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Olympia, WA, United States

Henny C.J.,U.S. Geological Survey | Grove R.A.,U.S. Geological Survey | Kaiser J.L.,U.S. Geological Survey | Johnson B.L.,U.S. Geological Survey | And 2 more authors.

Several polybrominated biphenyl ether (PBDE) congeners were found in all 175 osprey (Pandion haliaetus) eggs collected from the Columbia River Basin between 2002 and 2009. ∑PBDE concentrations in 2008-2009 were highest in osprey eggs from the two lowest flow rivers studied; however, each river flowed through relatively large and populous metropolitan areas (Boise, Idaho and Spokane, Washington). We used the volume of Wastewater Treatment Plant (WWTP) discharge, a known source of PBDEs, as a measure of human activity at a location, and combined with river flow (both converted to millions of gallons/day) created a novel approach (an approximate Dilution Index) to relate waterborne contaminants to levels of these contaminants that reach avian eggs. This approach provided a useful understanding of the spatial osprey egg concentration patterns observed. Individual osprey egg concentrations along the Upper Willamette River co-varied with the Dilution Index, while combined egg data (geometric means) from rivers or segments of rivers showed a strong, significant relationship to the Dilution Index with one exception, the Boise River. There, we believe osprey egg concentrations were lower than expected because Boise River ospreys foraged perhaps 50-75% of the time off the river at ponds and lakes stocked with fish that contained relatively low ∑PBDE concentrations. Our limited temporal data at specific localities (2004-2009) suggests that ∑PBDE concentrations in osprey eggs peaked between 2005 and 2007, and then decreased, perhaps in response to penta- and octa-PBDE technical mixtures no longer being used in the USA after 2004. Empirical estimates of biomagnification factors (BMFs) from fish to osprey eggs were 3.76-7.52 on a wet weight (ww) basis or 4.37-11.0 lipid weight. Our earlier osprey study suggested that ∑PBDE egg concentrations >1,000 ng/g ww may reduce osprey reproductive success. Only two of the study areas sampled in 2008-2009 contained individual eggs with ∑PBDE concentrations >1,000 ng/g, and non-significant (P > 0.30) negative relationships were found between ∑PBDEs and reproductive success. Additional monitoring is required to confirm not only the apparent decline in PBDE concentrations in osprey eggs that occurred during this study, but also to better understand the relationship between PBDEs in eggs and reproductive success. © 2011 Springer Science+Business Media, LLC. Source

Larson C.A.,Environmental Assessment Program | Adumatioge L.,University of Texas at Arlington | Passy S.I.,University of Texas at Arlington
Microbial Ecology

The role of the number of limiting resources (NLR) on species richness has been the subject of much theoretical and experimental work. However, how the NLR controls temporal beta diversity and the processes of community assembly is not well understood. To address this knowledge gap, we initiated a series of laboratory microcosm experiments, exposing periphyton communities to a gradient of NLR from 0 to 3, generated by supplementation with nitrogen, phosphorus, iron, and all their combinations. We hypothesized that similarly to alpha diversity, shown to decrease with the NLR in benthic algae, temporal beta diversity would also decline due to filtering. Additionally, we predicted that the NLR would also affect turnover and community nestedness, which would show opposing responses. Indeed, as the NLR increased, temporal beta diversity decreased; turnover, indicative of competition, decreased; and nestedness, suggestive of complementarity, increased. Finally, the NLR determined the role of deterministic versus stochastic processes in community assembly, showing respectively an increasing and a decreasing trend. These results imply that the NLR has a much greater, yet still unappreciated influence on producer communities, constraining not only alpha diversity but also temporal dynamics and community assembly. © 2016 Springer Science+Business Media New York Source

Janisch J.E.,Environmental Assessment Program | Wondzell S.M.,Jefferson Lab | Ehinger W.J.,Environmental Assessment Program
Forest Ecology and Management

We examined stream temperature response to forest harvest in small (<9. ha) forested headwater catchments in western Washington, USA over a seven year period (2002-2008). These streams have very low discharge in late summer X̄≈0.3Ls-1) and many become spatially intermittent. We used a before-after, control-impact (BACI) study design to contrast the effect of clearcut logging with two riparian buffer designs, a continuous buffer and a patch buffer. We focused on maximum daily temperature throughout July and August, expecting to see large temperature increases in the clearcut streams (n= 5), much smaller increases in the continuously buffered streams (n= 6), with the patch-buffered streams (n= 5) intermediate. Statistical analyses indicated that all treatments resulted in significant (α= 0.05) increases in stream temperature. In the first year after logging, daily maximum temperatures during July and August increased in clearcut catchments by an average of 1.5 °C (range 0.2 to 3.6 °C), in patch-buffered catchments by 0.6 °C (range -0.1 to 1.2 °C), and in continuously buffered catchments by 1.1 °C (range 0.0 to 2.8 °C). Temperature responses were highly variable within treatments and, contrary to our expectations, stream temperature increases were small and did not follow expected trends among the treatment types. We conducted further analyses in an attempt to identify variables controlling the magnitude of post-harvest treatment responses. These analyses showed that the amount of canopy cover retained in the riparian buffer was not a strong explanatory variable. Instead, spatially intermittent streams with short surface-flowing extent above the monitoring station and usually characterized by coarse-textured streambed sediment tended to be thermally unresponsive. In contrast, streams with longer surface-flowing extent above the monitoring station and streams with substantial stream-adjacent wetlands, both of which were usually characterized by fine-textured streambed sediment, were thermally responsive. Overall, the area of surface water exposed to the ambient environment seemed to best explain our aggregate results. Results from our study suggest that very small headwater streams may be fundamentally different than many larger streams because factors other than shade from the overstory tree canopy can have sufficient influence on stream energy budgets to strongly moderate stream temperatures even following complete removal of the overstory canopy. © 2011 Elsevier B.V. Source

Janisch J.E.,Environmental Assessment Program | Foster A.D.,U.S. Department of Agriculture | Ehinger W.J.,Environmental Assessment Program
Forest Ecology and Management

In 2002, we initiated a study to clarify the response of headwater catchments to logging on timberlands in the Coast Range of Washington, USA. Most of the predominantly first-order streams studied (summer low flows typically<0.3Ls-1) were hydrologically complex, consisting of a main surface channel connected to multiple, small wetlands. To better understand the forest management implications of headwater systems with two surface hydrology components of potentially differing areal extents (i.e., broad wetlands and narrow, channelized flow), we examined in more detail the wetlands associated with 30 headwater channels. On average, 2.3 wetlands occurred per channel. All 68 surveyed wetlands were, individually, smaller than 0.1ha, which is a minimum survey-and-manage size criterion for forested wetlands in use in the Pacific Northwest. Seventy-nine percent of the wetlands surveyed by the full-triad method met regional wetland triad criteria for wetland delineation (qualifying wetland soils, hydrology, and vegetation indicators). These headwater wetlands were associated with several landscape variables: (1) northerly-facing catchments, (2) perennial surface water, and (3) down, channel-associated large wood originating from adjacent riparian forest. Our results show that small forested wetlands are quite common and that the surface area of small wetlands can rival the surface area of the associated first-order streams. This initial effort to quantify characteristics of small headwater wetlands suggests small wetlands could dominate or influence headwater surface area processes including those associated with stream responses to disturbances such as logging. © 2011 Elsevier B.V. Source

Long E.R.,Environmental Assessment Program | Dutch M.,Environmental Assessment Program | Weakland S.,Environmental Assessment Program | Chandramouli B.,Axys Analytical Services | Benskin J.P.,Axys Analytical Services
Environmental Toxicology and Chemistry

Concentrations of 119 pharmaceuticals and personal care products (PPCPs) and 13 perfluoroalkyl substances (PFASs) in marine sediments measured throughout Puget Sound (n=10) and Bellingham Bay (n=30), Washington, USA, are reported. These data are among the first measurements of PPCPs and PFASs in marine sediments from the Pacific Northwest and provide a comparison to previous measurements of these chemicals in influent, effluent, and biosolids from municipal wastewater treatment plants throughout the region. The concentrations of both PPCPs and PFASs in sediments from Puget Sound and Bellingham Bay ranged from very low to non-detectable for most compounds. Only 14 of the 119 PPCPs and 3 of 13 PFASs were quantifiable in sediments. Diphenhydramine (an antihistamine) was most frequently detected (87.5% of samples), with a maximum concentration of 4.81ng/g dry weight and an estimated mean detected concentration of 1.68ng/g. Triclocarban (an antibacterial) was detected in 35.0% of the samples, with a maximum concentration of 16.6ng/g dry weight. Perfluoroalkyl substances were detected in 2.5% of analyses. Perfluorobutanoate, perfluorooctane sulfonate, and perfluorooctane sulfonamide were detected in 7, 5, and 1 sample(s) each, respectively, with the highest concentrations observed for perfluorooctane sulfonate (1.5ng/g). Detected concentrations were often highest within the industrial harbor in Bellingham Bay and near the cities of Seattle and Bremerton. © 2013 SETAC. Source

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