<p> The exotic annual <i>Bromus tectorum</i> (cheatgrass) commonly occurs in dense, near-monocultures in the Great Basin, U.S.A. after diverse native plant communities have been mostly extirpated. Efforts to reestablish native species via direct seeding, typically with commercially produced, non-local seeds, are often unsuccessful. In addition to abiotic factors that often limit establishment, <i>B. tectorum</i> competition can impede native establishment in highly invaded communities, and commercially produced seeds may differ from local genotypes in their responses to these limitations. The phenomenon of complete <i>B. tectorum</i> stand failure, or 'die-off', can leave areas within near-monocultures devoid of growth for one or more years. Such areas may represent restoration opportunities if native seeds can establish within them. In October 2012, local and nonlocal (commercial) sources of <i>Poa secunda</i> (Sandberg bluegrass) and <i> Elymus elymoides</i> (bottlebrush squirreltail) were precision-planted in a recent die-off and adjacent near-monoculture (control) in northern Nevada under six treatments: litter removal, fungicide application, and no treatment; each with and without added simulated precipitation. I addressed the following questions: 1) Can native species be successfully restored in recent <i> B. tectorum</i> die-offs, and is establishment related to seedbed treatments and competition with <i>B. tectorum</i>? 2) Do local and nonlocal materials differ in their performance as restoration material, and if so, are these differences consistent across seedbed treatments and in and out of a recent die-off? Seeded plots were monitored nine times throughout two growing seasons for emergence and seedling activity, and seedling growth was measured in May of the first season. Emergence of native seeds was significantly lower in die-off plots, but there were significantly more actively growing seedlings of both species in die-off plots than in adjacent control plots by the end of the first growing season, and seedlings in the die-off exhibited more leaves, increase late season vigor, and, for <i>E. elymoides</i>, increased height. Second year survival patterns also suggested greater establishment in die-off plots. Local <i>P. secunda</i> demonstrated improved performance over nonlocal material ('Mt. Home' germplasm) in both seasons, whereas nonlocal <i>E. elymoides</i> (`Toe Jam Creek' germplasm) demonstrated aspects of higher performance than the local collection in the first year but not the second. Litter removal had a positive influence on seedling activity for both species, but only affected the survival of <i> P. secunda</i>. Late autumn (early growing season) water addition affected emergence timing for both species and resulted in more <i>E. elymoides </i> seedlings, but this affect was equal across controls and die-offs. Although these results are representative of conditions at only one site, they suggest that <i>B. tectorum</i> die-off may support increased establishment of native species regardless of seedbed treatment, and may therefore represent valuable opportunities for restoration. Also, they indicate that local and nonlocal seeds differ in performance in important but idiosyncratic ways, which supports the belief that seed source should be considered as a factor affecting restoration success but contradicts the idea of generalizable local vs. nonlocal performance patterns.</p>

<p> The global issues of acid deposition and climate change call for a greater understanding of the relative influence of broad gradients of acid deposition, climate, soil, and stand characteristics in montane temperate forests. At each of 30 sites along the Appalachian Trail, I measured overstory composition and density (including snags) using the point-centered quarter method (9 plots) and characterized understory species composition and cover (27 plots, 1 m2 each). Analytical approaches included NMS ordination, multiple linear regression, and beta regression. Spruce-fir sites had lower understory richness, lower understory cover, higher cover of strongly acidophytic understory species, and greater regeneration of canopy trees. Temperature affected understory composition and precipitation increased understory cover. The proportion of snags among canopy trees was highest on cool sites with dense canopies. The impact of nitrogenous deposition was limited, but it may have a fertilizer effect. Sites with acidified (high Al) soil had poor canopy regeneration. </p>

<p> This study used a mass balance approach by characterizing the input, output, and sink rates of N in order to assess a declared "stage III N-saturated forest" response to decreased atmospheric N deposition in western Maryland. Relying on the conceptual model of kinetic N-saturation to holistically link stream, vegetative, soil, and atmospheric compartments and the use of a novel stable isotopic technique, the study demonstrated dynamic soil NO₃-N pools, unprocessed atmospheric NO₃-N in base flow, and significant reductions in NO₃-N yield in response to decreased atmospheric N deposition. A lumped conceptual model, incorporating a dormant season NO₃-N flush, was proposed that explains forest response to decreased deposition and sheds light on the hydrologic processes that govern the storage/release of NO₃-N among years. It is proposed that this flushing mechanism prevents forests from attaining higher stages of N-saturation and predicts forests will be responsive to further reductions in N deposition. </p>

<p> This dissertation evaluates freshwater wetland impact avoidance and mitigation resulting from the New York State Department of Environmental Conservation (NYSDEC) permitting program within Central New York. Concurrent with this, is an effort to ascertain wetland functionality through a rapid assessment approach to wetland evaluation. Three primary techniques were employed: First, NYSDEC permit decisions were compared to the NYSDEC Freshwater Wetland Regulation Guidelines on Compensatory Mitigation (NYSDEC 1993), to determine whether or not the Guidance was adhered to. Second, NYSDEC permit requirements were compared to the actual mitigation efforts conducted by a permittee in the field to determine whether or not the permittee complied with imposed requirements. And third, a rapid assessment approach comparing functions and values at wetland mitigation sites to the corresponding natural wetland that was impacted by NYSDEC permit issuance was used to determine whether or not the functions and values provided by the mitigation adequately replaced those lost at the original impacted wetland site. The results of this review indicate that the majority of wetland mitigation guidelines are not followed the majority of time. For example, less than one third of the time was mitigation based on plans providing short or long term goals or measurable performance criteria. Often permittees do not comply with imposed freshwater wetland permit requirements related to mitigation. More specifically, thirty five percent of the time, permit requirements for mitigation were not met for those files sampled. As for the functions and values being replaced, that is not happening with six out of nine measured functions: open space and aesthetic resources; erosion control; pollution treatment; protection of subsurface water resources; wildlife habitat; and flood control. The three functions found to be replaced by mitigation include recreation; sources of nutrients in freshwater food cycles and nursery grounds / sanctuaries for freshwater fish; and education and scientific research.</p>

<p> Levee Lake is a forested wetland system located within a Mississippi River oxbow meander scar in the American Bottom of the Northern Section of the Lower Mississippi River Bottomlands Division (White 1978) that has not been developed or converted to agricultural land. Because of its relatively undisturbed status, Levee Lake is representative of a presettlement wetland. In 1976, Levee Lake was documented with a 93-acre Grade B shrub swamp/marsh/pond (SSMP) community, qualifying for the Illinois Natural Areas Inventory (INAI). Additionally, 129 acres of Grade C wet floodplain forest surrounding the SSMP community was recorded (Nyboer and Reeves 1976). </p><p> Nyboer and Reeves (1976) described Levee Lake as the largest complex of marsh, pond, and swamp communities representing presettlement American Bottom conditions. They also identified potential draining efforts at site perimeters. Based on regulatory agency and Illinois Natural History Survey (INHS) documents as well as historical aerial photographs, perimeter portions of the forested wetland system and adjoining properties were subjected to decades of clearing and draining efforts prior to and following the 1976 survey. </p><p> This study involved evaluating the current floristic composition, natural communities, and the overall quality of the Levee Lake wetland system. The information from the current evaluation was then compared to the 1976 survey to examine how recorded disturbances have affected the condition, communities, and quality of the Levee Lake wetland system. The hypothesis of this study was that documented clearing, draining, and subsequent hydrologic alterations would likely cause changes in plant composition and natural communities since the 1976 INAI survey. </p><p> To accomplish this task, the transect (Transect 1 or T1) that was used for vegetative sampling in 1976 was re-created and used as a benchmark for 2012 vegetative sampling. To compare the plant composition from 1976 to 2012, twenty 0.25 meter (m)2 sampling plots were established along Transect 1. At each plot (T1P1 through T1P20), the relative cover of each vascular plant species was recorded and the resulting species data evaluated. To provide additional plant data for the site, herbaceous, shrub, and tree sampling was conducted via the <i>Critical Trends Assessment Program</i> (CTAP) protocols. Vegetative sampling was conducted in late summer/fall of 2012. </p><p> To evaluate the overall plant quality of Levee Lake and the existing natural communities, existing vegetation outside of the aforementioned transects was also recorded in late summer/fall of 2012. The overall site conditions and natural communities were observed and recorded during site visits in 2011, 2012, and 2014. The current natural communities were determined by the vegetative sampling, the overall site observations, as well as available aerial photographs and images. </p><p> Based on the research and field work, the native plant composition suffered a reduction in quality. Additionally, communities suffered a reduction in quality and a shift in community type. A reduction in water levels caused severe woody encroachment of the SSMP community identified in 1976. Today, only approximately 0.58-acre [0.23 hectare (ha)] of Grade C marsh/pond community remains. In 1976, the pond community was considered an exceptional feature with the surrounding shrub swamp/marsh community considered a significant feature. Although most of the former 93-acre Grade B SSMP community suffered from severe woody encroachment, recent wetland restorations to the north and to the south appear to have aided in returning hydrology to this community. Herbaceous, shrub, and tree vegetation data collected in the CTAP plots provided further evidence of wetland and swamp conditions. The former SSMP community has evolved into a Grade C swamp/marsh/pond (SMP) community. An approximate 11.73-acre (4.75 ha) Grade D marsh/wet meadow has evolved in the southwestern region that was subjected to decades of clearing and draining disturbance (White 1978; White and Madany 1978). Further evidence of a shift in plant composition and communities between species along Transect 1 in 1976 and in 2012 was shown through the NMDS ordination and an ANOSIM test which showed that plot communities distinctly differ between the two years (Minchin 2013). (Abstract shortened by UMI.) </p><p> </p>

<p> This study investigated two important aspects of hydrologic effects of low impact development (LID) practices at the watershed scale by (1) examining the potential benefits of scaling up of LID design, and (2) evaluating downstream effects of LID design and its spatial translation within a watershed. The Personal Computer Storm Water Management Model (PCSWMM) was used to model runoff reduction with the implementation of LID practices in Deer Creek watershed (DCW), Missouri. The model was calibrated from 2003 to 2007 (R² = 0.58 and NSE = 0.57), and validated from 2008 to 2012 (R² = 0.64 and NSE = 0.65) for daily direct runoff. Runoff simulated for the study period, 2003 to 2012 (NSE = 0.61; R² = 0.63), was used as the baseline for comparison to LID scenarios. Using 1958 areal imagery to assign land cover, a predevelopment scenario was constructed and simulated to assess LID scenarios' ability to restore predevelopment hydrologic conditions. The baseline and all LID scenarios were simulated using 2006 National Land Cover Dataset.</p><p> The watershed was divided in 117 subcatchments, which were clustered in six groups of approximately equal areas and two scaling concepts consisting of incremental scaling and spatial scaling were modelled. Incremental scaling was investigated using three LID practices (rain barrel, porous pavement, and rain garden). Each LID practice was simulated at four implementation levels (25%, 50%, 75%, and 100%) in all subcatchments for the study period (2003 to 2012). Results showed an increased runoff reduction, ranging from 3% to 31%, with increased implementation level. Spatial scaling was investigated by increasing the spatial extent of LID practices using the subcatchment groups and all three LID practices (combined) implemented at 50% level. Results indicated that as the spatial extent of LID practices increased the runoff reduction at the outlet also increased, ranging from 3% to 19%. Spatial variability of LID implementation was examined by normalizing LID treated area to impervious area for each subcatchment group. The normalized LID implementation levels for each group revealed a reduction in runoff at the outlet of the watershed, ranging from 0.6% to 3.7%. This study showed that over a long-term period LID practices could restore pre-development hydrologic conditions. The optimal location for LID practice implementation within the study area was found to be near the outlet; however, these results cannot be generalized for all watersheds. </p>

<p> Releases of perchloroethylene (PCE) from dry cleaners pose a threat to groundwater quality. An assessment was performed of the Niles Cone Groundwater Basin to determine its vulnerability to PCE contamination from both historic and more recently operating dry cleaners. Sensitivity assessments of the Basin's two subbasins were performed using a modification of the DRASTIC Index Method, whereby the hydrogeological variables of depth to water, aquifer media, vadose zone media, and soil drainage classification were represented by a range of sensitivity categories and ratings assigned to each range. A source assessment was performed by identifying the locations of historic and presently operating dry-cleaning plants and assigning a threat ranking to each based on the approximate years in which the four generations of dry-cleaning machinery were introduced. Using ArcGIS, the sensitivity assessments and the source assessment were mapped, and the source assessment was superimposed over the sensitivity maps to create vulnerability maps of the two subbasins. The most sensitive area of the Below Hayward Fault subbasin in the forebay area near the Hayward Fault is due to a higher proportion of coarse-grained aquifer and vadose zone media and a thinner to absent aquitard due to deposition from the Alameda Creek. The existence of dry cleaners of higher threat makes this an area that is vulnerable to PCE contamination.</p>

<p> The economic turmoil of the past decade has reinvigorated the debate over the use of public funds to support local Extension efforts. State Extension groups across the country have begun to demonstrate their worth in a variety of ways, including attempting to show both the behavioral and economic outcomes of Extension initiatives. However, showing the value of the 4-H Youth Development Program has proved challenging. The benefits of joining youth programs tend to be latent, not fully manifesting for years or even decades until participants mature into adults. Studies are starting to provide insights into the social, physical and mental rewards of joining youth development organizations such as 4-H, but these behavioral outcomes are disproportionally reported when compared to economic studies. From 2012-2013 families enrolled in Oklahoma's 4-H Youth Development Shooting Sports Project were surveyed about their recreational spending habits. Economic contributions for the state of Oklahoma, and impacts on local economies are estimated using primary data and an IMPLAN model. These economic analyses provide estimates of the economic worth of one youth project overseen by the Oklahoma Cooperative Extension Service. Subsequently, policy makers are provided justification of the project not only from a social, physical, and mental perspective, but are additionally provided economic indicators of the project's immediate worth.</p>

<p> The assessment of herbivore habitat quality is traditionally based on quantifying the forages available to the animal across their home range through ground-based techniques. While these methods are highly accurate, they can be time-consuming and highly expensive, especially for herbivores that occupy vast spatial landscapes. The Unimak Island caribou herd has been decreasing in the last decade at rates that have prompted discussion of management intervention. Frequent inclement weather in this region of Alaska has provided for little opportunity to study the caribou forage habitat on Unimak Island. The overall objectives of this study were two-fold 1) to assess the feasibility of using high-resolution color and near-infrared aerial imagery to map the forage distribution of caribou habitat on Unimak Island and 2) to assess the use of a new high-resolution multispectral satellite imagery platform, RapidEye, and use of the "red-edge" spectral band on vegetation classification accuracy. Maximum likelihood classification algorithms were used to create land cover maps in aerial and satellite imagery. Accuracy assessments and transformed divergence values were produced to assess vegetative spectral information and classification accuracy. By using RapidEye and aerial digital imagery in a hierarchical supervised classification technique, we were able to produce a high resolution land cover map of Unimak Island. We obtained overall accuracy rates of 71.4 percent which are comparable to other land cover maps using RapidEye imagery. The "red-edge" spectral band included in the RapidEye imagery provides additional spectral information that allows for a more accurate overall classification, raising overall accuracy 5.2 percent.</p>

<p> Two US Forest Service draft monitoring protocols are used to assess the effectiveness of design channels at road-stream crossings by comparing their physical channel dimensions to those in the natural channel. Level II physical monitoring is a time intensive, quantitative and statistically based procedure for assessing effectiveness at selected sites. Level I physical monitoring is a less detailed, rapid procedure limited to a few simple measurements and observations for assessing effectiveness at a large number of sites. Study objectives were to: 1) test and refine the field methods for collecting data by the levels I and II physical monitoring protocols; 2) find a meaningful way to combine the data collected by levels I and II into separate effectiveness evaluations by each protocol; and, 3) evaluate whether the level I protocol can be used as a proxy for the level II protocol. Where the two protocols systematically differ, field data help distinguish why. </p><p> Study results for all objectives (combined) include: improved field methodologies, recommendations for further development, and separate summary rubrics for the levels I and II monitoring protocols. The recommendations are of three categories; channel metrics/data collection, methods of scoring each metric, and sample sizes. Some of most significant of those recommendations are described within the following paragraphs. </p><p> Data collection methods might be improved to save time, increase the accuracy of protocol evaluations, and facilitate agreement between the levels I and II protocol evaluation results. The techniques by which the level I bankfull stage and coarse fraction of the gradation metrics are collected should incorporate level II methods. Instructions for collecting level II coarse fraction of the gradation data should specify measuring all particles within the channel, including particles much larger than the sampling frame. The level I method by which the representative reach is selected should incorporate a basic longitudinal profile survey in which only the most prominent grade controls separating slope segments are captured. Decreasing the allowable gradient difference between the level II design channel and representative reach might also improve accuracy. The method by which the levels I and II protocols compare channel units (or channel unit sequences) between the design and representative reach should be equivalent, as should the rules by which slope segments and channel units are defined. Finally, the channel metrics of low flow width and bed irregularity are inconsistent with the objectives of physical effectiveness monitoring, in that they are aspects of habitat, rather than strong controls on channel form. I suggest they be eliminated from the levels I and II protocols. </p><p> The level II summary rubric scores most metrics statistically by a Wilcoxon Rank-Sum test of medians. For most metrics, the Wilcoxon Rank-Sum test appears to be a reasonable way to compare representative reach and design zone data. For the metrics of bed and bank irregularity, however, a test of distributions (e.g., Kolmogorov-Smirnov) is recommended instead. The coarse fraction of the gradation metric would be more fairly assessed if the modes of the particle size (in phi units) were compared instead of the medians. Doing so would allow the design and representative reach gradients to be slightly different (as does the criteria for selecting a representative reach) without penalizing the metric score. </p><p> The levels I and II summary rubric tools created were used to evaluate twelve AOP road-stream crossing designs. The performance of the levels I and II summary rubrics were then assessed by the evaluation results at those twelve sites. Levels I and II generally seemed to provide effectiveness evaluations which agreed with site observations, data, and photographs. Further, the summary rubrics facilitated concurrent evaluation of the many channel dimensions which together affect the hydraulic conditions experienced by aquatic organisms. In addition, the simple utility of the levels I and II summary rubric tools should encourage effectiveness monitoring and help restoration practitioners learn from their mistakes, ultimately improving aquatic organism passage design methods and results. (Abstract shortened by UMI.)</p>