A new monitoring index for ecological vulnerability and its application in the Yellow River Basin,China from 2000 to 2022

The ecological environment of the Yellow River Basin has become more fragile under the combined action of natural and manmade activities.However,the change mechanisms of ecological vulnerability in different sub-regions and periods vary,and the reasons for this variability are yet to be explained.Thus,in this study,we proposed a new remote sensing ecological vulnerability index by considering moisture,heat,greenness,dryness,land degradation,and social economy indicators and then analyzed and disclosed the spatial and temporal change patterns of ecological vulnerability of the Yellow River Basin,China from 2000 to 2022 and its driving mechanisms.The results showed that the newly proposed remote sensing ecological vulnerability index had a high accuracy,at 86.36%,which indicated a higher applicability in the Yellow River Basin.From 2000 to 2022,the average remote sensing ecological vulnerability index of the Yellow River Basin was 1.03,denoting moderate vulnerability level.The intensive vulnerability area was the most widely distributed,which was mostly located in the northern part of Shaanxi Province and the eastern part of Shanxi Province.From 2000 to 2022,the ecological vulnerability in the Yellow showed an overall stable trend,while that of the central and eastern regions showed an obvious trend of improvement.The gravity center of ecological vulnerability migrated southwest,indicating that the aggravation of ecological vulnerability in the southwestern regions was more severe than in the northeastern regions of the basin.The dominant single factor of changes in ecological vulnerability shifted from normalized difference vegetation index(NDVI)to temperature from 2000 to 2022,and the interaction factors shifted from temperature∩NDVI to temperature∩precipitation,which indicated that the global climate change exerted a more significant impact on regional ecosystems.The above results could provide decision support for the ecological protection and restoration of the Yellow River Basin.

APPLICATION OF ANALYTIC HIERARCHY PROCESS TO ASSESSING THE ECOLOGICAL VULNERABILITY OF WETLANDS IN THE JIANGHAN PLAIN

Wetlands in the Jianghan Plain are important components of wetland types in lake area in the middle and lower reaches the Changjiang (Yangtze) River and they fulfill many uses and functions related to hydrology, waste assimilation, ecosystem productivity and biodiversity. Owing to natural factors and human activities, especially excessive reclamation from lakes, the shrinking process of the lakes has been accelerated. Wetland ecosystem has shown the characteristics of vulnerability. According to the analysis of wetland ecological function in the Jianghan Plain, this paper presented an index system related to productivity, stability and environmental capacity. By using the method of Analytic Hierarchy Process, we computed the values of the relative weights of the indexes, and evaluated the vulnerability level of the wetland ecosystem by the method of multi-indexes. The case study showed that the fragile extent of wetland ecosystem in the Jianghan Plain is 5.6. This means that the wetland ecosystem in the Jianghan Plain is laid to the state of middle vulnerability. Therefore, the wetland conservation and eco-rehabilitation in the Jianghan Plain should be paid attention to.

Spatial-temporal variations of ecological vulnerability in the Tarim River Basin,Northwest China

As the largest inland river basin of China,the Tarim River Basin(TRB),known for its various natural resources and fragile environment,has an increased risk of ecological crisis due to the intensive exploitation and utilization of water and land resources.Since the Ecological Water Diversion Project(EWDP),which was implemented in 2001 to save endangered desert vegetation,there has been growing evidence of ecological improvement in local regions,but few studies have performed a comprehensive ecological vulnerability assessment of the whole TRB.This study established an evaluation framework integrating the analytic hierarchy process(AHP)and entropy method to estimate the ecological vulnerability of the TRB covering climatic,ecological,and socioeconomic indicators during 2000-2017.Based on the geographical detector model,the importance of ten driving factors on the spatial-temporal variations of ecological vulnerability was explored.The results showed that the ecosystem of the TRB was fragile,with more than half of the area(57.27%)dominated by very heavy and heavy grades of ecological vulnerability,and 28.40%of the area had potential and light grades of ecological vulnerability.The light grade of ecological vulnerability was distributed in the northern regions(Aksu River and Weigan River catchments)and western regions(Kashgar River and Yarkant River catchments),while the heavy grade was located in the southern regions(Kunlun Mountains and Qarqan River catchments)and the Mainstream catchment.The ecosystems in the western and northern regions were less vulnerable than those in the southern and eastern regions.From 2000 to 2017,the overall improvement in ecological vulnerability in the whole TRB showed that the areas with great ecological improvement increased by 46.11%,while the areas with ecological degradation decreased by 9.64%.The vegetation cover and potential evapotranspiration(PET)were the obvious driving factors,explaining 57.56% and 21.55%of the changes in ecological vulnerability across the TRB,respectively.In terms of ecological vulnerability grade changes,obvious spatial differences were observed in the upper,middle,and lower reaches of the TRB due to the different vegetation and hydrothermal conditions.The alpine source region of the TRB showed obvious ecological improvement due to increased precipitation and temperature,but the alpine meadow of the Kaidu River catchment in the Middle Tianshan Mountains experienced degradation associated with overgrazing and local drought.The improved agricultural management technologies had positive effects on farmland ecological improvement,while the desert vegetation in oasis-desert ecotones showed a decreasing trend as a result of cropland reclamation and intensive drought.The desert riparian vegetation in the lower reaches of the Tarim River was greatly improved due to the implementation of the EWDP,which has been active for tens of years.These results provide comprehensive knowledge about ecological processes and mechanisms in the whole TRB and help to develop environmental restoration measures based on different ecological vulnerability grades in each sub-catchment.

Spatiotemporal Evolution and Influencing Factors of Landscape Ecological Vulnerability in the Three-River-Source National Park Region

The increasing impact of global warming and human activities has exacerbated the ecological environment in the Three-RiverSource National Park Region(TNPR). Understanding the temporal and spatial evolution of landscape ecological vulnerability(LEV)and its influencing factors are crucial to the implementation of environmental management. Here, we aimed to: 1) construct a LEV assessment model integrating landscape structure and function;2) analyze the temporal and spatial evolution of TNPR’s LEV from 1995to 2015;3) use geographic detectors to reveal the regional influence factors of TNPR’s LEV. The main findings were: 1) grasslands, water, and bare land are important landscapes of TNPR, accounting for 98.37% of the total area. During the study period, there were significant differences in the area of different landscapes;except for desert, shrub, and urban land, the other landscape areas showed a decreasing trend. 2) During the study period, the LEV of TNPR showed a downward trend;except for grasslands, the ecological vulnerability of the other landscapes decreased steadily. Furthermore, a pattern of conversion from high to low vulnerability grade was observed in the study area. In terms of spatial distribution, the LEV level shows a trend of high at both ends(east and west) and low in the middle.3) Overall, the impact of natural factors on the ecological vulnerability of the TNPR was significantly higher than that of human factors.In conclusion, our study provides a scientific basis for landscape structure optimization and the management of regional ecological vulnerability.

Dynamic Assessment on Ecosystem Vulnerability in Dashanbao Wetland

[Objective] The aim was to assess the ecosystem vulnerability of Dashanbao wetland.[Method] The evaluation index system of ecosystem vulnerability of Dashanbao wetland was constructed by using analytic hierarchy process(AHP),and the ecosystem vulnerability of Dashanbao wetland from 2002 to 2008 was assessed based on vulnerable degree of ecosystem.[Result] The vulnerable degree of ecosystem of Dashanbao wetland from 2002 to 2008 was 0.560 0,0.513 7,0.516 4,0.465 4,0.476 0,0.449 2 and 0.400 6 respectively,that is,showing decreasing trend on the whole,and the vulnerability of wetland ecosystem transformed from moderate vulnerability to mild vulnerability,and it showed that the ecological environment quality of Dashanbao wetland was better.[Conclusion] The study could provide references for wetland restoration,protection,ecological environment planning and management.

EVOLVEMENT AND CONTROL OF VULNERABLE ECOLOGICAL REGION—A Case Study in Ongniud Banner and Aohan Banner,Inner Mongolia

The evolvement of a vulnerable ecological region is a dynamic process, which is affected by various factors. During the evolvement process, human activities have a decisive effect. The purpose of studying vulnerable ecological region is to control human economic activities and to develop a negative feedback modulation mechanism.This paper established a model of vulnerable ecological region's evolvement by considering four synthetic variables.These synthetic variables are ecological carrying capacity, ecological resilience, economic development intensity, and economic development velocity. Finally, Ongniud Banner and Aohan Banner in North China were taken as study cases to simulate the evolvement processes of vulnerable ecological regions under different conditions of economic development. The results show that human activities have an important influence on the evolvement trend of vulnerable ecological region.

Game Analysis and Mechanism Design of Ecological Protection Red Line for Ecologically Vulnerable Areas in Western China

Drawing the ecological protection red line is to maintain the integrity and benign operation of the ecosystem within the area,and to ensure that the ecological environment is within the boundary of controllable ecological security.Taking the ecologically vulnerable areas in western China as the research object and using the game theory and literature analysis,this paper studied the game behavior of ecological protection red line in these areas.In addition,this paper also analyzed the stakeholders such as government,enterprises and the masses in the drawing of the ecological protection red line,and comprehensively analyzed the game strategies between the government and the masses,the government and enterprises,and the central and local governments and enterprises.On the basis of the analysis,it came up with a safeguard mechanism for the coordination of the interests of the ecological protection red line.

Synergetic pathways of water-energy-carbon in ecologically vulnerable regions aiming for carbon neutrality:a case study of Shaanxi,China

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.

Regional Ecological Vulnerability Assessment of the Guangxi Xijiang River Economic Belt in Southwest China with VSD Model

The interactive effects of natural and human factors on ecosystems have been well studied, and the quantitative assessment of large-scale ecological vulnerability caused by natural and human factors is now one of the most active topics in the ifeld. Taking the Guangxi Xijiang River Economic Belt in southwest China （GXEB） as a case study, we assess ecological vulnerability based on the Vulnerability Scoping Diagram （VSD） model. The indices system is decomposed into three sub objects, ten elements and 25 indicators layer by layer, which included factors from both natural and human ifelds. Results indicate that zones with lower, middle-lower, middle, middle-higher and higher vulnerability account for 11.31%, 22.63%, 27.60%, 24.39%, and 14.07%, respectively. The western and eastern parts of GXEB are more vulnerable than the central part and the mountain and urban areas are of higher vulnerability than the basins and river valleys. Compared with a vulnerability assessment based on natural factors only, it is concluded that human activities indeed cause the transition from naturally stable zones to vulnerable zones. The nature-dominated vulnerable zones are different with human-dominated ones in size and distribution, the latter being smaller, more scattered and distributed in urban areas and their surroundings. About 53%of total construction land is distributed in zones with middle and middle-higher ecological vulnerability;less vulnerable zones should attract construction in the future. Relevant suggestions are proposed on how to reduce vulnerability according to inducing factors. The VSD model has a signiifcant advantage in the quantitative evaluation of ecological vulnerability, but is insufficient to distinguish nature- or human-dominated vulnerability quantitatively.

Assessing the ecological vulnerability of protected areas by using Big Earth Data

The ecological vulnerability of global protected areas(PAs)is linked to the 2030 United Nations Sustainable Development Goals.We developed a novel degree of ecological vulnerability(DEV)index based on Big Earth Data to assess the ecological vulnerability of PAs.This is a transparent,repeatable,large-scale and rapid assessment method.We applied the method to case studies of International Union for Conservation of Nature(IUCN)PAs in the basins of the Aral Sea,the Caspian Sea,the Black Sea and the Lake Baikal.Between 2001 and 2015,the spatial pattern of ecological vulnerability in the study area was relatively stable.The Caspian Sea basin and protected landscape/seascape(category V)showed high ecological vulnerability,while the Black Sea basin and wilderness areas(category Ib)showed low ecological vulnerability.Big Earth Data shows great vitality in PAs ecological vulnerability assessment.Strengthening international cooperation is an important means to break the bottleneck of ecological environment and resource endowment in these important international basins.

Variability in Regional Ecological Vulnerability: A Case Study of Sichuan Province, China

Rapid urbanization and natural hazards are posing threats to local ecological processes and ecosystem services worldwide.Using land use,socioeconomic,and natural hazards data,we conducted an assessment of the ecological vulnerability of prefectures in Sichuan Province for the years 2005,2010,and 2015 to capture variations in its capacity to modulate in response to disturbances and to explore potential factors driving these variations.We selected five landscape metrics and two topological indicators for the proposed ecological vulnerability index(EVI),and constructed the EVI using a principal component analysis-based entropy method.A series of correlation analyses were subsequently performed to identify the factors driving variations in ecological vulnerability.The results show that:(1)for each of the study years,prefectures with high ecological vulnerability were located mainly in southern and eastern Sichuan,whereas prefectures in central and western Sichuan were of relatively low ecological vulnerability;(2)Sichuan’s ecological vulnerability increased significantly(p=0.011)during2005–2010;(3)anthropogenic activities were the main factors driving variations in ecological vulnerability.These findings provide a scientific basis for implementing ecological protection and restoration in Sichuan as well as guidelines for achieving integrated disaster risk reduction.

A new perspective on ecological vulnerability and its transformation mechanisms

Ecological vulnerability refers to the degree of ecosystem disturbance,system damage,and the ability of system restoration.Although case-specific evaluations of ecological vulnerability are progressing rapidly,they have been carried out mainly in areas with intensive human activities or in harsh natural environments.Using the Web of ScienceTM core collection,this review paper summarized studies on ecological vulnerability published from 2000 to 2022 and analyzed in depth major case studies.It was found that traditional ecological vulnerability research has been addressed largely in terms of assessment models,data processing models,and analysis of influencing factors,however there was a lack of research on the process of vulnerability transformation.Because the vulnerability transformation in a hierarchical vulnerability index system is regulated by multiple factors in a heterogeneous region,it is urgent to understand how the ecological vulnerability in a region evolves from one level to another over time.Therefore this paper put forward the new perspective of research,i.e.,applying quantitative analysis to identification of regulating factors and exploring the mechanisms of ecological vulnerability transformation.This new perspective could assist in monitoring the complex spatiotemporal changes in ecological vulnerability and taking necessary measures to prevent from decline of ecological stability.

Quantitative Assessment of the Ecological Vulnerability of Baiyangdian Wetlands in the North China Plain

Quantitative assessment of vulnerability is a core aspect of wetland vulnerability research.Taking Baiyangdian(BYD)wetlands in the North China Plain as a study area and using the‘cause-result’model,23 representative indicators from natural,social,sci-tech and economic elements were selected to construct an indicator system.A weight matrix was obtained by using the entropy weight method to calculate the weight value for each indicator.Based on the membership function in the fuzzy evaluation model,the membership degrees were determined to form a fuzzy relation matrix.Finally,the ecological vulnerability was quantitatively assessed based on the comprehensive evaluation index calculated by using a composite operator to combine the entropy weight matrix with the fuzzy relation matrix.The results showed that the ecological vulnerability levels of the BYD wetlands were comprehensively evaluated as Grade Ⅱ,Grade Ⅲ,Grade Ⅳ,and Grade Ⅲ in 2010,2011-2013,2014,and 2015-2017,respectively.The ecological vulnerability of the BYD wetlands increased from low fragility in 2010 to general fragility in 2011-2013,and to high fragility in 2014,reflecting the fact that the wetland ecological condition was degenerating from 2010 to 2014.The ecological vulnerability status then turned back into general fragility during 2015-2017,indicating that the ecological situation of the BYD wetlands was starting to improve.However,the ecological status of the BYD wetlands on the whole is relatively less optimistic.The major factors affecting the ecological vulnerability of the BYD wetlands were found to be industrial smoke and dust emission,wetland water area,ammonia nitrogen,total phosphorus,rate of industrial solid wastes disposed,GDP per capita,etc.This illustrates that it is a systematic project to regulate wetland vulnerability and to protect regional ecological security,which may offer researchers and policy-makers specific clues for concrete interventions.

Overview of Ecological Restoration Technologies and Evaluation Systems

Ecological degradation is a global problem, and ecological restoration technologies have played and will continue to play an important role in its mitigation. However, the lack of systematic research and evaluations of ecological technologies has thus far affected their effective application in vulnerable ecological regions. This study therefore provides an overview of the main technologies for remediating soil and water erosion, desertification, and rock desertification in China and throughout the world. It addresses key issues and recommends approaches for evaluating ecological restoration technologies. Restoration technology emerged as early as 1800. Over the years such technology has changed from single objective applications to multi-purpose, multi-objective applications employing strategies that take into account ecosystem rehabilitation and integrated ecological and socioeconomic development. Along with this technological evolution, different countries have taken pertinent actions as part of their restoration initiatives. However, key issues remain, including the lack of location-specific restoration technologies and a methodological strategy to assess and prioritize existing technologies. This study proposes a four-level analytical hierarchical framework in conjunction with an indicator system that highlights the establishment and adaptation of associative indicators, while also recommending a three-phase evaluation method（The Mert）, targeting The Mert to qualitative（quick and extensive） and quantitative（detailed） evaluations in order to select the most appropriate restoration technologies available. This study can also be used as a basis for understanding the evaluation and prioritization of restoration technologies, while increasing the awareness of decision makers and the public on the role of technology in restoring degraded ecosystems.

Ecological Rehabilitation Measures in Civil Airport Construction Projects in Different Ecologically Vulnerable Regions in China

Numerous airports have been constructed based on the Twelfth Five-Year Plan for Civil Aviation Development of China. We collected relevant data on the number and distribution of civil airports, the construction of which had started or that had been assessed and approved. Based on a comparative analysis of the limits of ecological restoration in different ecologically vulnerable areas from the perspective of space, as well as an examination of ecological sensitivity factors in the ecosystems surrounding airport construction projects, suggestions concerning key ecological control techniques to be employed in airport construction projects in different ecologically vulnerable areas are put forward. The results showed that the airport construction projects recently approved by the Ministry of Water Resources and the Environmental Protection Agency are mainly distributed in the ecologically vulnerable areas of the Red Soil Hilly Area in southern China, the Karst Rocky Desertification Area in southwest China, the Agro-pastoral Ecotone in the southwestern mountain region, and the Desert-Oasis Connecting Belt in northwest China. The airport construction projects in the southwest mountain area, the hilly areas of southern China, and in the Qinghai-Tibetan Plateau are mainly based on the ecological technologies of slope protection, interception and drainage management, and vegetation restoration, respectively. In the arid and semi-arid areas, the ecological control technology employed in airport construction is mainly the rational utilization of water resources and reduction or mitigation of the effects of sandstorms. This study aims to serve as basis for soil and water conservation plans in airport construction projects and accelerate ecosystem restoration within the vicinity of airport construction sites.

The Evolution of Desertification Control and Restoration Technology in Typical Ecologically Vulnerable Regions

Global economic development and increasing human activities have brought great challenges to fragile ecosystems.In order to avoid,reduce,and reverse desertification,Chinese and foreign scientists and ecological governance institutions have developed a series of ecological restoration technologies(ERTs)and models in the past few decades.These technologies can improve residents’livelihoods,strengthen disaster resilience,and launch a comprehensive review of degraded ecosystems in desertification regions.However,some studies and practices have limited the selection and promotion of good technologies and the assessments of these technologies,resulting in the waste and loss of funds and manpower.The objective of this study is to identify desertification control and restoration technologies and models,summarize the evolutionary features and trends of these technologies under different natural conditions,and evaluate the various ERTs that are now available.The data sources of this study include the databases of international organizations,CNKI,related literature and reports,and questionnaires from institutions and experts.First,the three stages of ERTs evolution were summarized,and the key events and social-economic developments were identified as the driving forces of evolution.Then,the four categories of ERTs were identified as biological,engineering,agricultural,and management ERTs.Finally,the key ERTs were evaluated in the five dimensions of the degree of difficulty,the degree of maturity,effectiveness,suitability,and potential for transfer.The management ERTs scores for the degree of difficulty,the degree of maturity,and potential for transfer are higher.This study provides a reference for adapting to local conditions,the comprehensive management,rational development,and utilization of dryland resources,improving the application of ecological technologies,and promoting the export and import of the excellent technologies.