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Full-Text Articles in Physical Sciences and Mathematics
Assessing The Legacy Of Large Woody Debris As Coastal Protection In Bc And Washington, Jessica Wilson
Assessing The Legacy Of Large Woody Debris As Coastal Protection In Bc And Washington, Jessica Wilson
Salish Sea Ecosystem Conference
Large Woody Debris (LWD) accumulates naturally in the coastal environment (Brennan et al., 2009; Sass, 2009) and is thought to be a vital component of a diverse coastal habitat ( Rich et al., 2014). Decreasing natural coverage of LWD (Heathfield & Walker, 2011) and increasing demand for environmentally sensitive coastal protection techniques has led to the promotion of LWD as a viable nature-based method of shoreline protection (e.g. Johannessen et al., 2014; Stewardship Centre for BC, 2016; Washington Department of Fish and Wildlife, 2016). However, there is currently no peer-reviewed literature assessing the efficacy of coastal protection using LWD. This …
Northern Kelp Crab (Pugettia Producta) Feeding Preferences - Kelp Crabs Eat Kelp, And Lots Else?, Katie Dobkowski
Northern Kelp Crab (Pugettia Producta) Feeding Preferences - Kelp Crabs Eat Kelp, And Lots Else?, Katie Dobkowski
Salish Sea Ecosystem Conference
Bull kelp (Nereocystis luetkeana) is an important source of both habitat and primary production in the Salish Sea and appears to be in decline in certain areas. Northern Kelp Crabs (Pugettia producta) are large crustacean consumers that preferentially consume N. luetkeana over other local seaweed species in laboratory feeding trials and exert some level of top-down control on kelp populations in the field. We have observed differences in kelp crab density around the Salish Sea and noted P. producta living on invasive wireweed (Sargassum muticum) as well as on kelp and in other habitats. We used a combination of laboratory …
Begin At The Beginning: Steps, Stumbles And Learnings On The Path To Understanding And Implementing Dei Practices In Regional Engo., Christianne Wilhelmson
Begin At The Beginning: Steps, Stumbles And Learnings On The Path To Understanding And Implementing Dei Practices In Regional Engo., Christianne Wilhelmson
Salish Sea Ecosystem Conference
In 2018, Georgia Strait Alliance made the decision to begin the journey of addressing the complex issue of diversity, equity and inclusion (DEI) in our organization, one that like many environmental groups in BC lacks diversity in its staff and board. We prioritized this as we recognized there is an inherent risk that our work and our organization could become irrelevant if we don’t represent the communities we claim to serve. In addition to diversity, we also needed to address the need to deepen our relationships with indigenous communities in the Georgia Strait region and reflect those relationships in our …
A Journey, Not A Destination: An Agency Approach To Incorporate Diversity, Equity, Inclusion, And Justice, Alexandra Doty
A Journey, Not A Destination: An Agency Approach To Incorporate Diversity, Equity, Inclusion, And Justice, Alexandra Doty
Salish Sea Ecosystem Conference
Puget Sound environmental recovery is a complex, wicked problem, including both ecosystem and human and cultural wellbeing. The Puget Sound Partnership (Partnership) is a small Washington State agency that serves as a backbone organization guiding Puget Sound recovery, coordinating and collaborating with hundreds of partner organizations to accelerate recovery of Puget Sound. Our partner organizations include state and federal agencies, tribes, cities, counties, non-profits, academic institutions, special purpose districts, and many others. In 2018, the Partnership began a journey to better enable and foster diversity, equity, inclusion, and justice within the agency itself, as well as within the Puget Sound …
Harbor Porpoises (Phocoena Phocoena Vomerina) Catching And Handling Large Fish On The U.S. West Coast, Katrina Maciver
Harbor Porpoises (Phocoena Phocoena Vomerina) Catching And Handling Large Fish On The U.S. West Coast, Katrina Maciver
Salish Sea Ecosystem Conference
The harbor porpoise is a cryptic species, and information on their behavior is limited. This study describes the chase and capture of large fish by harbor porpoises (Phocoena phocoena vomerina) in the Salish Sea off Fidalgo Island, Washington, which were identified as salmonid species (2017/2019). Similar large fish chase/capture events of American Shad (Alosa sapidissima) have also been documented in San Francisco, CA (2016/2017). In all capture events consistent behavior was observed: the porpoise accelerated after the fish, swimming in a circle at the same spot, diving and coming out of the water head first carrying the fish cross-wise in …
Reconstructing A Century Of Coastal Productivity And Predator Trophic Position In The Salish Sea Using Archival Harbor Seal Bone., Megan Feddern
Reconstructing A Century Of Coastal Productivity And Predator Trophic Position In The Salish Sea Using Archival Harbor Seal Bone., Megan Feddern
Salish Sea Ecosystem Conference
Following the passage of the Marine Mammal Protection Act of 1972, pinniped populations along the west coast of North America experienced exponential population increases following historic lows in the 1970's. In the Salish Sea, this increase in pinniped abundance also corresponded to large scale changes environmental condition (ie. Pacific Decadal Oscillation; PDO) and declines of prey species (forage fish, salmon), creating new challenges and tradeoffs for fisheries management in the region. The objective of this research is to understand how an abundant top predator, harbor seals, respond to bottom up forces in the system such as shifts in primary productivity …
Shifting Phenology Of An Apex/Specialist Predator Tracks Changes In Its Favored Prey, Ailene Ettinger
Shifting Phenology Of An Apex/Specialist Predator Tracks Changes In Its Favored Prey, Ailene Ettinger
Salish Sea Ecosystem Conference
Phenology, or the timing of biological activities such as migration, growth, and reproduction, can have dramatic implications for fitness; consumer phenology that is out of step with its resource phenology can cause increased mortality or reduced reproductive success. The timing of southern resident killer whale (SRKW, Orcinus orca) movements in the Salish Sea is thought to be related to seasonal migrations of their prey. In recent decades, the abundance and phenology of the favored prey of SRKWs, salmon, has shifted in many locations across the western United States. Here, we use the OrcaMaster Database to quantify seasonal variation in SRKW …
Sources, Sinks, Dispersion And Cycling Of Dissolved Polybrominated Diphenyl Ethers (Pbdes) Discharged In The Strait Of Georgia, Yuanji Sun
Salish Sea Ecosystem Conference
The temporal and spatial distribution of dissolved PBDE concentration in the Strait of Georgia (SoG) is combined with concentrations predicted from a time-dependent box model of the Salish Sea to investigate the sources, sinks, dispersion and cycling of PBDE congeners. Prominent sub-surface concentration maxima (up to ca. 400 pg/L for total PBDE) occasionally measured in the southern SoG point to the Iona Island Waste Water Treatment Plant diffusers, discharging primary-treated effluent at 72 - 106 m depth, as an important proximal point source of dissolved PBDE. The decreasing depth of concentration maximum with increasing congener bromination suggests that dissolved PBDEs …
Results From Biennial Mussel Watch Monitoring In Sinclair And Dyes Inlets, Puget Sound, Washington From 2010 To 2018, Robert Johnston
Results From Biennial Mussel Watch Monitoring In Sinclair And Dyes Inlets, Puget Sound, Washington From 2010 To 2018, Robert Johnston
Salish Sea Ecosystem Conference
As a component of a greater effort to assess the status and trends of ecological resources within Sinclair and Dyes Inlets, a monitoring network of mussel watch sites was initiated in winter of 2010 and has continued every-other-year through 2018. Twenty-five indigenous bivalve monitoring sites were sampled biennially for a total of five campaigns. Indigenous mussels (Mytilus spp.) were collected at sites located near suspected sources (industrial, wastewater, and storm water outfalls; marinas, stream mouths, and other sources) as well as sites that were representative of ambient conditions in Sinclair and Dyes Inlets, the adjoining passages, and Liberty Bay in …
Innovative Treatment Of Wood Waste Sediments Using Reactive Amendments And Dgt Passive Porewater Sulphide Testing Techniques, Daniel Berlin
Innovative Treatment Of Wood Waste Sediments Using Reactive Amendments And Dgt Passive Porewater Sulphide Testing Techniques, Daniel Berlin
Salish Sea Ecosystem Conference
Esquimalt Harbour has historically been used for log rafting, log storage and wood mill operations over the last 70 years, resulting in the accumulation of over 200 hectares of wood waste deposits. As wood waste decomposes, it creates a biological oxygen demand in sediments that can reduce or eliminate oxygenated zones. This can lead to a buildup of compounds such as sulphides and ammonia, which are toxic to benthic organisms at higher concentrations. Public Services and Procurement Canada, on behalf of the Department of National Defence, has completed studies of wood waste sediments and is currently constructing a pilot project …
Sublethal Effects Of The Sea Lice Pesticides Ivermectin And Slice® On Starry Flounder Behaviour And Physiology When Exposed To Contaminated Sediments, Daniel King
Salish Sea Ecosystem Conference
Aquaculture is an important part of Canada’s economy, and open net-pen Atlantic salmon (Salmo salar) aquaculture is a key facet of this industry. Chemotherapeutants, including anthelminthics, are often used in salmon aquaculture to prevent the loss of stock due to various pathogens. The formulation SLICE® (active ingredient: emamectin benzoate) and ivermectin (IVM) are two chemicals used in salmon aquaculture in Canada to treat and prevent sea lice infestations. SLICE® and IVM have low water solubilities and long half-lives in sediment (225 d and >100 d, respectively). Due to the persistence of these pesticides and their tendency to accumulate in marine …
Mapping Waves And Storm Surge For Coastal Resilience In The Salish Sea, Zhaoqing Yang
Mapping Waves And Storm Surge For Coastal Resilience In The Salish Sea, Zhaoqing Yang
Salish Sea Ecosystem Conference
Pacific Northwest coasts are exposed to coastal inundation as a result of storm surge and large waves induced by extreme weather events. Accurate coastal risk projections depend on detailed and accurate information on sea level rise, including waves and storm surge under extreme weather events. This paper presents a modeling study simulating the wave climate and storm surge distribution in the Salish Sea. The Salish Sea wave model is configured with the SWAN model, driven by spectral open boundary conditions from the nested regional WaveWatch3 models and sea surface winds from a 6-km resolution Weather Research and Forecasting simulation. A …
Mapping The Cysts Of Alexandrium Catenella In The Surface Sediments Of Puget Sound: A Comparison Of Microscopy And Molecular Methods For Enumeration, Cheryl Greengrove
Mapping The Cysts Of Alexandrium Catenella In The Surface Sediments Of Puget Sound: A Comparison Of Microscopy And Molecular Methods For Enumeration, Cheryl Greengrove
Salish Sea Ecosystem Conference
Preliminary results from a newly funded NOAA NCCOS MERHAB project developing new molecular methods for detecting Alexandrium catenella cyst concentrations in marine sediments will be presented. A. catenella is a dinoflagellate that produces saxitoxin, a powerful neurotoxin, that can be concentrated in filter feeding shellfish which, if ingested by humans, can lead to paralytic shellfish poisoning and potentially death. A. catenella overwinters as a cyst in the sediment and when environmental conditions are right, in the spring and summer, germinates into the water column as a vegetative cell. Previous studies have mapped the winter distribution of A. catenella cysts in …
Sediment Sourcing In Cascade Watersheds And Nearshore Dispersal Of Terrestrial Sediment And Contaminants Using Multivariate Geochemical Analysis, Renee Takesue
Salish Sea Ecosystem Conference
Coastal ecosystems require sediment inputs of sufficient quantity and quality to maintain ecological integrity. Identification of sources and processes affecting quality and nearshore dispersal of terrestrial sediment are important considerations for successful habitat restoration and resource management. Sourcing of sediment via geochemical fingerprinting is one way to explore such processes, and appears to be a promising approach in Cascade watersheds where volcanic uplands confer distinct geochemical signatures relative to glacial and marine sediment. A sediment geochemical source-to-sink study using compositional data of the fine fraction was undertaken from the Nooksack River watershed to Bellingham and Samish Bays in March 2019 …
A Comparison Of The Vulnerability Of Marine Ecosystems To Anthropogenic Stressors, Jocelyn Nelson
A Comparison Of The Vulnerability Of Marine Ecosystems To Anthropogenic Stressors, Jocelyn Nelson
Salish Sea Ecosystem Conference
Cumulative effects assessments are increasingly required for resource management, marine spatial planning, and ecosystem-based management. A key step in a cumulative effects assessment is to determine the vulnerability of ecosystem components to stressors, which can be achieved through a vulnerability assessment. However, not all studies define vulnerability in the same way, which can lead to variable and incompatible results. For example, while many cumulative impact mapping studies use expert-derived scoring based on the variables of spatial scale, frequency, trophic impact, percentage change, and recovery time (e.g., Teck et al 2010), others, such as DFO’s Ecological Risk Assessment Framework (O et …
Effects Of Shoreline Armoring On Physical Beach Characteristics In The Salish Sea, Wa, Hannah Drummond
Effects Of Shoreline Armoring On Physical Beach Characteristics In The Salish Sea, Wa, Hannah Drummond
Salish Sea Ecosystem Conference
Increasing coastal development makes it vitally important to understand the shoreline’s response to anthropogenic modifications. We compared physical beach characteristics from adjacent sections of armored and unarmored shoreline at a variety of locations in the Salish Sea in order to assess the effects of armoring on beach morphology. Ten reaches, each a minimum of 500 meters in length, were selected from locations sampled with boat-based LiDAR collected by the Washington Department of Ecology Coastal Monitoring & Analysis Program. Cross-shore profiles were generated for each reach at 10-meter intervals alongshore. On each profile, estimates of beach slope, width, and toe elevation …
Engaging High School Juniors And Seniors At The Ocean Research College Academy As Researchers In A Two Year Study Of An Estuary In The Salish Sea, Ardi Kveven
Salish Sea Ecosystem Conference
The Ocean Research College Academy, an interdisciplinary, two year program at Everett Community College, has been utilizing the Salish Sea as a classroom for the past 16 years. Through embedded localized research in an estuary, enrolled 11th and 12th grade students conduct original research on the State of Possession Sound (SOPS) Project. This project is the backbone of the first year curriculum, where 60 students work collaboratively asking questions and gathering water quality data about the local estuary. Students analyze and interpret complex datasets that include temperature, salinity, dissolved oxygen, pH, chlorophyll concentrations, and turbidity coupled with tidal influence. As …
Sea Cucumber (Apostichopus Californicus) Culture And Enhancement Opportunities., Andy Suhrbier
Sea Cucumber (Apostichopus Californicus) Culture And Enhancement Opportunities., Andy Suhrbier
Salish Sea Ecosystem Conference
Demand for giant red sea cucumbers (Apostichopus californicus) continues in Asian markets while wild harvest has declined on the west coast of North America. Multiple trials are in place in Washington state to culture this species on upland and floating structures that support other species. Co-culture of sea cucumbers has proved to be effective with mussels, black cod, sea weed and oysters. In addition, there are food resources from aquaculture that the wild population currently exploits but conceivably could utilize more efficiently. Efforts to further this utilization are in progress.
Large Woody Debris Protects Woody Plants From Browsing In Restoration Following Elwha Dam Removal., Caelan Johnson
Large Woody Debris Protects Woody Plants From Browsing In Restoration Following Elwha Dam Removal., Caelan Johnson
Salish Sea Ecosystem Conference
The increasing number of dams approaching the end of their useful lives compels a need for knowledge about how to conduct riparian restoration associated with dam removal. One of the most difficult challenges following dam removal is restoring native vegetation to drained reservoir beds, which can be impeded by ungulate browsing. Woody plant growth can be slow in dry nutrient-poor reservoir sediment, and browsing can impede forest establishment further. We evaluated the potential for large woody debris (LWD) to limit ungulate browsing on riparian trees and shrubs following dam removal in the Elwha ecosystem. We studied LWD mitigation of browsing …
A Baseline Of Seasonal Changes In The At Sea Distribution And Abundance Of Marine Birds Near Shipping Lanes Around Southern Vancouver Island., Douglas Bertram
A Baseline Of Seasonal Changes In The At Sea Distribution And Abundance Of Marine Birds Near Shipping Lanes Around Southern Vancouver Island., Douglas Bertram
Salish Sea Ecosystem Conference
Baseline information on marine distribution and abundance of marine birds and their prey populations is needed to evaluate current status in relation to threats from potential increases in tanker traffic near Southern Vancouver Island. We conducted year round (bi-trimonthly) boat-based, at-sea surveys between Sidney BC and Victoria BC from November 2015 - November 2019 to examine seasonal variation during the year and between years. Our study area includes parts of the Sidney Channel Important Bird Area, the Shoal Harbour and Victoria Harbour Migratory Bird Sanctuaries and the Chain Islets Ecological Reserve, which are all close to major shipping lanes. With …
Monitoring Coccolithophore Blooms In Hood Canal, Seth Book
Monitoring Coccolithophore Blooms In Hood Canal, Seth Book
Salish Sea Ecosystem Conference
The re-occurrence of bloom observations of coccolithophores, Emiliania huxleyi, that were seen in the Hood Canal from 2006-2008 and resurfaced in 2016-2019 have raised concerns about adverse effects on marine shellfish resources. Crab and shrimp test fishery and catch data, together with observations of intertidal clam and oyster populations have raised the alarm with the tribal community and resource managers that the blooms adversely impacts these resources. The Skokomish Tribe has been collecting oceanographic, environmental and biological data to understand the possible causes and effects of the recurring events of the coccolithophore blooms in Hood Canal. Canal-specific oceanographic data compiled …
Between Two Worlds Indigenous High School Science Program, Todd Mitchell
Between Two Worlds Indigenous High School Science Program, Todd Mitchell
Salish Sea Ecosystem Conference
Traditional Swinomish culture relies on water dependent livelihoods in the Salish Sea, centered on the Swinomish Reservation near La Conner, Washington. A common saying at Swinomish is “when the tide is out, the table is set”; Subsistence shellfish harvests are common and Swinomish people call themselves the “People of the Salmon.” Without a clear understanding of the interconnectedness of nature, and a sense of stewardship over the land, our natural resources and traditional lifeways may be threatened. Between Two Worlds is a youth education program to give Swinomish high school students a greater appreciation of the land and environment and …
Using Seasonality And Particle Tracking To Trace Intermediate Water In The Strait Of Georgia, Samuel Stevens
Using Seasonality And Particle Tracking To Trace Intermediate Water In The Strait Of Georgia, Samuel Stevens
Salish Sea Ecosystem Conference
The Strait of Georgia is a complex system of basins and waterways within the Salish Sea that receives the majority of Greater Vancouver’s wastewater via riverine input and effluent outfalls. It can be nominally divided into three constituent water masses: (1) a riverine surface layer; (2) a deep oceanic layer; and (3) an intermediate layer, composed of a mixture of the surface and deep waters. The intermediate water (IW) layer is the largest layer volumetrically and a primary component of the region’s subsurface estuarine circulation, yet a comprehensive understanding of the system has proved challenging. Here, we use two methods …
Coastal Stream And Embayment Restoration Priorities Along The Bnsf Railroad: Results And Future Action, Phil Bloch
Coastal Stream And Embayment Restoration Priorities Along The Bnsf Railroad: Results And Future Action, Phil Bloch
Salish Sea Ecosystem Conference
The railroad right-of-way is a prominent modification along the eastern shore of the Washington portion of the Salish Sea. It runs along 52 miles of the shoreline, while another 73 miles of railroad is within 200 feet of the shoreline. In many places, the railroad forms a barrier between the coastal watershed and the shoreline, preventing the delivery of water, sediment, wood, and organic matter to the nearshore. This results in ongoing degradation of the habitat quality of the nearshore environment, which is important habitat for juvenile Chinook salmon and other salmonids. Because nearshore restoration along the railroad is expensive …
Potential Climate Change Impacts And Actions To Adapt In Nearshore And Estuarine Areas Of Howe Sound/Atl’Ḵa7tsem, Jennifer Chapman
Potential Climate Change Impacts And Actions To Adapt In Nearshore And Estuarine Areas Of Howe Sound/Atl’Ḵa7tsem, Jennifer Chapman
Salish Sea Ecosystem Conference
Howe Sound/Atl’ḵa7tsem is a fjord located near Vancouver, BC with both nearshore and estuarine habitats and communities. The coastal and estuarine habitats in the fjord are highly vulnerable to impacts from climate change (e.g., sea level rise, increased storm frequency). In order to better inform local citizens and decision-makers about possible actions for climate change adaptation in these estuarine and nearshore zones, a new report on the area’s coastal health (Ocean Watch: Howe Sound/Atl’ḵa7tsem report update) will be released in 2020. This report updates the current state of coastal ocean health in Howe Sound/Atl’ḵa7tsem since an initial report was released …
Harmful Algal Species In The Central Basin Of Puget Sound: Seasonal Bloom Patterns Analyzed Via Flowcam Technology, Lyndsey Swanson
Harmful Algal Species In The Central Basin Of Puget Sound: Seasonal Bloom Patterns Analyzed Via Flowcam Technology, Lyndsey Swanson
Salish Sea Ecosystem Conference
The Central Basin of Washington State’s Puget Sound is part of the larger estuarine system known as the Salish Sea. Long-term monitoring of this basin by King County has produced a robust dataset through the year-round collection of a suite of physical, chemical, and biological parameters. A phytoplankton monitoring program was established in 2008 using traditional microscopy methods and in 2014 a particle imaging system was added to the program. Complex interplay among a number of environmental factors contribute to the distribution and magnitude of annual phytoplankton blooms within the estuary, which regularly include several species considered potentially harmful because …
Hydrodynamics And Suspended-Sediment Transport Within An Urbanized Pacific Northwest Estuarine Embayment, Daniel J. Nowacki
Hydrodynamics And Suspended-Sediment Transport Within An Urbanized Pacific Northwest Estuarine Embayment, Daniel J. Nowacki
Salish Sea Ecosystem Conference
Coastal sediment dynamics are crucial to understanding the transport and dispersal of contaminants in urbanized environments, predicting coastal resilience in the face of rising sea levels, and synthesizing integrated ecosystem responses. Here we present six months of observations collected by four bottom-mounted moorings in Bellingham Bay, Washington, USA, covering both quiescent summer periods and more energetic fall and winter conditions. Moorings that continuously sampled currents, waves, water quality, and turbidity tracked the dispersal and transport of sediment both from modern input via the Nooksack River basin and from legacy seabed sediment sources along the urbanized Bellingham waterfront. Discrete measurements of …
Microplastics Analysis And Quantification Of Benthic Sediments Of The Salish Sea, Margaret Baer
Microplastics Analysis And Quantification Of Benthic Sediments Of The Salish Sea, Margaret Baer
Salish Sea Ecosystem Conference
Plastic marine debris presence in marine ecosystems is becoming a growing issue. Microplastics are any polymer with long axes between 0.33 to 5 mm. This material is an emerging concern because they are persistent in the environment and can build up in bed sediments, potentially creating sinks in important ecosystems such as the Salish Sea. This study will focus on determining the location, abundance, and types of microplastics in Salish Sea sediments by analyzing sediment samples provided by the Washington State Department of Ecology’s Puget Sound Ecosystem Monitoring Program. This research team processed and analyzed samples from 22 stations from …
Squishy But Not Useless For Energy Balance: Energetic Value Of Gelatinous Zooplankton From The Salish Sea And Adjacent Waters, Florian Lüskow
Squishy But Not Useless For Energy Balance: Energetic Value Of Gelatinous Zooplankton From The Salish Sea And Adjacent Waters, Florian Lüskow
Salish Sea Ecosystem Conference
Despite the low energy content, the contribution of gelatinous zooplankton (GZ; medusae, siphonophores, ctenophores, pelagic tunicates, pelagic gastropods) to predator energy budgets might be much greater than traditionally assumed (trophic dead end hypothesis). Feeding on GZ does, in fact, hold several advantages for the predator, including fast digestion, low capture and handling costs, easy access during blooms. Selective feeding on the more energy-rich tissues and organs can enhance prey attractivity for predators. Results of new analytical approaches have revealed that GZ around the world’s oceans are frequently consumed by a diverse set of marine predators. Nevertheless, GZ are infrequently included …
Toxicity Of Gasoline, Diesel And Weathered Diesel Related Petroleum Hydrocarbons To Freshwater And Marine Organisms, Curtis Eickhoff
Toxicity Of Gasoline, Diesel And Weathered Diesel Related Petroleum Hydrocarbons To Freshwater And Marine Organisms, Curtis Eickhoff
Salish Sea Ecosystem Conference
The purpose of this study was to determine environmental effects-based concentrations of total petroleum hydrocarbons for assessing the impacts of fresh gasoline and fresh or weathered diesel in the freshwater and marine environments. The study was conducted by the Washington State Department of Ecology (Ecology) and Nautilus Environmental to determine the NOEC and LOEC of gasoline, diesel and weathered diesel, in addition to IC25 and IC50 endpoints, using aquatic toxicity bioassays. In separate experiments, hydrocarbons within either the diesel or gasoline range were spiked into toxicity test solutions and weathered diesel in contaminated groundwater was obtained from a well-characterised site …