Evolution characteristics and meteorological impacts of ecosystem regulation service functions in Jiangxi Province, China from 2000 to 2022.

Research on forest ecosystem service (ES) assessments is currently a topic of much interest in forest ecology combined with geography. Forests are the mainstay of terrestrial ecosystems and provide a wide range of welfare supports for humans. Pinus massoniana (PM) Lamb. is a major silvicultural timber species in southern China and plays an important role in meeting domestic timber demand as well as providing ESs. The assessment of the ESs of PM plantation forests is beneficial for their sustainable management. In this study, we used the woody biomass method, the InVEST water content model and the USLE, a generalized soil loss equation model to assess the values of four Ess, including wood supply, carbon sequestration and oxygen release, water conservation, and soil conservation, in PM plantations in the Guangxi Paiyangshan Forest Farm, which is a national PM seed base. A spectral clustering method was used to identify the ecosystem service clusters (i.e., partitions) in the case study area, and certain strategies were provided for different partitions to form a management strategy for the sustainable management of PM plantation forest ecosystems. This study showed that the value of each ES per hectare in the northern tropical pine plantation, ranked from the largest to the smallest, was water conservation; carbon sequestration and oxygen release; wood supply; and soil conservation, with the values of the wood supply in addition to carbon sequestration and oxygen release per hectare increasing with the age of the plantation. Based on the different service characteristics within the service clusters, the northern tropical PM plantation area was divided into wood supply, ecological nourishment and ecological restoration areas, which can focus more on wood supply and ecological nourishment.

To assess the ecosystem services value of forests for snail control and schistosomiasis prevention in the Yangtze River Basin, The Benefit Of Forestry Schistosomiasis Prevention Ecological Project, referenced as Specifications for Assessment of Forest Ecosystem Services in China (LY/T 1721-2008), was evaluated scientifically by market value method and shadow engineering method selecting water conservation, soil conservation, carbon sequestration, oxygen released, biodiversity conservation, snail control and schistosomiasis prevention to value ecosystem services. Results showed that ecosystem service ecological benefit of forests for snail control and schistosomiasis prevention in the Yangtze River Basin was great from 2006-2013 with water conservation totaling 16.16×108 tons, soil conservation 1.46×108 tons, carbon sequestration 0.10×108 tons, oxygen released 0.29×108 tons, snail area decreasing 24.35×107 square meters, and the number of schistosomiasis patients decreasing by 613.1 thousand. This was a saving of about 967.20×108 Yuan in all. Snail control and schistosomiasis prevention had the greatest value accounting for 35.87%, oxygen release accounted for 33.06%, carbon sequestration accounted for 13.02%, water conservation accounted for 9.17%, soil conservation accounted for 7.31%, and biodiversity conservation had the least value, accounting for 1.57%. The ecosystem services value for different provinces was Hunan > Hubei > Jiangxi > Anhui > Jiangsu > Sichuan > Yunnan. Of the seven provinces, snail control and schistosomiasis prevention of Anhui Province was greatest accounting for 18.17%. The other five function values were largest in Hunan Province. The study found that the comprehensive ecosystem service of snail prevention and control, oxygen release, carbon sequestration, water conservation, and soil conservation accounted for 98.43% of the ecosystem service value. The government of Hunan Province attached great importance to the prevention and treatment of schistosomiasis and undertook suppressing snail work the most. In hilly regions of Yunnan Province, Oncomelania Snail has a variety of environment, and its vitality is strong and its reproduction is fast, the difficulty of the prevention and control of schistosomiasis is relatively large, and the benefit of the snail suppression is not significant. This study provided a scientific basis for understanding the ecological role of snail prevention and control.

Over the past 40 years of reform and opening up, human activities in the Yangtze River Delta region have caused major changes in land use patterns and ecosystem functions. Clarifying the spatiotemporal change characteristics and future development trends of ecosystem service functions is the basis for rational land development and utilization. In this study, the InVEST model and the CASA model were used to calculate habitat quality, water conservation, carbon sequestration and oxygen release, and soil conservation ecosystem services in the Yangtze River Delta urban agglomeration from 1980 to 2020. The spatial pattern, change law, and future trend of these services were analyzed using the Theil–Sen median trend analysis, Mann–Kendall test, and Hurst index analysis. The results show that the four types of ecosystems in the Yangtze River Delta urban agglomeration (habitat quality, water conservation, carbon sequestration and oxygen release, and soil conservation) exhibited an overall spatial pattern of being high in the southwest mountainous area and low in the northeast plain, and the conversion from constructed to agriculture was the most frequent type of land conversion over the past 40 years. From 1980 to 2020, the average level of habitat quality showed a downward trend and is expected to continue to deteriorate in the future. Water conservation, carbon sequestration and oxygen release, and soil conservation showed a fluctuating upward trend, with the latter two primarily predicted to have a future trend of improvement. The changes in ecosystem services exhibit gradient effects and horizontal spatial differentiation. The decline in ecosystem service functions is more pronounced in the vicinity of large cities. It is thus necessary to accelerate the transformation of the economic development model, and abandon the extensive urbanization development model, and promote high-quality urbanization development on the basis of improving resource and environmental carrying capacities.

Based on forest inventory data (FID) at sublot level, we estimated the carbon sequestration in forest vegetation of Beijing, China in 2009. In this study, the carbon sequestration in forest vegetation at sublot level was calculated based on net biomass production (ΔB) which was estimated with biomass of each sublot and function relationships between ΔB and biomass. The biomass of forested land was calculated with biomass expansion factors (BEFs) method, while those of shrub land and other forest land types were estimated with biomass, coverage and height of referred shrubs and shrub coverage and height of each sublot. As one of special forested land types, the biomass of economic tree land was calculated with biomass per tree and tree number. The variation of carbon sequestration in forest vegetation with altitude, species and stand age was also investigated in this study. The results indicate that the carbon sequestration in forest vegetation in Beijing is 4.12 × 106 tC/yr, with the average rate of 3.94 tC/(ha·yr). About 56.91% of the total carbon sequestration in forest vegetation is supported by the forest in the plain with an altitude of < 60 m and the low mountainous areas with an altitude from 400 m to 800 m. The carbon sequestration rate in forest vegetation is the highest in the plain area with an altitude of < 60 m and decreased significantly in the transitional area from the low plain to the low mountainous area with an altitude ranging from 200 m to 400 m due to intensive human disturbance. The carbon sequestration of Populus spp. forest and Quercus spp. forest are relatively higher than those of other plant species, accounting for 25.33% of the total. The carbon sequestration in vegetation by the forest of < 40 years amounts to 45.38% of the total. The carbon sequestration rate in forest vegetation peaks at the stand age of 30–40 years. Therefore, it would be crucial for enhancing the capability of carbon sequestration in forest vegetation to protect the forest in Beijing, to limit human disturbance in the transitional area from the plain to the low mountain area, and to foster the newly established open forest.

The configuration of plants of soil and water conservation resources is an important “source” and “sink” of ecological construction. Plants of soil and water conservation are of great significance for the control of soil erosion. However, in the practice of comprehensive management of soil and water conservation in Jiangxi Province, the selection range of plant resources for soil and water conservation is limited, and the plant varieties are not abundant. Therefore, it is one of the important ways to enrich the resource base of plants of soil and water conservation and improve the ecological environment of red erosion area in Jiangxi Province to screen out plants of soil and water conservation and corresponding configuration models with development value for Jiangxi Province and evaluate the benefits of plants of soil and water conservation configuration model in typical project areas.

Based on the Forest Ecosystem Services Assessment Standards (LY/T 1721－2008) issued by the State Forestry Administration, this paper evaluated four key functions of forest ecosystems, i.e., water conservation, soil conservation, carbon fixation and oxygen release, and nutrient accumulation. Focusing on the project area of Majiang County in Guizhou Province, this study provided some quantitative evidence that the implementation of the small hydropower substituting fuel project had positive effects on the values and material quantities of ecosystem service functions. The results showed that the small hydropower substituting fuel project had a significant effect on the increase of forest ecosystem services. Water conservation quantity of Pinus massoniana and Cupressus funebris plantations inside project area was 20662.04 m3·hm-2·a-1, 20.5% higher than outside project area, with soil conservation quantity of 119.1 t·hm-2·a-1, 29.7% higher than outside project area, carbon fixation and oxygen release of 220.49 t·hm-2·a-1, 40.2% higher than outside project area, and forest tree nutrition accumulation of 3.49 t·hm-2·a-1, 48.5% higher than outside project area. Small hydropower substituting fuel project for increasing the quota of forest ecosystem service function value was in the order of carbon fixation and oxygen release function (71400 yuan·hm-2·a-1) > water conservation function (60100 yuan·hm-2·a-1) > tree nutrition accumulation function (13800 yuan·hm-2·a-1) > soil conservation function (8100 yuan·hm-2·a-1). Small hydropower substituting fuel project played an important role for improving the forest ecological service function value and realizing the sustainable development of forest.

The carbon sequestration and oxygen release of landscape plants are dominant ecological service functions, which can play an important role in reducing greenhouse gases, improving the urban heat island effect and achieving carbon peaking and carbon neutrality. In the present study, we are choosing Lonicera japonica Thunb. as a model plant to show the effects of Cd stress on growth, photosynthesis, carbon sequestration and oxygen release characteristics. Under 5 mg kg−1 of Cd treatment, the dry weight of roots and shoots biomass and the net photosynthetic rate (PN) in L. japonica had a significant increase, and with the increase in Cd treatment concentration, the dry weight of roots and shoots biomass and PN in the plant began to decrease. When the Cd treatment concentration was up to 125 mg kg−1, the dry weight of root and shoots biomass and PN in the plant decreased by 5.29%, 1.94% and 2.06%, and they had no significant decrease compared with the control, indicating that the plant still had a good ability for growth and photoenergy utilization even under high concentrations of Cd stress. The carbon sequestration and oxygen release functions in terms of diurnal assimilation amounts (P), carbon sequestration per unit leaf area (WCO2), oxygen release per unit leaf area (WO2), carbon sequestration per unit land area (PCO2) and oxygen release per unit land area (PO2) in L. japonica had a similar change trend with the photosynthesis responses under different concentrations of Cd treatments, which indicated that L. japonica as a landscaping Cd-hyperaccumulator, has a good ability for carbon sequestration and oxygen release even under high concentrations of Cd stress. The present study will provide a useful guideline for effectively developing the ecological service functions of landscaping hyperaccumulators under urban Cd-contaminated environment.

The data of valuation of forest ecosystem service function (FESF) in 101 primary case studies of China were collected and obtained based on Specifications for Assessment of Forest Ecosystem Services in China (LY/T 1721-2008). FESF was then analyzed synthetically in terms of value coefficient. The results showed that the average value per unit area (VPUA) of FESF in China was 6.11×104 yuan·hm-2, and the order of VPUA of each service function was: water conservation (2.44×104 yuan·hm-2)> soil conservation (1.15×104 yuan·hm-2)> biodiversity conservation (1.00×104 yuan·hm-2)> carbon fixation and oxygen release (0.98×104 yuan·hm-2)> atmosphere environmental purification (0.28×104 yuan·hm-2)> forest recreation (0.23×104 yuan·hm-2)> action of forest against natural calamities (0.19×104 yuan·hm-2)> nutrient accumulation(0.16×104 yuan·hm-2). Water conservation, soil conservation, biodiversity conservation, carbon fixation and oxygen release were the four dominant service functions of forest ecosystem in China. The VPUA of FESF of the reserve level was higher than that of county level. The establishment of reserves played positive roles in biodiversity conservation and enhancement of service function, but the service function of forest recreation still existed with some insufficiency, and it needed to be further improved. Dominant service functions of forest ecosystem varied in different physicographic regions, and each type of service function presented different differentiation characteristics in space. The VPUA of FESF in South China was the highest up to 11.36×104 yuan·hm-2. The power regression correlation coefficients (R2) of the total value of FESF with forest area and forest stock volume were 0.905 (P<0.01) and 0.860 (P<0.01), respectively, indicating that forest area and forest stock volume were the two key factors affecting FESF and its total value. Moreover, latitude and mean annual precipitation also had significant effect on the VPUA of FESF.

北京市自然保护地生态效益及其影响因素

Dingxi City is located in the upper reaches of the Yellow River Basin, at the intersection between the Loess Plateau and West Qinling Mountains. The water and soil conservation function of Dingxi City is very important and have become key constraining factors for economic and social development. Due to the fragmented terrain and landscape patches, high spatial accuracy in the assessment of water and soil conservation is required for proper management. In this study, we introduced an index system for the evaluation of soil and water conservation functions, including various influencing factors. The results showed that area percentages of the five levels (lower, low, medium, high, and higher) in soil conservation were 6.24, 6.25, 23.49, 30.95, and 33.07, respectively, and the areas with higher soil conservation were mainly concentrated in the hilly and gully areas of the Loess Plateau with low vegetation coverage. The percentages of water conservation in the five levels (lower, low, medium, high, and higher) were 40.49, 21.78, 16.66, 7.9, and 13.11, respectively, and the areas with higher water conservation were concentrated in Min County and Zhang County, with the most abundant precipitation and highest vegetation coverage. In addition, functional areas of soil and water conservation had obvious spatial heterogeneity. Among them, the proportion of high-grade functional areas for soil conservation decreased with an increase in precipitation, whereas a high proportion of high-grade functional areas for water conservation was concentrated in areas with precipitation of more than 600 mm. The conflict between agricultural production and ecological protection of soil and water conservation is prominent, and areas with serious conflict are concentrated in the central and northern areas of Dingxi City. Based on this, we suggest a spatial layout guidance for agricultural production and ecological protection, providing a scientific basis for decision-making that supports ecological protection and high-quality sustainable development in Dingxi City.

Cultivated land horizontal ecological compensation is an essential means of reconciling agricultural ecosystem protection and regional economic development. It is important to design a horizontal ecological compensation standard for cultivated land. Unfortunately, there are some defects in the existing quantitative assessments of horizontal cultivated land ecological compensation. In order to raise the accuracy of ecological compensation amounts, this study established an improved ecological footprint model based on the ecosystem service function, focused on estimating the value of ecosystem service function, ecological footprint, ecological carrying capacity, ecological balance index and ecological compensation values of cultivated land in all cities of Jiangxi province. It then analyzed the rationality of ecological compensation amounts in Jiangxi province, which is one of the 13 provinces of major grain-producing areas in China. The results show the following: (1) The total value of soil conservation service function, carbon sequestration and oxygen release service function and ecosystem service function in Jiangxi province showed a spatial distribution trend of "gradually increasing around Poyang Lake Basin". (2) The cultivated land ecological deficit areas in Jiangxi province are Nanchang City, Jiujiang City and Pingxiang City; ecological surplus areas are Yichun City, Ji'an City and eight other cities; and there is an obvious "Spatial Agglomeration" phenomenon in ecological deficit and ecological surplus areas where ecological deficit areas are mainly concentrated in the northwest region of Jiangxi. (3) The amount needed to attain fair ecological compensation for cultivated land is 5.2 times the payment amount for cultivated land; this indicated there is larger arable land, a favorable condition for agricultural cultivation, and better supply capacity of ecosystem services in most of the cities of Jiangxi. (4) The compensation amount for cultivated land ecological surplus areas in Jiangxi province is generally higher than the cost of ecological protection, and its proportion in GDP, fiscal revenue and agriculture-related expenditure is significantly higher than that in ecological deficit areas; this indicated that the compensation value of cultivated land could play the driving role in the protective behavior for cultivated land. The results provide a theoretical and methodological reference for the construction of horizontal ecological compensation standards for cultivated land.

The vegetation for water and soil conservation on the Loess Plateau has resulted in the formation of large areas of low-quality and inefficient forests during its growth process, thereby hindering the high-quality development of such vegetation and compromising the sustainability of the ecological functions of soil and water conservation. This study focuses on Robinia pseudoacacia forests in the Caijiachuan watershed in the Loess region of western Shanxi. A comprehensive evaluation system for the ecological functions of soil and water conservation has been established to conduct a comprehensive assessment of the Robinia pseudoacacia forests. Additionally, the study identifies low-efficiency Robinia pseudoacacia forests and proposes reasonable regulation and control measures. The main research conclusions are as follows: (1) There are significant differences in the water and soil conservation functions among different Robinia pseudoacacia forests. The degree of inefficiency in these forests increases with forest density, and Robinia pseudoacacia forests with slopes between 35° and 40° are all low-efficiency forests. (2) The average density of high-efficiency Robinia pseudoacacia forests is 1655 trees per hectare, medium-efficiency forests average 1780 trees per hectare, and low-efficiency forests average 1927 trees per hectare. By substituting forest density, diameter at breast height (DBH), tree height, and crown width into the low-efficiency forest discrimination function, low-efficiency forests can be identified. The main influencing factors of low-efficiency forests are the Margalef richness index of shrubs, the total soil nitrogen content; and the nitrate nitrogen content. (3) Regulation measures for low-efficiency forests include controlling forest density to 1655 trees per hectare, increasing the richness of understory shrubs, and enhancing total soil nitrogen and nitrate nitrogen content by planting leguminous plants such as Lespedeza bicolor, Sophora davidii, and Vicia sepium. The research results can construct a comprehensive evaluation system for the ecological functions of Robinia pseudoacacia forests for water and soil conservation, identify low-efficiency forests, and provide precise regulation based on the causes of inefficiency, ensuring the sustainable function of Robinia pseudoacacia forests for water and soil conservation.

Since reform and opening, especially since entering the new century, economy in China has maintained a rapid and healthy development and more and more key hydraulic projects and hydropower stations have present the characteristics of rapid speed, short period and good benefits, but at the same time, they also have bought new challenges for soil and water conservation and ecological environment protection. In the late 1990s, China has instituted a set of laws and regulations on soil and water conservation and ecological environment protection to reinforce environment management in development and construction projects. We were implementing ecological environment construction engineering of soil and water conservation at the same time when the Three Gorges Hydraulic Project on the Yangtze River, Xiaolangdi and Wanjiazhai Hydraulic Projects on the Yellow River, Dachaoshan Hydraulic Project on Lancang River and other key hydraulic projects and hydropower stations were being constructed, and have achieved notable effects. The common characteristics of the soil and water conservation and ecological environment construction of the main key hydraulic projects are: First, making water and soil conservation plans and its special designs at the beginning of major project design. Second, implementing prevention-control measures of water and soil loss when the project was under construction. Third, accepting major project consisted of special acceptance of water and soil conservation engineering, performing the national requirements of the three-simultaneity system between the construction and development projects and the water and soil conservation very well.

Carbon sequestration by vegetation and soil conservation are vital components in balancing greenhouse gas emissions and enhancing terrestrial ecosystem carbon sinks. They also represent an efficient pathway towards achieving carbon neutrality objectives and addressing numerous environmental challenges arising from global warming. Soil and water conservation, as crucial elements of ecological civilisation development, constitute a key link in realising carbon neutrality. This study systematically quantifies and forecasts the spatiotemporal characteristics of carbon sink capacity in soil and water conservation within the study area of Puding County, a typical karst region in Guizhou Province, China. Following a research approach of “mechanism elucidation–model construction–categorised estimation”, we established a carbon sink calculation system based on the dual mechanisms of vertical biomass carbon fixation via vegetative measures and horizontal soil organic carbon (SOC) retention using engineering measures. This system combines forestry, grassland, and engineering, with the aim of quantifying regional carbon sinks. Machine learning regression algorithms such as Random Forest, ExtraTrees, CatBoost, and XGBoost are used for backtracking estimation and optimisation modelling of soil and water conservation as carbon sinks from 2010 to 2022. The results show that the total carbon sink capacity of soil and water conservation in Puding County in 2017 was 34.53 × 104 t, while the contribution of engineering measures was 22.37 × 104 t. The spatial distribution shows a pattern of “higher in the north and lower in the south”. There are concentration hotspots in the central and western regions. Model comparison demonstrates that the Random Forest and extreme gradient boosting regression models are the best models for plantations/grasslands and engineering measures, respectively. The LSTM model was applied to predict carbon sink variables over the next ten years (2025–2034), showing that the overall situation is relatively stable, with only slight local fluctuations. This study solves the problem of the lack of quantitative data on soil and water conservation as carbon sinks in karst areas and provides a scientific basis for regional ecological governance and carbon sink management. Our findings demonstrate the practical significance of promoting the realisation of the “double carbon” goal.

Response of hydrological ecosystem services to land-use change and risk assessment in Jiangxi Province, China