Treesearch

Salmon and steelhead habitat restoration projects in the Pacific Northwest have frequently relied on the use of engineered logjams—logs that are cabled together and placed in rivers to create pools where young salmon can live and grow in their first year before migrating to the ocean. Monitoring programs that rely on fish counts have shown that these human-made pools function as intended by providing a healthy habitat for juvenile fish.But do the logjams affect stream habitat beyond the areas of the pools? Could they benefit entire river reaches?Carlos Polivka, a research fishery biologist...

Ponderosa pine (Pinus ponderosa) forests are increasingly experiencing high-severity, stand-replacing fires. Whereas alterations to aboveground ecosystems have been extensively studied, little is known about soil fungal responses in fire-adapted ecosystems. We implement a chronosequence of four different fires that varied in time since fire, 2 years (2015) to 11 years (2006) and contained stands of high severity burned P. ponderosa in eastern Washington and compared their soil fungal communities to adjacent unburned plots. Using Illumina Miseq (ITS1), we examined changes in soil nutrients,...

In recent decades, scholars have developed ideas about therapeutic landscapes that explore how social processes, symbolism, and physical features generate diverse meanings. We examine here how therapeutic landscapes are produced and utilized for outdoor programs for military veterans, particularly veterans experiencing posttraumatic stress. Outdoor programs for veterans (OPVs) provide restorative opportunities through nature immersion and outdoor recreation. OPVs involve diverse social settings, activity types, durations, geographic and land management contexts, and degrees of therapeutic...

The amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd) is a skin pathogen that can cause the emerging infectious disease chytridiomycosis in susceptible species. It has been considered one of the most severe threats to amphibian biodiversity. We aimed to provide an updated compilation of global Bd occurrences by host taxon and geography, and with the larger global Bd dataset we reanalyzed Bd associations with environmental metrics at the world and regional scales. We also compared our Bd data compilation with a recent independent assessment to provide a more comprehensive count...

Smoke impacts from large wildfires are mounting, and the projection is for more such events in the future as the one experienced October 2017 in Northern California, and subsequently in 2018 and 2020. Further, the evidence is growing about the health impacts from these events which are also difficult to simulate. Therefore, we simulated air quality conditions using a suite of remotely-sensed data, surface observational data, chemical transport modeling with WRF-CMAQ, one data fusion, and three machine learning methods to arrive at datasets useful to air quality and health impact analyses....

Cover crops planted in the offseason are subjected to uncontrollable weather variables that limit agro-ecological services through modifications in growth and development. The growth of five cover crop species was investigated in response to an array of day/night temperatures, 17/9, 22/14, 27/19, 32/24, and 37/29 °C. Shoot and root parameters were measured 33 d after planting. Quadratic functions best described most of the root and shoot dynamics in response to increasing temperatures except for a linear response of plant height in crimson clover (Trifolium incarnatum) and mustard (Brassica...

Conservation of old-growth forests has become an increasingly important objective of Forest Service managers over the last three decades. The US Forest Service recently made changes to policies that prohibit cutting of live trees >53 cm (the “21-inch rule”). We review the disturbance ecology of dry and mesic old-growth forests of Oregon and contrast conservation policies for these two forest types. We describe the development of age-based alternatives to the 21-inch rule on the Klamath Reservation and in the Malheur National Forest in eastern Oregon. We conclude by outlining an adaptive...

Adult salmon sense when the time is right to leave the ocean and head for fresh water to spawn. But how do they know this? And how will climate change affect this cycle? Rebecca Flitcroft, a research fish biologist with the USDA Forest Service, Pacific Northwest Research Station, and colleagues took a closer look at the connection between migration patterns and stream conditions.They found that water temperature and the rate of streamflow appear to be two of the environmental conditions that precipitate the migration of salmon to their freshwater spawning grounds. This doesn’t bode well...

Altered flow regimes can contribute to dissociation between life history strategies and environmental conditions, leading to reduced persistence reported for many wildlife populations inhabiting regulated rivers. The Oregon spotted frog (Rana pretiosa) is a threatened species occurring in floodplains, ponds, and wetlands in the Pacific Northwest with a core range in Oregon, USA. All life stages of R. pretiosa are reliant on aquatic habitats, and inundation patterns across the phenological timeline can have implications for population success. We conducted capture–mark–recapture (CMR)...

Ranaviruses are emerging pathogens of poikilothermic vertebrates. In 2015 the Global Ranavirus Reporting System (GRRS) was established as a centralized, open access, online database for reports of the presence (and absence) of ranavirus around the globe. The GRRS has multiple data layers (e.g., location, date, host(s) species, and methods of detection) of use to those studying the epidemiology, ecology, and evolution of this group of viruses. Here we summarize the temporal, spatial, diagnostic, and host-taxonomic patterns of ranavirus reports in the GRRS. The number, distribution, and host...