Relevant bibliographies by topics / Water quality and Nonpoint source pollution (NPS) / Dissertations / Theses

To see the other types of publications on this topic, follow the link: Water quality and Nonpoint source pollution (NPS).

Dissertations / Theses on the topic 'Water quality and Nonpoint source pollution (NPS)'

Author: Grafiati

Published: 4 June 2021

Last updated: 12 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 30 dissertations / theses for your research on the topic 'Water quality and Nonpoint source pollution (NPS).'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.

Rees, Gwendolen Jayne. "Two analyses of costs of agricultural NPS pollution: Transactions costs of expanding nutrient trading to agricultural working lands and Impacts of TCs and differential BMP adoption rates on the cost of reducing agricultural NPS pollution in Virginia." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/52939.

Full text

Abstract:

For over 30 years, federal and state governments have been engaged in a collective effort to improve the water quality and living resources in the Chesapeake Bay (CB), focusing particularly on reducing delivered nitrogen and phosphorus loads. However, achievement of water quality objectives remains elusive. In Virginia, agriculture represents the single largest source of nutrient loads to the Chesapeake Bay. Despite aggressive regulatory efforts in other nutrient source sectors, state authorities rely on educational programs and voluntary financial assistance programs to induce landowners to adopt best management practices (BMPs) that reduce agricultural nutrient loads. This study explores two economic aspects of efforts to reduce agricultural nonpoint source (NPS) pollution in the Virginia portion of the CB watershed. Firstly, current and possible future transactions costs associated with specific aspects of agricultural NPS participation in water quality trading (WQT) programs are examined in Chapter 1. A case study approach is used to consider the possible cost consequences of expanding the use of NPS credits from agricultural 'working lands' BMPs in Virginia. Findings indicate that overall transactions costs for nutrient trades involving agricultural NPS in Virginia are currently relatively low, due to the type of activities being credited: simple land conversions. Based on best available evidence, the administrative transactions costs of creating credits on agricultural 'working lands' using management and structural BMPs will be 2 to 5 times more costly on a per project basis than for credits generated from land conversions. Compliance monitoring protocols were found to be a significant driver of costs for credits generated from working agricultural lands. These results suggest an important cost/risk tradeoff between verification cost and compliance certainty for program designers to consider. The second study (Chapter 2) considers the economic cost of meeting pollution reduction targets for the Virginia portion of the CB Watershed. Existing cost models are based on simplifying behavioral assumptions about public transactions costs, conservation adoption rates, and implementation costs of agricultural BMPs. This study builds on the existing literature and uses the estimates of transactions costs from Chapter 1 together with information on producer BMP adoption rates to examine the implications of including transactions costs and differential BMP costs and adoption rates when estimating the minimum costs of achieving specified nutrient reduction goals in Virginia. The paper uses a cost-minimizing mathematical programming approach and models a number of different cost scenarios. Results indicate that inclusion of transactions costs substantially affects estimates of total costs of meeting nutrient reduction goals; on average total costs increased by 44 percent, but ranged between 19 and 81 percent depending on the scenario analyzed. Analysis of the modelled scenarios shows that those BMPs that account for the most implementation costs do not necessarily account for the most transactions costs (and vice versa). This suggests that transactions costs should be acknowledged to vary with the type of practices being implemented, rather than being approximated as either a fixed amount or a fixed proportion of implementation costs. In addition, the analysis highlights the disproportionate costs associated with achieving nutrient reductions via high-cost adopters, and suggests there may be a role for education or extension to assist landholders to lower opportunity costs of participating in conservation. Master of Science

APA, Harvard, Vancouver, ISO, and other styles

Padmanabhan, Aarthi. "Stormwater evaluation and site assessment : a multidisciplinary approach for stormwater Best Management Practices (BMPs)." Thesis, Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/1141.

Full text

APA, Harvard, Vancouver, ISO, and other styles

MacQueen, A. Andrew. "Spatial characterization of pollution sources an analysis of in-stream water quality data from the Potomac Headwaters of West Virginia /." Morgantown, W. Va. : [West Virginia University Libraries], 2005. https://etd.wvu.edu/etd/controller.jsp?moduleName=documentdata&jsp%5FetdId=3837.

Full text

Abstract:

Thesis (M.S.)--West Virginia University, 2005 Title from document title page. Document formatted into pages; contains vi, 113 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 107-113).

APA, Harvard, Vancouver, ISO, and other styles

Qiu, Zeyuan. "Integrated assessment of agricultural nonpoint source pollution in Goodwater Creek Watershed, Missouri /." free to MU campus, to others for purchase, 1996. http://wwwlib.umi.com/cr/mo/fullcit?p9821344.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Butler, Gary Brooks. "Evaluating water quality impacts of alternative management practices through development of a BMP database." Auburn, Ala., 2007. http://repo.lib.auburn.edu/2007%20Spring%20Theses/BUTLER_GARY_41.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Malone, Sarah J. "Agricultural nonpoint source pollution management : water quality impacts of Balm Road Treatment Marsh, Hillsborough County, Florida." [Tampa, Fla] : University of South Florida, 2009. http://purl.fcla.edu/usf/dc/et/SFE0003211.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Chingombe, Wisemen. "Effects of land-cover - land-use on water quality within the Kuils - Eerste River catchment." Thesis, University of Western Cape, 2012. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_5893_1373463134.

Full text

Abstract:

line-height:150% font-family:&quot Times New Roman&quot ,&quot serif&quot ">The most significant human impacts on the hydrological system are due to land-use change. The conversion of land to agricultural, mining, industrial, or residential uses significantly alters the hydrological characteristics of the land surface and modifies pathways and rates of water flow. If this occurs over large or critical areas of a catchment, it can have significant short and long-term impacts, on the quality of water. While there are methods available to quantify the pollutants in surface water, methods of linking non-point source pollution to water quality at catchment scale are lacking. Therefore, the research presented in this thesis investigated modelling techniques to estimate the effect of land-cover type on water quality. The main goal of the study was to contribute towards improving the understanding of how different land-covers in an urbanizing catchment affect surface water quality. The aim of the research presented in this thesis was to explain how the quality of surface runoff varies on different land-cover types and to provide guidelines for minimizing water pollution that may be occurring in the Kuils-Eerste River catchment. The research objectives were (1) to establish types and spatial distribution of land-cover types within the Kuils-Eerste River catchment, (2) to establish water quality characteristics of surface runoff from specific land-cover types at the experimental plot level, (3) to establish the contribution of each land-cover type to pollutant loads at the catchment scale. line-height:150% font-family:&quot Times New Roman&quot ,&quot serif&quot ">Land-cover characteristics and water quality were investigated using GIS and Remote Sensing tools. The application of these tools resulted in the development of a land-cover map with 36 land classifications covering the whole catchment. Land-cover in the catchment is predominantly agricultural with vineyards and grassland covering the northern section of the catchment. Vineyards occupy over 35% of the total area followed by fynbos (indigenous vegetation) (12.5 %), open hard rock area (5.8 %), riparian forest (5.2 %), mountain forest&nbsp &nbsp (5 %), dense scrub (4.4 %), and improved grassland (3.6 %). The residential area covers about 14 %. Roads cover 3.4 % of the total area. line-height:150% font-family:&quot Times New Roman&quot ,&quot serif&quot ">Surface runoff is responsible for the transportation of large quantities of pollutants that affect the quality of water in the Kuils-Eerste River catchment. The different land-cover types and the distribution and concentration levels of the pollutants are not uniform. Experimental work was conducted at plot scale to understand whether land-cover types differed in their contributions to the concentration of water quality attributes emerging from them. Four plots each with a length of 10 m to 12 m and 5 m width were set up. Plot I was set up on open grassland, Plot II represented the vineyards, Plot III covered the mountain forests, and Plot IV represented the fynbos land-cover. Soil samples analyzed from the experimental plots fell in the category of sandy soil (Sa) with the top layer of Plot IV (fynbos) having loamy sand (LmSa). The soil particle sizes range between fine sand (59.1 % and 78.9 %) to coarse sand (between 7 % and 22 %). The content of clay and silt was between 0.2 % and 2.4 %. Medium sand was between 10.7 % and 17.6 %. In terms of vertical distribution of the particle sizes, a general decrease with respect to the size of particles was noted from the top layer (15 cm) to the bottom layer (30 cm) for all categories of the particle sizes. There was variation in particle size with depth and location within the experimental plots.line-height:150% font-family:&quot Times New Roman&quot ,&quot serif&quot ">Two primary methods of collecting water samples were used grab sampling and composite sampling. The quality of water as represented by the samples collected during storm events during the rainfall season of 2006 and 2007 was&nbsp used to establish &nbsp water quality characteristics for the different land-cover types. The concentration of total average suspended solids was highest in the following land-cover types, cemeteries (5.06 mg L-1), arterial roads/main roads (3.94 mg L-1), low density residential informal squatter camps (3.21 mg L-1) and medium density residential informal townships (3.21 mg L-1). Chloride concentrations were high on the following land-cover types, recreation grass/ golf course (2.61 mg L-1), open area/barren land (1.59 mg L-1), and improved grassland/vegetation crop (1.57 mg L-1). The event mean concentration (EMC) values for NO3-N were high on commercial mercantile (6 mg L-1) and water channel (5 mg L-1). The total phosphorus concentration mean values recorded high values on improved grassland/vegetation crop (3.78 mg L-1), medium density residential informal townships (3mgL-1) and low density residential informal squatter camps (3 mg L-1). Surface runoff may also contribute soil particles into rivers during rainfall events, particularly from areas of disturbed soil, for example areas where market gardening is taking place. The study found that different land cover types contributed differently to nonpoint source pollution. line-height:150% font-family:&quot Times New Roman&quot ,&quot serif&quot ">A GIS model was used to estimate the diffuse pollution of five pollutants (chloride, phosphorus, TSS, nitrogen and NO3-N) in response to land cover variation using water quality data. The GIS model linked land cover information to diffuse nutrient signatures in response to surface runoff using the Curve Number method and EMC data were developed. Two models (RINSPE and N-SPECT) were used to estimate nonpoint source pollution using various GIS databases. The outputs from the GIS-based model were compared with recommended water quality standards. It was found that the RINSPE model gave accurate results in cases where NPS pollution dominate the total pollutant inputs over a given land cover type. However, the N-SPECT model simulations were too uncertain in cases where there were large numbers of land cover types with diverse NPS pollution load. All land-cover types with concentration values above the recommended national water quality standard were considered as areas that needed measures to mitigate the adverse effects of nonpoint pollution. line-height:150% font-family:&quot Times New Roman&quot ,&quot serif&quot ">The expansion of urban areas and agricultural land has a direct effect on land cover types within the catchment. The land cover changes have adverse effect which has a potential to contribute to pollution.

APA, Harvard, Vancouver, ISO, and other styles

Ubilava, Mariam. "Effect of winter storm on water quality and fish toxicity the Duwamish and Nisqually Rivers /." Online pdf file accessible through the World Wide Web, 2007. http://archives.evergreen.edu/masterstheses/Accession86-10MES/Ubilava_M%20MESThesis%202007.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Leitch, Katherine McArthur. "Estimating Tributary Phosphorus Loads Using Flow-Weighted Composite Storm Sampling." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/10078.

Full text

Abstract:

Quantification of total phosphorus (TP) loads entering a lake or reservoir is important because phosphorus is most often the limiting nutrient in terms of algae growth, thus phosphorus can control the extent of eutrophication. Four methods for assessing the annual tributary phosphorus loads to two different Virginia reservoirs were analyzed, three methods that use tributary monitoring program data and one that uses land-use and rainfall data. In this project, one tributary has been extensively monitored for many years and served as a control on which the other methods were tested. The key difference between this research and previous studies is the inclusion of flow-weighted composite storm sampling instead of simple grab sample analyses of storm flow. Three of the methods employed flow stratification, and the impact of the base flow separation point was examined. It was found that the Regression Method developed in this research was the least sensitive to the base flow separation point, which is a valuable attribute because a wrong choice will not significantly affect the estimate. The Monte Carlo Method was found to underestimate the TP loads. The amount of rainfall impacted the accuracy of the methods, with more error occurring in a year with lower precipitation. Master of Science

APA, Harvard, Vancouver, ISO, and other styles

Taylor, Michael A. "Tradable permit markets for the control of point and nonpoint sources of water pollution technology-based collective performance-based approaches /." Columbus, Ohio : Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1059077005.

Full text

Abstract:

Thesis (Ph. D.)--Ohio State University, 2003. Title from first page of PDF file. Document formatted into pages; contains xi, 465 p.; also includes graphics. Includes abstract and vita. Advisor: Allan Randall, Interdisciplinary Program. Includes bibliographical references (p. 161-165).

APA, Harvard, Vancouver, ISO, and other styles

Frazee, Joseph W. "Effects of forest harvesting best management practices on surface water quality in the Virginia coastal plain." Thesis, This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-09042008-063552/.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Singh, Rajesh Kumar. "Identification of critical areas of non-point source pollution from flat agricultural watersheds." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ37167.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Secoges, Joseph Michael. "Nutrient Movement in Streamside Management Zones and Piedmont Streams Following Forest Fertilization." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/33497.

Full text

Abstract:

Many statesâ Best Management Practices (BMP) programs established Streamside Management Zone (SMZ) widths based on limited or inadequate data with regard to nutrient fluxes from silvicultural activities. Previous studies in forested watersheds have shown slight post-harvest increases of several nutrients in streams. Also, in agricultural settings, increased nitrogen (N) and phosphorous (P) levels have been detected in streams. However, little is known about the effectiveness of recommended forested SMZ widths for controlling nutrient fluxes following fertilizer application. Diammonium phosphate (DAP) and urea fertilizers were applied to subwatersheds of 2 to 3 year-old loblolly pine (Pinus taeda L.) plantations upslope from SMZ study areas throughout Buckingham Co., VA. Three replications of four SMZ treatment widths (30.5m, 15.2m, and 7.6m plus a thinned 15.2m SMZ) were studied using surface water collectors, cation/anion exchange membranes, lysimeters, and stream grab-samples. Measurement devices were spaced symmetrically across the SMZ from the uphill SMZ edge to stream edge with grab samples being collected approximately 20m upstream and 20m downstream of the fertilized area. Little nitrogen and phosphorous movement was detected in surface water which was monitored using surface water collectors. Near-surface water flow sampling using ionic exchange membranes resulted in our most complete dataset and showed infrequent lateral ion transport in the litter and upper soil layers even after water passed over an approximately 1m wide, seeded firebreak located between the SMZ dripline and fertilized area. Results from lysimeter samples used to measure subsurface flow were limited due to dry conditions; however, the limited samples indicate that only minute levels of nitrogen and phosphorous are transported laterally via shallow subsurface and surface flow. Overall, sampling indicated that only minute quantities of nitrogen and phosphorous were ever transported from the fertilized clearcut to the riparian area. Results indicate that even a 7.6m wide SMZ with a seeded firebreak is adequate to protect streams from industrial fertilizer application in a relatively dry year, but wider SMZs may be necessary for other benefits. Master of Science

APA, Harvard, Vancouver, ISO, and other styles

Persaud, Ann Rebecca. "Still Waters Run Deep: Landscaping Practices, Community Perceptions, and Social Indicators for Stormwater Nonpoint Source Pollution Management in Manatee County, Florida." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5102.

Full text

Abstract:

Stormwater nonpoint source pollution (NPSP) is a result of diffuse sources of pollutants transported by rainfall and surface runoff into stormwater ponds and drainage systems before percolating into the ground. In particular, the nutrients found in fertilizers, pesticides, and herbicides applied in excess by homeowners and landscapers can cause a range of issues in stormwater ponds from fish kills to eutrophication. As a result, Manatee County, Florida has issued a fertilizer ordinance with best management practices (BMPs) and a fertilizer black out period to reduce NPSP. This study is aimed at capturing the perceptions of residents which affect stormwater NPSP through their behaviors, awareness, and knowledge. Interviews, surveys,and observational data were used to establish social indicator scores, gather qualitative data, and evaluate outreach efforts surrounding the Manatee County fertilizer ordinance and the function stormwater ponds in Lakewood Ranch. Results showed that residents substantially lacked awareness of the fertilizer ban, ordinance and grass clipping violation fine. Outreach questions revealed that 69% of residents had not seen any materials related to the ban. While residents' feelings generally ranged from neutral to positive with regard to shoreline and aquatic plants, they remained resistant to the actual installation of the plants. The results also indicated that residents were well aware of the purposes shoreline plants serving as barriers and nutrient filters. In addition, Key Informant interviews revealed that while residents understood the environmental consequences of their actions, they maintained their behavior to adhere to deeply rooted social norms.

APA, Harvard, Vancouver, ISO, and other styles

Mendez-Delgado, Aida. "Nitrogen transport and dynamics in grass filter strips." Diss., Virginia Tech, 1996. http://hdl.handle.net/10919/39047.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Cristan, Richard. "Effectiveness of State Developed and Implemented Forestry Best Management Practices in the United States." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/71657.

Full text

Abstract:

The passage of the Federal Water Pollution Control Act of 1972 required states to develop forestry BMPs to help reduce potential nonpoint source pollution from forest operations. Properly applied forestry best management practices (BMPs) have since been proven to protect water quality from forest operations. This research project reviewed BMP effectiveness studies in the U.S., assessed current state developed and implemented of forestry BMPs, and developed a simple method to estimate potential erosion from forest operations for the Piedmont physiographic region based on previous studies. Eighty-one BMP effectiveness studies were reviewed. The review of past effectiveness studies indicates that water quality protection is increased when BMPs are implemented correctly. These effectiveness studies provide states with valuable information on how their BMP guidelines are achieving the goals defined by the Federal Water Pollution Control Act. Every U.S. state has forestry BMP guidelines. These guidelines may be non-regulatory, quasi-regulatory, or regulatory depending on the state. Twenty states reported implementing non-regulatory BMP guidelines, 19 quasi-regulatory BMP guidelines, and 11 regulatory BMP guidelines. State forestry agencies were reported as being the lead agency responsible for BMP monitoring in 35 states. The national forestry BMP implementation rate was 91% (32 states). However, states did report deficiencies for specific BMP guideline categories. Supplementary to the reviewed BMP effectiveness studies, forest erosion studies in the southeastern U.S. that quantified erosion rates from forest operations were also reviewed. Erosion rates obtained from the literature were reviewed by operation categories (timber harvesting, forest roads, skid trails, log landings, stream crossings, and streamside management zones) and physiographic region (Mountains, Piedmont, Gulf Coastal Plain, and Atlantic Coastal Plain). There were numerous research gaps regarding erosion rates from forest operations for all the regions except the Piedmont region. The Piedmont region was selected for developing a method to estimate potential erosion from forest operations. This erosion estimation method is a quick and potentially useful tool for estimating potential erosion; however, it is based on limited data from the Piedmont region only. The basic method approach might be considered for the other physiographic regions, but further research is needed to fill current knowledge gaps. Ph. D.

APA, Harvard, Vancouver, ISO, and other styles

Chen, Wei-Bin. "Optimal allocation of stormwater pollution control technologies in a watershed." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1158464967.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Lapp, Paul 1968. "The hydrology and water quality of an intensive agricultural watershed in Quebec." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23906.

Full text

Abstract:

A research project was undertaken to study the hydrology and water quality of a 26 km$ sp2$ intensive agricultural watershed over an 18 month period. Flow and precipitation data were used to establish hydrologic parameters for the watershed and to empirically model hydrologic processes. Water samples taken from the outlet of the watershed were analyzed for nitrate, phosphate, suspended sediment and atrazine. Water quality data were analyzed to establish temporal trends in pollutant concentration and load in the watercourse. The measured time of concentration was found to be consistent with a mean of 6.89 hours for the 25 storms profiled. The time to peak was found to vary linearly with storm duration. The event recession constant was measured to be 0.9715. Regression analysis was performed on measured hydrologic properties. The strongest relationship was found between the percentage of rainfall appearing as runoff versus the sum of the 72 hour antecedent rainfall plus the storm rainfall. Spring snowmelt was identified as a significant period of pollutant material export. All pollutant materials displayed seasonal variability in the export process. Temporal variability accounted for poor correlations between observed hydrologic and water quality parameters in the two seasons for which data were available. Peak pollutant concentrations were associated with high flow events. Maximum observed concentrations for nitrate, phosphate, suspended sediment and atrazine were 8.6 mg/l, 0.478 mg/l, 0.7 g/l, and 8.06 ug/l respectively.

APA, Harvard, Vancouver, ISO, and other styles

Johnston, Carey Andrew. "Development and Evaluation of Infilling Methods for Missing Hydrologic and Chemical Watershed Monitoring Data." Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/10028.

Full text

Abstract:

Watershed monitoring programs generally do not have perfect data collection success rates due to a variety of field and laboratory factors. A major source of error in many stream-gaging records is lost or missing data caused by malfunctioning stream-side equipment. Studies estimate that between 5 and 20 percent of stream-gaging data may be marked as missing for one reason or another. Reconstructing or infilling missing data methods generate larger sets of data. These larger data sets generally generate better estimates of the sampled parameter and permit practical applications of the data in hydrologic or water quality calculations. This study utilizes data from a watershed monitoring program operating in the Northern Virginia area to: (1) identify and summarize the major reasons for the occurrence of missing data; (2) provide recommendations for reducing the occurrence of missing data; (3) describe methods for infilling missing chemical data; (4) develop and evaluate methods for infilling values to replace missing chemical data; and (5) recommend different infilling methods for various conditions. An evaluation of different infilling methods for chemical data over a variety of factors (e.g., amount of annual rainfall, whether the missing chemical parameter is strongly correlated with flow, amount of missing data) is performed using Monte Carlo modeling. Using the results of the Monte Carlo modeling, a Decision Support System (DSS) is developed for easy application of the most appropriate infilling method. Master of Science

APA, Harvard, Vancouver, ISO, and other styles

Matji, Maselaganye Petrus. "Comparative modelling of phosphorous production in rural catchments." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51657.

Full text

Abstract:

Thesis (M.Ing.)--Stellenbosch University, 2000. ENGLISH ABSTRACT: The objective of this research has been to compare nonpoint sources assessment techniques for simulating phosphorous production in rural catchments which have a variety ofland use types. Four nonpoint source assessment techniques capable of simulating phosphorous production, operating at different spatial and temporal resolutions, were selected after an intensive literature review. The model selection criteria included the capability to simulate phosphorous production, the need for the study to cover a range of spatial and temporal resolutions, model data requirements, model affordability and availability in South Africa. The models selected using these criteria are the Phosphorous Export Model (PEM) (Weddepohl & Meyer, 1992), Impoundment and River Management and Planning Assessment Tool for Water Quality Simulation Model (IMPAQ) (DWAF,1995), the Hydrological Simulation Program Fortran (HSPF) (Bricknell,1993) and the Agricultural Catchments Research Unit Model (ACRU) (Smithers and Caldecott, 1994). Four ofthe study catchments were selected within the Berg River basin in the Western Cape and the remaining four were selected within the Amatole catchments in the Eastern Cape. The four subcatchments in the Berg River basin are the Twenty-Four Rivers, Leeu River, Kompanjies River and Doring River catchments and the four in the Amatole catchments are the Upper Buffalo, Cwencwe, Yellowwoods and Gqunube River catchments. The range of land use/cover types comprises: Western Cape catchments : wheat, grapes, natural vegetation and forestry Eastern Cape catchments : natural vegetation and forestry The PEM and IMPAQ models were applied reasonably successfully to all the catchments to simulate phosphorous production, with the observed flow as the input. The HSPF model could not successfully be applied to the catchments to simulate both the catchment hydrology and phosphorous production. Hence, the investigation into HSPF was abandoned, and in its place, the ACRU daily phosphorous yield model was incorporated at a fairly late stage in the research. ACRU was applied to only the Western Cape catchments. The estimated parameters for different land use types were compared to investigate the potential for parameter transfer in space and time. Both the PEM and IMP AQ models showed promise that land use parameters could be transferred in time for catchments located in the Western Cape catchments, but did not show promise for catchments located in the Eastern Cape. The IMPAQ model showed promise that land use parameters could be transferred in space for catchments located in the Eastern Cape, but did not perform as well in the Western Cape catchments. The PEM model showed promise that land use parameters could be transferred in space for catchments located in the Western Cape, but did not perform as well in the Eastern Cape. Since the ACRU phosphorous yield model was included at a late stage of the research, the potential for land use parameter transfer in space and time could not investigated. The model results were verified at the relevant flow and water quality gauging stations. The ACRU phosphorous model verification results showed promise for catchments located in humid parts of the Berg River basin, but did not perform as well in the catchment located in the semi-arid part. RECOMMENDATIONS FOR FURTHER RESEARCH: I. Intensive research should be undertaken to develop a database ofland use parameters/ export coefficients related to phosphorous production (and other non-conservative constituents) in South African catchments. Availability of these parameters would make phosphorous modelling much easier. HSPF should be configured and calibrated, more especially its water quality component, for catchments with hourly rainfall and rainfall stations located within/on the catchment boundaries, to investigate its performance under South African conditions. Given the complexity of the HSPF algorithms and the time required to familiarise oneself with the model, it is recommended that such an investigation be undertaken which is not inclusive of any other models. The spatial resolution ofPEM is extremely coarse, and should be improved to allow the user to partition the total flow in the catchment according to contributions from the variety ofland use types and to estimate soluble and particulate phosphorous parameters for each land use type. A study should be undertaken to investigate the potential for the ACRU phosphorous yield model parameter transfer in time and space. Sampling frequency of water quality data in South Africa should be improved, because it is difficult to assess the performance of the calibrated water quality models, more especially phosphorous export models, due to a lack of continuous data sets. Rainfall data collection in gauged catchments, more especially Western Cape catchments (e.g. Twenty-Four Rivers, Leeu, Kompanjies and the Doring River catchments), should be improved. There should be at least one rainfall gauging station located within the catchment boundaries. This would contribute towards achieving reasonable hydrological calibration or verification. Since runoff is the driving factor for water quality components, improved hydrological calibration/verification would result in reasonable water quality calibration/verification. AFRIKAANSE OPSOMMING: Die doel van die navorsing was om die simulering van fosfaat produksie in landelike gebiede, wat 'n verskeidenheid grondgebruike het, met behulp van nie-punt bron evaluerings tegnieke te evulaeer. Vier nie-punt bron evaluerings tegnieke, met die vermoë om fosfaat produksie op verskillende ruimtelike en tyds resolusies te simuleer, is gekies na 'n intensiewe ondersoek van beskikbare literatuur. Die kriteria vir die keuse van die model het ingesluit die vermoë om fosfaat produksie te simuleer, die behoefte vir die studie om 'n reeks van ruimtelike en tyds resolusies te simuleer, model data vereistes, model bekostigbaarheid en beskikbaarheid in Suid Afrika. Die gekose modelle, gebaseer op bogemelde kriteria, was die PEM, IMPAQ, HSPF en ACRU modelle. Vier van die opvanggebiede gebruik in die studie, was in die Bergrivier bekken in die Wes-Kaap en vier was in die Amatole opvanggebiede in die Oos-Kaap. Die vier opvanggebiede in die Bergrivier bekken is die Vier-en- Twentigriviere, Leeurivier, Kompanjiesrivier en die Doringrivier en die vier opvanggebiede in die Amatole opvanggebiede is die Bo-Buffels, Cwencwe, Yellowwoods, en die Gunubierivier opvanggebiede. Grondgebruik beslaan die volgende: Wes-Kaap opvanggebiede : koring, druiwe, natuurlike weiding en plantasies. Oos-Kaap : natuurlike plantegroei en plantasies Die PEM en IMPAQ modelle is met redelike sukses in al die opvanggebiede gebruik vir die simulasie van fosfaat produksie, met die waargenome vloei as invoer. Die HSPF model kan nie met enige sukses gebruik word om beide die opvanggebied hidrologie en fosfaat produksie, te simuleer nie. Die HSPF model is dus uitgeskakel en in 'n redelike laat stadium van die studie met die ACRU daaglikse fosfaat leweringsmodel vervang. Die ACRU model is net op die Wes-Kaap opvanggebiede toegepas. Die beraamde parameters vir die verskillende grondgebruik tipes is vergelyk om die potensiaal vir parameter oordrag in ruimte en tyd te ondersoek. Beide die PEM en IMPAQ modelle het belowend vertoon ten opsigte van die oordrag van grondgebruik parameters in tyd vir opvanggebiede in die Wes- Kaap, maar het geensins belowend vertoon vir die Oos-Kaap opvanggebiede nie. Die IMPAQ model het belowend vertoon ten opsigte van die ruimtelike oordrag van grondgebruik parameters vir die Oos-Kaap opvanggebiede, maar het nie so goed vertoon in die Wes-Kaap opvanggebiede nie. Die PEM model het belowend vertoon ten opsigte van die ruimtelike oordrag dat grondgebruikte parameters in die Wes-Kaap opvanggebiede is, maar het nie so goed in die Oos-Kaap opvanggebiede vertoon nie. Aangesien die ACRU fosfaat leweringsmodel op 'n laat stadium van die navorsing ingesluit is, kan die potensiaal vir die oordrag van grondgebruik parameters in ruimte en tyd nie ondersoek word nie. Die model resultate is by die toepaslike vloei en waterkwaliteit meetstasies geverifiëer Die resultate van die ACRU fosfaat model verifikasie het belowend vertoon vir opvangebiede in die humiede gedeeltes van die Bergrivier bekken, maar het nie so goed vertoon in die semi-droeë deel van die opvangebied nie. AANBEVELINGS VIR VERDERE NAVORSING : Y4 Intensiewe navorsing moet onderneem word ten einde in 'n databasis van grondgebruik parameters/oordrag koëffisiente met betrekking tot fosfaat produksie (en ander niekonserwatiewe bestandelle ) in Suid Afrikaanse opvanggebiede op te bou. Beskikbaarheid van hierdie parameters sal fosfaat modellering vergemaklik. Die HSPF model moet opgestel en gekalibreer word, meer spesifiek ten opsigte van die waterkwaliteit komponent, vir opvanggebiede met uurlikse reënval en reënvalstasies binne of op die opvanggebied grense, om die model se vertoning onder Suid Afrikaanse omstandighede te ondersoek. Gegewe die kompleksiteit van die HSPF algoritmes en tyd benodig om met model vertroud te raak, word dit aanbeveel dat so 'n ondersoek onderneem word met uitsluiting van die ander modelle. Die ruimtelike resolusie van die PEM model is uitermatig grof, en behoort verbeter te word ten einde die gebruiker toe te laat om die totale vloei in die opvanggebied in ooreenstemming met die bydraes van die onderskeie grondgebruik tipes te verdeel en om oplosbare en partikulere fosfaat parameters vir elke grondgebruik tipe te beraam. 'n Studie om die potensiaal vir die ruimtelike en tydsoordrag van die ACRU fosfaat leweringsmodel parameters te ondersoek, moet onderneem word. Die frekwensie van waterkwaliteit monitering in Suid Afrika moet verbeter word, aangesien dit moelik is om, weens 'n gebrek aan deurlopend waargenome data, die vertoning van gekalibreerde waterkwaliteit modelle te ondersoek, meer spesifiek nog fosfaat uitvoer modelle. Reënval inligting versameling in gemete opvanggebied, meer spesifiek die Wes-Kaap opvanggebiede (bv.Vier-en-Twintigriviere, Leeu, Kompanjies en Doringrivier opvanggebiede), behoort verbeter te word. Daar behoort ten minste een reënval stasie binne die opvanggebied grense te wees. Dit sal bydra tot die bereiking van redelike hidrologiese kalibrasie ofverifikasie. Aangesien afloop die dryfveer van die waterkwaliteit komponente is, sal verbeterde hidrologiese kalibrasie/verifikasie lei tot redelike waterkwaliteit kalibrasie/verifikasie.

APA, Harvard, Vancouver, ISO, and other styles

Brown, Kristopher Ryan. "Sediment Delivery from Reopened Forest Roads at Stream Crossings in the Virginia Piedmont Physiographic Region, USA." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/48424.

Full text

Abstract:

Efforts to control surface runoff and erosion from forest roads at stream crossings are critical for the protection of aquatic ecosystems in forests. In this research, annual and event-based sediment delivery rates were estimated for reopened legacy roads at forest stream crossings in the Virginia Piedmont physiographic region, USA. Sediment delivery rates were compared among stream crossing approaches with diverse intensities of best management practice (BMP) implementations for surface cover and water control. Model predictions from the Water Erosion Prediction Project (WEPP) were compared to field observations of surface runoff and sediment delivery to evaluate model performance. Annual sediment delivery rates from reopened (bare) legacy road approaches to stream crossings were 7.5 times higher than those of completely graveled approaches. Sediment delivery rates ranged from 34 to 287 Mg ha⁻¹ year⁻¹ for the bare approaches and from 10 to 16 Mg ha⁻¹ year⁻¹ for the graveled approaches. Event-based surface runoff and associated total suspended solids (TSS) concentrations were compared among a succession of gravel surfacing treatments that represented increasing intensities of BMP implementations on reopened approaches. The three treatments were No Gravel (10-19% cover), Low Gravel (34-60% cover), and High Gravel (50-99% cover). Median TSS concentration of surface runoff for the No Gravel treatment (2.84 g L⁻¹) was greater than Low Gravel (1.10 g L⁻¹) and High Gravel (0.82 g L⁻¹) by factors of 2.6 and 3.5, respectively. WEPP predictions of event-based sediment yield show clear differences among the different road surface treatments, but prediction intervals were wide, reflecting substantial prediction uncertainty. These findings show that reopened legacy roads and associated stream crossing approaches can deliver significant quantities of sediment if roads are not adequately closed or maintained and that corrective best management practices (BMPs), such as gravel and appropriate spacing of water control structures, can reduce sediment delivery to streams. Watershed management decisions that hinge upon WEPP predictions of sediment yield from forest roads must necessarily take into account a wide range of potential erosion rates for specific management scenarios. Ph. D.

APA, Harvard, Vancouver, ISO, and other styles

Ferreira, Sheila Cristhina da Rocha. "Estudo da qualidade dos corpos hídricos do Parque das Águas em Pinhais/PR." Universidade Tecnológica Federal do Paraná, 2012. http://repositorio.utfpr.edu.br/jspui/handle/1/479.

Full text

Abstract:

CAPES Os corpos hídricos têm suas características afetadas pela poluição difusa, por meio do carreamento de poluentes pelo escoamento superficial nos eventos de chuvas ou também por despejos pontuais. Esta pesquisa foi realizada nas cavas do Parque das Águas em Pinhais/PR e teve por objetivo avaliar a qualidade das águas e sedimentos dos corpos hídricos e a sua correlação com a poluição difusa. Foram analisadas algumas variáveis físico-químicas, bacteriológicas e de compostos orgânicos HPAs e n-Alcanos em 6 pontos, que podem indicar possíveis alterações na qualidade desses corpos hídricos. Estas cavas deverão futuramente ser destinadas para uso de recreação de contato secundário, como pesca e esportes náuticos pela LEI No 189/87 - Pinhais, indicando que as águas dessas cavas devem atender a resolução CONAMA 357/05, que estabelece limites para parâmetros físico- químicos, biológicos e de espécies metálicas que possam causar danos à saúde e ao ambiente. Para embasar a discussão dos resultados para HPAs e espécies metálicas em sedimento, utilizou-se a resolução CONAMA 344/04. Os limites indicados pelas resoluções do CONAMA 357/05 e 344/04, são valores de segurança. Com base nos resultados obtidos, identificou-se a influência das chuvas nas concentrações das variáveis analisadas. Através da comparação dos resultados com a Resolução CONAMA 357/05 para água doce de classe 2, pôde ser constatado que os parâmetros salinidade, OD, turbidez, amônia, nitrito, nitrato estão de acordo com os limites impostos pela resolução, a DBO a para maioria dos pontos analisados apresentou-se dentro dos limites, porém em um dos pontos excedeu o limite. Para Coliformes termotolerantes, a maior parte dos pontos se apresentou dentro dos limites estabelecidos pela resolução. A variável Sulfeto não atende a CONAMA 357/05. Dos sete metais analisados em água cádmio e ferro apresentam-se acima do limite para o CONAMA 357/05. Os metais cobre, zinco, cádmio, níquel e chumbo em sedimentos estão dentro do limite da resolução CONAMA 344/04, mas em alguns pontos amostrados os HPAs indicaram contaminação por elementos de origem petrogênica quando confrontados com os limites indicados nesta mesma resolução. Para evitar que os limites sejam excedidos, visto que alguns dos pontos amostrados estão muito próximos, ou extrapolando os limites indicados, faz-se necessário evitar a entrada de poluente nas cavas do parque em questão, devido ao grande risco de perder a qualidade destes corpos hídricos e prejudicar a sua função para a sociedade. A pesquisa permitiu identificar que o incremento da carga poluente é potencializado pelo escoamento superficial das chuvas, inferindo desta forma, a necessidade do controle da poluição difusa para a área do parque. Uma das possíveis soluções seria a implantação de sistemas de wetlands construídos, que podem funcionar como barreiras para a entrada de poluentes, principalmente nas cavas mais próximas às estruturas viárias pavimentadas. The water bodies have the characteristics affected by diffuse pollution through the drift of pollutants in the runoff from rain events or also by occasional evictions. This research was conducted in pools of the Water Park in Pinhais/PR and aimed to assess the quality of waters and sediments of water bodies and their correlation with diffuse pollution. The analyses from some physico-chemical, bacteriological and organic compounds PAHs and n-alkanes in 6 points, indicated possible changes in the quality of these water bodies. These pools will be designed for future use of secondary contact recreation such as fishing and water sports in the LAW 189/87 - Pinhais-PR, indicating that the water pools must answer these CONAMA Resolution 357/05, which sets limits for physical- chemical, biological and metal species that may cause damage to health and the environment. To support the discussion of the results for PAHs in sediment and metal species, is used the CONAMA Resolution 344/04. The limits given by CONAMA resolutions 357/05 and 344/04, are safety values. Based on these results, we identified the influence of rainfall in the concentrations of all variables. By comparing the results with CONAMA Resolution 357/05 for freshwater class 2, it might be noted that the parameters salinity, dissolved oxygen, turbidity, ammonia, nitrite, nitrate comply with the limits imposed by resolution, for the DBO Most points analyzed was within the limits, but in one of the exceeded limit. For Fecal coliform, most points are presented within the limits established by resolution. The variable sulfide does not meet CONAMA 357/05. Of the seven metals analyzed in water cadmium and iron are found above the ceiling for CONAMA 357/05. The metals copper, zinc, cadmium, nickel and lead in sediments are within the limit of CONAMA Resolution 344/04, but in some sampling sites indicated PAH contamination source elements petrogenic when confronted with the limits specified in this same resolution. To avoid the exceeding the limits, since some of the points are very close, or extrapolating the limits, it is necessary prevent the entry of polluting the pools of the park in question, due to the high risk of losing the quality of these bodies water and impair its function for society. The research identified that the increase in pollution load is powered by the runoff of rainfall, implying thus the need for control of diffuse pollution to the park area. One of the possible solutions would be the deployment of constructed wetlands, which can act as barriers to the entry of pollutants, mainly pools nearest paved road structures.

APA, Harvard, Vancouver, ISO, and other styles

Farthing, Tessa. "Impact of a Forested State Park on Nutrient Concentrations in an Agriculturally Dominated Watershed in Southwest Ohio." Miami University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=miami1626999681372348.

Full text

APA, Harvard, Vancouver, ISO, and other styles

McClure, Clara. "Long-Term Recovery of South Indian Creek Following Interstate Construction." Digital Commons @ East Tennessee State University, 2013. https://dc.etsu.edu/etd/2296.

Full text

Abstract:

The expansion of Interstate 26 from Erwin, TN to the North Carolina border was a project that potentially adversely impacted South Indian Creek because of the steep landscapes and potential for erosion. Several studies have shown the short-term, negative effects of road construction on the water quality of nearby water bodies. Non-point source pollution is the major source of water pollution in the United States. The primary objective of this research is to evaluate the long-term effects of the construction of Interstate 26 on South Indian Creek to see if there has been any ecological recovery. The Environmental Health Sciences Laboratory of East Tennessee State University was contracted by the Tennessee Department of Transportation to collect data from before construction (1991-1992), during construction (1993-1994), and postconstruction (1995-1996). Comparison of microbial enzyme activities and other parameters to present-day (2012-2013) water quality conditions indicate that South Indian Creek has not fully recovered from the effects of the construction of the interstate.

APA, Harvard, Vancouver, ISO, and other styles

Baltokoski, Valmir. "Modelo SWAT2005 aplicado às sub-bacias dos rios Conrado e Pinheiro Pato Branco-PR." Universidade Estadual do Oeste do Parana, 2008. http://tede.unioeste.br:8080/tede/handle/tede/297.

Full text

Abstract:

Made available in DSpace on 2017-05-12T14:47:51Z (GMT). No. of bitstreams: 1 Valmir Baltokoski.pdf: 2787750 bytes, checksum: fe61cb2f7c894d46e777852e6fec1e06 (MD5) Previous issue date: 2008-06-30 Hydrological models developing that may to predict the nonpoint source pollution and the land use and occupation impacts on water quality has been a powerful tool at agricultural systems study. Within this context, the objective of the present research work was to evaluate the SWAT 2005 (Soil and Water Assessment Tool) applicability to simulate surface runoff, sediments yield and total phosphorous flow mass. The research was developed in two contiguous watersheds, from Conrado and Pinheiro rivers, on the Pato Branco River basin, from Pato Branco and Mariopolis counties, Parana State. Climatological data relative to period 1979/2006 and observed data of flow rate, sediments yeld and total phosphorous concentration relative to 2004/2005 years, taken at two monitoring locations, were used. The model requires input data in spatial format concerning to land use and soils data, associated to a digital elevation model (DEM). It was used the AvSWAT_X interface with ArcView 3.3® and its extension Spatial Analyst 2.0®, for input and manipulation data. Monthly and yearly averages of flow rate, sediments yeld and total phosphorous mass flow were compared to the observed values, being this proceeding used in the model calibration and evaluation. The Nash-Sutcliffe Coefficient (COE) and the Sum of Deviations of the Simulated Data (Dv) were used to evaluate the modeling efficiency. The results have proved to be satisfactory for the several modelings. O desenvolvimento de modelos hidrológicos capazes de predizer o impacto das fontes difusas de poluição e do uso e ocupação do solo na qualidade das águas, superficiais e subterrâneas, tem sido de grande auxílio no estudo de agroecossistemas agrícolas. Com esse objetivo, foi utilizado o modelo Soil and Water Assessment Tool (SWAT 2005), para avaliar sua aplicabilidade na previsão de escoamento superficial, na produção de sedimentos e no fluxo de massa do fósforo total, utilizando técnicas de análise de sensibilidade e calibração. O estudo foi realizado em duas microbacias hidrográficas contíguas, dos rios Conrado e Pinheiro, afluentes do Rio Pato Branco, localizadas nos municípios de Pato Branco e Mariópolis, no Estado do Paraná. Foram utilizados dados climatológicos do período de 1979/2006 e dados observados de vazão, sedimentos e concentração de fósforo total dos anos 2004/2005 de duas estações de monitoramento instaladas na área de estudo. O modelo requer dados espacializados de usos e tipos de solos, associados com banco de dados e um Modelo Digital de Elevação. Utilizou-se a interface AvSWAT_X, com o ArcView 3.3® e a extensão Spatial Analyst 2.0®, para entrada e manipulação dos dados no modelo. As médias anuais e mensais das simulações de vazão, sedimentos e fósforo total, foram comparadas com os dados observados, procedimento que serviu para calibrar o modelo e avaliar seu desempenho. Tanto o coeficiente de eficiência de Nash-Sutcliffe (COE) como a soma dos desvios dos dados simulados em relação aos dados observados (Dv) foram utilizados para avaliar a eficiência do modelo. Os resultados mostraram-se satisfatórios para as várias modelagens realizadas.

APA, Harvard, Vancouver, ISO, and other styles

Dissart, Jean-Christophe. "The economics of erosion and sustainable practices : the case of the Saint-Esprit watershed." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0006/MQ44158.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Wei, Wang-Chia, and 王佳偉. "Effects of BMPs on Reducing Nonpoint Source Pollution and Improving Water Quality in Feitsui Reservoir." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/39699q.

Full text

Abstract:

碩士 國立臺北科技大學 土木與防災研究所 102 The Feitsui reservoir is the drinking water source for Taipei metropolis, and the nonpoint source pollution has been considered as an important issue. The Structural BMP is one of the best management practice (BMP) and is used in Feitsui reservoir management. In this study, we investigated the existing structural BMPs in Feitsui reservoir, and also integrated geographic information systems (GIS)and Stormwater Management Model (SWMM) to planning and assess the effects of buffer strips and the existing structural BMPs which in the condition of operating stably in Feitsui reservoir. The major water quality items contain suspended solids (SS), total phosphorus (TP) and biochemical oxygen demand (BOD). The results show that 50 m width of the buffer strips around the reservoir can reduce 80% of SS, 50% of TP, and 70% of COD for the subwatersheds with buffer strips. For the entire watershed, the 50m buffer strips mitigate up to 5% of pollutants. In addition, Vollenweider model is utilized to assess water quality in the reservoir and the results show that 19-22% of pollution reduction rate is required to achieve the goal of 10μg/L of TP. The 50m width of buffer strip and existing structural BMPs in the best condition of operating stably can contributed 1/3-1/4 reduction loads, which is 800 kgTP/yr. More BMPs in addition to BMP are necessary in the Feitsui reservoir watershed management.

APA, Harvard, Vancouver, ISO, and other styles

Wa, Shin-Ho, and 魏信和. "The Development and Application of Water Quality for River Basin -- The Study of Nonpoint Source Pollution Impact on River." Thesis, 1994. http://ndltd.ncl.edu.tw/handle/99059777940856895835.

Full text

Abstract:

碩士 國立中央大學 環境工程研究所 82 The main purpose of this study is to develop a water quality simulation model of river in order to aid the decision maker in water quality simulation of strategies planning of water pollution control. Moreover, this study also identify various water quality impact of point and nonpoint sources on river by the use of the water quality simulation model. The pollution sources considered includes point and nonpoint sources in the water quality simulation model. The component of river basin system considered includes branches, tributaries, tidal and non- tidal areas. The river system is assumed to be an one dimensional steady state system. The water quality parameters are simulated includes DO, BOD, T-N, and T-P with an assumption of first order decay of BOD,T-N and T-P. What are to be discussed in the case study of Chung-Gung River results have shown that : (1)it is required to consider nonpoint sources in the planning of water quality control strategy; (2)the loading of point source is fixed, the water quality impact will be added when the non-point sources discharge into the river. The water quality impact will become larger when the loading is larger; (3)the loading of point source is more larger then the water quality impact of varies loadings of nonpoint sources is vary small. But the water quality impact of nonpoint sources will be vary large when the loading of point source is small. So that the control of nonpoint sources is becoming a major challenge to water quality manager when the most point source pollution have been controlled; (4)in general, the water quality impact of distributed discharges will be reduced, nonpoint sources almost get into the river with distributed discharge. However, this study consider the nonpoint sources as most sever, so that the real water quality of river seems to be much better than the simulation results; (5)at various base flow, the water quality impact of nonpoint sources on river will be reduced when base flow become lager.

APA, Harvard, Vancouver, ISO, and other styles

"Modeling the impact of landuse changes on nonpoint source pollution loading in the Guanlan River Basin." 2001. http://library.cuhk.edu.hk/record=b5890668.

Full text

Abstract:

Hui Wing-chi. Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. Includes bibliographical references (leaves 127-141). Abstracts in English and Chinese. LIST OF TABLES --- p.xi LIST OF FIGURES --- p.xiii LIST OF ACRONYMS --- p.xvii Chapter CHAPTER ONE- --- INTRODUCTION Chapter 1.1 --- Background --- p.1 Chapter 1.2 --- Conceptual Framework and Study Objectives --- p.7 Chapter 1.3 --- Scope of the Research and Study Area --- p.10 Chapter 1.3.1 --- Location and Climate --- p.10 Chapter 1.3.2 --- Geology --- p.12 Chapter 1.3.3 --- Landuse Characteristics and Status of Water Quality --- p.13 Chapter 1.4 --- Significance of Study --- p.14 Chapter 1.5 --- Organization of Thesis --- p.16 Chapter CHAPTER TWO - --- LITERATURE REVIEW Chapter 2.1 --- Landuse Alteration --- p.17 Chapter 2.1.1 --- Urbanization and Landuse Changes --- p.17 Chapter 2.1.2 --- Detecting Landuse Changes in Urbanizing Region --- p.19 Chapter 2.2 --- Impact of Landuse Alteration on Water Quality --- p.21 Chapter 2.2.1 --- Point and Nonpoint Sources of Water Pollution --- p.22 Chapter 2.2.2 --- Nonpoint Source Pollution as a Worldwide Environmental Problem --- p.23 Chapter 2.2.3 --- Methods of Assessing Nonpoint Source Pollution --- p.24 Chapter 2.2.4 --- GIS-based Modeling of Nonpoint Source Pollution --- p.26 Chapter 2.2.5 --- Application of Remote Sensing on Water Quality Study --- p.27 Chapter 2.3 --- Landuse Changes and Their Water Quality Impacts in the Pearl River Delta --- p.28 Chapter 2.3.1 --- Economic Reform and Urbanization --- p.29 Chapter 2.3.2 --- Urban Redevelopment --- p.31 Chapter 2.3.3 --- Rural Industrialization --- p.33 Chapter 2.3.4 --- Water Pollution --- p.34 Chapter CHAPTER THREE - --- METHODOLOGY Chapter 3.1 --- Introduction --- p.36 Chapter 3.2 --- Computation of Areal Nonpoint Source Pollution Loading --- p.38 Chapter 3.2.1 --- Assumptions --- p.38 Chapter 3.2.2 --- Soil Conservation Service (SCS) Curve Number Method --- p.39 Chapter 3.2.3 --- Generation of Nonpoint Source Pollutants --- p.42 Chapter 3.2.4 --- Model Operation --- p.43 Chapter 3.3 --- Instream Water Quality Modeling --- p.45 Chapter 3.3.1 --- Description ofWASP5 --- p.46 Chapter 3.3.2 --- Hydraulic Parameters --- p.47 Chapter 3.3.3 --- Model Constants --- p.48 Chapter 3.4 --- Description of Model Input Data --- p.49 Chapter 3.4.1 --- Watershed Delineation --- p.49 Chapter 3.4.2 --- Soil Data --- p.51 Chapter 3.4.3 --- Rainfall Data --- p.52 Chapter 3.4.4 --- Detection Landuse Changes --- p.53 Chapter 3.4.4.1 --- Image Preprocessing --- p.54 Chapter 3.4.4.2 --- Classification and Post-classification Analysis --- p.57 Chapter 3.4.4.3 --- Assessment of Accuracy --- p.60 Chapter 3.5 --- Scenario Modeling --- p.61 Chapter CHAPTER FOUR - --- INTERFACING ARCVIE W GIS WITH WATER QUALITY MODEL Chapter 4.1 --- Watershed Parameter Generator --- p.64 Chapter 4.1.1 --- Topographic Analysis and Stream Network Definition --- p.65 Chapter 4.1.2 --- Vectorization of Basin Geometries --- p.68 Chapter 4.1.3 --- Computation of Basin Geometric Characteristics --- p.69 Chapter 4.2 --- Nonpoint Source Pollution Loading Generator --- p.69 Chapter 4.3 --- Instream Water Quality Calculator --- p.74 Chapter CHAPTER FIVE- --- LANDUSE AND LAND COVER CHANGES ANALYSIS Chapter 5.1 --- Framework for Analysis --- p.78 Chapter 5.2 --- Landuse Changes During the Study Period --- p.82 Chapter 5.2.1 --- Areal Landuse Changes --- p.82 Chapter 5.2.2 --- Inter-category Landuse Changes --- p.86 Chapter 5.2.2.1 --- Rural-to-urban Changes --- p.86 Chapter 5.2.2.2 --- Rural-to-rural Changes --- p.87 Chapter 5.2.3 --- Error matrix --- p.88 Chapter 5.3 --- Spatial Pattern of Landuse and Land cover --- p.91 Chapter 5.3.1 --- Urban Land --- p.92 Chapter 5.3.2 --- Rural Areas --- p.94 Chapter 5.4 --- Scenario Building --- p.96 Chapter 5.5 --- Limitation of Landuse Classification based on Satellite Image Interpretation --- p.96 Chapter 5.6 --- Summary --- p.98 Chapter CHAPTER SIX - --- IMPACTS OF LANDUSE CHANGES ON NONPOINT SOURCE POLLUTION LOADING AND WATER QUALITY Chapter 6.1 --- Impact of Landuse Changes on NPS Loading --- p.100 Chapter 6.1.1 --- Identification of Curve Number --- p.100 Chapter 6.1.2 --- Runoff and Areal Nonpoint Source Pollution Loadings --- p.101 Chapter 6.1.3 --- Sensitivity of NPS Pollution Loading to Landuse Changes --- p.107 Chapter 6.2 --- Instream Water Quality Analysis --- p.110 Chapter 6.2.1 --- Downstream Variation of Water Quality --- p.111 Chapter 6.2.2 --- Comparison with NWQC II --- p.114 Chapter 6.3 --- Strategic Landuse Management --- p.117 Chapter 6.4 --- Limitation of the Study --- p.118 Chapter CHAPTER SEVEN - --- CONCLUSION Chapter 7.1 --- Summary of Findings --- p.122 Chapter 7.1.1 --- Landuse and Land Cover Changes --- p.122 Chapter 7.1.2 --- GIS-based Water Quality Modeling --- p.123 Chapter 7.1.3 --- Pollution Loading and Instream Water Quality --- p.124 Chapter 7.2 --- Future Study --- p.125 REFERENCES --- p.127

APA, Harvard, Vancouver, ISO, and other styles

Hart, Heather Melanie. "Effect of land use on total suspended solids and turbidity in the Little River Watershed, Blount County, Tennessee." 2006. http://etd.utk.edu/2006/HartHeather.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!