Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 13 of 13

Full-Text Articles in Natural Resources Management and Policy

Performance Of Genetic Distance Metrics In Gravity And General Mixed Effects Models, Nathan B. Alexander, Crysta Gantz, Jane L. Remfert, Melanie A. Murphy Apr 2019

Performance Of Genetic Distance Metrics In Gravity And General Mixed Effects Models, Nathan B. Alexander, Crysta Gantz, Jane L. Remfert, Melanie A. Murphy

Environmental Science and Management Faculty Publications and Presentations

There are many causes for the genetic patterns that arise among populations across a landscape. Effective population size, natal site preference, geographic distance, or barriers to gene flow associated with landscape composition may work in opposition or in concert resulting in varying degrees of population differentiation. Here, we simulate 40 populations under 3 different ecological hypotheses of individual dispersal with random mating for 1500 generations, with scenarios: 1) dispersal and mating is dependent on habitat between populations, 2) dispersal and mating is dependent on individuals finding habitat similar to their natal habitat, and 3) dispersal and mating is dependent on …


Public Perceptions Of Mountain Lake Fisheries Management In National Parks, Ariana M. Chiapella, Max Nielsen-Pincus, Angela L. Strecker Sep 2018

Public Perceptions Of Mountain Lake Fisheries Management In National Parks, Ariana M. Chiapella, Max Nielsen-Pincus, Angela L. Strecker

Environmental Science and Management Faculty Publications and Presentations

The legacy of fish stocking in mountain lake ecosystems has left behind a challenge for land managers around the globe. In the US and Canada, historically fishless mountain lakes have been stocked with trout for over a century. These non-native trout have cascading ecosystem effects, and can accumulate atmospherically deposited contaminants. While the negative impacts of stocking in these ecosystems have become increasingly apparent, wilderness fishing has garnered cultural value in the angling community. As a result, public lands managers are left with conflicting priorities. National park managers across the western US are actively trying to reconcile the cultural and …


The Interactive Effect Of Multiple Stressors On Crustacean Zooplankton Communities In Montane Lakes, Jeffrey Thomas Brittain, Angela L. Strecker Feb 2018

The Interactive Effect Of Multiple Stressors On Crustacean Zooplankton Communities In Montane Lakes, Jeffrey Thomas Brittain, Angela L. Strecker

Environmental Science and Management Faculty Publications and Presentations

Nonnative fish introductions have altered thousands of naturally fishless montane lakes, resulting in cascading food web repercussions. Nitrogen deposition has been recognized as an anthropogenic contributor to acidification and eutrophication of freshwater ecosystems, which may affect the abundance and composition of planktonic communities. This study identified responses of zooplankton communities from two lakes (fish present versus absent) in Mount Rainier National Park to manipulations simulating an episodic disturbance of acidification and eutrophication via nitrogen addition in mesocosms. Zooplankton communities from lakes with different food web structure (i.e., fish present or absent) responded differently to the singular effects of acid and …


The Wildland-Urban Interface Raster Dataset Of Catalonia, Fermín J. Alcasena, Cody Evers, Cristina Vega-Garcia Jan 2018

The Wildland-Urban Interface Raster Dataset Of Catalonia, Fermín J. Alcasena, Cody Evers, Cristina Vega-Garcia

Environmental Science and Management Faculty Publications and Presentations

We provide the wildland urban interface (WUI) map of the autonomous community of Catalonia (Northeastern Spain). The map encompasses an area of some 3.21 million ha and is presented as a 150-m resolution raster dataset. Individual housing location, structure density and vegetation cover data were used to spatially assess in detail the interface, intermix and dispersed rural WUI communities with a geographical information system. Most WUI areas concentrate in the coastal belt where suburban sprawl has occurred nearby or within unmanaged forests. This geospatial information data provides an approximation of residential housing potential for loss given a wildfire, and represents …


Bending The Carbon Curve: Fire Management For Carbon Resilience Under Climate Change, E. Louise Loudermilk, Robert M. Scheller, Peter J. Weisberg, Alec M. Kretchun Jul 2017

Bending The Carbon Curve: Fire Management For Carbon Resilience Under Climate Change, E. Louise Loudermilk, Robert M. Scheller, Peter J. Weisberg, Alec M. Kretchun

Environmental Science and Management Faculty Publications and Presentations

Context: Forest landscapes are increasingly managed for fire resilience, particularly in the western US which has recently experienced drought and widespread, high-severity wildfires. Fuel reduction treatments have been effective where fires coincide with treated areas. Fuel treatments also have the potential to reduce drought-mortality if tree density is uncharacteristically high, and to increase long-term carbon storage by reducing high-severity fire probability.

Objective: Assess whether fuel treatments reduce fire intensity and spread and increase carbon storage under climate change.

Methods: We used a simulation modeling approach that couples a landscape model of forest disturbance and succession with an ecosystem model of …


The Effect Of Salinity Acclimation On The Upper Thermal Tolerance Threshold Of The European Green Crab, Lauren S. Muñoz-Tremblay, A. L. Kelley, Catherine De Rivera Jun 2017

The Effect Of Salinity Acclimation On The Upper Thermal Tolerance Threshold Of The European Green Crab, Lauren S. Muñoz-Tremblay, A. L. Kelley, Catherine De Rivera

Environmental Science and Management Faculty Publications and Presentations

Fluctuations in salinity and temperature, among other varying environmental conditions, are stressors in estuaries and may work together to alter the physiological response of organisms that inhabit such environments. Laboratory assessments that investigate how animals respond to multiple environmental stressors can provide an ecological framework for understanding physiological performance across varying conditions. In this study, European green crabs, Carcinus maenas, were collected from Seadrift Lagoon, California, USA (37°54′27.82″N, 122°40′19.56″W) and were lab-acclimated at three different salinity concentrations typical of many estuaries: 15, 25, and 35 PSU at 12 °C (± 1 °C). After acclimation, crabs from each salinity treatment experienced …


Competition Amplifies Drought Stress In Forests Across Broad Climatic And Compositional Gradients, Kelly E. Gleason, John B. Bradford, Alessandra Bottero, Anthony W. D'Amato, Shawn Fraver, Brian J. Palik, Michael A. Battaglia, Louis Iverson, Laura Kenefic, Christel C. Kern May 2017

Competition Amplifies Drought Stress In Forests Across Broad Climatic And Compositional Gradients, Kelly E. Gleason, John B. Bradford, Alessandra Bottero, Anthony W. D'Amato, Shawn Fraver, Brian J. Palik, Michael A. Battaglia, Louis Iverson, Laura Kenefic, Christel C. Kern

Environmental Science and Management Faculty Publications and Presentations

Forests around the world are experiencing increasingly severe droughts and elevated competitive intensity due to increased tree density. However, the influence of interactions between drought and competition on forest growth remains poorly understood. Using a unique dataset of stand-scale dendrochronology sampled from 6405 trees, we quantified how annual growth of entire tree populations responds to drought and competition in eight, long-term (multi-decadal), experiments with replicated levels of density (e.g., competitive intensity) arrayed across a broad climatic and compositional gradient. Forest growth (cumulative individual tree growth within a stand) declined during drought, especially during more severe drought in drier climates. Forest …


Past, Present, And Future Of Ecological Integrity Assessment For Fresh Waters, Lauren M. Kuehne, Julian D. Olden, Angela L. Strecker, Joshua J. Lawler, David M. Theobald Apr 2017

Past, Present, And Future Of Ecological Integrity Assessment For Fresh Waters, Lauren M. Kuehne, Julian D. Olden, Angela L. Strecker, Joshua J. Lawler, David M. Theobald

Environmental Science and Management Faculty Publications and Presentations

One of the most influential environmental laws in the US – the 1972 Clean Water Act – included the visionary objective of maintaining and restoring aquatic ecological integrity. However, the efficacy of the Act depends on how integrity is assessed. Reviewing the assessment literature for fresh waters over the past 40 years, we found evidence of methodological trends toward increased repeatability, transferability, and robustness of assessments over time. However, implementation gaps were revealed, based on the relatively weak linkages to freshwater policies, stakeholder involvement, emerging threats, and conservation opportunities. A related survey of assessment practitioners underscored the disparity between need …


Increased Habitat Connectivity Homogenizes Freshwater Communities: Historical And Landscape Perspectives, Angela L. Strecker, Jeffrey Thomas Brittain Feb 2017

Increased Habitat Connectivity Homogenizes Freshwater Communities: Historical And Landscape Perspectives, Angela L. Strecker, Jeffrey Thomas Brittain

Environmental Science and Management Faculty Publications and Presentations

  1. Increases in habitat connectivity can have consequences for taxonomic, functional, and genetic diversity of communities. Previously isolated aquatic habitats were connected with canals and pipelines in the largest water development project in the US history, the Columbia Basin Project (CBP; eastern Washington, USA), which also altered environmental conditions; however, the ecological consequences are largely unknown.

  2. Using a historical dataset, we examined long-term patterns in zooplankton communities, water chemistry and clarity, testing the hypothesis that increased connectivity will result in taxonomic homogenization. Further, we tested contemporary drivers of communities using a comprehensive set of environmental and landscape variables.

  3. Waterbodies were sampled …


Developing A Representative Snow-Monitoring Network In A Forested Mountain Watershed, Kelly E. Gleason, Anne Nolin, Travis R. Roth Feb 2017

Developing A Representative Snow-Monitoring Network In A Forested Mountain Watershed, Kelly E. Gleason, Anne Nolin, Travis R. Roth

Environmental Science and Management Faculty Publications and Presentations

A challenge in establishing new ground-based stations for monitoring snowpack accumulation and ablation is to locate the sites in areas that represent the key processes affecting snow accumulation and ablation. This is especially challenging in forested montane watersheds where the combined effects of terrain, climate, and land cover affect seasonal snowpack. We present a coupled modeling approach used to objectively identify representative snow-monitoring locations in a forested watershed in the western Oregon Cascades mountain range. We used a binary regression tree (BRT) non-parametric statistical model to classify peak snow water equivalent (SWE) based on physiographic landscape characteristics in an average …


Understanding The Links Between Cyanobacteria Physiology And Hydrodynamics May Help Find Adaption Strategies For Toxic Blooms, John Rueter Oct 2016

Understanding The Links Between Cyanobacteria Physiology And Hydrodynamics May Help Find Adaption Strategies For Toxic Blooms, John Rueter

Environmental Science and Management Faculty Publications and Presentations

Even though we are managing lakes to decrease algal blooms overall, harmful algal blooms seem to be showing up more and more frequently. Although the word “blooms” connotes dominance and rapid growth, dangerous accumulations of cyanobacteria can occur because of combinations of physiological advantages and particular weather and hydrodynamic conditions. I am particularly interested in specific conditions that might favor Aphanizomenon versus those that might favor Microcystis in Upper Klamath and Agency Lakes. Aphanizomenon is a nuisance and large blooms can lead to oxygen depletion and fish deaths. Microcystis can both be a nuisance and is toxic. The comparison of …


Type And Timing Of Stream Flow Changes In Urbanizing Watersheds In The Eastern U.S., Kristina G. Hopkins, Nathaniel B. Morse, Daniel J. Bain, Neil D. Bettez, Nancy B. Grimm, Jennifer L. Morse, Monica M. Palta Jun 2015

Type And Timing Of Stream Flow Changes In Urbanizing Watersheds In The Eastern U.S., Kristina G. Hopkins, Nathaniel B. Morse, Daniel J. Bain, Neil D. Bettez, Nancy B. Grimm, Jennifer L. Morse, Monica M. Palta

Environmental Science and Management Faculty Publications and Presentations

Linking the type and timing of hydrologic changes with patterns of urban growth is essential to identifying the underlying mechanisms that drive declines in urban aquatic ecosystems. In six urbanizing watersheds surrounding three U.S. cities (Baltimore, MD, Boston, MA, and Pittsburgh, PA), we reconstructed the history of development patterns since 1900 and assessed the magnitude and timing of stream flow changes during watershed development. Development reconstructions indicated that the majority of watershed development occurred during a period of peak population growth, typically between 1950 and 1970. Stream flow records indicated significant increases in annual frequency of high-flow events in all …


Effectiveness Of Fuel Treatments For Mitigating Wildfire Risk And Sequestering Forest Carbon: A Case Study In The Lake Tahoe Basin, E. Louise Loudermilk, Alison Stanton, Robert M. Scheller, Thomas E. Dilts, Peter J. Weisberg, Carl Skinner, Jian Yang Mar 2014

Effectiveness Of Fuel Treatments For Mitigating Wildfire Risk And Sequestering Forest Carbon: A Case Study In The Lake Tahoe Basin, E. Louise Loudermilk, Alison Stanton, Robert M. Scheller, Thomas E. Dilts, Peter J. Weisberg, Carl Skinner, Jian Yang

Environmental Science and Management Faculty Publications and Presentations

Fuel-reduction treatments are used extensively to reduce wildfire risk and restore forest diversity and function. In the near future, increasing regulation of carbon (C) emissions may force forest managers to balance the use of fuel treatments for reducing wildfire risk against an alternative goal of C sequestration. The objective of this study was to evaluate how long-term fuel treatments mitigate wildfires and affect forest C. For the Lake Tahoe Basin in the central Sierra Nevada, USA, fuel treatment efficiency was explored with a landscape-scale simulation model, LANDIS-II, using five fuel treatment scenarios and two (contemporary and potential future) fire regimes. …