WorldCat Identities

Matthews, Robin A. 1952-

Works: 56 works in 121 publications in 1 language and 2,088 library holdings
Genres: Academic theses  Field guides 
Roles: Author, Editor, Contributor
Classifications: TD146, 628
Publication Timeline
Most widely held works by Robin A Matthews
Environmental engineering by Ruth F Weiner( )

25 editions published between 2003 and 2011 in English and held by 1,976 WorldCat member libraries worldwide

This book provides a comprehensive introduction to air, water, noise, and radioactive materials pollution and its control. Legal and regulatory principles and risk analysis are included in addition to engineering principles. The text presents the engineering principles governing the generation and control of air and water pollutants, solid and hazardous waste, and noise. Water quality and drinking water treatment are discussed, as well as the elements of risk analysis. Radioactive waste generation and treatment in relation to the nuclear fuel cycle, are discussed. The health and environmental effects of all these pollutants are discussed. An introduction to the Federal laws and regulations governing pollution is included. - This text embraces the latest thinking in environmental engineering - Includes updates in regulation and current pollution abatement technologies
Phellinus weirii root rot of Douglas fir in the Sehome hill Arboretum : distribution, impact and management options by William G Cantrell( )

2 editions published in 1990 in English and held by 3 WorldCat member libraries worldwide

This study examines the cause, distribution and impact of a forest pathogen within the 71 forested hectares of the Sehome Hill Arboretum in urban Bellingham, Washington. The causal agent was determined by the identification of cultures from decaying wood in douglas fir (Pseudotsuga menziesii (Mirbel) Franco) to be the root rotting basidiomycete Phellinus weirii (Muir.) Gilb. A ground survey of aboveground symptoms was used to detect 31 infection centers covering 6.64 hectares (9.2% of the Arboretum) of symptomatic trees. Infra-red aerial photography was used to determine canopy cover for deciduous and evergreen species. A forest canopy survey was conducted to determine canopy dominance in each of 22 forested regions of the Arboretum. Basal area at breast height was used to establish dominance. Tree density and size-class distributions were used to predict future dominance in the presence of continuing Phellinus root rot infection. Seven management approaches were discussed
Algae in northwest Washington lakes by Robin A Matthews( Book )

in English and held by 3 WorldCat member libraries worldwide

An exploratory statistical analysis of the ground water in the Abbotsford-Sumas aquifer by Sharon Gelinas( )

2 editions published in 2000 in English and held by 3 WorldCat member libraries worldwide

The Abbotsford-Sumas aquifer is a primarily unconfined aquifer, located in Whatcom County, WA, with a history of nitrate contamination. Whatcom County is a large producer of raspberries and contains numerous dairy farms. Both of these agricultural practices involve large quantities of nitrates being produced or used for fertilization. A two-year ground water monitoring program was conducted in 1997 and 1998 by Western Washington University in order to determine the spatial and temporal extent of the nitrate contamination. Possible trends in nitrate concentrations may be associated with ground water movement, chemical and biological nitrate reduction processes, seasonality and land use. Exploratory univariate, bivariate and multivariate statistical analyses were utilized to determine the dominant processes affecting nitrate concentrations in the study area. Nitrate concentrations in shallow wells were associated with local agricultural practices and nitrate concentrations in deeper wells were associated with agricultural practices occurring up-gradient in Canada. Differentiating land use based on nitrate concentrations was determined to be inconclusive. Denitrification was occurring in over half of the wells in the study area. Several types of nitrate concentration trends were observed: higher nitrate concentrations in the fall and winter due to nitrification in the spring and summer; higher nitrate concentrations in the spring and summer due to nitrogen inputs; a steady increase or decrease in nitrate concentrations; no detectable nitrate concentration. Multivariate statistical analyses confirmed that there was not one dominant process affecting nitrate concentrations in the Abbotsford-Sumas study area; therefore, nitrate concentration trends are due to a combination of processes
Hydrogeochemical interactions in a subalpine watershed, Mount Baker National Recreation Area, Washington by JoAnn Michele Holloway( )

2 editions published in 1993 in English and held by 3 WorldCat member libraries worldwide

The Upper Bagley watershed was monitored from April to November, 1992. The watershed is described as a series of chemically distinct subsystems: 1) the snowpack, 2) soil solutions, and 3) surface water. The hydrogeochemical interactions between these subsystems were investigated in the Upper Bagley watershed. Chemical analyses of these fluids were used to identify how soil solutions vary from water derived from the snowpack and what impact soil solutions have on surface-water chemistry. Water-ice interactions alter the snowpack chemistry, enriching the melt in calcium, magnesium, sodium, chloride, and sulfate that accumulate at the surface of ice crystals. The melt from the Upper Bagley watershed is enriched in calcium and sodium by a factor of three and in magnesium by a factor of six relative to snow concentrations. Chloride and sulfate concentrations are up to four times greater in the melt fraction. Nitrate does not become concentrated in the melt fraction since the equilibrium of nitrate in the snowpack is controlled in part by denitrification. Soils in the Upper Bagley watershed are Entisols, or primitive soils. Two soils types were defined on the basis of clay content and the ability of the soil to support vegetation. Soil I, a clay loam that originates from glacial till and volcanic ash, is composed of montmorillonite, inorganic colloids, and organic acids. This soil supports vegetation dominated by heather and sedge. Soil II, a gravelly sand loam derived from andesite with sparse vegetation, is primarily andesine and inorganic colloids. Pore fluids from these soils are chemically distinct. Pore fluids from Soil I (Pore Fluid I) have greater ion concentrations that those from Soil II (Pore Fluid II). Pore Fluid I is dominated by calcium and sulfate and is more acidic than Pore Fluid II, which is dominated by sodium. The chemical composition of surface water in the Upper Bagley watershed reflects the mixing of fluids derived from snow and soil solutions. End-Member Mixing Analysis suggests that solutions from the inlet, outlet, and lake are a mixing product between four end-members: 1) the relatively dilute snow and melt, 2) surface water that has leached cations from vegetation, 3) Pore Fluid I, and 4) Pore Fluid ll. When plotted against chloride concentrations, calcium, magnesium, and sulfate provide evidence for the mixing of fluids in the Upper Bagley watershed. Processes other than simple mixing also influence the chemistry of the Upper Bagley watershed. Nitrate and alkalinity concentrations for the fluids do not provide evidence for interaction between fluids. The equilibria of these ions are more strongly affected by biological transformations (nitrate) and gas exchange with the atmosphere (alkalinity). Normalized mixing analysis was used to indicate individual sample clusters that do not demonstrate simple mixing. Ions were normalized for chloride and plotted against each other. Plots of calcium, magnesium, and sulfate normalized to chloride are strongly linear because the equilibria of these ions are controlled in part by mixing. Correlation of the data clusters that diverge from the linear plot pattern with field conditions at the time of collection indicates that redox reactions and aerosol deposition also control the chemical equilibria of the watershed
Application of a nitrate fate and transport model to the Abbotsford-Sumas aquifer, Whatcom County, Washington by Margo A Burton( )

2 editions published in 2007 in English and held by 3 WorldCat member libraries worldwide

The Abbotsford-Sumas aquifer is a shallow, unconfined aquifer located in an agriculturally intensive area in northwestern Washington and southwestern British Columbia. Due to aquifer characteristics and surface land use, the Abbotsford-Sumas aquifer has had a history of nitrate contamination from non-point sources. As such, nutrient managers are interested in predictive tools to evaluate management strategies. I assessed the effectiveness of a GIS based nitrate fate and transport model developed specifically for the Abbotsford-Sumas aquifer by Almasri and Kaluarachchi (2004) as a predictive tool for nutrient management. This model couples four sub-models that collectively estimate nutrient loading, predict soil-nitrogen dynamics (NLEAP), calculate groundwater velocity (MODFLOW), and nitrate fate and transport in groundwater (MT3D). The model was used to validate measured nitrate concentrations in the aquifer, and to assess the impact of land use changes and irrigation on nitrate concentrations. Validating nitrate concentrations was difficult due to the model's design as a single layer aquifer. For those well sites with similar modeled and measured depths, the model was fairly effective at predicting nitrate concentration. Previous work has shown that nitrate is stratified in the Abbotsford-Sumas aquifer, but this fate and transport model estimates the same nitrate concentration for an entire water column. The model was sensitive to land use changes; however, the scale of the model is too coarse to capture local changes and seasonal variation. Changes in irrigation rate and concentration showed little change in resulting nitrate leaching. This lack of response is contrary to previous work, and indicates that the model underestimates irrigation's impact on groundwater nitrate concentrations
An investigation of denitrification events along Pangborn Creek in the Abbotsford-Sumas aquifer, Washington by Leslie B McKee( )

2 editions published in 2004 in English and held by 3 WorldCat member libraries worldwide

The Abbotsford-Sumas aquifer is a shallow, unconfined aquifer located in the agricultural regions of southwestern British Columbia and northwestern Washington and has a history of nitrate contamination. I monitored nitrate distributions in a study area bisected by a wide- scale peat deposit within a portion of the Whatcom County component of the aquifer to assess the current nitrate distribution, evaluate ground and surface water interactions in the peat, and determine the affect of peat on denitrification. The water quality dataset and statistical analyses showed that nitrate contamination was heavily concentrated upgradient of the peatlands. In general, shallow wells (<10 m below the median water>table) north of the peatlands had higher nitrate concentrations than deeper wells (>10 m below the median water table). Some upgradient wells showed low nitrate concentrations and data suggest they received denitrified ground water from unmapped peat deposits. Nitrogen isotope data ([lower case delta]15N on nitrate) indicated that nitrate sources included manure and inorganic commercial fertilizers. The contamination south of the peatlands was significantly lower than the contamination to the north and the median nitrate levels within the peatlands were near the detection limit. Nitrogen gas measurements and a combination of nitrogen ([lower case delta]15N on nitrate) and oxygen ([lower case delta]180 on water) isotopes confirmed that denitrification occurred in the peatlands and in much of the ground water south of the peatlands. In addition, the gas measurements suggested that iron, manganese, sulfate, and methane occurred throughout the peatlands and may have contributed to redox reductions. The implication of these findings is that a natural means for nitrate reduction exists in this region. Hydrostratigraphic data suggest that peat deposits occur throughout Whatcom County at various unmapped depths. Identifying these peat deposits and quantifying the upgradient ground water nitrate contributions may help facilitate nutrient management in the region
Characterization of particulate matter accumulated on Ramalina farinacea in the Seattle area using semi-automated electron microscopy by Tor G Guddal( )

2 editions published in 2018 in English and held by 2 WorldCat member libraries worldwide

Semi-automated scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDS) can be used to determine the size and composition of filtered particulate matter (PM). This information is valuable for determining the identity and contribution of overlapping air emissions. One limitation of this method is the cost of filtering PM at enough locations to give meaningful spatial data. To address this limitation, I developed an exploratory method to collect PM using Ramalina farinacea for semi-automated SEM analysis as a component of lichen biomonitoring studies. I applied this method as a proof of concept in the Seattle area to better understand trends in regional urban dust. To do this, bags of lichen were transplanted to 9 locations in the Duwamish Valley and adjacent uplands for 3 months between September and December, 2017. Some of these locations were arranged close to major industrial sources of airborne metals, which we hypothesized would contribute to the PM observed on the lichens alongside the regional background signature of particulate emissions. Upon collection, PM deposition on the lichen was characterized using SEM with EDS. A total of 18,581 particles were identified and analyzed using the PACLA for Oxford two-stage classifier. My findings suggest that R. farinacea are an effective tool for collecting PM and show the greatest proportion of anthropogenic-specific particles on lichens adjacent to Interstate 5. Furthermore, the spatial trends of PM between locations suggest that fugitive dust controls such as green walls and green spaces may be more effective than point source controls at further reducing exposure to harmful dust in the Seattle area
The effects of decomposing macrophytes, aeration, and temperature on water quality measurements in microcosms with sediment and water from Lake Whatcom, Washington by Kirsten M Lee( )

1 edition published in 1996 in English and held by 2 WorldCat member libraries worldwide

Lake Whatcom sediment and water were used to study decomposition processes through the effects of temperature, aeration, and decaying macrophytes on water quality and microbial respiration using laboratory microcosms during a 43-day experiment. Thirty-two, 900 mL glass jars containing sediment and water from Lake Whatcom were placed randomly into eight treatment groups. Treatments were defined by temperature, presence or absence of aeration, and presence or absence of decaying macrophytes. The microcosms were sampled immediately prior to initiation of treatment, one and three days after treatment and then weekly over a six-week period. Water samples were collected 3 cm above the sediment surface through silicon rubber ports in the top of the microcosms using syringes and 20 gauge needles. Micro-volume analysis techniques were developed and employed to determine the concentrations of dissolved oxygen, ammonia, nitrogen, and phosphorus as well as to compare the rates of microbial respiration through INT reduction in each microcosm. The data were analyzed using parametric and nonparametric analyses of variance, graphic, and cluster analysis techniques. Of the three factors, the presence of decaying macrophytes had the greatest impact on water quality. Nutrient concentrations and microbial respiration were higher in the microcosms containing plant material. Aeration also affected water quality by lowering nutrient concentrations and increasing dissolved oxygen levels within the microcosms. Temperature did not significantly affect dissolved nutrient concentration, but did influence respiratory activity and percent weight loss of the macrophytes in the leaf packs
Effects of heavy metals on benthic macroinvertebrates in the Cordillera Blanca, Peru by George L Burgess( Book )

2 editions published in 2015 in English and held by 2 WorldCat member libraries worldwide

Glacial retreat as a result of global climate change is causing ongoing alterations in the hydrogeochemistry of streams in the glacial foreland of the Cordillera Blanca mountain range in Ancash, Peru. Changes in water chemistry include increased concentrations of toxic metals and decreased pH, which have the potential to affect the structure of benthic macroinvertebrate communities in impacted streams. This study measured physical-chemical water quality parameters, metal concentrations, and macroinvertebrate abundances at 29 sample reaches throughout seven valleys located in Huascaran National Park. The relationships of invertebrate abundances and metrics of community structure to water quality parameters, including metal concentrations, were analyzed by non-parametric correlation. Several sensitive local taxa were identified, including the Baetidae, Heptageniidae, Helodidae, and Tabanidae families, as well as the Oligochaeta. In addition, a regional source analysis was conducted for toxic metals, which found six of seven consistently detected metals share a common source. Finally, an analysis of the cumulative criterion unit (CCU) was performed; CCU, an approach to metal mixture toxicity, can be calculated either on the basis of total or dissolved metals. Previous studies in the region used total metal concentrations. Invertebrate abundances and metrics correlated about as well or slightly better, in general, with CCU computed on the basis of dissolved metals as they did with CCU computed with total metals
Identifying the sources of Escherichia coli in Lake Whatcom, Bellingham, Washington using amplified fragment length polymorphism (AFLP) analysis by Lesli Higginson( )

1 edition published in 2004 in English and held by 2 WorldCat member libraries worldwide

Amplified fragment length polymorphism (AFLP) analysis was applied to a bacterial source tracking study at Lake Whatcom, Bellingham, Washington to determine if humans, dogs, Canada geese, or all three animal sources were contributing to the Escherichia coli contamination in the lake. E. coli were isolated from Lake Whatcom surface waters, sediment samples, and the three potential animal sources. Genomic DNA extracted from the E. coli isolates was analyzed using the AFLP technique. Fragments produced by a restriction digest using two restriction endonucleases were ligated to double stranded-adapter molecules that served as primer binding sites for two subsequent polymerase chain reactions. Three AFLP data sets were generated, one with primer pair EcoRI-A/MseI-C, the second with primer pair EcoRI-A/MseI-G, and the third, a composite data set created by combining the results from the two primer sets. Principal components analysis and cluster analysis of AFLP data showed three groupings of the E. coli isolates. E. coli isolates from goose feces had the highest number of correctly classified isolates, up to 84%. Approximately half of the isolates from human feces and 19-35% of the isolates from dog feces classified correctly. The analysis of the composite data set showed that Canada geese were the major source of fecal contamination at the Bloedel Donovan swim area on Lake Whatcom
Predicting risk to estuary water quality and patterns of benthic environmental DNA in Queensland, Australia using Bayesian networks by Scarlett E Graham( )

2 editions published in 2016 in English and held by 2 WorldCat member libraries worldwide

Predictive modeling can inform natural resource management by demonstrating stressor-response pathways and quantifying the effects on selected endpoints. This study develops a risk assessment model using the Bayesian network-relative risk model (BN-RRM) approach, and, for the first time, incorporates eukaryote environmental DNA data as a measure of benthic community structure into an ecological risk assessment context. Environmental DNA sampling is a relatively new technique for biodiversity measurements that involves extracting DNA from environmental samples, sequencing a region of the 18s rDNA gene, and matching the sequences to organisms. Using a network of probability distributions, the BN-RRM model predicts risk to water quality objectives and also the richness of benthic taxa in the Noosa, Pine, and Logan Estuaries in South East Queensland (SEQ), Australia. The model is more accurate at predicting Dissolved Oxygen than it is the Chlorophyll-a water quality endpoint, and it predicts photosynthesizing benthos more accurately than heterotrophs. Results of BN-RRM modeling indicate that the water quality and benthic assemblages of the Noosa are relatively homogenous across all sub risk regions, and that the Noosa has a high probability (73 - 92% probability) of achieving water quality objectives, which indicates low relative risk. On the other hand, the Middle Logan, Middle Pine, and Lower Pine regions are much less likely to meet objectives (15 - 55% probability), indicating a relatively high risk to water quality in those regions. The benthic community richness patterns associated with low relative risk in the Noosa are high Diatom relative richness and low Green Algae richness. The only benthic pattern consistently associated with high relative risk to water quality is the high Fungi richness state. The BN-RRM predicts current conditions in SEQ based on available monitoring data, and provides a basis for future predictions and adaptive management at the direction of resource managers. As new data are made available or more questions are asked, this BN-RRM model can be updated and improved
Phytoplankton composition and temporal variation among the three basins of Lake Whatcom, Washington by William James Ehinger( )

1 edition published in 1988 in English and held by 2 WorldCat member libraries worldwide

The phytoplankton populations were studied over a one year period in the three basins of Lake Whatcom, a warm, monomictic, chain lake in northwestern Washington. The water quality in all three basins was similar while the lake was unstratified. Following stratification, basins 1 and 2 developed anoxic hypolimnia, with subsequent release of ammonia and phosphorus from the sediments, while basin 3 had relatively high concentrations of oxygen throughout the water column. During the summer the flow out of basin 1 was greatly reduced, while the flow in basin 2 was maintained through the municipal water withdrawal by the City of Bellingham, WA. Water quality conditions developed in basin 1 that favored the growth of the blue-green alga Coelosphaerium naegelianum (low concentrations of combined, inorganic nitrogen and low N:P ratios). Coelosphaerium biovolume in basin 2 was approximately 3% that of basin 1 while basin 3 did not develop a significant blue-green algal population. Although the Coelosphaerium blooms were correlated with the internal release of ammonia and phosphorus during stratification, basin 2 did not develop Coelosphaerium blooms similar to basin 1 because of the greater inflow of water from basin 3, which contained comparatively higher concentrations of nitrate, and because of the increased flushing rate in basin 2 due to the municipal water withdrawal
Macroinvertebrate bioassessment of five Lake Whatcom, WA, tributaries by Dwight J Osmon( )

1 edition published in 2002 in English and held by 2 WorldCat member libraries worldwide

Five streams (Anderson Creek, Austin Creek, Brannian Creek, Olsen Creek, and Smith Creek) located in the eastern portion of the Lake Whatcom, WA (USA), watershed were selected for a macroinvertebrate bioassessment study. Water quality samples were collected at all sites in July 2001, September-October 2001, and February 2002 to characterize summer, fall, and winter conditions. Results of the water quality portion of this study indicated no statistically significant differences among research sites for nutrients, temperature, dissolved oxygen, pH, conductivity, turbidity, or alkalinity. There were slight differences among sites for pH and conductivity with respect to the range of values, but the differences were not statistically significant due to the low number of replicates. Substrate composition, riparian habitat, and aspects of channel morphology were evaluated at each study stream in September-October 2001. There were no statistical differences among sites for any substrate categories, riparian habitat or channel morphology characteristics. Substrate was composed mainly of cobble, coarse gravel, and fine gravel. The riparian habitat showed slight differences in canopy cover ranges, but due to the low number of replicates at each site, the differences were not statistically significant. Generally, the sites fell into three categories: closed canopy (Brannian Creek); deciduous canopy (Anderson, Austin, and Olsen Creeks); and open canopy (Smith Creek). Benthic macroinvertebrate samples were collected at all sites in September-October 2001 and evaluated using multiple measures of diversity and community integrity. Sites were compared using unsealed biometric criteria (raw scores) such as the number of Ephemeroptera, Plecoptera, and Trichoptera (EPT) taxa, the percentage of Cinygma, and the ratio of EPT individuals to total individuals. The Benthic Index of Biotic Integrity (B-IBI) was used to compare the Lake Whatcom tributaries with other Puget Lowlands streams. The B-IBI's for macroinvertebrates in the Lake Whatcom watershed were relatively high compared to other streams in the Puget Lowlands indicating clean water and good macroinvertebrate habitat in the Lake Whatcom watershed. Austin Creek and Smith Creek macroinvertebrate data indicated these streams contained relatively large amounts of organic suspended solids that could contribute to the overall productivity of Lake Whatcom. Smith Creek also showed indications of temperature stress. Anderson Creek showed signs of low habitat complexity and sedimentation. Bootstrap sampling was used to evaluate the performance of the B-IBI and other biometric criteria. The bootstrap sampling results indicated the B-IBI performed poorly at low counts (100-500 individuals). The variance among recounts remained high and the B-IBI did not reach a stable score until 1000 or more individuals were counted. The performance of the EPT individuals to total individuals ratio showed low variance and a stable mean value at counts of 100 individuals. The EPT individuals to total individuals ratio also ranked sites in the same order as the other biometric criteria
Predicting cyanobacteria blooms in 50 lakes of Northwest Washington by Chandra T Llewellyn( )

2 editions published in 2010 in English and held by 2 WorldCat member libraries worldwide

Eutrophication is one of the foremost problems affecting our freshwater resources. Excessive nutrient loading impacts freshwater lakes by altering ecosystem processes and degrading water quality, often resulting in human-induced eutrophication. Worldwide, cyanobacteria blooms occur in many anthropogenically eutrophic lakes. Such blooms are of increasing concern in the Pacific Northwest because they negatively affect lake system and function. A major concern is their unpredictable production of toxins, which can be deadly to animals, including humans. Therefore, an improved understanding of the incidence and persistence of cyanobacteria blooms is a critical aspect of protecting our water supply. The goal of this thesis was to attempt to create a predictive model based on simple water quality characteristics that would classify lakes according to bloom status using a multivariate statistical approach. Additional possible bloom contributors such as, light availability, landscape properties, N:P ratios or other interactive effects were not investigated in this study. During 2007-2009, 50 lakes in Northwest Washington were sampled to measure standard water quality (water chemistry) parameters as part of the Institute of Watershed Studies' (IWS) small lakes monitoring project. In addition, algal samples were collected during 2007-2009. The IWS study created a water quality baseline for many previously unmonitored lakes and revealed that a number of lakes experienced cyanobacteria blooms. Previous studies have used high phosphorus as an indicator of cyanobacteria blooms. I tested phosphorus, as well as chlorophyll, as possible indicators of cyanobacteria blooms. Based on hierarchical, Kmeans and non-metric clustering, the lakes sampled by IWS can be clustered into two groups based on differences in conductivity, alkalinity, total phosphorus and turbidity. However, chlorophyll and phosphorus concentrations did not predict lakes that were dominated by cyanobacteria blooms. High phosphorus levels were usually associated with high chlorophyll levels, but high chlorophyll levels were not always associated with cyanobacteria dominance. Using the water chemistry, data high phosphorus was a good indicator of algal blooms, but could not be used as an exclusive predictor of cyanobacteria blooms. Linear discriminants analysis was used to build a predictive model based on the 2007-2008 water quality data to try to classify the 2009 samples by cyanobacteria dominance. The model was unsuccessful (30% success rate) in predicting cyanobacteria blooms within the 2009 data. Despite the fact that algal blooms are fairly predictable using water chemistry data, this study highlights the complexity of predicting harmful cyanobacteria blooms in the Pacific Northwest
Population characteristics and habitat use by the recently introduced Asiatic clam (Corbicula fluminea) in Lake Whatcom, Washington by Jason A Buehler( )

2 editions published in 2017 in English and held by 2 WorldCat member libraries worldwide

The Asiatic Clam (Corbicula fluminea) was found in Lake Whatcom in 2011. This exotic clam is common throughout North America and is spread between watersheds by infested boats, fishing activities, as well as passively by waterfowl. Corbicula fluminea is a well documented invasive species that survives in many environments and exhibits an r-selected life history which can lead to potentially rapid population growth via a clonal reproductive ability typical among invasive bivalves and members of the family Corbiculidae. There are more reproductive strategies in Corbiculidae than any other freshwater bivalve. This rapid growth of a single organism and its associated consumption and excretions can lead to undesired changes in an aquatic ecosystem. Studies have shown a drop in species richness, alterations to algal communities and their availability to other organisms, and water quality changes associated with burrowing, shell accumulation, and clam decomposition. My research included an assessment of the growth of representative Lake Whatcom clam populations during 2012 and 2013 using shellfish surveying methods that have been applied to the marine intertidal environment. Surveying was based on multiple transects with randomly sampled 0.25-square meter quadrats. Three sites were identified that had populations of the clam and were accessible for surveys. These sites were Bloedel Donovan Park in the City of Bellingham, Lakewood, a facility run by Western Washington University, and a small park beach within the community of Sudden Valley. Surveys showed sample areas with 200 or more individual clams per square meter at all three sites. Studies state this density to be indicative of a self-sustaining population for C. fluminea. Some sites exhibited an increase in biomass and size from 2012 to 2013. All sites showed significant changes among some size classes that suggest growth. The sand and fine sediment substrate of the Sudden Valley site hosted significant density increases and biomass increases from 2012 to 2013. The harder rocky substrate of Lakewood hosted multiple size classes but did not show evidence of growth. Bloedel Donovan Park differed from the other sites in that it had a small size class in 2013 that was not present in 2012 suggesting a new generation of clams had reseeded the habitat. The overall environment within Lake Whatcom does not appear to be conducive to extended periods of reproduction based on the presence of distinct size classes. Distinct size classes are representative of specific reproductive windows during the year made available during the warmer months of summer. Density and biomass changed with depth within the nearshore shallows suggesting that the cooler deeper waters of the lake are not as suitable to the clam as the warmer, shallower areas within the littoral zone. Another explanation is less phytoplankton availability due to light limitations imposed by depth. Corbicula fluminea appears to be reproducing to varying degrees at all three sites in this study, and it will likely continue to spread to suitable habitat within Lake Whatcom. Typical impacts associated with the clam should be expected. These include changes in species richness, especially changes in native filter feeder concentration as well as changes to phytoplankton density, and alterations to the seston nutrient load because of burrowing and biological functions associated with C. fluminea
Naturally occurring aqueous arsenic and seawater intrusion on Lummi Island, WA by Erica Martell( )

2 editions published in 2010 in English and held by 2 WorldCat member libraries worldwide

Two different types of groundwater contamination may be present in the aquifers on northern Lummi Island, Washington: naturally occurring arsenic and seawater intrusion. Freshwater on northern Lummi Island is stored in bedrock and unconsolidated glacial sediments. The naturally occurring arsenic, sourced from an undetermined stratigraphic layer, varies spatially throughout the island. Additionally, seawater may be intruding into the groundwater supply, which is the primary source of drinking water for the residents of the island. The process of mobilization of the naturally occurring arsenic and the extent of the seawater intrusion has not been fully explored. The purpose of my study was to determine the geochemical, physical, and seasonal influences on concentrations of arsenic and major ions on Lummi Island. I collected water samples and made in situ measurements from wells distributed throughout Lummi Island for geochemical analysis. Statistical analysis was used to test for a relationship between arsenic concentrations and geochemical factors or season. The speciation of arsenic in the groundwater was determined by plotting pH and redox potential measurements on an arsenic species stability diagram. Whole-rock chemical analysis was used to investigate the bedrock source of the arsenic. The extent of the seawater intrusion was determined using major ion analysis, and the source of the ions was interpreted using Piper diagrams. The relationship between aquifers, major ions, and seasonality was explored using multivariate statistical analysis. Whole rock analysis indicated that the highest arsenic concentration was in the sample taken from the Chuckanut conglomerate. When Eh and pH field measurements were plotted on an arsenic stability diagram, arsenate was revealed as the dominant species in the groundwater. Speciation calculations in PHREEQC supported the conclusion that arsenate was the dominant species in most water samples. No wells indicated seawater intrusion and some plotted in the freshening region of the Piper diagram. Wells that plotted in the freshening area of the Piper diagram were more likely to have higher arsenic concentrations. Bivariate analysis, principal component analysis, non-metric clustering and Piper plots failed to show a difference in the measured variables between the April and August samples. A positive correlation was found between specific conductance, Na+, Cl- and total alkalinity and dissolved arsenic, and a negative correlation was found between Ca2+ and Mg2+ and dissolved arsenic. No correlation was observed between dissolved arsenic and Fe or Mn. Multivariate statistics indicated a correlation between the presence of major ions and the dissolved arsenic concentrations. The positive correlation between alkalinity and dissolved arsenic, negative correlations between Ca2+ and Mg2+ and dissolved arsenic, and no correlations with Fe or Mn is consistent with an arsenic release through a desorption process. The presence of dissolved carbonate and bicarbonate is indicative of a chemical weathering process, which could lead to arsenic desorption, and the charge on Ca2+ and Mg2+ ions can facilitate the adsorption and desorption of dissolved arsenic. Since the Chuckanut sandstone had the highest dissolved arsenic concentrations, a chemical weathering process is most likely occurring within this stratigraphic layer. No wells in this study exceeded the SMCL (Secondary Maximum Contaminant Level), nor did any wells experience a statistically significant fluctuation in chlorides between the April and August sampling seasons. When the major ions were plotted on a Piper diagram, all of the wells plotted in either the "fresh" or the "freshening" part of the diagram; none of the samples plotted in the "intruding" or "intruded" area. Because there was no evidence that the wells in my study were experiencing seawater intrusion, the salts must be released from another source. This relationship between major ions and dissolved arsenic was supported by the multivariate statistical tests principal component analysis and linear discriminant analysis. The principal component analysis successfully classified arsenic into high and low groups, and once trained with a subset of the data, the linear discriminant analysis divided arsenic into high or low categories. The relationship between the major ions and dissolved arsenic can be interpreted from a Piper diagram when the high dissolved arsenic concentrations ([As]>0.07 mg/L) is color coded. These water samples all plotted in the freshening region of the Piper diagram. Because chlorides and dissolved arsenic were positively related, specific conductance, used as a proxy for chlorides, could be used as a rough indicator for arsenic
The vocal breeding behaviour of harbour seals (Phoca vitulina) in Georgia Strait, Canada : temporal patterns and vocal repertoire by Katriana A Nikolich( )

2 editions published in 2015 in English and held by 2 WorldCat member libraries worldwide

During the breeding season, male harbour seals (Phoca vitulina) produce underwater calls used in intra-sexual competition and advertisement. One call type, called a roar, has been documented in every population of this species that has been studied. Because calls vary in structure and temporal patterns among populations, it can be inferred that regional vocal dialects may exist, and that the influence of local environmental and biological conditions may affect the timing of calls. Breeding calls have only been studied in relatively few locations worldwide; however, the effect of ambient noise on the underwater vocal behaviour of harbour seals has not been studied. I investigated the temporal patterns, structure and complexity of harbour seal breeding calls at Hornby Island, British Columbia. Underwater recordings were made near the south end of Hornby Island in the summer breeding season of 2014 using a single omnidirectional hydrophone while concurrent visual observations were conducted at a nearby site on shore. I investigated the relationships between roars per hour, tide level, ambient noise and time of day. Logistic regression showed that roars were over eight times more likely to be heard during night-time hours than during the day. When roars were heard, roar number was most influenced by time of day and the progression of the breeding season, with more roars heard later into the breeding season. Roar density was inversely related with ambient noise; however, ambient noise and time of day were highly auto-correlated, and therefore the effects of these two variables could not be assessed independently. Whereas harbour seal call timing in other areas has been attributed to tidally-driven haul-out patterns, the tide level at Hornby Island did not statistically correlate with roar density. I hypothesize that ambient noise may be a cause of the strong diel pattern of call density at Hornby Island, and suggest further study to determine the mechanistic link between ambient noise cycles and calling behaviour. Four breeding call types were identified, one of which was the 'roar' call described in every population that has been studied. The structure of the roars at Hornby Island was comparable to those of other populations, but displayed wide variation in several parameters. Each of the three non-roar call types were distinguished from roars qualitatively by aural-visual classification, and quantitatively by trained linear discriminants analysis (LDA). Agreement between these two classification systems was 88%, suggesting that the four call types were distinct. The three non-roar call types contained five call subtypes which were also identified through aural-visual and LDA classification. Agreement was slightly lower at 74%, but more variable, suggesting that some call subtypes were more distinct than others. One non-roar call type, the sweep, was distinct from any call previously described for harbour seals worldwide. I suggest that more than one of these call types are used by each individual, supporting the results of a previous study in California which identified several call types produced by harbour seals. If this is the case, then the vocal breeding repertoire of harbour seals at Hornby Island is more complex than that of most previously studied populations. Further study of this population with the ability to localize calls and identify individuals is required to support or refute the hypothesis that individual harbour seals at Hornby Island produce several call types
An analysis of agricultural land use effects on surface water quality in Skagit County streams by MarySutton Carruthers( )

2 editions published in 2012 in English and held by 2 WorldCat member libraries worldwide

Nonpoint source pollution is a concern in many streams nationwide. Puget Sound cleanup efforts have increasingly focused on targeting nonpoint sources of pollution, including nutrient and bacterial sources resulting from agricultural activities. Skagit County, Washington hosts a robust compilation of agricultural activities from large scale row crops and dairy operations to small hobby farms. It is also home to the Skagit River, the most important river system for Puget Sound salmon, and Samish Bay, the largest shellfish growing area in the north Puget Sound. Enormous efforts have been made to assess the health of Washington's waterways and to find an effective way to ensure clean water without threatening the historic agricultural sector. The Skagit County government established a monitoring program in 2003 for the express purpose of assessing agricultural effects on streams. Surface water quality data from 40 sites on 28 streams, collected from 2003-2011 as part of this program, were used in these analyses. The objective of this research was to augment Skagit County water quality reports in order to determine the influence of agricultural land-use and precipitation on regional surface water quality. Median fecal coliforms, salinity, and turbidity were higher at sites at the downstream end of agricultural areas as compared with upstream sites, and dissolved oxygen concentrations were lower. Sites downstream from agricultural activities were more likely to have detectable levels of total suspended solids, orthophosphate, ammonium, and total Kjeldahl nitrogen than midstream, upstream, or reference sites. Precipitation was only correlated with fecal coliforms at a quarter of the sites, though precipitation events were associated with higher median fecal coliforms at downstream sites. Land-use characteristics were more deterministic of median fecal coliforms than were inherent watershed characteristics
Microcosm study of the accumulation of benzo(a)pyrene by Lake Whatcom phytoplankton by Shannon Ashurst( )

1 edition published in 2003 in English and held by 2 WorldCat member libraries worldwide

I developed a preliminary method for measuring in situ benzo(a)pyrene (BaP) accumulation by phytoplankton using laboratory studies and natural assemblages of Lake Whatcom (Bellingham, WA) phytoplankton. Most phytoplankton BaP accumulation studies use laboratory manipulations of algal cultures, which are often monocultures rather than natural communities. Such research, while it illustrates general trends and observations, does not provide practical methodology for using phytoplanktonic bioindicators at specific sites. I intended this thesis to bridge the gap between laboratory-based studies and in situ biomonitoring. Developed using a sequence of smaller experiments, the method attempted to balance both efficiency and high analyte recovery in measuring BaP accumulation and in characterizing the phytoplankton community under investigation. Natural phytoplankton cultures were concentrated using a Schindler trap and were exposed to BaP under laboratory conditions. Phytoplankton were characterized using three different parameters - chlorophyll a, abundance, and biovolume. The distribution of BaP was evaluated throughout the phytoplankton microcosms. Approximately 53% of the BaP was recovered from the microcosms, with the diatom-dominated phytoplankton communities showing a strong tendency to accumulate BaP. The method successfully recovered measurable quantities of BaP from natural phytoplankton communities and met preliminary method validation criteria. Following investigation of more effective phytoplankton concentration techniques, this method could be applied to sites with prior exposure to BaP. Given the overall shortage in research regarding in situ measurement of other hydrophobic organic chemicals in aquatic bioindicators, the method could also be adapted for use with chemicals other than BaP
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Environmental engineering
English (58)