<p> The objectives of this study were to measure injuries and impairments directly observed from gags <i>Mycteroperca microlepis</i> caught and released within a large-scale recreational fishery, develop methods that may be used to rapidly assess the condition of reef fish discards, and estimate the total portion of discards in the fishery that suffer latent mortality. Fishery observers were placed on for-hire charter and headboat vessels operating in the Gulf of Mexico from June 2009 through December 2012 to directly observe reef fishes as they were caught by recreational anglers fishing with hook-and-line gear. Fish that were not retained by anglers were inspected and marked with conventional tags prior to release. Fish were released in multiple regions over a large geographic area throughout the year and over multiple years. The majority of recaptured fish were reported by recreational and commercial fishers, and fishing effort fluctuated both spatially and temporally over the course of this study in response to changes in recreational harvest restrictions and the Deepwater Horizon oil spill. Therefore, it could not be assumed that encounter probabilities were equal for all individual tagged fish in the population. Fish size and capture depth when fish were initially caught-and-released also varied among individuals in the study and potentially influenced recapture reporting probabilities. The Cox proportional hazards regression model was used to control for potential covariates on both the occurrence and timing of recapture reporting events so that relative survival among fish released in various conditions could be compared. A total of 3,954 gags were observed in this study, and the majority (77.26%) were released in good condition (condition category 1), defined as fish that immediately submerged without assistance from venting and had not suffered internal injuries from embedded hooks or visible damage to the gills. However, compared to gags caught in shallower depths, a greater proportion of gags caught and released from depths deeper than 30 meters were in fair or poor condition. Relative survival was significantly reduced (alpha <u>&lt;</u>0.05) for gags released in fair and poor condition after controlling for variable mark-recapture reporting rates for different sized discards among regions and across months and years when individual fish were initially captured, tagged and released. Gags released within the recreational fishery in fair and poor condition were 66.4% (95% C.I. 46.9 to 94.0%) and 50.6% (26.2 to 97.8%) as likely to be recaptured, respectively, as gags released in good condition. Overall discard mortality was calculated for gags released in all condition categories at ten meter depth intervals. There was a significant linear increase in estimated mortality from less than 15% (range of uncertainty, 0.1-25.2%) in shallow depths up to 30 meters, to 35.6% (5.6-55.7%) at depths greater than 70 meters (p &lt; 0.001, R² = 0.917). This analysis demonstrated the utility of the proportional hazards regression model for controlling for potential covariates on both the occurrence and timing of recapture events in a large-scale mark-recapture study and for detecting significant differences in the relative survival of fish released in various conditions measured under highly variable conditions within a large-scale fishery.</p>

<p> This thesis estimates the impacts of rooftop photovoltaic (PV) capacity on electricity generation and CO2 emissions in America's Pacific Northwest. The region's demand for electricity is increasing at the same time that it is attempting to reduce its greenhouse gas emissions. The electricity generated by rooftop PV capacity is expected to displace electricity from fossil fueled electricity generators and reduce CO2 emissions, but when and how much? And how can this region maximize and focus the impacts of additional rooftop PV capacity on CO2 emissions? To answer these questions, an hourly urban rooftop PV generation profile for 2009 was created from estimates of regional rooftop PV capacity and solar resource data. That profile was compared with the region's hourly fossil fuel generation profile for 2009 to determine how much urban rooftop PV generation reduced annual fossil fuel electricity generation and CO2 emissions. Those reductions were then projected for a range of additional multiples of rooftop PV capacity. The conclusions indicate that additional rooftop PV capacity in the region primarily displaces electricity from natural gas generators, and shows that the timing of rooftop PV generation corresponds with the use of fossil fuel generators. Each additional Wp/ capita of rooftop PV capacity reduces CO2 emissions by 9,600 to 7,300 tons/ year. The final discussion proposes some methods to maximize and focus rooftop PV impacts on CO2 emissions, and also suggests some questions for further research.</p>

No description available.

<p> Semi-arid forests are in a period of rapid transition as a result of unprecedented landscape scale fires, insect outbreaks, drought, and anthropogenic land use practices. Understanding how historically episodic disturbances led to coherent forest structural and spatial patterns that promoted resilience and resistance is a critical part of addressing change. Here my coauthors and I apply metabolic scaling theory (MST) to examine scaling behavior and structural patterns of semi-arid conifer forests in Arizona and New Mexico. We conceptualize a linkage to mechanistic drivers of forest assembly that incorporates the effects of low-intensity disturbance, and physiologic and resource limitations as an extension of MST. We use both aerial LiDAR data and field observations to quantify changes in forest structure from the sub-meter to landscape scales. We found: (1) semi-arid forest structure exhibits MST-predicted behaviors regardless of disturbance and that MST can help to quantitatively measure the level of disturbance intensity in a forest, (2) the application of a power law to a forest overstory frequency distribution can help predict understory presence/absence, (3) local indicators of spatial association can help to define first order effects (e.g. topographic changes) and map where recent disturbances (e.g. logging and fire) have altered forest structure. Lastly, we produced a comprehensive set of above-ground biomass and carbon models for five distinct forest types and ten common species of the southwestern US that are meant for use in aerial LiDAR forest inventory projects. This dissertation presents both a conceptual framework and applications for investigating local scales (stands of trees) up to entire ecosystems for diagnosis of current carbon balances, levels of departure from historical norms, and ecological stability. These tools and models will become more important as we prepare our ecosystems for a future characterized by increased climatic variability with an associated increase in frequency and severity of ecological disturbances. </p>

<p> Despite an increasing interest among land managers in collaborative management and learning from place-based Indigenous knowledge systems, natural resource management negotiations between Indigenous communities and government agencies are still characterized by distrust, conflict, and a history of excluding Indigenous peoples from decision-making. In addition, many scholars are skeptical of Indigenous communities attempting to achieve self-determination through bureaucratic and scientific systems, which can be seen as potential mechanisms for co-opting Indigenous community values (e.g. Nadasdy 2003). </p><p> This dissertation considers how Indigenous communities and state agencies are meeting contemporary natural resource governance challenges within the Pacific Northwest. Taking a community-engaged scholarship approach, the work addresses two exemplar case studies of Indigenous resource management negotiations involving forest management with the Karuk Tribe in California (U.S.) and the X&aacute;xli'p Indigenous community in British Columbia (Canada). These cases explore the ways and degree to which Indigenous peoples are advancing their self-determination interests, as well as environmental and cultural restoration goals, through resource management negotiations with state agencies&mdash;despite the ongoing barriers of uneven power relations and territorial disputes. </p><p> Through the 1990s and 2000s, both the X&aacute;xli'p and Karuk communities engaged with specific government policies to shift status quo natural resource management practices affecting them. Their respective strategies included leveraging community-driven management plans to pursue eco-cultural restoration on their traditional territories, which both overlap with federal forestlands. In the X&aacute;xli'p case, community members successfully negotiated the creation of the X&aacute;xli'p Community Forest, which has provided the X&aacute;xli'p community with the exclusive right to forest management within the majority of its traditional territory. This <i>de jure</i> change in forest tenure facilitated a significant transfer of land management authority to the community, and long-term forest restoration outcomes. In the Karuk case, tribal land managers leveraged the Ti Bar Demonstration Project, a <i>de facto</i> co-management initiative between the Forest Service and the Karuk Tribe, to conduct several Karuk eco-cultural restoration projects within federal forestlands. Because the Ti Bar Demonstration Project was ultimately abandoned, the main project outcome was building the legitimacy of Karuk land management institutions and creating a wide range of alliances that support Karuk land management approaches. </p><p> Through my case studies, I examined how Indigenous resource management negotiations affect knowledge sharing, distribution of decision-making authority, and longstanding political struggles over land and resource access. I first asked, how is Indigenous knowledge shaping natural resource management policy and practice? My analysis shows that both communities are strategically linking disparate sets of ideas, including Traditional Ecological Knowledge (TEK) and Western scientific knowledge, in order to shape specific natural resource governance outcomes. My second question was, how does access to land and resources shift through Indigenous resource management agreements? This work demonstrates that both communities are shifting access to land and resources by identifying "pivot points": existing government policies that provide a starting point for Indigenous communities to negotiate self-determination through both resisting and engaging with government standards. And third, I considered how do co-management approaches affect Indigenous sovereignty and self-determination? The different case outcomes indicate that the ability to uphold Indigenous resource management agreements is contingent upon establishing long-term institutional commitments by government agencies, and the broader political context. </p><p> This work emphasizes the importance of viewing the world from the standpoint of individuals who are typically excluded from decision-making (Harding 1995, 1998). Pursuing natural resource management with Indigenous peoples is one way for state agencies to gain innovative perspectives that often extend beyond standard resource management approaches, and consider longstanding relationships between people and the environment in a place-based context. Yet the assumption that tribal managers would export Indigenous knowledge to agency "professionals" or other external groups, supposedly acting on behalf of Indigenous peoples, reflects a problematic lack of awareness about Indigenous perspectives on sovereignty and self-determination--central goals for Indigenous communities that choose to engage in natural resource management negotiations. </p><p> Several implications emerge from these findings. First, Indigenous community representatives need to be involved in every step of natural resource management processes affecting Indigenous territories and federal forestlands, especially given the complex, multi-jurisdictional arrangements that govern these areas. Second, there is a strong need to generate funding that enables Indigenous communities to self-determine their own goals and negotiate over land management issues on a more level playing field. Finally, more funding must be invested in government programs that support Indigenous resource management.</p>

<p> Pinyon-juniper (<i>Pinus monophylla &ndash; Juniperus osteosperma</i>) woodlands have expanded and infilled over the last 150 years to cover more than 40 million ha in the Great Basin. Many land managers seek to remove Pinyon-juniper trees using a variety of treatments. This thesis looks at six different Pinyon-juniper removal projects in Central and Eastern Nevada. We established a total of 73 vegetation and soil monitoring plots (38 treated, 35 adjacent untreated) across six Pinyon-juniper removal projects in Central and Eastern Nevada to look at the effects of fire, hand thinning, and chaining. The four burns examined together in Chapter 1 had similar elevation, precipitation, and pre-treatment vegetation communities in the untreated areas, but the treated areas had significantly different responses to treatment. With nonmetric multidimensional scaling (NMS), we found a useful 3-axis ordination of the plots (stress=7.1, R²=.966). Within ordination space, the treated plots were well grouped by parent material. These results informed a Poisson generalized linear model that found parent material factorized explained 86.5% of the deviance in cheatgrass (<i>Bromus tectorum</i>) cover at the treated plots. The projects on soils derived from welded tuff had very little cheatgrass while soils derived from limestone or mixed limestone/volcanics were dominated by cheatgrass. Parent material should be considered an important factor when planning Pinyon-juniper removal treatments. Chapter 2 examined the effects of a hand thinning. The hand thinning significantly reduced tree cover [F(1,10) = 7.43, p = 0.027] to less than 2%. Perennial grasses on the site are slightly higher in the treated area. There was a significant increase in perennial grass cover from 2013 to 2014 [F(1,10) = 14.5, p = 0.003]. The hand thinning did not have significant effects on shrubs, annual grasses, annual forbs, perennial forbs, ground cover, stability, species richness, diversity, infiltration, or gap structure. Because hand thinning does not remove the shrubs or other perennials, site resistance can be maintained. With sufficient understory vegetation to maintain resistance post treatment (as in phase I or early phase II Pinyon-juniper woodlands), nonnative annual grasses are less likely to dominate after treatment. Chapter 3 examined the effects of a chaining. The effects of the 40-year old chaining are still significant even though Pinyon-juniper trees are reinvading and make up >5% of the cover in the treated area. The treated areas still have a much more productive understory than adjacent untreated areas. Perennial grass cover, frequency, and density was 2-5 times greater in the chained area. The treated area had fewer large gaps (>100 cm). However, interspace infiltration times were slower in the treatment (t(4)=-2.14, p=0.09). Surface and subsurface soil aggregate stability remained significantly lower in the treatment for vegetation-protected and unprotected samples (t(4)=3.53, p=0.024; t(4)=3.10, p=0.036). Chainings have long-term benefits for vegetation, but also long term impacts on soils and hydrologic ecosystem processes. When planning Pinyon-juniper removal treatments, land managers should consider the plant community, temperature and precipitation regime, and soils at the potential treatment location to better achieve desired outcomes.</p>

<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 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>