Eco-environmental quality is a measure of the suitability of the ecological environment for human survival and socioeconomic development.Understanding the spatial-temporal distribution and variation trend of eco-envir...Eco-environmental quality is a measure of the suitability of the ecological environment for human survival and socioeconomic development.Understanding the spatial-temporal distribution and variation trend of eco-environmental quality is essential for environmental protection and ecological balance.The remote sensing ecological index(RSEI)can quickly and objectively quantify eco-environmental quality and has been extensively utilized in regional ecological environment assessment.In this paper,Moderate Resolution Imaging Spectroradiometer(MODIS)images during the growing period(July-September)from 2000 to 2020 were obtained from the Google Earth Engine(GEE)platform to calculate the RSEI in the three northern regions of China(the Three-North region).The Theil-Sen median trend method combined with the Mann-Kendall test was used to analyze the spatial-temporal variation trend of eco-environmental quality,and the Hurst exponent and the Theil-Sen median trend were superimposed to predict the future evolution trend of eco-environmental quality.In addition,ten variables from two categories of natural and anthropogenic factors were analyzed to determine the drivers of the spatial differentiation of eco-environmental quality by the geographical detector.The results showed that from 2000 to 2020,the RSEI in the Three-North region exhibited obvious regional characteristics:the RSEI values in Northwest China were generally between 0.2 and 0.4;the RSEI values in North China gradually increased from north to south,ranging from 0.2 to 0.8;and the RSEI values in Northeast China were mostly above 0.6.The average RSEI value in the Three-North region increased at an average growth rate of 0.0016/a,showing the spatial distribution characteristics of overall improvement and local degradation in eco-environmental quality,of which the areas with improved,basically stable and degraded eco-environmental quality accounted for 65.39%,26.82%and 7.79%of the total study area,respectively.The Hurst exponent of the RSEI ranged from 0.20 to 0.76 and the future trend of eco-environmental quality was generally consistent with the trend over the past 21 years.However,the areas exhibiting an improvement trend in eco-environmental quality mainly had weak persistence,and there was a possibility of degradation in eco-environmental quality without strengthening ecological protection.Average relative humidity,accumulated precipitation and land use type were the dominant factors driving the spatial distribution of eco-environmental quality in the Three-North region,and two-factor interaction also had a greater influence on eco-environmental quality than single factors.The explanatory power of meteorological factors on the spatial distribution of eco-environmental quality was stronger than that of topographic factors.The effect of anthropogenic factors(such as population density and land use type)on eco-environmental quality gradually increased over time.This study can serve as a reference to protect the ecological environment in arid and semi-arid regions.展开更多
The ＂Three-North＂ Shelterbelt is the largest and most distinctive artificial ecological engineering project in China. It has been conducted since November 25, 1978 in the ＂Three-North＂ （i.e., Northeast China, Nor...The ＂Three-North＂ Shelterbelt is the largest and most distinctive artificial ecological engineering project in China. It has been conducted since November 25, 1978 in the ＂Three-North＂ （i.e., Northeast China, North China and Northwest China） regions. In this study, the background and the essential benefits of the ＂Three-North＂ Shelterbelt project are summarized. The basic status and future development of the ＂Three-North＂ Shelterbelt project are also studied. As well, we tried to discuss the problems existing in the current shelterbelt system and the strategies to conduct this ecological project rationally.展开更多
The relationship between the change of forest resources and climatic factor in the, “Three-North” region of China were studied in this paper. The predicting equations of climatic factor (dependent variable) with reg...The relationship between the change of forest resources and climatic factor in the, “Three-North” region of China were studied in this paper. The predicting equations of climatic factor (dependent variable) with regional independent variable (longitude, latitude and altitude) and stand independent variable (forest coverage rate), were developed by extensively using the linear and nonlinear regression methods. With these models, we can calculate the ecological benefit of Shelter-belt forest.展开更多
Understanding the coupling between carbon and water in terrestrial ecosystems is essential for achieving sustainable development.Net primary productivity(NPP),carbon use efficiency(CUE),and water use efficiency(WUE) a...Understanding the coupling between carbon and water in terrestrial ecosystems is essential for achieving sustainable development.Net primary productivity(NPP),carbon use efficiency(CUE),and water use efficiency(WUE) are key indicators for assessing carbon balance and carbon–water interactions.However,knowledge gaps remain regarding how these indicators respond to climate change and interact with one another.This study examined the spatial and temporal dynamics of NPP,CUE,and WUE,as well as their interrelationships,within the Three-North Shelterbelt Forest region of China.Furthermore,the study investigated the driving mechanisms of these indicators using Extreme Gradient Boosting(XGBoost),SHapley Additive ex Planations(SHAP),and Partial Least Squares Structural Equation Modeling(PLS-SEM).The results revealed that from 2000 to 2020,both NPP(2.69 g C/(m^(2)·a);P<0.010) and WUE(0.004 g C/(kg H_(2)O·a);P<0.010) increased significantly,while CUE exhibited a non-significant decline(–5.40×10^(–4)/a;P>0.050) across different climatic zones(arid,semi-arid,humid,and sub-humid) and vegetation types(cropland,forest,grassland,shrubland,and wetland).The correlation between WUE and NPP(correlation coefficient of 0.70) was stronger than that between CUE and NPP(correlation coefficient of 0.15).NPP and WUE were primarily influenced by leaf area index,whereas CUE was most strongly affected by elevation.The relationships between the key drivers and the three indicators were largely nonlinear,with stronger driver contributions corresponding to more pronounced nonlinear interactions.Moreover,these nonlinear relationships were modulated by differences in dry versus wet climatic conditions.Geographical factors(e.g.,longitude,latitude,and elevation) further shaped vegetation characteristics(e.g.,fractional vegetation cover and leaf area index) by regulating climatic variables such as temperature,precipitation,and evapotranspiration,ultimately influencing NPP,WUE,and CUE.This study advances the understanding of vegetation carbon–water coupling and provides a scientific basis for ecosystem management and sustainable development policy-making in various climatic zones.展开更多
China's Three-North Protective Forest Program(TNP) is the world's most ambitious afforestation project(ongoing from 1978 to 2050), which aims to increase forest coverage through afforestation and reforestation...China's Three-North Protective Forest Program(TNP) is the world's most ambitious afforestation project(ongoing from 1978 to 2050), which aims to increase forest coverage through afforestation and reforestation, protect agriculture, reduce soil erosion, and control desertification. Although TNP has been ongoing for 45 years, its rationales and effects remain uncertain. Here, we conducted a rangewide assessment of TNP by analyzing data from >10,000 scenes of satellite images and >50,000 field survey plots. The TNP range and definitions of shelterbelts, arboreal forests, and shrublands were changed during the study period, but we used the initial TNP range(4.07 million km2) and the definitions in 1978 for keeping the consistency, comparability, and comprehensiveness. The TNP increased forest coverage from 5.05% in 1978 to 9.69% in 2022, with arboreal forests, shrublands, and shelterbelts increasing by 42.5%, 184.4%,and 53.6%, respectively. However, only 40.1% of the 471,113 km2afforested area was established between 1978 and 2022. The wellestablished shelterbelts improved crop yield by 4.3%-9.5%, but only 10.2% of all the farmlands in TNP regions(TNR) were protected. The total area of soil erosion due to hydraulic forces was reduced by 447,363 km2, with 61% of this reduction attributed to TNP. TNP contributed to the reduction of desertification by 15%, largely due to the low rate of afforestation success and the largely decreased grasslands. The total carbon sequestration from TNP was 1.96 Pg C. Moreover, water storage in TNR showed a decreasing trend, but the contribution rate of TNP was only 7.8%. Our results illustrate that forestry eco-engineering projects are feasible in the management and restoration of arid and semi-arid degraded lands, but attention must be paid to fully considering the ecological carrying capacity of water resources, matching the species to sites, strengthening the post-afforestation management, as well as keeping the balances between composite ecosystems.展开更多
The Shelterbelt Forest System Program in northeast, north and northwest China （the Three-North Shelterbelt Program, TNSP） is the largest ecological reforestation program in the world. TNSP vegetation research has im...The Shelterbelt Forest System Program in northeast, north and northwest China （the Three-North Shelterbelt Program, TNSP） is the largest ecological reforestation program in the world. TNSP vegetation research has important ecological meaning and profound social and economic signiifcance. Here, spatio-temporal variation in vegetation cover under the TNSP was examined using the NDVI average method, major climatic factors such as temperature and precipitation, and linear regression trend analysis from 1982 to 2006. We found that in the past 25 years, NDVI vegetation in the study area has consistently risen at a rate of 0.007 per decade. Vegetation cover, temperature and precipitation are positively correlated. The area of vegetation associated with precipitation is larger than the area related to temperature;precipitation is the key factor affecting vegetation growth across the TNSP. From 1982 to 2006, regions with improved vegetation cover were found in the central and southern part of the Greater Khingan Mountains, central part of the Lesser Khingan Mountains, northeastern part of the Changbai Mountains, Yanshan Mountians, Western Liaoning Hilly Region, Altai Mountains, Tien Shan Mountains, eastern part of the Qilian Mountains, eastern part of the northwest desert as wel as southern part of the Gul y Region of the Loess Plateau. However, vegetation cover declined on both sides of the Greater Khingan Mountains, western part of the Hulun Buir Plateau, northern part of the Sanjiang Plain, southern part of Horqin Sandy Land, southern part of the northwest desert and northern part of the Gul y Region of the Loess Plateau.展开更多
Water shortage is an important constraint factor in the construction of the Three-North Shelterbelt （TNS）. Here, we analyzed temporal-spatial patterns in water resources and trends in the Three-North region. We eval...Water shortage is an important constraint factor in the construction of the Three-North Shelterbelt （TNS）. Here, we analyzed temporal-spatial patterns in water resources and trends in the Three-North region. We evaluated the water resource carrying capacity （WRCC） of 623 counties in the project area during the fifth phase of the TNS Development Program. Results show that 387 counties are appropriate for forestation, 185 counties can be planted, and 60 counties are inappropriate for forestation because of water resource constraints.展开更多
The African Great Green Wall Initiative(GGWI)is an ambitious transcontinental program aimed at halting desertification,restoring degraded lands,and improving livelihoods across the Sahel region.Despite its transformat...The African Great Green Wall Initiative(GGWI)is an ambitious transcontinental program aimed at halting desertification,restoring degraded lands,and improving livelihoods across the Sahel region.Despite its transformative vision,the initiative has encountered technical,financial,and governance challenges.In recent years,China’s involvement-drawing from its extensive experience with the Three-North Shelterbelt Program and integrated desertification control-has introduced a new model of South-South cooperation.Through adaptive technologies,capacity building,and co-developed community-based strategies in Mauritania,Ethiopia,and Nigeria,Chinese partners have provided tangible contributions to Africa’s ecological restoration.This article documents these collaborative stories and argues that China’s ecological governance framework is shaping a new paradigm for global environmental development.展开更多
基金supported by the National Natural Science Foundation of China(31971578)the Scientific Research Fund of Changsha Science and Technology Bureau(kq2004095)+2 种基金the National Bureau to Combat Desertification,State Forestry Administration of China(101-9899)the Training Fund of Young Professors from Hunan Provincial Education Department(90102-7070220090001)the Postgraduate Scientific Research Innovation Project of Hunan Province(CX20220707)。
文摘Eco-environmental quality is a measure of the suitability of the ecological environment for human survival and socioeconomic development.Understanding the spatial-temporal distribution and variation trend of eco-environmental quality is essential for environmental protection and ecological balance.The remote sensing ecological index(RSEI)can quickly and objectively quantify eco-environmental quality and has been extensively utilized in regional ecological environment assessment.In this paper,Moderate Resolution Imaging Spectroradiometer(MODIS)images during the growing period(July-September)from 2000 to 2020 were obtained from the Google Earth Engine(GEE)platform to calculate the RSEI in the three northern regions of China(the Three-North region).The Theil-Sen median trend method combined with the Mann-Kendall test was used to analyze the spatial-temporal variation trend of eco-environmental quality,and the Hurst exponent and the Theil-Sen median trend were superimposed to predict the future evolution trend of eco-environmental quality.In addition,ten variables from two categories of natural and anthropogenic factors were analyzed to determine the drivers of the spatial differentiation of eco-environmental quality by the geographical detector.The results showed that from 2000 to 2020,the RSEI in the Three-North region exhibited obvious regional characteristics:the RSEI values in Northwest China were generally between 0.2 and 0.4;the RSEI values in North China gradually increased from north to south,ranging from 0.2 to 0.8;and the RSEI values in Northeast China were mostly above 0.6.The average RSEI value in the Three-North region increased at an average growth rate of 0.0016/a,showing the spatial distribution characteristics of overall improvement and local degradation in eco-environmental quality,of which the areas with improved,basically stable and degraded eco-environmental quality accounted for 65.39%,26.82%and 7.79%of the total study area,respectively.The Hurst exponent of the RSEI ranged from 0.20 to 0.76 and the future trend of eco-environmental quality was generally consistent with the trend over the past 21 years.However,the areas exhibiting an improvement trend in eco-environmental quality mainly had weak persistence,and there was a possibility of degradation in eco-environmental quality without strengthening ecological protection.Average relative humidity,accumulated precipitation and land use type were the dominant factors driving the spatial distribution of eco-environmental quality in the Three-North region,and two-factor interaction also had a greater influence on eco-environmental quality than single factors.The explanatory power of meteorological factors on the spatial distribution of eco-environmental quality was stronger than that of topographic factors.The effect of anthropogenic factors(such as population density and land use type)on eco-environmental quality gradually increased over time.This study can serve as a reference to protect the ecological environment in arid and semi-arid regions.
基金support from the National Nature Science Foundation of China(Grant No.30670315)the Global Environmental Research Fund of the Ministry of the Environment of Japan
文摘The ＂Three-North＂ Shelterbelt is the largest and most distinctive artificial ecological engineering project in China. It has been conducted since November 25, 1978 in the ＂Three-North＂ （i.e., Northeast China, North China and Northwest China） regions. In this study, the background and the essential benefits of the ＂Three-North＂ Shelterbelt project are summarized. The basic status and future development of the ＂Three-North＂ Shelterbelt project are also studied. As well, we tried to discuss the problems existing in the current shelterbelt system and the strategies to conduct this ecological project rationally.
文摘The relationship between the change of forest resources and climatic factor in the, “Three-North” region of China were studied in this paper. The predicting equations of climatic factor (dependent variable) with regional independent variable (longitude, latitude and altitude) and stand independent variable (forest coverage rate), were developed by extensively using the linear and nonlinear regression methods. With these models, we can calculate the ecological benefit of Shelter-belt forest.
基金the National Natural Science Foundation of China (42171124)。
文摘Understanding the coupling between carbon and water in terrestrial ecosystems is essential for achieving sustainable development.Net primary productivity(NPP),carbon use efficiency(CUE),and water use efficiency(WUE) are key indicators for assessing carbon balance and carbon–water interactions.However,knowledge gaps remain regarding how these indicators respond to climate change and interact with one another.This study examined the spatial and temporal dynamics of NPP,CUE,and WUE,as well as their interrelationships,within the Three-North Shelterbelt Forest region of China.Furthermore,the study investigated the driving mechanisms of these indicators using Extreme Gradient Boosting(XGBoost),SHapley Additive ex Planations(SHAP),and Partial Least Squares Structural Equation Modeling(PLS-SEM).The results revealed that from 2000 to 2020,both NPP(2.69 g C/(m^(2)·a);P<0.010) and WUE(0.004 g C/(kg H_(2)O·a);P<0.010) increased significantly,while CUE exhibited a non-significant decline(–5.40×10^(–4)/a;P>0.050) across different climatic zones(arid,semi-arid,humid,and sub-humid) and vegetation types(cropland,forest,grassland,shrubland,and wetland).The correlation between WUE and NPP(correlation coefficient of 0.70) was stronger than that between CUE and NPP(correlation coefficient of 0.15).NPP and WUE were primarily influenced by leaf area index,whereas CUE was most strongly affected by elevation.The relationships between the key drivers and the three indicators were largely nonlinear,with stronger driver contributions corresponding to more pronounced nonlinear interactions.Moreover,these nonlinear relationships were modulated by differences in dry versus wet climatic conditions.Geographical factors(e.g.,longitude,latitude,and elevation) further shaped vegetation characteristics(e.g.,fractional vegetation cover and leaf area index) by regulating climatic variables such as temperature,precipitation,and evapotranspiration,ultimately influencing NPP,WUE,and CUE.This study advances the understanding of vegetation carbon–water coupling and provides a scientific basis for ecosystem management and sustainable development policy-making in various climatic zones.
基金supported by the National Natural Science Foundation of China (32192435, 31025007)CAS Key Research Program of Frontier Sciences (QYZDJ-SSW-DQC027)+1 种基金the Knowledge Innovation Program of Chinese Academy of Sciences (KZCX1-YW-08-02)the Consultation Project supported by Divisions of the Chinese Academy of Sciences (2019-ZW09-A032)。
文摘China's Three-North Protective Forest Program(TNP) is the world's most ambitious afforestation project(ongoing from 1978 to 2050), which aims to increase forest coverage through afforestation and reforestation, protect agriculture, reduce soil erosion, and control desertification. Although TNP has been ongoing for 45 years, its rationales and effects remain uncertain. Here, we conducted a rangewide assessment of TNP by analyzing data from >10,000 scenes of satellite images and >50,000 field survey plots. The TNP range and definitions of shelterbelts, arboreal forests, and shrublands were changed during the study period, but we used the initial TNP range(4.07 million km2) and the definitions in 1978 for keeping the consistency, comparability, and comprehensiveness. The TNP increased forest coverage from 5.05% in 1978 to 9.69% in 2022, with arboreal forests, shrublands, and shelterbelts increasing by 42.5%, 184.4%,and 53.6%, respectively. However, only 40.1% of the 471,113 km2afforested area was established between 1978 and 2022. The wellestablished shelterbelts improved crop yield by 4.3%-9.5%, but only 10.2% of all the farmlands in TNP regions(TNR) were protected. The total area of soil erosion due to hydraulic forces was reduced by 447,363 km2, with 61% of this reduction attributed to TNP. TNP contributed to the reduction of desertification by 15%, largely due to the low rate of afforestation success and the largely decreased grasslands. The total carbon sequestration from TNP was 1.96 Pg C. Moreover, water storage in TNR showed a decreasing trend, but the contribution rate of TNP was only 7.8%. Our results illustrate that forestry eco-engineering projects are feasible in the management and restoration of arid and semi-arid degraded lands, but attention must be paid to fully considering the ecological carrying capacity of water resources, matching the species to sites, strengthening the post-afforestation management, as well as keeping the balances between composite ecosystems.
基金National Natural Science Foundation of China(4117111640961038)
文摘The Shelterbelt Forest System Program in northeast, north and northwest China （the Three-North Shelterbelt Program, TNSP） is the largest ecological reforestation program in the world. TNSP vegetation research has important ecological meaning and profound social and economic signiifcance. Here, spatio-temporal variation in vegetation cover under the TNSP was examined using the NDVI average method, major climatic factors such as temperature and precipitation, and linear regression trend analysis from 1982 to 2006. We found that in the past 25 years, NDVI vegetation in the study area has consistently risen at a rate of 0.007 per decade. Vegetation cover, temperature and precipitation are positively correlated. The area of vegetation associated with precipitation is larger than the area related to temperature;precipitation is the key factor affecting vegetation growth across the TNSP. From 1982 to 2006, regions with improved vegetation cover were found in the central and southern part of the Greater Khingan Mountains, central part of the Lesser Khingan Mountains, northeastern part of the Changbai Mountains, Yanshan Mountians, Western Liaoning Hilly Region, Altai Mountains, Tien Shan Mountains, eastern part of the Qilian Mountains, eastern part of the northwest desert as wel as southern part of the Gul y Region of the Loess Plateau. However, vegetation cover declined on both sides of the Greater Khingan Mountains, western part of the Hulun Buir Plateau, northern part of the Sanjiang Plain, southern part of Horqin Sandy Land, southern part of the northwest desert and northern part of the Gul y Region of the Loess Plateau.
基金the Principal of State Science Key Project (NO. 2007FY110300)the National Natural Science Foundation Item (NO. 41101117)
文摘Water shortage is an important constraint factor in the construction of the Three-North Shelterbelt （TNS）. Here, we analyzed temporal-spatial patterns in water resources and trends in the Three-North region. We evaluated the water resource carrying capacity （WRCC） of 623 counties in the project area during the fifth phase of the TNS Development Program. Results show that 387 counties are appropriate for forestation, 185 counties can be planted, and 60 counties are inappropriate for forestation because of water resource constraints.
文摘The African Great Green Wall Initiative(GGWI)is an ambitious transcontinental program aimed at halting desertification,restoring degraded lands,and improving livelihoods across the Sahel region.Despite its transformative vision,the initiative has encountered technical,financial,and governance challenges.In recent years,China’s involvement-drawing from its extensive experience with the Three-North Shelterbelt Program and integrated desertification control-has introduced a new model of South-South cooperation.Through adaptive technologies,capacity building,and co-developed community-based strategies in Mauritania,Ethiopia,and Nigeria,Chinese partners have provided tangible contributions to Africa’s ecological restoration.This article documents these collaborative stories and argues that China’s ecological governance framework is shaping a new paradigm for global environmental development.
