WorldCat Identities

Helfield, James M.

Overview
Works: 26 works in 50 publications in 1 language and 53 library holdings
Genres: Academic theses 
Roles: Author
Classifications: LD5778.9,
Publication Timeline
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Most widely held works by James M Helfield
Interactions of salmon, bear and riparian vegetation in Alaska by James M Helfield( Book )

3 editions published between 2001 and 2002 in English and held by 4 WorldCat member libraries worldwide

Seasonal and age-based aspects of diet of the introduced redside shiner (Richardsonius balteatus) in Ross Lake, Washington by Carmen A Welch( )

2 editions published in 2012 in English and held by 3 WorldCat member libraries worldwide

This study investigates the introduced population of the Redside Shiner (Richardsonius balteatus) in Ross Lake, Washington. The Redside Shiner was introduced to Ross Lake around 2000 and in the summer months, can be found in densities of hundreds per cubic meter in the shallow areas of Ross Lake. Ross Lake is a protected thirty-five and a half kilometer long reservoir in North Cascades National Park with cold, clear water of exceptional quality. Fish native to Ross Lake include: Bull Trout, Dolly Varden and Rainbow Trout. It is a commonly held belief that the introduced Redside Shiner have no negative effect on the native fish in Ross Lake and that they benefit the native fish as a source of prey. However, previous studies in other lakes have reported reduced growth and survival of juvenile Rainbow Trout as a result of the introduction of the Redside Shiner. Considering the conflict about the potential effects of the introduced Redside Shiner in Ross Lake, the two main goals of this study were to determine what the Redside Shiner in Ross Lake consumes and to evaluate the potential threat of long-term impacts to the native fish in Ross Lake. Samples were collected from three different locations in the lake across all seasons. Age was determined for 178 Redside Shiners and the stomach contents of 271 Redside Shiners were evaluated. Samples were collected to represent northern, middle and southern areas of Ross Lake. Collection occurred in the winter, spring, summer and fall. Age determination showed the samples consisted of Redside Shiners ages 0 to 6. Regardless of location, season and age, zooplankton and insects are the most important diet categories to the Redside Shiner in Ross Lake both in terms of frequency of occurrence and percent volume of total diet. They also consume oligochaetes, cestodes, algae and other unidentifiable incidental items such as wood, sediment and what appears to be plastics, however none are of much importance. Based on my findings, the Redside Shiner likely competes with the native fish in Ross Lake for food. The competitive juvenile bottleneck theory explains the potential for a predator to be negatively impacted from its prey due to competition with its juveniles. Like the Redside Shiner in Ross Lake, the juvenile native fish may also depend primarily on aquatic insects and zooplankton. Unless food resources are partitioned spatially and seasonally, the competitive juvenile bottle neck theory holds merit in Ross Lake and direct competition between the introduced Redside Shiner and the native fish seems likely. Based on back-calculated ages of the Redside Shiner in Ross Lake, this population seems to be stable with the potential to persist in high numbers into the future, forecasting that the risk for competition may also persist into the future. Considering the potential for competition now and into the future, further research is required to generate information about the dietary habits of the juvenile native fish, their spatial distribution and how they use the different habitats in Ross Lake
Modeling relative effects of riparian cover and groundwater inflow on stream temperature in lowland Whatcom County, Washington by Sarah Harper-Smith( )

2 editions published in 2008 in English and held by 3 WorldCat member libraries worldwide

Many Pacific Northwest streams have water temperatures that exceed thermal thresholds for salmonids. Supporting and maintaining streams with temperatures below these thermal thresholds requires an understanding of the relationships between the main factors influencing stream temperatures. This study examined the relative effects of two of these factors, riparian canopy cover and groundwater inflow, on stream temperatures at the reach scale. I measured stream temperature, net groundwater exchange, and riparian canopy cover levels in 10 different study reaches designed to comprise a factorial combination of reaches with vegetated and unvegetated riparian buffers, as well as gaining and not-gaining groundwater. I then modeled stream temperatures in each reach with the SSTEMP stream temperature model, and compared model-predicted temperatures to measured stream temperatures during the warmest part of the summer. Finally, I manipulated the model to examine the relative impacts of riparian canopy cover (0-100%) and groundwater inflow (0-50%) on predicted stream temperatures. SSTEMP predicted daily mean reach temperatures well across the range of conditions studied here, although it overpredicted daily maximum temperatures. Model manipulations of groundwater inflow and canopy cover levels showed consistent trends in affecting stream temperatures. Under peak summer conditions and "base" groundwater (0%) and canopy cover (0%) conditions, predicted mean stream v temperatures warmed by an average of ~ 4°C across all streams. Full canopy cover and 50% groundwater inflow each reduced this predicted warming by ~ 2.5°C when manipulated independently. However, only the combination of both high canopy cover and groundwater inflow actually reduced predicted mean stream temperatures within the study reaches. In contrast, canopy cover had much stronger effects on modeled maximum stream temperatures than did groundwater inflow. Under peak summer conditions, 100% canopy cover reduced predicted downstream warming of daily maxima by ~ 10°C, while 50% groundwater inflow did so by only ~ 2°C compared to base conditions. The results of this study affirm that both canopy cover and groundwater inflow play significant roles in minimizing stream temperatures in summer, and both should be considered when making restoration, land use, and other management decisions
Factors affecting the distribution and abundance of the Salish sucker (Catostomus sp.) : an endemic and endangered transboundary fish population by Nathaniel S Lundgren( )

2 editions published in 2013 in English and held by 2 WorldCat member libraries worldwide

The Salish sucker (Catostomus sp.) is a recently described endemic fish species with a patchy distribution and a narrow geographic range in western Washington and southwestern British Columbia. In this study I examined populations within the Nooksack River watershed, attempting to elucidate the environmental factors contributing to observed patterns of distribution and abundance. I hypothesized that hypoxic and hyperthermic conditions during the summer months would restrict Salish sucker distribution. I tested this hypothesis by measuring dissolved oxygen concentrations, temperature, and Salish sucker abundance and movement at eight sites in the Bertrand Creek and Fishtrap Creek sub-basins. The results of this study did not support my original hypothesis; instead it seems more likely that physical habitat characteristics rather than water quality exert greater influence in patterns of abundance and distribution. My findings emphasize the importance of maintaining the quality and connectivity of habitat for Salish sucker conservation
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
Age determination of the sixgill shark from hard parts using a series of traditional and novel approaches by S. Jeffrey Campbell( )

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

Necessary to the management of any species of fish is the ability to determine age in individuals. Age information is used to establish growth rates, longevity, age at maturity, and population age structure, and to predict how population demographics will change over time. For most species of fish, reliable aging techniques have been in use since the early 20th century. Most boney fish are aged by counting bands of calcium phosphate hydroxyapatite that form over time in skeletal hard parts such as otoliths, fin-spines, and scales, which can be used as proxies for age in years. Fishes in the Class Elasmobranchii lack otoliths and have skeletons composed of cartilage, which often do not incorporate enough calcium to enable enumeration by traditional aging methods that rely on light microscopy, in some cases aided by enhancement techniques such as histological staining. For these fishes, alternative methods and aging structures are used to identify and enumerate annual patterns in calcium deposition. The aging structure of choice for most elasmobranches is the vertebral centrum, where bands of calcium are deposited that can be used as proxies for age in years. A few deep-dwelling species of Elasmobranchii, such as the sixgill shark (Hexanchus griseus,) have as yet defied efforts at age determination, inhibiting efforts to implement science-based management plans. This study has attempted to identify alternative aging structures that may incorporate seasonally-mediated concentrations of elements or isotopes into cartilage. Once identified, these structures were subjected to two recently developed methods of elemental microanalysis, energy dispersive X-ray spectroscopy (EDAX), and laser ablation, inductively-coupled, plasma mass spectrometry (LA-ICP-MS), in an effort to develop an aging method for H. griseus, and potentially other poorly calcified elasmobranchs. In addition, it has also used two traditional, histological staining methods, Von Kossa's AgNO3, and Alizarin Red-S and applied them to these non-traditional aging structures. This study identified regions within the cartilaginous skeleton of H. griseus that lay down systematic banding patterns. These patterns were visually detected using AgNO3 staining enhanced light microscopy, as well as by periodic oscillations in isotopic concentrations for 24Mg, 88Sr, 107Ag, and 109Ag that were detected through the use of LA-ICP-MS. Future research in this field will need to verify if these bands are deposited on an annual basis. Methodologies must be developed for verification, and validation of these procedures to determine if the band patterns identified by either of these methods have utility for age determination in this and other poorly calcified species of elasmobranchs
Alternative foraging strategies among brown bears (Ursus arctos) fishing for chum salmon (Oncorhynchus keta) at McNeil River, Alaska by Ian D Gill( )

2 editions published in 2011 in English and held by 2 WorldCat member libraries worldwide

Previous research on the fishing behavior of bears (Ursus spp.) along salmon streams suggests that dominant individuals forage more efficiently than their competitors; specifically, large adult males are the most efficient foragers at a given stream due to their ability to dominate the most productive locations. I tested this hypothesis by observing 26 individual brown bears (U. arctos) fishing for chum salmon (Oncorhynchus keta) at McNeil River, Alaska, over 33 days during the summer of 2010. In contrast with previous findings I did not observe strong relationships between the foraging efficiency of individual bears and the frequency with which they engaged in dominance-related behaviors (e.g., displacing competitors, stealing fish, using more productive locations). While some individuals seemed to employ dominance as a strategy to achieve high catch rates, other individuals achieved high foraging efficiency by employing alternative foraging strategies that did not involve dominance-related behaviors. My observations suggest that bears at McNeil River employ a variety of fishing strategies, of which dominance-related behavior is but one alternative. I suggest that where foraging efficiency is concerned, an individual bear's ability to develop an effective foraging strategy may be more important than its social dominance. My findings open the door to intriguing questions for future research into which physical or cognitive traits lead to the development of successful foraging strategies among brown bears fishing for salmon
Dendrochronology of seaside juniper (Juniperus maritima) by Dustin Gleaves( )

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

Seaside juniper (Juniperus maritima) is a recently discovered tree species endemic to the Salish Sea region and is an as yet unutilized dendrochronological resource. This study reports the first dendrochronological investigation of the species. We sought to determine if Seaside junipers are capable of crossdating, a requirement for consideration as a dendrochronology study species, and to identify correlations between instrumental climate records and radial growth to determine climate-growth response. We collected tree core samples from Seaside juniper in five sites throughout the San Juan Islands and nearby mainland. Samples collected from one of five sites successfully crossdated. Bootstrapped correlation function analysis found the dominant growth-limiting factor of Seaside junipers is growing season minimum temperatures in the prior year (r = 0.547) and in the current year (r = 0.524), potentially indicating a common growth-limiting factor of either temperature or solar irradiance. Understanding this climate-growth relationship will aid in development of a conservation strategy for this rare and endemic species
Comparing soil datasets with the APEX model : calibration and validation for hydrology and crop yield in Whatcom County, Washington by Andrew M Monks( )

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

Controlling pollution from agricultural lands is a priority for improving watershed health. Best management practices (BMPs) recommend strategies such as riparian buffers and altered fertilizer application timing and rates for reduction of nutrient and sediment export from agricultural watersheds, but BMP effectiveness in nutrient retention can vary greatly depending on differences in crops, soils, and topography. Conducting nitrogen (N) and phosphorus (P) measurements in all BMP projects is generally not feasible, so well-validated models can help estimate benefits on the watershed scale. This project uses the Agricultural Policy/ Environmental Extender (APEX) model to simulate crop yield, streamflow, and surface runoff in a small watershed in Whatcom County, Washington, to prepare the model for future use in estimating nutrient and sediment retention benefits by BMPs. The APEX model requires detailed inputs for soils, climate, cropping system, and agricultural management; outputs must be calibrated and validated against existing environmental data. No current consensus exists as to the ideal set of soil data for the APEX model. I tested the APEX model for three different soils datasets: the Soil Survey Geographic Database (SSURGO), the National Cooperative Soil Survey (NCSS), and the Nutrient Tracking Tool (NTT), to determine the best dataset to use in terms of ease of use and model fit. I modeled the northern Kamm Creek watershed, a 227 hectare watershed that contains a diverse representation of Whatcom County cropping systems. As the first APEX modelling effort in western Washington, this study investigated parameters for blueberry and raspberry, two crops new to the APEX model, while testing model performance with three different sets of soils data. I manipulated key parameters in two of the datasets to evaluate their effects on hydrology and yield. The model performed well for streamflow and surface runoff across all soils during calibration, with satisfactory validation for surface runoff, but not streamflow. Performance for crop yields, however, varied across both crop type and soil data sets. Simulated crop yields fell within 10% of county-reported average yields for four of the five soils for blueberry, raspberry, and corn silage crops, whereas NTT soils drastically underestimated yields of both berry crops. I recommend applying the SSURGO soils dataset to future APEX modelling in Whatcom County, as it had the best model fit for hydrology and crop yields. Further recommendations are made for obtaining data to parameterize, calibrate, and validate the model to assure accuracy for future APEX modelling efforts
Emergent contaminants and effects on field-exposed chinook salmon and cutthroat trout in the Stillaguamish Watershed, WA. by Jody M Pope( )

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

Contaminants of emerging concern (CECs) are chemical compounds that have no regulatory standards, are recently discovered in the natural environment due to improved analytical methods, and can potentially cause adverse effects to aquatic life. More specifically, CECs affecting fish communities include endocrine disrupting chemicals (EDCs), which can produce developmental abnormalities or alter the epigenome, potentially affecting survival and reproductive success. This study assessed CEC occurrence as well as toxicological and epigenetic responses of caged, hatchery-reared Chinook salmon (Oncorhynchus tshawytscha) and field-collected, wild, resident cutthroat trout (O. clarkii) at sites representing different land uses in the Stillaguamish River watershed, Washington State. This study was comprised of two experiments over two years: the first hatchery-reared juvenile Chinook salmon were caged for 28-days and the second, wild, resident cutthroat trout were captured via electroshocking. This study analyzed presence and concentrations of CEC analytes in stream water using Polar Organic Chemical Integrative Sampler (POCIS) devices across all study sites. The study analyzed chemical contaminants in fish tissues (i.e., liver and gall bladder), as well as vitellogenin (VTG) protein in blood plasma. Gene expression was analyzed using microarray technology. Contaminants of emerging concern occurrences and concentrations were generally low, although somewhat higher at sites receiving urban or agricultural runoff or wastewater treatment effluent. Chemical analyses indicated low CEC concentrations in sampled tissue from both Chinook and cutthroat, as most analytes were not detected above reporting limits. Vitellogenin protein results revealed few measurable detections. Analysis of gene expression also suggest overall weak responses relative to controls. Overall, this study found some CEC pollution, mostly at sites influenced by urbanization, agriculture or wastewater effluent, but there was little to no indication that CECs are affecting fish health in the Stillaguamish watershed
Mycorrhizal availability in the basin of Lake Mills and influence on colonization and growth of Salix scouleriana under drought stress by Andrew Cortese( )

2 editions published in 2014 in English and held by 2 WorldCat member libraries worldwide

In September 2011, the removal of two dams on the Elwha River was initiated as part of the largest dam removal project in history. The drainage of Lakes Mills and Aldwell exposed 300 hectares of reservoir bottom. Reestablishment of native vegetation in the lakebeds is critical for the restoration of ecosystem function, but the reservoir sediment composition may inhibit revegetation due to poor water holding capacity. It is known that mycorrhizae can ameliorate the effects of drought stress for host plants but little is known about their availability in the Lake Mills basin. In my project, I first assessed the abundance of arbuscular mycorrhizal fungi (AMF) and ectomycorrhizal fungi (EMF) in the Lake Mills basin. I also conducted a greenhouse bioassay in which I grew willows in potting soil and Elwha silt with different treatments of mycorrhizal inoculum. I then drought stressed the willows in order to replicate the expected summertime conditions in the Lake Mills basin. There are some viable AMF and EMF in Lake Mills, but with higher abundance near the forest and high variability in the soil. There was no effect of mycorrhizal inoculum on growth of willows and no effect of the Elwha silt on formation of AM and EM. My results suggest that willows are not dependent on mycorrhizal fungi and can establish independent of mycorrhizal propagules. Mycorrhizae can then form with willows when propagules are available, boost the mycorrhizal infectivity of the soil and then subsequently facilitate the establishment of other plant species
Elwha River sediments : phosphorus dynamics under diverse environmental conditions by Emily Cavaliere( )

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

Two large dams on the Elwha River, on the Olympic Peninsula in Washington State, are scheduled for removal in 2011. Removing the Glines Canyon Dam will release up to 10.6 million cubic meters of sediment from Lake Mills. The sediments will be exposed to new physical and chemical conditions and be redistributed throughout the ecosystem. In the summer of 2008, sediment samples were taken from the above-water delta and the submerged lake bottom of Lake Mills to identify initial physical and chemical characteristics relating to the variable status of phosphorus in the sediments. The sediments were analyzed for different forms of phosphorus (P), amorphous iron (Fe), carbon (C), nitrogen (N), and particle size. The lake sediments had greater concentrations of all elements analyzed and had smaller mean particle size compared to the delta sediments. A two-week incubation of sediments under various environmental conditions indicated P release was not affected by atmosphere type. For delta sediments, P release was greater in freshwater than saltwater throughout the incubation, while for lake sediments this occurred only initially. Overall, the magnitude of P release was similar for the two sediment types. An isotherm study performed in conjunction with the incubation study revealed that both the lake and delta sediments could immobilize large quantities of added P, but lake sediments maintained dissolved P concentrations at half the level of delta sediments. Managers could use the information found in this study to help understand the phosphorus release and immobilization patterns in sediments after dam removal
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
Effectiveness of salmon carcass analogs as a form of nutrient enhancement for juvenile coho salmon (Oncorhynchus kisutch) in three lower Columbia watersheds by Matthew T Sturza( )

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

Adult Pacific salmon exhibit a form of parental care after spawning and perishing by depositing a subsidy of marine derived nutrients (MDN) that may be incorporated into the stream food web and feed juvenile salmon. Adult salmon populations have significantly declined since the late 19th century, thereby reducing the amount of MDN within Pacific Northwest Streams. This loss in nutrients within stream food webs may be limiting the growth and survival of juvenile salmon and therefore reducing the population sizes of adult salmon. One strategy to mitigate for nutrient deficiencies within a stream is the use of salmon carcass analogs (SCA), pellets composed of pulverized and pasteurized marine forage fish. We investigated the effectiveness of SCA in enhancing the size and abundance of juvenile coho salmon within a complex of three watersheds (Abernathy, Germany, and Mill Creek) that empty into the lower Columbia River near Cathlamet, WA. SCA applications occurred in the fall (2010-2013) on Germany Creek and in the spring (2013-2015) on Abernathy Creek, while Mill Creek served as a reference watershed and did not receive SCA applications. We periodically gathered samples of periphyton, macroinvertebrates, and juvenile coho (fin clips) before and after SCA application at approximately two month intervals. Juvenile coho were also sampled for fork length and weight. Samples were taken at three sites at the lower, middle, and upper extent of adult coho spawning within each watershed. During the final sampling event of each year, while juvenile coho were outmigrating, fin clips were taken at smolt traps located near each river's confluence with the Columbia River. Data from smolt traps were used to estimate the average fork length and abundance of juvenile coho during each year of this project. To evaluate the timing and extent of nutrients from SCA being incorporated into the stream food web, samples were processed and analyzed for [delta] 15N, a measure of the abundance of the heavier isotope of nitrogen that occurs more abundantly in the marine environment. Seasonal trends of [delta]15N in periphyton, macroinvertebrates, and juvenile coho, as well as seasonal trends of juvenile coho fork length and weight were compared between fertilized and unfertilized watersheds. We detected SCA effects on seasonal trends of macroinvertebrate and juvenile coho [delta]15N for the fall and spring treatments, indicating SCA nutrients were incorporated by these communities. We detected SCA effects on the seasonal trends of juvenile coho fork length and weight for the spring treatment, but not for the fall treatment. We could not detect SCA effects on seasonal trends of periphyton [delta]15N for either the fall or spring treatment, potentially due to smaller than needed sample sizes. Overall the effect of fall SCA application was to disrupt the seasonal trend of [delta]15N values among trophic levels by causing an increase in [delta]15N during the late fall/early winter when values are normally decreasing. The effect of spring SCA application was to enhance the seasonal trend, causing increases in [delta]15N values greater than those seen in the absence of SCA applications. Comparing juvenile coho sizes and abundances between years with and without SCA application and between fertilized and unfertilized watersheds indicated that neither the fall or spring treatment had a significant effect on coho growth and survival. Where SCA are to be used as a salmonid recovery tool, we recommend that careful watershed selection and subsequent monitoring be employed to ensure investments are worthwhile
The associations of epiphytic macroinvertebrates and aquatic macrophytes in Canyon Lake, WA by Jesse T Klinger( )

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

Macroinvertebrate abundances on six dominant macrophytes taxa were compared in Canyon Lake, Washington to determine whether there were patterns of association with macrophyte type or among assemblages of macroinvertebrates. Macrophytes and associated epiphytic macroinvertebrates were collected during August 2016. The dominant macrophyte distribution and lakes bathymetry were mapped in July 2016. The dominant macrophytes included Equisetum fluviatile, Fontinalis antipyretica, Potamogeton natans, Potamogeton epihydrus, Ranunculus aquatilis, and Vallisneria americana. Other non-dominant macrophytes included: Sparganium angustifolium, Sphagnum mosses, Nuphar polysepala, Characeae (stonewort), Isoetes (quillwort) and Potamogeton pusillus. Macroinvertebrate taxa were identified to the lowest practical taxonomic resolution; the dominant macrophytes were identified to species; other non-dominant macrophytes were identified to the lowest practical resolution. Water quality samples were collected in June, July and August 2016 and were analyzed for temperature, dissolved oxygen, pH, conductivity, turbidity, alkalinity, chlorophyll, ammonium, nitrate+nitrite, total nitrogen, soluble reactive phosphorus, and total phosphorus. The summer water quality in Canyon Lake was characterized by warm water temperatures (11.4 - 20.2 °C) and high dissolved oxygen concentrations (8.6 - 9.9 mg/L) in the upper water column. The lake began to stratify in June, and by late August the dissolved oxygen was <2 mg/L in the deepest part of the lake. The lake had soft, poorly bu
Assessment of riparian conditions in the Nooksack River Basin with the combination of LiDAR, multi-spectral imagery and GIS by Erica M Capuana( )

2 editions published in 2013 in English and held by 2 WorldCat member libraries worldwide

Riparian areas are a complex component of stream ecosystems and provide critical habitat for Pacific salmon (Oncorhynchus spp.). Comprehensive techniques are needed for assessing riparian areas that can be used on small and large regional scales. I examined the application of airborne LiDAR and high resolution multi-spectral imagery from the World View-2 (WV-2) satellite to analyze riparian landcover and riparian forest structure in the Nooksack River Watershed. I employed an object-oriented approach to segment the imagery into meaningful objects consisting of groups of pixels. I examined the advantages of the four additional spectral bands from the 8-Band World View-2 Image compared to the traditional four spectral bands provided from conventional high resolution multi-spectral imagery. Using the Random Forest algorithm, I developed classification and regression models to predict the features of interest across the study area. The classification results from the 8-Band WV-2 image were improved over the traditional 4-Band WV-2 image that is comparable to other high resolution sensors such as IKONOS and Quickbird. Analyzing the combined LiDAR and 8-Band WV-2 spectral data improved the results for landcover classification but did not improve the results for riparian forest structural predictions. However, the results generated from the LiDAR only image was comparable to the 8-Band WV-2 spectral imagery at classifying forest classes and remarkably better at predicting forest structure data. The overall results indicate that classification of forested cover type and structural properties of riparian forest stands can be determined accurately for relatively large study areas with LiDAR-based approaches. From the final LiDAR image output, I applied the models to categorize the riparian forest based on forest class, size, and density to show one application of the results generated in this study. The categorized map provides a tool to prioritize restoration and preservation needs within the riparian forest landscape in the Nooksack River Basin study area
Plant community and nutrient development within four estuary restoration sites in Kitsap County, Washington by Shannon M Call( )

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

Coastal wetland ecosystems are some of the most productive ecosystems on the planet and link freshwater and marine environments. Coastal wetlands provide invaluable ecosystem services such as carbon sequestration, storm abatement, biogeochemical cycling, and water filtration. However, estuaries affected by physical barriers, such as culverts, experience reduced hydrological inputs and reduced connectivity above and below the site of impact. Loss of connectivity results in loss of ecosystem function such as carbon and nitrogen cycling. We investigated soil nutrients and vegetation composition of estuarine communities in four estuary restoration locations in Kitsap County, Washington and the following questions were addressed: 1) is there a linear trajectory in recovery of soil carbon and organic matter due to length of time since ecological restoration (i.e. culvert removal), 2) is there a recovery of soil nutrients optimal for plant growth, 3) does plant species diversity increase over time, 4) will plant communities homogenize between restoration location (i.e., above or below the culvert) over time, and 5) does time since restoration affect invasibility? Differences in percent soil carbon and organic matter existed among sites. The carbon-to-nitrogen ratio was highest below the culvert restoration location at the newest post-restoration site, indicating nitrogen deficiency. Percent soil carbon and organic matter initially dropped in newly restored sites, and was highest at the pre-restoration site (pre). Soil nutrients were analyzed and nitrogen, potassium, magnesium, sulfur, boron, copper, and manganese were positively correlated with dried plant biomass. Potassium, magnesium, boron, iron, and manganese were all below common soil ranges. A total of 65 plant species were surveyed, with a significant increase in species richness and diversity (H') at the oldest restoration site, with decreasing differences in diversity as age since restoration increased. Community composition was dominated by pickleweed (Salicornia virginica), colonial bentgrass (Agrostis capillaris), and fat hen (Chenopodium album) among all sites. Nine invasive species were surveyed, but were not significantly different within and among sites. The pre-restoration site (pre) showed the lowest species richness above the culvert and the intermediate site had the highest, with a trend of increasing species richness over time. The oldest post-restoration site had the highest diversity using the Shannon-Wiener (H') diversity index. Locations (above or below) were significantly different from one another determined by principal component analysis (PCA), analysis of similarity (ANOSIM), and similarity percentages (SIMPER). The results indicate salinity is the largest environmental driver of vegetative assemblages, and homogenization of plant communities between locations (above vs. below) has not occurred at any site
Salmon in the trees : an assessment of a dendrochemical technique for detecting marine-derived nitrogen in riparian tree rings by Jody Gerdts( )

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

Quantifying the relationship between salmon escapement and riparian tree-ring [delta]15N could contribute greatly to understanding trends in historic salmon abundance. Such an understanding could have far-reaching consequences for understanding historic carrying capacities of river systems and help guide future restoration efforts. This study investigates the reliability of using naturally occurring isotopic variations in annual tree rings to produce quantifiable estimates of historic salmon runs. Three study areas with temporal and spatial changes in salmon spawning abundance were examined. I found that currently available techniques for removing mobile nitrogen are not sufficient to overcome problems associated with radial mobility, as indicated by enrichment of tree rings formed prior to a labeled fertilizing experiment. Tree ring [delta]15N signatures failed to capture known changes in salmon abundance above a migration barrier on the Skykomish River but were related to historic escapement ranges at on Icicle Creek with tree-cores downstream from an historic migration barrier showing an elevated [delta]15N signature compared to upstream. While a relationship between tree-ring [delta]15N and salmon abundance may exist, thesis relationships may be obscured by the inter-radial mobility of nitrogenous compounds and confounded by local nitrogen cycle nuances, or by species specific processing of N
Sediment and vegetation monitoring during a levee removal project on the Stillaguamish River Delta at Port Susan Bay, WA by Alec Barber( )

2 editions published in 2014 in English and held by 2 WorldCat member libraries worldwide

Sea levels around the world are on the rise in due to the effects of climate change. Coastal wetlands and estuaries are at risk of being submerged as water levels continue to increase, unless they can move inland or gain surface elevation. These wetland systems provide vital ecosystem services that would be difficult or impossible to provide by other means. In the Puget Sound, Washington, 80% of the original estuarine and coastal wetland habitat has been replaced by human infrastructure, making the monitoring, preservation, and restoration of the remaining stock important both ecologically and economically. The objective of this project was to monitor the restoration of an estuarine system on the Stillaguamish River delta. The project involves the removal of levees and reintroduction of tidal flow into a subsided farmland that was formerly part of the estuary, and to determine the sustainability of the Stillaguamish River delta and similar Puget Sound estuaries with rising sea-levels. The scope of this monitoring project includes the installation and yearly sampling of surface elevation tables (SETs), vegetation surveys and quantification of the net primary productivity (NPP) within the leveed area, immediately outside the levees, in an adjacent area outside the farmland, and within an un-leveed reference site across the main river channel. SET sampling, before the levee removal, revealed a positive trend in elevation gain at 8 of the 11 SETs of over 1 cm/year, well above current rate of RSLR at 0.19cm/year. Sediment markers revealed that most of that gain can be attributed to sediment accretion, indicating adequate sources of sediment and therefore sustainability of the estuary under current rates of sea level rise. Primary productivity sampling in the late summer of 2012 yielded an average of 420 DW(g)/m²/year in the high marsh and 327 DW(g)/m²/year in the low marsh sites. Vegetation consisted predominantly of Schoenoplectus americanus, Schoenoplectus acutus, and Schoenoplectus maritimus, with elevation delineating the greatest shifts in community structure and abundance. The exception to this was within the portion of leveed farmland, where surface elevations were below the surrounding estuary and vegetation consisted primarily of a Schoenoplectus americanus monoculture
Phytoplankton ecology in four high-elevation lakes of the North Cascades, WA by Siana Wong( )

2 editions published in 2013 in English and held by 2 WorldCat member libraries worldwide

The objective of my project was to describe phytoplankton ecology in high-elevation lakes of the North Cascades, WA. I conducted my field study using a small-scale ecosystem approach encompassing four lakes in the same watershed near Mt. Baker. I used exploratory data analyses to identify spatial and seasonal patterns in phytoplankton and water chemistry. Chlorophyll-a levels were less than 2.5 [mu]g/L, and total nitrogen and phosphorus levels were below 198 and 15.9 [mu]g/L, respectively, indicating the low-production and nutrient-poor nature of these lakes. Chlorophyll-a was weakly correlated with total nitrogen (Kendall's tau = 0.25, p <0.05) but was not correlated with most other water chemistry variables (p> 0.05). In the phytoplankton dataset, 88 unique taxa were found in 44 lake surface samples. The dominant taxa were members of the groups Cyanobacteria and Chlorophyta. All lakes exhibited seasonal phytoplankton succession characteristic of north temperate lakes, despite the short ice-free period. Nonparametric nonmetric cluster analysis (Riffle) resulted in separation of the four lakes into two groups based on water chemistry variables and phytoplankton abundances. The first group (Picture and Highwood Lakes) was characterized by higher water temperatures and total nitrogen levels, and lower nitrate, soluble reactive phosphate, dissolved oxygen, and pH levels compared to the second group (Upper and Lower Bagley Lakes). Higher abundances of Ochrophyta, Chlorophyta, and Cyanobacteria in the first group also contributed to cluster separation. Differences in water chemistry and phytoplankton between cluster groups could be related to differences in the lakes' external physical environments, which in turn may influence the internal chemical and biological properties of the lakes. Results from this study provide baseline information and understanding relevant to larger, longer-term research and monitoring efforts in North Cascade high-elevation lakes
 
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