Forest Sciences Commons^™

Design And Test The Effectiveness Of Interpretive Signs Using Eye Tracking And Biometric Data, Hadara Gordon, Wendy Miyazaki

Baker/Koob Endowments Awarded Projects

Recreational trails on forested lands should satisfy the needs of recreationists, safeguard important habitats, and maintain the natural environment (Kortenkamp et al., 2021). Appropriate management is critical because of the increasing number of visitors. Signs are a cost-effective method to reduce the negative impacts on visitors and enhance visitor experiences (Brown et al., 2010). This research aimed to investigate how visitors pay attention to signs, view the trail surrounded by trees and behave in a natural space.

Automated Tree Mortality Detection Using Ubiquitously Available Public Data, Michael T. Huggins

Master's Theses

Understanding the dynamic interplay between fire severity, topography, and tree mortality, is crucial for predicting future forest dynamics and enhancing resilience against climate change-induced wildfire regimes. This thesis develops a multi-sensor approach for automated estimation of tree mortality, then applies it to examine trends in tree mortality over a six-year period across a fire affected study site in the Trinity River basin in Northern California. The Random Forest model uses publicly available USGS 3D Elevation Program Lidar (3DEP) and NAIP imagery as inputs and is likely to be easily adaptable to other landscapes. The model had a Receiver Operating Characteristic …

Fire Effects On Soil Organic Matter In The Creek Fire, Gracie E. Doolin

Master of Science in Environmental Sciences and Management Projects

Wildfires have increased in frequency and severity over the past few decades due to the increased concertation of CO2 emissions from anthropogenic influence. Soil carbon (C) sequestration has been identified as a climate change mitigation strategy; however, the influx of large-scale wildfires has accelerated landscape processes such as erosion, reducing soil aggradation, and soil C and nitrogen (N) protection. This trend is highlighted by the Creek Fire that occurred in September 2020 and burned 379,895 acres in the Sierra National Forest. This research is designed to close the knowledge gap regarding the impact of burn severity on soil organic matter …

Analysis And Installation Of A Demonstration Agroforestry Orchard For Californian Mediterranean Plant Communities, Brandon Hurd

Master of Science in Environmental Sciences and Management Projects

Climate-appropriate agroforestry can provide low-input food security and ecosystem services for local Californian Mediterranean climates, while conserving natural resources (e.g., water, nitrogen, etc.). This project showcases a variety of agroforestry methods for five common plant communities of California and other analogous Mediterranean climates at the CAFES Experimental Farm on the campus of Cal Poly San Luis Obispo. Plant community species and their ethnobotanical uses were analyzed to mimic and incorporate aspects of native flora. Agricultural plants were also characterized to represent each of the five selected plant communities. GIS was used to assess the project site for soil, slope, and …

Post-Fire Erosion Following The Czu Lightning Complex Fire: Quantifying Hillslope Erosion And Providing Guidance Towards Improving Post-Fire Response, Matthew C. Crockett, Matthew Crockett

Master of Science in Environmental Sciences and Management Projects

The size and severity of wildfires have increased in California during recent decades. This trend is highlighted through the CZU Lightning Complex fire of August 2020 which burned over 86,000 acres in the Santa Cruz mountains of California. The fire greatly impacted the Little Creek watershed, a roughly 1,300 acre watershed that exists largely within Cal Poly San Luis Obispo’s Swanton Pacific Ranch (SPR). The current trends of California’s increased wildfire regime are expected to continue, raising concerns regarding the direct and secondary effects on forest watersheds and the effectiveness of current post-fire erosion control management. Accelerated rates of erosion …

Efficacy Of Chemical And Biological Stump Treatments For The Control Of Heterobasidion Occidentale Infection Of California Abies Concolor, Adrian Luis Poloni

Master's Theses

We conducted an experimental evaluation of treatments to limit Heterobasidion occidentale infection of white fir (Abies concolor) stumps and wounds in California mixed conifer forests. We tested the efficacy of urea, borate, and a mixture of two locally collected Phlebiopsis gigantea strains in preventing pathogen colonization of fir stumps and separately, urea and borate as infection controls on experimental stem wounds. These were paired with a laboratory test on ~100 g wood blocks with and without a one-week delay between inoculation and treatment. Urea, borates, and Phlebiopsis treatments all significantly reduced the stump surface area that was colonized …

Estimating And Modeling Transpiration Of A Mountain Meadow Encroached By Conifers Using Sap Flow Measurements, Simon Joseph Marks

Master's Theses

Mountain meadows in the western USA are experiencing increased rates of conifer encroachment due to climate change and land management practices. Past research has focused on conifer removal as a meadow restoration strategy, but there has been limited work on conifer transpiration in a pre-restoration state. Meadow restoration by conifer removal has the primary goal of recovering sufficient growing season soil moisture necessary for endemic, herbaceous meadow vegetation. Therefore, conifer water use represents an important hydrologic output toward evaluating the efficacy of this active management approach. This study quantified and evaluated transpiration of encroached conifers in a mountain meadow using …

Pitch Canker In The Año Nuevo Monterey Pine Stand: A Retrospective Analysis, Davis Harrison

Master of Science in Environmental Sciences and Management Projects

Monterey pine (Pinus radiata) is a closed cone conifer tree native to California. Although it is an ecologically and economically valuable tree, there are only five remaining native populations, including, the Año Nuevo stand along California’s central coast. All the remaining native populations have faced threats to their survival, none more than the non-native disease pitch canker (Fusarium circinatum). This fungal infection causes lesions, dead branches, tree top death, and can be potentially fatal to infected trees. This paper is a continuation of a study beginning in 2001, aimed at evaluating the impact of silvicultural management practices on pitch canker …

Post-Czu Lightning Complex Regeneration In The Año Nuevo Monterey Pine Stand, Allison Trutna

Master of Science in Environmental Sciences and Management Projects

Climate induced increases in fire frequency and severity along with years of fire suppression and drought are predicted for California. The recent CZU Lightning Complex, a high severity wildfire, burned in the Santa Cruz Mountains on California’s central coast and affected an assortment of vegetation, including the survival and recovery of the native Año Nuevo Monterey pine (Pinus radiata (D. Don)) stand. This stand is partially located in Cal Poly’s Swanton Pacific Ranch and has been monitored for over 20 years for the presence of pitch canker (Fusarium circinatum) fungal disease. This study characterized the survival and initial recovery of …

Fuel Inventory Report For Montana De Oro State Park, Spencer Gordon

Master of Science in Environmental Sciences and Management Projects

Within the last century anthropogenic effects have shifted fire resilient habitats that are adapted to thousands of years of frequent low intensity fires to landscapes that are susceptible to extreme fire behavior which threaten human assets and sensitive natural resources. Entities that manage forests will need to prioritize fuel reduction as a management tool to promote forest health and mitigate hazardous fire conditions. A fuel inventory of a eucalyptus forest at Montana De Oro State Park in Los Osos, CA was collected using a combination of Brown’s 1973 and Brown’s 1982 methods. The fuel inventory revealed the eucalyptus forest yielded …

Soil Disturbance In Sierra Nevada Montane Meadow Following Lodgepole Pine Removal, Nicholas Cary

Master of Science in Environmental Sciences and Management Projects

Climate change and other anthropogenic stressors are driving conifer encroachment into meadow habitat. Encroachment, if ignored, can revert meadows back into dense forested habitat, negating meadow’s ecologic services (Durak et al. 2014). This research attempts to measure soil and stream habitat disturbances in Rock Creek meadow, located with Collins Pine Company land in Plumas County, California after clear-cut removal of encroaching lodgepole pine with mechanical machinery. Soil bulk density, ground cover transect data, and stream habitat conditions were monitored before (July 2019) and after (June 2021) restoration to measure changes in soil compaction, stream temperature, and surface disturbance (rutting/ tracks). …

Will Oakland Burn Again: Understanding The Fire Hazard In An Urban Park System, Alessandra M. Zambrano

Master's Theses

Though almost thirty years have passed since the 1991 Tunnel Fire, the wildfire hazard is still present in the Oakland Hills. This study was conducted to determine if the vegetation in the Oakland Hills had reverted back to fuel conditions that contributed to the Tunnel Fire, examine how the fire hazard has changed since 1991, and evaluate planned wildfire mitigation. The goal was to determine how fuel conditions have changed since 1991 and compare potential fire behavior to that of the Tunnel Fire. Additionally, the study examined the effectiveness of the mitigation actions described in the East Bay Regional Park …

Early Wildfire Detection With Line Sensors, Virginia Yan

Master's Theses

Over the last few years, wildfires have become more devastating to communities as the fires are inevitably destructive to many homes, businesses, and ecosystems. Frequent wildfires also pose a significant threat to power grids and nearby residents as they can damage transmission lines and other electrical equipment, which in turn can cause major power shutdowns. Especially in western U.S., severe drought conditions and weather variability cause residents to become more vulnerable to wildfire disasters as their safety is threatened. We are incompetent to control the wildfires effectively despite existing advanced technologies. Hence, an algorithm based on energy conservation and heat …

The Water Table, Soil Moisture And Evapotranspiration Conditions Following The Removal Of Conifers From Two Encroached Meadows, Tyler J. Davis

Master's Theses

Montane meadows provide essential habitat for a variety of unique species and important ecosystem services in the western United States. Although important, meadows have experienced increased rates of conifer encroachment due to climate change, fire suppression and grazing. To combat meadow degradation from conifer encroachment, land managers have employed various restoration strategies one of which is conifer removal. Multiple studies have investigated the relationship between meadow hydrology and vegetation; however, few have assessed the effect of conifer removal on meadow groundwater. The goal of this study is to determine if the removal of conifers from an encroached meadow has an …

An Analysis Of Changes In Stream Temperature Due To Forest Harvest Practices Using Dhsvm-Rbm, Julia B. Ridgeway

Master's Theses

Forest harvesting has been shown to cause various changes in water quantity and water quality parameters, highlighting the need for comprehensive forest practice rules. Studies show a myriad of impacts to ecosystems as a result of watershed level changes, such as forest harvesting. Being able to better understand the impact that forest harvesting can have on stream temperature is especially critical in locations where federally threatened or endangered fish species are located. The overall goal of this research project is to assess responses in stream temperature to various riparian and forest harvest treatments in a maritime, mountainous environment. The results …

Quantifying The Environmental Performance Of A Stream Habitat Improvement Project, Cody Morse

Master's Theses

River restoration projects are being installed worldwide to rehabilitate degraded river habitat. Many of these projects focus on stream habitat improvement (SHI), and an estimated 60%of the 37,000 projects listed in the National River Restoration Science Synthesis Program focus on SHI for salmon and trout species. These projects frequently lack a sufficient monitoring program or account for the environmental costs associated with SHI. The present study used life cycle assessment (LCA) techniques and topographic effectiveness monitoring to quantify environmental costs on the basis of geomorphic change. This methodology was a novel approach to assessing the cost-benefit relationship of SHI. To …

Forest Densification Over 85 Years In A Sierra Nevada Mixed-Conifer Forest Decreases Conifer Regeneration And Limits Survival, Marissa A. Vossmer

Master's Theses

Forest densification in response to a century of fire suppression in Sierra Nevada mixed conifer forests has decreased conifer regeneration and survival. Increases in overstory biomass and decreases in canopy heterogeneity, along with decreases in shrub cover in the understory, has created unfavorable establishment site conditions for conifer species. Establishment site conditions are key in promoting germination and establishment of conifers seeds and in determining the survival of these seedlings into the overstory. These changes in establishment site suitability resulting from the removal of disturbance from these forests has decreased conifer regeneration and survival into other age classes. In Sierra …

Citizen Science Sensor Development - Smap | Soil Moisture Active Passive, Hagop Hovhannesian

STAR Program Research Presentations

“Detailed monitoring of soil moisture provides a view of how our whole Earth system works.”

The Soil Moisture Active Passive (SMAP) satellite mission was launched in January 2015; its main purpose is to acquire global measurements of soil moisture. SMAP partnered with the GLOBE program (Global Learning and Observations to Benefit the Environment), which is an international program where students collect environmental variables in a scientifically methodical way. SMAP readings and maps have various uses in various fields, which include monitoring drought, predicting floods, assisting in crop productivity, and linking water, energy and carbon cycles. The goal of this project …

Evaluating The Myth Of Allelopathy In California Blue Gum Plantations, Kristen Marie Nelson

Master's Theses

It is widely accepted that allelopathy is not only significant, but more or less singular, in the inhibition of understory vegetation in California Eucalyptus globulus (blue gum) plantations. However, there is no published documentation of allelopathy by blue gums against California native species. Here, we present evidence that germination and early seedling growth of five California native species are not inhibited by chemical extracts of blue gum foliage, either at naturally-occurring or artificially concentrated levels. In the greenhouse, seeds were germinated in field-collected soil from mature blue gum plantations and the adjacent native, coastal scrub communities. In petri plates, seeds …

The Effect Of Drought On Stomatal Conductance In The Biosphere 2 Rainforest, Justin Gay, Joost Van Haren

STAR Program Research Presentations

Drought is a major climate change concern for the Earth’s rainforests; however little is currently known about how these forests and individual plants will respond to water stress. At the individual level, the ability of plants to regulate their stomatal conductance is an important preservation mechanism that helps to cool leaves, regulate water loss, and uptake carbon dioxide. At the ecosystem level, transpiration in rain forests is a major contributor to the feedback loop that returns moisture to the atmosphere for continued rains. Nearly 60% of atmospheric moisture in the Amazon rain forests has been traced back to origins of …

Radiocarbon Isotopic Classification Of Deep Tropical Forest Soils, Brooke Butler, Karis J. Mcfarlane, Jennifer Pett-Ridge, Katherine A. Heckman

STAR Program Research Presentations

Tropical forest soils have an important role in global carbon (C) stocks. Small changes in the cycling of C could drastically affect atmospheric carbon dioxide (CO2) concentrations and active cycling of carbon in a forest community. Currently, little is understood of how tropical forest soils will respond to the increasing global temperatures. To examine the effects of warming/ drought on losses of older versus younger soil C pools, we implemented radiocarbon (14C) isotopic characterization of various soil plot samples and depths from the Luquillo Experimental Forest, Puerto Rico. 14C was measured using Accelerated Mass Spectrometry (AMS) from catalytically condensed carbon …

Evaluating Five Years Of Soil Hydrologic Response Following The 2009 Lockheed Fire In The Coastal Santa Cruz Mountains Of California, Mary Theresa Crable

Master's Theses

The Lockheed Fire burned 31 km² (7,660 acres) of the Scotts Creek watershed in August 2009. 4.5 km² (1,100 acres) of California Polytechnic State University’s educational and research facility at Swanton Pacific Ranch. The burned region presented an opportunity for studying the hydrologic response of burned soils in the Santa Cruz Mountains where there is insufficient post-fire studies regarding fire-effects on watershed processes such as infiltration and near-surface runoff. Soil infiltration and soil water repellency were evaluated with rainfall simulations, Mini-disk Infiltrometer (MDI) and water drop penetration time tests (WDPT) at sites represented by variations in burn severity, …

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 …

Evaluation Of Red Alder Mortality In The Little Creek Watershed Following The 2009 Lockheed Fire, Dylan Robert Theobald

Master's Theses

Five hundred eighty red alder along a 2.16 km portion of the Little Creek riparian zone were assessed for mortality following the 2009 Lockheed Fire near Davenport, California. The study area was divided into burn severity zones and every red alder within the riparian zone was observed and assessed for mortality. Height, diameter at breast height (DBH), and age were collected on selected trees. An estimation of red alder large woody debris (LWD) input to Little Creek since a 2010 LWD survey (Smith, 2010) was calculated using average red alder tree dimensions applied to Smalian’s formula (MLNRO, 2011). The mean …

Land Management Practices And Their Effects On Grouse Populations Of The American Pacific Northwest, Connor Michael Pompa

Natural Resources Management and Environmental Sciences

No abstract provided.

The Imperative Of Conserving California's Foothill Oak Woodlands, Lauren Phillips

Social Sciences

No abstract provided.

Variability In Soil Climate And Respiration On Managed Timber Stands: A Case Study In Southwest Oregon, Scott Pensky, Adrian Gallo

Natural Resources Management and Environmental Sciences

Thinning of forested lands and timber stands in the Pacific Northwest have taken place for centuries with a limited understanding of how the alterations may affect ecosystem functions. The goal of this study was to examine the soil climate and microbial activity on a seasonal timescale of thinning practices examined at different stages of succession. Two timber stands in Southwestern Oregon within the Grayback Creek Watershed were chosen because of identical forest management techniques separated by a 10-year treatment interval (40% variable density thinning). Field methods and equipment measured canopy coverage, soil moisture and temperature at 3 depths (5, 15, …

Habitat Type Mapping In Montana De Oro State Park Through Gis Image Classification, Evan Corrales, Sarah Fockler

Natural Resources Management and Environmental Sciences

This project involved using aerial imagery and GIS procedures to automatically map the basic vegetation communities present within Montana de Oro State Park, CA: grassland, coastal scrub, bare ground, woodland, and riparian areas. 1m resolution color imagery of the park from the NAIP 2005 (National Agriculture Inventory Program) and 1m resolution LiDAR height data were also used to determine the locations of the different vegetation types in the park. This data was then classified by color using the interactive supervised classification tool in ArcGIS. Points were taken in the park using a GPS unit, and compared with the GIS results …

Post-Fire Response Of Little Creek Watershed: Evaluation Of Change In Sediment Production And Suspended Sediment Transport, Andrew Wood Loganbill

Master's Theses

The Little Creek watershed was assessed to identify changes in event-based suspended sediment export and determine the factors contributing to sediment production the first year following the Lockheed Fire in 2009. The amount and volume of near-stream sediment sources were found to decrease, while an increase in hillslope sediment production was documented. High intensity, short duration rainfall (up to 87 mm/hr for 10 minute duration) initiated extensive rilling and minor channel-derived debris torrents originating from the upper south facing slopes. Rainfall simulations, hillslope erosion plots, and soil infiltration tests indicated that fire produced soil water repellency, the lack of ground …

Mortality Assessment Of Redwood And Mixed Conifer Forest Types In Santa Cruz County Following Wildfire, Steve R. Auten

Master's Theses

On August 12, 2009, the Lockheed Fire ignited the west slope of the Santa Cruz Mountains burning approximately 7,819 acres. Foresters and other land managers were left with challenging decisions on how to evaluate tree mortality. Big Creek Lumber Company, California Polytechnic State University, San Luis Obispo (Cal Poly)’s Swanton Pacific Ranch (SPR), and other resource professionals familiar with this region teamed up to develop a method for evaluating damage and thereby mortality for redwood, California nutmeg, live oak, tanoak, California bay, Pacific madrone, big leaf maple, Douglas-fir, Monterey pine, and knobcone pine. Quantitative damage criteria were used to design …