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Full-Text Articles in Physical Sciences and Mathematics

Beaver (Castor Canadensis) Of The Salinas River: A Human Dimensions-Inclusive Overview For Assessing Landscape-Scale Beaver-Assisted Restoration Opportunities, Stuart Christian Suplick Jul 2019

Beaver (Castor Canadensis) Of The Salinas River: A Human Dimensions-Inclusive Overview For Assessing Landscape-Scale Beaver-Assisted Restoration Opportunities, Stuart Christian Suplick

Natural Resources Management and Environmental Sciences

Across the western United States, researchers are increasingly working with beaver (Castor canadensis) for process-based stream and watershed restoration. One recently-developed geographic information system-based tool, the Beaver Restoration Assessment Tool (BRAT), analyzes opportunities for beaver-assisted restoration (BAR) at a landscape-scale. However, this tool benefits significantly from human dimensions-inclusive, basin-centralized beaver knowledge for proper interpretation. Unfortunately, this information is scattered or absent in most semi-arid and arid southern California basins. This study thus sought to gather and produce this information through an explorative, benefits-maximizing approach to landscape-scale BAR opportunities assessment in one of these basins, the Salinas River. 49.2 …


Column Tests Of Nitrate Breakthrough Behavior In Subsurface Sediments To Understand Transport In The Root-Zone, Rebecca Sally Haworth, Emma Rose Goodwin Jun 2018

Column Tests Of Nitrate Breakthrough Behavior In Subsurface Sediments To Understand Transport In The Root-Zone, Rebecca Sally Haworth, Emma Rose Goodwin

Natural Resources Management and Environmental Sciences

Nitrate has become an increasingly ubiquitous pollutant in surface and groundwater, posing a threat to hu- man health and ecosystems. Nitrogen is a necessary nutrient for plant growth and is limiting in many soils. As a result, farmers often add nitrogen to soil in a usable form such as nitrate, nitrite, or ammonia through the addition of fertilizer.


Soil Science Lesson Plan For The Cal Poly Learn By Doing Lab, Kelsey Ormonde May 2017

Soil Science Lesson Plan For The Cal Poly Learn By Doing Lab, Kelsey Ormonde

Natural Resources Management and Environmental Sciences

To increase interest in soil science and other related sciences, educational materials need to be tailored to appeal to younger students. The purpose of this project was to create a soil science lesson plan that could be utilized by the Cal Poly Learn By Doing Lab. Information from several articles, textbooks, lesson plans, and websites was reviewed to create a soil science lesson plan for students in 5-8th grade. The lesson plan focused on the three sub-disciplines of soil science; physical, chemical, and biological. Activities were created to correspond to the three sub-disciplines. Alternate activities were created to allow …


Digitization Of Disturbance History For Swanton Pacific Ranch From 1989 To 2015, Daniel Mcquillan Apr 2015

Digitization Of Disturbance History For Swanton Pacific Ranch From 1989 To 2015, Daniel Mcquillan

Natural Resources Management and Environmental Sciences

No abstract provided.


Leadership - A Lifetime Quest For Excellence, Douglas D. Piirto Nov 2014

Leadership - A Lifetime Quest For Excellence, Douglas D. Piirto

Natural Resources Management and Environmental Sciences

This paper is written for aspiring leaders and managers. Each of us will be asked to lead, manage, and/or follow at various times and in many different situations in our journey of life. This paper is written to assist aspiring leaders and managers discover and develop their leadership and management abilities.

The paper is organized per the following outline:

  • Introduction
  • Establishing Credibility
  • Enthusiasm and Desirable Habits of Effective People
  • Leadership and Management
  • Situational Analysis and Leadership Styles
    • Leadership as a Student [discussed in Introduction)
    • Leadership as a Forest Scientist
    • Leadership as a Teacher and Professor
    • Leadership as a Department Head …


Investigation Of Thermochemical Biorefinery Sizing And Environmental Sustainability Impacts For Conventional Supply System And Distributed Pre-Processing Supply System Designs, David J. Muth Jr, Matthew H. Langholtz, Eric Cd Tan, Jacob J. Jacobson, Amy Schwab, May M. Wu, Andrew Argo, Craig C. Brandt, Kara G. Cafferty, Yi-Wen Chiu, Abhijit Dutta, Laurence M. Eaton, Erin M. Searcy Jul 2014

Investigation Of Thermochemical Biorefinery Sizing And Environmental Sustainability Impacts For Conventional Supply System And Distributed Pre-Processing Supply System Designs, David J. Muth Jr, Matthew H. Langholtz, Eric Cd Tan, Jacob J. Jacobson, Amy Schwab, May M. Wu, Andrew Argo, Craig C. Brandt, Kara G. Cafferty, Yi-Wen Chiu, Abhijit Dutta, Laurence M. Eaton, Erin M. Searcy

Natural Resources Management and Environmental Sciences

The 2011 US Billion-Ton Update estimates that by 2030 there will be enough agricultural and forest resources to sustainably provide at least one billion dry tons of biomass annually, enough to displace approximately 30% of the country's current petroleum consumption. A portion of these resources are inaccessible at current cost targets with conventional feedstock supply systems because of their remoteness or low yields. Reliable analyses and projections of US biofuels production depend on assumptions about the supply system and biorefinery capacity, which, in turn, depend upon economic value, feedstock logistics, and sustainability. A cross-functional team has examined combinations of advances …


Investigating Meter Scale Topographic Variation As A Factor Of Monterey Pine (Pinus Radiata) Growing Conditions At Kenneth Norris Rancho Marino Reserve, Cambria, Ca, William J. Meyst Jun 2014

Investigating Meter Scale Topographic Variation As A Factor Of Monterey Pine (Pinus Radiata) Growing Conditions At Kenneth Norris Rancho Marino Reserve, Cambria, Ca, William J. Meyst

Natural Resources Management and Environmental Sciences

Endemic Monterey pine (Pinus radiata) is limited to three locations in California due to its unique ecological requirements. This project was conducted to investigate spatial growth patterns ofMonterey pine over complex ground surfaces. The coastal hills of Rancho Marino Reserve, Cambria, were surveyed using four 150-m transects to quantify and record ground surface features and growing conditions ofMonterey pine. Changes in elevation of each transect were measured using an Abney level. Linear ground surfaces were found at 86% (344 of 400) of survey nodes. Convex ground surfaces were found at 10.5% of survey nodes (42 of 400). Of …


Relationship Between Soil Moisture And Electrical Resistivity In A Native Meadow And Forest Ecotone, Todd Davis Jun 2014

Relationship Between Soil Moisture And Electrical Resistivity In A Native Meadow And Forest Ecotone, Todd Davis

Natural Resources Management and Environmental Sciences

No abstract provided.


Theory Of Transient Streaming Potentials In Coupled Unconfined Aquifer-Unsaturated Zone Flow To A Well, Bwalya Malama Apr 2014

Theory Of Transient Streaming Potentials In Coupled Unconfined Aquifer-Unsaturated Zone Flow To A Well, Bwalya Malama

Natural Resources Management and Environmental Sciences

A semianalytical solution is presented for transient streaming potentials associated with flow to a pumping well in an unconfined aquifer, taking into account the effect of flow in the unsaturated zone above the water table. Flow in the unsaturated zone is modeled with a linearized form of Richards' equation using an exponential model for soil moisture retention and unsaturated hydraulic conductivity. Archie's law is invoked for unsaturated electrical conductivity. The unsaturated electrokinetic coupling coefficient is modeled with a decaying exponential, where the maximum value is at and below the water table. The coupled flow and electrokinetic problem is solved using …


Classification Of Plot-Level Fire-Caused Tree Mortality In A Redwood Forest Using Digital Orthophotography And Lidar, Brian D. Bishop, Brian C. Dietterick, Russell A. White, Tom B. Mastin Mar 2014

Classification Of Plot-Level Fire-Caused Tree Mortality In A Redwood Forest Using Digital Orthophotography And Lidar, Brian D. Bishop, Brian C. Dietterick, Russell A. White, Tom B. Mastin

Natural Resources Management and Environmental Sciences

Aerial and satellite imagery are widely used to assess the severity and impact of wildfires. Light detection and ranging (LiDAR) is a newer remote sensing technology that has demonstrated utility in measuring vegetation structure. Combined use of imagery and LiDAR may improve the assessment of wildfire impacts compared to imagery alone. Estimation of tree mortality at the plot scale could serve for more rapid, broad-scale, and lower cost post-fire assessments than feasible through field assessment. We assessed the accuracy of classifying color-infrared imagery in combination with post-fire LiDAR, and with differenced (pre- and post-fire) LiDAR, in estimating plot percent mortality …


Life-Cycle Water Quantity And Water Quality Implications Of Biofuels, May Wu, Zhonglong Zhang, Yi-Wen Chiu Mar 2014

Life-Cycle Water Quantity And Water Quality Implications Of Biofuels, May Wu, Zhonglong Zhang, Yi-Wen Chiu

Natural Resources Management and Environmental Sciences

Water consumption and water quality continue to be key factors affecting environmental sustainability in biofuel production. This review covers the findings from biofuel water analyses published over the past 2 years to underscore the progress made, and to highlight advancements in understanding the interactions among increased production and water demand, water resource availability, and potential changes in water quality. We focus on two key areas: water footprint assessment and watershed modeling. Results revealed that miscanthus-, switchgrass-, and forest wood-based biofuels all have promising blue and grey water footprints. Alternative water resources have been explored for algae production, and challenges remain. …


Common Core 4th Grade Environmental Science Lesson Plans For California Teachers, Gillian Schoenfeld Dec 2013

Common Core 4th Grade Environmental Science Lesson Plans For California Teachers, Gillian Schoenfeld

Natural Resources Management and Environmental Sciences

This project and its analyses were conducted to assist California fourth grade elementary school teachers in adjusting to teaching Common Core standards and science curriculum in their classrooms. The project included the creation of lesson plans, which could be utilized throughout the state of California.

As the Common Core standards, California’s Next Generation Science Standards for K- 12, were just proposed in June of 2013, these lesson plans would help teachers update their lessons and provide them materials and concepts of how to do so. These lessons provide higher-order thinking for students, which is the whole concept of the new …


Geoelectrical Detection Of Water Table Depth At Two Locations In The Los Osos Groundwater Basin, Hallie A. Douglas Dec 2013

Geoelectrical Detection Of Water Table Depth At Two Locations In The Los Osos Groundwater Basin, Hallie A. Douglas

Natural Resources Management and Environmental Sciences

The city of Los Osos sits on top of a coastal groundwater aquifer which is the sole supplier of all its residential, agricultural, and industrial water needs. Lacking a sewer system, the upper aquifer became progressively contaminated with nitrates over several decades. Groundwater pumping eventually shifted to the lower aquifer, however seawater intrusion of the lower aquifer caused by over-pumping has further degraded water quality. The Los Osos groundwater basin provides an excellent field region to examine the utility of geophysical methods for characterizing aquifer structure. In this study shallow (<20 >m) electrical resistivity imaging methods were performed at two …


Road Cuts And Atterberg Limits Of Little Creek Road, Christopher A. Marquis Oct 2013

Road Cuts And Atterberg Limits Of Little Creek Road, Christopher A. Marquis

Natural Resources Management and Environmental Sciences

This senior project examined road cuts and soil adjacent to the road cut, along Little Creek road. Contrasting a landslide hillslope complex to a hillslope drainage complex, the project also compared the organic soil horizon to the mineral soil horizon in both soil units. The soils were analyzed using qualitative and quantitative measures of soil properties. The project utilized a road cut inventory to note the characteristics of the road cut such as presence of rill erosion, rock outcrop and sloping degree of the road cut. The project derived the plasticity index for both organic and mineral horizons, and compared …


The Water Footprint Of Biofuel Produced From Forest Wood Residue Via A Mixed Alcohol Gasification Process, Yi-Wen Chiu, May Wu Jul 2013

The Water Footprint Of Biofuel Produced From Forest Wood Residue Via A Mixed Alcohol Gasification Process, Yi-Wen Chiu, May Wu

Natural Resources Management and Environmental Sciences

Forest residue has been proposed as a feasible candidate for cellulosic biofuels. However, the number of studies assessing its water use remains limited. This work aims to analyze the impacts of forest-based biofuel on water resources and quality by using a water footprint approach. A method established here is tailored to the production system, which includes softwood, hardwood, and short-rotation woody crops. The method is then applied to selected areas in the southeastern region of the United States to quantify the county-level water footprint of the biofuel produced via a mixed alcohol gasification process, under several logistic systems, and at …


Compressed Air Foam And Structural Firefighting Research, Christopher Dicus, Thomas Korman, Casey Grant, Steve Lohr, Dan Madrzykowski, Fred Mowrer, Chris Pascual, Dan Turner Jul 2013

Compressed Air Foam And Structural Firefighting Research, Christopher Dicus, Thomas Korman, Casey Grant, Steve Lohr, Dan Madrzykowski, Fred Mowrer, Chris Pascual, Dan Turner

Natural Resources Management and Environmental Sciences

No abstract provided.


The Burning Question: Why Is Fire Season Becoming Worse?, Christopher Dicus Jul 2013

The Burning Question: Why Is Fire Season Becoming Worse?, Christopher Dicus

Natural Resources Management and Environmental Sciences

No abstract provided.


Core-Scale Solute Transport Model Selection Using Monte Carlo Analysis, Bwalya Malama, Kristopher L. Kuhlman, Scott C. James Jun 2013

Core-Scale Solute Transport Model Selection Using Monte Carlo Analysis, Bwalya Malama, Kristopher L. Kuhlman, Scott C. James

Natural Resources Management and Environmental Sciences

Model applicability to core-scale solute transport is evaluated using breakthrough data from column experiments conducted with conservative tracers tritium and sodium-22 , and the retarding solute uranium-232 . The three models considered are single-porosity, double-porosity with single-rate mobile-immobile mass-exchange, and the multirate model, which is a deterministic model that admits the statistics of a random mobile-immobile mass-exchange rate coefficient. The experiments were conducted on intact Culebra Dolomite core samples. Previously, data were analyzed using single-porosity and double-porosity models although the Culebra Dolomite is known to possess multiple types and scales of porosity, and to exhibit multirate mobile-immobile-domain mass transfer characteristics …


Impact Of Hydraulic Fracturing On Ground And Surface Water Resources, Reyna Schenck Jun 2013

Impact Of Hydraulic Fracturing On Ground And Surface Water Resources, Reyna Schenck

Natural Resources Management and Environmental Sciences

The following study examines hydraulic fracturing operations in the United States in relation to groundwater contamination, withdrawals of freshwater resources, and jurisdictional authority over the activity with the purpose of producing objective analysis of research findings. With a growing population and increasing energy needs, hydraulic fracturing is expanding across the nation, as is public concern over the risks to freshwater resources. Because of the difficulty in identifying non-point sources of water pollution, a lack of legitimate water samples representing baseline conditions, and incomplete lists of chemical additives used, study results are often inconclusive as to the correlation between hydraulic fracturing …


Investigation Of Biochemical Biorefinery Sizing And Environmental Sustainability Impacts For Conventional Bale System And Advanced Uniform Biomass Logistics Designs, Andrew M. Argo, Eric Cd Tan, Daniel Inman, Matt H. Langholtz, Lawrence M. Eaton, Jacob J. Jacobson, Christopher T. Wright, David J. Muth Jr., May M. Wu, Yi-Wen Chiu, Robin L. Graham May 2013

Investigation Of Biochemical Biorefinery Sizing And Environmental Sustainability Impacts For Conventional Bale System And Advanced Uniform Biomass Logistics Designs, Andrew M. Argo, Eric Cd Tan, Daniel Inman, Matt H. Langholtz, Lawrence M. Eaton, Jacob J. Jacobson, Christopher T. Wright, David J. Muth Jr., May M. Wu, Yi-Wen Chiu, Robin L. Graham

Natural Resources Management and Environmental Sciences

The 2011 US Billion-Ton Update1 estimates that there are enough agricultural and forest resources to sustainably provide enough biomass to displace approximately 30% of the country’s current petroleum consumption. A portion of these resources are inaccessible at current cost targets with conventional feedstock supply systems because of their remoteness or low yields. Reliable analyses and projections of US biofuels production depend on assumptions about the supply system and biorefinery capacity, which, in turn, depend on economics, feedstock logistics, and sustainability. A cross-functional team has examined optimal combinations of advances in feedstock supply systems and biorefinery capacities with rigorous design information, …


Considering Water Availability And Wastewater Resources In The Development Of Algal Bio-Oil, Yi-Wen Chiu, May Wu Apr 2013

Considering Water Availability And Wastewater Resources In The Development Of Algal Bio-Oil, Yi-Wen Chiu, May Wu

Natural Resources Management and Environmental Sciences

This study aims to quantify water appropriation and the potential production of algal bio-oil using freshwater and municipal wastewater effluent (MWW) as an alternative water resource. The county-level analysis focuses on open-pond algae cultivation systems located in 17 states in the southern United States. Several scenarios were developed to examine the water availability for algae bio-oil production under various water resource mixing MWW and freshwater. The results of the analysis indicate that water availability can significantly affect the selection of an algal refinery site and therefore the potential production of algal bio-oil. The production of one liter of algal bio-oil …


Recognizing And Modeling Variable Drawdown Due To Evapotranspiration In A Semiarid Riparian Zone Considering Local Differences In Vegetation And Distance From A River Source, Brady Johnson, Bwalya Malama, Warren Barrash, Alejandro N. Flores Feb 2013

Recognizing And Modeling Variable Drawdown Due To Evapotranspiration In A Semiarid Riparian Zone Considering Local Differences In Vegetation And Distance From A River Source, Brady Johnson, Bwalya Malama, Warren Barrash, Alejandro N. Flores

Natural Resources Management and Environmental Sciences

Riparian zones in semiarid regions often exhibit high rates of evapotranspiration (ET) in spite of low-soil moisture content due to the presence of phreatophytic vegetation that is able to withdraw water from shallow aquifers. This work seeks to better define the relationship between ET, the saturated zone and the river boundary by comparing observed water table drawdown records to analytically modeled drawdown in fully penetrating wells of an unconfined aquifer in response to daily ET flux. ET at the Boise Hydrogeophysical Research Site (BHRS), a riparian zone in a temperate, semiarid environment, is calculated using a radiation-based method to provide …


Variability In Effect Of Climate Change On Rain-On-Snow Peak Flow Events In A Temperate Climate, Christopher G. Surfleet, Desirèe Tullos Feb 2013

Variability In Effect Of Climate Change On Rain-On-Snow Peak Flow Events In A Temperate Climate, Christopher G. Surfleet, Desirèe Tullos

Natural Resources Management and Environmental Sciences

The frequency of rain-on-snow (ROS) hydrologic events, which produce high runoff volumes and lead to large-scale flooding and avalanching, are likely to change in the future as the types and timing of precipitation change. The relationship between ROS precipitation events and peak daily flow events P1-year return were examined for historical and future runoff affected by climate change within the Santiam River Basin, Oregon. Historical streamflow records and modeled historical and future streamflow projections were analyzed for three sites across three elevation zones defined by the dominant precipitation types; rain, rain and snow transition, and snow. The results illustrate that, …


Climate Change And The Water Crisis In Israel, Lauren Deutsch Nov 2012

Climate Change And The Water Crisis In Israel, Lauren Deutsch

Natural Resources Management and Environmental Sciences

Israel’s water crisis is controlled by the availability and location of water resources that are affected by climate change and geopolitics in southwest Asia. Conflict between Israel and the Palestinian occupied territories in the Gaza Strip and the West Bank have put strains on the allocation of water recourses. The goal of this research was to model how much a change in climate will affect the amount of available freshwater in Israel. Intensive research taken from Israel and the occupied territories was carried out to understand how the amount of precipitation, rainfall, and the rate of evaporation is affected by …


Quantifying The Regional Water Footprint Of Biofuel Production By Incorporating Hydrologic Modeling, M. Wu, Y. Chiu, Y. Demissie Oct 2012

Quantifying The Regional Water Footprint Of Biofuel Production By Incorporating Hydrologic Modeling, M. Wu, Y. Chiu, Y. Demissie

Natural Resources Management and Environmental Sciences

A spatially explicit life cycle water analysis framework is proposed, in which a standardized water footprint methodology is coupled with hydrologic modeling to assess blue water, green water (rainfall), and agricultural grey water discharge in the production of biofuel feedstock at county-level resolution. Grey water is simulated via SWAT, a watershed model. Evapotranspiration (ET) estimates generated with the Penman-Monteith equation and crop parameters were verified by using remote sensing results, a satellite-imagery-derived data set, and other field measurements. Crop irrigation survey data are used to corroborate the estimate of irrigation ET. An application of the concept is presented in a …


Selection Of Hydrologic Modeling Approaches For Climate Change Assessment: A Comparison Of Model Scale And Structures, Christopher G. Surfleet, Desirèe Tullos, Heejun Chang, Il-Won Jung Sep 2012

Selection Of Hydrologic Modeling Approaches For Climate Change Assessment: A Comparison Of Model Scale And Structures, Christopher G. Surfleet, Desirèe Tullos, Heejun Chang, Il-Won Jung

Natural Resources Management and Environmental Sciences

A wide variety of approaches to hydrologic (rainfall–runoff) modeling of river basins confounds our ability to select, develop, and interpret models, particularly in the evaluation of prediction uncertainty associated with climate change assessment. To inform the model selection process, we characterized and compared three structurally-distinct approaches and spatial scales of parameterization to modeling catchment hydrology: a large-scale approach (using the VIC model; 671,000 km2 area), a basin-scale approach (using the PRMS model; 29,700 km2 area), and a site-specific approach (the GSFLOW model; 4700 km2 area) forced by the same future climate estimates. For each approach, we present …


Uncertainty In Hydrologic Modelling For Estimating Hydrologic Response Due To Climate Change (Santiam River, Oregon), Christopher G. Surfleet, Desirée Tullos Aug 2012

Uncertainty In Hydrologic Modelling For Estimating Hydrologic Response Due To Climate Change (Santiam River, Oregon), Christopher G. Surfleet, Desirée Tullos

Natural Resources Management and Environmental Sciences

This paper explores the predicted hydrologic responses associated with the compounded error of cascading global circulation model (GCM) uncertainty through hydrologic model uncertainty due to climate change. A coupled groundwater and surface water flow model (GSFLOW) was used within the differential evolution adaptive metropolis (DREAM) uncertainty approach and combined with eight GCMs to investigate uncertainties in hydrologic predictions for three subbasins of varying hydrogeology within the Santiam River basin in Oregon, USA. Predictions of future hydrology in the Santiam River include increases in runoff in the fall and winter months and decreases in runoff for the spring and summer months. …


Assessing County-Level Water Footprints Of Different Cellulosic- Biofuel Feedstock Pathways, Yi-Wen Chiu, May Wu Jul 2012

Assessing County-Level Water Footprints Of Different Cellulosic- Biofuel Feedstock Pathways, Yi-Wen Chiu, May Wu

Natural Resources Management and Environmental Sciences

While agricultural residue is considered as a near-term feedstock option for cellulosic biofuels, its sustainability must be evaluated by taking water into account. This study aims to analyze the county-level water footprint for four biofuel pathways in the United States, including bioethanol generated from corn grain, stover, wheat straw, and biodiesel from soybean. The county-level blue water footprint of ethanol from corn grain, stover, and wheat straw shows extremely wide variances with a national average of 31, 132, and 139 L of water per liter biofuel (Lw/Lbf), and standard deviation of 133, 323, and 297 L …


The Effects Of Biochar Age And Concentration On Soil Retention Of Phosphorus And Infiltration Rate, Emilie Schneider Jun 2012

The Effects Of Biochar Age And Concentration On Soil Retention Of Phosphorus And Infiltration Rate, Emilie Schneider

Natural Resources Management and Environmental Sciences

Changes in land use and land management practices are regarded as one of the main factors in altering the hydrogeological system, causing changes in runoff, surface supply yields, and the quality of receiving water (Tong and Chen, 2002). Phosphorus is a significant contributor to accelerated eutrophication of fresh water and is largely sourced from agricultural runoff (Sharpley et al., 1994). The dominant processes controlling solution composition in agricultural soils are primarily ‘chemical’ for P (i.e. adsorption/desorption and dissolution/precipitation) (Edwards and Withers, 1998). Biochar has chemical characteristics that have the potential to adsorb P or influence precipitation of P insoluble pools …


A Study Of Enhanced De-Chlorination And Bio-Remediation: Molasses Injections Into Groundwater, Brent Anderson Jun 2012

A Study Of Enhanced De-Chlorination And Bio-Remediation: Molasses Injections Into Groundwater, Brent Anderson

Natural Resources Management and Environmental Sciences

No abstract provided.