Graduation date: 1991

Degradation of streams in urban-rural fringe regions occurs through complex interactions between hydrological, physical, chemical and biological mechanisms of the stream environment and surrounding landscape. Biological monitoring using macroinvertebrates may capture the complex and cumulative influences of land activity on the stream environment. The Salmon River catchment in the township of Langley, British Columbia, Canada straddles urban and rural environments in the Lower Fraser Valley. To date the Salmon River catchment has been subject to several environmental surveys. Following these earlier investigations, this study quantified relationships between the stream environment and changing land activity, across multiple scales, from 1975 to 2005, using macroinvertebrates as environmental integrators. Current and historical water, sediment, and macroinvertebrate information along with land use and land-cover evaluations were used to quantify relationships between the macroinvertebrate community and land activity in the catchment. Spatial and seasonal results for specific conductivity (a total dissolved ion indicator) and NO₃⁻-N and PO₄³ (nutrient indicators) traced groundwater and overland inputs to the stream environment. Nitrate guideline exceedances occurred at groundwater-influenced sites. Elevated sediment trace metal concentrations and Zn guideline exceedances occurred mid-reach in the catchment. Peak total macroinvertebrate and sensitive taxa abundance occurred mid-reach in the catchment in 2005, while richness and proportional sensitive abundance peaks were seen at groundwater-influenced sites. The dominance of tolerant to moderately pollution tolerant taxa occurred throughout. Despite historical water quality concerns at groundwater-influenced sites, greater shifts in community composition occurred in headwaters regions. Patterns of land use and land cover changed in sensitive areas (i.e. above aquifer and in the headwaters). A greater number of correlations between land activity and macroinvertebrate measures occurred at streams sites with 100 m buffers. The abundance of sensitive taxa positively correlated with the amount of agricultural land use, while rarefaction declined. Several Macroinvertebrate functional feeding groups correlated positively to forest cover, while sensitive taxa abundance and Zn concentrations declined. Results suggest continued water quality and sediment trace metal concerns, while macroinvertebrate results point to nutrient enrichment and greater historical variability in headwaters regions. Agricultural activity appears to have a stronger influence on aspects of the stream environment despite the presence of urban-rural land activity.

Degradation of streams in urban-rural fringe regions occurs through complex interactions between hydrological, physical, chemical and biological mechanisms of the stream environment and surrounding landscape. Biological monitoring using macroinvertebrates may capture the complex and cumulative influences of land activity on the stream environment. The Salmon River catchment in the township of Langley, British Columbia, Canada straddles urban and rural environments in the Lower Fraser Valley. To date the Salmon River catchment has been subject to several environmental surveys. Following these earlier investigations, this study quantified relationships between the stream environment and changing land activity, across multiple scales, from 1975 to 2005, using macroinvertebrates as environmental integrators. Current and historical water, sediment, and macroinvertebrate information along with land use and land-cover evaluations were used to quantify relationships between the macroinvertebrate community and land activity in the catchment. Spatial and seasonal results for specific conductivity (a total dissolved ion indicator) and NO₃⁻-N and PO₄³ (nutrient indicators) traced groundwater and overland inputs to the stream environment. Nitrate guideline exceedances occurred at groundwater-influenced sites. Elevated sediment trace metal concentrations and Zn guideline exceedances occurred mid-reach in the catchment. Peak total macroinvertebrate and sensitive taxa abundance occurred mid-reach in the catchment in 2005, while richness and proportional sensitive abundance peaks were seen at groundwater-influenced sites. The dominance of tolerant to moderately pollution tolerant taxa occurred throughout. Despite historical water quality concerns at groundwater-influenced sites, greater shifts in community composition occurred in headwaters regions. Patterns of land use and land cover changed in sensitive areas (i.e. above aquifer and in the headwaters). A greater number of correlations between land activity and macroinvertebrate measures occurred at streams sites with 100 m buffers. The abundance of sensitive taxa positively correlated with the amount of agricultural land use, while rarefaction declined. Several Macroinvertebrate functional feeding groups correlated positively to forest cover, while sensitive taxa abundance and Zn concentrations declined. Results suggest continued water quality and sediment trace metal concerns, while macroinvertebrate results point to nutrient enrichment and greater historical variability in headwaters regions. Agricultural activity appears to have a stronger influence on aspects of the stream environment despite the presence of urban-rural land activity.

Degradation of streams in urban-rural fringe regions occurs through complex interactions between hydrological, physical, chemical and biological mechanisms of the stream environment and surrounding landscape. Biological monitoring using macroinvertebrates may capture the complex and cumulative influences of land activity on the stream environment. The Salmon River catchment in the township of Langley, British Columbia, Canada straddles urban and rural environments in the Lower Fraser Valley. To date the Salmon River catchment has been subject to several environmental surveys. Following these earlier investigations, this study quantified relationships between the stream environment and changing land activity, across multiple scales, from 1975 to 2005, using macroinvertebrates as environmental integrators. Current and historical water, sediment, and macroinvertebrate information along with land use and land-cover evaluations were used to quantify relationships between the macroinvertebrate community and land activity in the catchment. Spatial and seasonal results for specific conductivity (a total dissolved ion indicator) and NO₃⁻-N and PO₄³ (nutrient indicators) traced groundwater and overland inputs to the stream environment. Nitrate guideline exceedances occurred at groundwater-influenced sites. Elevated sediment trace metal concentrations and Zn guideline exceedances occurred mid-reach in the catchment. Peak total macroinvertebrate and sensitive taxa abundance occurred mid-reach in the catchment in 2005, while richness and proportional sensitive abundance peaks were seen at groundwater-influenced sites. The dominance of tolerant to moderately pollution tolerant taxa occurred throughout. Despite historical water quality concerns at groundwater-influenced sites, greater shifts in community composition occurred in headwaters regions. Patterns of land use and land cover changed in sensitive areas (i.e. above aquifer and in the headwaters). A greater number of correlations between land activity and macroinvertebrate measures occurred at streams sites with 100 m buffers. The abundance of sensitive taxa positively correlated with the amount of agricultural land use, while rarefaction declined. Several Macroinvertebrate functional feeding groups correlated positively to forest cover, while sensitive taxa abundance and Zn concentrations declined. Results suggest continued water quality and sediment trace metal concerns, while macroinvertebrate results point to nutrient enrichment and greater historical variability in headwaters regions. Agricultural activity appears to have a stronger influence on aspects of the stream environment despite the presence of urban-rural land activity. / Science, Faculty of / Resources, Environment and Sustainability (IRES), Institute for / Graduate

The primary objective of this study was to evaluate quantitatively the effects of a mixture of agricultural and non-agricultural land use practices on the chemical characteristics of the Salmon River, near Fort Langley, B.C. Present land use and geomorphic unit maps were used to determine appropriate stream sampling sites which would give an indication of the combined and separate effects of land use and geologic materials on water quality. Chemical characteristics of the Salmon River and its tributaries were monitored over a 10 month period from May 1974 until April 1975. Eighteen chemical variables were analyzed in the laboratory using Standard Methods and 5 were monitored in the field. The in situ parameters included pH, temperature, oxidation-reduction potential, specific conductance and dissolved oxygen levels. Also monitored were 7 trace metals, Cr, Cu, Fe, Mn, Ni, Pb and Zn. Atmospheric precipitation collectors were installed at the end of June 1974 and precipitation samples collected monthly from July 1974 until April 1975. Eighteen separate chemical variables were monitored at these sites using standard methods. Stream bed sediment grab samples were taken in May and again in July 1974. These_ samples were analyzed for total elemental composition as well as total nitrogen, total carbon, total sulfur, total cation exchange capacity, exchangeable cations (Ca, Mg, Na, K) and pH. The major geologic materials in the watershed were sampled in 6 sites located in undisturbed and cultivated areas on marine, glacial outwash, and alluvial materials. The monitoring of some selected chemical characteristics of the Salmon River revealed in general the mean values of pH, specific conductivity, temperature, total alkalinity, total HC03 alkalinity, total hardness (CaCO₃ equivalent), total dissolved solids, total Kjeldahl N, organic C, NO₃ -N, CI, Na, and K were consistently higher at low streamflows than at high (>750cfs) streamflows. Oxidation reduction potential and dissolved oxygen mean values were consistently higher at high flows than at low flows. The other variables measured remained relatively constant on average across all levels of streamflow. There was, however, considerable variation at specific point samples. Data derived from collection of atmospheric precipitation indicated a significant input of many chemical factors to the watershed. Bed sediment and soils chemical characteristics give a general indication of the amounts and distribution of the various chemicals potentially available for contribution to stream waters. Analysis of the results obtained in comparison with water quality standard acceptable levels revealed water quality problems with pH, temperature, phosphorus, iron, copper, and manganese. Significant statistical correlation exists between water quality variables and glaciomarine, marine and beach overlying marine or glaciomarine materials; glacial outwash materials; agricultural field crops; low density residential areas; and schools. In order to identify specific point and non-point sources more detailed information is needed on groundwater characteristics and the streamflow characteristics of tributary streams. Some general management alternatives are recommended bearing in mind that each site must be evaluated on its own merits and specific suggestions made on-site. / Land and Food Systems, Faculty of / Graduate

Approximately 16 square km of Columbia River basalt are exposed in the Salmon River area to the south and to the west of Mount Hood, Oregon. A maximum composite basalt section composed of 15 flows and totaling 461 m is exposed in discontinuous areas of outcrop.

I investigated juvenile coho salmon (Oncorhynchus kisutch) distribution and habitat utilization in an agricultural/urban watershed, the Salmon River, Langley, B.C. The results of my empirical work confirmed the importance of instream woody debris and undercut banks in coho distribution. I examined experimentally how juvenile coho select among patches that differ in foraging profitability and in cover availability. Ideal free distribution (IFD) models were used as the practical basis for hypotheses about habitat choice by coho salmon. My experiments were conducted in artificial stream channels and involved two different types of cover, instream and overhead, and two spatial scales. The two scales (patches within individual pools and pools within stream reaches) were used to detect the effect of different levels of sampling and information processing by the fish. Juvenile coho responded positively to food abundance both within and between pools, but they did not do it as predicted by the IFD model. Cover presence further deviated coho distribution from an IFD. Within pools, coho foraged in open patches away from cover, but preferred pools with cover when choosing between separate units. None of the alternative dispersion models that I considered, derived from the IFD, fully explained the observed dispersion patterns. Coho's ability to maximize food intake rate was not only affected by the physical complexity of their habitat, but also by intraspecific competition and interference. Subsequently, I investigated experimentally coho's response to food and different densities of woody debris in natural stream reaches. If food was abundant, coho favoured pools with sparse cover, which offers accessible refuge and leaves unobstructed foraging patches where prey and perhaps also predators are easy to detect. Pools with either high densities or total lack of woody debris attracted proportionately less fish. Earlier in the summer, fry were indifferent towards cover, but as they became older their association with instream woody debris increased. Experiments I conducted during winter indicated that water velocity and temperature affected juvenile coho downstream movement. The proportion of fish that tried to leave the experimental channels increased with water discharge and decreased with water temperature. Based on the results of my empirical and experimental work, and on information derived from comparative case studies, I evaluated the potential impact of agriculture and urbanization on coho salmon habitat. Activities associated with these types of land developments tend to: a) reduce stream channel complexity; b) eliminate off-channel fish habitat; c) increase both the magnitude and the frequency of peak flows; d) augment water sediment transport; e) alter riparian vegetation; and, f) degrade water quality. A multilayered management plan, aimed at increasing coho salmon production, was developed. The plan's management strategies were devised reflecting on the different spatial scales that watershed components have and on the connectivity processes that exist among them.

I investigated juvenile coho salmon (Oncorhynchus kisutch) distribution and habitat utilization in an agricultural/urban watershed, the Salmon River, Langley, B.C. The results of my empirical work confirmed the importance of instream woody debris and undercut banks in coho distribution. I examined experimentally how juvenile coho select among patches that differ in foraging profitability and in cover availability. Ideal free distribution (IFD) models were used as the practical basis for hypotheses about habitat choice by coho salmon. My experiments were conducted in artificial stream channels and involved two different types of cover, instream and overhead, and two spatial scales. The two scales (patches within individual pools and pools within stream reaches) were used to detect the effect of different levels of sampling and information processing by the fish. Juvenile coho responded positively to food abundance both within and between pools, but they did not do it as predicted by the IFD model. Cover presence further deviated coho distribution from an IFD. Within pools, coho foraged in open patches away from cover, but preferred pools with cover when choosing between separate units. None of the alternative dispersion models that I considered, derived from the IFD, fully explained the observed dispersion patterns. Coho's ability to maximize food intake rate was not only affected by the physical complexity of their habitat, but also by intraspecific competition and interference. Subsequently, I investigated experimentally coho's response to food and different densities of woody debris in natural stream reaches. If food was abundant, coho favoured pools with sparse cover, which offers accessible refuge and leaves unobstructed foraging patches where prey and perhaps also predators are easy to detect. Pools with either high densities or total lack of woody debris attracted proportionately less fish. Earlier in the summer, fry were indifferent towards cover, but as they became older their association with instream woody debris increased. Experiments I conducted during winter indicated that water velocity and temperature affected juvenile coho downstream movement. The proportion of fish that tried to leave the experimental channels increased with water discharge and decreased with water temperature. Based on the results of my empirical and experimental work, and on information derived from comparative case studies, I evaluated the potential impact of agriculture and urbanization on coho salmon habitat. Activities associated with these types of land developments tend to: a) reduce stream channel complexity; b) eliminate off-channel fish habitat; c) increase both the magnitude and the frequency of peak flows; d) augment water sediment transport; e) alter riparian vegetation; and, f) degrade water quality. A multilayered management plan, aimed at increasing coho salmon production, was developed. The plan's management strategies were devised reflecting on the different spatial scales that watershed components have and on the connectivity processes that exist among them. / Science, Faculty of / Resources, Environment and Sustainability (IRES), Institute for / Graduate

Thesis advisor: Seth C. Kruckenberg / The Potters Pond migmatite domain (PPMD) is a heterogeneous zone of migmatites located ~10 km southwest of Cascade, Idaho within the western Idaho shear zone (WISZ). The PPMD is the only known exposure of migmatites within the WISZ over its ~300 km length, occurring where the shear zone orientation changes from 020° south to 000° north of the migmatite domain. Structural mapping within the PPMD has identified multiple generations of migmatite with varied structural fabrics. Leucosome layers were sampled from distinct migmatite localities and morphologies (e.g., metatexite, diatexite) to determine the timing and duration of partial melting in the PPMD. U-Pb age determinations of zircon by means of LA-ICP-MS document two periods of protracted migmatite crystallization during the Early and Late Cretaceous. Early Cretaceous (ca. 145 to 128 Ma) migmatite crystallization ages are coeval with the collision and suturing of oceanic terranes of the Blue Mountains province with North America, and the formation of the Salmon River suture zone (SRSZ). Migmatite crystallization ages from ca. 104 to 90 Ma are associated with Late Cretaceous dextral transpression in the WISZ. Field observations and geochronology of cross cutting leucosome relationships are interpreted to record deep crustal deformation and anatexis associated with formation of the SRSZ, subsequently overprinted by solid-state deformation and renewed anatexis during the evolution of the WISZ. These data are the first direct evidence of the synmetamorphic fabric related to the SRSZ east of the initial Sr 0.706 isopleth, and that the WISZ is a temporally distinct overprinting structure. / Thesis (MS) — Boston College, 2016. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Earth and Environmental Sciences.

The Salmon River Watershed, Langley, B.C., is on the urban-rural fringe of the Greater Vancouver Regional District. A major aquifer within the Salmon River Watershed provides rural residents with drinking water and maintains stream flow during the summer. The highly mixed land use activities in the watershed, consisting of residential development, commercial agriculture and hobby farming, are resulting in non-point source nitrogen pollution of stream and groundwater. The purpose of this study was to determine how the type, intensity and changes in land use activities have affected water quality. Indicators such as nitrate-N, ammonia-N, orthophosphate, and faecal coliforms and streptococci were used to characterize water quality. Animal unit and septic system densities and nitrogen loading were used as land use indicators. Land use/water quality relationships were analyzed with a Geographic Information System (GIS). The Salmon River and its tributaries are relatively healthy. Most of the water quality indicators met the appropriate criteria for drinking water and aquatic life. Nitrate-N concentrations and microbial counts, however, have been and continue to be a concern. While nitrate-N was below the maximum drinking water quality criterion of 10 mg-N L'1 at all stations there are localized areas where nitrate-N concentrations are above background and reaching levels of concern (5 mg-N L"1). The highest nitrate-N concentrations were measured during low-flow conditions. This suggests that the nitrogen-polluted groundwater is affecting the stream during the summer. In contrast, faecal coliforms and streptocci counts were higher during high-flow conditions suggesting runoff from agricultural fields on which manure is spread in the late fall. More than 3,200 septic systems have been installed in the Salmon River Watershed between 1930 and 1994, a large number of which are located on the Hopington Aquifer. The pattern of increasing septic system densities closely matched the increase in streamwater nitrate-N from up to downstream in both the Salmon River mainstem and Coghlan Creek upstream of their confluence. Agricultural activities are concentrated on large commercial operations. However, hobby farms are becoming a more important component of the agricultural sector in the urban-rural fringe environment. There has been an overall decrease in animal numbers, mostly due to fewer cattle, poultry and pigs between 1986 and 1991. In contrast, horses and sheep, often associated with small farms, increased in number over the same time period. Animal unit densities increased from up to downstream in the Salmon River mainstem to its confluence with Coghlan Creek as does the streamwater nitrate-N concentration. In the Coghlan, however, animal unit densities did not vary, yet the nitrate-N values in this section of the stream increased the most. These results suggest that residential and agricultural uses are both sources of nitrogen in the Salmon mainstem, while septic systems are the primary source in Coghlan Creek. A nitrogen mass balance was used to quantify the sources (manure, fertilizers, the atmosphere and septic systems) and sinks (crop uptake, management losses, dentrification) of nitrogen in the watershed in order to determine the amount of surplus nitrogen being applied. The contribution of septic systems accounted for about 20 % of the surplus loading in the watershed, while large farms contributed about 68 % and small farms 12 % of the surplus loading. There is a poor linear relationship between high nitrate-N values in the stream and corresponding spatial inputs of nitrogen from manure, fertilizers and septic systems. This is due to the highly variable surficial geology, the complexity of groundwater hydrology and the spatial lag between areas of high nitrogen surplus applications and water quality sampling stations. The area near the Salmon River-Coghlan Creek confluence is the most affected section of streams in the watershed and should be used as the key site to monitor environmental quality in the watershed.