Download or read book Nutrient concentrations in surface water and groundwater and nitrate source identification using stable isotope analysis in the Barnegat Bay Little Egg Harbor Watershed New Jersey 2010 11 written by Christine Wieben and published by CreateSpace. This book was released on 2013 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: Five streams in the Barnegat Bay-Little Egg Harbor (BB- LEH) watershed in southern New Jersey were sampled for nutrient concentrations and stable isotope composition under base-flow and stormflow conditions, and during the growing and nongrowing seasons, to help quantify and identify sources of nutrient loading. Samples were analyzed for concentrations of total nitrogen, ammonia, nitrate plus nitrite, organic nitro- gen, total phosphorus, and orthophosphate, and for nitrogen and oxygen stable isotope ratios. Concentrations of total nitrogen in the five streams appear to be related to land use, such that streams in subbasins characterized by extensive urban development (and histori- cal agricultural land use)-North Branch Metedeconk and Toms Rivers-exhibited the highest total nitrogen concentra- tions (0.84-1.36 milligrams per liter (mg/L) in base flow). Base-flow total nitrogen concentrations in these two streams were dominated by nitrate; nitrate concentrations decreased during storm events as a result of dilution by storm runoff.
Download or read book Nutrient Concentrations in Surface Water and Groundwater and Nitrate Source Iden Tification Using Stable Isotope Analysis in the Barnegat Bay Little Egg Harbor Water Shed New Jersey 2010 11 written by Christine Wieben and published by Createspace Independent Publishing Platform. This book was released on 2014-08 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Five streams in the Barnegat Bay-Little Egg Harbor (BB- LEH) watershed in southern New Jersey were sampled for nutrient concentrations and stable isotope composition under base-flow and stormflow conditions, and during the growing and nongrowing seasons, to help quantify and identify sources of nutrient loading. Samples were analyzed for concentrations of total nitrogen, ammonia, nitrate plus nitrite, organic nitro- gen, total phosphorus, and orthophosphate, and for nitrogen and oxygen stable isotope ratios. Concentrations of total nitrogen in the five streams appear to be related to land use, such that streams in subbasins characterized by extensive urban development (and histori- cal agricultural land use)-North Branch Metedeconk and Toms Rivers-exhibited the highest total nitrogen concentra- tions (0.84-1.36 milligrams per liter (mg/L) in base flow). Base-flow total nitrogen concentrations in these two streams were dominated by nitrate; nitrate concentrations decreased during storm events as a result of dilution by storm runoff.
Download or read book Identifying Sources of Subsurface Nitrate Pollution with Stable Nitrogen Isotopes written by Timothy J. Wolterink and published by . This book was released on 1979 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of Nitrate Sources Using Nitrogen isotope Techniques in Shallow Ground Water Within Selected Lake Basins in the Central Lakes District Polk and Highlands Counties Florida written by Ann B. Tihansky and published by . This book was released on 1997 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Use of Stable Isotopes of Carbon Nitrogen and Sulfur to Identify Sources of Nitrogen in Surface Waters in the Lower Susquehanna River Basin Pennsylvania written by Charles A. Cravotta and published by . This book was released on 2002 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Concentrations Loads and Yields of Total Nitrogen and Total Phosphorus in the Barnegat Bay Little Egg Harbor Watershed New Jersey 1989 2011 at Multiple Spatial Scales written by Ronald J. Baker and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nutrients in the Nation s Waters written by David K. Mueller and published by . This book was released on 1996 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nutrients in water are necessary for productive aquatic ecosystems, but in high concentrations, nutrients such as nitrates, ammonia, and phosphates can adversely affect aquatic life and human health.
Download or read book Probability of Detecting Elevated Concentrations of Nitrate in Ground Water in a Six county Area of South central Idaho written by Kenneth D. Skinner and published by . This book was released on 2003 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Relation of Nitrogen and Phosphorus in Ground Water to Land Use in Four Subunits of the Potomac River Basin written by Scott W. Ator and published by . This book was released on 1997 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nutrient Criteria Technical Guidance Manual written by and published by . This book was released on 2000 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nitrate Source Evaluation of Surface Water and Groundwater in the Franklin Area Using a Dual Stable Isotope Approach written by Karyne Rogers and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific Investigations Report written by Sharon E. Kroening and published by . This book was released on 2004 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sources of Groundwater Nitrate Revealed Using Residence Time and Isotope Methods written by and published by . This book was released on 2004 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitrate concentrations approaching and greater than the maximum contaminant level (MCL) are impairing the viability of many groundwater basins as drinking water sources. Nitrate isotope data are effective in determining contaminant sources, especially when combined with other isotopic tracers such as stable isotopes of water and tritium-helium ages to give insight into the routes and timing of nitrate inputs to the flow system. This combination of techniques is demonstrated in Livermore, CA, where it is determined that low nitrate reclaimed wastewater predominates in the northwest, while two flowpaths with distinct nitrate sources originate in the southeast. Along the eastern flowpath, [delta]15N values greater than 10{per_thousand} indicate that animal waste is the primary source. Diminishing concentrations over time suggest that contamination results from historical land use practices. The other flowpath begins in an area where rapid recharge, primarily of low-nitrate imported water (identified by stable isotopes of water and a tritium-helium residence time of less than 1 year), mobilizes a significant local nitrate source, bringing groundwater concentrations up to 53 mg NO3 L−1. In this area, artificial recharge of imported water via local arroyos increases the flux of nitrate to the regional aquifer. The low [delta]15N value (3.1{per_thousand}) in this location implicates synthetic fertilizer. In addition to these anthropogenic sources, natural nitrate background levels between 15 and 20 mg NO3 L−1 are found in deep wells with residence times greater than 50 years.
Download or read book Multi decade Comparison of Groundwater Nitrate in the Southern Nottawasaga River Watershed written by Natalie Senger and published by . This book was released on 2016 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Nottawasaga River Watershed is host to the Lake Algonquin Sand Aquifer (LASA), an unconfined aquifer that consists of glaciolacustrine sands and provides water supply to rural residents, for household use, and for applications in agriculture. Previous studies, conducted between 1979 and 1983, measured nitrate in the LASA, and found concentrations that greatly exceeded the drinking water limit (10 mgN/L) and were measured as high as 103 mgN/L (Hill, 1982; Starr, et al., 1987). In these studies, groundwater was tested in domestic wells, groundwater seeps, and multi-level wells situated among agricultural fields. The historically high nitrate in the LASA was linked to agricultural activities, specifically those most focused on potato farming (Hill, 1982). Further to this, a lack of labile organic carbon (LOC) in the aquifer sediments, which acts as an electron donor for denitrification, the natural N cycling process responsible for converting nitrate to harmless N2 gas (Starr & Gillham, 1993). As part of the current study, nitrate was measured in domestic wells, groundwater seeps, and multi-level wells in 2010 and 2011, to compare the relative change in nitrate in the LASA over that past ~30 years. Statistical differences between the historical and current sample groups were evaluated using a Mann-Whitney rank-sum test for the domestic wells and groundwater seeps. Both of the groups were statistically different between the two dates, however, domestic wells were lower and groundwater seeps were higher, in nitrate. Multi-level wells showed varied results for comparing nitrate with those sampled in 1982 and 1983. Samples within a few meters of the water table had the most distinct changes in nitrate, whereas samples at depth were relatively similar. Increases in nitrate in MC2 could be attributed to the removal of a woodlot and subsequent cultivation which occurred in 2005. The depression of the water table also resulted in a change in the source for set sample points in MC4 and resulted in lower groundwater nitrate than historically measured. The depression of the water table also introduced oxygen and nitrate rich waters to greater depths below the ground surface than what was previously measured. Overall, the mean concentration of nitrate in the multi-level wells was less than the historical data. The decrease in nitrate for the domestic wells and multi-level wells might be related to changes in land management practices over the past three decades. Source identification for nitrate was constrained with the use of nitrate isotope ratios and artificial sweeteners. Domestic wells, groundwater seeps, and multi-level wells were all dominantly identified as nitrified chemical fertilizer, according to the dual isotope plot of nitrate. Artificial sweeteners were detected in 31% and 35% of the domestic wells and groundwater seeps, respectively, and were excellent tracers for septic wastewater. Further investigation into the proportion of nitrate derived from wastewater showed that septic systems contributed poorly to the nitrate pool in the LASA. Oxic conditions extended several meters below the water table in the LASA and provided conditions where nitrate could exist at high concentrations. Nitrate removal via denitrification was evident in all datasets, however it was often incomplete and did not remove nitrate entirely. The production of N2O in domestic wells and multi-level wells was generally attributed to denitrification in oxygenated groundwaters. In domestic wells, where nitrate was not present, and at the deepest sample points in the multi-level wells, redox conditions were classified having undergone nitrate, sulfate, and iron reduction. However, multi-level well data outlines that this occurs at depths of at least 15m below the water table. Groundwater seeps were less reduced and did not show evidence for sulfate or iron reduction. Therefore, the capacity of the aquifer to remove nitrate is not sufficient to cope with the amount of nitrate leached from agricultural practices.
Download or read book Application of Nitrogen Stable Isotopes to Identify Sources of Nutrient Pollution written by Elizabeth A. Redon and published by . This book was released on 2001 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nutrient pollution may perhaps be one of the oldest water quality problems and has recently been considered as one of the greatest threats to estuarine and coastal waters. Excessive nutrient loads have had a vast array of impacts on estuarine and coastal ecosystems globally. Direct negative effects include: shading out of benthic plant communities, hypoxia and anoxia due to increased biological oxygen demand, compositional change in plant and fauna! community structure and increased occurrences of harmful algal blooms. This has lead to decreased biodiversity, habitat, fisheries, tourism and aesthetics. So far environmental managers have had to rely on a posteriori assessments of the status of nutrient pollution, using indicators such as taxonomic shifts and changes in biological abundance, which have already occurred. By the time nutrient pollution is detected, restoration of habitats is costly and sometimes no longer an option. Therefore, there is a need for management tools to assess sources of nutrient loads before damage to estuarine and coastal ecosystems progresses beyond recovery. Early work using stable isotopes of dissolved inorganic nitrogen in groundwater samples demonstrated the potential for using stable isotopes to identify anthropogenic sources of nitrogen. These studies revealed that nitrogen sources such as fertilizers, soil organic nitrogen and wastewater nitrogen have isotopically distinct signatures that could be used to assess anthropogenic nitrogen contributions. Therefore, application of nitrogen stable isotope methods could potentially provide information on the anthropogenic nitrogen sources stimulating nutrient pollution in estuarine and coastal waters. However, when I assessed this approach for application, two sources of errors became apparent. First, laboratory isolation of dissolved inorganic nitrate from seawater delivered results depleted in 15N relative to the standard used to assess the method. Second, isotopic fractionation associated with nitrogen cycle processes complicates usage of an isotopic mass balance to solve for the nitrogen source and its fractional contribution based on isotopic data alone. As a result, isotopic analysis alone of dissolved inorganic nitrogen to determine anthropogenic sources of nutrient loads to estuarine and coastal waters is not a practical approach to obtain management information concerning nutrient pollution.
Download or read book Using Stable Isotopes to Develop a Regional Hydrogeological Model and Characterize Nitrate Sources in Groundwater written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Semi-arid regions, like the Okanagan Basin of British Columbia, Canada, are often faced with the difficulty of managing limited groundwater and surface water resources while accommodating rapid population growth and increasing land development. In the South Okanagan Basin, a better understanding of groundwater recharge sources, groundwater availability and susceptibility of water supplies to anthropogenic contamination is needed to best direct and protect the regions water resources. The purpose of this study was: (1) to characterize the regional hydrogeological setting of the South Okanagan Basin by establishing an isotopic and geochemical framework that included precipitation and surface waters of the Okanagan Basin and groundwaters of the South Okanagan Basin; and (2) to characterize nitrate contamination and its sources in shallow groundwaters of the Osoyoos area. Stable isotopes of water, nitrate and dissolved oxygen, groundwater chemistry, water levels and enriched tritium, tritium/helium and/or radiocarbon age dating techniques were used. Two provisional local meteoric water lines were established for the Okanagan Basin: & delta2H=6.06 & delta18O31.21 (Osoyoos) and & delta2H=7.03 & delta18O-12.68 (West Kelowna). Surface waters of the Okanagan River system were sources of irrigation water in the South Okanagan Basin valley and irrigation-return flow was the primary source of recharge for shallow groundwaters. Fractured bedrock in highlands east and west of the valley were not a significant source of recharge for shallow valley groundwater, however, may recharge deeper, or basal, valley deposits. As irrigation-return flow controls shallow groundwater dynamics in the valley sediments, groundwater quality is susceptible to anthropogenic contamination. In Osoyoos, nitrate was present in shallow groundwaters at concentrations of up to 24.4 mg/l N as a result of fertilizer nitrogen applied at the soil surface, mostly at orchards. Two agricultural drainage systems in north.
Download or read book Determining Sources of Nitrate in the Semi arid Rio Grande Using Nitrogen and Oxygen Isotopes written by Diego Alberto Sanchez Hernandez and published by . This book was released on 2017 with total page 105 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Rio Grande, a semi-arid river in the American Southwest, is a major source of surface water for agriculture and drinking supplies in New Mexico and Texas. In addition to increasing salinity, considerable increases of NO3− [nitrate] have been observed in the semi-arid portion of the Rio Grande. It is possible that elevated water salinity inhibits denitrification on irrigated fields and, thus, fails to mediate excess nutrient load from anthropogenic activities. Therefore, two major goals of this project were to 1) characterize and quantify major NO3− sources, and 2) assess whether elevated water salinity affects microbial denitrification. In fall 2014 and summer 2015, surface water, irrigation drains, urban runoff, and municipal waste effluents were sampled between Elephant Butte, New Mexico and Tornillo, Texas for stable isotope analysis. Highest NO3− concentrations were observed in waste effluents and nearby agricultural drains irrigated with reclaimed water. Conversely, NO3− concentrations in river and agricultural drains were significantly lower in areas farther away from urban centers. Two major NO3− sources were identified using chemical and isotope tracers: fertilizers, with low [lower case delta]15N [delta fifteen nitrogen] and high [lower case delta]18O [delta eighteen oxygen] (average 0.6 and 18.3‰ [permille], respectively), and waste water effluents from cities, with high [lower case delta]15N and low [lower case delta]18O (average 10.5 and -5.1‰, respectively). According to nitrogen and oxygen isotope mass balance constraints, waste effluent-derived NO3− contribution was the smallest in upstream locations and accounted for up to 24-47% near Las Cruces compared to fertilizer-derived NO3−. Further downstream, effluent contributions increased and accounted for up to 41-77% between Las Cruces and El Paso. The highest fertilizer-derived NO3− contributions of 90-100% were measured in the agricultural district located below El Paso where reclaimed city water is commonly used for irrigation. Elevated salinity did not appear to control microbial denitrification. In fact, the strongest isotopic evidence of microbial denitrification was observed in water samples showing elevated salinity. Results suggest urban centers are important NO3− contributors into aquatic system of the watershed and microbial processes do not appear to significantly reduce NO3− loads from anthropogenic sources.
