Ecosystem Service Function Research Articles

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.

Temporal and spatial differentiation characteristics of ecosystem service values based on the ecogeographical division of China: a case study in the Yellow River Basin, China.

The identification of spatiotemporal changes in ecosystem service values (ESVs) and their drivers is the basis for ecosystem service administration and decision-making. This research focuses on the Yellow River Basin (YRB). With a multitemporal land use and land cover (LULC) dataset (1995-2018), the equivalence coefficient method with spatiotemporal dynamic correction and exploratory spatial data analysis methods were used to evaluate ESV changes due to LULC changes and their spatial characteristics. The contributions of the ESV driving factors and their mutual effects were also investigated via geographic detectors. The results revealed that (1) the land use structure of the YRB, mainly grassland and cultivated land, was stable from 1995 to 2018. However, the transition between land use types was dramatic, including urban expansion accompanied by losses of farmland, grassland, and unused land; increased forestland; and significant increases in water bodies and wetland areas. (2) During the study period, the overall ESV of the YRB increased, and hydrological regulation and climate regulation services dominated the change in the ESVs in the study area. The ESV exhibited obvious ecogeographical pattern differentiation and evident positive spatial autocorrelation. High values were concentrated in the southern part of the study area, including the southeastern part of the Qinghai-Tibet Plateau region and the central part of the East Asian monsoon region. Low values were concentrated in the northwestern arid zone, dominated by desert and grassland ecosystems. (3) Because of the fragility of the regional ecological background, the spatial differentiation of the ESVs in the YRB is dependent on natural factors; however, anthropogenic factors such as the degree of land use and the human activity intensity also lead to ESV differentiation. The synergistic effects of human activities, landscape pattern changes, and natural factors result in the spatial differentiation of the ESVs in the research region. Therefore, human activities affecting the ecological environment should be controlled, nature-based solutions should be advocated, patch diversity should be increased, landscape fragmentation should be reduced, LULC ecosystem service functions should be improved, and the relationship among economic, social, and ecological landscape resources should be coordinated.

Spatio-Temporal Evolution and Driving Factors of Ecosystem Service Value of Urban Agglomeration in Central Yunnan

Urbanization and human activity have recently resulted in land use/cover change (LUCC), which has had a detrimental effect on the biological environment, on keeping the ecosystem’s sustainable growth and on comprehending the ecosystem’s quality and changes over the past 20 years in the central Yunnan urban agglomeration. The equivalent factor method and hotspot analysis were used to analyze the spatio-temporal changes in land use and ecosystem service value (ESV) in the urban agglomerations of central Yunnan province, and the effects of land use change on ESV were then examined. This study is based on the grid data of land use in 2000, 2005, 2010, 2015, and 2020. Finally, Geodetector was used to investigate the possible causes of ESV. The results showed that: (1) The urban agglomerations in central Yunnan’s land-use structure and pattern clearly changed between 2000 and 2020, with continual declines in grassland, cultivated land, and woodland, and constant increases in construction land. There was significant growth in both speed and area. (2) The average ESV of the land decreased consistently, the hotspot areas shrank, and the cold-spot areas grew as the ecosystem service function declined and the total amount of ESV decreased by 1.517 billion Yuan. These events were mostly explained by an increase in construction land and a decrease in grassland, cultivated land, and woodland. (3) The synergistic effect of numerous factors is what causes the change in ESV in the urban agglomerations of central Yunnan. The key forces behind ESV change in the research area were land-use intensity, normalized difference vegetation index (NDVI), slope, and people density. The results can help decision makers establish policies for ecological conservation and land use.

Ecosystem service trade-offs and identification of eco-optimal regions in urban agglomerations in arid regions of China

Ecosystems play an essential role in maintaining biodiversity, regulating climate, and promoting functional biodiversity in arid urban agglomerations. Accurately assessing the characteristics of ecosystem services and identifying eco-optimal regions in urban agglomerations in arid regions are important for ecological security and the sustainable development of regional ecological systems. In this study, the ecosystem service functions of Urban Agglomeration on the Northern Slope of the Tianshan Mountains (UANSTM) were evaluated using the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model based on the Geographic Information System (GIS) platform coupled with multi-source data. Moreover, the eco-optimal regions were identified by the Ordered Weighted Average (OWA). The findings demonstrate that the development and ecological construction of the UANSTM lead to the conversion of a large amount of unused land to grassland, cultivated land, and construction land. Analyzing the relationship between ecosystem services and land types shows that the high value ecosystem services are mainly distributed in forest land and grassland. In terms of changes in ecosystem services, the net primary productivity (NPP) and habitat quality (HQ) values increased, while the value of soil retention (SR) and water yield (WY) decreased. The relationship between ecosystem services is mainly pairwise synergy, except for HQ-WY and NPP-WY. Regarding spatial distribution, the trade-offs and synergies of ecosystem services demonstrated different geospatial heterogeneity. The OWA model was employed to establish different risk values and weights to simulate different risk scenarios. The area of coverage of risk scenario 5, with the highest trade-off values, was selected as the eco-optimal region. The eco-optimal regions were mainly located in the urban agglomeration's central and southwestern high-altitude areas, where a safety barrier was established for the ecological region. The results of this study can serve as a reference for the ecological construction, land planning, and management of urban agglomerations in arid regions.

Spatial evaluation of the ecological value importance of national park in Yarlung Tsangpo Grand Canyon

The Yarlung Tsangpo Grand Canyon (YTGC) region is one of China's vital gene banks of mountain biological species resources. It is also an experimental site for biologists worldwide to study how organisms differentiate in the exceptional environment of the plateau. Evaluating the importance of the ecological value and identifying extremely important regions to national parks to implement the strictest conservation is significant to protecting and preserving global biodiversity. YTGC as the study area, and a comprehensive evaluation model conformed to ecological value attributes was established: (i) evaluation of ecosystem service function, including water retention, soil and water conservation and biodiversity maintenance; (ii) evaluation of ecological vulnerability, including soil erosion and geological disasters; (iii) evaluation of ecological conservation, including Important Bird and Biodiversity Areas (IBAs), Global 200 Ecoregions (G200), Biodiversity Hotspots (BH), Endemic Bird Areas (EBAs) and Priority Areas for Biodiversity Conservation in China (PABCC). Identifying as extremely important, important, and general important regions, then mosaicked with the maximum value. The results show: first, the extremely important regions of ecosystem service are about 30,242.90 km2 (45.64%), distributed in most regions flowing southwest along the Yarlung Zangbo River. Second, the ecological vulnerability regions are about 26,561.65 km2 (40.06%), concentrated and contiguously distributed in the valley regions along the Yarlung Zangbo River and the high-altitude glacier-covered regions. Third, the extremely important regions for ecological conservation are mainly distributed in Milin County (39.86%) and Medog County (36.33%), which also presents a clustered distribution in the highly high mountains with apparent differentiation along the Yarlung Zangbo River valley in Milin County and the vertical natural belt centered on the Namjagbarwa and the Galabai Leifeng. Finally, we proposed that the integrated extremely important regions of ecological value should be divided into national parks for strict conservation; at the same time, it is also a reference for considering the construction of biodiversity conservation corridors when roads pass through the extremely important regions. This study presents a reliable and integrative method for effectively identifying conservation priority areas at small-medium scales, which can be applied to other PAs planning and management.

Driving factors of the variation of ecosystem service and the trade-off and synergistic relationships in typical karst basin

Since 2011, the Chinese government has been implementing a series of comprehensive rock desertification control projects. Concurrently, the relevant ecosystem service functions have been changing. However, few studies have quantitatively evaluated the variation of each ecosystem service function and its driving factors; moreover, the trade-off and synergistic relationships must be further explored. Therefore, the present study used a Soil and Water Assessment Tool (SWAT) model to stimulate three ecosystem service functions of the surface/underground runoff and surface sediment yield of Dabang River (a typical karst basin in Southwest China); the driving factors of ecosystem service variation were examined using geographic detectors; and a Spearman correlation analysis was performed to explore the trade-off and synergy between ecosystem services. This study revealed the following results: (1) The determination coefficient (R2) and Nash efficiency coefficient (NS) are>0.5 during the calibration and validation periods; therefore, they meet the model evaluation requirements, verifying the applicability of the SWAT model for ecological service function evaluation in karst areas. (2) Surface/underground runoff decreased by approximately 64% and 66.53% and surface sediment yield decreased by 25.89% in the study area from 2010 to 2018. (3) The geographic detector results revealed significantly higher explanatory power for two-factor detection than for single-factor detection for the variation of ecosystem services. Changes in various ecosystem services are closely related to rainfall reduction, land use changes, and the succession of rocky desertification. (4) Trade-off relationships exist between surface and underground runoff and between underground runoff and surface sediment yield; a synergistic relationship exists between surface runoff and surface sediment yield. The results provide a theoretical reference for the control of rocky desertification/soil erosion as well as for ecological protection and restoration work in karst areas of Southwest China.

A Study of Carbon Stock Changes in the Alpine Grassland Ecosystem of Zoigê, China, 2000–2020

Terrestrial carbon sequestration capacity is an important indicator of ecosystem service function, and the carbon storage value can reflect the climate regulation capacity of the regional ecological environment. The Zoigê alpine grassland is a representative area of the Qinghai-Tibet Plateau grassland ecosystem, with carbon sequestration types such as alpine grassland and marsh meadow and also an important water-conserving area in the upper reaches of the Yangtze River and the Yellow River. In this study, based on the land use/cover change pattern of the Zoigê alpine grassland region from 2000 to 2020, the carbon density coefficients corrected by the regional average annual precipitation and temperature factors were used to assess the carbon stocks of the Zoigê alpine grassland for three periods from 2000 to 2020 using the InVEST model. The results showed that the carbon stocks of the Zoigê alpine grassland region were 786.19 Tg, 780.02 Tg, and 775.22 Tg in 2000, 2010, and 2020, respectively, with a cumulative loss of 10.97 Tg and carbon densities of 183.70 t/ha, 182.26 t/ha, and 181.14 t/ha, showing a decreasing trend year by year. The carbon stock of the grassland ecosystem is the absolute contributor to the regional carbon stock, and the carbon stock accounts for 75.28% of the total carbon stock. The increase in the cultivated land area with a lower carbon density and the decrease in the grassland area with a higher carbon density are the main factors leading to the decrease in the carbon stock in the regional ecosystem of the Zoigê alpine grassland.

Analysis on the ecosystem service protection effect of national nature reserve in Qinghai-Tibetan Plateau from weight perspective

The analysis of the protection effect from the perspective of ecosystem service function (ESF) is an important basis for proposing optimal management strategies in nature reserves. Aiming at the internal, external, and different types of nature reserves of the National Nature Reserve in the Qinghai-Tibetan Plateau from 1992 to 2015, this study used the InVEST model to analyze the dynamic changes in four key ESFs, including carbon storage, water conservation, soil retention, and habitat quality. Based on this, the protective effect of nature reserves was evaluated. The main conclusions were as follows: (1) From 1992 to 2015, the spatial distribution pattern of carbon storage, water conservation, soil retention, and habitat quality inside and outside National Nature Reserve in Qinghai-Tibetan Plateau is “high in the east and decreasing to low in the west”. On the time scale, the stability inside the reserve was higher than that outside. (2) Among all types of nature reserves, the ESF of forest ecosystem nature reserves always ranked highest, and the ESF of desert ecosystem nature reserves ranked lowest. (3) During the 23-year period, the protection effect of ecosystem services inside National Nature Reserve was between 1.0821 and 1.0870, which was always higher than that of the outside areas. (4) The protection effect of the comprehensive ESF in forest ecosystem nature reserves ranked highest with a value of 1.3169. Although the protection effect of desert ecosystems is relatively weak, it has continuously increased from 0.8836 to 0.8955 over the 23-year period. Based on the changes in the ecological processes of nature reserves, exploring their protection effectiveness will help strengthen the comprehensive understanding of ecosystems in conservation research. The development of effective policies and management measures has had a positive effect on the adaptive adjustment of ecosystem service trade-offs.

Assessment of Changes in Key Ecosystem Factors and Water Conservation with Remote Sensing in the Zoige

As the largest alpine peat swamp wetland distribution area in the world, the Zoige has important ecological functions, including water conservation and biodiversity maintenance. In the past 20 years, the regional ecological protection and restoration measures continuously strengthened under the leadership of the local government have led to gradual improvements in the ecological environment of the region. In this study, multisource satellite remote-sensing image data were used to carry out quantitative monitoring and assessment of the main ecological elements (vegetation and water), as well as the regional leading ecosystem service function in the Zoige. Combined with local ecological protection management policies and measures, we analyzed the characteristics and effectiveness of ecological protection. We compared the ecosystem change trends of the Zoige reserve and the county, from 2001 to 2020, and found that the fractional vegetation cover (FVC) of Zoige county has increased at a rate of 0.25%/year. The growth rate was highest between 2015 and 2020, and the growth rate of FVC in the Zoige Wetland National Nature Reserve is approximately 1.89-fold that of the whole county. The water area also shows similar variation characteristics. On the whole, the water conservation capacity of the Zoige showed a significant increase from 2001 to 2020. We used high-resolution satellite remote-sensing images to capture the details of land use changes brought about by local ecological protection policies and measures, and together with macroecological indicators, we reflected on the effectiveness of regional ecological protection measures. We observed that the ecological effects of nature reserves are more direct and rapid, and the amount of water conservation within the nature reserve is about 1 × 104 m3/km2 higher than that of the surrounding grasslands. Satellite remote-sensing images can not only capture the multiscale change information of ecological indicators, such as vegetation and water, in a timely manner, but can also help us to identify the effectiveness of conservation measures by distinguishing and analyzing the causes of these changes.

Construction and Optimization of an Ecological Security Pattern Based on the MCR Model: A Case Study of the Minjiang River Basin in Eastern China

The Minjiang River Basin is one of the first pilot areas for ecological conservation and the restoration of mountain–river–forest–farmland–lake–grass in China. Taking the Minjiang River Basin as an example, this paper selected the importance of ecosystem service functions and ecological sensitivity to evaluate the ecological environment and identify ecological sources. Furthermore, we constructed an ecological resistance surface using artificial and natural interference factors. Through a minimum cumulative resistance model (MCR), the ecological security pattern (ESP) of “two barriers, one belt, many corridors, and many spots” was constructed. Research shows that: (1) In total, 43 ecological sources were identified, with a total area of 523 km2, accounting for 0.6% of the total land area. These were mainly distributed in the southwest and northwest of the Minjiang River Basin, such as in Zhangping, covered forest land, and cultivated land. (2) The connectivity of the network was low, and the spatial distribution of the ecological pinch points was uneven. A total of 118 ecological corridors and 22 important ecological pinch points were identified. The total length of the ecological corridor is 3,732,051.88 km, which is dense on the left side and sparse on the right side. (3) The ecological restoration area was composed of a low ecological safety area and a lower ecological safety area; the ecological control area was composed of a medium ecological safety area and a higher ecological safety area; and the ecological conservation area was composed of a high ecological safety area, at 6.5%, 27.7%, and 65.8%, respectively. Constructing the ESP of the Minjiang River Basin is important for promoting harmonious socioeconomic development and ecological protection. In addition, it can provide a reference basis for other experimental areas of mountain–river–forest–farmland–lake–grass.

Spatial-Temporal Characteristics of Ecosystem Service Values of Watershed and Ecological Compensation Scheme Considering Its Realization in Spatial Planning

A reasonable ecological compensation scheme for watersheds is beneficial for water resource protection and ecological sustainability. The existing literature has few watershed ecological compensation (WEC) schemes based on long-term observation and large spatial scale analysis of ecosystem service value (ESV) and considering its realization in spatial planning. Therefore, in order to establish a WEC scheme and integrate it into spatial planning, we take the Middle Route of South-to-North Water Diversion Project (MRSNWDP), a water resource area protecting the water resources at a huge local economic development cost, as a case study, and calculate the change trend and change range of the watershed’s total ESV from 1990 to 2015, thus, forming the WEC scheme. The results show the total ESV in the study area shows a slight downward fluctuation trend from 1990 to 2015, decreasing by 3310.70. The total ESV in most types of ecosystem service (ES) functions is relatively reduced except for the increase in functions of water conservation, waste treatment, and entertainment and culture. In addition, the change rate of total ESV has been in a high-value agglomeration, and the ES capabilities have been increasing since 2000, while the growth trend of the ES capabilities has been weak, and the high-value agglomeration has been expanding from the core area of Danjiangkou reservoir to the upstream and surrounding areas since 2005. We formulate a WEC scheme according to the partition idea of spatial planning that the priority compensation area accounts for 25.34% of the total study area, and the second priority compensation area, the general compensation area, and the potential compensation area account for 25.34%, 47.48%, and 12.80%, respectively.

Spatiotemporal evolution of sustainable utilization of water resources in the Yangtze River Economic Belt based on an integrated water ecological footprint model

Sustainable utilization of water resources (SUWR) is the basis of water resources management , allocation, and efficient utilization, which is crucial to promoting high-quality development and ensuring a region's water security. Appraising the sustainability of water resources and achieving a healthy regional water balance is a critical and complex problem. This study proposed an integrated water ecological footprint (IWEF) model that considered the water ecosystem service function and characteristics of human water consumption. The water ecological footprint, carrying capacity, water ecological pressure index ( EPI w ), ecological load index ( ELI w ), and eco-economic coordination index ( ECI w ) are developed to examine the level and degree of SUWR. The Yangtze River Economic Belt (YREB) is selected as the study area to comprehensively assess the spatiotemporal differentiation and dynamical evolution of SUWR. The results show that the EPI w and ELI w decreased by 50.27% and 64.29% in the YREB from 2011 to 2018, revealing the upward trend of SUWR. In terms of ECI w , the east part of the YREB experienced more strong decoupling states of water resources consumption and socio-economy. In the western part, the ecological safety state, sustainable development conditions of water resources, and the coordinated relationship of water pollution discharge toward economic growth are better than in the middle and eastern part of the YREB. This study helps to understand the complex interrelation between water and socio-economy at different spatial-temporal scales and provides a novel framework that can be used as an evaluation index and policy insights for the sustainability of water resources. • A novel framework is proposed to evaluate the sustainability of water resources. • The ecological footprint method is improved by considering water pollution factors. • Natural and socio-economic features are incorporated into the assessment model. • Assessing the sustainability of water resources in the Yangtze River Economic Belt. • Water sustainability is improving but the spatiotemporal differentiation is evident.

Evaluation and analysis of water conservation function of ecosystem in Shaanxi Province in China based on "Grain for Green" Projects.

The evaluation of water conservation function of the ecosystem and the analysis of influencing factors are conducive to the implementation of "Grain for Green" Projects, scientific management of land use types, and the optimization of ecosystem service functions. In this paper, we selected the data of precipitation, soil, evapotranspiration, land use/cover change, and other data to quantitatively evaluate the water conservation function of the ecosystem in Shaanxi Province from 1980 to 2015 and explored the key factors which lead to the spatial differences in water conservation functions. The results showed that (1) from 1980 to 2015, the water production and water conservation of Shaanxi Province's ecosystem based on grid units decreased by 12.81 × 108 m3 and 7.74 × 108 m3, respectively. (2) The use types of cultivated land, forest land, and grassland had a prominent contribution to the water production and water conservation of the ecosystem, while the contribution rate of water area, construction land, and unused land was small. During the research period, "Grain for Green" Projects consumed a lot of water production in a short period of time, which was not conducive to the improvement of water production capacity in Shaanxi Province. However, the conversion of cultivated land to grassland would help improve the water conservation capacity of the ecosystem, increasing the water conservation capacity by 0.77 × 108 m3. (3) The water conservation function of Shaanxi Province was "hot in the south and cold in the north," with obvious regional and spatial heterogeneity from 1980 to 2015. (4) The factors of precipitation, evapotranspiration, slope, common cultivated land area, afforestation area, and water conservation function showed a positive correlation, and the impact was significant, while the overall vegetation coverage index showed a negative correlation with it. Therefore, it is necessary to comprehensively consider the local climatic and environmental conditions to implement ecological protection and restoration policies in terms of enhancing water conservation function of the ecosystem. (5) Targeted measures are proposed for different areas in Shaanxi Province: The Northern Shaanxi area should be regarded as an ecological restoration and management area, focusing on returning farmland to grassland; Central Shaanxi Plain should be considered as an ecological protection zone, and the key task is to effectively protect the ecological land; the Southern Shaanxi area should be regarded as a key water conservation area, and the main function of the forest and grass ecosystem to conserve water is to be exerted.