Regional, Reconnaissance Scale AEM Surveys to Better Define Surface Water ‐ Groundwater Processes beneath Large Unregulated River Systems

2011 ◽  
Author(s):  
Andrew Fitzpatrick ◽  
Tim J. Munday ◽  
Louise Stelfox ◽  
Rebecca Doble ◽  
Glenn Harrington
Keyword(s):  
Surface Water ◽  
River Systems

Anthropogenic influence on surface water quality of the Nhue and Day sub-river systems in Vietnam

2009 ◽  
Vol 32 (3) ◽  
pp. 227-236 ◽  
Author(s):  
Pham Thi Minh Hanh ◽  
Suthipong Sthiannopkao ◽  
Kyoung-Woong Kim ◽  
Dang The Ba ◽  
Nguyen Quang Hung
Keyword(s):  
Water Quality ◽  
Surface Water ◽  
Surface Water Quality ◽  
Anthropogenic Influence ◽  
River Systems

Surface Water Resources and River Systems of Andhra Pradesh

2015 ◽  
Author(s):  
K. N. Prudhvi Raju ◽  
Shraban Sarkar ◽  
Manish Kumar Pandey ◽  
Shruti Keshari ◽  
Mukesh Vishwakarma ◽  
...  
Keyword(s):  
Surface Water ◽  
Water Resources ◽  
Andhra Pradesh ◽  
River Systems ◽  
Surface Water Resources

scholarly journals Longitudinal discontinuities in riverine greenhouse gas dynamics generated by dams and urban wastewater

2018 ◽  
Vol 15 (20) ◽  
pp. 6349-6369 ◽  
Author(s):  
Hyojin Jin ◽  
Tae Kyung Yoon ◽  
Most Shirina Begum ◽  
Eun-Ju Lee ◽  
Neung-Hwan Oh ◽  
...  
Keyword(s):  
Optical Properties ◽  
Surface Water ◽  
Agricultural Runoff ◽  
Treated Wastewater ◽  
Lower Reach ◽  
Urban Wastewater ◽  
Middle Reach ◽  
River Systems ◽  
Han River ◽  
Ch4 And N2o

Abstract. Surface water concentrations of CO2, CH4, and N2O have rarely been measured simultaneously in river systems modified by human activities, contributing to large uncertainties in estimating global riverine emissions of greenhouse gases (GHGs). Basin-wide surveys of the three GHGs were combined with a small number of measurements of C isotope ratios in dissolved organic matter (DOM), CO2, and CH4 in the Han River basin, South Korea, to examine how longitudinal patterns of the three gases and DOM are affected by four cascade dams along a middle section of the North Han River (hereafter termed “middle reach”) and treated wastewater discharged to the lower Han River (“lower reach”) traversing the Seoul metropolitan area. Monthly monitoring and two-season comparison were conducted at 6 and 15 sites, respectively, to measure surface water gas concentrations and ancillary water quality parameters including concentrations of dissolved organic carbon (DOC) and optical properties of DOM. The basin-wide surveys were complemented with a sampling cruise along the lower reach and synoptic samplings along an urban tributary delivering effluents from a large wastewater treatment plant (WWTP) to the lower reach. The levels of pCO2 were relatively low in the middle reach (51–2465 µatm), particularly at the four dam sites (51–761 µatm), compared with those found in the largely forested upper basin with scattered patches of croplands (163–2539 µatm), the lower reach (78–11298 µatm), and three urban tributaries (2120–11970 µatm). The upper and middle reaches displayed generally low concentration ranges of CH4 and N2O, with some local peaks influenced by agricultural runoff and impoundments. By comparison, the lower reach exhibited exceptionally high concentrations of CH4 (1.2–15766 nmol L−1) and N2O (7.5–1396 nmol L−1), which were significantly correlated with different sets of variables such as DO and PO43- for CH4 and NH4+ and NO3- for N2O. Downriver increases in the levels of DOC and optical properties such as fluorescence index (FI) and protein-like fluorescence indicated an increasing DOM fraction of anthropogenic and microbial origin. The concentrations of the three GHGs and DOC were similar in magnitude and temporal variation at a WWTP discharge and the receiving tributary, indicating a disproportionate contribution of the WWTP effluents to the tributary gas and DOC exports to the lower reach. The values of δ13C in surface water CO2 and CH4 measured during the sampling cruise along the lower reach, combined with δ13C and Δ14C in DOM sampled across the basin, implied a strong influence of the wastewater-derived gases and aged DOM delivered by the urban tributaries. The downstream enrichment of 13C in CO2 and CH4 suggested that the spatial distribution of these gases across the eutrophic lower reach may also be constrained by multiple concomitant processes including outgassing, photosynthesis, and CH4 oxidation. The overall results suggest that dams and urban wastewater may create longitudinal discontinuities in riverine metabolic processes leading to large spatial variations in the three GHGs correlating with different combinations of DOM properties and nutrients. Further research is required to evaluate the relative contributions of anthropogenic and in-stream sources of the three gases and DOM in eutrophic urbanized river systems and constrain key factors for the contrasting impoundment effects such as autotrophy-driven decreases in pCO2 and in-lake production of CH4 and N2O.

Investigation into the bacterial pollution levels at various sites along the Diep and Plankenburg river systems, 3 Western Cape, South Africa

2016 ◽  
Vol 73 (11) ◽  
pp. 2590-2599
Author(s):  
O. O. Alegbeleye ◽  
B. O. Opeolu ◽  
V. A. Jackson
Keyword(s):  
South Africa ◽  
Surface Water ◽  
Sampling Time ◽  
Western Cape ◽  
River Systems ◽  
Bacterial Counts ◽  
Sediment Samples ◽  
Microbial Counts ◽  
Water And Sediment ◽  
Water And Sediment Samples

This study sought to investigate and compare bacterial contamination levels at six different sites along the Diep and Plankenburg river systems in the Western Cape, South Africa. Surface water and sediment samples were collected monthly from the six selected sampling sites along both river courses between January 2014 and December 2014 and were evaluated for bacterial contaminants. Microbial isolation, characterisation and identification were done using conventional techniques (serial dilution, Gram staining, and biochemical testing) and molecular identification techniques (polymerase chain reaction and DNA sequencing). A total of 19 bacterial isolates belonging to the genera Raoultella, Bacillus, Pseudomonas, Klebsiella, Escherichia, Enterobacter, Exiguobacterium, Acinetobacter, Serratia, Aeromonas, Staphylococcus and Citrobacter were isolated from the surface water and sediment samples at the end of the survey. Higher microbial load was obtained from sediment samples compared to surface water samples. Seasonal variation was also observed in terms of microbial counts. Higher microbial counts were obtained during summer sampling time compared to winter sampling time. The most contaminated site was located on Plankenburg River with average bacterial counts ranging between 3.1 × 105–6.9 × 108 CFU/ml and 3.9 × 106–2.88 × 109 CFU/ml from surface water and sediment, respectively, recorded at this site during winter and summer. Although lower microbial counts were recorded along the Diep River course, most of the bacterial counts recorded along both rivers exceeded the acceptable maximum limits for river water.

Application of a Simple Cold Stub to the Direct Observation of Frozen Hydrated Sand

1973 ◽  
Vol 31 ◽  
pp. 212-213
Author(s):  
John M. Wehrung ◽  
Richard J. Harniman
Keyword(s):  
United States ◽  
Surface Water ◽  
Direct Observation ◽  
Controlled Study ◽  
Clay Particles ◽  
Organic Debris ◽  
Rock Formations ◽  
Water Tables ◽  
Permeable Rock ◽  
Natural Means

Water tables in aquifer regions of the southwest United States are dropping off at a rate which is greater than can be replaced by natural means. It is estimated that by 1985 wells will run dry in this region unless adequate artificial recharging can be accomplished. Recharging with surface water is limited by the plugging of permeable rock formations underground by clay particles and organic debris.A controlled study was initiated in which sand grains were used as the rock formation and water with known clay concentrations as the recharge media. The plugging mechanism was investigated by direct observation in the SEM of frozen hydrated sand samples from selected depths.

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