The Three Gorges Reservoir Area(TGRA)is typical of an ecologically vulnerable area,comprised of rural and mountainous areas,and with high immigration.Because of its economic and ecologic importance,studying the tradit...The Three Gorges Reservoir Area(TGRA)is typical of an ecologically vulnerable area,comprised of rural and mountainous areas,and with high immigration.Because of its economic and ecologic importance,studying the traditional agroecosystem changes in the TGRA is key to rural development and revitalization.In this study,we apply a framework of theoretical analysis,empirical study,and trend prediction to the Caotangxi River watershed within the TGRA.Using QuickBird high-resolution remote sensing images from 2012 to 2017 to evaluate natural resources and farmers’behavior,we analyze the transition and trends in the traditional agroecosystem in mountainous areas of the TGRA at spatial scale of the man-land relationship.We find that the agroecosystem in the TGRA can be divided into four modes using 100 m interval buffer rings:high-low-low,high-low-high,low-high-low and low-low-high mode where the different modes represent the agricultural development stages in the TGRA.Furthermore,the traditional agroecosystem in TGRA,represented by system elements such as farmers and sloping farmland,is transforming to accommodate the diversification of farmer livelihoods.For example,sloping farmland,which was dominated by a production function,now has equal emphasis on ecological and economic functions.Spatially,the range of the agroecosystem transition has migrated beyond high mountain areas to flat valley areas.Generally,this study provides an overview of land use in rural areas,controls on soil and water loss in mountainous areas,and better rural living environments in the TGRA.展开更多
A substantial reduction in groundwater level,exacerbated by coal mining activities,is intensifying water scarcity in western China’s ecologically fragile coal mining areas.China’s national strategic goal of achievin...A substantial reduction in groundwater level,exacerbated by coal mining activities,is intensifying water scarcity in western China’s ecologically fragile coal mining areas.China’s national strategic goal of achieving a carbon peak and carbon neutrality has made eco-friendly mining that prioritizes the protection and efficient use of water resources essential.Based on the resource characteristics of mine water and heat hazards,an intensive coal-water-thermal collaborative co-mining paradigm for the duration of the mining process is proposed.An integrated system for the production,supply,and storage of mining companion resources is achieved through technologies such as roof water inrush prevention and control,hydrothermal quality improvement,and deep-injection geological storage.An active preventive and control system achieved by adjusting the mining technology and a passive system centered on multiobjective drainage and grouting treatment are suggested,in accordance with the original geological characteristics and dynamic process of water inrush.By implementing advanced multi-objective drainage,specifically designed to address the“skylight-type”water inrush mode in the Yulin mining area of Shaanxi Province,a substantial reduction of 50%in water drillings and inflow was achieved,leading to stabilized water conditions that effectively ensure subsequent safe coal mining.An integrated-energy complementary model that incorporates the clean production concept of heat utilization is also proposed.The findings indicate a potential saving of 8419 t of standard coal by using water and air heat as an alternative heating source for the Xiaojihan coalmine,resulting in an impressive energy conservation of 50.2%and a notable 24.2%reduction in carbon emissions.The ultra-deep sustained water injection of 100 m^(3)·h^(-1)in a single well would not rupture the formation or cause water leakage,and 7.87×10^(5)t of mine water could be effectively stored in the Liujiagou Formation,presenting a viable method for mine-water mana展开更多
Guazhou County of Gansu Province is a typical ecological fragile area lying in the transition area of desert and oasis.The development of its agricultural economy is highly dependent on natural resources and environme...Guazhou County of Gansu Province is a typical ecological fragile area lying in the transition area of desert and oasis.The development of its agricultural economy is highly dependent on natural resources and environment.Contradiction of resources characterized agriculture and the fragile ecological environment has become one of the main barriers to log the impact of local agriculture to achieve sustainable development.Aiming at fragile ecological environment and limiting factors of agricultural sustainable development,thoughts and countermeasures of realizing agricultural sustainable development have been proposed.展开更多
Constructing and operating a multi-reservoir system changes the natural flow regime of rivers, and thus imposes adverse impacts on riverine ecosystems. To balance human needs with ecosystem needs, this study proposes ...Constructing and operating a multi-reservoir system changes the natural flow regime of rivers, and thus imposes adverse impacts on riverine ecosystems. To balance human needs with ecosystem needs, this study proposes an ecologically oriented operation strategy for a multi-reservoir system that integrates environmental flow requirements into the joint operation of a multi-reservoir system in order to main- tain different ecological functions throughout the river. This strategy is a combination of a regular opti-mal operation scheme and a series of real-time ecological operation schemes. During time periods when the incompatibilities between human water needs and ecosystem needs for environmental flows are rel- atively small, the regular optimal operation scheme is implemented in order to maximize multiple human water-use benefits under the constraints of a minimum water-release policy. During time periods when reservoir-induced hydrological alteration imposes significant negative impacts on the river＇s key ecological functions, real-time ecological operation schemes are implemented in order to modify the out- flow from reservoirs to meet the environmental flow requirements of these functions. The practical use of this strategy is demonstrated for the simulation operation of a large-scale multi-reservoir system which located in the middle and lower Han River Basin in China. The results indicate that the real-time ecological operation schemes ensure the environmental flow requirements of the river＇s key ecological functions, and that adverse impacts on human water-use benefits can be compensated for by the regular optimal operation scheme. The ecologically oriented operation strategy for a multi-reservoir system that is proposed in this study enriches the theoretical application of the multi-reservoir system joint operation which considers environmental flow requirements.展开更多
Following the trends of Chinese rural transformation development, and the sustainable development goals for resources and environment, reasonable arranging the potential development space and the ecological space, so ...Following the trends of Chinese rural transformation development, and the sustainable development goals for resources and environment, reasonable arranging the potential development space and the ecological space, so as to optimize the distributions of rural settlement would be the key challenge for rural areas in ecologically fragile regions. From the perspective of maintaining regional ecological security, this paper takes Da’an City, a typical ecological fragile region in Jilin Province, as the case area, constructing the comprehensive ecological security pattern(ESP) on basis of landscape ecology, and applying the landscape pattern indexes to quantitative analysis the spatial distribution characteristics of rural settlements. Then, different optimization directions and management strategies are put forward for rural settlements in each secure zone under the comprehensive ESP. The experimental results showed that 1) the area of the low security zone, the general security zone, the moderate security zone and the extreme security zone was 1570.18 km^2, 1463.36 km^2, 1215.80 km^2 and 629.77 km^2, representing 32.18%, 29.99%, 24.92% and 12.91% of the total area of the target area, respectively. 2) The rural settlements in Da’an City were characterized by a high degree of fragmentation with a large number of small-scale patches. 3) The area of rural settlements in the ecological relocation zone, the in situ remediation zone, the limited development zone and the key development zone was 22.80 km^2, 42.31 km^2, 36.28 km^2 and 19.40 km^2, accounting for 18.88%, 35.03%, 30.04% and 16.06% of the total area of rural settlements, respectively. Then, different measures were proposed for settlements in different optimization zones in order to scientifically plan important ecological space, production space and living space in rural areas. This paper aims to provide fundamental support for rural settlements based on redistribution from the perspective of landscape ecology and provide insights for rural planning and rural展开更多
A protective forest,including shelterbelt,windbreak,and shelter forest as its synonyms,is characterized by the protective functions of various forest types distributed or planted on ecologically fragile areas or nearb...A protective forest,including shelterbelt,windbreak,and shelter forest as its synonyms,is characterized by the protective functions of various forest types distributed or planted on ecologically fragile areas or nearby the objects that need to be protected using the ecological effects of forests.Ecological mechanisms for management practices of protective forests is one of the disciplinary orientations in forest ecology and management.Most protective forest studies are dependent on forestry eco-engineering,such as the Great Plains Shelterbelt Project in the United States,the Great Plan for the Transformation of Nature in the Soviet Union,and the Three-North Afforestation Program in China.The development of sustainable management of protective forests has been given increasing attention by governments,scientists,and media due to their impacts on environment conservation and global change.We introduce forestry ecoengineering and provide a review of their main ecological mechanisms for management practices of protective forests.Ecological mechanisms for management systems currently applied are emphasized,i.e.,the theory of protection maturity and phase-directional management;the relationship between structure and protective functions and structural optimization measures;and,the decline mechanism and ecological restoration strategies.In addition,several unresolved problems in management practices of protective forests are discussed as well as the prospects for ecological mechanisms for management practices of protective forests in the future,which include:(1)theories and technologies for management practices of protective forests at the landscape or regional scale;(2)the decline mechanisms and corresponding ecological restoration approaches across multiple scales;and,(3)the comprehensive assessment of forestry eco-engineering at large-scales based on ecosystem principles.展开更多
Synergetic energy-water-carbon pathways are key issues to be tackled under carbon-neutral target and high-quality development worldwide,especially in ecologically vulnerable regions(EVRs).In this study,to explore the ...Synergetic energy-water-carbon pathways are key issues to be tackled under carbon-neutral target and high-quality development worldwide,especially in ecologically vulnerable regions(EVRs).In this study,to explore the synergistic pathways in an EVR,a water-energy-carbon assessment(WECA)model was built,and the synergistic effects of water-energy-carbon were comprehensively and quantitatively analyzed under various scenarios of regional transition.Shaanxi Province was chosen as the representative EVR,and Lower challenge(LEC)and Greater challenge(GER)scenarios of zerocarbon transition were set considering the technological maturity and regional energy characteristics.The results showed that there were limited effects under the zero-carbon transition of the entire region on reducing water withdrawals and improving the water quality.In the LEC scenario,the energy demand and CO_(2) emissions of Shaanxi in 2060 will decrease by 70.9%and 99.4%,respectively,whereas the water withdrawal and freshwater aquatic ecotoxicity potential(FAETP)will only decrease by 8.9%and 1.6%,respectively.This could be attributed to the stronger demand for electricity in the energy demand sector caused by industrial transition measures.The GER scenario showed significant growth in water withdrawals(16.0%)and FAETP(36.0%)because of additional biomass demand.To promote the synergetic development of regional transition,EVRs should urgently promote zero-carbon technologies(especially solar and wind power technologies)between 2020 and 2060 and dry cooling technology for power generation before 2030.In particular,a cautious attitude toward the biomass energy with carbon capture and storage technology in EVRs is strongly recommended.展开更多
Management of overabundant rodents at a landscape scale is complex but often required to sustainably reduce rodent abundance below damage thresholds.Current conventional techniques such as poisoning are not species sp...Management of overabundant rodents at a landscape scale is complex but often required to sustainably reduce rodent abundance below damage thresholds.Current conventional techniques such as poisoning are not species specific,with some approaches becoming increasingly unacceptable to the general public.Fertility control,first proposed for vertebrate pest management over 5 decades ago,has gained public acceptance because it is perceived as a potentially more species-specific and humane approach compared with many lethal methods.An ideal fertility control agent needs to induce infertility across one or more breeding seasons,be easily delivered to an appro-priate proportion of the population,be species specific with minimal side-effects(behavioral or social structure changes),and be environmentally benign and cost effective.To date,effective fertility control of rodents has not been demonstrated at landscape scales and very few products have achieved registration.Reproductive targets for fertility control include disrupting the hormonal feedback associated with the hypothalamic-pituitary-gonadal axis,gonad function,fertilization,and/or early implantation.We review progress on the oral delivery of various agents for which laboratory studies have demonstrated efficacy in females and/or males and synthesize progress with the development and/or use of synthetic steroids,plant extracts,ovarian specific peptides,and immunocontracep-tive vaccines.There are promising results forfield application of synthetic steroids(levonorgestrel,quinestrol),chemosterilants(4-vinylcyclohexene diepoxide),and some plant extracts(triptolide).For most fertility control agents,more research is essential to enable their efficient and cost-effective delivery such that rodent impacts at a population level are mitigated and food security is improved.展开更多
Meteorological conditions have an important impact on changes of vegetation in ecologically fragile karst areas.This study aims to explore a method for quantitative evaluation of these meteorological conditions. We an...Meteorological conditions have an important impact on changes of vegetation in ecologically fragile karst areas.This study aims to explore a method for quantitative evaluation of these meteorological conditions. We analyzed the changing trend of vegetation during 2000–2018 and the correlations between vegetation changes and various meteorological factors in karst rocky areas of Guangxi Zhuang Autonomous Region, China. Key meteorological factors in vegetation areas with varying degrees of improvement were selected and evaluated at seasonal timescale. A quantitative evaluation model of comprehensive influences of meteorological factors on vegetation was built by using the partial least-square regression(PLS). About 91.45% of the vegetation tended to be improved, while only the rest 8.55% showed a trend of degradation from 2000 to 2018. Areas with evident vegetation improvement were mainly distributed in the middle and northeast, and those with obvious vegetation degradation were scattered. Meteorological factors affecting vegetation were significantly different among the four seasons. Overall, high air humidity, small temperature difference in spring and autumn, and low daily minimum temperature and air pressure were favorable conditions. Low temperature in winter as well as high temperature in summer and autumn were unfavorable conditions. The Climate Vegetation Index(CVI) model was established by PLS using the maximum, minimum, and average temperatures;vapor pressure;rainfall;and air pressure as key meteorological factors. The Enhanced Vegetation Index(EVI) was well fitted by the CVI model, with the average coefficient of determination(r2) and root mean square error(RMSE) of 0.856 and 0.042, respectively. Finally, an assessment model of comprehensive meteorological conditions was built based on the interannual differences in CVI. The meteorological conditions in the study area in 2014 were successfully evaluated by combining the model and selected seasonal key meteorological factors.展开更多
Ecological footprint's theory and method are used to calculate and analysisthe ecological carrying capacity in Tibet. The results indicate: Tibet ecological footprint (2.1hm^2) keeps higher than countrywide averag...Ecological footprint's theory and method are used to calculate and analysisthe ecological carrying capacity in Tibet. The results indicate: Tibet ecological footprint (2.1hm^2) keeps higher than countrywide average level (1.5 hm^2), and lower than global average level(2.4 hm^2); the result show that Tibet pasture ecological footprint is the most different with otherarea, and woodland is the second; Tibet ecological footprint grows from 1. 25 hm^2 in 1978 to 2.09hm^2 in 2002, which states that life level is improving continuously; GDP (per RMB 10~4 Yuan)ecological footprint reduces from 61. 9 hm^2 in 1978 to 4. 54 hm^2 in 2002, which states resourcesutilized ratio is increasing continuously.展开更多
As the research proposed reservoirs after impact on the surrounding ecological fragile areas of groundwater level and scope, through the proposed reservoir area and its surrounding data collecting, hydrogeology survey...As the research proposed reservoirs after impact on the surrounding ecological fragile areas of groundwater level and scope, through the proposed reservoir area and its surrounding data collecting, hydrogeology survey and related test, for Modflow system simulation platform, through to the boundary conditions, initial conditions and source sink term and related hydrogeological parameters, the model identification and verification, The model of hydrogeological parameters in the study area is constructed. The simulation results show that the groundwater depth near the reservoir area will be higher than the critical value (1.8 m) of secondary salinization of soil. At the same time, according to the investigation and experiment, if the reservoir does not do seepage treatment, the water infiltration in the reservoir will aggravate the environmental hydrogeological problems in the ecologically fragile area.展开更多
Using rural survey data for the year 2009,we provide evidence of work choices of rural laborers in ecologically vulnerable areas in North China,and model these choices as a function of characteristics of individuals,h...Using rural survey data for the year 2009,we provide evidence of work choices of rural laborers in ecologically vulnerable areas in North China,and model these choices as a function of characteristics of individuals,households,and land endowments.The findings reveal large differences between males and females,and between non-farm employment and part-time farming engagement Land scarcity is still an important driving factor in non-farming participation of rural laborers in the study area;and in the current case of land productivity and the total amount of land,there are still surplus rural labor forces in the study area.Diversification of livelihood reduces the pressure on land,thus facilitating ecosystem conservation.So,the paper concludes with the argument that establishing coordination mechanisms among non-farm employment of rural laborers,agricultural production,and restoration of ecosystems are essential for mitigating the conflicts of ecological security,agricultural production,and rural development in mis area.展开更多
The black rat is considered one of the world’s top pests.With increased restrictions on rodenticides,new alternatives to manage rats are urgently needed.Research on the use of contraceptive hormones,levonorgestrel(LE...The black rat is considered one of the world’s top pests.With increased restrictions on rodenticides,new alternatives to manage rats are urgently needed.Research on the use of contraceptive hormones,levonorgestrel(LE),and quinestrol(QU),have been evaluated against some rodent species,and this research is thefirst study to assess these on black rats.Hormones were incorporated into rodent bait at 10 and 50 ppm concentrations singly and in combination(EP-1).Groups of 10 animals of each sex were fed the baits over 7 days.Lower bait consumption was observed with slight body mass reductions.On dissection,it was observed that the uterus was in a state of edema and male reproductive organs weighed less with reduced sperm counts/motility.The 2 most promising baits,50 ppm QU and EP-1,were used to assess impact on pregnancy and litter size.Pregnancy was reduced from 70%success when both males and females consumed untreated bait,down to 30%when males had consumed contraceptive bait but females had not,and down to 0%when females had consumed contraceptive bait,regardless of whether they had paired with a treated or untreated male.Litter size in the untreated pairs was 8 pups,but only 4 pups in those cases where the male only had consumed the contraceptive.Further studies should investigate how long the effect lasts and its reversibility.Field studies at the population level may also shed light on the practicality of using contraceptive baits for black rats in different habitats.展开更多
The ricefield rat,Rattus argentiventer,is a significant pest of rice in Southeast Asia.Fertility control methods have the potential to provide safe and effective alternatives to control methods that often include indisc...The ricefield rat,Rattus argentiventer,is a significant pest of rice in Southeast Asia.Fertility control methods have the potential to provide safe and effective alternatives to control methods that often include indiscriminate use of rodenticides or electric barriers.The aim of this laboratory study was to assess uptake of bait coated with different concentrations of the contraceptive hormones,quinestrol(E)and levonorgestrel(P),delivered alone and in combination(i.e.EP-1)and determine the short-term effects on reproductive parameters of adult male and female R.argentiventer.In Experiment 1,2 concentrations of E,P,and EP-1(10,20 ppm)were fed to groups of wild-caught rats for 7 days.In females,both E and EP-1 induced uterine edema.In males,EP-1 reduced epididymis and seminal vesicle weights and lowered sperm motility.However,these responses were inconsistent due to low bait acceptance,especially with increasing concentrations.In Experiment 2,EP-1(0,20,50,100 ppm)was administered by oral gavage daily for 7 days to male R.argentiventer.There were significant reductions in epididymal and seminal vesicle weights for all oral doses of EP-1,in sperm counts for the 50 ppm dose,and in sperm motility for the 20 and 50 ppm doses compared to the control group.To select the optimum dose of EP-1,we must address the poor acceptance of contraceptive-coated baits by ricefield rats.Further research is required to improve the palatability of EP-1 and to test its uptake underfield conditions.展开更多
Ecology-oriented poverty alleviation is not only a livelihood project that affects the vast majority of rural people but also a major project to win the fight against poverty. It is also an indispensable income compon...Ecology-oriented poverty alleviation is not only a livelihood project that affects the vast majority of rural people but also a major project to win the fight against poverty. It is also an indispensable income component for the relocation of poor farmers. Dongchuan District,located at the intersection of Jinsha River and Xiaojiang River,is one of the key counties for poverty alleviation and development in China with a wide range of poverty and extreme poverty. The incidence of poverty reached 24. 36%. The ecology is fragile,and earthquake outbreaks frequently. Dongchuan District is a national key monitoring and defense area for earthquakes. A large number of goafs,subsidence areas and geological hazard areas have been formed in the mining area. The number of dangerous houses is large,and ' it has no way of supporting its own inhabitants' is the key point,difficulty and focus of the county’s poverty alleviation. Relocation is a must-have measure to move away from poverty. It is also complex system engineering,which is policy-oriented and difficult. Since 2017,Dongchuan District has regarded relocation has the top priority for poverty alleviation. It has strictly implemented national,provincial and municipal policies,focused on the overall goal of ' moving,securing and getting rich',and strongly promoted the relocation work for poverty alleviation. Obvious social,economic and ecological benefits have been achieved. Successful relocation,combined with ecology-oriented poverty alleviation and other targeted poverty alleviation measures,Dongchuan District’s fight against poverty has achieved a decisive victory. At the end of December 2018,the incidence of poverty in the region fell to 1. 09%,and 129 poor villages( including 86 extremely poor villages) had been successfully lifted out of poverty. This paper analyzes and condenses the specific practices,main achievements,benefits,successful experiences and implications of the region’s relocation combined with ecology-oriented poverty alleviation model,so as to pr展开更多
This study aims to implement the empirical analysis of the effects of the adaptive measures on the income of herdsmen in the context of the climate change with the positive mathematical programming(PMP)model.The surve...This study aims to implement the empirical analysis of the effects of the adaptive measures on the income of herdsmen in the context of the climate change with the positive mathematical programming(PMP)model.The survey was first implemented in three counties in the Three Headwaters Region.Finally the measures and recommendations suitable for the economic development in the ecologically fragile areas were proposed.The main conclusions are as follows:priority can be given to the measures to prevent the damage from rats and the engineering measures for pasture maintenance in Zeku County,where the geological conditions and grass quality are inferior,while the fiscal subsidy can be prioritized in Tongde County where the grassland area is relatively less.These recommendations can not only provide good reference for the protection of grassland resources,but they also lay a foundation for the implementation of more suitable measures to help the herdsmen in the ecologically fragile areas to adapt to the climate change.展开更多
Through the study of mutual process between groundwater systems and eco-environmental water demand, the eco-environmental water demand is brought into groundwater systems model as the important water consumption item ...Through the study of mutual process between groundwater systems and eco-environmental water demand, the eco-environmental water demand is brought into groundwater systems model as the important water consumption item and unification of groundwater抯 economic, environmental and ecological functions were taken into account. Based on eco-environmental water demand at Da抋n in Jilin province, a three-dimensional simulation and optimized management model of groundwater systems was established. All water balance components of groundwater systems in 1998 and 1999 were simulated with this model and the best optimal exploitation scheme of groundwater systems in 2000 was determined, so that groundwater resource was efficiently utilized and good economic, ecologic and social benefits were obtained.展开更多
As a result of rapid urbanization in China, urban sprawl has increased rapidly, and land-use regulation and smart urban growth are equally important. Spatial function regionalization can provide the scientific groundw...As a result of rapid urbanization in China, urban sprawl has increased rapidly, and land-use regulation and smart urban growth are equally important. Spatial function regionalization can provide the scientific groundwork for the regulation of land use and protection. This paper probes the system of evaluation indices and applies the methods of spatial analysis and classification clustering to the calculation of the ecologically significant value and economically significant value in each evaluation unit. After use of a classification matrix integrated by the two significant values, city space can be divided into four functional types, namely, feasible development area, moderate development area, moderate conservation area and prohibited exploiting area, and these are the basis for spatial development and control.展开更多
The paper had analyzed the necessity and feasibility for the protection and utilization of urban ecologically sensitive areas, proposed planning urban ecologically sensitive areas reasonably and combining ecological p...The paper had analyzed the necessity and feasibility for the protection and utilization of urban ecologically sensitive areas, proposed planning urban ecologically sensitive areas reasonably and combining ecological protection with development construction. Guiding the healthy and ordered development of urban spaces was the key part and important approach to realize ecological cities. The guiding thought for development construction of ecological cities had been discussed, which was conducting laddered development according to the location and coverage of urban ecologically sensitive areas and protection grades of these sensitive areas. Then, it had proposed four kinds of protection and construction modes, which were tourism leisure green lands, relevant expositions, industrial areas and new city groups, and which had been analyzed by combining with successful cases, so as to provide feasible win-win development strategies of ecology and economy for the planning of urban ecologically sensitive areas in the future.展开更多
基金Key Basic Science and Cutting Edge Technology Research Plan of Chongqing,No.cstc2015jcyjB0439Chongqing University Innovation Team for 2016,No.CXTDX201601017+1 种基金National Natural Science Foundation of China,No.41661020Chongqing Research Program of Basic Research and Frontier Technology,No.cstc2018jcyjAX0539。
文摘The Three Gorges Reservoir Area(TGRA)is typical of an ecologically vulnerable area,comprised of rural and mountainous areas,and with high immigration.Because of its economic and ecologic importance,studying the traditional agroecosystem changes in the TGRA is key to rural development and revitalization.In this study,we apply a framework of theoretical analysis,empirical study,and trend prediction to the Caotangxi River watershed within the TGRA.Using QuickBird high-resolution remote sensing images from 2012 to 2017 to evaluate natural resources and farmers’behavior,we analyze the transition and trends in the traditional agroecosystem in mountainous areas of the TGRA at spatial scale of the man-land relationship.We find that the agroecosystem in the TGRA can be divided into four modes using 100 m interval buffer rings:high-low-low,high-low-high,low-high-low and low-low-high mode where the different modes represent the agricultural development stages in the TGRA.Furthermore,the traditional agroecosystem in TGRA,represented by system elements such as farmers and sloping farmland,is transforming to accommodate the diversification of farmer livelihoods.For example,sloping farmland,which was dominated by a production function,now has equal emphasis on ecological and economic functions.Spatially,the range of the agroecosystem transition has migrated beyond high mountain areas to flat valley areas.Generally,this study provides an overview of land use in rural areas,controls on soil and water loss in mountainous areas,and better rural living environments in the TGRA.
基金supported by the National Key Research and Development Program of China(2021YFC2902004)the National Natural Science Foundation of China(42072284,42027801,and 41877186).
文摘A substantial reduction in groundwater level,exacerbated by coal mining activities,is intensifying water scarcity in western China’s ecologically fragile coal mining areas.China’s national strategic goal of achieving a carbon peak and carbon neutrality has made eco-friendly mining that prioritizes the protection and efficient use of water resources essential.Based on the resource characteristics of mine water and heat hazards,an intensive coal-water-thermal collaborative co-mining paradigm for the duration of the mining process is proposed.An integrated system for the production,supply,and storage of mining companion resources is achieved through technologies such as roof water inrush prevention and control,hydrothermal quality improvement,and deep-injection geological storage.An active preventive and control system achieved by adjusting the mining technology and a passive system centered on multiobjective drainage and grouting treatment are suggested,in accordance with the original geological characteristics and dynamic process of water inrush.By implementing advanced multi-objective drainage,specifically designed to address the“skylight-type”water inrush mode in the Yulin mining area of Shaanxi Province,a substantial reduction of 50%in water drillings and inflow was achieved,leading to stabilized water conditions that effectively ensure subsequent safe coal mining.An integrated-energy complementary model that incorporates the clean production concept of heat utilization is also proposed.The findings indicate a potential saving of 8419 t of standard coal by using water and air heat as an alternative heating source for the Xiaojihan coalmine,resulting in an impressive energy conservation of 50.2%and a notable 24.2%reduction in carbon emissions.The ultra-deep sustained water injection of 100 m^(3)·h^(-1)in a single well would not rupture the formation or cause water leakage,and 7.87×10^(5)t of mine water could be effectively stored in the Liujiagou Formation,presenting a viable method for mine-water mana
基金Supported by Central Public-interest Scientific Institution Basal Research Fund of China(BRF090202)~~
文摘Guazhou County of Gansu Province is a typical ecological fragile area lying in the transition area of desert and oasis.The development of its agricultural economy is highly dependent on natural resources and environment.Contradiction of resources characterized agriculture and the fragile ecological environment has become one of the main barriers to log the impact of local agriculture to achieve sustainable development.Aiming at fragile ecological environment and limiting factors of agricultural sustainable development,thoughts and countermeasures of realizing agricultural sustainable development have been proposed.
基金This study was jointly supported by the National Key Research and Development Program of China （2016YFC0402208, 2016YFC0401903, and 2016YFC0400903）, the National Natural Science Foundation of China （51709276）, and the State Key Laboratory of Simulation and Regulation of the Water Cycle in River Basins （2016CG05）.
文摘Constructing and operating a multi-reservoir system changes the natural flow regime of rivers, and thus imposes adverse impacts on riverine ecosystems. To balance human needs with ecosystem needs, this study proposes an ecologically oriented operation strategy for a multi-reservoir system that integrates environmental flow requirements into the joint operation of a multi-reservoir system in order to main- tain different ecological functions throughout the river. This strategy is a combination of a regular opti-mal operation scheme and a series of real-time ecological operation schemes. During time periods when the incompatibilities between human water needs and ecosystem needs for environmental flows are rel- atively small, the regular optimal operation scheme is implemented in order to maximize multiple human water-use benefits under the constraints of a minimum water-release policy. During time periods when reservoir-induced hydrological alteration imposes significant negative impacts on the river＇s key ecological functions, real-time ecological operation schemes are implemented in order to modify the out- flow from reservoirs to meet the environmental flow requirements of these functions. The practical use of this strategy is demonstrated for the simulation operation of a large-scale multi-reservoir system which located in the middle and lower Han River Basin in China. The results indicate that the real-time ecological operation schemes ensure the environmental flow requirements of the river＇s key ecological functions, and that adverse impacts on human water-use benefits can be compensated for by the regular optimal operation scheme. The ecologically oriented operation strategy for a multi-reservoir system that is proposed in this study enriches the theoretical application of the multi-reservoir system joint operation which considers environmental flow requirements.
基金the auspices of the National Natural Science Foundation of China(No.41571152,41771179)the Social Science Foundation of Jilin Province,China(No.2019B56)。
文摘Following the trends of Chinese rural transformation development, and the sustainable development goals for resources and environment, reasonable arranging the potential development space and the ecological space, so as to optimize the distributions of rural settlement would be the key challenge for rural areas in ecologically fragile regions. From the perspective of maintaining regional ecological security, this paper takes Da’an City, a typical ecological fragile region in Jilin Province, as the case area, constructing the comprehensive ecological security pattern(ESP) on basis of landscape ecology, and applying the landscape pattern indexes to quantitative analysis the spatial distribution characteristics of rural settlements. Then, different optimization directions and management strategies are put forward for rural settlements in each secure zone under the comprehensive ESP. The experimental results showed that 1) the area of the low security zone, the general security zone, the moderate security zone and the extreme security zone was 1570.18 km^2, 1463.36 km^2, 1215.80 km^2 and 629.77 km^2, representing 32.18%, 29.99%, 24.92% and 12.91% of the total area of the target area, respectively. 2) The rural settlements in Da’an City were characterized by a high degree of fragmentation with a large number of small-scale patches. 3) The area of rural settlements in the ecological relocation zone, the in situ remediation zone, the limited development zone and the key development zone was 22.80 km^2, 42.31 km^2, 36.28 km^2 and 19.40 km^2, accounting for 18.88%, 35.03%, 30.04% and 16.06% of the total area of rural settlements, respectively. Then, different measures were proposed for settlements in different optimization zones in order to scientifically plan important ecological space, production space and living space in rural areas. This paper aims to provide fundamental support for rural settlements based on redistribution from the perspective of landscape ecology and provide insights for rural planning and rural
基金supported by grants from the Key Research Program of Frontier Sciences,CAS(QYZDJSSW-DQC027)National Natural Science Foundation of China(31770757,31770758)+1 种基金the Consultation Project supported by Divisions of the Chinese Academy of Sciences(2019-ZW09-A-032)“Research on Development of Key Subjects in 2020−2021”from Ecological Society of China.
文摘A protective forest,including shelterbelt,windbreak,and shelter forest as its synonyms,is characterized by the protective functions of various forest types distributed or planted on ecologically fragile areas or nearby the objects that need to be protected using the ecological effects of forests.Ecological mechanisms for management practices of protective forests is one of the disciplinary orientations in forest ecology and management.Most protective forest studies are dependent on forestry eco-engineering,such as the Great Plains Shelterbelt Project in the United States,the Great Plan for the Transformation of Nature in the Soviet Union,and the Three-North Afforestation Program in China.The development of sustainable management of protective forests has been given increasing attention by governments,scientists,and media due to their impacts on environment conservation and global change.We introduce forestry ecoengineering and provide a review of their main ecological mechanisms for management practices of protective forests.Ecological mechanisms for management systems currently applied are emphasized,i.e.,the theory of protection maturity and phase-directional management;the relationship between structure and protective functions and structural optimization measures;and,the decline mechanism and ecological restoration strategies.In addition,several unresolved problems in management practices of protective forests are discussed as well as the prospects for ecological mechanisms for management practices of protective forests in the future,which include:(1)theories and technologies for management practices of protective forests at the landscape or regional scale;(2)the decline mechanisms and corresponding ecological restoration approaches across multiple scales;and,(3)the comprehensive assessment of forestry eco-engineering at large-scales based on ecosystem principles.
基金funded by the Department of Science and Technology of Zhejiang Province in China(“Pioneer”and“Bellwethers”R&D Projects,No.2022C03119)the Environmental Defense Fund(Nos.EDF-B-5282019 and 20220023).
文摘Synergetic energy-water-carbon pathways are key issues to be tackled under carbon-neutral target and high-quality development worldwide,especially in ecologically vulnerable regions(EVRs).In this study,to explore the synergistic pathways in an EVR,a water-energy-carbon assessment(WECA)model was built,and the synergistic effects of water-energy-carbon were comprehensively and quantitatively analyzed under various scenarios of regional transition.Shaanxi Province was chosen as the representative EVR,and Lower challenge(LEC)and Greater challenge(GER)scenarios of zerocarbon transition were set considering the technological maturity and regional energy characteristics.The results showed that there were limited effects under the zero-carbon transition of the entire region on reducing water withdrawals and improving the water quality.In the LEC scenario,the energy demand and CO_(2) emissions of Shaanxi in 2060 will decrease by 70.9%and 99.4%,respectively,whereas the water withdrawal and freshwater aquatic ecotoxicity potential(FAETP)will only decrease by 8.9%and 1.6%,respectively.This could be attributed to the stronger demand for electricity in the energy demand sector caused by industrial transition measures.The GER scenario showed significant growth in water withdrawals(16.0%)and FAETP(36.0%)because of additional biomass demand.To promote the synergetic development of regional transition,EVRs should urgently promote zero-carbon technologies(especially solar and wind power technologies)between 2020 and 2060 and dry cooling technology for power generation before 2030.In particular,a cautious attitude toward the biomass energy with carbon capture and storage technology in EVRs is strongly recommended.
基金funded by the German Federal Ministry of Food and Agriculture due to a parliamentary resolution within the federal program“Organic farming and other forms of sustainable agriculture”(grant#2815NA113)the External Cooperation Program,Chinese Academy of Sciences(grant#152111KYSB20150023,GJHZ1797).
文摘Management of overabundant rodents at a landscape scale is complex but often required to sustainably reduce rodent abundance below damage thresholds.Current conventional techniques such as poisoning are not species specific,with some approaches becoming increasingly unacceptable to the general public.Fertility control,first proposed for vertebrate pest management over 5 decades ago,has gained public acceptance because it is perceived as a potentially more species-specific and humane approach compared with many lethal methods.An ideal fertility control agent needs to induce infertility across one or more breeding seasons,be easily delivered to an appro-priate proportion of the population,be species specific with minimal side-effects(behavioral or social structure changes),and be environmentally benign and cost effective.To date,effective fertility control of rodents has not been demonstrated at landscape scales and very few products have achieved registration.Reproductive targets for fertility control include disrupting the hormonal feedback associated with the hypothalamic-pituitary-gonadal axis,gonad function,fertilization,and/or early implantation.We review progress on the oral delivery of various agents for which laboratory studies have demonstrated efficacy in females and/or males and synthesize progress with the development and/or use of synthetic steroids,plant extracts,ovarian specific peptides,and immunocontracep-tive vaccines.There are promising results forfield application of synthetic steroids(levonorgestrel,quinestrol),chemosterilants(4-vinylcyclohexene diepoxide),and some plant extracts(triptolide).For most fertility control agents,more research is essential to enable their efficient and cost-effective delivery such that rodent impacts at a population level are mitigated and food security is improved.
基金Supported by the Guangxi Zhuang Autonomous Region (GZAR) Science and Technology Project (AB20159022 and AB17292051)GZAR Natural Science Foundation (2018GXNSFAA281338)。
文摘Meteorological conditions have an important impact on changes of vegetation in ecologically fragile karst areas.This study aims to explore a method for quantitative evaluation of these meteorological conditions. We analyzed the changing trend of vegetation during 2000–2018 and the correlations between vegetation changes and various meteorological factors in karst rocky areas of Guangxi Zhuang Autonomous Region, China. Key meteorological factors in vegetation areas with varying degrees of improvement were selected and evaluated at seasonal timescale. A quantitative evaluation model of comprehensive influences of meteorological factors on vegetation was built by using the partial least-square regression(PLS). About 91.45% of the vegetation tended to be improved, while only the rest 8.55% showed a trend of degradation from 2000 to 2018. Areas with evident vegetation improvement were mainly distributed in the middle and northeast, and those with obvious vegetation degradation were scattered. Meteorological factors affecting vegetation were significantly different among the four seasons. Overall, high air humidity, small temperature difference in spring and autumn, and low daily minimum temperature and air pressure were favorable conditions. Low temperature in winter as well as high temperature in summer and autumn were unfavorable conditions. The Climate Vegetation Index(CVI) model was established by PLS using the maximum, minimum, and average temperatures;vapor pressure;rainfall;and air pressure as key meteorological factors. The Enhanced Vegetation Index(EVI) was well fitted by the CVI model, with the average coefficient of determination(r2) and root mean square error(RMSE) of 0.856 and 0.042, respectively. Finally, an assessment model of comprehensive meteorological conditions was built based on the interannual differences in CVI. The meteorological conditions in the study area in 2014 were successfully evaluated by combining the model and selected seasonal key meteorological factors.
文摘Ecological footprint's theory and method are used to calculate and analysisthe ecological carrying capacity in Tibet. The results indicate: Tibet ecological footprint (2.1hm^2) keeps higher than countrywide average level (1.5 hm^2), and lower than global average level(2.4 hm^2); the result show that Tibet pasture ecological footprint is the most different with otherarea, and woodland is the second; Tibet ecological footprint grows from 1. 25 hm^2 in 1978 to 2.09hm^2 in 2002, which states that life level is improving continuously; GDP (per RMB 10~4 Yuan)ecological footprint reduces from 61. 9 hm^2 in 1978 to 4. 54 hm^2 in 2002, which states resourcesutilized ratio is increasing continuously.
文摘As the research proposed reservoirs after impact on the surrounding ecological fragile areas of groundwater level and scope, through the proposed reservoir area and its surrounding data collecting, hydrogeology survey and related test, for Modflow system simulation platform, through to the boundary conditions, initial conditions and source sink term and related hydrogeological parameters, the model identification and verification, The model of hydrogeological parameters in the study area is constructed. The simulation results show that the groundwater depth near the reservoir area will be higher than the critical value (1.8 m) of secondary salinization of soil. At the same time, according to the investigation and experiment, if the reservoir does not do seepage treatment, the water infiltration in the reservoir will aggravate the environmental hydrogeological problems in the ecologically fragile area.
基金support from the National Natural Science Foundation of China[grant number 40971062]
文摘Using rural survey data for the year 2009,we provide evidence of work choices of rural laborers in ecologically vulnerable areas in North China,and model these choices as a function of characteristics of individuals,households,and land endowments.The findings reveal large differences between males and females,and between non-farm employment and part-time farming engagement Land scarcity is still an important driving factor in non-farming participation of rural laborers in the study area;and in the current case of land productivity and the total amount of land,there are still surplus rural labor forces in the study area.Diversification of livelihood reduces the pressure on land,thus facilitating ecosystem conservation.So,the paper concludes with the argument that establishing coordination mechanisms among non-farm employment of rural laborers,agricultural production,and restoration of ecosystems are essential for mitigating the conflicts of ecological security,agricultural production,and rural development in mis area.
基金funded by the African Union/European Development Fund(EcoRodMan:AURGII/1/006/2016)support from the International Partnership Programme of the Chinese Academy of Sciences(Grant No.152111KYSB20160089)。
文摘The black rat is considered one of the world’s top pests.With increased restrictions on rodenticides,new alternatives to manage rats are urgently needed.Research on the use of contraceptive hormones,levonorgestrel(LE),and quinestrol(QU),have been evaluated against some rodent species,and this research is thefirst study to assess these on black rats.Hormones were incorporated into rodent bait at 10 and 50 ppm concentrations singly and in combination(EP-1).Groups of 10 animals of each sex were fed the baits over 7 days.Lower bait consumption was observed with slight body mass reductions.On dissection,it was observed that the uterus was in a state of edema and male reproductive organs weighed less with reduced sperm counts/motility.The 2 most promising baits,50 ppm QU and EP-1,were used to assess impact on pregnancy and litter size.Pregnancy was reduced from 70%success when both males and females consumed untreated bait,down to 30%when males had consumed contraceptive bait but females had not,and down to 0%when females had consumed contraceptive bait,regardless of whether they had paired with a treated or untreated male.Litter size in the untreated pairs was 8 pups,but only 4 pups in those cases where the male only had consumed the contraceptive.Further studies should investigate how long the effect lasts and its reversibility.Field studies at the population level may also shed light on the practicality of using contraceptive baits for black rats in different habitats.
基金All experiments followed the guidelines of the American Society of Mammalogists(Sikes et al.2016)The protocol and procedures employed were ethically reviewed and approved by the Institute of Zoology(IOZ-IACUC-2021-093)The study was supported by the International Partnership Program of Chinese Academy of Sciences,Grant No.152111KYSB20160089.
文摘The ricefield rat,Rattus argentiventer,is a significant pest of rice in Southeast Asia.Fertility control methods have the potential to provide safe and effective alternatives to control methods that often include indiscriminate use of rodenticides or electric barriers.The aim of this laboratory study was to assess uptake of bait coated with different concentrations of the contraceptive hormones,quinestrol(E)and levonorgestrel(P),delivered alone and in combination(i.e.EP-1)and determine the short-term effects on reproductive parameters of adult male and female R.argentiventer.In Experiment 1,2 concentrations of E,P,and EP-1(10,20 ppm)were fed to groups of wild-caught rats for 7 days.In females,both E and EP-1 induced uterine edema.In males,EP-1 reduced epididymis and seminal vesicle weights and lowered sperm motility.However,these responses were inconsistent due to low bait acceptance,especially with increasing concentrations.In Experiment 2,EP-1(0,20,50,100 ppm)was administered by oral gavage daily for 7 days to male R.argentiventer.There were significant reductions in epididymal and seminal vesicle weights for all oral doses of EP-1,in sperm counts for the 50 ppm dose,and in sperm motility for the 20 and 50 ppm doses compared to the control group.To select the optimum dose of EP-1,we must address the poor acceptance of contraceptive-coated baits by ricefield rats.Further research is required to improve the palatability of EP-1 and to test its uptake underfield conditions.
基金Supported by Commissioned Project of Office of Rural Work Leading Group of Kunming Municipal Committee of the Communist Party of China"Study on the Poverty Alleviation Model of Kunming City in the Context of World Poverty Reduction"
文摘Ecology-oriented poverty alleviation is not only a livelihood project that affects the vast majority of rural people but also a major project to win the fight against poverty. It is also an indispensable income component for the relocation of poor farmers. Dongchuan District,located at the intersection of Jinsha River and Xiaojiang River,is one of the key counties for poverty alleviation and development in China with a wide range of poverty and extreme poverty. The incidence of poverty reached 24. 36%. The ecology is fragile,and earthquake outbreaks frequently. Dongchuan District is a national key monitoring and defense area for earthquakes. A large number of goafs,subsidence areas and geological hazard areas have been formed in the mining area. The number of dangerous houses is large,and ' it has no way of supporting its own inhabitants' is the key point,difficulty and focus of the county’s poverty alleviation. Relocation is a must-have measure to move away from poverty. It is also complex system engineering,which is policy-oriented and difficult. Since 2017,Dongchuan District has regarded relocation has the top priority for poverty alleviation. It has strictly implemented national,provincial and municipal policies,focused on the overall goal of ' moving,securing and getting rich',and strongly promoted the relocation work for poverty alleviation. Obvious social,economic and ecological benefits have been achieved. Successful relocation,combined with ecology-oriented poverty alleviation and other targeted poverty alleviation measures,Dongchuan District’s fight against poverty has achieved a decisive victory. At the end of December 2018,the incidence of poverty in the region fell to 1. 09%,and 129 poor villages( including 86 extremely poor villages) had been successfully lifted out of poverty. This paper analyzes and condenses the specific practices,main achievements,benefits,successful experiences and implications of the region’s relocation combined with ecology-oriented poverty alleviation model,so as to pr
基金financially supported by the"Strategy and Policies on Environment and Development in Western China" project of "China Council for International Cooperation on Environment and Development(CCICED)"
文摘This study aims to implement the empirical analysis of the effects of the adaptive measures on the income of herdsmen in the context of the climate change with the positive mathematical programming(PMP)model.The survey was first implemented in three counties in the Three Headwaters Region.Finally the measures and recommendations suitable for the economic development in the ecologically fragile areas were proposed.The main conclusions are as follows:priority can be given to the measures to prevent the damage from rats and the engineering measures for pasture maintenance in Zeku County,where the geological conditions and grass quality are inferior,while the fiscal subsidy can be prioritized in Tongde County where the grassland area is relatively less.These recommendations can not only provide good reference for the protection of grassland resources,but they also lay a foundation for the implementation of more suitable measures to help the herdsmen in the ecologically fragile areas to adapt to the climate change.
基金The Key Project of the National Ninth-Five-Year Plan No. 96-004-02-09The 48Project of Ministry of Water Resources No. 985106The Project of Chinese Academy of Sciences
文摘Through the study of mutual process between groundwater systems and eco-environmental water demand, the eco-environmental water demand is brought into groundwater systems model as the important water consumption item and unification of groundwater抯 economic, environmental and ecological functions were taken into account. Based on eco-environmental water demand at Da抋n in Jilin province, a three-dimensional simulation and optimized management model of groundwater systems was established. All water balance components of groundwater systems in 1998 and 1999 were simulated with this model and the best optimal exploitation scheme of groundwater systems in 2000 was determined, so that groundwater resource was efficiently utilized and good economic, ecologic and social benefits were obtained.
基金Under the auspices of the National Science Foundation of China(No.41871119,41871209)
文摘As a result of rapid urbanization in China, urban sprawl has increased rapidly, and land-use regulation and smart urban growth are equally important. Spatial function regionalization can provide the scientific groundwork for the regulation of land use and protection. This paper probes the system of evaluation indices and applies the methods of spatial analysis and classification clustering to the calculation of the ecologically significant value and economically significant value in each evaluation unit. After use of a classification matrix integrated by the two significant values, city space can be divided into four functional types, namely, feasible development area, moderate development area, moderate conservation area and prohibited exploiting area, and these are the basis for spatial development and control.
文摘The paper had analyzed the necessity and feasibility for the protection and utilization of urban ecologically sensitive areas, proposed planning urban ecologically sensitive areas reasonably and combining ecological protection with development construction. Guiding the healthy and ordered development of urban spaces was the key part and important approach to realize ecological cities. The guiding thought for development construction of ecological cities had been discussed, which was conducting laddered development according to the location and coverage of urban ecologically sensitive areas and protection grades of these sensitive areas. Then, it had proposed four kinds of protection and construction modes, which were tourism leisure green lands, relevant expositions, industrial areas and new city groups, and which had been analyzed by combining with successful cases, so as to provide feasible win-win development strategies of ecology and economy for the planning of urban ecologically sensitive areas in the future.
