This thesis has two data chapters that consider factors affecting loblolly pine health in localized regions of Mississippi. The first data chapter investigated the abiotic and biotic factors contributing to loblolly pine (Pinus taeda) mortality on private timberland in Mississippi. This assessment considered temperature and precipitation variations, bark beetle populations, foliar and root pathogen tests, and drone survey. The results revealed that the loblolly pine mortality resulted from combination of factors. The second data chapter examined the impact of habitat fragmentation on southern pine beetle (SPB; Dendroctonus frontalis) infestation in Homochitto National Forest (HNF). This was assessed through remote sensing and categorization of SPB spots in HNF over nine years. Results indicated that increased total pine patch area, decreased distance between pine patches, and low patch diversity are important drivers of SPB outbreak in HNF. These results can help improve loblolly pine health and management in the southeastern United States.

Spruce-Fir forests are relicts from the Pleistocene and can only be found within the Southern Appalachians. Analyzing the relationships between species distribution, climatic parameters, topography, and biotic interactions through ecological niche modeling creates prediction maps for conservation efforts. Maxent, Boosted Regression, and Random Forest were utilized to compare which model and variable combinations best approximate the unique mountain forest environment. Maxent with a bias file produced optimal results and was used to examine distributional changes that may occur in the future and how these changes compare to paleo-environmental distributions. Fraser fir has shown evidence of being influenced by changing climates based on historical data and in future predictions. These findings show areas of decline in 2050 and 2070. When combined with weather, climate, genetics, and ecological studies, this is a useful tool for resource allocation to areas that are predicted to be resilient in the face of climate change.

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 Area Under the Curve (ROC AUC) score in training of 0.998. In multiple rounds of validation, using geographically distinct sets of holdout data, had mean accuracy of 0.998. The trained model was then used to assess tree mortality across a patchwork of different levels of burn severity at a site in Northern California. When applied to the study site significant variations were found in tree mortality across different fire severity treatments and landforms. This model shows potential for incorporation into predictive tree mortality models based on landform and climate.

The majority of the forested land in New England is owned by private landowners, a large number of whom are at or above retirement age. In the coming decades these landowners are going to be making decisions about what happens to their land once they no longer own it. Female landowners specifically play a critical role in the long-term planning and decision-making process. Women generally have a longer life expectancy than men and assess their level of confidence and financial stability in ways that differ from men. This difference in perception influences the decisions they make about their land. Despite this, little is known about decisions female landowners are making and barriers they face to formulating informed decisions that are in line with their goals. In order to understand more about female landowners’ estate planning objectives, I conducted a mixed-methods study. Through a mail survey and subsequent qualitative interviews, I found that women were more likely than men to have lower confidence confidence in moving forward with plans for the land, lower certainty that their financial resources were adequate to move forward, and less certainty when it came to future decisions about their land. However, women who were certain about their estate planning objectives were more likely than men to have a conservation-based decision. The results of this mixed-methods study are applied to peer-to-peer network events and outcomes are discussed.

Wastewater application to land can be a useful tool for mitigating impacts of nutrient enrichment on aquatic systems. A land application treatment system at VCU’s Rice Rivers Center in Charles City County, VA provided an opportunity to study the impact of wastewater addition on the biogeochemistry of forests representative of the Mid-Atlantic Coastal Plain. Nutrient concentrations in throughfall and leachate were measured at Treatment and Control sites to assess differences in nutrient deposition and retention. Wastewater amended plots from the Walter L. Rice education building received 20-fold (N) and 6-fold (P) higher inputs relative to Control plots and plots located at the Virginia Department of Game and Inland Fisheries building. Despite higher inputs, leaching losses of P from the Rice Treatment plots were comparable to Control plots, indicating that the land-based application system effectively mitigated wastewater loads. Leaching losses of nitrate were two-fold higher from Treatment plots relative to Controls, suggesting a potential N saturation effect and a reduction in N retention capacity of the treated forest. Nitrogen effects on vegetation were indicated by lower root biomass and greater root N content among Treatment plots relative to Control plots. Overall, these results suggest that wastewater–amended plots near the Rice education building receive appreciably higher nutrient inputs and could, therefore, serve as a model system for assessing effects on forest ecosystems.

Street trees are an important component of the urban forest that can provide direct and indirect benefits to social and ecological sustainability in cities. Temporal and spatial interactions between human and non-human management agents determine the distribution and health of street tree populations in urban areas. This dissertation seeks to enhance our understanding of the spatial patterns and processes affecting street trees by investigating the agents and social-ecological determinants of changes to street tree distributions in urban residential neighborhoods. The research was guided by three primary questions: (1) Are recent changes to the spatial distribution of street trees influenced by socio-demographic household and neighborhood characteristics? (2) Which management agents are the strongest predictors of recent changes to street tree distributions and does the contribution of these agents vary in relationship to social-ecological patterns within a city? (3) To what extent are household street tree management decisions related to the built and bioecological material characteristics of the public right-of-way? These questions were investigated in a case study that examined street tree management and public right-of-way (PROW) canopy change associated with single-family residential areas in and near the City of Tampa, Florida. The methodological approach employed a multi-method design using a conceptual framework developed to capture the complexity of management within human ecosystems. Urban remote sensing and spatial analytical techniques were used to examine the geographic association between patterns of street tree change and socio-demographic characteristics. Household survey techniques were utilized to examine the determinants of street tree management; specifically planting, removal, and trimming. Interviews with key informants familiar with urban forest management provided additional insights to complement the location specific knowledge of household survey respondents. Street tree change was examined for the period of 2003 to 2006, and information about household management actions also included recent years (i.e., 2009-2011). A citywide pattern of street tree increases was disproportionately distributed with respect to socioeconomic status; with greater increases in affluent neighborhoods. Patterns of change within local portions of the study area revealed significant and spatially variable relationships with socioeconomic status, as well as race/ethnicity variables and indicators of lifestyle differences. The findings suggest that the citywide pattern of change associated with socioeconomic status may perpetuate an inequitable outcome in the distribution of street trees at the expense of less affluent neighborhoods. The local patterns of change indicate that the processes driving street tree distributions may also reflect differences in attitudes toward trees. The case study did not find sufficient evidence to link the actions of individual agents with street tree change. Street tree increases were more likely in areas where tree trimming had been reported and where property market values were greater, but less likely in PROW segments with overhead power lines. Households, public agencies and builders, but not neighborhoods, were the primary human street tree management agents. Past and ongoing land development and redevelopment decisions, including the configuration of PROW infrastructures, may be one of the most important factors affecting patterns of street tree change. Landscape decisions and practices influenced by household and neighborhood group dynamics also appear to be important factors affecting street tree change. Damages caused by storm event and differences in tree species lifecycle characteristics represent important non-human agents of street tree change. The findings indicated that public agencies are not the only managers of street trees and household tree management does not stop at the boundary of private property. There was no evidence of a relationship between household management actions and the material conditions of the PROW. However, there was a relationship between the presence of either power lines or sidewalks and household survey responses about who should bear responsibility for street tree management and the liability. Household respondents expressed an increased sense of personal responsibility for street tree management when a sidewalk was in front of their home. This dissertation addressed an important gap in understanding about the factors driving street tree change. Planting, removal, and trimming of street trees in Tampa is a shared responsibility with complex spatial patterns and multi-scalar drivers. An important conclusion is that the sustainability of street tree populations within the urban forest will require urban planners and managers to better understand how these management agents cooperate if they are to promote healthy, safe and beneficial street tree populations as a part of the urban forest.

One of the primary concerns associated with timber harvesting is the production of sediments from stream crossings. While research has shown that using improved haul road crossings can mitigate sediment production in perennial streams compared to the use of unimproved crossings little research has been undertaken on temporary skidder crossings of headwater streams, a situation common to a significant percentage of ground skidding operations. This experiment consisted of a controlled replicated testing of the effectiveness of four types of temporary skidder stream crossings (unimproved ford, corrugated culvert, wood panel skidder bridge, and PVC pipe bundle) relative to bedload and suspended sediment production. Automated samplers were used to monitor sediment and bedload production during the construction, use, removal, and post-removal phases associated with the use of these temporary crossings. Results showed that elevated crossings mitigated total sediment production compared to unimproved fords. Further, wood panel bridges yielded lower amounts of sediment than culverts but PVC pipe bundles show no difference between bridges or culverts. Sediment production varied by crossing type and use phase. While no differences were found among crossings types during construction, there was a difference between improved crossings and fords during use. Further, bridges and PVC pipe bundle crossings produced significantly less sediments than culverts during both their removal and during post-removal sampling and fords produced the largest amount of sediments during these phases.

Runoff from livestock operations may contain a variety of pathogens and high levels of nutrients and other harmful contaminants, and is of particular concern in central Kentucky as watersheds are threatened by waste generated from a high concentration of equine activity. Rain gardens are a type of stormwater management tool used to capture and passively treat runoff. This project aimed to incorporate rain gardens into the horse muck storage structures at a thoroughbred facility in the Canr Run watershed in Lexington, Kentucky. Water quality data from soil water within two rain garden muck pads and two control pads, and grab samples from the stream were compared. No significant differences were observed, but trends revealed higher levels of nitrate and phosphate in rain gardens compared to controls, while total organic carbon and E. coli levels were lower in the rain gardens, suggesting that the rain gardens are trapping nutrients while reducing organic matter and killing bacteria. E. coli populations were lower in stream sample locations near rain garden muck pads compared to further downstream near controls. Management recommendations include further improvement of muck storage structures, replacing old muck pads, and changing management and housekeeping habits and attitudes towards environmental responsibility.

Sequestering carbon in standing biomass, using woody bioenergy, and using woody products are the three potential ways to utilize forests in reducing greenhouse gases (GHGs) and mitigating climate change. These forestry related strategies are, however, greatly influenced by the existing markets and market based policies. This study focuses on the first two forest strategies. It investigates the combined impact of carbon and woody bioenergy markets on two different types of forests in the US – oak dominated mixed hardwood forests in the Central Hardwood Forests Region and loblolly pine forests in the southeastern US. A modification of the Harman model was used for the economic analysis of carbon sequestration and harvesting woody biomass for bioenergy. A forest carbon life-cycle assessment was used to determine the carbon emissions associated with management of forests and harvesting of wood products. Results from this study indicate that carbon payments and woody bioenergy production increase the land expectation value (LEV) for both forest types.

The fundamental physics governing wildland fire spread are still largely misunderstood. This thesis was motivated by the need to better understand the role of radiative and convective heat transfer in the ignition and spread of wildland fires. The focus of this work incorporated the use of infrared thermographic imaging techniques to investigate fuel particle response from three different heating sources: convective dominated heating from an air torch, radiative dominated heating from a crib fire, and an advancing flame front in a laboratory wind tunnel test. The series of experiments demonstrated the uniqueness and valuable characteristics of infrared thermography to reveal the hidden nature of heat transfer and combustion aspects which are taking place in the condensed phase of wildland fuelbeds. In addition, infrared thermal image-based temperature history and ignition behavior of engineered cardboard fuel elements subjected to convective and radiative heating supported experimental findings that millimeter diameter pine needles cannot be ignited by radiation alone even under long duration fire generated radiant heating. Finally, fuel characterization using infrared thermography provided a better understanding of the condensed phase fuel pyrolysis and heat transfer mechanisms governing the response of wildland fuel particles to an advancing flame front.