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Projecting Spring Consecutive Rainfall Events in the Three Gorges Reservoir Based on Triple-Nested Dynamical Downscaling 被引量:2
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作者 Yanxin ZHENG Shuanglin LI +2 位作者 Noel KEENLYSIDE Shengping HE Lingling SUO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1539-1558,共20页
Spring consecutive rainfall events(CREs) are key triggers of geological hazards in the Three Gorges Reservoir area(TGR), China. However, previous projections of CREs based on the direct outputs of global climate model... Spring consecutive rainfall events(CREs) are key triggers of geological hazards in the Three Gorges Reservoir area(TGR), China. However, previous projections of CREs based on the direct outputs of global climate models(GCMs) are subject to considerable uncertainties, largely caused by their coarse resolution. This study applies a triple-nested WRF(Weather Research and Forecasting) model dynamical downscaling, driven by a GCM, MIROC6(Model for Interdisciplinary Research on Climate, version 6), to improve the historical simulation and reduce the uncertainties in the future projection of CREs in the TGR. Results indicate that WRF has better performances in reproducing the observed rainfall in terms of the daily probability distribution, monthly evolution and duration of rainfall events, demonstrating the ability of WRF in simulating CREs. Thus, the triple-nested WRF is applied to project the future changes of CREs under the middle-of-the-road and fossil-fueled development scenarios. It is indicated that light and moderate rainfall and the duration of continuous rainfall spells will decrease in the TGR, leading to a decrease in the frequency of CREs. Meanwhile, the duration, rainfall amount, and intensity of CREs is projected to regional increase in the central-west TGR. These results are inconsistent with the raw projection of MIROC6. Observational diagnosis implies that CREs are mainly contributed by the vertical moisture advection. Such a synoptic contribution is captured well by WRF, which is not the case in MIROC6,indicating larger uncertainties in the CREs projected by MIROC6. 展开更多
关键词 triple-nested downscaling Three gorges reservoir area consecutive rainfall events geological hazards PROJECTION
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Microplastics in sediment of the Three Gorges Reservoir:abundance and characteristics under different environmental conditions
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作者 Wang LI Bo ZU +2 位作者 Yiwei LIU Juncheng GUO Jiawen LI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期101-112,共12页
Freshwater microplastic pollution is an urgent issue of global concern,and research on the distribution in reservoirs is lacking.We investigated the microplastic pollution levels in wet sediments collected from the Th... Freshwater microplastic pollution is an urgent issue of global concern,and research on the distribution in reservoirs is lacking.We investigated the microplastic pollution levels in wet sediments collected from the Three Gorges Reservoir,the largest reservoir of China.Results show that microplastics were ubiquitous in the sediments of the Three Gorges Reservoir,and their abundance ranged from 59 to 276 pp/kg(plastic particles per kg,dry weight).Economic development and total population were important factors affecting the spatial heterogeneity of microplastic abundance,and the contribution of large cities along the reservoir to microplastic pollution should be paid with more attention.Fibrous microplastics were the most abundant type of microplastic particles in reservoir sediments,whereas polystyrene,polypropylene,and polyamide were the main types of polymers.The apparent spatial heterogeneity in morphology and color of microplastics is attributed to different anthropogenic or landbased pollution sources.Moreover,the accumulation of microplastics near the inlet of tributaries reflects the role of potential contributors of tributaries.More importantly,multiple bisphenols(BPs)and heavy metals detected at the microplastic surfaces indicate that microplastics can act as carriers of these pollutants in the environment in the same way as sediments did,which may alter the environmental fate and toxicity of these pollutants.Therefore,we conclude that the Three Gorges Reservoir had been contaminated with microplastics,which posed a stress risk for organisms who ingest them along with their associated pollutants(BPs,heavy metals). 展开更多
关键词 microplastics Three gorges reservoir SEDIMENT BISPHENOL heavy metal
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Characteristics and influencing mechanisms of production-living-ecological space dynamics in the Three Gorges Reservoir Area(TGRA),Chongqing,China
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作者 ZHU Xinyi GAO Jinlong 《Regional Sustainability》 2024年第2期49-62,共14页
The Three Gorges Reservoir Area(TGRA)is an important ecological barrier in the Yangtze River Basin,China.Therefore,it is of great importance to understand the spatio-temporal variation and the driving factors of produ... The Three Gorges Reservoir Area(TGRA)is an important ecological barrier in the Yangtze River Basin,China.Therefore,it is of great importance to understand the spatio-temporal variation and the driving factors of production-living-ecological spaces for sustainable and high-quality development in the TGRA.This study investigated the dynamic variation of production-living-ecological spaces in the TGRA by employing land use data in 2000,2005,2010,2015,and 2018,and detected the influencing factors by using the Geographic detector(GeoDetector).Results implied that the structure and dynamic trajectories of production-living-ecological spaces in the TGRA varied in both horizontal and vertical directions,and the study area was dominated by ecological space.A spatial orientation towards the northeast was detected in the evolution of production-living-ecological spaces during 2000-2018.In terms of quantity,the transition from ecological space(grassland and woodland)to agriculture land accounted for the largest proportion from 2000 to 2018.However,the reverse transition from agriculture land to ecological space has increased since 2000 with the efforts of“Grain for Green”.In terms of temporal scale,there was a fluctuating trend in production space with the continuous expansion of living space,while ecological space showed an inverted U-shaped trend during 2000-2018.The dynamic pattern of production-living-ecological spaces in the TGRA was influenced by both physical and socio-economic variables as basic determinants and dominant driving factors,respectively.Finally,the harmonization and protection of production-living-ecological spaces still require policy-makers’efforts.This work may have potential in advancing our understanding about land use conflicts,and provide a reference for rational layout of spatial functions and the realization of sustainable development in the TGRA. 展开更多
关键词 Production-living-ecological spaces Functional transition Three gorges reservoir Area(TGRA) Physical and socio-economic variables Yangtze River
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Environmental heterogeneity and productivity drive the assemblage of benthic diatom:a case study of the Three Gorges Reservoir
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作者 Songqi YANG Tian OUYANG +4 位作者 Shaojun XU Lu ZHAO Lulu JI Junqiong SHI Zhongxing WU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第3期991-1006,共16页
Dam construction has a critical effect on river ecosystems in the world,resulting in a rapid decline in biodiversity and ecosystem health.However,the effect of dam construction on the assemblage pattern of benthic dia... Dam construction has a critical effect on river ecosystems in the world,resulting in a rapid decline in biodiversity and ecosystem health.However,the effect of dam construction on the assemblage pattern of benthic diatoms remains unclear.The benthic diatoms assemblages in the tributary backwater area of the Three Gorges Reservoir(TGR)were investigated under low water level(LWL)and high water level(HWL)conditions.Results show that Discostella stelligera,Nitzschia palea,and Craticula subminuscula were dominant species in LWL,while Achnanthidium minutissimum and Nitzschia dissipata were dominant in HWL.Furthermore,environmental variables,productivity parameters,diversity indices,and community similarity were found significantly different between LWL and HWL periods.The Mantel test indicated that both environmental and spatial factors had significant effects on diatom communities in backwater area,while productivity was also a key driving force in LWL.The variation partitioning analysis(VPA)further demonstrated that environment factors could explain the largest variance of diatom assemblages in HWL(9%)and LWL(11%),followed by spatial factors.The relative importance of productivity to diatom community was significantly enhanced in LWL,but only a slight effect was found in HWL.These results indicate that the diatom assemblages were shaped by both environmental filtering and spatial factors.The relative importance of spatial factors depended on the degree of productivity.Therefore,the homogenization of diatom communities due to environmental disturbance,e.g.eutrophication and dam building,is the underlying mechanism in assembling the benthic diatoms. 展开更多
关键词 Three gorges reservoir benthic diatom ASSEMBLAGE environmental heterogeneity PRODUCTIVITY
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Climate Characteristics in Three Gorges Reservoir Area after Water Storage and Its Impact on the Production Potential
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作者 钟海玲 高荣 杨霞 《Meteorological and Environmental Research》 CAS 2010年第2期53-56,共4页
Based on the meteorological data from 33 stations of Three Gorges Reservoir from 1960 to 2008,climate yield of rice,corn and winter wheat and the changes of climatic potential productivity after water storage in Three... Based on the meteorological data from 33 stations of Three Gorges Reservoir from 1960 to 2008,climate yield of rice,corn and winter wheat and the changes of climatic potential productivity after water storage in Three Gorges Reservoir were calculated by the dynamic statistic model of crop growth.The results showed that the temperature in Three Gorges Reservoir was fluctuant decreased before late 1980s,and warmed rapidly after the late 1980s.The precipitation had little change before the late 1990s and had a slight decrease after the late 1990s.Sunshine hours were more in 1960s and 1970s,and then it changed little after 1980s.After water storage,the temperature increased in Three Gorges Reservoir as a whole.The precipitation decreased in the south of Three Gorges Reservoir,while it increased in the northwest of Three Gorges Reservoir.The sunshine hours were reduced except that in the vicinity of Dianjiang.After water storage,climatic potential productivity of rice decreased in the northwest and the northeast,while it increased in the south of Three Gorges Reservoir.The climatic potential productivity of corn decreased in the northeast and the southwest,but increased in the rest of Three Gorges Reservoir.The climatic potential productivity of winter wheat increased almost in total. 展开更多
关键词 Three gorges reservoir area Water storage Climatic potential productivity CHANGE China
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Strategies for Safe Land Use of the Three Gorges Reservoir Area (Chongqing Section)——With the Restoration of Degraded Forest Landscapes as a Study Case
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作者 牟萍 《Journal of Landscape Research》 2010年第8期51-55,共5页
As a key for constructing ecologically safe scenery, forest landscape pattern in Chongqing Section of the Three Gorges has shown degradation, fragmentation and revision of varying degrees. To ensure normal and safe op... As a key for constructing ecologically safe scenery, forest landscape pattern in Chongqing Section of the Three Gorges has shown degradation, fragmentation and revision of varying degrees. To ensure normal and safe operation of the Three Gorges, and meet requirements of integrated development strategies for ecological and economic effects in Chongqing City on the ecological security of land use in Chongqing section of the Three Gorges, the following points should be attached more importance in making future strategies for an ecologically safe land use pattern with the restoration of degraded forest landscape as its starting point:a. Ecological effects and economic functions that can be supplied by forest landscape elements in different restoration patterns should be understood to obtain background effect of the ecological security pattern scenario of land use in the reservoir region; b. Relationship between restoration of degraded forest landscapes and serious ecological interference factors such as degradation background, artificial disturbance and engineering stress, should be simulated to figure out the influence of natural or artificial driving factors on landscape pattern, determine the future restoration mode for the degraded forest landscapes in the reservoir region, so as to facilitate the construction of great ecological-economic security pattern of the Three Gorges. The findings will provide scientific basis for the decision-making in building an ecologically safe land use pattern in the Three Gorges reservoir area (Chongqing), when using the degradation of forest landscape restoration as a carrier at present or in the future. Further, they will help realize the development goals of "Livable Chongqing, Expedite Chongqing, Forestry Chongqing, Safe Chongqing and Healthy Chongqing". 展开更多
关键词 LAND use Ecological-economic security Forest LANDSCAPE The Three gorges reservoir region
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Preliminary Study on Early-warning System of Ecological Security in Water-Level-Fluctuating Zone (WLFZ) of Three Gorges Reservoir 被引量:2
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作者 郑磊 左太安 李月臣 《Agricultural Science & Technology》 CAS 2010年第5期159-164,共6页
The area,the scope as well as some ecological environment questions in Three Gorges Reservoir was briefly introduced. Then its early warning-system frame was preliminarily constructed,which includes ecological securit... The area,the scope as well as some ecological environment questions in Three Gorges Reservoir was briefly introduced. Then its early warning-system frame was preliminarily constructed,which includes ecological security dynamic monitoring,ecological security appraisal,ecological security forecast and ecological security decision-making management. The synthetic evaluation indicator system of the ecological security quality were initially established,which includes ecological environment pollution,land use and land cover change,geological hazard and epidemic outbreaks. At the same time,29 evaluating indicators were selected,divides into the basic factors,response factors and inducing factors,which need to be Real-time monitored. 展开更多
关键词 Ecological security Early warning system Fuzzy mathematics Three gorges reservoir Water-Level-Fluctuating Zone (WLFZ)
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Plankton community composition in the Three Gorges Reservoir Region revealed by PCR-DGGE and its relationships with environmental factors 被引量:27
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作者 YAN Qingyun YU Yuhe +2 位作者 FENG Weisong YU Zhigang CHEN Hongtao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第6期732-738,共7页
To explore the relationships between community composition and the environment in a reservoir ecosystem, plankton communities from the Three Gorges Reservoir Region were studied by PCR-denaturing gradient gel electrop... To explore the relationships between community composition and the environment in a reservoir ecosystem, plankton communities from the Three Gorges Reservoir Region were studied by PCR-denaturing gradient gel electrophoresis fingerprinting. Bacterial and eukaryotic operational taxonomic units (OTUs), generated by DGGE analysis of the PCR-amplified 16S and 18S rRNA genes, were used as surrogates for the dominant "biodiversity units". OTU composition among the sites was heterogeneous; 46.7% of the total bacterial OTUs (45) and 64.1% of the eukaryotic OTUs (39) were identified in less than half of the sampling sites. Unweighted pair group method with arithmetic averages (UPGMA) clustering of the OTUs suggested that the plankton communities in the Xiangxi Rive sites were not always significantly different from those from the Yangtze River sites, despite clear differences in their environmental characterizations. Canonical correspondence analysis (CCA) was applied to further investigate the relationships between OTU composition and the environmental factors. The first two CCA ordination axes suggested that the bacterial community composition was primarily correlated with the variables of NO3^--N, dissolved oxygen (DO), and SiO3^2--Si, whereas, the eukaryotic community was mainly correlated with the concentrations of DO, PO4^3--P, and SiO3^2--Si. 展开更多
关键词 plankton community environmental factors denaturing gradient gel electrophoresis (DGGE) spatial pattern Three gorges reservoir Region
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Reductions in non-point source pollution through different management practices for an agricultural watershed in the Three Gorges Reservoir Area 被引量:13
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作者 Yaowu Tian Zhilin Huang Wenfa Xiao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第2期184-191,共8页
Non-point source water pollution generated by agricultural production is considered a major environmental issue in the Three Gorges Reservoir Area (TGRA) of China. The Annualised Agricultural Non-Point Source Pollut... Non-point source water pollution generated by agricultural production is considered a major environmental issue in the Three Gorges Reservoir Area (TGRA) of China. The Annualised Agricultural Non-Point Source Pollution (AnnAGNPS) model was selected to assess the impact of the application of various management treats, including seven crops, five fertilizer levels and three-group management practice scenarios, on water quality from Heigou River Watershed in TGRA. The scenario subsets include conservation tillage practice (CTP), conservation reserve program (CRP) and conversion of cropland into forestland program (CCFP). Results indicated that tea can not be replaced by other crops because comparatively tea resulted in a higher sediment yield. CTP with no-tillage was more effective to reduce sediment yield, but could increased nutrient loss. CRP reduced sediment yield significantly, but slightly benefited on nutrient loss. CCFP reduced not only sediment yield but also the nutrient loss significantly. The conversion of cropland with a slope greater than 10° into forestland was found to be the best scenario as the sediment yield export is less than 5 tons/ha and nutrient loss is within the permissible limit. 展开更多
关键词 non-point pollution management practice REDUCTION the Three gorges reservoir Area
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Effect of nitrogen and phosphorus on the water quality in the Three Gorges Reservoir Area during and after its construction 被引量:10
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作者 LIUHong LIUHui-juan QUJiu-hui 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第3期358-363,共6页
A survey concerning the concentration of the nutrients in the Three Gorges Reservoir Area was carried out. This paper presents the parameters(NO 3 - N, NO 2 - N, Kjeldahl N, non ionic ammonia, P PO 4 and TP)... A survey concerning the concentration of the nutrients in the Three Gorges Reservoir Area was carried out. This paper presents the parameters(NO 3 - N, NO 2 - N, Kjeldahl N, non ionic ammonia, P PO 4 and TP) determined at 16 sampling sites from 1997 to 1999 The dominant soluble nitrogen form was NO 3 - N followed by Kjeldahl N, NO 2 - N and non ionic ammonia. Mean values of NO 3 - N, NO 2 - N, Kjeldahl N and non ionic ammonia ranged from 0 50 to 2 37 mg/L, 0 022 to 0 084 mg/L, 0 33 to 0 99 mg/L and 0 007 to 0 092 mg/L respectively. Mean values of P PO 4 at most sampling sites were higher than 0 1 mg/L for subject to eutrophication. The major factors influencing the concentrations of N and P might be agricultural runoff, municipal and industrial effluents. In addition, 6 kinds of soil were sampled at the area where would inundated after the dam completed. Two approaches were adopted to simulate the N and P release from the inundated soils. The results showed that the soils would release nitrogen and phosphorus to the overlying water when the soils were inundated. The characteristics of soil affected the equilibrium concentrations of N and P between the soil and the overlying water. 展开更多
关键词 Three gorges reservoir Area NITROGEN PHOSPHORUS inundated soil
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Mapping landslide susceptibility at the Three Gorges Reservoir, China, using gradient boosting decision tree,random forest and information value models 被引量:9
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作者 CHEN Tao ZHU Li +3 位作者 NIU Rui-qing TRINDER C John PENG Ling LEI Tao 《Journal of Mountain Science》 SCIE CSCD 2020年第3期670-685,共16页
This work was to generate landslide susceptibility maps for the Three Gorges Reservoir(TGR) area, China by using different machine learning models. Three advanced machine learning methods, namely, gradient boosting de... This work was to generate landslide susceptibility maps for the Three Gorges Reservoir(TGR) area, China by using different machine learning models. Three advanced machine learning methods, namely, gradient boosting decision tree(GBDT), random forest(RF) and information value(InV) models, were used, and the performances were assessed and compared. In total, 202 landslides were mapped by using a series of field surveys, aerial photographs, and reviews of historical and bibliographical data. Nine causative factors were then considered in landslide susceptibility map generation by using the GBDT, RF and InV models. All of the maps of the causative factors were resampled to a resolution of 28.5 m. Of the 486289 pixels in the area,28526 pixels were landslide pixels, and 457763 pixels were non-landslide pixels. Finally, landslide susceptibility maps were generated by using the three machine learning models, and their performances were assessed through receiver operating characteristic(ROC) curves, the sensitivity, specificity,overall accuracy(OA), and kappa coefficient(KAPPA). The results showed that the GBDT, RF and In V models in overall produced reasonable accurate landslide susceptibility maps. Among these three methods, the GBDT method outperforms the other two machine learning methods, which can provide strong technical support for producing landslide susceptibility maps in TGR. 展开更多
关键词 MAPPING LANDSLIDE SUSCEPTIBILITY Gradient BOOSTING decision tree Random FOREST Information value model Three gorges reservoir
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Fractal characterization of sediment particle-size distribution in the water-level fluctuation zone of the Three Gorges Reservoir, China 被引量:7
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作者 LI Jin-lin BAO Yu-hai +3 位作者 WEI Jie HE Xiu-bin TANG Qiang Jean de Dieu NAMBAJIMANA 《Journal of Mountain Science》 SCIE CSCD 2019年第9期2028-2038,共11页
The combined effect of periodic water impoundment and seasonal natural flood events has created a 30 m high water-level fluctuation zone(WLFZ) around the Three Gorges Reservoir(TGR), China, forming a unique eco-landsc... The combined effect of periodic water impoundment and seasonal natural flood events has created a 30 m high water-level fluctuation zone(WLFZ) around the Three Gorges Reservoir(TGR), China, forming a unique eco-landscape. Siltation, eutrophication, enrichment of heavy metals, and methane emissions in the WLFZ have been widely associated with sediment and soil particles generated from the upstream catchment or upland slopes. However, little attention has been paid to the complexity of sediment particle-size distributions in the WLFZ. In the present study, core samples(from a 345 cm thick sediment core from the base of the WLFZ), slope transect surface samples(across/up a WLFZ slope), and along-river/longitudinal surface samples(from the reservoir reaches) were collected. Laser granulometry and a volume-based fractal model were used to reveal the characteristics of sediment particle-size distributions. Results indicate that the alternation of coarse and fine particles in the sedimentary core profile is represented as a fluctuation of low and high values of fractal dimension(D), ranging from 2.59 to 2.77. On the WLFZ slope transect, surface sediment particles coarsen with increasing elevation, sand content increases from 3.3% to 78.5%, and D decreases from 2.76 to 2.53. Longitudinally, surface sediments demonstrate a downstream-fining trend, and D increases gradually downstream. D is significantly positively correlated with the fine particle content. We conclude that D is a useful measure for evaluating sediment particle-size distribution. 展开更多
关键词 Spatial DIFFERENTIATION SEDIMENT particle FRACTAL dimension WATER-LEVEL FLUCTUATION ZONE Three gorges reservoir
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Displacement characteristics and prediction of Baishuihe landslide in the Three Gorges Reservoir 被引量:5
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作者 LI De-ying SUN Yi-qing +3 位作者 YIN Kun-long MIAO Fa-sheng Thomas GLADE Chin LEO 《Journal of Mountain Science》 SCIE CSCD 2019年第9期2203-2214,共12页
In order to reach the designated final water level of 175 m, there were three impoundment stages in the Three Gorges Reservoir, with water levels of 135 m, 156 m and 175 m. Baishuihe landslide in the Reservoir was cho... In order to reach the designated final water level of 175 m, there were three impoundment stages in the Three Gorges Reservoir, with water levels of 135 m, 156 m and 175 m. Baishuihe landslide in the Reservoir was chosen to analyze its displacement characteristics and displacement variability at the different stages. Based on monitoring data, the landslide displacement was mainly influenced by rainfall and drawdown of the reservoir water level. However, the magnitude of the rise and drawdown of the water level after the reservoir water level reached 175 m did not accelerate landslide displacement. The prediction of landslide displacement for active landslides is very important for landslide risk management. The time series of cumulative displacement was divided into a trend term and a periodic term using the Hodrick-Prescott(HP) filter method. The polynomial model was used to predict the trend term. The extreme learning machine(ELM) and least squares support vector machine(LS-SVM) were chosen to predict theperiodic term. In the prediction model for the periodic term, input variables based on the effects of rainfall and reservoir water level in landslide displacement were selected using grey relational analysis. Based on the results, the prediction precision of ELM is better than that of LS-SVM for predicting landslide displacement. The method for predicting landslide displacement could be applied by relevant authorities in making landslide emergency plans in the future. 展开更多
关键词 LANDSLIDE THREE gorges reservoir IMPOUNDMENT process DISPLACEMENT PREDICTION
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Changes in cultivated land patterns and driving forces in the Three Gorges Reservoir area, China, from 1992 to 2015 被引量:9
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作者 ZHANG Yu-xin WANG Yu-kuan +5 位作者 FU Bin LI Ming LU Ya-feng DIXIT Amod Mani CHAUDHARY Suresh WANG Shan 《Journal of Mountain Science》 SCIE CSCD 2020年第1期203-215,共13页
Changes of cultivated land patterns caused by major water conservation projects are rarely reported. We selected the Three Gorges Reservoir area in China to study the change in area and landscape pattern of the cultiv... Changes of cultivated land patterns caused by major water conservation projects are rarely reported. We selected the Three Gorges Reservoir area in China to study the change in area and landscape pattern of the cultivated land in the head,central, and tail areas of the reservoir that took place between 1992 and 2015;we then studied the spatial distribution of the cultivated land in the three parts of the reservoir;finally, we studied the driving forces behind the changes in the cultivated land. The results derived are as follows.(1) During the construction of the Three Gorges Project(TGP, 1992–2015), the area of cultivated land around the reservoir decreased by30.23 million ha. This reduction occurred in phases:the most severe change in cultivated land occurred during the later stage of the project(2002–2010);only 0.62 million ha of cultivated land did not change between 1992 and 2015.(2) Spatial pattern analysis showed that the cultivated land in the three parts of the reservoir changed from a northern distribution to a southern distribution;thus, the area of cultivated land in the north decreased over the time period. The area of cultivated land in the head and tail areas decreased by varying degrees, while it increased in the central area over the 23 years, indicating that the change in cultivated land showed regional differences.(3) The TGP, the policy of reverting farmland to forest,and urbanization were the main driving factors for the change of cultivated land, but there were differences in their impacts at different stages.(4) According to the patch dynamics of the land cover change, the degree of change gradually intensified during the early and later stages of the project and then stabilized during the operational period. Our research provides scientific support for the protection of cultivated land resources and food security in the reservoir area and for the coordination of social and economic development, which is of great significance to sustainable development in the reservoir area. 展开更多
关键词 Agricultural land change Three gorges reservoir area Landscape index The standard deviation ellipse Cultivated land Driving forces
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Landslides and Slope Aspect in the Three Gorges Reservoir Area Based on GIS and Information Value Model 被引量:6
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作者 WU Caiyan QIAO Jianping WANG Meng 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期773-779,共7页
Slope aspect is one of the indispensable internal factors besides lithology, relative elevation and slope degree. In this paper authors use information value model with Geo graphical Information System (GIS) technol... Slope aspect is one of the indispensable internal factors besides lithology, relative elevation and slope degree. In this paper authors use information value model with Geo graphical Information System (GIS) technology to study how slope aspect contributes to landslide growth from Yunyang to Wushan segment in the Three Gorges Reservoir area, and the relationship between aspect and landslide growth is quantified. Through the research on 205 landslides examples, it is found that the slope contributes most whose aspect is towards south,southeast and southwest aspect contribute moderately, and other five aspects contribute little. The research result inosculates preferably with the fact. The result of this paper can provide potent gist to the construction of Three Gorges Reservoir area in future. 展开更多
关键词 the Three gorges reservoir region LANDSLIDE ASPECT GIS information value model
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Prediction of chlorophyll a concentration using HJ-1 satellite imagery for Xiangxi Bay in Three Gorges Reservoir 被引量:7
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作者 Dong-xing FAN Yu-ling HUANG +3 位作者 Lin-xu SONG De-fu LIU Ge ZHANG Biao ZHANG 《Water Science and Engineering》 EI CAS CSCD 2014年第1期70-80,共11页
Since the impoundment of the Three Gorges Reservoir in 2003, algal blooms have frequently been observed in it. The chlorophyll a concentration is an important parameter for evaluating algal blooms. In this study, the ... Since the impoundment of the Three Gorges Reservoir in 2003, algal blooms have frequently been observed in it. The chlorophyll a concentration is an important parameter for evaluating algal blooms. In this study, the chlorophyll a concentration in Xiangxi Bay, in the Three Gorges Reservoir, was predicted using HJ-1 satellite imagery. Several models were established based on a correlation analysis between in situ measurements of the chlorophyll a concentration and the values obtained from satellite images of the study area from January 2010 to December 2011. Chlorophyll a concentrations in Xiangxi Bay were predicted based on the established models. The results show that the maximum correlation is between the reflectance of the band combination of B4/(B2+B3) and in situ measurements of chlorophyll a concentration. The root mean square errors of the predicted values using the linear and quadratic models are 18.49 mg/m3 and 18.52 mg/m3, respectively, and the average relative errors are 37.79% and 36.79%, respectively. The results provide a reference for water bloom prediction in typical tributaries of the Three Gorges Reservoir and contribute to large-scale remote sensing monitoring and water quality management. 展开更多
关键词 chlorophyll a concentration H J-1 satellite remote sensing prediction correlation analysis Xiangxi Bay Three gorges reservoir
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Dynamics of Rodent and Rodent-borne Disease during Construction of the Three Gorges Reservoir from 1997 to 2012 被引量:5
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作者 CHANG Zhao Rui LU Liang +7 位作者 MAO De Qiang PAN Hui Ming FENG Lian Gui YANG Xiao Bing LIU Feng Feng HE Yuan Yuan ZHANG Jing YANG Wei Zhong 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2016年第3期197-204,共8页
Objective To investigate the impact of impoundment and active public health interventions on rodent populations and rodent-borne diseases in the Three Gorges reservoir region from 1997 to 2012. Methods Surveillance da... Objective To investigate the impact of impoundment and active public health interventions on rodent populations and rodent-borne diseases in the Three Gorges reservoir region from 1997 to 2012. Methods Surveillance data from 1997 to 2012 were extracted from the Public Health Surveillance System of The Three Gorges established in 1997. Temporal changes in the incidences of hemorrhagic fever with renal syndrome (HFRS) and leptospirosis, rodent density, pathogen-carrying rates, and their correlations were analyzed. Results The average indoor and outdoor rodent densities decreased overall from 1997 to 2012. The average densities decreased by 47.72% (from 4.38% to 2.29%) and 39.68% (from 4.41% to 2.66%), respectively, after impoundment (2003-2012) compared with before impoundment (1997-2002). The average annual incidence rates of HFRS and leptospirosis were 0.29/100,000 and 0.52/100,000, respectively, and decreased by 85.74% (from 0.68/100,000 to 0.10/100,000) and 95.73% (from 1.47/100,000 to 0.06S/100,000), respectively, after impoundment compared with before impoundment. Incidences of HFRS and leptospirosis appear to be positively correlated with rodent density in the reservoir area. Conclusion This study demonstrated that rodent density and incidences of rodent-borne diseases decreased and were maintained at low levels during construction of the Three Gorges dam. Measures that reduce rodent population densities could be effective in controlling rodent-borne diseases during large-scale hydraulic engineering construction. 展开更多
关键词 Three gorges reservoir Rodent density Rodent-borne diseases
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Surface Microtextures of Slipping Zone Soil of Some Landslides in the Three Gorges Reservoir District and Their Significance 被引量:5
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作者 YAN Chunjie SUN Yunzhi TANG Huiming 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第2期349-352,共4页
The mineral assemblage and content and surface microtextures of slipping zone soil of several landslides in the Three Gorges Reservoir District have been analyzed using the scanning electron microscope (SEM) and X-ray... The mineral assemblage and content and surface microtextures of slipping zone soil of several landslides in the Three Gorges Reservoir District have been analyzed using the scanning electron microscope (SEM) and X-ray diffractometer (XRD). All the mineral assemblages are similar in these landslides. The main minerals are montmorillonite, illite, kaolinite, chlorite, quartz and feldspar. There are two kinds of surface microtexture in the slipping zone soil, i.e., linear scratches and arcuate scratches. Based on analyses of the changes of the microtextures, one can obtain information about the number, directions and stages of landslide movements. The authors have also studied the mechanism of landslide formation, evaluated the stability of landslides and revival possibility of ancient landslides and forecasted the activity of similar landslides in different districts. The surface microtexture features of stable landslides and mobile landslides are summarized and it is concluded that the existence of filamentous bacteria may result in or increase movements of landslides. 展开更多
关键词 The Three gorges reservoir district LANDSLIDE surface microtexture scanning electron microscope (SEM)
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Land Use of the Three Gorges Reservoir Area and the Effect on Its Landscape Pattern in the Recent 50 Years 被引量:7
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作者 HUANG Zhiqin 1,2,3 , ZHOU Wancun 1 ,ZHOU Jieming 4 , ZHU Mingcang 3,5 1. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences , Chengdu 610041, Sichuan, China 2. Graduate University of Chinese Academy of Sciences, Beijing 100049, China +2 位作者 3. Sichuan Institute of Land Resource Management, Chengdu 610041, Sichuan , China 4. Department of Resources and Environment Science, Sichuan Normal University , Chengdu 610061, Sichuan, China 5. College of Information Engineering, Chengdu University of Technology, Chengdu 610059, Sichuan, China 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期910-914,共5页
The paper makes detailed analysis on the changing processes of the main types of land use in Three Gorges Reservoir Area through the techniques of RS (Remote Sense) and GIS (Geography Information System). Based on... The paper makes detailed analysis on the changing processes of the main types of land use in Three Gorges Reservoir Area through the techniques of RS (Remote Sense) and GIS (Geography Information System). Based on the theory of landscape ecology, many types of landscape pattern indexes are calculated and made correlation analysis. The results indicate that: in 1995 the ecological environment of Three Gorges Reservoir Area was the most vulnerable in the recent 50 years, but resumed in 2002; the landscape pattern diversity index, fractal dimension index and fragmentation index has close correlation with the area of land use/cover change (LUCC). The research also releases that the increase of the cultivated land, grassland and construction land deteriorates the landscape ecological pattern, while the increase of forest land area will help restore the landscape ecological pattern to its original state. The rapid change of grassland is an important index of the change of landscape pattern, because it has the most effect on change of landscape pattern index. 展开更多
关键词 the Three gorges reservoir Area land use/cover change landscape pattern.
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Conflict between wild boars(Sus scrofa) and farmers:distribution, impacts,and suggestions for management of wild boars in the Three Gorges Reservoir Area 被引量:3
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作者 LIU Qin YAN Kun +2 位作者 LU Ya-feng LI Ming YAN Yang-yang 《Journal of Mountain Science》 SCIE CSCD 2019年第10期2404-2416,共13页
Economic losses caused by wild boars(Sus scrofa)continue to increase in the Three Gorges Reservoir Area.We selected 206 farmers in Wuqiaohe Basin as survey respondents using random stratified sampling.The distribution... Economic losses caused by wild boars(Sus scrofa)continue to increase in the Three Gorges Reservoir Area.We selected 206 farmers in Wuqiaohe Basin as survey respondents using random stratified sampling.The distribution and impacts of wild boars were examined using a questionnaire survey and spatial analysis.The results showed that:(1)The density of farmer settlements is low and most peasants’households are located on the forest edge.Due to large-scale labor migration,a high proportion of farmland(25.85%)has been abandoned and an even higher proportion of farmland(40.48%)has been returned to forest.(2)The probability of wild boar damage to peasant households was 67.96%.Yields of corn and sweet potato decreased by 24.87%and 28.24%,respectively,with a total economic loss of approximately 2,590,100 RMB/yr in the Wuqiaohe basin.Sixty-five percent of the affected cultivatedlands were located within approximately 150 m of the forest edges.(3)The wild boar damage coefficient was significantly and negatively correlated with the distance between the peasants’household and the forest edge,the density of the settlements,and the area of cultivated land.The wild boar damage coefficient shows a significant positive correlation with the area of farmland returned to forest.(4)The damage activity caused by wild boars began to occur7-8 years ago,and the destruction has been more frequently and seriously observed in the last 4-5 years.(5)We make suggestions for wild boar control and management measures including developing a compensation policy.The compensation standard is related to the land area returning from farmland to forests and the actual cultivated land area. 展开更多
关键词 DISTRIBUTION features Economic loss MANAGEMENT Three gorges reservoir Area Wild BOAR
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