change Simulation and Forest Carbon Storage of Central Yunnan Urban Agglomeration, China Based on SSP-RCP Scenarios

Land use change is closely related to the terrestrial ecosystem. Studying the relationship between land use and ecosystem service carbon storage under future climate change can optimize the regional ecosystem service function and formulate sustainable social and economic development policies, which is of great significance for regional carbon emission management and climate change response. In this paper, the coupled model of SSP-RCP-PLUS-InVEST was constructed to simulate land use change under different scenarios, analyze the influence degree of driving factors on different regions, and explore the spatio-temporal evolution and spatial correlation of carbon storage, taking Central Yunnan City agglomeration as an example. The results showed that: (1) from the perspective of land use change, the overall changes in SSP126 and SSP245 scenarios were similar, and the change rates of different types were slightly different. Under the SSP585 scenario, the forest area decreased, and the urban land and cropland land expanded. (2) Under the three scenarios in the future, the decrease in total carbon storage is the most serious under the SSP245 scenario, and the decrease is the most serious under the SSP585 scenario. (3) Comparative spatial correlation: the carbon storage in the Central Yunnan urban agglomeration is generally correlated among counties, and there is no significant difference under the future scenarios, showing a high accumulation pattern in the east and low accumulation pattern in the middle. In general, reasonable planning of land spatial patterns and increasing the proportion of forest is conducive to the proportion of regional carbon sequestration capacity. The research methods can provide references for addressing climate change and territorial spatial planning.

Nitrogen dynamics in the Critical Zones of China

Nitrogen dynamics at ecosystem levels profoundly impact the Earth’s surface system due to their environmental and ecological significance. Exploring the sources and transformation of nitrogen in various Critical Zones is vital to understanding biogeochemical cycles and sustainable development. This study summarized nitrogen characteristics in soil profiles and nitrogen dynamics in diverse terrestrial ecosystems based on data from typical Critical Zones of China. The results indicated that nitrogen accumulates in the deep soils of cropland ecosystems due to intensive fertilizer applications, which potentially harms soil functions and water quality. Therefore, it is necessary and meaningful to take adequate measures to alleviate nitrogen accumulation in deep soils. Additionally, surplus nitrogen transported into groundwater and riverine systems from soil has emerged as an important issue for environmental management. There are serious nitrogen pollution issues in many river water and groundwater areas, which could be addressed by reducing the fast leaching and considerable nitrogen accumulation in the vadose zone. Systematic and long-term observational studies are needed to achieve the ultimate goal of ecological conservation and high-quality development. Therefore, future research should consider monitoring and evaluating ecosystems based on the long-term Critical Zone Observatories networks to advance appropriate environmental management strategies that adapt to nature’s rules and strengthen the ecosystem service function for sustainable development.

Urban Expansion Was the Main Driving Force for the Decline in Ecosystem Services in Hainan Island during 1980-2015.

Hainan Island is one of China's most ecologically diverse areas. Human activities and climate change have recently influenced Hainan Island's ecosystem services. Therefore, scientific methods are urgently needed to investigate the characteristics of these services' spatial and temporal variations and their driving mechanisms for maintaining Hainan Island's biodiversity and high-quality ecological conservation. Based on multivariate remote sensing and reanalysis data, this study analysed the spatial and temporal variations in water retention, soil conservation, carbon sequestration, and oxygen release services on Hainan Island during 1980-2015 using various ecosystem service models such as INVEST, CASA and RULSE. Then, we analysed different ecosystem service drivers using a random forest model. The results indicated that (1) from 1980 to 2015, the change characteristics of different ecosystem types (arable, forest, and grassland) decreased, and the proportion of decrease was 0.98%, 0.55% and 0.36%, respectively. Built-up and water increased significantly, and the proportion of increase reached 1.46% and 0.51%, respectively. (2) Hainan Island's functions of water retention, soil conservation, carbon sequestration, and oxygen release services decreased from 23.31 billion m3, 2.89 billion t, 9.68 million t and 56.05 million t in 1980 to 23.15 billion m3, 2.79 billion t, 9.42 million t and 55.53 million t in 2015, respectively. The high value area was mainly distributed in Hainan Island's central mountainous area, and the low value area was mainly distributed in the lower-elevation coastal area. (3) In the past 35 years, urban expansion has been the leading factor in the reduction of Hainan Island's ecosystem service capacity. However, its central nature reserve and other forms of ecological protection have improved its ecosystem service capacity, which has alleviated the overall declining trend of its amount of ecosystem service functions. (4) The driving forces for the spatial distribution of Hainan Island's ecosystem services were analysed using a random forest algorithm, which indicated that its spatial distribution was mainly driven by rainfall, soil moisture, actual evapotranspiration, maximum temperature, and minimum temperature. This study is expected to help planners develop effective environmental policies to accommodate the potential ecological risks associated with urban expansion during the construction of Hainan Island's future free trade port while filling the gaps in existing studies.

Long-Term Spatiotemporal Changes in Ecosystem Services Caused by Coastal Wetland Type Transformation in China’s Hangzhou Bay

Coastal wetlands provide essential ecosystem services, while usually experiencing land transformation or degradation mainly due to intense anthropogenic activities and climate changes. Understanding the changes in wetlands ecosystem services is essential to decision makers for generating sound coastal planning. Hangzhou Bay is rich in wetland resources, and the urbanization of Hangzhou Bay in the past three decades has caused fundamental changes in the wetlands in the region. Based on the remote sensing images of the Hangzhou Bay area from 1990 to 2020, this paper analyzes the land use situation of the Hangzhou Bay area in seven periods. This paper calculates the area transfer matrix of various types of wetlands. It uses the InVEST model to evaluate the changes in the function of wetland ecosystem services in the Hangzhou Bay area. Hangzhou Bay wetlands show a trend of transferring natural wetlands to artificial and non-wetlands from 1990 to 2020. Carbon stocks fell by 14.24%. The annual water production decreased by 33.93% and then returned to the original level. The area of habitat degradation increased by 79.94%. The main influencing factors are paddy field degradation, increase in non-wetland area, and decrease in sea area. This paper proposes that the development and construction of farmland in the “red line” area and established wetland reserves are prohibited, and to strengthen the training of wetland management personnel, establish a sound decision-making consultation mechanism, and increase the scientific research expenditure on wetlands in the region.

Identification of Typical Ecosystem Types by Integrating Active and Passive Time Series Data of the Guangdong-Hong Kong-Macao Greater Bay Area, China.

The identification of ecosystem types is important in ecological environmental assessment. However, due to cloud and rain and complex land cover characteristics, commonly used ecosystem identification methods have always lacked accuracy in subtropical urban agglomerations. In this study, China's Guangdong-Hong Kong-Macao Greater Bay Area (GBA) was taken as a study area, and the Sentinel-1 and Sentinel-2 data were used as the fusion of active and passive remote sensing data with time series data to distinguish typical ecosystem types in subtropical urban agglomerations. Our results showed the following: (1) The importance of different features varies widely in different types of ecosystems. For grassland and arable land, two specific texture features (VV_dvar and VH_diss) are most important; in forest and mangrove areas, synthetic-aperture radar (SAR) data for the months of October and September are most important. (2) The use of active time series remote sensing data can significantly improve the classification accuracy by 3.33%, while passive time series remote sensing data improves by 4.76%. When they are integrated, accuracy is further improved, reaching a level of 84.29%. (3) Time series passive data (NDVI) serve best to distinguish grassland from arable land, while time series active data (SAR data) are best able to distinguish mangrove from forest. The integration of active and passive time series data also improves precision in distinguishing vegetation ecosystem types, such as forest, mangrove, arable land, and, especially, grassland, where the accuracy increased by 21.88%. By obtaining real-time and more accurate land cover type change information, this study could better serve regional change detection and ecosystem service function assessment at different scales, thereby supporting decision makers in urban agglomerations.

Assessing the impacts of ecological governance on carbon storage in an urban coal mining subsidence area

Carbon storage, which is considered one of the important service functions of ecosystems, plays an irreplaceable role in maintaining the regional carbon balance and regulating the climate. Regional carbon storage is closely related to regional land use and land cover (LULC). With the development and expansion of coal resource-based cities, the construction areas of cities have started to overlap with underground coal resources. Coal mining leads to regional LULC changes, such as large-scale surface subsidence and subsidence waterlogging, and LULC has changed and consequently affected carbon storage in urban coal mining subsidence areas. This study analyses the change trend of carbon storage and clarifies the effect of ecological governance being implemented in the urban coal mining subsidence area. First, the LULC change map of the ecological governance scenario was obtained via remote sensing technology. Then, the natural evolution scenario from 2000 to 2021 was simulated using the hybrid cellular automata and Markov chain, also named the CA–Markov model. Finally, combined with the subsidence waterlogging in the urban subsidence area, the InVEST model was used to analyse the spatial–temporal variation characteristics of carbon storage. The analysis results showed that LULC and carbon storage in small-scale urban coal mining subsidence areas changed dramatically between 2000 and 2021 due to coal mining and ecological governance. The subsidence waterlogging area increased by 1033.83 ha, resulting in total carbon storage decreasing by 37,560.21 t. Subsidence waterlogging is the key influencing factor in the decrease in carbon storage. The forest area increased by 1270.83 ha, resulting in a total carbon storage increase of 216,531.04 t. Forest is the crucial increasing factor in carbon storage. The changes in carbon storage in the urban coal mining subsidence area can be classified as follows: obvious improvement area, basically unchanged area, and significantly degraded area. As opposed to the natural evolution scenario, the ecological governance scenario increased the coverage of the “obvious improvement area” by 818.46 ha in the urban coal mining subsidence area. Overall, this study illustrates that ecological governance can effectively improve carbon sequestration and is conducive to the healthy development of coal resource-based cities.

Hydrology and Nutrient Dynamics in Managed Restored Wetlands of California’s Central Valley, USA

Extensive wetland losses in California’s Central Valley have led to significant reductions in their natural functions, such as nutrient removal. Past studies suggest that individual wetland restoration efforts in the region yield mixed results mainly due to differences in management practices and degree of access to limited water resources, yet few studies have examined their hydrology or nutrient dynamics with any detail. Our objective was to explore nutrient reduction across a range of hydrological regimes. We recorded hydroperiods and nutrient concentrations of the received and discharged applied water at 21 managed wetlands on national wildlife refuges and private lands over 6 years from 2015 to 2020. Water depths at 18 of these wetlands were monitored continuously for over 400 days. Climatic variation over the observation period included exceptional drought, above-average flooding and relatively stable water conditions. Privately managed wetlands retained water for longer durations of time, but at shallower depths than seasonal wetlands in wildlife refuges. An assessment of nutrient concentrations at inflows relative to outflows was inconclusive and varied among years. However, assessment of nutrient loads indicated consistent retention of ammonium and nitrates across all management types, locations and time periods. Multivariate analysis indicated that climate and location played a role in influencing nutrient concentrations among wetlands. In conclusion, restored wetlands in the central valley provide ecosystem service functions such as removing nutrients from ambient water and provide unique habitats for waterfowls with the presence of seasonal flood and drain management practices.

Transformation Path of Ecological Product Value and Efficiency Evaluation: The Case of the Qilihai Wetland in Tianjin.

In order to protect wetland resources, China has developed wetland conservation policies and has made significant conservation investments, but there is still a lack of pathways for the conversion to economic value, making it difficult to meet the demand for continuous investment. We have explored a sustainable ecological conservation mechanism using the Seven Mile Sea as a case study, so that ecological conservation costs can be transformed into economic development behaviors and ecological benefits and socio-economic development can be integrated. This paper assesses the ecological product value of the Qilihai Wetland based on the ecosystem service function value assessment method, which designs the realization path of ecological product value and predicts the value transformation efficiency. The results show the following: (1) The total value of ecological products in the study area is CNY 569.06 million (USD 78.36 million), and the main sources of value are plant products in the supply service and water purification functions in the regulation service, accounting for 54.05% and 26.10% of the total, respectively. (2) The predicted value realization of ecological products, ideally, is CNY 689.65 million (USD 94.96 million), with a value realization rate of 111.60%. Considering the management policy restrictions in different areas of the Qilihai Wetland, the actual value realization volume is CNY 391.94 million (USD 53.97 million), with a value realization rate of 63.42%. (3) Owing to the restriction of the development policy of supply services and cultural services, the value realization path mainly contains two types: one is to drive the development of supply services and cultural services in the surrounding areas, along with product premiums, to realize value transformation. This path is mainly aimed at the supply of local characteristic products and the development of tourism. The second is to realize the value of regulating services through ecological compensation and ecological equity trading. This path is mainly for the adjustment and support services in the core area and buffer area. According to the pre-accounting results, the contribution rates of the two paths are 62.25% and 37.75%, respectively. The second path should be further effectively developed to improve the contribution rate. This study helps assess the ecological value and important ecological elements of the Qilihai Wetland to ensure effective protection and development of important ecological resources and to achieve the sustainable development of wetland resources. It provides a reference for exploring feasible paths to realize the value of ecological goods.

Effects of Structural and Diversity Attributes on Biomass in Different Types of Urban Forests in Changchun, Northeast China, and Suggestions for Urban Forest Planning

Understanding of the relationship between structural and diversity attributes and biomass is important for plant biodiversity conservation, ecosystem service function enhancement and sustainable development of urban forest ecosystems. In this study, road forest (RF), attached forest (AF) and landscape and relaxation forest (LF) were selected as research objects. We systematically evaluated the diversity attributes and above ground biomass (AGB) at two dimensions of different diameter at breast height (DBH) grades and different tree height grades of urban forests in Changchun, Northeast China. Structural equation modeling (SEM) analyses of the correlation between structure attributes, diversity attributes and biomass among different types of urban forests were carried out. The results showed that species richness (SR) and Shannon–Wiener index (H′) of shrubs were lower than those of trees. Under the DBH grades, H′ in each forest type was highest in the 0–10 m grades and SR was highest in the 10–20 m grades. Under tree height grades, both H′ and SR of each type were at the top of the list. AGB was highest in each forest type under 5–10 m height grades. The relationship between AGB and H′ was better in LF, but with no significant relationships in the other forest types. SEM highlighted that in the overall aspect, the effect of forest type on biomass was mediated by structure and diversity attributes. Particularly in LF, there were direct and indirect effects between structure attributes and biomass mediated by diversity attributes. The improvement of the H′, evenness index (J′) and SR could enhance urban forest services, especially for the biomass and diversity of LF.

Multi-Scenario Simulation of Ecosystem Service Value in Wuhan Metropolitan Area Based on PLUS-GMOP Model

Rapid construction and development activities in large urban areas have significantly impacted land use and land cover (LULC). They have brought great pressure to urban sustainable development. Current studies have shown that changes in LULC structure significantly affect regional ecosystem service functions but lack the sufficient scientific basis to provide reasonable strategies for the future development of urban areas. Based on land use and related data for the Wuhan metropolitan area (WMA) in 2000, 2010, and 2020, in this study, we construct a land use and ecosystem service value (ESV) simulation method based on a coupled PLUS-GMOP (patch generation land use simulation and grey multi-objective optimization) model and find that the changes in LULC structure from 2000 to 2020 are mainly reflected in the decrease in farmland and water area and the increase in built-up land, which are spatially reflected in Wuhan city center and other surrounding urban centers. The ESV also exhibits a slight increase and then a significant decrease, and a consistent overall pattern of high in the west and low in the east. By presupposing three scenarios for 2030 (ND, natural development; EFD, ecological first development; EECD, ecological and economic coordinated development), the analysis shows that although the ecological service value is still decreasing, the EECD scenario achieves a relatively high economic value (+90.134 billion yuan) by losing less ecological service value (0.27 million yuan) than EFD, which is the development model advocated in this study. The PLUS-GMOP coupling model proposed in this study provides a scientific reference for coordinating regional economic development and ecological protection in large cities, and provides a new technical path for metropolitan area sustainable development and planning.

Study on the Evolution Mechanism of Ecosystem Services in Karst Mountainous Areas from the Perspective of Humanities.

Anthropogenic activities have altered ecosystem service functions in the karst mountainous areas. The implementation of ecological restoration projects by the government, the behavior, attitude, and willingness of farmers to participate in their implementation, the application of pesticides and fertilizers, in addition to other socio-economic activities, have had a significant impact on the ecosystem services (ESS) of the region. Taking Guangnan County, a typical karst mountainous area in Yunnan Province, as an example, this study analyzes the evolutionary characteristics of six types of ESS and the driving mechanism of the change in ESS from the anthropogenic macro and micro perspective using questionnaire surveys and the multivariate logistic model. The results showed that (1) ecological restoration projects in the past 20 years have promoted an overall ecological transformation in the typical karst mountainous areas of the Yunnan Province (2) from the macro perspective, and the implementation of such ecological projects is beneficial in increasing soil conservation, carbon sequestration, habitat support, and cultural services. The reduction in agricultural population is beneficial in improving habitat support services, and the increase in the annual average tourism income and the tertiary industry is beneficial in increasing cultural services. Among them, the impact of hydraulic engineering on water production and the tertiary industry on cultural services are the most significant, with the change in the human disturbance index having the most substantial impact on soil conservation, carbon sequestration, and habitat support (3) at the micro level. Increasing pesticide and fertilizer application, willingness and use by farmers has a positive impact on food supply and a negative impact on habitat quality. An increase in the number and willingness of farmers participating in restoring farmland to forests and water conservancy projects was observed. This has a positive impact on soil conservation, water production, and carbon sequestration. Among them, the application of chemical fertilizers and pesticides has the most significant impact on food supply and habitat support, and the willingness to implement the projects on restoring farmlands to forests has the most significant impact on carbon sequestration. The willingness to implement terracing has the greatest impact on water production and soil conservation, and aesthetic value has the greatest impact on cultural services.

Delimiting Ecological Space and Simulating Spatial-Temporal Changes in Its Ecosystem Service Functions Based on a Dynamic Perspective: A Case Study on Qionglai City of Sichuan Province, China

Delimiting ecological space scientifically and making reasonable predictions of the spatial-temporal trend of changes in the dominant ecosystem service functions (ESFs) are the basis of constructing an ecological protection pattern of territorial space, which has important theoretical significance and application value. At present, most research on the identification, functional partitioning and pattern reconstruction of ecological space refers to the current ESFs and their structural information, which ignores the spatial-temporal dynamic nature of the comprehensive and dominant ESFs, and does not seriously consider the change simulation in the dominant ESFs of the future ecological space. This affects the rationality of constructing an ecological space protection pattern to some extent. In this study, we propose an ecological space delimitation method based on the dynamic change characteristics of the ESFs, realize the identification of the ecological space range in Qionglai City and solve the problem of ignoring the spatial-temporal changes of ESFs in current research. On this basis, we also apply the Markov-CA model to integrate the spatial-temporal change characteristics of the dominant ESFs, successfully realize the simulation of the spatial-temporal changes in the dominant ESFs in Qionglai City's ecological space in 2025, find a suitable method for simulating ecological spatial-temporal changes and also provide a basis for constructing a reasonable ecological space protection pattern. This study finds that the comprehensive quantity of ESF and its annual rate of change in Qionglai City show obvious dynamics, which confirms the necessity of considering the dynamic characteristics of ESFs when identifying ecological space. The areas of ecological space in Qionglai city represent 98307 ha by using the ecological space identification method proposed in this study, which is consistent with the ecological spatial distribution in the local ecological civilization construction plan. This confirms the reliability of the ecological space identification method based on the dynamic characteristics of the ESFs. The results also show that the dominant ESFs in Qionglai City represented strong non-stationary characteristics during 2003–2019, which showed that we should fully consider the influence of the dynamics in the dominant ESFs on the future ESF pattern during the process of constructing the ecological spatial protection pattern. The Markov-CA model realized the simulation of spatial-temporal changes in the dominant ESFs with a high precision Kappa coefficient of above 0.95, which illustrated the feasibility of using this model to simulate the future dominant ESF spatial pattern. The simulation results showed that the dominant ESFs in Qionglai will still undergo mutual conversions during 2019–2025 due to the effect of the their non-stationary nature. The ecological space will still maintain the three dominant ESFs of primary product production, climate regulation and hydrological regulation in 2025, but their areas will change to 32793 ha, 52490 ha and 13024 ha, respectively. This study can serve as a scientific reference for the delimitation of the ecological conservation redline, ecological function regionalization and the construction of an ecological spatial protection pattern.

Additive Allometric Equations to Improve Aboveground Biomass Estimation for Mongolian Pine Plantations in Mu Us Sandy Land, Inner Mongolia, China

Afforestation is conducive to improving ecosystem service functions and ecosystem diversity in the Mu Us Sandy Land, however, the important attribute of biomass for Mongolian pine (Pinus sylvestris var. mongolica Litv.) plantations has yet to be accurately evaluated. This study aimed to develop additive allometric biomass equations for the species and evaluate biomass partitioning patterns within tree components. A total of 131 trees were measured for stem, branch, and leaf biomass by destructively sampling and tree climbing, with the latter as a supplement. For each biomass component, we tested three equations with the diameter at breast (D) alone, height (H) as additional, and diameter in combination with height (D2H) as predictors using the weighted least squared method. Weighted nonlinear seemingly unrelated regression was adopted to fit a system of additive allometric biomass equations utilizing the selected equations. A leave-one-out cross-validation method (the jackknife procedure) was used to assess the predictive ability. The biomass partitioning pattern was evaluated by calculating the ratios. The results revealed that the diameter alone is a good predictor for branches and foliage biomass estimates, while the stem requires H included to improve estimation accuracy. Mongolian pine allocates relatively more biomass to the crown (51.4%) compared to the stem (48.6%). Branch biomass fraction increased monotonously with increasing tree size while a reverse trend was observed for foliage. In conclusion, the additive models developed in this study provide a robust biomass estimation and can be extensively used to estimate Mongolian pine forests biomass in Mu Us Sandy Land.

Vegetation Productivity and Precipitation Use Efficiency across the Yellow River Basin: Spatial Patterns and Controls

In arid and semi-arid climate zones, understanding the spatial patterns and biogeographical mechanisms of net primary production (NPP) and precipitation use efficiency (PUE) is crucial for assessing the function and stability of ecosystem services, as well as directing ecological restoration. Although the vegetation coverage has changed dramatically after the construction of several ecological restoration projects, due to limited observation data, fewer studies have provided a thorough understanding of NPP and PUE’s recent spatial patterns and the controlling factors of different vegetation types in the Yellow River Basin (YRB). To narrow this gap, we integrated remote-sensing land-cover maps with long-term MODIS NPP and meteorological datasets to comprehend NPP and PUE spatial patterns in YRB. Furthermore, we applied structural equation models (SEM) to estimate the effect intensity of NPP and PUE controlling factors. The results showed that along geographical coordinates NPP and PUE decreased from southeast to northwest and trends were roughly consistent along latitude, longitude, and elevation gradients with segmented patterns of increasing and decreasing trends. As for climate gradients, NPP showed significant linear positive and negative trends across the mean annual precipitation (MAP) and the arid index (AI), while segmented changes for PUE. However, the mean annual average temperature (MAT) showed a positive slope for below zero temperature and no change above zero temperature for both NPP and PUE. SEM results suggested that AI determined the spatial pattern of NPP, whereas PUE was controlled by MAP and NPP. As the AI becomes higher in the further, vegetation tends to have decreased NPP with higher sensitivity to water availability. While artificial vegetation had a substantially lower NPP than original vegetation but increased water competition between the ecosystem and human society. Hence further optimization of artificial vegetation is needed to satisfy both ecological and economic needs. This study advanced our understanding of spatial patterns and biogeographic mechanisms of NPP and PUE at YRB, therefore giving theoretical guidance for ecological restoration and ecosystem function evaluation in the face of further climate change.

Effect of Revegetation in Extremely Degraded Grassland on Carbon Density in Alpine Permafrost Regions

Revegetation has been proposed as an effective approach to restoring the extremely degraded grassland in the Qinghai–Tibetan Plateau (QTP). However, little is known about the effect of revegetation on ecosystem carbon density (ECD), especially in alpine permafrost regions. We compared aboveground biomass carbon density (ABCD), belowground biomass carbon density (BBCD), soil organic carbon density (SOCD), and ECD in intact alpine meadow, extremely degraded, and revegetated grasslands, as well as their influencing factors. Our results indicated that (1) ABCD, BBCD, SOCD, and ECD were significantly lower in extremely degraded grassland than in intact alpine meadow; (2) ABCD, SOCD, and ECD in revegetated grassland significantly increased by 93.46%, 16.88%, and 19.22%, respectively; (3) stepwise regression indicated that BBCD was mainly influenced by soil special gravity, and SOCD and ECD were controlled by freeze–thaw strength and soil temperature, respectively. This study provides a comprehensive survey of ECD and basic data for assessing ecosystem service functions in revegetated grassland of the alpine permafrost regions in the QTP.

Coupled regulatory mechanisms and synergy/trade-off strategies of human activity and climate change on ecosystem service value in the loess hilly fragile region of northern Shaanxi, China

• The interannual ecosystem service value (ESV) increased slowly, and its geographical distribution fluctuated in a non-stationary pattern. • Significant value transformations existed among ecosystem service types and among land use types. • ESV was primarily positively governed by annual precipitation extremely negatively regulated by the synergistic effect of land use degree and population density. • The values of regulating, supporting, and cultural services interacted synergistically in significant ways. Geographic and temporal patterns of ecosystem service value (ESV) and their dynamic coupling response to human activity and climate change are critical for allocating land resources and maintaining healthy ecosystems in the loess hills. Based on five phases of land use data and climate data in Yan'an from 2000 to 2020, our study utilized the value-equivalent method and statistical analysis to systematically reveal the spatio-temporal dynamics of human activity and climate change, as well as their coupled driving mechanisms on ESV, and to establish and optimize synergy/trade-off strategies between them. The findings revealed that land use degree diminished between 2000 and 2020, population distribution increasingly widened. The precipitation fluctuated and increased, but the dryness trend persisted. Significant contributions were made by regulating services, supporting services, grassland, and forest to the interannual total ESV, which grew steadily at a rate of 6.89 % and reached 722.59 trillion in 2020. The total geographical distribution pattern of ESV was unstable, with a medium level of aggregation (0.02–0.06 trillion) in the northern districts and counties and a high level of aggregation (0.06–0.08 trillion) in the southwest and southeast on the grid scale of 1 km × 1 km. ESV had a highly significant synergistic relationship with annual precipitation (AP), but it showed pronounced trade-offs with population density (PD), comprehensive index of land use degree (LUI) and annual mean surface temperature (AMT). Simultaneously, there were profound synergies between the value of regulating, supporting, and cultural services. ESV was primarily positively governed by AP extremely negatively regulated by the synergistic effect of LUI and PD, the optimal regulatory thresholds of LUI, PD and AP for ESV levels of ≥0.06 trillion on the grid scale of 1 km × 1 km were 260, 30,000–50,000 people km −2 , and 400–520 mm, respectively. Essentially, controlling the land use degree, expanding farmland and water areas, and stimulating climate humidification were crucial synergistic/trade-off strategies for further balancing and enhancing the value of various ecosystem service functions in sustainable ecological restoration of Yan'an.

Land use trade-offs and synergies based on temporal and spatial patterns of ecosystem services in South China

• Analysis of ESV and relationships provide new insight into land use policies. • Influencing factors make obvious effects on ESV spatial distribution. • Regulatory services are synergy with supply service in South China. • ESVs in 2035 are increased by sustainability development scenario. • Four ecological function zones contribute to the industrial configuration. A clear understanding the relation between ecological protection and economic development provides new insight into land use policies. Land use trade-offs and synergies based on ecosystem service value (ESV) is important to regional sustainable development. In this study, we took the South China as an example, assessed the spatial and temporal changes of ecosystem service function over 20 years, and proposed a land use planning in 2035 by socio-ecological constraints and multiyear land use observations. The results showed that ESV acts a downward trend from 2000 to 2020. ESV of water conservation, soil retention, carbon sequestration, and habit quality showed a synergistic relationship with products supply. After the trade-offs and synergies of land use, the ESV in 2035 significantly improved compared with that in 2020. Finally, we proposed 4 ecological function zones land use strategy by considering trade-offs and synergies of ecological protection and economic development in studying areas to regulate the industrial configuration. This planning strategy will maintain steadily increasing of ecosystem service function until 2035, and meantime guarantee the regional ecological security.

Effects of Two Management Practices on Monthly Litterfall in a Cypress Plantation

Optimizing stand structure can enhance plantation forest ecosystem service functions by regulating litterfall patterns; however, the effects of close-to-nature management on litterfall production remain unclear. Here, we selected three cypress (Cupressus funebris) plantations, including one using the practice of strip filling (SF), one using the practice of ecological thinning (ET), and one pure cypress plantation without any artificial interference. The production of total litterfall and its components (leaf, twig, reproductive organ and miscellaneous litterfall) were investigated monthly over one year from September 2019 to August 2020. Compared with that of the pure plantation, the total annual litterfall production of the SF and ET plantations decreased significantly by 10.8% and 36.44%, respectively. The annual production of leaf and reproductive organ litter was similar to that of total litterfall, but that of twig and miscellaneous litter was higher in the SF and ET plantations than in the pure plantation. Moreover, total, leaf and reproductive organ litterfall production displayed unimodal dynamics regardless of plantation, although the peaks of reproductive organ litter production occurred in different months. In contrast, the production of twig litter showed bimodal dynamics in the pure plantation, while unimodal and irregular dynamics were observed in the plantations with ET and SF, respectively. Additionally, insignificant differences in the isometric growth index of leaf litter and total litterfall were observed. The allometric indices of twig litterfall versus total litterfall, reproductive organ litterfall versus total litterfall, and leaf litterfall versus twig litterfall were higher in the plantations with SF and ET than in the pure plantation. Redundancy analysis (RDA) revealed that diameter at breast height and air temperature were the most important factors shaping the annual and monthly production of litterfall, respectively. These results provide efficient data to support the rectification of the material circulation of cypress plantations and their future management.

Evaluation of Cultural Ecosystem Service Functions in National Parks from the Perspective of Benefits of Community Residents

The ecosystem of national parks bears some cultural features. How the cultural ecosystem service functions are perceived by the public and how the cultural ecosystem service functions shape the public’s cognition have become urgent scientific questions. This paper performs a case analysis on the Qianjiangyuan National Park System Pilot Area, a representative national park in China, which clarifies the main types of cultural ecosystem service functions from the perspective of the landscape aesthetics benefits of community residents, and analyze the varied impacts of demographics on functional cognition. On this basis, the entropy weight method was adopted to evaluate the importance of each function. Fuzzy comprehensive evaluation was employed to assess the composite level of the cultural service functions. The results show that: (1) the community residents value the benefits brought by the national park the most in terms of the ecological improvement function, and the situation is consistent across the four towns/townships; by contrast, the community residents attach the least importance to the benefits in terms of system governance function. (2) Except for the years of local residence, the community residents’ cognition of different cultural ecosystem service functions may vary significantly, owing to factors like gender, age, education level, occupation, and annual mean income. (3) Concerning the importance of functional indices, the importance scores of the natural experience functions, humanistic concern functions, and social service functions are 0.3286, 0.3503, and 0.3211, respectively. The community residents had a moderate to high level of cognition for the cultural ecosystem service functions (3.99). The different types of functions can be sorted by effectiveness as: the social service functions (4.11) > natural experience functions (4.03) > humanistic concern functions (3.86). The research results provide a reference for improving the management level of national parks, and ease the increasingly prominent contradiction between people and land.

Assessment of Ecological Cumulative Effect due to Mining Disturbance Using Google Earth Engine

Open-pit mining and reclamation damage the land, resulting in unknown and significant changes to the regional ecology and ecosystem services. Surface mining restoration procedures necessitate a significant amount of money, typically at an unclear cost. Due to temporal and regional variability, few studies have focused on the cumulative impacts of mining activities. To investigate the ecological cumulative effects (ECE) of past mining and reclamation activities, this study continuously tracked land cover changes spatially and temporally based on phenological indices and focuses on the spatial and temporal evolution of past mining and reclamation areas using the LandTrendr algorithm. The cumulative trends of ecosystem services in the Pingshuo mining area from 1986 to 2021 were revealed using a uniform standard value equivalent coefficient. Meanwhile, the cumulative ecological effects due to essential ecosystem service functions were analyzed, including soil formation and protection, water containment, biodiversity maintenance, climate regulation, and food production. The synergistic effects and trade-offs among the functions were also explored using Spearman’s correlation coefficient. The results showed that (1) open-pit mining resulted in 93.51 km2 of natural land, 39.60 km2 of disturbed land, and 44.58 km2 of reclaimed land in the Pingshuo mine; (2) open-pit mining in the mine mainly resulted in the loss of 122.18 km2 (80.91%) of native grassland, but, through reclamation into grassland (31.30 km2), cropland (72.95 km2), and forest land (10.62 km2), the damaged area caused by mining only slightly increased; (3) the cumulative ecological value of the mining area declined by 128.78 million RMB; however, the real cumulative value per unit area was lower in the disturbance area (1483.47 million RMB) and the reclamation area (1297.00 million RMB) than in the natural area (2120.98 million RMB); (4) the cumulative value of the food production function in the study area increased, although the values of all individual functions in the study area decreased. Most of the cumulative values of services had a strong synergistic relationship. However, in the natural area, food production (FP) showed a trade-off relationship with the cumulative value of biodiversity maintenance (BM), soil formation and protection (SP), and water conservation (WC) service functions, respectively. This study constructed a methodology for analyzing mining-impacted ecosystem services using time-series processes, reproducing historically complete information for policymakers and environmental regulators.