Landscape change affects the distribution of wildlife and represents a conservation concern, especially in Asia, which is experiencing rapid development. In Mongolia, mining, livestock grazing, infrastructure development and climate change represent major drivers of change that will impact habitats and few tools exist to predict how wildlife will respond. I examined the impacts of landscape change on the corsac fox (Vulpes corsac) in a steppe region of Mongolia. The corsac fox occurs widely throughout northern Asia, but has experienced declines in many regions and remains one the least studied canids. I addressed two questions: 1) how do common features of a landscape, such as habitats, topography, herder camps, and roads, shape the distribution of the species? and 2) how will changes in those features affect distribution in the future? I collected locations of foxes from radio-collared animals, scat surveys, and opportunistic sightings in Ikh Nart Nature Reserve, then used maximum likelihood methods and model selection techniques to develop a model that predicts occupancy probability. I then applied the model to simulations of landscape change. I collected 1,965 locations and examined 19 candidate models. The model with the most support indicated that occupancy is best described by the additive combination of shrublands, open plains, tall grasslands, and rocky habitat. Models with other covariates (camps, roads, and ruggedness) had little support. A Receiver-Operator-Characteristic plot of model performance had an Area Under the Curve of 77%, indicating that the model predicted occupancy better than expected by chance. Average occupancy across the reserve was 22% under current conditions. Incremental reductions in shrubland, open plains, and tall vegetation resulted in occupancy declines with average occupancy being 7%, 13%, and 14%, respectively, when these habitats were completely absent. The loss of all three habitats due to the desertification of the landscape through climate change resulted in an average occupancy of 7%. The results provide the first model of corsac fox occupancy, which can be used to quantitatively examine distribution and impacts of change in other parts of the species' range. In Ikh Nart, results suggest that climate change poses the greatest threat to the species as it is expected to reduce high quality habitats and confine corsac foxes to areas with high competition from red foxes.

Agricultural landscapes provide our society with many benefits. While food production is the primary role of these landscapes, sociocultural and ecological benefits are also provided. However, the full scope of benefits that we obtain from agricultural landscapes are not always taken into account, and with the intensification of agricultural activities, more complex multifunctional landscapes are converted into simpler and less-functional landscapes. I used a heterogeneous agricultural landscape, the Champlain Valley of Vermont, as a case study to examine the interactions between landscape structure and the provision of landscape functions and services. I analyzed sociocultural and production functions indices obtained via standardized landowner surveys, and ecological function indices collected in the field for 51 plots. Plots were clustered into landscape composition categories (forest, mixed and agriculture), and configuration categories (simple and complex). I identified a tradeoff between the production and ecological function in agricultural landscapes. When a rural landscape was managed for intensive agricultural production, ecological benefits decreased. Landscapes with diversified land use/land cover and heterogeneously distributed elements returned the greatest number of benefits. Agricultural areas that comprise between 30 and 45% of the landscape can prevent the loss of ecological benefits while retaining high production. I evaluated the importance of treed habitats in agricultural landscapes in maintaining biodiversity. I related landscape metrics to ecological function indices obtained from fine-grained land use/land cover maps. Metrics obtained from fine-grained maps more accurately predicted the abundance of edge tolerant birds than those obtained from coarse grained maps. I also explored the importance of small treed landscape elements for common breeding birds and evaluated the convenience of monitoring nests comparing temperature loggers to direct observations. More heterogeneous landscapes, rich in small treed elements, supported a greater density of nests. Nests located on small treed elements in agricultural landscapes were as successful as nests located in large landscape elements. These analyses deepen our knowledge about the relationship between landscape structure and function, facilitating the evaluation of the functionality of heterogeneous agricultural landscapes.

Quantifying effectiveness of soil management practices on surface and subsurface water quality at the field scale is becoming increasingly important in the Lake Champlain Basin and other agricultural watersheds. During 2012 and 2013, field plots (22.9 x 45.7 m) were established at the Lake Alice Wildlife Area in Chazy, NY to begin a long-term water quality monitoring study. Plots were established in a cool season grass field (1 ha) leased and managed by the William H. Miner Agricultural Research Institute in Chazy, NY. The soil type transitions from an excessively drained outwash soil on the upslope to a very poorly drained silty clay series at the toeslope. Tile drainage lines were installed in each plot and drained to concrete manholes at the corner of each plot where water was sampled and measured. Plots were randomly assigned to a tile-drained (TD) or naturally-drained treatment (UD). Tile outlets were plugged in the UD treatment to enable natural drainage conditions. Surface runoff water was collected at the lower boundary of each plot by shallow PVC-lined trenches that outlet to the manholes. Continuous water flow from each hydrologic pathway was measured in 5-gallon buckets with v-notch weirs and pressure transducers. Total phosphorus (TP), soluble reactive phosphorus SRP), unreactive phosphorus (UP) and sediment (TSS) loads were estimated by multiplying the mean hourly runoff volume by the respective sample concentration for each hydrologic pathway. Data were collected April 21, 2014 through June 30, 2015. Loading rates were unable to be calculated from February 22, 2015 through April 9, 2015 due to freeze/thaw cycles preventing accurate water flow data collection. Event-based loading for TP, SRP, UP, TSS, and water yield were calculated in addition to cumulative losses over the study duration. No significant differences in cumulative TP exports were found between treatments (UD = 230.9 g ha-1; TD = 233.9 g ha-1). Approximately 55% more SRP and 158% more TSS was exported by UD (130.8 g ha-1; 168.8 kg ha-1) than TD (84.2 g ha-1; 65.5 kg ha-1). Unreactive P exports from TD (149.7 g ha-1) were 50% greater than UD (100.1 g ha-1). Two runoff events dominated the treatment response. An intense rain storm on May 16, 2014 generated the greatest sediment losses in both treatments during an individual event, contributing 65 and 67% of the cumulative losses from TD and UD, respectively. This event was also responsible for 40% of UP losses from TD. A 3 d rain/snowmelt event beginning on December 24, 2014 resulted in 61 and 84% of all SRP losses for TD and UD, respectively. The results of this study indicate that tile drainage may not have a negative impact on water quality relative to a naturally drained field. However, additional years of data are needed to develop more robust conclusions as different management strategies and weather conditions could result in different outcomes.

Erosion, a surface process, can be quantified over long-term (assumed to be the natural erosion rate of the landscape) and contemporary (modern) timeframes. My research used the rare cosmogenic isotope 10Be in sand and cobbles collected from rivers in southeastern Brazil (Santa Catarina and Rio de Janeiro states) and southwestern China (Yunnan province) to quantify long-term, background rates of erosion and sediment supply. These measurements will also increase number of such measurements in tropical and subtropical climates. I assessed the relationship between landscape parameters (topographic and climatic) and background erosion rates in order to understand factors related to erosion. My data from so far unsampled states in Brazil shows that background erosion rates range between 13 and 90 m/Myr. I found that mean basin slope (R2=0.73) and mean annual precipitation (R2=0.57) are strongly correlated to erosion rates. Steep, escarpment-draining basins in Brazil erode faster than lower gradient basins draining the highlands. Comparing the isotopic concentration of river sand and cobbles, my data show that these grain sizes are sourced from different parts of the landscape. I compiled all published Brazilian cosmogenic 10Be data, and compared them to erosion rates from similar tectonic settings. While the erosion rates in Brazil are relatively low, they are similar to those in southeastern North America, but faster than rates measured on escarpments in southern Africa. In China, I tested the human effects on denudation by comparing long-term erosion rates derived from in-situ 10Be concentration and the modern sediment yield of 22 watersheds in Yunnan. Background erosion rates range between 17 and 386 m/Myr; long term sediment yields based on these erosion rates range from 79 to 893 tons km-2 yr-1. Modern sediment yields range from 90 to 2,879 tons km-2 yr-1 (data from Schmidt et al., 2011). In most watersheds, the modern sediment yield is 2-3X higher than long-term rates, likely the effect of a long history of land use in Yunnan. I found a statistically significant, positive relationship between erosion rates and both area (R2 = 0.60) and mean basin slope (R2 = 0.42). There is a negative but strong relationship between erosion rates and precipitation in my dataset (R2 = 0.60). I sampled some places where 10Be samples had been collected before to test the methodological assumption of time-invariant 10Be concentration. Concentrations generally agree on samples taken 6 months apart and in samples from the active channel and from floodplains, but not in samples collected a decade and centuries apart.

National parks have famously been called "America's best idea" and preserve the nation's natural and cultural resources for the enjoyment of all. One of the current working priorities of the National Park Service (NPS) is enhancing the relevancy and engagement of the national parks with diverse audiences, especially for underserved groups. To address this priority, transportation is needed to provide access to national parks, but transportation may not be equally accessible to all groups in society. Understanding the effects of transportation on visitation to the national parks by racial/ethnic groups is essential for the NPS to improve the accessibility of transportation systems and encourage greater visitation by racial/ethnic minority groups. Moreover, transportation can be more than a means of access, it can also be a form of recreation itself, providing opportunities for visitors to experience and appreciate parks and related areas. But, differences in desirability of transportation recreation opportunities across recreation settings and among racial/ethnic groups are rarely addressed. The intent of this dissertation is three-fold: 1) identify transportation related barriers impacting visitation to national parks by racial/ethnic groups, and the effects of transportation on the visiting national parks, 2) identify the differences in indicators of the transportation recreation opportunity spectrum among racial/ethnic visitors and across recreation settings, 3) measure spatial accessibility of national parks and the effects of spatial accessibility and other factors on visitation to national parks among racial/ethnic groups. The first phase of research is designed to identify barriers to visiting national parks that are related to marginality, subculture, and discrimination hypotheses, and examine the effects of transportation incentives on visitation among racial/ethnic groups. Study results found that racial/ethnic minority groups visited national parks less frequently than Whites. Hispanics were more likely to perceive transportation-related barriers to visiting national parks than Whites. Moreover, providing transportation incentives can increase visitation by Hispanics significantly. The second phase of research developed indicators for a transportation recreation opportunity spectrum (T-ROS), and examined the differences in desirability for T-ROS indicators among alternative transportation modes, different types of recreation settings, and different racial/ethnic groups. Study results identified the important indicators for transportation service in different types of recreation areas, which can help inform transportation planning and management for the NPS. The final phase of research examined the spatial accessibility of national parks from different geographic locations by incorporating geospatial analytics, assessed the spatial accessibility of different types of national parks among racial/ethnic groups, and estimated the effects of spatial accessibility on visitation to national parks. Results showed that Hispanics and Blacks had higher accessibility to national parks than Whites within short distance radii, however, Blacks and Hispanics were more likely to perceive distance as a barrier to visiting national parks than Whites. Study results can help the NPS understand the spatial structure of national parks, provide visual information for visitors about proximate national parks and recreation opportunities, and identified effective management strategies for enhancing visitation of racial/ethnic minority groups from different geographic areas.

Rivers deliver significant macronutrients and sediments to lakes that can vary substantially throughout the year. These nutrient and sediment loadings, exacerbated by winter and spring runoff, impact aquatic ecosystem productivity and drive the formation of harmful algae blooms. The source, extent and magnitude of nutrient and sediment loading can vary drastically due to extreme weather events and hydrologic processes, such as snowmelt or high flow storm events, that dominate during a particular time period, making the temporal component (i.e., time over which the loading is estimated) critical for accurate forecasts. In this work, we developed a data-driven framework that leverages the temporal variability embedded in these complex hydrologic regimes to improve loading estimates. Identifying the "correct" time scale is an important first step for providing accurate estimates of seasonal nutrient and sediment loadings. We use water quality concentration and associated 15-minute discharge data from nine watersheds in Vermont's Lake Champlain Basin to test our proposed framework. Optimal time periods were selected using a hierarchical cluster analysis that uses the slope and intercept coefficients from individual load-discharge regressions to derive improved linear models. These optimized linear models were used to improve estimates of annual and "spring" loadings for total phosphorus, dissolved phosphorus, total nitrogen, and total suspended loads for each of the nine study watersheds. The optimized annual regression model performed ~20% better on average than traditional annual regression models in terms of Nash-Sutcliffe efficiency, and resulted in ~50% higher cumulative load estimates with the largest difference occurring in the "spring". In addition, the largest nutrient and sediment loadings occurred during the "spring" unit of time and were typically more than 40% of the total annual estimated load in a given year. The framework developed here is robust and may be used to analyze other units of time associated with hydrologic regimes of interest provided adequate water quality data exist. This, in turn, may be used to create more targeted and cost-effective management strategies for improved aquatic health in rivers and lakes.

Silviculture practices interact with multiple sources of variability to influence regeneration trends in northern hardwood forests. There is uncertainty whether low-intensity selection harvesting techniques will result in desirable tree regeneration. Our research is part of a long-term study that tests the hypothesis that a silvicultural approach called "structural complexity enhancement" (SCE) can promote accelerated development of late-successional forest structure and functions. Our objective is to understand the regeneration dynamics following three uneven-aged forestry treatments modified to increase postharvest structural retention: single-tree selection, group selection, and SCE. In terms of regeneration densities and composition, how do light availability, competition, seedbad, and herbivory interact with overstory treatment effects? To explore these relationships, manipulations and controls were replicated across 2-hectare treatment units at two sites in Vermont, USA. Forest inventory data were collected pre-harvest and 13 years post-harvest. We used linear mixed effects models with repeated measures to evaluate the effects of treatment on seedling and sapling abundances and diversity (Shannon-Weiner H'). Multivariate analyses evaluated the relative predictive strength of treatment versus alternative sources of ecological variability. Thirteen-years post-harvest, the harvested treatments were all successful in recruiting a sapling class with a significantly higher mean than the control. However, in all of the treatments prolific beech regeneration dominated the understory in patches. Seedling densities exhibited pulses of recruitment and mortality with a significant positive treatment effect on all harvested treatments in the first four years post-harvest. Seedling diversity was maintained, while sapling diversity was negatively influenced by herbivory (deer and moose browse) and leaf litter substrate. Multivariate analyses suggest that while treatment had a dominant effect, other factors were strongly influential in driving regeneration responses. Results indicate variants of uneven-aged systems that retain or enhance stand structural complexity, including old-growth characteristics, generally regenerate at adequate and desirable densities depending on site conditions.

Shoreline hardening and construction of restoration oyster reefs are occurring at rapid rates throughout Chesapeake Bay and little research has been conducted to determine whether installment of a hardened shoreline and oyster reef placement has an effect on the surrounding benthic infaunal communities. I investigated the effects of shoreline development and oyster reefs on benthic communities in Lynnhaven, Virginia. Throughout Lynnhaven, I determined the effects of shoreline type (natural marsh, oyster reef, rip-rap and bulkhead), sediment grain size, Total Organic Carbon/Total Nitrogen (TOC/TN) of the sediment, and predation (caging study) on density, biomass, and diversity of benthic infauna. An information-theoretic approach using Akaike’s Information Criterion (AIC) was used. Of the variables measured, shoreline type was the best predictor of benthic infaunal density (highest density at oyster reefs and lowest at bulkheads), while sediment composition (grain size and TOC/TN) and predators were the best predictors of biomass and diversity. Lynnhaven is a polyhaline, shallow, semienclosed, natural marsh-dominated system with high overall productivity, which could be masking any small-scale disturbances due to shoreline hardening at the sites. A Before-After-Control-Impact (BACI) study was completed at two sites (Eastern Branch and Linkhorn Bay) in Lynnhaven to examine the benthos before and after placement of oyster reefs. Replicate samples for benthic infauna, sediment grain size, and sediment TOC/TN were taken before and one year after reef placement. Based on the AIC analysis, oyster reefs had a positive effect on infaunal density at the Linkhorn Bay site after one year, mainly attributed to an influx of the bivalve Gemma gemma. The density increase occurred even with a decrease in polychaete density. There was no change in infaunal biomass or diversity at this site. At the Eastern Branch site, there was no effect of oyster reefs on density, biomass, or diversity. To characterize the benthos prior to reef placement, benthic samples were collected at two sites (Eastern Branch and Linkhorn Bay) in Lynnhaven. Four reef types (oyster shell, rip-rap, concrete modules, and reef ball) were deployed at both sites. Oyster production values for existing oyster reefs were used to estimate expected oyster production on each reef type. Biomass estimates and published P:B ratios for each taxa were used to calculate secondary production for benthic infauna and oysters. Lost benthic production due to each reef type at both sites was compared to estimated oyster production on each reef type to determine if each reef compensated for benthic production lost by placing the reefs on top of the benthos. Oyster production on oyster shell and reef ball reefs compensated for benthic production lost due to placement of the reefs at both sites. Oyster productivity on rip-rap and concrete module reefs did not compensate for lost benthic production at the highly productive Eastern Branch site, and barely compensated for lost benthos at the lower productivity Linkhorn Bay site. The preservation of natural marsh and use of the proper types of oyster reefs could help maintain the high productivity of both the benthic community and the Lynnhaven system itself.

The International Organization of Standardization (ISO) has created a series of voluntary standards (ISO 14000) which promote waste reduction and improve businesses’ environmental management. ISO 14001 is the Environmental Management System portion of ISO 14000 requiring employee awareness and involvement. The Robert Bosch Corporation is undergoing ISO 14001 certification. In this study, a 23-question survey was used to evaluate Bosch employees’ awareness of ISO 14000 and their support of a waste reduction program at four plants (Johnson City, TN; Sumter, South Carolina; Ashland, Ohio; and South Bend, Indiana). Employees surveyed were not yet familiar with ISO 14000 and that their awareness varied across job title and location. Employees were pro-environment and supported waste reduction programs under the condition they would not be penalized financially as a result. Results of this study will be used to identify strengths and weaknesses in EMS training at the surveyed facilities.

Bison spp. (bison) fossils are scarce on the Colorado Plateau, especially within the greater Grand Canyon region. Because of the poor fossil record for bison on the plateau and in Grand Canyon National Park, various resource managers have surreptitiously designated bison a nonnative and human-introduced species. The lack of evidence for bison seems to be the result of collection bias rather than a true lack of bison remains. Today, Grand Canyon National Park has a neighboring herd of 350 bison that have meandered unwantedly onto National Park lands from neighboring Forest Service and State of Arizona lands. This study spatiotemporally illustrates bison are recently native to the greater Grand Canyon area based on previously misidentified specimens in archaeological collections. Data here may require resource managers to reconsider whether or not bison should be reconsidered a native species to the Grand Canyon National Park and elsewhere on the Colorado Plateau.