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A Multi-Year Longitudinal Study of Water Quality Parameters in Four Salmon-Bearing and Recreational Streams on Mount Hood, Oregon
Get PDFFour streams-Clear Fork, Lost Creek, Camp Creek and Still Creek-in northwestern Oregon's Sandy River Basin were monitored for temperature, dissolved oxygen levels, and fecal bacterial concentrations in a multi-year analysis examining stream health for recreational users and anchor habitat for Pacific Salmon. Temperatures were recorded using micro -T temperature loggers at 15 locations, during 22 July -5 September 2006, 2 July -4 September 2007, 20 June -7 September 2008, 23 June -9 September 2009, and 2 July -9 September 2010. The Seven-Day Average Maximum water temperature (7-DAM) of 13° C was used as a reference value for the biological limit governing suitable salmonid spawning and egg incubation conditions. The maximum 7-DAM temperatures occurred on different dates and all streams neared or exceeded the 13° C standard at least once each summer. Dissolved oxygen levels were measured at weekly or longer intervals in 2006, 2007, 2008, and 2009. Dissolved oxygen levels fell below the 9.0 ppm standard for Clear Fork on almost half the sampling dates in 2006, 2007, and 2009. Concentrations of the bacterial genus Enterococcus were measured as an indicator of fecal contamination. Samples were collected at 15 sites along the four streams. Weekly samples were collected during a 9 week period from July -September 2007, an 11 week period from June -September 2008, and an 11 week period from June September 2009. Enterococcus counts exceeded the federal recommended national criterion value of 61 colony forming units (CFU) per 100 mL every year in Camp Creek and occasionally elsewhere, with exceedances trending towards late summer
Utilizing Fishermen Knowledge and Expertise: Keys to Success for Collaborative Fisheries Research
Get PDFCollaborative fisheries research provides a mechanism for integrating the unique knowledge, experience, and skills of fishermen and scientists. It is a joint intellectual endeavor that begins with the inception of a project and continues until its final stages, with each group having mutual investment in-and ownership of-the project. Collaborative fisheries research promotes communication and trust among fishermen, scientists, and managers and can provide much-needed scientifically valid data for fisheries management. It can enhance federal and state management data collection programs, which span broad sections of coastline, by increasing the ability to detect changes in local metapopulations that may be over-fished or underutilized. We describe a methodology for conducting collaborative fisheries surveys and apply it to marine protected areas along the central California coast. During a series of workshops in 2006, attended by members of the fishing, academic, environmental, and management communities, protocols were established for conducting hook-and-line surveys collaboratively with commercial passenger fishing vessel captains and volunteer recreational anglers. The protocols have been implemented annually since 2007. This case study highlights the effectiveness of-and the essential steps in-developing our collaborative fisheries research and monitoring projects
Thomas Hobbes and the Duke of Newcastle: A Study in the Mutuality of Patronage before the Establishment of the Royal Society
Get PDFThis study shows how patronage framed and fashioned the careers of Thomas Hobbes and
his patron William Cavendish, the earl of Newcastle. Newcastle's protection allowed
Hobbes to articulate heterodox ideas without immediate fear of reprisal. It also enabled
him to solidify his status as a gentleman and the intellectual equal of both his mentor and
other natural philosophers. When Hobbes offered his ideas on optics, motion, politics, and
philosophy as gifts to his patron, he was reaffirming his own honor and status while
acknowledging Newcastle's power. Hobbes always acted as if he was operating in the
space created by a noble patron, even after this place had been transformed by the Royal
Society. For Newcastle, intellectual patronage reaffirmed the status and honor he had lost
during the English Civil War. Newcastle tried to establish himself as a philosopher in his
own right by applying Hobbesian ideas to studies of politics, horsemanship, and swordsmanship.
Thus, the rewards of patronage were mutua
Review of the book The Jews of Vienna and the First World War; Reconstructing a National Identity: The Jews of Habsburg Austria during World War I
Get PDFPredictive mapping of forest composition and structure with direct gradient analysis and nearest-neighbor imputation in coastal Oregon, U.S.A.
Get PDFSpatially explicit information on the species composition and structure of forest vegetation is needed at broad spatial scales for natural resource policy analysis and ecological research. We present a method for predictive vegetation mapping that applies direct gradient analysis and nearest-neighbor imputation to ascribe detailed ground attributes of vegetation to each pixel in a digital landscape map. The gradient nearest neighbor method integrates vegetation measurements from regional grids of field plots, mapped environmental data, and Landsat Thematic Mapper (TM)
imagery. In the Oregon coastal province, species gradients were most strongly associated with regional climate and
geographic location, whereas variation in forest structure was best explained by Landsat TM variables. At the regional
level, mapped predictions represented the range of variability in the sample data, and predicted area by vegetation type
closely matched sample-based estimates. At the site level, mapped predictions maintained the covariance structure among multiple response variables. Prediction accuracy for tree species occurrence and several measures of vegetation structure and composition was good to moderate. Vegetation maps produced with the gradient nearest neighbor method are appropriately used for regional-level planning, policy analysis, and research, not to guide local management decisions
Coarse woody debris in forest regions of Russia
Get PDFTo assess regional stores of coarse woody debris (CWD) in seven major forest regions of Russia, we combined data collected as part of the routine forest inventory with measurements in 1044 sample plots and the results of density sampling of 922 dead trees. The stores of CWD in the western part of Russia (St. Petersburg, Central, Khanty- Mansi, and Novosibirsk regions) were on average lower (14–20 m3/ha or 4.0–5.8 Mg/ha) than in the East Siberian and Far Eastern regions (40–51 m3/ha or 11.0–14.4 Mg/ha). The difference in CWD stores was particularly large between young forests in two western regions (2.4 Mg/ha in St. Petersburg and 3.4 Mg/ha in the Central region) and in the east
(20.4–24.4 Mg/ha). This difference is associated with the prevailing disturbance type: clear-cut harvest in western Russia
and natural disturbances in the east. Analysis of variance in CWD stores indicates that region, dominant species, forest age group, productivity class, and interactions of these factors explain 87–88% of the total variance and the strongest effects are for age group and region. Lower stores of CWD within the intensively managed forest regions suggest that further expansion of forest use in many regions of Russia may reduce regional stores of CWD and carbon
Underplanted conifer seedling survival and growth in thinned Douglas-fir stands
Get PDFIn a multilevel study to determine limits to underplanted conifer seedling growth, Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), grand fir (Abies grandis (Dougl. ex D. Don) Lindl.), western redcedar (Thuja plicata Donn ex D. Don), and western hemlock (Tsuga heterophylla (Raf.) Sarg.) seedlings were planted beneath second-growth Douglas-fir stands that had been thinned to basal areas ranging from 16 to 31 m2/ha. Understory vegetation was treated with a broadcast herbicide application prior to thinning, a directed release herbicide application 2 years later, or no treatment beyond harvest disturbance. Residual overstory density was negatively correlated with percent survival for all
four species. Broadcast herbicide application improved survival of grand fir and western hemlock. Western redcedar,
grand fir, and western hemlock stem volumes were inversely related to overstory tree density, and this effect increased
over time. There was a strong indication that this was also the case for Douglas-fir. Reduction of competing understory
vegetation resulted in larger fourth-year stem volumes in grand fir and western hemlock