The impact of the endophytic bacterial community on mulberry tree growth in the Three Gorges Reservoir ecosystem, China

To improve water quality and alleviate pollution in Changshou-Fuling section of the Three Gorges Reservoir Area, an analysis methodology of regional key discharge outlet based on hydrodynamic-water quality model was developed. The EFDC model was used to study the impact of different discharge outlets on the transport of contamination in the study area by using the concept of pollutant mixing zone and pollutant mixing zone per unit load. Model calibration was conducted using observed data in 2008. Results indicated that EFDC could perfectly simulate hydrodynamics characteristics and contaminant transport process. Calculated results of pollutant mixing zone per unit load showed that the discharge outlet location in Fuling is more reasonable than that in Changshou. This study provides useful information for optimization of discharge outlets location and prediction of pollutant mixing zone in the study area, which is important for the government to make water pollution control measures.

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Effects of wet and dry seasons on the aquatic bacterial community structure of the Three Gorges Reservoir

World Journal of Microbiology and Biotechnology ◽

10.1007/s11274-012-1239-3 ◽

2013 ◽

Vol 29 (5) ◽

pp. 841-853 ◽

Cited By ~ 17

Author(s):

Zhangbao Chen ◽

Zeyang Zhou ◽

Xia Peng ◽

Heng Xiang ◽

Shaoneng Xiang ◽

...

Keyword(s):

Community Structure ◽

Bacterial Community ◽

Bacterial Community Structure ◽

Three Gorges Reservoir ◽

Three Gorges ◽

The Three Gorges Reservoir ◽

The Three Gorges ◽

Dry Seasons ◽

Wet And Dry Seasons

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Soil erosion in the Three Gorges Reservoir area

Soil Research ◽

10.1071/sr10191 ◽

2011 ◽

Vol 49 (3) ◽

pp. 212 ◽

Cited By ~ 16

Author(s):

Xibao Xu ◽

Yan Tan ◽

Guishan Yang ◽

Hengpeng Li ◽

Weizhong Su

Keyword(s):

Soil Erosion ◽

Three Gorges Reservoir ◽

Storage Period ◽

Three Gorges Reservoir Area ◽

Three Gorges ◽

Reservoir Area ◽

Modis Ndvi ◽

The Three Gorges Reservoir ◽

The Three Gorges ◽

The Impact

Spatial and temporal change in soil erosion in the Three Gorges Reservoir area since the water storage of the reservoir began filling to 135 m in 2003 is poorly understood. Using a modified soil erosion model, this study quantifies and analyses change in the extent and intensity of soil erosion in the region from 2000 to 2008. MODIS-NDVI remote sensing data (with 250 m spatial resolution) are used in the modelling and analysis of the study. The total amount, area, and intensity of soil erosion in the reservoir region presented a declining trend from 2000 to 2008. Yet there was an anomaly in the trend, in which extreme soil erosion occurred in 2003 and lasted until 2005. The average volume of soil erosion per year decreased by 4.10 × 106 t and the mean area of land experiencing soil erosion reduced by 1129.6 km2 from the pre-storage period (2000–02) to post-storage period II (2006–08). Land suffering soil erosion at high, very high, and severe levels mainly comprises forest and cropland on slopes with gradients ≥15° and is largely distributed in the eastern and south-western sections of the reservoir area. Land experiencing soil erosion at slight or moderate levels mainly involves cropland and forest on slopes with gradients ≥10° in the central section of the reservoir area. The impact of the Three Gorges Project on soil erosion since 2000 has been mainly mediated through three mechanisms: near-resettlement of rural and urban people; increased frequency and severity of geological hazards induced by rising storage of the reservoir; and implementation of ecological projects in the region. Through the former two mechanisms, soil erosion in the affected communities has been exacerbated, while the ongoing ecological projects appear to offset both the extent and intensity of soil erosion in the reservoir region. Other important factors influencing soil erosion include urban reconstruction and expansion, varying intensity of precipitation, and soil degradation.

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Land Use Pattern and Vegetation Cover Dynamics in the Three Gorges Reservoir (TGR) Intervening Basin

Water ◽

10.3390/w12072036 ◽

2020 ◽

Vol 12 (7) ◽

pp. 2036 ◽

Cited By ~ 1

Author(s):

Yi Xiong ◽

Jianzhong Zhou ◽

Lu Chen ◽

Benjun Jia ◽

Na Sun ◽

...

Keyword(s):

Land Use ◽

Vegetation Cover ◽

Three Gorges Reservoir ◽

Vegetation Coverage ◽

Driving Mechanism ◽

Three Gorges ◽

The Three Gorges Reservoir ◽

Temperature And Precipitation ◽

The Three Gorges ◽

The Impact

The Three Gorges Reservoir (TGR) intervening basin is one of the most important, ecologically fragile and sensitive areas in the upper reaches of the Yangtze River. Since the completion and operation of the TGR, the change of the ecological environment in this region—with vegetation as an indicator—has been a consistent focus of attention. Based on the six phases of land use data and normalized difference vegetation index (NDVI), temperature and precipitation data from 1998 to 2017, the change and trend of land use and vegetation cover in the TGR intervening basin were analyzed quantitatively by using a transition matrix, linear regression and partial correlation analysis. The area of unchanged land use type is 56,565 km2, accounting for 97.27% of the total area of the basin. The vegetation coverage with NDVI as the indicator showed a significant upward trend, with a growth rate of 7.5%/10a. The impact of temperature on vegetation was greater than that of precipitation on vegetation. The non-linear fitting curve of NDVI to temperature and precipitation rose with the time course of TGR impoundment, although the mechanism remains to be studied further. In general, climate change, ecological restoration measures, urbanization and reservoir impoundment did not significantly change the spatial distribution pattern of land use and the climate driving mechanism of vegetation growth in the TGR intervening basin.

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Daily and vertical dynamics of rotifers under the impact of diatom blooms in the Three Gorges Reservoir, China

Hydrobiologia ◽

10.1007/s10750-011-0793-2 ◽

2011 ◽

Vol 675 (1) ◽

pp. 29-40 ◽

Cited By ~ 5

Author(s):

Shuchan Zhou ◽

Qinghua Cai ◽

Yaoyang Xu ◽

Xinqin Han

Keyword(s):

Three Gorges Reservoir ◽

Three Gorges ◽

The Three Gorges Reservoir ◽

The Three Gorges ◽

Diatom Blooms ◽

The Impact

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Study on Characteristics of Hydrodynamic and Pollutant Transport of the Tributary Estuary in the Three Gorges Reservoir Area

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.675-677.912 ◽

2014 ◽

Vol 675-677 ◽

pp. 912-917 ◽

Cited By ~ 1

Author(s):

Zheng Wang ◽

Ying Liu ◽

Cui Hong Qin ◽

Wei Zhang

Keyword(s):

Three Gorges Reservoir ◽

Three Dimensional ◽

High Water ◽

Three Gorges Reservoir Area ◽

Three Gorges ◽

The Three Gorges Reservoir ◽

Input Action ◽

The Three Gorges ◽

Backwater Effect ◽

The Impact

To further clarify the impact of construction of the Three Gorges Reservoir on its tributaries. In this study, a three-dimensional hydrodynamic model of Changshou-Fuling section of Yangtze River was developed based on EFDC. Then an analysis of the hydrodynamics and the long term mass transport behaviors under backwater effect in the Taohuaxi River and Longxi River was presented. The results show that mainstream backwater effect plays a significant role in tributary during low-water period. And distinct circulation was shown in tributary estuary. However, in high-water period, estuarine circulation area in Longxi River decreased and disappeared, while the one in Taohuaxi River is still evident. Different input action from mainstreams to tributaries has been discovered.

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Analysis on impacts of the Three Gorges Reservoir on water temperature in the middle reach of the Yangtze River

10.5194/egusphere-egu21-3613 ◽

2021 ◽

Author(s):

Yuwei Tao ◽

Yuankun Wang ◽

Dong Wang

Keyword(s):

Water Temperature ◽

Temperature Regime ◽

Yangtze River ◽

Three Gorges Reservoir ◽

Three Gorges ◽

The Yangtze River ◽

Middle Reach ◽

The Three Gorges Reservoir ◽

The Three Gorges ◽

The Impact

<p>Water temperature, a crucial environmental factor, has a direct impact on almost all ecological and biogeochemical processes. The hydrological and thermal regimes in the Yangtze River have changed greatly due to the constructions of the Three Gorges Reservoir (TGR). To quantify the impact of TGR on the water temperature regime, we present a regression-modeling framework to reconstruct the temporal pattern of flow and temperature variation along the middle reach of the river in the absence of the TGR. By comparing reconstructed water temperatures to observed water temperature for the post-impounded period, the influence of impoundment on water temperature was estimated. Results show that TGR has had a greater impact on water temperature than natural changes in air temperature and discharge. The reservoir acts as a source of cold water in spring, summer and autumn and a warm source in winter. The results of this study illustrate the pronounced effect of the TGR on the temperature regime of the Yangtze River. We hope this study could provide a scientific reference for ecological operation of TGR facing biological conservation.</p><p>Note: This study has been published in Journal of Hydrology (Tao, Y., Wang, Y., Rhoads, B., Wang, D., Ni, L. and Wu, J., 2020. Quantifying the impacts of the Three Gorges Reservoir on water temperature in the middle reach of the Yangtze River. Journal of Hydrology. 582.).</p>

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Assessment of the Suitability of Wintering Anatidae Habitats before and after Impoundment in the Three Gorges Reservoir Region

Sustainability ◽

10.3390/su13094743 ◽

2021 ◽

Vol 13 (9) ◽

pp. 4743

Author(s):

Xiuming Li ◽

Ruimei Cheng ◽

Wenfa Xiao ◽

Ge Sun ◽

Tian Ma ◽

...

Keyword(s):

Yangtze River ◽

Three Gorges Reservoir ◽

Main Stream ◽

Three Gorges ◽

The Yangtze River ◽

The Three Gorges Reservoir ◽

The Three Gorges ◽

Three Gorges Reservoir Region ◽

Surrounding Areas ◽

The Impact

In this study, we aimed to understand the distribution of and changes in the habitats suitable for Anatidae wintering in the Three Gorges Reservoir Region (TGRR), China, and to explore the impact of the impoundment during different impoundment periods. Based on species occurrence data for four dominant species of Anatidae and environmental factors, a maximum entropy (MaxEnt) model was used to analyze the suitability of habitats during five impoundment periods. The results show that the main factors affecting Anatidae distribution were temperature and roads before the Three Gorges Project (TGP) and elevation after the TGP. After the TGP, the area of the suitable habitat declined rapidly and then gradually increased with increasing water level. After impoundment, the primary area of increased habitat suitability was the main stream of the Yangtze River from Changshou District to Yunyang County and its tributary in the Kaizhou area. Among the habitats, the central water regions were more suitable than the marginal shoal areas. Anatidae habitats in the TGRR were distributed mainly within the Yangtze River main stream and the surrounding areas before the TGP, and the surrounding areas largely disappeared after the TGP, particularly in Chongqing City and Jiangjin District. In this context, it is challenging to create new protected areas within the habitat suitable for Anatidae in the main stream of the Yangtze River; we propose adding the Anatidae as conservation targets within the existing conservation agencies and implementing a waterbird monitoring program for scientific waterbird conservation and the sustainable development of the reservoir.

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