Beijing-Tianjin Sandstorm Source Control Research Articles

Continuous Decline in Direct Incomes for Farmers Threatens the Sustainability of the Grain for Green Project

Understanding the impacts of ecological projects on household livelihoods is important in ensuring their sustainability. However, existing studies typically cover only a limited, discrete temporal point. Insufficient study duration makes it difficult to determine the full impact and dynamics of a project, affecting the veracity of the results. Representing one of the world’s largest investments in an ecosystem service programs, the Grain for Green Project (GGP) has an objective of increasing household incomes. Using data from 7112 questionnaires collected through 12 consecutive years (2007–2018) of field survey monitoring, this study examined the long-term impacts of the GGP on household livelihoods in the Beijing–Tianjin Sandstorm Source Control Project area through comparisons between participant households (PHs) and non-participant households (NPHs). The results show that GGP subsidies significantly increased household incomes only during the period 2007–2015, and their share of total household income decreased from 9.21% in 2007 to 1.62% in 2018. Subsidies for GGP cannot compensate farmers for losses due to the reduction in farmland. The above findings suggest that the effect of subsidies diminishes over time. Increased investment in jobs and skills training is needed to consolidate the GGP results. This provides new perspectives and empirical support for the study of international ecological compensation policies and sustainable development.

Identifying ecological governance zones for the Beijing-Tianjin Sandstorm Source Control Project by integrating ecosystem services and dust flow trajectories and its driving forces analysis

Achieving ecological conservation and governance based on ecosystem services (ESs) can balance regional ecological protection and development, which is of great significance for sustainable development. Existing research has mainly focused on the extraction of priority ecological conservation areas, thereby neglecting to consider the classification and management of ecological engineering areas. To improve regional ecological governance, we combine ESs and dust movement trajectory, using the Beijing-Tianjin Sandstorm Source Control Project (BTSSCP) as the research object to generate watersheds’ ecological governance zones. Six ESs were assessed to determine ecological zones. Trajectory simulation of dust movement, using the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model and potential source contribution function, was used to determined zones affected by dust. By combining these two aspects, five main ecological governance clusters were identified. We found that: (1) the area with low ESs in the northwest of the BTSSCP suffered from severe dust impacts; (2) slight dust-affected zones were mainly distributed in the eastern of the BTSSCP, and in the area, ESs gradually decreased from south to north; (3) ESs in the region was primarily influenced by natural factors and the influencing factors of ESs vary among different zones. These findings will not only contribute to the overall planning and governance of the BTSSCP, but can offer general guidance for the formulation of targeted ecological protection and restoration measures in other areas.

Exploring the combination and heterogeneity of ecosystem services bundles in the Beijing-Tianjin Sandstorm Source Control Project

The relationships among ecosystem services (ESs) and their spatiotemporal dynamics plays an essential role in ESs management. However, it is difficult to characterize the spatial composition of ecosystem services bundles (ESB), clarify the complex relationships and their driving forces. This study estimated 6 specific ESs of Beijing-Tianjin Sandstorm Source Control Project (BTSSCP) based on related models, using conjunction operations identified ESB, finally explored the trade-offs and synergies between ESs within each ESB, and furtherly suggested different management zones in terms of ESB types. The results indicated the values of all six key ESs have improved from 2000 to 2015, and shown a decreasing trend from the southeast to the northwest accompanied by expansion trend of the high value region. Additionally, ESB dominated by sand-fixing service were primarily distributed in the southwest and showed a trend of continuous and significant expansion from southwest to northeast during 2000–2015. And, wind speed, soil types, slope, vegetation types and population density are the main driving factors of ESB changes. What’s more, trade-offs and synergies among ESs appears the characteristics of spatial heterogeneity, especially between sand-fixing service and Net primary productivity, which presenting synergistic promotion relationship in bundles 1 and 2, while significant trade-offs in bundles 3 and 4. Finally, we divided BTSSCP into three zones—key improvement zone, ecological conservation zone, and integrated optimization zone based on ESB as per the regional sand-fixing capacity, enhancement potential and the relationship between ESs, and proposed specific suggestions for management in various ESB, which are beneficial to regional sustainable development and appropriate management.

Beijing-Tianjin sandstorm source control project helps the high-quality development of ecological construction

Beijing-Tianjin sandstorm source control project helps the high-quality development of ecological construction

Spatiotemporal Evolution of Soil Erosion and Its Driving Mechanism in the Mongolian Section of the Yellow River Basin

Soil erosion is a popular environmental issue that threatens sustainability. Influenced by multiple factors, such as climate, soil, and terrain, Baotou City, which is in the Bohai Sea Economic Circle and the Economic Belt along the Yellow River, has a severe ecological environment. In this study, revised soil and soil wind erosion equations were used to evaluate the soil erosion dynamics in Baotou City, and the potential driving factors of soil erosion were further investigated. Results showed that from 1990 to 2020, the water erosion modulus in Baotou City increased first, decreased, and then increased, with great fluctuations in annual changes. The wind erosion modulus decreased continuously, with a small fluctuation in annual changes. Water erosion in 2020 was more severe, with 4840.5 km2 added to the desert steppe and 1300.5 km2 reduced in the Yellow River Basin. The extent of wind erosion was significantly reduced, and the phenomenon of wind erosion improved. Meteorological factors are the primary factors that influence soil water erosion and soil wind erosion. Meanwhile, adverse climate changes can alter physical and chemical soil properties and vegetation coverage, thereby indirectly influencing soil erosion. With the implementation of the Beijing–Tianjin sandstorm source control, the farmland return to forest project, the ecological restoration and protection project at the southern and northern foothills of Daqingshan Mountains, grazing prohibition, and rotation grazing—including grassland awards, subsidies, and other policies and systems during this period—the overall deteriorating trend of the grassland ecological environment in Baotou was contained, grassland ecological system functions were improved, wind and sand erosion was prevented, biodiversity was maintained, and the ecological service functions of soil and water conservation were guaranteed.

Response of ecosystem services in Beijing-Tianjin Sandstorm Source Control Project to differing engineering measures scenarios

Changed land use patterns are the most direct manifestation of ecological engineering implemented by humans, being among the driving factors for changes in ecosystem services (ESs). However, different ecological engineering governance measures can lead to different changes in land use, resulting in corresponding changes to ESs and ecosystem service value (ESV), yet these changes is the content that needs to be clarified. In this study, four kinds of ESs, namely water yield, soil conservation, carbon storage and water purification, were quantified in part region of the Beijing-Tianjin Sandstorm Source Control Project (BTSSCP). In addition, eight scenarios were simulated according to the land use change caused by engineering management measures, and the ESs and ESV ensuing under these differing scenarios quantified accordingly. The results show that the main land use types in the study area from 2000 to 2020 were cropland and forestland, while during this period land use change mainly consisted of the expansion of grassland (+466.79 km2) and loss of cropland (−2095.27 km2). For different engineering management measures, protective governance will play a greater role in improving ESs than restoration governance. Protecting the existing governance outcomes from degrading can maintain a water yield of 36.85 × 108 m3, soil conservation of 73.72 × 106 t, carbon storage of 89.01 × 106 t, the purified water nitrogen content of 1.21 × 106 t, with the total ESV maintained at 54.237 billion yuan. Moreover, the high-investment counties clearly engage in ecological restoration that provides high ESV. Yet, there are still some counties with high project investment where the gains in ESV are low, such as Luanping county and Pingquan county. Therefore, it should be reasonably distributed based on the existing governance results in the next round of project investment allocation. In the past 20 years, engineering governance measures have significantly improved the ESs in the region. Nevertheless, looking ahead, it remains necessary to strengthen the emphasis on protecting governance outcomes.

Ecological restoration effects of the Beijing–Tianjin Sandstorm Source Control Project in China since 2000

The Beijing–Tianjin Sandstorm Source Control Project (BTSSCP) has been implemented for more than 20 years (2001–2022), and a scientific, accurate, and complete evaluation of its implementation effect is of great significance for the study of ecosystem evolution. In this study, we present a vegetation–water–soil–environment system comprising the net ecosystem productivity (NEP), water conservation (WC), soil erosion (SE), and habitat quality (HQ) to evaluate the spatiotemporal changes and future trends. The results showed that: (1) In areas with high vegetation coverage, only WC was significantly and negatively correlated with SE (−0.68, p less than 0.01). In areas with low vegetation coverage, NEP, WC, and HQ were all significantly negatively correlated with SE. This indicates that SE is a basic function that affects the performance of other ecological services. (2) From 2000 to 2020, the annual maximum average vegetation coverage increased by about 10 %; the annual average NEP increased by about 60 g C/km2, and the annual average SE decreased by about 500 t/km2. Compared with Phase I (2000–2010), the vegetation condition (coverage, NEP) in summer (July–August) was improved by about 10 %, and SE in winter (December–January) decreased by 3 t/km2 per month in Phase II (2010–2020). (3) In terms of future trends, NEP may continue to increase in the grassland area, especially in the Mu Us Sandland, but it may not change significantly in the forest area. Similarly, SE may continue to decrease in grassland-covered areas, but not in forest-covered areas. Most areas of WC could continue to increase, but the HQ will not change significantly. In general, the ecological restoration effects of the BTSSCP have improved significantly. This paper is intended to provide some key information for the management of ecological projects and regional ecological security.

The assessment of ecological restoration effects on Beijing-Tianjin Sandstorm Source Control Project area during 2000–2019

To halt the trend of desertification and improve the ecological environment in Beijing, Tianjin and surrounding areas, China establishes the ecological engineering of Beijing-Tianjin Sandstorm Source Control Project. The assessment of ecological restoration after the implementation of ecological engineering is conducive to the ensuing management of ecological engineering. Based on a large number of remote sensing data and calculation models, this study selected land use/cover, vegetation ecological quality indicators such as vegetation coverage and NPP, and other ecological service indicators such as water retention calculated by the InVEST model, soil retention by the RUSLE model, and sand fixing services by RWEQ model to comprehensively assess the degree of restoration and trend of ecological engineering implementation. The contributions of climate change and human activities to NPP and soil retention services are also assessed. We found that from 2000 to 2019, the land cover pattern is optimized, with desert and farmland turning to grassland and forest. The vegetation ecological quality has been improved, sand-fixing service have been significantly improved, and water retention and soil retention service are degraded in some areas. The areas with a high-degree restoration are mainly located in the water source protection areas in the Yanshan mountainous region and in some areas in the south-eastern Horqin Sandy Land, while the areas with a low-degree restoration are mainly located in the desert grassland. The ecological improvement areas are mainly distributed in the mountains in norther Shanxi Province, the water source protection area in the Yanshan mountainous region, the Southern Great Hinggnan Mountains and part of the agro-pastoral transitional grassland. The highly degraded areas are mainly concentrated in the middle of Horqin and Otindag Sandy Lands. Ecological engineering plays an important role in promoting ecological restoration by changing land use types. The contribution proportion of climate change to NPP and soil retention services are significantly higher than those of human activities. The degree of ecological restoration depends on the climax ecological background determined by the climate.

Dust amount reaching typical cities from dust emissions due to soil wind erosion in Beijing-Tianjin sandstorm source regions and its source analysis

<p indent="0mm">Dust emissions caused by soil wind erosion are a significant and concerning source of respirable particles in the atmospheric environment. Accurately estimating the contribution of dust emissions resulting from soil wind erosion to inhalable particulate matter in the urban atmospheric environment is required for the central government to formulate atmospheric environmental governance plans and decisions. By combining ground investigation, field observation, remote sensing image interpretation and other strategies, this paper first estimated the dust amount of four different particle sizes of 0–2.5, 2.5–5, 5–10, and <sc>10–20 μm</sc> arriving in Beijing, Zhangjiakou, Chifeng, Datong, Huhehaote, Xilinhaote, Baotou and Yulin, which derived from dust emissions caused by soil wind erosion due to wind force in Beijing-Tianjin sandstorm source regions. The total dust amounts reaching above cities were 274.49×10⁴, 146.96×10⁴, 151.83×10⁴, 91.03×10⁴, 68.61×10⁴, 65.42×10⁴, 41.46×10⁴, and <sc>26.21×10⁴ t,</sc> respectively. Among these dust amounts, PM_2.5 and PM₁₀ accounted for 35.40% and 84.16%, respectively. To improve the living environment, the Beijing-Tianjin sandstorm source control project targets both PM₁₀ and PM_2.5, with an emphasis on PM_2.5. Second, the contributions of subregions in the Beijing-Tianjin sandstorm source to dust amounts of different particle sizes for each city were distinctly different. For the contributions of each subregion to the total dust amount for above eight cities, the maximum came from the subregion of interlaced belt of agriculture and animal husbandry, followed by the subregions of desert steppe, the Yanshan Hills water source reserve, the mountainous and hilly areas in northern Shanxi, Hunshandake sandy land, the Greater Khingan Mountains, Kubuqi desert, Horqin sandy land, the typical steppe and Mu Us Sandy Land. The cumulative contributions for the first three subregions and four deserts (of sandy land) were 80.52% and 9.84%, respectively. The former’s cumulative contributions to the dust amounts of four particle sizes ranged from 73.06% to 83.40%, respectively, while the latter’s cumulative contributions were only between 5.56% and 12.42%. These indicated that the management of the Beijing-Tianjin sandstorm sources should focus on the subregions of the interlaced belt agriculture and animal husbandry, desert steppe and the Yanshan Hills water source reserve rather than desert (of sandy land) subregions. Third, the contributions of the cultivated land, desert (or sandy land) and grass and shrub land to the total dust amounts for above eight cities were 576.27×10⁴, 186.30×10⁴, and <sc>103.44×10⁴ t,</sc> respectively. At the same time, their contributions to the dust amounts of 0–2.5, 2.5–5, 5–10, and <sc>10–20 μm</sc> were 138.18×10⁴, 94.42×10⁴, 182.54×10⁴ and <sc>161.14×10⁴ t;</sc> 23.16×10⁴, 12.44×10⁴, 41.89×10⁴ and <sc>8.81×10⁴ t;</sc> and 28.94×10⁴, 20.79×10⁴, 42.65×10⁴, <sc>11.06×10⁴ t,</sc> respectively. Hence, the management of the Beijing-Tianjin sandstorm sources should focus on the management of cultivated land, followed by desert (or sandy land) and finally grass and shrub land. In addition, the dust amounts reaching above eight cities mainly derived from the westward wind direction, such as SW, WSW, W, WNW, NW, and NNW, although a few came from N and NNE directions. 85.15%–93.28% of dust in Baotou, Beijing, Datong, Huhehaote and Zhangjiakou originated from W, WNW, and NW; 96.16% of dust in Chifeng originated from W, WNW, and WSW; 93.68% of dust in Xilinhaote originated from WSW, W, SW, and WNW; and 81.16% of dust in Chifeng originated from NW, NNW, and NNE. There were obvious differences in the contribution of wind direction to the dust amount in different particle size groups in each city. These results provide a basis for the optimization and adjustment of the Beijing-Tianjin sandstorm source control project.

Dust emissions in the Beijing-Tianjin sandstorm source and their regional differentiation

<p indent="0mm">Dust emissions caused by soil wind erosion are the primary natural source of inhalable particulate matter in dust source areas and downwind atmospheric environments. Accurate estimations of dust emissions are foundational for understanding the mechanism of sandstorm occurrences and their transport processes. They are also the basis on which planning and decision-making for sand control and atmospheric environment governance are made. Based on field surveys, surface soil collections, laboratory experiments, remote sensing images, meteorological data, and model simulation, this paper estimated the amount of dust emissions for four different particle size groups (0–2.5, 2.5–5, 5–10, <sc>10–20 μm)</sc> in four different periods (2000, 2005, 2010, 2015), revealed the temporal and spatial distributions of dust emissions from Beijing-Tianjin sandstorm sources and their responses to particle size changes, and clarified the contributions to dust emissions by different land uses. The main conclusions are as follows: (1) Due to climate change, the amount of dust emissions in the Beijing-Tianjin sandstorm source has fluctuated since the implementation of the Beijing-Tianjin sandstorm source control project. In 2000, 2005, 2010 and 2015, dust emissions were 3.24 × 10⁷, 2.76 × 10⁷, 3.44 × 10⁷, and 3.26 × <sc>10⁷ t,</sc> respectively. These emissions demonstrated a clear pattern throughout the year. From January to April, they increased monthly, peaked in April, decreased throughout May, maintained the lowest yearly value from June to September, and increased again in November. These results indicate that dust emissions in Beijing-Tianjin sandstorm sources have obvious seasonal characteristics. The emission amounts descended in the following order: spring, winter, autumn and summer. Their average proportions were 45.45%, 28.14%, 15.99% and 10.42%, respectively. (2) The three subareas, such as the agricultural and animal husbandry interlaced belt subarea, the desert steppe, and the northern Shanxi mountain hills subarea, were the main source of dust emission in Beijing-Tianjin sandstorm sources, accounting for 55.29% of the total amount. The total amount of dust emissions for the above three subareas was 2.64 times those of the four deserts or sandy land in Beijing-Tianjin sandstorm sources, which included the Kubuqi Desert, the Mu Us Sandy Land, the Hunshandake Sandy Land and the Horqin Sandy Land. (3) Although the proportion of cultivated land in Beijing-Tianjin sandstorm sources was only between 13.89% and 14.81%, dust emissions from cultivated land accounted for 71.56% of the total emissions in Beijing-Tianjin sandstorm sources. The corresponding proportions for deserts (or sandy land) and other vegetation surface covers (such as grassland, shrubland, etc.) were 19.78% and 8.66%, respectively. (4) In order to control both dust emissions in Beijing-Tianjin sandstorm sources and their impacts on atmospheric inhalable particulate matter, especially in the Beijing-Tianjin area, this paper showed that the key areas are the agriculture and animal husbandry interlaced belt subarea, the Yanshan Hills Water Source Reserve subarea, the desert steppe, and the northern Shanxi mountain hills subarea, and the core of land use in governance is cultivated land, not sandy land. The results in this paper would provide basic data for accurately assessing the benefits of the Beijing-Tianjin sandstorm source control project and also present a scientific basis for its optimal layout.

Plant Diversity and Aboveground Biomass Interact with Abiotic Factors to Drive Soil Organic Carbon in Beijing Mountainous Areas

We analyzed and compared the effects of biotic factors (species diversity, structural diversity, and aboveground biomass) and abiotic factors (topography and soil properties) on soil organic carbon in selected mountainous areas of Beijing China. An overall goal is to provide a preliminary scientific basis for biodiversity protection and coordinated development of forest ecosystems and the subsequent carbon balance in this region. Our study ecosystems were coniferous forests, mixed coniferous and broadleaved forests, and broadleaved forests in the western mountainous area of Beijing. We determined both direct and indirect effects of abiotic and biotic factors on soil organic carbon using multiple linear regression and a structural equation model. Results showed that the biotic factors aboveground biomass and structural diversity were the main driving forces of organic carbon accumulation in the soil surface layer (0–10 cm), but species diversity had no significant effect (p &gt; 0.05). Abiotic factors (altitude, total nitrogen, and total potassium) had some influence on soil surface organic carbon but were subordinate to the biotic factors. The biotic factors had no significant effect on soil organic carbon in the subsurface layers (10–20 cm) and (20–30 cm) (p &gt; 0.05), whereas the abiotic factors altitude and total nitrogen played a dominant role in subsurface soil organic carbon accumulation of both layers (p &lt; 0.01). The influences were both direct and indirect influences, but the direct influences played a major role. Our results form an initial reference for afforestation management (Beijing-Tianjin Sandstorm-source Control Project) from the perspective of biodiversity protection and carbon storage enhancement.

Impact of the Beijing-Tianjin sandstorm source control project on ecosystem services and an evaluation of economic benefits

<p indent="0mm">The Beijing-Tianjin sandstorm source control project (BTSSCP) is a large and famous ecological construction project with enormous investment that aims to improve and optimize the ecological condition of Beijing-Tianjin and the surrounding areas. Since the implementation of the BTSSCP in 2000, profound changes have occurred in the region regarding land use, vegetation cover, soil, wind and water erosion, and the supply of regional ecosystem services (ESs). Changes in regional ESs are influenced not only by human activities but also by natural factors such as climate change. Distinguishing and quantifying the roles of climate change and land-use change on regional ES changes can better serve sustainable land-use management decisions at the regional and national levels. Additionally, information is needed on the economic benefits caused by sandstorm control and ecological restoration, such as the value change of the regulating ESs since the BTSSCP began, the variation in the spatial patterns of ESs and their integration, and the contribution of sand control and vegetation restoration to regional ES changes. Moreover, a landscape-level ES multifunctionality concept and measurement framework provided deep insight into the spatial supply-benefit relationship of ESs, and this information is crucial for sustainable ecosystem management and land-use planning. In this study, a set of ES indicators that represent ecological provisioning (<italic>n</italic>=2), regulating (<italic>n</italic>=4), and supporting (<italic>n</italic>=2) services at the county scale in the BTSSCP were calculated based on a field survey, Normalized difference vegetation index (NDVI) data, land-use data, meteorological data (i.e., temperature, precipitation, wind speed, and direction) and socioeconomic census data. Then, the ES multifunctionality of each county was assessed using the multiple ES landscape index (MESLI) and the ES Shannon diversity index (ESHDI). Variation partitioning was used to distinguish the contributions of land-use area composition and major climatic conditions (annual average temperature, annual precipitation, and average wind speed) to various ESs, and the MESLI and ESHDI in different periods were measured and compared. Partial least squares path modeling (PLS-PM) was applied to determine the direct and indirect effects of the BTSSCP on the regional ecological supply, ecological regulation, habitat support services and multifunctional indicators of ESs and their changes. The results showed that (1) the implementation of the BTSSCP effectively improved the regulating ESs in Beijing, Tianjin and surrounding areas and promoted the overall improvement of the comprehensive benefits of regional ESs while effectively improving the integration and diversity of ESs in the core areas of wind and sand management. The MESLI increased in 94.8% of all counties in 2015 compared to 2000. (2) Both land-use composition and climatic factors had impacts on the regional ES provisions, but the influence of land use on the regulating and provisioning ESs was significantly higher than that of climatic factors. The direct effect of land use on ES provision, regulation, and support was enhanced, the multifunctionality of regional ESs was dramatically improved, and the role of climatic factors markedly declined as the project proceeded. (3) The economic benefits of the BTSSCP were positive, with a 415300 yuan/km² increase in the content of regulating ESs, and 82.7% of counties had reduced wind erosion after BTSSCP implementation, which indicated that the comprehensive economic benefits of BTSSCP implementation were significant. These results provide a scientific basis for evaluating the benefits of the BTSSCP and serve as a reference for developing new national management strategies.

Spatial and temporal evolution of soil wind erosion in the Beijing-Tianjin sandstorm sources

<p indent="0mm">Dust emissions due to soil wind erosion and its transport are the most important natural sources of inhalable particulate matter in the atmospheric environment of sandstorm sources and the regions where sandstorms occur. To control the impact of dust emissions caused by soil wind erosion on the atmospheric environment in the Beijing-Tianjin resources, the Chinese government implemented a strategic significance ecological governance project in the Beijing-Tianjin sandstorm sources at the beginning of this century. However, there is still much controversy about soil wind erosion in the Beijing-Tianjin sandstorm sources and the resulting dust emissions. Based on field surveys, laboratory tests, remote sensing images and meteorological data, this paper calculated soil wind erosion in the Beijing-Tianjin sandstorm sources under three conditions, including the typical years of 2000, 2005, 2010, and 2015, land-use change conditions (land use in 2000, 2005, 2010, and 2015 but other factors with 2015), and climate change conditions (land use in 2015 but other factors with 2000, 2005, 2010, and 2015), by using the specified soil wind erosion model in the National Plan for Dynamic Monitoring of Soil and Water Loss from 2018 to 2022 and the Technical Regulations for Dynamic Monitoring of Regional Soil and Water Loss (Trial Version). In 2000, 2005, 2010, and 2015, the fluctuation in wind erosion modulus in the Beijing-Tianjin sandstorm sources decreased. Wind erosion modulus gradually decreased from northwest to southeast, and the value in desert or sandy land was higher than that in the surrounding areas. With the advancement of governance projects in the Beijing-Tianjin sandstorm sources, the distribution of wind erosion modulus changed significantly. Wind erosion modulus in the desert steppe was the largest and was approximately 2.67–2.98 times that of the Beijing-Tianjin sandstorm sources. Wind erosion modulus in the Hetao Plain and Hunshandake Sandy Land, were roughly the same as that in the Beijing-Tianjin sandstorm sources. Wind erosion modulus in other subregions was 42.69% of that in the Beijing-Tianjin sandstorm sources. Wind erosion area and variability in the above years in the Beijing-Tianjin sandstorm sources were <sc>385800–464500 km²</sc> and −9.35%–9.14%, respectively. The area of ​​mild and moderate wind erosion accounted for 91.56%. Overall, wind erosion area in the northwestern Beijing-Tianjin sandstorm sources was large, and its area proportion was high, followed by that in the middle area, and the southeast area had the smallest area. The wind erosion area in ​​desert steppe accounted for the largest proportion, with a value of 25.88%, and that in the southern part of the Greater Khingan Mountains was only 3.18%. Intense and extremely intense soil wind erosion was concentrated in the desert steppe and the western part of the Hetao Plain. Intense soil wind erosion was mainly distributed in the Kubuqi Desert and Hunshandake Sandy Land. Moderate and mild erosion involved each subregion in the Beijing-Tianjin sandstorm sources. There were obvious differences in the changes in the wind erosion area and intensity in each subregion during 2000–2005, 2005–2010, and 2010–2015. Climate change and land-use change had important impacts on soil wind erosion in the Beijing-Tianjin sandstorm sources. The variability of the wind erosion modulus and the area affected by climate change was equivalent to the corresponding variability of the year but greater than the influence of land-use change. In addition, the area of wind erosion under land-use change generally decreased, especially from 2010 to 2015, which had a decrease of 4.10%, indicating that the Beijing-Tianjin sandstorm source control project played an important role. These results provide a scientific basis for the evaluation of the benefits of the Beijing-Tianjin sandstorm source control project and the optimization of its layout.

Input–Output Efficiency of the Beijing–Tianjin Sandstorm Source Control Project and Influencing Factors

From the perspective of economic benefit, this paper uses the DEA method to measure the input–output efficiency of the Beijing–Tianjin sandstorm source control project in Beijing, Hebei, Shanxi, and Inner Mongolia. The results show that from 2003 to 2019, the efficiency of the four regions revealed a U-shaped trend, first decreasing and then increasing, which reflects the lagging characteristics of forestry engineering. The TFP of the sand source control project in these four places was calculated; the average efficiency growth rate was 1.4%, and it was found to be affected greatly by the rate of technological progress. The Tobit model was used to explore the influencing factors, and the results show that educational input and economic development level have a great effect on efficiency, fiscal pressure has a small effect on efficiency, and financial development level has a restraining effect on efficiency.

Dynamic changes in water conservation in the Beijing–Tianjin Sandstorm Source Control Project Area: A case study of Xilin Gol League in China

The insufficient information on water conservation dynamics and potential in ecological engineering areas often restrict the selection and implementation of ecological restoration measures in arid and semiarid climates. Based on the regional water balance equation and GIS spatial analysis tools, this article assessed the spatial-temporal changes in water conservation in Xilin Gol League, a representative region of the Beijing–Tianjin Sandstorm Source Control Project Area. The results indicated that the yearly amount of water conservation in Xilin Gol League reached 1.27 billion cubic meters, and annual precipitation of approximately 6.36 mm was retained per hectare. The water conservation capacity in Xilin Gol League showed a notably increasing tendency during the period of 2000–2015 and increased from west to east. The northeast of East Ujimqin Banner had the highest capacity, contributing 16.19% of the total water conservation amount. Compared to 2000, approximately 65.86% of Xilin Gol League presented water conservation capacity increases in 2015, 15.25% of which were significant. The water conservation in Xilin Gol League correlated with the changes in precipitation, temperature, and vegetation coverage, and unfavorable changes in these factors led to a significant decline in regional water conservation capacity. Therefore, multiple ecological restoration strategies are proposed for the improvement of water conservation capacity in the low-efficiency areas.

Contributions of ecological programs to vegetation restoration in arid and semiarid China

Over the past four decades, large-scale ecological programs, including the ‘Great Green Wall Program’ (1978–present), ‘Grain for Green Program’ (1999–present), ‘Grassland Ecological Protection Program’ (2000–present), and ‘Beijing-Tianjin Sandstorm Source Control Project’ (2002–present), were launched to restore vegetation, to combat desertification, and to control dust storms in arid and semiarid China. The gross investments of these programs have exceeded 1700 billion RMB (∼260 billion USD, accounting for ∼1% GDP in the region) by now, however, the effects of these programs on vegetation restoration have not been settled. In this study, the vegetation indices, land-uses, and climatic factors were used to estimate the contribution of the above programs on vegetation restoration. The results showed that consistent vegetation restoration has occurred in about 45.3% of the vegetated areas in arid and semiarid China from 1982 to 2000, and the percentage decreased to 33.6% after 2000 despite more ecological programs have been launched. Changes in climatic factors (precipitation, temperature, solar radiation, and wind speed) and elevated atmospheric CO2 concentration contributed more than 50% and 70% to vegetation restoration in periods of 1982–2000 and 2001–2015, respectively, however, the contribution rate of ecological programs kept stable at about 20%. Climate changes in the past forty years played a dominant role, although the ecological programs showed a noticeable effect on vegetation restoration. Further investment in ecological restoration practices might need to be critically evaluated on the cost-effectiveness.

Spatiotemporal changes in terrestrial water storage in the Beijing-Tianjin Sandstorm Source Region from GRACE satellites

The Sandstorm Source Control Project in and around the Beijing-Tianjin region was one of the most important ecological projects in China. Terrestrial water storage (TWS) has important impacts on the ecological construction, agriculture, industry, and resident’s lives. Based on the Gravity Recovery and Climate Experiment (GRACE) data, meteorological and Moderate Resolution Imaging Spectroradiometer (MODIS) data, etc., this paper analyzed spatiotemporal characteristics of TWS, groundwater storage, and precipitation, and explored the influencing factors of regional TWS combined with land use and land cover (LULC), social and economic data. The most important results were as follows: (1) From 2003 to 2016, TWS in the Beijing-Tianjin Sandstorm Source Region showed a decreasing trend with a rate of 3.14 mm yr−1. (2) The TWS decline was caused mainly by groundwater overexploitation, but not precipitation variation. (3) Spatiotemporal variations of TWS were related to LULC. The area with the most serious decrease of TWS was mainly located in the southwestern part of the region, where farmland percentage and population density were greater. (4) Reducing the percent of farmland and tree planting, and adding the shrub and grass planting, could be a viable choice for the Beijing-Tianjin Sandstorm Source Control Project. These results provide a scientific basis for regional water resource and ecological management.

Quantitative analysis of the effects of human activities on vegetation in the Beijing-Tianjin sandstorm source region under the climate change

It is of great practical significance for regional ecological management to understand the quantitative impacts of human activities on vegetation under climate change. Based on GIMMS NDVI3g data, meteorological data (temperature, precipitation) and standardized precipitation evapotranspiration index (SPEI), we used correlation analysis and trend analysis to examine the spatio-temporal variation of vegetation and its driving factors in different periods from 1982 to 2014 in the Beijing-Tianjin sandstorm source region. Regression analysis and residual analysis were used to quantify the impacts of human activities on vegetation changes in different sub-regions. The results showed that from 1982 to 2014, the degradation status in 77.1% of degraded vegetation was significantly improved and 64.1% of vegetation had an increasing trend in the study area, with mean annual NDVI decreasing from southeast to northwest. Vegetation coverage increased in 74.5% of the areas after the implementation of the Beijing-Tianjin sandstorm source control project, with mountains in northern Shanxi showing the most obvious increases. Among all the climate factors, rainfall had the strongest correlation with vegetation change. Human activities, such as ecological engineering, played an active role in most areas, especially in mountains of northern Shanxi, where the contribution of human activities reached 94.9%.

Vegetation cover changes and sand-fixing service responses in the Beijing–Tianjin sandstorm source control project area

Vegetation cover and related ecosystem services are key indicators for ecological restoration efforts. We simulated the dynamic changes of vegetation coverage and sand-fixing service in the Beijing–Tianjin sandstorm source control project area (BTSSCPA) in the period of 2000–2015 on the basis of long-term satellite data and the revised wind erosion equation. The response levels of sand-fixing service to vegetation coverage change were also analyzed. Results showed that the vegetation coverage in the BTSSCPA increased with fluctuation at an average rate of 0.34%/year, and the sand-fixing service was correspondingly enhanced with the average annual rate of 0.71%. Furthermore, the responsive levels of sand-fixing service to vegetation coverage change increased from 70% to 91%. We conclude that the vegetation restoration measures on sand-fixing gradually prevail and progress in the BTSSCPA. However, approximately 13% of the BTSSCPA still has poor responsivity and needs additional restoration measures for implementation. This research will contribute to quantify the effectiveness of vegetation restoration on ecosystem service enhancement, and identify the key implementation areas for further ecological restoration measures.

Study on Dynamic Remote Sensing Monitoring of LUCC and Soilwind Erosion Intensity in the Beijing-Tianjin Sandstorm Source Control Project Region

Study on Dynamic Remote Sensing Monitoring of LUCC and Soilwind Erosion Intensity in the Beijing-Tianjin Sandstorm Source Control Project Region