974 resultados para Landscape Context


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Over the last one hundred years, compartmentalization and water management activities have reduced water flow to the ridge and slough landscape of the Everglades. As a result, the once corrugated landscape has become topographically and vegetationally uniform. The focus of this study was to quantify variation in surface flow in the ridge and slough landscape and to relate flow conditions to particulate transport and deposition. Over the 2002–2003 and 2003–2004 wet seasons, surface velocities and particulate accumulation were measured in upper Shark River Slough in Everglades National Park. Landscape characteristics such as elevation, plant density and biomass also were examined to determine their impact on flow characteristics and material transport. The results of this study demonstrate that the release of water during the wet season not only increases water levels, but also increased flow speeds and particulate transport and availability. Further, flow speeds were positively and significantly correlated with water level thereby enhancing particulate transport in sloughs relative to ridges especially during peak flow periods. Our results also indicate that the distribution of biomass in the water column, including floating plants and periphyton, affects velocity magnitude and shape of vertical profiles, especially in the sloughs where Utricularia spp. and periphyton mats are more abundant. Plot clearing experiments suggest that the presence of surface periphyton and Utricularia exert greater control over flow characteristics than the identity (i.e., sawgrass or spike rush) or density of emergent macrophytes, two parameters frequently incorporated into models describing flow through vegetated canopies. Based on these results, we suggest that future modeling efforts must take the presence of floating biomass, such as Utricularia, and presence of periphyton into consideration when describing particulate transport.

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In 2009, South American military spending reached a total of $51.8 billion, a fifty percent increased from 2000 expenditures. The five-year moving average of arms transfers to South America was 150 percent higher from 2005 to 2009 than figures for 2000 to 2004.[1] These figures and others have led some observers to conclude that Latin America is engaged in an arms race. Other reasons, however, account for Latin America’s large military expenditure. Among them: Several countries have undertaken long-prolonged modernization efforts, recently made possible by six years of consistent regional growth.[2] A generational shift is at hand. Armed Forces are beginning to shed the stigma and association with past dictatorial regimes.[3] Countries are pursuing specific individual strategies, rather than reacting to purchases made by neighbors. For example, Brazil wants to attain greater control of its Amazon rainforests and offshore territories, Colombia’s spending demonstrates a response to internal threats, and Chile is continuing a modernization process begun in the 1990s.[4] Concerns remain, however: Venezuela continues to demonstrate poor democratic governance and a lack of transparency; neighbor-state relations between Colombia and Venezuela, Peru and Chile, and Bolivia and Paraguay, must all continue to be monitored; and Brazil’s military purchases, although legitimate, will likely result in a large accumulation of equipment.[5] These concerns can be best addressed by strengthening and garnering greater participation in transparent procurement mechanism.[6] The United States can do its part by supporting Latin American efforts to embrace the transparency process. _________________ [1] Bromley, Mark, “An Arms Race in Our Hemisphere? Discussing the Trends and Implications of Military Expenditures in South America,” Brookings Institution Conference, Washington, D.C., June 3rd, 2010, Transcript Pgs. 12,13, and 16 [2] Robledo, Marcos, “The Rearmament Debate: A Chilean Perspective,” Power Point presentation, slide 18, 2010 Western Hemisphere Security Colloquium, Miami, Florida, May 25th-26th, 2010 [3] Yopo, Boris, “¿Carrera Armamentista en la Regiόn?” La Tercera, November 2nd, 2009, http://www.latercera.com/contenido/895_197084_9.shtml, accessed October 8th, 2010 [4] Walser, Ray, “An Arms Race in Our Hemisphere? Discussing the Trends and Implications of Military Expenditures in South America,” Brookings Institution Conference, Washington, D.C., June 3rd, 2010, Transcript Pgs. 49,50,53 and 54 [5] Ibid., Guevara, Iñigo, Pg. 22 [6] Ibid., Bromley, Mark, Pgs. 18 and 19

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Catalog of an exhibition held at the Art Museum at Florida International University. Essay by Jed Perl. Organized by Dahlia Morgan.

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In the current managed Everglades system, the pre-drainage, patterned mosaic of sawgrass ridges, sloughs and tree islands has been substantially altered or reduced largely as a result of human alterations to historic ecological and hydrological processes that sustained landscape patterns. The pre-compartmentalization ridge and slough landscape was a mosaic of sloughs, elongated sawgrass ridges (50-200m wide), and tree islands. The ridges and sloughs and tree islands were elongated in the direction of the water flow, with roughly equal area of ridge and slough. Over the past decades, the ridge-slough topographic relief and spatial patterning have degraded in many areas of the Everglades. Nutrient enriched areas have become dominated by Typha with little topographic relief; areas of reduced flow have lost the elongated ridge-slough topography; and ponded areas with excessively long hydroperiods have experienced a decline in ridge prevalence and shape, and in the number of tree islands (Sklar et al. 2004, Ogden 2005).

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Hydrologic modifications have negatively impacted the Florida Everglades in numerous significant ways. The compartmentalization of the once continuously flowing system into the Water Conservation Areas (WCAs) caused disruption of the slow natural flow of water south from Lake Okeechobee through the Everglades to Florida Bay. The ponding of water in the WCAs, the linking of water flow to controlled water levels, and the management of water levels for anthropogenic vs. ecological well-being has caused a reduction in the spatial heterogeneity of the Everglades leading to greater uniformity in topography and vegetation. These effects are noticeable as the degradation in structure of the Everglades Ridge and Slough environment and associated Tree Islands. In aquatic systems water flow is of fundamental importance in shaping the structure and function of the ecosystem. The organized patterns of parallel orientation of ridges, sloughs, and tear-drop shaped tree islands along historic flow paths attest to the importance of water movement in structuring this system. Our main objective was to operate and manage the LILA facility to provide a broad potential as a research platform for an integrated group of multidisciplinary, multi-agency scientists collaborating on multifunctional studies aimed primarily at determining the effects of CERP water management scenarios on the ecology of tree islands and ridge and slough habitats. We support Everglades water management, CERP, and the Long-Term Plan by defining hydrologic regimes that sustain healthy tree islands and ridge and slough ecosystems. Information gained through this project will help to reduce the uncertainty of predicting the tree island and ridge and slough ecosystem response to changes in hydrologic conditions. Additionally, we have developed the LILA site as a visual example of Everglades restoration programs in action.

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In the southern Everglades, vegetation in both the marl prairie and ridge and slough landscapes is sensitive to large-scale restoration activities associated with the Comprehensive Everglades Restoration Plan (CERP) authorized by the Water Resources Development Act (WRDA) 2000 to restore the south Florida ecosystem. More specifically, changes in hydrologic regimes at both local and landscape scales are likely to affect vegetation composition along marl prairie-slough gradient resulting in a shift in boundary between plant communities in these landscapes. To strengthen our ability to assess how vegetation would respond to changes in underlying ecosystem drivers along the gradient, an improved understanding of reference conditions of plant community structure and function, and their responses to major stressors is important. In this regard, a study of vegetation structure and composition in relation to physical and biological processes along the marl prairie-slough gradient was initiated in 2005, and has continued through 2012 with funding from US Army Corps of Engineers (USACOE) (Cooperative Agreement # W912HZ-09-2-0018 Modification No.: P00002). This study addresses the hypothesis with respect to RECOVER-MAP monitoring item 3.1.3.5 – “Marl Prairie/Slough Gradients; patterns and trends in Shark Slough marshes and associated marl prairies”.

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Two protected areas: Royal Bardia National Park (RBNP) and Royal Suklaphanta Wildlife Reserve (RSWR) in the Western Terai, Nepal, are under threats due to present political turmoil, uncontrolled immigration, inefficient land reform policies and unsustainable resource use. I did a stratified random questionnaire survey of 234 households to determine how resource use patterns and problems influence conservation attitudes. Chi-square, Student's t, Mann-Whitney and Kruskal-Wallis tests, and multiple regression were used. There was spatio-temporal variability in resource use patterns and dependency. People were collecting eight and seven types of resources in RBNP and RSWR, respectively. However, people in RBNP were more dependent on resources than RSWR. In both areas, the problem of firewood is serious. The mean attitude score of RBNP (8.4 ± 1.44) was significantly higher than the score of RSWR (7.7 ± 1.66; t = 3.24, p = 0.0007). Conservation attitude was determined by variables such as participation in trainings, wildlife damage, and satisfaction towards user groups.

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The missile's significance has been central to national security since the Soviet launching of Sputnik, and became increasingly important throughout the years of the Cold War. Much has been written about missile technology, but little has been written about how the development and deployment of this weapon affected Americans. The missile was developed to both deter war but also to win war. Its presence, however, was not always reassuring. Three areas of the United States are studied to evaluate the social implications of the missile during these pivotal years: San Francisco, home of multiple Nike installations; of Cape Canaveral, Florida, the nation's primary missile test center; the Great Plains, the location of the largest ICBM concentration in the country. Interviews were conducted, tours of facilities were taken, and local newspapers were reviewed. In conjunction with national newspapers and magazines and public opinion polls, this information provided a local social context for missile history. Nationally and locally, Americans both feared and praised the new technology. They were anxious for government funding in their cities and often felt that the danger the missile brought to their communities by making it as a Soviet target was justified in the larger cause for national security.

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Classification procedures, including atmospheric correction satellite images as well as classification performance utilizing calibration and validation at different levels, have been investigated in the context of a coarse land-cover classification scheme for the Pachitea Basin. Two different correction methods were tested against no correction in terms of reflectance correction towards a common response for pseudo-invariant features (PIF). The accuracy of classifications derived from each of the three methods was then assessed in a discriminant analysis using crossvalidation at pixel, polygon, region, and image levels. Results indicate that only regression adjusted images using PIFs show no significant difference between images in any of the bands. A comparison of classifications at different levels suggests though that at pixel, polygon, and region levels the accuracy of the classifications do not significantly differ between corrected and uncorrected images. Spatial patterns of land-cover were analyzed in terms of colonization history, infrastructure, suitability of the land, and landownership. The actual use of the land is driven mainly by the ability to access the land and markets as is obvious in the distribution of land cover as a function of distance to rivers and roads. When considering all rivers and roads a threshold distance at which disproportional agro-pastoral land cover switches from over represented to under represented is at about 1km. Best land use suggestions seem not to affect the choice of land use. Differences in abundance of land cover between watersheds are more prevailing than differences between colonist and indigenous groups.

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1. nowhere landscape, for clarinets, trombones, percussion, violins, and electronics

nowhere landscape is an eighty-minute work for nine performers, composed of acoustic and electronic sounds. Its fifteen movements invoke a variety of listening strategies, using slow change, stasis, layering, coincidence, and silence to draw attention to the sonic effects of the environment—inside the concert hall as well as the world outside of it. The work incorporates a unique stage set-up: the audience sits in close proximity to the instruments, facing in one of four different directions, while the musicians play from a number of constantly-shifting locations, including in front of, next to, and behind the audience.

Much of nowhere landscape’s material is derived from a collection of field recordings

made by the composer during a road trip from Springfield, MA to Douglas, WY along US- 20, a cross-country route made effectively obsolete by the completion of I-90 in the mid- 20th century. In an homage to artist Ed Ruscha’s 1963 book Twentysix Gasoline Stations, the composer made twenty-six recordings at gas stations along US-20. Many of the movements of nowhere landscape examine the musical potential of these captured soundscapes: familiar and anonymous, yet filled with poignancy and poetic possibility.

2. “The Map and the Territory: Documenting David Dunn’s Sky Drift”

In 1977, David Dunn recruited twenty-six musicians to play his work Sky Drift in the

Anza-Borrego Desert in Southern California. This outdoor performance was documented with photos and recorded with four stationary microphones to tape. A year later, Dunn presented the work in New York City as a “performance/documentation,” playing back the audio recording and projecting slides. In this paper I examine the consequences of this kind of act: what does it mean for a recording of an outdoor work to be shared at an indoor concert event? Can such a complex and interactive experience be successfully flattened into some kind of re-playable documentation? What can a recording capture and what must it exclude?

This paper engages with these questions as they relate to David Dunn’s Sky Drift and to similar works by Karlheinz Stockhausen and John Luther Adams. These case-studies demonstrate different solutions to the difficulty of documenting outdoor performances. Because this music is often heard from a variety of equally-valid perspectives—and because any single microphone only captures sound from one of these perspectives—the physical set-up of these kind of pieces complicate what it means to even “hear the music” at all. To this end, I discuss issues around the “work itself” and “aura” as well as “transparency” and “liveness” in recorded sound, bringing in thoughts and ideas from Walter Benjamin, Howard Becker, Joshua Glasgow, and others. In addition, the artist Robert Irwin and the composer Barry Truax have written about the conceptual distinctions between “the work” and “not- the-work”; these distinctions are complicated by documentation and recording. Without the context, the being-there, the music is stripped of much of its ability to communicate meaning.

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Background: Too little information is available on Sri Lanka’s current capacity to provide community genetic services—antenatal genetic services in particular—to understand whether building that capacity could further improve and reduce disparity in maternal and child health. This qualitative research project seeks to gather information on congenital disorders, routine antenatal care, and the current state of antenatal screening testing services within that routine antenatal to assess the feasibility of and the need for scaling up antenatal genetics services in Sri Lanka. Methods: Nineteen key informant (KI) interviews were conducted with stakeholders in antenatal care and genetic services. Seven focus group discussions were held with a total of 56 Public Health Midwives (PHMs), the health workers responsible for antenatal care at the field level. Transcripts for all interviews and FGDs were analyzed for key themes, and themes were categorized to address the specific aims of the project. Results: Antenatal genetic services play a minor role in antenatal care, with screening and diagnostic procedures available in the private sector and paid for out-of-pocket. KIs and PHMs expect that demand for antenatal genetic services will increase as patients’ purchasing power and knowledge grow but note that prohibitive abortion laws limit the ability of patients to act on test results. Genetic services compete for limited financial and human resources in the free public health system, and inadequate information on the prevalence of congenital disorders limits the ability to understand whether funding for services related to those disorders should be increased. A number of alternatives to scaling up antenatal genetic services within the free health system might be better suited to the Sri Lankan structural and social context. Conclusions: Scaling up antenatal genetic services within the public health system is not feasible in the current financial, legal, and human resource context. Yet current availability and utilization patterns contribute to regional and economic disparities, suggesting that stasis will not bring continued improvements in maternal and child health. More information on the burden of congenital disorders is necessary to fully understand if and how antenatal genetic service availability should be increased in Sri Lanka, but even before that information is gathered, examination of policies for patient referral, termination of pregnancy, and government support for individuals with genetic disease are steps that might bring extend improvements and reduce disparity in maternal and child health.

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A high proportion of amphibian species are threatened with extinction globally, and habitat loss and degradation are the most frequently implicated causes. Rapid deforestation for the establishment of agricultural production is a primary driver of habitat loss in tropical zones where amphibian diversity is highest. Land-cover change affects native assemblages, in part, through the reduction of habitat area and the reduction of movement among remnant populations. Decreased gene flow contributes to loss of genetic diversity, which limits the ability of local populations to respond to further environmental changes. The focus of this dissertation is on the degree to which common land uses in Sarapiquí, Costa Rica impede the movement of two common amphibian species. First, I used field experiments, including displacement trials, and a behavioral landscape ecology framework to investigate the resistance of pastures to movement of Oophaga pumilio. Results from experiments demonstrate that pastures do impede movement of O. pumilio relative to forest. Microclimatic effects on movement performance as well as limited perceptual ranges likely contribute to reduced return rates through pastures. Next, I linked local processes to landscape scale estimates of resistance. I conducted experiments to measure habitat-specific costs to movement for O. pumilio and Craugastor bransfodrii, and then used experimental results to parameterize connectivity models. Model validation indicated highest support for resistance estimates generated from responses to land-use specific microclimates for both species and to predator encounters for O. pumilio. Finally, I used abundance and experiment-derived resistance estimates to analyze the effects of prevalent land uses on population genetic structure of the two focal species. While O. pumilio did not exhibit a strong response to landscape heterogeneity and was primarily structured by distances among sites, C. bransfordii genetic variation was explained by resistance estimates from abundance and experiment data. Collectivity, this work demonstrates that common land uses can offer different levels of resistance to amphibian movements in Sarapiquí and illustrates the value of investigating local scales processes to inform interpretation of landscape-scale patterns.

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Thesis (Master's)--University of Washington, 2016-08

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Thesis (Ph.D.)--University of Washington, 2016-08