This thesis focuses on creating effective signage for the Oregon State University College of Forestry Research Forests (OSU Research Forests). The OSU Research Forests are a unique setting because they offer space for research, class field trips, active timber harvest, and public recreation. The public interface requires the management at...
Ligand activation of the aryl hydrocarbon (AHR) has profound effects upon the immunological status of the gastrointestinal tract, establishing and maintaining signaling networks, which facilitate host-microbe homeostasis at the mucosal interface. However, the identity of the ligand(s) responsible for such AHR-mediated activation within the gut remains to be firmly established....
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microbiota-derived indoles’
TroyD. Hubbard, Iain A. Murray, William H. Bisson, Tejas S. Lahoti, Krishne
Ligand activation of the aryl hydrocarbon (AHR) has profound effects upon the immunological status of the gastrointestinal tract, establishing and maintaining signaling networks, which facilitate host-microbe homeostasis at the mucosal interface. However, the identity of the ligand(s) responsible for such AHR-mediated activation within the gut remains to be firmly established....
Full Text:
indoles
Hubbard, T. D., Murray, I. A., Bisson, W. H., Lahoti, T. S., Gowda, K., Amin, S.
G
Data science is a rapidly growing industry permeating throughout every aspect of society. Everything collects data these days, and people use this data to find meaningful patterns leading to benefits ranging from more intuitive marketing to better cancer detection. However, increased data collection also leads to increased complexity, and data...
Have you ever wondered what it would be like to live in a foreign country? You perhaps
will experience a roller coaster of emotions in what is termed “culture shock.” This
thesis will investigate the theory of culture shock and explore cultural dimensions that
affect it. These theories will be...
In recent years, participation in outdoor recreation has increased, with nearly half of Americans partaking annually (Thomsen, Powell, & Monz, 2018). The goal of recreation management is to provide diverse opportunities for leisure services through preservation of parks, open space, recreational facilities, and programs for park visitors. Management activities can...
In recent years, participation in outdoor recreation has increased, with nearly half of Americans partaking annually (Thomsen, Powell, & Monz, 2018). The goal of recreation management is to provide diverse opportunities for leisure services through preservation of parks, open space, recreational facilities, and programs for park visitors. Management activities can...
America for the past few decades, yet participation has continued to be dominated by White, upper-class individuals. These similar disparities exist in general outdoor recreation participation, with individuals from race and/or ethnic minority groups participating in outdoor recreation activities less than Whites. Research in the leisure field has revealed that...
Towns in the U.S. west are increasing in population and becoming more desirable places to live. This increase in population and tourism has led to increased pressure on public lands. State trust land is a unique land type amongst the matrix of public lands in Montana. It has a mandate...
Wilderness character monitoring (WCM) is an interagency strategy created in 2008 in collaboration between the four federal land management agencies that manage designated wilderness (Forest Service, National Park Service, Fish and Wildlife Service and Bureau of Land Management) and other contributors (Landres et al. 2008a). The reports created from this...
Wetlands are productive ecosystems providing many ecosystem services. Many regulatory agencies recognize the need to protect and preserve wetlands. However, some impacts may be unavoidable. Under those circumstances, compensatory wetland mitigation may be necessary to offset adverse impacts to wetlands. The U.S. Army Corps of Engineers and the New York...
The waterborne, myxozoan parasite Ceratonova shasta is endemic to the Pacific Northwest and can be lethal to its secondary salmonid host, including the culturally, economically, and recreationally important spring Chinook salmon (Oncorhynchus tshawytscha) of the Deschutes River, OR. Previously described genotypes of C. shasta exhibit specificity with their salmonid hosts....
The antibiotics, streptomycin sulfate and oxytetracycline, are used widely for fire blight suppression in the Pacific Northwest region of the United States. The efficacy of streptomycin, however, is compromised by widespread streptomycin-resistance in E. amylovora populations, and oxytetracycline is only partially effective. Consequently, for several years, the aminoglycoside antibiotic, kasugamycin...
In this thesis, we present semantic equivalence rules for an extension of the choice calculus and sound operations for an implementation of variational lists. The choice calculus is a calculus for describing variation and the formula choice calculus is an extension with formulas. We prove semantic equivalence rules for the...
The overall purpose of this research is to assess the Oregon public's capacity to address water resources disturbances through civil society. According to scientists and resource managers, Oregon's water resources are over taxed and at risk, with future projections placing additional stress from climate change and population growth. Oregon's 2009...
The goal of this analysis is to use the social construction framework to determine 1) whether the Oregon Drug Take Back Program stakeholder group can design a public policy that will ultimately reduce water contamination from the improper disposal of unused pharmaceuticals from the general public, and 2) use the...
Ligand activation of the aryl hydrocarbon (AHR) has profound effects upon the immunological status of the gastrointestinal tract, establishing and maintaining signaling networks, which facilitate host-microbe homeostasis at the mucosal interface. However, the identity of the ligand(s) responsible for such AHR-mediated activation within the gut remains to be firmly established....
Lead zirconate titanate (PZT) is the dominant ferroelectric material in the market due to its excellent piezoelectric properties, relatively high Curie transition temperature (T[subscript C]), low cost, etc. However, because of emerging applications with requirements for high temperature (T[subscript C] > 400 °C) ferroelectrics, researchers are increasingly looking at alternative...
Setaria lutescens (yellow foxtail) plants, grown from five seed
sources were compared in California. Seed sources were: Connecticut,
Iowa, Massachusetts, Pennsylvania and California. Morphological
and physiological differences between biotypes include: plant
size, growth habit, time required to mature and reproductive capa
city. Most significant is the prostrate habit of the...
Federally designated wilderness areas in the United States are uniquely required to provide opportunities for particular types of recreational experiences. According to the Wilderness Act of 1964, the law that governs the management of designated wilderness in the U.S., wilderness areas are to provide “outstanding opportunities for solitude or a...
Climate change is increasing the severity of pest and pathogen infestations affecting forests. Resulting shifts in disturbance patterns can have substantial ecological, social, and economic impacts on forested ecosystems and their dependent communities. Researchers are actively investigating methods to improve tree resistance to specific pests and pathogens and enhance forest...
Forest disturbances, such as wildfires, pine beetle outbreaks, and floods are important features of many landscapes and ecosystems. Many disturbances are increasing in size, frequency, and intensity due to changing climates and land management decisions. The changing ecological and aesthetic conditions following a disturbance can lead to negative short- and...
Environmental education programs seek to foster an appreciation for the natural world while introducing students to scientific thinking. Citizen science engages non-scientists in the systematic collection and analysis of data. The Betts Forest Landscape Ecology Lab combines both goals by inviting teachers in Corvallis, Oregon, and surrounding areas to participate...
Populated and developed areas at the fringes of or intermixed with undeveloped landscapes are referred to as the Wildland Urban Interface (WUI). There are many unique benefits associated with living in the WUI that understandably attract people to move to them. However, there are also potential wildfire-related risks particular to...
Disproportionate exposure to exploitative working conditions, social marginalization, and a lack of equitable living conditions are among the many issues that migrant Latinx populations face daily in the United States. However, such issues cannot be addressed by relying solely on traditional academic research approaches without the participation and direction of...
This paper examines four community forest enterprises (CFEs) in Oaxaca, Mexico, where CFEs have been held up as a positive example of community forestry that simultaneously addresses both conservation and development goals. CFEs are community-owned businesses that manage their forests to provide income and other benefits and may be considered...
This paper identifies 51 best practices of interpretive programming in relation to the topic of climate change and applies those practices to interpretive programs delivered by Natural Lands, a Pennsylvania environmental non-profit organization, and specifically at the Glades Wildlife Refuge, one of Natural Lands’ nature preserves. The best practices are...
Zirconium press plates have been developed for the production of melamine coated particle board, using shot-peening to achieve the desired plate (and therefore coated particle board) surface texture. Service temperatures of the press plates approach 200°C. This study examined the microstructural effects of extended exposure of shot-peened zirconium to temperatures...
Motivated by the Navier-Stokes equations, which are a set of unsolved equations related to fluid motion in R^3, we explored the incompressibility condition and the Neumann boundary problem. After exploring, we noticed that using iterated Riesz transforms of the boundary data could be used to get information about the velocity...
The increasing complexity and connectedness of energy networks has opened pathways for new forms of collaboration with energy consumers. Despite the emergence of the smart grid an array of policy options like demand-side management (DSM), many families continue to disregard daily household energy consumption, particularly during peak-use times of day....
Each community of scientists brings with it a set of values. Many of the urgent problems facing our planet require interdisciplinary science teams, but these teams often hold values that conflict. The Toolbox Dialogue Initiative (TDI) offers templates and guidance designed to help interdisciplinary teams of scientists recognize and address...
Few studies examine whether public attitudes toward forest management practices differ between public and private forests, with virtually no recent studies examining these differences in the Pacific Northwest, despite the coexistence of millions of acres of both public and private forest lands. Knowing whether public attitudes differ between public and...
The accumulation of fuels in fire prone landscapes, and changing climatic conditions, have resulted in increasingly volatile fire behaviors. As a result, social and operational risk, management expenditures, and budgetary requirements for responsible agencies are increasing. The United States Forest Service (USFS) manages 193 million acres across the United States...
This report assesses how current management actions are adhering to the original mandate set by the Wilderness Act of 1964 by monitoring the five qualities of Wilderness character (untrammeled, natural, undeveloped, opportunities for solitude/unconfined recreation, and other features of value) as they pertain to this specific Wilderness area.
Many studies have shown that dairies consistently overfeed nutrients such as phosphorus (P) and potassium (K). This practice is expensive and potentially damaging to the environment and to animal health. This publication suggests ways to improve feed management and thus avoid overfeeding P and K. Proper ration balancing is good...
Published September 2002. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
"This 2-year project has been helpful in characterizing nonstructural carbohydrates in cool-season grasses. We have learned a lot about the normal fluctuations seen across environments and, more specifically, variations due to genetic differences. The main conclusions are:
1. Percentages of nonstructural carbohydrate are highly variable throughout the growing season and...
Although the human health and social benefits from outdoor recreation are numerous, there is mounting evidence that outdoor recreation can negatively impact wildlife. Shorebirds are known to be especially sensitive to recreation-related disturbance because they nest and forage directly on beaches that are often used for recreation. Many studies have...
Managing wildlands to protect species and ecosystem services in response to climate change is challenging. To develop effective long-term strategies, natural resource managers need to account for the projected effects of climate change as well as the uncertainty inherent in those projections. Vegetation models are one important source of projected...
Denitrifying bioreactors are an edge-of-field treatment technology particularly well suited for nitrate removal from subsurface (tile) drainage effluent of agricultural lands. The effectiveness of a proposed denitrifying bioreactor is site-specific and depends upon the complicated interplay of field and environmental parameters controlling discharge events, nitrate concentrations, subsurface temperatures, dissolved oxygen...
Heat-related fruit damage is a common problem in the northern highbush blueberry (Vaccinium corymbosum L). This is particularly true in regions such as the northwestern United States, where summers are warm and dry, and daytime temperature regularly exceeds 32 oC. Millions of dollars of fruit damage are reported in blueberries...
Species selection is a complex process that forage producers and land managers face. Accurate tools and educational materials are needed to help make the decision process easier. Crop simulation models are one tool that could be utilized to predict yield and potential financial return of various species. Two crop simulation...
Forest management is an important mechanism that provides social, ecological, and economic benefits to the community. On public lands, management is often initiated for multi-use objectives. However, both history and research have proven that the level of acceptance for harvesting on public lands varies both temporally and spatially. Public perceptions...
Natural events such as wildfires, floods, and storms can significantly alter the short-term structure and functioning of natural systems. Recreation in wilderness areas is one instance in which individuals are directly exposed to post-disturbance landscapes. Consequently, public land managers may be faced with a different set of challenges stemming from...
In the search for better methods of agricultural management,
considerable attention has been turned to the
corporation as a useful form of business organization.
Certain farmers and ranchers can simplify their financial
planning and management by using the corporate form.
This is particularly so in "estate management," the accumulating,
maintaining,...
Keeping track of nutrient levels in dairy pastures has become an important part of farm management plans. The current recommendation is to fertilize pastures at a level to replace, in equal measure, the nutrients removed through grazing or cutting each year. The Confined Animal Feeding Operations Program (CAFO) run by...
This publication covers how pasture grows, understanding grazing systems, and forage quality. It also covers advanced tools for managing high-intensity grazing systems, such as the feed wedge (also called pasture wedge or grazing wedge).
Winter climate is expected to change under future climate scenarios, yet the majority of winter ecology research is focused in cold-climate ecosystems. In many temperate systems, it is unclear how winter climate relates to biotic responses during the growing season. The objective of this study was to examine how winter...
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Zak r. ratajcZak,2 troy w. ocheLtree,3 katya a. hafich,4 aMber c. churchiLL,4,5
Sarah j. k. frey,6
We tested the potential of a selective flatfish trawl to reduce bycatch of slope rockfish in the upper continental slope bottom-trawl fishery (250–500 m) on the U.S. West Coast. The trawl we tested differed from typical slope trawls in that it was a low-rise, two-seam trawl with a severely cut...
Lead-free Bi(Mg₁/₂Ti₁/₂)O₃-(Bi₁/₂K₁/₂)TiO₃-(Bi₁/₂Na₁/₂)TiO₃ (BMT-BKT-BNT) ceramics have
been shown to exhibit large electromechanical strains under high electric fields along with
negligible fatigue under strong electric fields. To investigate the role of point defects on the
fatigue characteristics, the composition 5BMT-40BKT-55BNT was doped to incorporate acceptor and
donor defects on the A and...
The effects of anomalous oceanographic conditions on growth, abundance, spawn-date distributions, and diet of early-juvenile Pacific hake Merluccius productus were examined in nursery grounds off the coast of central California, USA. Spring collections from 2 consecutive years of El Nino conditions, 1997 and 1998, 1 year of La Nina conditions,...
Freshwater discharge from large rivers into the coastal ocean creates tidally-driven frontal systems
known to enhance mixing, primary production, and secondary production. Many authors suggest that
tidal plume fronts increase energy flow to fish-eating predators by attracting planktivorous fishes to feed
on plankton aggregated by the fronts. However, few studies...
The Walla Walla Basin, in Eastern Oregon and Washington, USA, faces challenges in sustaining an agricultural water supply while maintaining sufficient flow in the Walla Walla River for endangered fish populations. Minimum summer river flow of 0.71 m³/s is required, forcing irrigators to substitute groundwater from a declining aquifer for...
Recently, an interest in supplementation of vitamin D to improve aspects of health, especially in human fertility, has emerged. However, supplementation of Vitamin D above the minimum required levels to prevent deficiency has yet to be explored in cattle despite evidence for vitamin D receptors in reproductive tissues. The objective...
The knowledge about the intensive agricultural irrigation is very limited, but the use of irrigation is rapidly increasing. As an outcome, the sympathetic ecosystem is accepting modern irrigation that will play an essential function in the present and future for agricultural products. My dissertation will display the modification for investigation...
Meditation research in recent decades has disproportionately focused on the Buddhist derived practice of “mindfulness” meditation while leaving most other Buddhist meditation practices unstudied. The current study seeks to remedy this homogeneity through the adaptation of a novel meditation practice used in Tibetan Buddhism to affect motivation. We explored traditional...
Previous observations suggest that females utilize a more erect initial landing posture than males with sex differences in landing posture possibly related to sex-specific energy absorption (EA) strategies. However, sex-specific EA strategies have only been observed when accompanied by sex differences in initial landing posture. This study: 1) investigated the...
High-quality forages, such as alfalfa and grasses, are important for efficient milk production from dairy cows. Forages provide the effective fiber that is critical for good health and longevity. Inadequate
effective fiber in the cow’s diet is one reason for acidosis and milk fat
depression. Historically, when forage quality changed,...
The need for miniaturization without compromising cost and performance continues to motivate research in advanced capacitor devices. In this report, multilayer ceramic capacitors based on relaxor BaTiO₃-Bi(Zn₁/₂Ti₁/₂)O₃ (BT-BZT) were fabricated and characterized. In bulk ceramic embodiments, BT-BZT has been shown to exhibit relative permittivities greater than 1000, high resistivities (ρ > 1...
The genus Lopidea Uhler is revised for America north of
Mexico. The relationship of Lopidea to other orthotyline
genera is discussed and it is proposed that the genus
Ilnacora Reuter is the sister group of Lopidea.
Forty-eight species of Lopidea are recognized in North
America, one of which is described...
Recent mandates in the United States require federal agencies to incorporate climate change science into land management planning efforts. These mandates target possible adaptation and mitigation strategies. However, the degree to which climate change is actively being considered in agency planning and management decisions is largely unknown. We explored the...
Silage corn makes excellent feed for dairy cattle because of its high dry-matter yield, energy content, and palatability, especially when mixed with other feed. Also, it does not accumulate potassium as do many
cool-season grass species. Nitrogen (N) is the most yield-limiting nutrient for silage corn production. Most dairies in...
Bird scaring lines (BSLs) protect longline fishing gear from seabird attacks, save bait, reduce incidental seabird mortality and are the most commonly prescribed seabird bycatch mitigation measure worldwide. We collaborated with fishermen to assess the efficacy of applying BSL regulations from the demersal longline sablefish fishery in Alaska to a...
Interest is expanding for the potential role of estuaries, particularly seagrass and salt marsh habitats, to sequester carbon, mitigate ocean acidification, and support abundant fisheries. The important functions of estuaries are part of a broader set of ecosystem services, or benefits to humans, which are regulated by ocean and watershed...
Winter climate is expected to change under future climate scenarios, yet the majority of winter ecology research is focused in cold-climate ecosystems. In many temperate systems, it is unclear how winter climate relates to biotic responses during the growing season. The objective of this study was to examine how winter...
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Laura M. Ladwig, Zak R. Ratajczak, Troy W. Ocheltree
Winter climate is expected to change under future climate scenarios, yet the majority of winter ecology research is focused in cold-climate ecosystems. In many temperate systems, it is unclear how winter climate relates to biotic responses during the growing season. The objective of this study was to examine how winter...
Ecosystem nitrogen (N) supply strongly influences the availability and cycling of other essential nutrients in temperate forests, especially calcium (Ca). Short-term additions of N that exceed ecosystem demands often increase dissolved nitrate fluxes and decrease soil pH, which can stimulate soil Ca loss. However, the long-term effects of high N...
Mechanical design is often based on formal methodologies such as Quality Function Deployment. Techniques to quantitatively account for attractability, sensory perception, and affective design have been successfully incorporated into these methods and are receiving growing acceptance across many industries. Although the adoption of these methods marks a large improvement for...
Field experiments were conducted with cauliflower (Brassica oleracea var.
botrytis cv. Snowball Y ) to determine crop development, yield, quality and
maturity response to various seasonal water levels, and to specific water stress
timing in relation to curd initiation. The effects of nitrogen rate, timing, and
source and the application...
The p-type semiconductor Cu₃PSe₄ has recently been established to have a direct band gap of 1.4 eV and an optical absorption spectrum similar to GaAs [Foster et al., Appl. Phys. Lett. 99, 181903 (2011)], suggesting a possible application as a solar photovoltaic absorber. Here we calculate the thermodynamic stability, defect...
Interdisciplinary research efforts to integrate the ecological aspects of water with its physical and societal roles have a long history as well as some interesting new developments. Small, paired, experimental watersheds, with their long-term monitoring systems for data collection and their integrated ecosystem approach to analysis, have been at the...
Weed resistance is usually diagnosed after a weed control practice has lost
efficacy and weed populations begin to increase rapidly. Prediction and validation in
the field at a very early stage of resistance development is a promising method for
preventing an uncontrollable problem. Pattern-thinking helped individuals connect their
experience of...
Cultural practices in snap bean production were evaluated at the Oregon State University Vegetable Research Farm Corvallis, Oregon. In addition, decision-making in snap bean production was assessed on five farms in the Coburg-Junction City-Harrisburg regions of the Willamette Valley, Oregon. A field experiment with cover crop and tillage techniques was...
A study was conducted to determine the quantity and character
of substances leached from logs floating in water, and the rate of
leaching of these substances. The species of wood studied were Douglas
fir and ponderosa pine. The research was carried out in a controlled
laboratory environment with log sections...
A study was conducted to determine the chemical nature and
the biological treatability of log pond water. Various analyses including
total solids, volatile solids, suspended solids, dissolved
oxygen, pH, COD, BOD₅, BOD₂₀, total Kjeldahl nitrogen, nitrate
nitrogen, phosphate, and PBI were performed on water samples
from each of the four...
Chemicals are being sought that can control weeds in lettuce
under different environmental conditions, soil types and weed populations.
The extensive or repeated use of a herbicide may lead to important
changes in the weed population which call for new materials
that can take care of the modified situation.
In...
Ecological communities are connected in space and time through the transfer of energy, materials, and organisms, together known as ecological subsidies. These ecological subsidies can have substantial effects on community structure, function, and services, especially when the connections are between communities with contrasting productivity. At the ocean-land interface, low productivity...
As recreation and tourism visitation increases and government budgets decrease, public
land management agencies are using private commercial operators as an alternative
source of offering products and services. Changes and trends in commercial outdoor
recreation and tourism such as a large scale increase in the number of visitors can affect...
:
_____________________________________________________________________
Mark D. Needham
As recreation and tourism visitation increases and government budgets
This study involved the use of the two-choice preference test to determine the taste reactions of buck and doe Columbian black-tailed deer (Odocoileus hemionus columbianus) to ascending concentrations of water extracts of Douglas fir, red alder, cascara, western hemlock and bitterbrush; to an ethanol extract of Douglas fir, and to...
Low-permeability geologic units may offer significant chemical and hydraulic protection of adjacent aquifers, and are important for managing groundwater quality, especially in areas with significant non-point source contamination. Nitrate in the Willamette Valley is attenuated across the Willamette Silt, a semi-confining unit overlying a regionally important aquifer. To quantify the...
Fifty-seven stranded marine mammals representing seven species
were examined over a period of three years. The primary cause of
death along with contributing factors, incidental pathology and
parasites is reported for each animal examined.
Gunshot wounds directly or indirectly caused the death of 14
of 44 seals and sea lions...
The subject of this thesis is an evaluation of a louver facility
in the Lemhi River, Idaho. The louver facility was designed to guide
juvenile chinook salmon and steelhead trout into a trap in order to
sample downstream migrant populations. The study was designed to
determine: (1) if the catch...
Connecting with nature is associated with social, physical, and emotional benefits such as stress relief, improved physical health, and lower crime. Parks and other natural areas offer spaces in which to connect with nature and reap these and other benefits (e.g., family bonding, social events, learning). Despite increasing populations of...
This study investigated the relationships among the individual’s chronological age, personality, perceived social support, appearance schema, appearance appraisal and the resultant coping strategies to overcome body dissatisfaction. Thirty four hypotheses were developed to meet the objectives of this study. The objectives were achieved by conducting two studies. Each of the...
A series of log storage experiments were conducted to determine
whether leachates derived from water storage of logs are acutely
toxic to fish. Log segments approximately 18 inches long and 16 inches
in diameter were stored in tanks and held submerged for a period of
7 days. The holding water...
Hydrologic processes within mineral flat wetlands, along with their
connections to groundwater and downstream surface water in lowland agricultural
catchments are poorly understood, particularly under different land uses. In the three
field studies included in this thesis, we examined infiltration, wetland hydroperiod,
groundwater recharge dynamics, surface runoff generation, and water...
Persistent reading difficulties are prevalent in U.S. schools and can lead to lower student performance across all subjects as well as distress, anxiety, and depression. In 2022, only 32% of fourth graders in the United States tested as proficient in reading. While there are many factors which affect reading progress...
A spectrometer, here denoted a Simple, Low-power, Inexpensive. Microcontroller-based or SLIM spectrometer. was developed that exploits the small size and low cost of solid-state electronic devices. This approach results in customizable spectrometers that are considerably less expensive and smaller than traditional instrumentation. The performance of the SLIM spectrometer was evaluated...
Forest harvest practices can impact nutrient concentrations and stream temperatures, altering aquatic ecosystems. To better inform future sustainable forest resource management practices, quantifying the impact of current practices on water quality, particularly in headwater streams is important. In this study, I quantified monthly nitrate-nitrite (N) and orthophosphate (P) concentrations, 7-day...
The treatability of waters from four log ponds in Oregon by
physical and chemical treatment methods
was investigated.
Treatment processes included sand filtration, activated carbon contact and
coagulation with aluminum sulfate.
Preliminary studies were made at each log pond to determine
the homogeneity of the pond water for sampling
purposes...
Commercial fisheries are coupled human-natural systems that cross state borders and integrate private, public, academic sectors and interests. These systems integrate complicated relationships between coastal socioeconomics, resource management and environmental realms. Previous findings from West Coast-based studies have identified aging trends in commercial fisheries participation, commonly referred to as the...