[Quantitative Analysis of the Correlation Between Macrobenthos Community and Water Environmental Factors and Aquatic Ecosystem Health Assessment in the North Canal River Basin of Beijing].

Macrobenthos can reflect the cumulative effect of various ecological threats on the water environment and are closely related to the health of river ecosystems. In this study, taking the North Canal River basin, a typical basin in Beijing, as an example, ecological data from 34 stations were investigated in the summer of 2015. Characteristics of the macrobenthos communities were analyzed, and driving environmental factors were identified using typical correspondence analysis.

[Impact of Spatial Heterogeneity of Precipitation on the Area Change in Critical Source Area of Non-point Sources Pollution].

Aiming at non-point sources pollution in the agricultural areas with large topographic fluctuations and spatial differences in precipitation, a SWAT model was used to evaluate the spatial variations in the critical source areas (CSAs) of total nitrogen (TN) and total phosphorus (TP) under two precipitation scenarios, i.e., heterogeneous precipitation and uniform precipitation.

[Health Assessment of the Stream Ecosystem in the North Canal River Basin, Beijing, China].

With increasing urbanization, the stream ecosystem in Beijing has faced great challenges. Phytoplankton, benthic macroinvertebrates, and water quality were investigated based on 25 sampling sites in the North Canal River basin in July 2015, and the quality of the habitat was assessed in situ. A total of 22 metrics, including aquatic organism, hydrology, water quality, and habitat, were calculated to be the candidate indicators.

Estimating parameters of the variable infiltration capacity model using ant colony optimization.

Because hydrological models are so important for addressing environmental problems, parameter calibration is a fundamental task for applying them. A broadly used method for obtaining model parameters for the past 20 years is the evolutionary algorithm. This approach can estimate a set of unknown model parameters by simulating the evolution process.

[Effect of environmental factors on macroinvertebrate community structure in the Huntai River basin in the Huntai River basin].

In May-June 2012, macroinvertebrates were investigated at 66 sampling sites in the Huntai River basin in Northeast of China. A total of 72 macrobenthos species were collected, of which, 51 species (70.83%) were aquatic insects, 10 species (13.

[Effect of environmental factors on fish community structure in the Huntai River Basin at multiple scales].

In June 2012, fishes was investigated at 65 sampling sites in the Huntai River basin in Northeast of China. Forty species were collected, belonging to 9 orders, 14 families,33 genera. Cobitidae and Cyprinidae were the dominant fishes in the community structure in the Huntai River basin, accounting for 13.

[Estimation of nonpoint source pollutant loads and optimization of the best management practices (BMPs) in the Zhangweinan River basin].

One of the key techniques in establishing and implementing TMDL (total maximum daily load) is to utilize hydrological model to quantify non-point source pollutant loads, establish BMPs scenarios, reduce non-point source pollutant loads. Non-point source pollutant loads under different years (wet, normal and dry year) were estimated by using SWAT model in the Zhangweinan River basin, spatial distribution characteristics of non-point source pollutant loads were analyzed on the basis of the simulation result. During wet years, total nitrogen (TN) and total phosphorus (TP) accounted for 0.

[Macrobenthos community structure and its relationships with environmental factors in Weihe River basin, Northwest China].

In October 2011, an investigation was conducted on the macrobenthos at 45 sampling sites in the Weihe River basin of Northwest China. A total of 116 macrobenthos species were collected, of which, 91 species (78.4%) were aquatic insects, 12 species (10.

[Transport processes of low-level radioactive liquid effluent of nuclear power station in closed water body].

The transport processes of low-level radioactive liquid effluent of Xianning nuclear power station in the closed water body Fushui Reservoir are simulated using the EFDC model. Six nuclides concentration distribution with different half-lives in the reservoir are analyzed under the condition of 97% guarantee rate incoming water and four-running nuclear power units. The results show that the nuclides concentration distribution is mainly affected by the flow field of the reservoir and the concentration is decided by the half-lives of nuclide and the volume of incoming water.

[Spatiotemporal variation analysis and identification of water pollution sources in the Zhangweinan River basin].

In this study, several statistical methods including cluster analysis, seasonal Kendall test, factor analysis/principal component analysis and principal component regression were used to evaluate the spatiotemporal variation of water quality and identify the sources of water pollution in the Zhangweinan River basin. Results of spatial cluster analysis and principal component analysis indicated that the Zhangweinan River basin can be classified into two regions. One is the Zhang River upstream located in the northwest of the Zhangweinan River basin where water quality is good.

[Relationship between groundwater quality index of nutrition element and organic matter in riparian zone and water quality in river].

Riparian zone hydrology is dominated by shallow groundwater with complex interactions between groundwater and surface water. There are obvious relations of discharge and recharge between groundwater and surface water. Flood is an important hydrological incident that affects groundwater quality in riparian zone.

[Relationship between groundwater quality index of physics and chemistry in riparian zone and water quality in river].

Riparian zone hydrology is dominated by shallow groundwater with complex interactions between groundwater and surface water. There are obvious relations of discharge and recharge between groundwater and surface water. Flood is an important hydrological incident that affects groundwater quality in riparian zone.

[Relationship between groundwater level in riparian wetlands and water level in the river].

The development and degradation processes of riparian wetlands are significantly affected by river hydrological processes. By observing the variation of groundwater levels in riparian wetlands at the Kouma section of the Yellow River Wetland, especially that during the period of regulation for water and sediment at the Xiaolangdi Reservoir, relationship between groundwater level in riparian wetlands and flood water level in the river is studied. The results show that groundwater level in riparian wetlands is significantly affected by water level in the river investigated.