Pacific Northwest United States Research Articles

Identifying blueberry germplasm that is slow to get Blueberry shock virus in the Pacific Northwest United States

Identifying blueberry germplasm that is slow to get <i>Blueberry shock virus</i> in the Pacific Northwest United States

Pacific lamprey recolonization of a Pacific Northwest river following dam removal

AbstractRecolonization of Pacific lampreys Entosphenus tridentatus into historically used freshwater habitats in the United States Pacific Northwest was evaluated in the White Salmon River basin after removal of Condit Dam. Pacific lamprey population declines are of concern, and passage barrier removal is often recommended for conservation. Condit Dam on the White Salmon River in Washington was a complete barrier to fish migrating upstream for nearly 100 years, was breached in 2011, and was removed by 2012. Distribution of larval Pacific lampreys was estimated before and after removal of Condit Dam using either backpack or deepwater electrofishing. Larval detection probabilities were calculated for the basin, and sample efforts were refined to ensure at least 80% confidence that larvae were absent when not detected. Pacific lampreys were not present upstream of Condit Dam before it was removed but were present in areas downstream of the dam. After dam removal, Pacific lamprey larvae were collected upstream of the former dam site from four reaches of the mainstem White Salmon River, indicating a recent recolonization event. Pacific lampreys were absent from the river mouth area before the dam was removed but were found in newly created habitat at the mouth after dam removal. Pacific lampreys naturally recolonized the White Salmon River basin within a few years after dam removal. Removing dams and providing passage opportunity can allow Pacific lampreys to distribute into vacant areas and may help reverse population declines.

Precipitation extremes and their relation to climatic indices in the Pacific Northwest USA

There has been focus on the influence of climate indices on precipitation extremes in the literature. Current study presents the evaluation of the precipitation-based extremes in Columbia River Basin (CRB) in the Pacific Northwest USA. We first analyzed the precipitation-based extremes using statistically (ten GCMs) and dynamically downscaled (three GCMs) past and future climate projections. Seven precipitation-based indices that help inform about the flood duration/intensity are used. These indices help in attaining first-hand information on spatial and temporal scales for different service sectors including energy, agriculture, forestry etc. Evaluation of these indices is first performed in historical period (1971–2000) followed by analysis of their relation to large scale tele-connections. Further we mapped these indices over the area to evaluate the spatial variation of past and future extremes in downscaled and observational data. The analysis shows that high values of extreme indices are clustered in either western or northern parts of the basin for historical period whereas the northern part is experiencing higher degree of change in the indices for future scenario. The focus is also on evaluating the relation of these extreme indices to climate tele-connections in historical period to understand their relationship with extremes over CRB. Various climate indices are evaluated for their relationship using Principal Component Analysis (PCA) and Singular Value Decomposition (SVD). Results indicated that, out of 13 climate tele-connections used in the study, CRB is being most affected inversely by East Pacific (EP), Western Pacific (WP), East Atlantic (EA) and North Atlaentic Oscillation (NAO).

Effects of dietary lipid and light source on steatitis in steelhead, Oncorhynchus mykiss

The primary lipid source in feeds used at Pacific salmon (Oncorhynchus spp.) and steelhead (anadromous O. mykiss) conservation hatcheries in California and the Pacific Northwest United States is marine fish oil which is characterized by high levels of long-chain polyunsaturated fatty acids (LC-PUFAs). As these fatty acids are prone to peroxidation, the high marine fish oil content of salmonid feeds is likely a contributing factor in a disease called steatitis which is an ongoing issue at some hatcheries. Dermal lesions associated with steatitis have been observed when affected fish were transferred from enclosed hatchery buildings to outdoor rearing units exposed to sunlight. Therefore, a two-factor study examining possible interactive effects of dietary lipid source and ultraviolet (UV) radiation on growth responses, histology and tissue fatty acid profiles of juvenile steelhead was conducted. For 10weeks, fish were fed diets containing canola oil (CO), fish oil (FO) or oxidized fish oil (OFO) while exposed to fluorescent or UV light. Each treatment was randomly assigned to triplicate groups of 50 fish initially weighing 1.6g/fish. The main effects of lipid and light source on growth responses and survival were not statistically significant, but percent weight gain was significantly affected by interaction of the main effects. Whole body histopathology revealed significantly higher (more severe) steatitis scores in fish fed FO or OFO compared with fish fed CO and in fish exposed to UV light compared with fish exposed to fluorescent light. Whole body lipid concentration and tissue fatty acid profile were significantly affected by lipid and light source but not their interaction. These results suggest reducing dietary LC-PUFAs and minimizing UV light exposure may reduce steatitis in steelhead.

Methods to assess between-system adaptations to climate change: Dryland wheat systems in the Pacific Northwest United States

In this paper we propose to extend methods for agricultural impact assessment to study the adaptations that agricultural producers are likely to consider in response to climate change – i.e., the use of different combinations of crop or livestock species and associated changes in management. Analysis of these kinds of adaptations, referred to here as “between-system adaptations” – requires estimates of the counterfactual productivity and cost of production for prospective systems that are not observable in the locations where they could be used. We propose two methods that we call simulation matching and propensity score matching. We apply and compare the results of these methods in a study of wheat-based systems in the U.S. Pacific Northwest. We find substantial differences between the two methods, but these differences do not appear to be systematic or associated with characteristics of the systems. We conclude that the method used for estimating the productivity of the new system introduces an element of uncertainty into adaptation analysis, in addition to the other data, model and scenario uncertainties. Further research is warranted to evaluate alternative methods for analysis of between-system adaptations and their associated uncertainties.

Economic, policy, and social trends and challenges of introducing oilseed and pulse crops into dryland wheat cropping systems

The productivity of semi-arid, cereal-based agroecosystems is inherently limited by water and nutrient availability, with water limitations expected to be exacerbated by climate change. While previous studies have identified agronomic, economic, and environmental benefits of rotating oilseed, pulse, and cover crops with cereals for mitigating the effects of increasing temperatures and water shortages, the successful integration of alternative crops into cereal based systems is contingent upon economic, social, and policy conditions. This paper analyses the historical spatial and temporal trends in crop diversification in three distinct cropping regions, including the Canadian prairies, Australian wheat belt, and the inland Pacific Northwest USA (iPNW). The first objective was to identify key sociological, economic, and policy drivers that corresponded with historical crop intensification and diversification in Canada and Australia over the last 50 years. The second objective was to identify key economic, policy, and social constraints that have historically limited intensification and diversification in the iPNW, a cereal-dominated region. In Canada and Australia, public policy played a critical role in the adoption of alternative crops through investments in research and boundary-spanning agencies, as well as extension and grower-led efforts. Policies also provided incentives for market development and risk management strategies. Grower perceptions of risk, the ability to utilize existing resources and knowledge, and access to markets were important social considerations for crop diversification. Given the competitiveness of wheat in the iPNW, the largest opportunities for diversification in the iPNW would be provided by (1) the adoption of a crop rotation approach to the economics that capture relative commodity prices, yield stability, and the effects of alternative crops on subsequent wheat performance, (2) the transition away from coupled crop insurance to income-supported, whole farm risk management, and (3) the establishment of multi-commodity groups that replace single crop commodity commissions in the interest of market-driven crop diversification.

Prediction of Canola Residue Characteristics Using Near-Infrared Spectroscopy

Little work has been done to characterize and quantify the residue traits affecting decomposition of winter and spring canola (Brassica napus L.) residue in dryland farming systems of the Pacific Northwest United States. Traditional methods of characterizing residue fiber and nutrients are time-consuming and expensive and require large quantities of chemical reagents. The goal of this research was to determine whether near-infrared spectroscopy (NIRS) could accurately predict neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL), carbon (C), and nitrogen (N) of canola stems, litter, and roots and decomposition of canola stems. Canola residue varied in decomposition, fiber, and nutrients by year, location, and type. NIRS predictions were successful for NDF and ADF in 2011 (standard error of prediction SEP&lt;2.67; R2&gt;0.95) and NDF, ADF, and N in 2012 (SEP&lt;2.38; R2&gt;0.91). Other predictions for residue fiber and nutrient characteristics were considered moderately successful. Prediction of canola residue decomposition with NIRS was useful for screening purposes. Near-infrared spectroscopy shows promise for rapidly and reproducibly predicting some canola residue fiber and nutrient traits and may be useful for estimating residue decomposition potential in dryland conservation cropping systems.

Delineating the Southwest British Columbia Bioregion for Food System Design and Planning: A Practical Approach

In light of climate change, resource depletion and environmental degradation, food system vulnera­bility, and food insecurity, the potential to address issues of food system sustainability on local and regional scales is being increasingly recognized and pursued. Bioregions, generally defined as areas that share similar topography, plant and animal life, and human culture, represent an appropriate and consistently applicable scale and framework for sustainable food system analysis, design, and planning. As such, for a southwest British Columbia (SWBC) bioregion food system design and planning project, our first task was to delineate our bioregion. We report on the process, deliberations, and practical considerations that contributed to the determination of the SWBC bioregion for subsequent study. In addition to a complex biogeographic landscape that includes mountains, a major river system and delta, and a marine ecosystem, SWBC’s multicultural and urban/suburban/rural character is further compounded by its proximity to Vancouver Island, as well as by an international border with the Pacific Northwest United States; all represented important considerations in determining the dimensions of the bioregion. Bioregional-scale food system design and planning brings to the forefront the interdependency between human economy and community and the biophysical landscape with which they interact. In this reflective essay, we share our experience in the hope that it will inform the work of other communities in effectively delineating bioregions for food system design and planning that better align human communities and their economy with their environment. We believe the methodology presented has potential for widespread adaptation.

Dietary assessment of domoic acid exposure: What can be learned from traditional methods and new applications for a technology assisted device

Three Tribal Nations in the Pacific Northwest United States comprise the members of the CoASTAL cohort. These populations may be at risk for neurobehavioral impairment, i.e., amnesic shellfish poisoning, from shellfish consumption resulting in repeated, low-level domoic acid (DA) exposure. Previous work with this cohort confirmed a high proportion of clam consumers with varying levels of potential exposure over time. Since clams are an episodically consumed food, traditional dietary records do not fully capture exposure. Frequency questionnaires can capture accumulated doses over time and this data can be used to examine dose–response relationships with periodic studies of memory and learning. However, frequency questionnaires cannot be used to assess consumption and memory response in real time. To address this shortcoming, a modified technology assisted dietary assessment (TADA) iPod application was developed to capture images of the clam meal, sourcing data, and associated memory functioning within 24h and seven days after consumption. This methodology was piloted with razor clam meals consumed by members from the CoASTAL cohort. Preliminary findings suggest that the TADA iPod application is potentially useful in collecting real-time data with respect to razor clam consumption, as well as one day and seven day memory outcome data. This technology holds promise for addressing the challenges of other HAB related dietary exposure outcome studies.

Daughters of the Drum: Decolonizing health and wellness with Native American women

In many pre-colonial tribal communities, Native American women held significant positions as keepers and teachers of health and wellness practices. Today, however, Native American women's status is often relegated to the margins in colonial society, as they are disproportionately affected by health disparities resulting from legacies of historical trauma. This study explores the decolonization of the health and wellness of Native American women in the United States Pacific Northwest. Through a culturally centered qualitative study utilizing photovoice and talking circles, several themes emerge illuminating important and nuanced aspects of resilience related to perceptions of health and wellness. Four Native American women aged 26–46, including myself, participated in the study in the summer of 2014. Utilizing the indigenist stress-coping model, interpretive coding in real time suggests that land, language, and diet are important principles of a decolonized perception of health and wellness centered on the women's experiences together as members of the drum group Daughters of the Drum.

Environmental Sentencing in the United States Pacific Northwest 2007–2011

A significant body of research suggests that environmental risks are more likely to be found in minority and low-income communities. Few studies have questioned whether communities of lower socioeconomic status may be less protected by regulatory agencies through the use of fines in instances of noncompliance. Using the Environmental Inequality Formation perspective (EIF) and data drawn from the U.S. Environmental Protection Agency’s (EPA) administrative enforcement cases within the U.S. Pacific Northwest from 2007 to 2011, this project finds that the factors primarily influencing fine severity include the type and severity of the offense. However, after controlling for other factors, fines are less severe against facilities surrounded by low-income households. This research confirms the need for scholars, policy makers, and activists to develop greater linkages between the EIF perspective and environmental sentencing by more clearly teasing out the roles that facilities, enforcement agencies, and especially communities play in these outcomes.

Community-Level Actions that Can Address Ocean Acidification

Ocean acidification has led to detectable changes in seawater chemistry around the world, which are associated with reduced growth and survival of many species. Acute ocean acidification “events” in the Pacific Northwest United States have jeopardized the $270 million, 3,200 jobs/year shellfish aquaculture industry in Washington State, and this has contributed to the state’s broad-based, legislatively driven response to ocean acidification. Even though impacts from ocean acidification have yet to be felt in many locations, states and regions are beginning to take action on the issue. In this paper, we present an array of actions that can be undertaken by communities or regions to address ocean acidification. The actions can be coupled, completed one at a time, or aligned with other environmental initiatives, and they can be tailored to the prevailing political or economic environment. We review which have been used by different U.S. states and identify common themes and popular choices. We close by suggesting combinations of conditions and clusters of activities that seem to promote rapid and sustained action. Cutting atmospheric carbon dioxide levels internationally is still the most comprehensive way to address ocean acidification, but this analysis shows that productive actions can still be taken at smaller scales to help marine resource-dependent communities adapt to existing ocean acidification and prepare for possible future impacts.

Prolonged Distress of Parents After Early Preterm Birth

ObjectiveTo examine how parents describe the distress of early preterm birth in the months and years after the infant's hospital discharge. DesignDiscourse analysis of in-depth interviews and photo elicitation. SettingHomes or cafés in the Pacific Northwest United States. ParticipantsParents of premature infants born between 24 and 30 weeks gestation (N = 10) who experienced significant distress in and out of the hospital. Parents participated in the study when their children were between 15 months and 8 years old. MethodsParticipants described dealing with prematurity, emotional distress, and parenting in individual interviews and returned for second interviews in which they further described their distress using photographs. Data were analyzed using discourse analysis. ResultsParents described preterm birth, hospitalization, and the aftermath as ongoing traumatic events. Discourses of distress included the Perfect Child, the Good Mother, and the Good Father. Parents used these discourses to reconcile the loss of an idealized birth and parenting after the birth of a premature child. Isolation and Medicalized Parenting were used to explain how parents struggled to interact within their social networks and to parent under challenging circumstances. ConclusionParticipants described their trauma and distress in ways not captured by psychiatric diagnoses such as depression and anxiety. Findings may help nurses be aware of the negative effects of preterm birth and respond to parents' emotional needs.

Rapid Quantitative Assessment of Rhizoctonia Resistance in Roots of Selected Wheat and Barley Genotypes

Rhizoctonia solani AG8, causal agent of Rhizoctonia root rot and bare patch in dryland cereal production systems of the Pacific Northwest United States and Australia, reduces yields in a wide range of crops. Disease is not consistently controlled by available management practices, so genetic resistance would be a desirable resource for growers. In this report, we describe three rapid and low-cost assays for R. solani AG8 resistance in wheat and barley, with the view of facilitating screens for genetic resistance in these hosts. The first assay uses 50-ml conical centrifuge tubes containing soil infested with R. solani AG8 on a substrate of ground oats. The second assay uses roots of 3-day-old seedlings directly coated with infested ground oats, followed by incubation in plastic dishes. The third assay, suitable for barley, uses whole infested oat kernels in 50-ml tubes. Symptoms are quantified on the bases of root fresh weight and total root length at 7 and 3 days for the tube and coating assays, respectively. Each of the assays show the same disease differential between susceptible and partially resistant wheat genotypes. The assays can be conducted in the laboratory, growth chamber, or greenhouse.

Multi-criteria evaluation of CMIP5 GCMs for climate change impact analysis

Climate change is expected to have severe impacts on global hydrological cycle along with food-water-energy nexus. Currently, there are many climate models used in predicting important climatic variables. Though there have been advances in the field, there are still many problems to be resolved related to reliability, uncertainty, and computing needs, among many others. In the present work, we have analyzed performance of 20 different global climate models (GCMs) from Climate Model Intercomparison Project Phase 5 (CMIP5) dataset over the Columbia River Basin (CRB) in the Pacific Northwest USA. We demonstrate a statistical multicriteria approach, using univariate and multivariate techniques, for selecting suitable GCMs to be used for climate change impact analysis in the region. Univariate methods includes mean, standard deviation, coefficient of variation, relative change (variability), Mann-Kendall test, and Kolmogorov-Smirnov test (KS-test); whereas multivariate methods used were principal component analysis (PCA), singular value decomposition (SVD), canonical correlation analysis (CCA), and cluster analysis. The analysis is performed on raw GCM data, i.e., before bias correction, for precipitation and temperature climatic variables for all the 20 models to capture the reliability and nature of the particular model at regional scale. The analysis is based on spatially averaged datasets of GCMs and observation for the period of 1970 to 2000. Ranking is provided to each of the GCMs based on the performance evaluated against gridded observational data on various temporal scales (daily, monthly, and seasonal). Results have provided insight into each of the methods and various statistical properties addressed by them employed in ranking GCMs. Further; evaluation was also performed for raw GCM simulations against different sets of gridded observational dataset in the area.

Breeding Bird Community Continues to Colonize Riparian Buffers Ten Years after Harvest.

Riparian ecosystems integrate aquatic and terrestrial communities and often contain unique assemblages of flora and fauna. Retention of forested buffers along riparian habitats is a commonly employed practice to reduce potential negative effects of land use on aquatic systems. However, very few studies have examined long-term population and community responses to buffers, leading to considerable uncertainty about effectiveness of this practice for achieving conservation and management outcomes. We examined short- (1–2 years) and long-term (~10 years) avian community responses (occupancy and abundance) to riparian buffer prescriptions to clearcut logging silvicultural practices in the Pacific Northwest USA. We used a Before-After-Control-Impact experimental approach and temporally replicated point counts analyzed within a Bayesian framework. Our experimental design consisted of forested control sites with no harvest, sites with relatively narrow (~13m) forested buffers on each side of the stream, and sites with wider (~30m) and more variable width unharvested buffer. Buffer treatments exhibited a 31–44% increase in mean species richness in the post-harvest years, a pattern most evident 10 years post-harvest. Post-harvest, species turnover was much higher on both treatments (63–74%) relative to the controls (29%). We did not find evidence of local extinction for any species but found strong evidence (no overlap in 95% credible intervals) for an increase in site occupancy on both Narrow (short-term: 7%; long-term 29%) and Wide buffers (short-term: 21%; long-term 93%) relative to controls after harvest. We did not find a treatment effect on total avian abundance. When assessing relationships between buffer width and site level abundance of four riparian specialists, we did not find strong evidence of reduced abundance in Narrow or Wide buffers. Silviculture regulations in this region dictate average buffer widths on small and large permanent streams that range from ~22–25 m. Guidelines for this region are within the range of buffers included in our study, in which we observed no evidence for avian species loss or for a decline in species abundance (including riparian associated species).

Simple SNP-based minimal marker genotyping for Humulus lupulus L. identification and variety validation.

BackgroundHop is an economically important crop for the Pacific Northwest USA as well as other regions of the world. It is a perennial crop with rhizomatous or clonal propagation system for varietal distribution. A big concern for growers as well as brewers is variety purity and questions are regularly posed to public agencies concerning the availability of genotype testing. Current means for genotyping are based upon 25 microsatellites that provides relatively accurate genotyping but cannot always differentiate sister-lines. In addition, numerous PCR runs (25) are required to complete this process and only a few laboratories exist that perform this service. A genotyping protocol based upon SNPs would enable rapid accurate genotyping that can be assayed at any laboratory facility set up for SNP-based genotyping. The results of this study arose from a larger project designed for whole genome association studies upon the USDA-ARS hop germplasm collection consisting of approximately 116 distinct hop varieties and germplasm (female lines) from around the world.ResultsThe original dataset that arose from partial sequencing of 121 genotypes resulted in the identification of 374,829 SNPs using TASSEL-UNEAK pipeline. After filtering out genotypes with more than 50 % missing data (5 genotypes) and SNP markers with more than 20 % missing data, 32,206 highly filtered SNP markers across 116 genotypes were identified and considered for this study. Minor allele frequency (MAF) was calculated for each SNP and ranked according to the most informative to least informative. Only those markers without missing data across genotypes as well as 60 % or less heterozygous gamete calls were considered for further analysis. Genetic distances among individuals in the study were calculated using the marker with the highest MAF value, then by using a combination of the two markers with highest MAF values and so on. This process was reiterated until a set of markers was identified that allowed for all genotypes in the study to be genetically differentiated from each other. Next, we compared genetic matrices calculated from the minimal marker sets [(Table 2; 6-, 7-, 8-, 10- and 12-marker set matrices] and that of a matrix calculated from a set of markers with no missing data across all 116 samples (1006 SNP markers). The minimum number of markers required to meet both specifications was a set of 7-markers (Table 3). These seven SNPs were then aligned with a genome assembly, and DNA sequence both upstream and downstream were used to identify primer sequences that can be used to develop seven amplicons for high resolution melting curve PCR detection or other SNP-based PCR detection methods.ConclusionsThis study identifies a set of 7 SNP markers that may prove useful for the identification and validation of hop varieties and accessions. Variety validation of unknown samples assumes that the variety under question has been included a priori in a discovery panel. These results are based upon in silica studies and markers need to be validated using different SNP marker technology upon a differential set of hop genotypes. The marker sequence data and suggested primer sets provide potential means to fingerprint hop varieties in most genetic laboratories utilizing SNP-marker technology.Electronic supplementary materialThe online version of this article (doi:10.1186/s13104-015-1492-2) contains supplementary material, which is available to authorized users.

Mitospore stages of Disciotis, Gyromitra and Morchella in the inland Pacific Northwest USA

Colonies of Costantinella species growing on soil, moss and woody debris in the autumn in the inland Pacific Northwest USA were established in culture. Five different mitospore taxa were distinguished based on colony color, presence or absence of setae and internal transcribed spacer region (ITS) rDNA amplicon size. Sequence data from the largest and second largest subunits of RNA polymerase II, translation elongation factor 1-α, D1 and D2 domains of nuclear large subunit rDNA and ITS were used to connect each of the distinct mitospore taxa to corresponding vernal-fruiting Pezizales, including Disciotis cf. venosa, Gyromitra cf. esculenta and three species of Morchella. Both meiospore and mitospore stages of Morchella brunnea and M. populiphila collected in spring and autumn within a meter of each other at two urban sites had identical multilocus haplotypes, providing evidence connecting the two stages of the life cycle. Among other Morchella mitospore stages collected, some had identical haplotypes to previously sampled meiospore stages, while others were distinct, possibly representing undescribed species. Mitospore isolates with sequences assigning them to Disciotis or Gyromitra had different haplotypes from meiospore stages occurring in the same area. Meiospore stages of Disciotis and Gyromitra sampled as part of the study were also genetically distinct from European collections of D. venosa and G. esculenta, indicating more diversity is present in these taxa than is reflected in the current taxonomy. The widespread occurrence of mitospore stages of these fungi suggests that the life cycles of morels, false morels and allied taxa are more complex than previously recognized.

Implications of climate change on wind erosion of agricultural lands in the Columbia plateau

Climate change may impact soil health and productivity as a result of accelerated or decelerated rates of erosion. Previous studies suggest a greater risk of wind erosion on arid and semi-arid lands due to loss of biomass under a future warmer climate. There have been no studies conducted to assess the impact of climate change on wind erosion in the Columbia Plateau of the Pacific Northwest United States where wind erosion of agricultural lands can cause exceedance of national air quality standards. The Wind Erosion Prediction System (WEPS) was used to assess wind erosion and PM10 (particulate matter ≤10µm in aerodynamic diameter) emissions under a future climate projected by downscaling 18 Global Climate Models (GCM) for a conservative emissions pathway. Wind erosion simulations were conducted at Lacrosse and Lind, WA and Moro, OR on a winter wheat-summer fallow (WW-SF) rotation and at Lind on an additional winter wheat-camelina-summer fallow (WW-Cam-SF) rotation. Each rotation was subject to conservation or conventional tillage practices for a baseline (1970–1999) and mid-21st century climate (2035–2064). A significant increase in temperature and nominal increases in precipitation were projected by an ensemble of climate models for the Columbia Plateau by the mid-21st century. Soil and PM10 losses were 25–84% lower for a mid-21st century climate, due in part to greater biomass production associated with CO2 fertilization and warmer temperatures. The reduction in soil and PM10 loss is projected to be more apparent for conservation tillage practices in the future. Soil and PM10 losses were greater from a WW-Cam-SF rotation than WW-SF rotation when conservation tillage practices were employed during the fallow phase of the rotations. Despite accounting for differences in the length of each rotation, annual soil and PM10 losses remained higher for the WW-Cam-SF rotation than the WW-SF rotation. Soil and PM10 losses were more variable across years during 1970–1999 than 2035–2064; however, small and inconsistent differences in the coefficient of variation in soil loss between 1970–1999 and 2035–2064 suggest similarity in climate extremes which govern wind erosion.

Nitrogen loss from windblown agricultural soils in the Columbia Plateau

Abstract Wind erosion of agricultural soils can degrade both air quality and soil productivity in the Columbia Plateau of the Pacific Northwest United States. Soils in the region contain fine particles that, when suspended, are highly susceptible to long range transport in the atmosphere. Nitrogen (N) associated with off-site transport of windblown particulate matter depletes the parent soil of nutrients important in sustaining the biological activity of soils. The objective of this study was to quantify the loss of N from eroding agricultural fields during high wind events. Soil eroded from fields subject to conventional tillage in winter wheat–summer fallow rotations in eastern Washington was trapped in creep and Big Spring Number Eight (BSNE) samplers installed on the leeward side of fields at heights of 0–1.5 m above the surface. The location of field sites varied over the 8 years of this study, but all sites were characterized by soils with a silt loam texture and annual precipitation of ⩽305 mm. Nitrogen content of the parent soil ranged from 0.063% to 0.090% while N content of sediment trapped by the samplers during high winds ranged from 0.053% to 0.101%. Enrichment ratios (ERs) for N ranged from 0.8 to 1.3, indicating the sediment was not highly enriched in N as compared with the parent soil. Nitrogen loss was estimated to range from 0.1 to 1.9 kg ha−1 during a high wind event. Nitrogen loss may be reduced by using conservation practices that have been proven effective in controlling wind erosion.