South-central Washington State Research Articles

Evaluation of a practical approach for field scale moisture flow modeling in heterogeneous media at a semiarid site

AbstractA practical approach for modeling field‐scale moisture flow in a highly heterogeneous unsaturated medium is described in this study. The validity of this approach is demonstrated through comparison of the numerical simulations with field observations at a semiarid site located in southcentral Washington State. The methodology is based on upscaling the core scale hydraulic properties and combining power‐law and tensorial connectivity‐tortuosity (PA‐TCT) approaches to derive macroscopic anisotropy parameters for each hydrostratigraphic unit (HSU) identified in the field. Each heterogeneous HSU is approximated by an equivalent homogeneous medium (EHM) model for which PA‐TCT parameters are used in the flow simulations. The available field data on moisture content and matric potential are compared with steady‐state flow simulations based on the mean form of Richards' equation. While the homogenization or averaging of heterogeneities, embedded in the EHM modeling approximation, cannot capture all of the field‐scale variability, the simulated steady‐state moisture and matric potential profiles capture well the central tendency of the field data. This approach is deemed practical for assessing the fate and transport of contaminants in highly heterogeneous unsaturated media at the transport scale of hundreds of meters.

Bee diversity and abundance in perennial irrigated crops and adjacent habitats in central Washington state

Abstract Pollinators are critical to ecosystem health and agricultural productivity. Endemic bee diversity and abundance among different crops has not been extensively studied, especially among perennial crops in Washington state. The goals of this study were to characterize bee genera diversity in south central Washington state, determine the abundance and diversity of bees among crop types, and determine if farming practices influence abundance and diversity by comparing bee diversity in managed agricultural sites to adjacent unmanaged, natural sites. This study investigated bee genera diversity and abundance in blueberry fields produced under organic certification programs, conventionally produced Concord juice and wine grape vineyards, conventionally produced spearmint and peppermint fields, and conventionally produced hopyards. The majority of bees found in the study were ground-nesting. Mint fields had the highest pollinator abundance and richness. In general, there was a greater abundance, diversity, and richness of bees found in unmanaged compared with managed sites. This indicates that areas of high agricultural intensity have relatively low bee genera abundance and diversity.

Was Coccidioides a Pre-Columbian Hitchhiker to Southcentral Washington?

Coccidioides immitis, a pathogenic environmental fungus that causes Valley fever (coccidioidomycosis) primarily in the American Southwest and parts of Central and South America, has emerged over the past 12 years in the Columbia River Basin region, near the confluence with the Yakima River, in southcentral Washington state, USA. An initial autochthonous Washington human case was found in 2010, stemming from a wound derived from soil contamination during an all-terrain vehicle crash. Subsequent analysis identified multiple positive soil samples from the park where the crash occurred (near the Columbia River in Kennewick, WA), and from another riverside location several kilometers upstream from the park location. Intensified disease surveillance identified several more cases of coccidioidomycosis in the region that lacked any relevant travel history to known endemic locales. Genomic analysis of both patient and soil isolates from the Washington cases determined that all samples from the region are phylogenetically closely related. Given the genomic and the epidemiological link between case and environment, C. immitis was declared to be a newly endemic fungus in the region, spawning many questions as to the scope of its presence, the causes of its recent emergence, and what it predicts about the changing landscape of this disease. Here, we review this discovery through a paleo-epidemiological lens in the context of what is known about C. immitis biology and pathogenesis and propose a novel hypothesis for the cause of the emergence in southcentral Washington. We also try to place it in the context of our evolving understanding of this regionally specific pathogenic fungus.

Imagining the Multilayered Cultural Landscape: A Template from the Columbia Plateau of North America

Cultural landscapes encompass a diversity of manifestations of the interaction between humankind and the natural environment occurring in both space and time. In some instances where the human occupation of a specific area or region encompass a continuous and extended timeframe, successive cultural layers yield contrasting and disparate landscapes and heritage values. This “layering” of past cultural landscapes often leads to conflicting modern-day land, cultural resource management, and heritage value issues. A case study is presented from the Hanford Site in south-central Washington state, USA, where the natural landscape comprises prehistoric Native American, historic ethnographic, and historic period non-Indian evidence from over 10,000 years of occupation and use that clearly separate into several culturally and chronologically defined and overlapping cultural landscapes, which can be visualized as layered entities occurring on the same physical space.

Development of inter-lava drainage systems in LIPs: The Columbia River Flood Basalt Province (U.S.A.) as a case study

ABSTRACT Volcanism in large igneous provinces (LIPs) is understood to have had the potential to affect global environments and ecosystems, triggering mass extinctions, climate change, and ocean acidification. However, basin-scale studies sediment distribution and sedimentary-system development in LIP lava fields are sparse and often limited to localized exposure. To gain a better understanding of the controls on inter-lava sedimentology across a continental LIP, a new sedimentological data set is presented from the Miocene Columbia River Flood Basalt Province (CRBP), situated in the Columbia Basin in south-central Washington State, northeast Oregon and eastern Idaho. Based on the qualification and quantification of sedimentary facies, petrography, paleoflow, channel dimensions, and catchment size from 96 sites across the Columbia Basin, a refined model of regional and local environmental change, integrating local volcanic and tectonic evolution, is presented. Here, CRBP stratigraphy is divided into six distinctive sedimentation intervals, which allows correlation of sedimentary interbeds formed in the western part and in the eastern part of the basin. The model describes and reviews drainage-system development and discusses the control of volcanic and tectonic activity on sediment distribution in the CRBP lava field at local to basin scale. The data presented here largely support findings of previous works suggesting a highly complex interplay between sedimentary, volcanic, and tectonic evolution of the area. In addition, it elaborates on the aspects of sediment–lava interaction and indicates that individual sub-basins in the CRBP formed separated depositional settings, emphasizing the lateral complexity of inter-lava sedimentation. Importantly, this work improves our understanding of sediment–lava relationships in continental LIPs and helps in building more generic models for sediment distribution in volcanic terranes where exposure is limited or absent.

What to do with 177 giant tanks of radioactive sludge

It's a place of superlatives. Reporters have called it the most polluted place in the Western Hemisphere. It's also the location of one of the largest construction projects in the world. · At the Hanford Site in south-central Washington state, 177 giant tanks sit below the sandy soil, brimming with the radioactive remnants of 44 years of nuclear-materials production. From World War II through the Cold War, Hanford churned out plutonium for more than 60,000 nuclear weapons, including the atomic bomb that razed Nagasaki, Japan, in August 1945. The sprawling enterprise eventually contaminated the soil and groundwater and left behind 212 million liters of toxic waste-enough to fill 85 Olympic-size swimming pools. Decades after the site stopped producing plutonium, the U.S. government is still grappling with how to clean it all up. · Today the 1,500-square-kilometer site, roughly half the size of Rhode Island, is a quiet expanse of sagebrush and wispy grasses outside Richland, Wash. The underground steel-and-reinforced-concrete tanks are grouped in "farms" beneath a central plateau, while shuttered nuclear reactors stand like sentinels on the periphery. Scientists have identified some 1,800 contaminants inside the tanks, including plutonium, uranium, cesium, aluminum, iodine, and mercury. Watery liquids rest atop goop as thick as peanut butter and salt cakes resembling wet beach sand.

Direct root-zone irrigation outperforms surface drip irrigation for grape yield and crop water use efficiency while restricting root growth

Direct root-zone irrigation is a novel subsurface drip irrigation strategy for water conservation. However, a comparison with traditional irrigation methods is lacking to better define the potential advantages of direct root-zone irrigation. A two-year study was conducted to evaluate the performance of Vitis vinifera L. cv. Cabernet Sauvignon under direct root-zone irrigation and surface drip irrigation in a commercial vineyard with loamy sand soil in a semi-arid region of southcentral Washington State, USA. Plant water status, root traits, grape yield, berry morphology and composition, and crop water use efficiency were compared between irrigation methods under three irrigation rates. Compared to surface drip irrigation, direct root-zone irrigation improved grape yield by 9–12% and crop water use efficiency by 9–11% under varied climate conditions with minor effects on berry composition, which could be potentially adjusted by irrigation rate. Moreover, grapevines irrigated through direct root-zone irrigation had 48–67% and 50–54% decrease in root number, respectively, at high and moderate irrigation rates in the upper soil profile (0–60 cm) with a decrease in water stress as revealed by higher midday stem water potential. Irrigation rate was the major factor influencing berry morphology. In fact, reduced irrigation resulted in a decrease in weight, size and number of berries. We conclude that direct root-zone irrigation could be a successful tool for improving yield and crop water use efficiency, potentially encouraging deep rooting to alleviate the water stress in grapevine under seasonal drought, and offering the ability to modify berry morphology and composition by adjusting the amount of water use.

Performance of direct root-zone deficit irrigation on Vitis vinifera L. cv. Cabernet Sauvignon production and water use efficiency in semi-arid southcentral Washington

The direct root-zone irrigation system is a new technique to deliver water directly to the root zone of grapevines at specific irrigation rates and delivery depths. The response of Vitis vinifera L. cv. Cabernet Sauvignon to direct root-zone deficit irrigation was investigated in a commercial vineyard with loamy sand soil in the semi-arid lower Columbia Basin of southcentral Washington State, USA. Three irrigation rates and three delivery depths were compared for effects on grape yield and crop water use efficiency during three consecutive growing seasons. Furthermore, we investigated the influence of irrigation rate on grape quality, and used an in situ root imaging system for root phenotyping under different delivery depths for two years. Results showed that delivery depth had no significant effect on grape yield and crop water use efficiency; however, increases in delivery depth from 30 cm to 90 cm resulted in 60–70% decreased root number and 46–59% decreased root length in the upper soil profile (0–60 cm). Moderate irrigation rates (35% less water use on average) improved crop water use efficiency by 14–23% and only reducing grape yield 15–18% per individual grapevine, without sacrificing grape quality or inducing early defoliation for the first two years. Surprisingly, no significant reduction of grape yield was found in the third year, which can be attributed to cooler and wetter weather and potentially vine acclimation to the direct root-zone irrigation strategy. We conclude that direct root-zone deficit irrigation could be a convenient and efficient subsurface irrigation method to improve crop water use efficiency without reducing grape quality under seasonal drought. Future studies should compare the economic and environmental returns of direct root-zone deficit irrigation with other traditional irrigation strategies under different environmental conditions to optimize the direct root-zone deficit irrigation method.

Physical and ecological evaluation of a fish-friendly surface spillway

Spillway passage is one of the commonly accepted dam passage alternatives for downstream-migrating salmonids and other species. Fish passing in spill near the water surface may have improved chances of survival over fish that pass deeper in the water column near spillway structures. In this study, an autonomous sensor device (Sensor Fish) was deployed in 2005 to evaluate fish passage conditions through the Removable Spillway Weir (RSW) at Ice Harbor Dam on the Snake River in south-central Washington State. The Sensor Fish deployment was undertaken concurrently with a separate live fish injury and survival study. Conditions at the RSW–Spillway Chute Transition and Deflector region were found to be potentially detrimental to fish. As a result, the spillway slope and deflector radius were modified, and the efficacy of the modifications was evaluated in 2015 using Sensor Fish and a concurrent live fish study. The frequency of severe acceleration events (acceleration≥95G) during passage decreased significantly (from 51% to 35%; p-value=0.049), and collisions with structures decreased from 47% to 27% (p-value=0.015). Pressures observed in the Spillway–Deflector region and pressure rates of change decreased as well. Overall, the modifications resulted in hydraulic conditions that contributed to improved fish passage conditions and increased fish survival.

A Methodology to Evaluate Ecological Resources and Risk Using Two Case Studies at the Department of Energy's Hanford Site.

An assessment of the potential risks to ecological resources from remediation activities or other perturbations should involve a quantitative evaluation of resources on the remediation site and in the surrounding environment. We developed a risk methodology to rapidly evaluate potential impact on ecological resources for the U.S. Department of Energy's Hanford Site in southcentral Washington State. We describe the application of the risk evaluation for two case studies to illustrate its applicability. The ecological assessment involves examining previous sources of information for the site, defining different resource levels from 0 to 5. We also developed a risk rating scale from non-discernable to very high. Field assessment is the critical step to determine resource levels or to determine if current conditions are the same as previously evaluated. We provide a rapid assessment method for current ecological conditions that can be compared to previous site-specific data, or that can be used to assess resource value on other sites where ecological information is not generally available. The method is applicable to other Department of Energy's sites, where its development may involve a range of state regulators, resource trustees, Tribes and other stakeholders. Achieving consistency across Department of Energy's sites for valuation of ecological resources on remediation sites will assure Congress and the public that funds and personnel are being deployed appropriately.

Water Markets and Storage — Substitutes or Complements for Drought Risk Mitigation?

Are water storage and water markets complements or substitutes? This paper examines the conditions under which water storage for drought risk mitigation augments or attenuates water market gains from trade, and conversely, the conditions under which water markets augment or attenuate the value of additional water storage. The analysis is performed in the context of the Prior Appropriations doctrine in a fully appropriated basin. Two stylized examples based on water use at the intensive and extensive margin are provided, along with simulation results for proposed water storage projects and market development in the Yakima Basin in South-central Washington State.

Relative abundance and phenology ofDrosophilaFallén, 1815 (Diptera: Drosophilidae) species in south-central Washington State

Abstract. A monitoring program for a recently introduced vinegar fly, Drosophila suzukii Matsumura, 1931, was conducted in south-central Washington State, U.S.A. from March 2011 to November 2013. Along with D. suzukii, a complex of nine additional Drosophila Fallen, 1815 species were captured in baited traps and identified to species. The Drosophila were captured in Nalgene® and Haviland traps baited with apple cider vinegar or a sugar yeast mixture that were distributed among seven different horticultural crops or unmanaged habitats. All flies captured were identified to species and quantified for each sampling period. The species identified and quantified included D. busckii Coquillett, 1901, D. funebris Fabricius, 1787, D. hydei Sturtevant,1921, D. immigrans Sturtevant, 1921, D. melanogaster Meigen, 1830, D. simulans Sturtevant, 1919, D. obscura Fallen, 1823, D. subobscura Collin, 1936, D. subquinaria Spencer, 1942 and D. suzukii. The predominant species in 2011 were the obscura group and D. hydei. In ...

HUMAN DISTURBANCE AND THE PHYSIOLOGICAL RESPONSE OF ELK IN EASTERN WASHINGTON

Stress hormone measures have proven useful for assessing effects of human disturbance on wildlife populations. However, most studies are of short duration or limited geographic scope (i.e., without spatial replication), leading to concerns about confounding effects of biotic conditions. Previous research correlated fecal glucocorticoid metabolites (FGMs) of elk (Cervus elaphus) with human disturbance, but this factor also co-varied with seasonal climatic conditions, making it difficult to make broader inference regarding the role of human disturbance. In this study we attempted to simultaneously evaluate the effects of climatic conditions and human disturbance by comparing the year-round physiological stress response of elk to varying levels of human disturbance at three study sites in south-central Washington State. FGMs were consistently elevated throughout the year at the study site receiving the greatest amount of human disturbance. We observed support for a positive effect of precipitation and increasing temperature on FGMs at the low-disturbance site, but less support for importance of climatic variables in explaining FGMs at the high-disturbance sites - suggesting that climatic variables were likely of secondary importance compared to anthropogenic stressors in elk at those sites. Collectively, while we were unable to disentangle the effects of site- specific stressors, our findings suggest that in this environment, humans were a dominant stressor influencing FGM levels. Therefore, interpreting results of physiological studies requires that researchers account for a broad combination of biotic and abiotic stressors at a particular study location. We particularly encourage future investigators to account for the potential confounding effect of human disturbance that could override other stressors.

Beauty with benefits: butterfly conservation in Washington State, USA, wine grape vineyards

The butterfly fauna of south central Washington State, USA is characterized by shrub-steppe specialists adapted to hot, dry summers and cold winters. However, the shrub-steppe ecosystem has diminished at an alarming rate due to extensive agricultural development fostered by access to an abundant water supply from the Cascade Mountains. This has resulted in loss and fragmentation of habitat for ~50 species of butterflies which are now in decline. Viticulture is a major agricultural industry in south central Washington and has transitioned in recent years to a sustainable, low pesticide-input enterprise. Current viticultural pest management research is focused on restoration of shrub-steppe habitat and native plants to enhance and sustain beneficial arthropod populations (predators and parasitoids) for pest control. Butterfly populations were surveyed during 2012–13 in a pair of vineyards (habitat-enhanced, conventional) in each of four viticultural regions [Columbia gorge (CG), Walla Walla valley (WWV), Yakima valley (YV), Wahluke slope (WS)] in south-central Washington. The habitat-enhanced sites supported a significantly greater number of flowering plant species (mostly native) than conventional vineyard sites. Twenty nine butterfly species were recorded from the habitat-enhanced vineyards with only nine of these recorded from the conventional vineyards. Overall, there were double the number of species in habitat-enhanced vineyards [mean (±SE) 5.62 ± 0.85] compared to conventional vineyards (2.75 ± 0.75) although this was not statistically significant. A significantly greater number of species occurred in the CG and WWV habitat-enhanced vineyards (10.5 ± 0.5) compared to the conventional vineyards (3.5 ± 0.0) in these regions. Smaller numbers of butterfly species occurred in YV and WS vineyards with no significant differences between habitat-enhanced and conventional sites. Butterfly abundance was significantly greater in habitat-enhanced vineyards (20.37 ± 5.34 individuals/visit) compared to conventional vineyards (5.5 ± 0.9) with greatest differences in the CG and WWV vineyards. The pest management strategy of restoring native plants and habitats in a low pesticide-input crop like wine grapes in central Washington may have substantial benefits for butterfly abundance, diversity and conservation. Many of the flowering native perennials important in attracting and sustaining endemic biological control agents, are also larval hosts and/or nectar sources for threatened shrub-steppe butterflies.

Solidification and stabilization of silver mordenite used to control radioiodine emissions from Hanford’s Waste Treatment Plant

The United States Department of Energy is building the Hanford Waste Treatment and Immobilization Plant (WTP) in south-central Washington State to immobilize a portion of the stored high-level radioactive wastes generated by decades of producing nuclear defense materials. To comply with United States Environmental Protection Agency (EPA) and Washington State air emission regulations, the WTP is planning to use reduced silver mordenite to control releases of any volatilized waste constituent radioiodine (129I t1/2=1.7×107a). Because the EPA and Washington State have designated silver as a hazardous or dangerous waste constituent, the disposal form for the waste reduced silver mordenite must comply with their land disposal regulations. We used the mandated EPA Toxic Characteristic Leach Procedure to evaluate and qualify a disposal form for the waste reduced-silver mordenite. Our development effort resulted in a regulation-compliant disposal form which used cast American Society for Testing and Materials (ASTM) Portland Type III cement modified to include calcium iodide to solidify and stabilize the reduced-silver mordenite and control silver release to regulatory levels.

Ground beetles (Coleoptera, Carabidae) of the Hanford Nuclear Site in south-central Washington State

In this paper we report on ground beetles (Coleoptera: Carabidae) collected from the Hanford Nuclear Reservation and Hanford National Monument (together the Hanford Site), which is located in south-central Washington State. The Site is a relatively undisturbed relict of the shrub-steppe habitat present throughout much of the western Columbia Basin before the westward expansion of the United States. Species, localities, months of capture, and capture method are reported for field work conducted between 1994 and 2002. Most species were collected using pitfall traps, although other capture methods were employed. Trapping results indicate the Hanford Site supports a diverse ground beetle community, with over 90% of the 92 species captured native to North America. Four species collected during the study period are newly recorded for Washington State: Bembidion diligens Casey, Calosoma obsoletum Say, Pseudaptinus rufulus (LeConte), and Stenolophus lineola (Fabricius). Based on these data, the Site maintains a diverse ground beetle fauna and, due to its size and diversity of habitats, is an important repository of shrub-steppe biodiversity.

Slow-Rusting Resistance in Native Spearmint to Puccinia menthae.

Rust, caused by Puccinia menthae, is often a serious yield-reducing problem on native and Scotch spearmint in south-central Washington State. Rust resistant mint cultivars would reduce a dependence on fungicides for disease management; however, conventional breeding practices are not possible because commercial mint plants are sterile. Mutant Scotch and native spearmint lines induced by irradiation were evaluated for partial resistance to rust. Latent period and number of uredinia per leaf from urediniospore inoculations in the greenhouse and aecial and uredinial development in the field were quantified. Length of latent period, number of uredinia per leaf, incidence of shoots with aecia, and area under the disease progress curve (AUDPC) for uredinia development all varied significantly among lines and standard cultivars. Length of latent period was significantly longer and number of uredinia per leaf was significantly lower for native spearmint line N87-1 than for most of the other mutant lines, native spearmint, and Scotch spearmint. Line N87-1 had the lowest AUDPC values of all lines and standard cultivars for 3 years in the field. However, line N87-1 had a relatively high incidence of shoots with aecia both of two years in the field. Length of latent period was significantly and negatively correlated with AUDPC 2 of 3 years. Mean incidence of shoots with aecia was not correlated with AUDPC or with length of latent period after urediniospore infection. Rust in native spearmint in south-central Washington State could be satisfactorily managed with slow-rusting resistance when coupled with good irrigation water management and sanitation tactics that limit aecia development on early spring mint foliage.

Habitat distribution and seasonality of the northern scorpion, Paruroctonus boreus (Girard) (Scorpiones: Vaejovidae), at the Hanford Site, southcentral Washington State

Abstract The northern scorpion, Paruroctonus boreus (Girard 1854) is recorded from big sage climax, sand dune, cheatgrass dominated, and partially disturbed big sage habitats on the Hanford Nuclear Site, located in southcentral Washington State. Based on a pitfall trapping survey, the species was most commonly encountered in partially disturbed big sage habitat and rarely found in cheatgrass dominated plant communities. A total of 127 specimens were taken with the earliest collection made 20–28 March and the latest 9–24 October. Habitat occurrence on the Hanford Site is compared with comparable studies at other locations. The possible negative effect of cheatgrass invasion on scorpion occurrence is discussed.

Quantitative 3-D Elemental Mapping by LA-ICP-MS of a Basaltic Clast from the Hanford 300 Area, Washington, USA

Laser ablation with inductively coupled plasma-mass spectrometry (LA-ICP-MS) was used to measure elemental concentrations at the 100-μm scale in a 3-dimensional manner within a basaltic clast sample collected from the Hanford 300 Area in south-central Washington State, United States. A calibration method was developed to quantify the LA-ICP-MS signal response using a constant-sum mass fraction of eight major elements; the method produced reasonable concentration measurements for both major and trace elements when compared to a standard basalt sample with known concentrations. 3-Dimensional maps (stacked 2-D contour layers, each representing 2100 μm × 2100 μm) show relatively uniform concentration with depth for intrinsic elements such as Si, Na, and Sr. However, U and Cu accumulation were observed near the sample surface, consistent with the site's release history of these contaminants. U and Cu show substantial heterogeneity in their concentration distributions within horizontal slices, while the intrinsic elements are essentially uniformly distributed. From these measured U concentrations and published grain size distributions, gravel and cobbles were estimated to contain about 1% of the contaminant U, implicating the coarse fraction as a long-term release source.

European Earwig,Forficula auriculariaL. (Dermaptera: Forficulidae), at the Hanford Reach National Monument, Washington State

The European earwig, Forficula auricularia L., was surveyed using pitfall traps at 3 sites at the Hanford Reach National Monument in south central Washington State. Pitfall traps were collected weekly from April 2002 through April 2003. The earwig was consistently taken during all months of the year at a disturbed, weedy site along the Columbia River (White Bluffs Ferry site) but was rare or not collected in 2 less-disturbed shrubsteppe habitats. Highest numbers occurred during April-May, when immatures accounted for the majority of the catch; immatures reached the adult stage during mid-July, and the species is univoltine at the site. Possible reasons why earwigs have not colonized the monument's shrubsteppe habitat include the arid climate with lack of available moisture, especially for breeding purposes, and a lack of burrow sites.