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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

An approach for systematically developing environmental assessment information for small-to medium enterprises

Robb, Christopher 12 1900 (has links)
No description available.
42

Negotiating knowledges, shifting access| Natural resource governance with Indigenous communities and state agencies in the Pacific Northwest

Diver, Sibyl Wentz 31 March 2015 (has links)
<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>
43

Response of Pinyon-juniper woodlands to fire, chaining, and hand thinning

Gentilcore, Dominic M. 17 July 2015 (has links)
<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, R<sup>2</sup>=.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>
44

Forest communities along soil, acid deposition, and climate gradients of the Appalachian Trail

Quant, Juliana 10 September 2014 (has links)
<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>
45

Stage III N-saturated forested watershed rapidly responds to declining atmospheric N deposition

Sabo, Robert D. 10 September 2014 (has links)
<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 NO<sub>3</sub>-N pools, unprocessed atmospheric NO<sub>3</sub>-N in base flow, and significant reductions in NO<sub>3</sub>-N yield in response to decreased atmospheric N deposition. A lumped conceptual model, incorporating a dormant season NO<sub>3</sub>-N flush, was proposed that explains forest response to decreased deposition and sheds light on the hydrologic processes that govern the storage/release of NO<sub>3</sub>-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>
46

An outcome-based assessment of the New York State Department of Environmental Conservation freshwater wetlands regulatory system in Central New York

Bliss, Kevin R. 06 September 2014 (has links)
<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>
47

Vulnerability of groundwater to perchloroethylene contamination from dry cleaners in the Niles Cone Groundwater Basin, southern Alameda County, California

Jurek, Anne C. 11 November 2014 (has links)
<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>
48

The costs of corporate social responsibility and the role of civil society pressure

Kayser, Susan A. 18 November 2014 (has links)
<p> Having a reputation for being socially responsible is increasingly important to firm managers. To bolster their reputation, many firms have begun adopting corporate social responsibility (CSR) initiatives. The existing literature has primarily addressed the benefits of engaging in CSR initiatives, but has largely ignored the costs. This dissertation empirically explores the various costs of engaging in CSR and the critical role that civil society plays in creating those costs. </p><p> The first study, co-authored with Michael Toffel and John Maxwell, focuses on the non-market costs associated with adopting a CSR initiative. To manage reputational risks associated with supply chains, buyers are increasingly seeking information about their suppliers' labor and environmental performance. We hypothesize particular circumstances in which buyers can screen suppliers that have representative disclosures based on their participation in the Global Compact, which requires a public commitment and a public report. We find that the threat of scrutiny from civil society can deter firms with misrepresentative disclosures from participating. </p><p> In the second study, I examine the market response to the apparel industry after the collapse of Rana Plaza. CSR initiatives have been found to help firms preserve firm-value after a negative social or environmental event occurs. However, CSR initiatives may also signal to investors that the firm will respond by self-regulating to help repair the industry's aggregate reputation. I find that firms with CSR initiatives are harmed more so than those without initiatives after the collapse and that this is driven by pressure from civil society, but mitigated when firms can "cash in" on their investments. </p><p> In the third study, I analyze whether a company's symbolic policy to protecting the environment will lead to the adoption of a substantive CSR initiative, specifically an environmental management system (EMS). I find that firms with symbolic policies will be especially likely to adopt an EMS when the firm is subject to strong pressures from civil society. I also find that firms with symbolic policies are less likely to adopt an EMS when they face stronger peer pressure, suggesting that firms may use their symbolic policy as a substitute for a more substantive program.</p>
49

Quantifying the restorable water volume of Sierran meadows

Emmons, Jason Daniel 31 May 2014 (has links)
<p> The Sierra Nevada is estimated to provide over 66% of California's water supply, which is largely derived from snowmelt. Global climate warming is expected to result in a decrease in snow pack and an increase in melting rate, making the attenuation of snowmelt by any means, an important ecosystem service for ensuring water availability. Montane meadows are dispersed throughout the mountain range providing wildlife habitat, water filtration, and water storage. Despite the important role of meadows in the Sierra Nevada, the majority are degraded from stream incision, which increases volume outflows and reduces overbank flooding, thus reducing infiltration and potential water storage. Restoration of meadow stream channels would therefore improve hydrological functioning, including increased water storage. The potential water holding capacity of restored meadows has yet to be quantified, thus this research seeks to address this knowledge gap by estimating the restorable water volume due to stream incision. More than 17,000 meadows were analyzed by categorizing their erosion potential using channel slope and soil texture, ultimately resulting in six general erodibility types. Field measurements of over 100 meadows, stratified by latitude, elevation, and geologic substrate, were then taken and analyzed for each erodibility type to determine average depth of incision. Restorable water volume was then quantified as a function of water holding capacity of the soil, meadow area and incised depth. Total restorable water volume across meadows in the Sierra Nevada was found to be 120 x 10<sup>6</sup>m<sup>3</sup>, or approximately 97,000 acre-feet. Using 95% confidence intervals for incised depth, the upper and lower bounds of the total restorable water volume were found to be 107 x 10<sup>6</sup>m<sup> 3</sup> &ndash; 140 x 10<sup>6</sup>m<sup>3</sup>. Though this estimate of restorable water volume is small in regards to the storage capacity of typical California reservoirs, restoration of Sierra Nevada meadows remains an important objective. Storage of water in meadows benefits California wildlife, potentially attenuates floods, and elevates base flows, which can ease effects to the spring snowmelt recession from the expected decline in Sierran snowpack with atmospheric warming.</p>
50

Hydrologic dynamics control dissolved organic matter export from watersheds| Fields-scale processes in a small, artificially drained agricultural catchment, and patterns across ecosystems

Bellmore, Rebecca Anne 07 March 2015 (has links)
<p>Dissolved organic matter (DOM) is an important component of nutrient cycling and energy transfer within and between ecosystems. Understanding controls over the magnitude and quality of DOM that is transferred from soils to surface water is needed to better characterize the terrestrial-aquatic carbon flux and effects of terrestrial DOM on downstream ecosystems. A meta-analysis of the response of in-stream dissolved organic nitrogen concentration (DON) to high flow events indicates that DON typically increases with flow across a wide range of ecosystem types, likely as novel DOM sources in the landscape are mobilized and transported to streams and rivers. Mechanisms controlling DOM export, including dissolved organic carbon (DOC) and DON concentrations and the quality of DOM, were examined in a small agricultural catchment in eastern Washington State. In the soil column, DOC concentration declined and source of DOM shifted from humic-like and plant-derived to microbially-derived with depth through the profile. Across seasons and years, DOM exported via drain discharge during low flows resembled that found deep in the soil profile, and DOM exported during high flows suggests topsoil and litter sources contribute to export. A simple mixing model suggests that litter leachate can contribute over 50% of DOM during peak flow. Based on modeled contributions of litter, topsoil and subsoil DOM during storm events, DOC concentration is over-predicted, except for peak flows, suggesting removal via sorption and/or microbial decomposition in the soil column control DOC export on the timescale of events. Although the character of exported DOM shifts with flow conditions, laboratory incubations suggest bioavailability to the stream sediment microbial community is consistently low, with a maximum of 7% loss over 6 days, indicating exported DOM is likely transported beyond the immediate stream reach. An analysis of anticipated effects of climate change on the flow regime in the catchment projects the wettest years to become more variable, with non-linear effects on the magnitude of DOC export. Finally I explore how climate change assessments can be incorporated into nonpoint source nutrient management plans, despite current uncertainty about the magnitude and timeframe of climate effects on nutrient loading.

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