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Effectiveness of State Developed and Implemented Forestry Best Management Practices in the United StatesCristan, Richard 28 June 2016 (has links)
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.
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Effects of forest harvesting best management practices on surface water quality in the Virginia coastal plainFrazee, Joseph W. 04 September 2008 (has links)
Three watersheds located in Westmoreland County, Virginia were monitored to evaluate effectiveness of forestry best management practices (BMPs) for minimizing hydrologic and water quality impacts associated with timber harvesting. One watershed was clear-cut without implementation of BMPs, one watershed was clear-cut with the implementation of BMPs and the third watershed was left undisturbed as a control. The 27 months of pre-harvest monitoring data and 17 months of post-harvest monitoring data were compared using the paired watershed regression analysis and the minimum detectable change (MDC) statistic.
Analysis of the hydrologic data showed that peak discharge rates were not impacted by harvesting, regardless of whether BMPs were implemented. Harvesting with or without the implementation of BMPs resulted in no statistically significant change in stormflow volume.
BMP implementation was found to be effective in minimizing harvesting impacts on stormflow total suspended solids (TSS), ammonia, total Kjeldahl nitrogen (TKN), total nitrogen (TN), sediment-bound nitrogen and total phosphorous (TP) concentrations and total flow TSS and TP concentrations. BMP implementation was also effective in minimizing harvesting impacts on stormflow TSS, TKN, sediment-bound nitrogen, TP and sediment-bound phosphorous loadings and total ammonia loading. The BMPs were not effective in reducing nitrate concentrations and loadings. The BROOK90 forest hydrology model was used to predict the site hydrology. Model predictions compared favorably with streamflow measurements from watersheds QN3 and QN4 until the time of harvest, but did not predict streamflows as accurately for the control watershed, QN5. / Master of Science
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Phosphorus Losses from Simulated Dairy Mangement Intensive Grazing Forage SystemTeany, Laura Ellen 07 January 2005 (has links)
Dairy producers across the country are evaluating the effectiveness of management intensive grazing (MIG) systems as a means of reducing the economic pressures of confinement feeding and manure handling. Systems using MIG have been promoted as an environmentally safer way of managing nutrient balance on Center. However, little research has been conducted to evaluate how these systems affect phosphorus (P) loss from the Center through runoff and forage removal. The goal of this study was to investigate the effects of forage type and manure density on P levels in runoff from release plots that simulated a MIG dairy system.
Two forage treatments were planted on runoff release plots and applied with three manure density treatments and four replications of each combination for a total of 24 plots. Orchardgrass (Dactylis glomerata) and a broad-leafed forage treatment consisting of buckhorn plantain (Plantago lanceolata), red clover (Trifolium pratense), and alfalfa (Medicago sativa) were planted on the runoff release plots in early spring. Manure densities with no manure (control), a density simulating a low stocking density (low), and a density simulating high stocking density (high) were applied to plots during grazing simulations. Six rainfall simulations were conducted over the season simulating grazing conditions when forage was removed and re-growth conditions when forage had reached its target re-growth height before re-grazing occurred. Thirty minutes of runoff was collected from the runoff release plots to determine first flush phosphorus losses from the various treatments.
Mass losses of total phosphorus (TP) for manure treatments in series 1 were significant due to plot installation disturbance. No significant effect for ortho-phosphorus (ortho-P), particulate phosphorus (PP) or TP concentration or mass losses were observed for other simulation series. Significantly higher mass losses were observed in series 1 for both forage treatments, again due to installation disturbance. Seasonal mass losses for TP were significantly lower for the orchardgrass treatment.
Forage mass removal over the season increased as the stands established. Orchardgrass treatments appeared to control P losses earlier in the season, while broadleaf treatments observed a steady increase in ortho-P losses up to series 5. Both mass and concentration losses of TP were controlled earlier in the season by orchardgrass, while PP showed no significant mass or concentration loss effects. / Master of Science
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Nutrient Movement in Streamside Management Zones and Piedmont Streams Following Forest FertilizationSecoges, Joseph Michael 06 July 2009 (has links)
Many states' 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
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Comparative modelling of phosphorous production in rural catchmentsMatji, Maselaganye Petrus 12 1900 (has links)
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.
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A descriptive analysis of the waterways in Coos Bay Oregon on the basis of general, ruminant and human Bacteroides-Prevotella 16S rDNA markersJones, Thomas E. 12 February 2003 (has links)
We explain a new method of detecting non point source fecal contamination
using a PCR based method called Touchdown Polymerase Chain Reaction (TD-PCR).
Using genetic markers particular to general, ruminant and human Bacteroides-
Prevotella genes, we identified presence in both fresh and salt water environments.
Water samples from four sites were collected at approximate 2-week intervals for a
year. Samples were analyzed for total coliforms, fecal coliforms, E. coli, and the
presence of general, ruminant and human Bacteroides-Prevotella markers. We
compared the odds of recovering each PCR marker between sites. We investigated the
relationship between rainfall and recovery of PCR markers. Finally, we compared the
sensitivity of the PCR methods to standard public health methods. / Graduation date: 2003
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Optimal allocation of stormwater pollution control technologies in a watershedChen, Wei-Bin, January 2006 (has links)
Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 250-274).
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A watershed management decision support system (WAMADSS) : economic and environmental impacts of land use activities for reducing nonpoint source pollution /Fulcher, Christopher L. January 1996 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1996. / Typescript. Vita. Includes bibliographical references (leaves 262-273). Also available on the Internet.
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Effect of land use on total suspended solids and turbidity in the Little River Watershed, Blount County, TennesseeHart, Heather Melanie, January 2006 (has links) (PDF)
Thesis (M.S.) -- University of Tennessee, Knoxville, 2006. / Title from title page screen (viewed on Sept. 19, 2006). Thesis advisor: Joanne Logan. Vita. Includes bibliographical references.
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Development and Evaluation of Infilling Methods for Missing Hydrologic and Chemical Watershed Monitoring DataJohnston, Carey Andrew 30 September 1999 (has links)
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
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