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51.
Local knowledge is a valuable asset in observing and managing environmental change, and importantly, is an unheralded source of adaptive capacity. Torres Strait Islanders are no exception, having used such knowledge to adapt to biophysical changes in their environment for centuries. This article explores the ways in which Islanders have coped in the past with environmental changes to plan for their future. This article focuses on Erub Island in the eastern group of islands in the Torres Strait and charts the adaptation actions or activities employed by respected locals (Elders and Aunties). Drawing on their local knowledge, these actions or activities have included the building of rock walls and wind breaks, using native species to re-vegetate sand cays and the coastal foreshore, applying self-sufficient practices such as fish traps and gardening, reading and respecting country, and transferring this knowledge to the younger generation. In this way, it is the Islanders themselves who detail, based on their local knowledge, what is most appropriate for their community.  相似文献   
52.
The development, testing, and application of a probabilistic model framework for the light attenuation coefficient for downwelling irradiance (Kd) and Secchi disc transparency (SD) that resolves the effects of several light attenuating constituents, including phytoplankton and nonliving particles (tripton), is documented. The model is consistent with optical theory, partitioning the magnitudes of the light attenuating processes of absorption and scattering according to the contributions of attenuating constituents as simple summations. The probabilistic framework accommodates variations in the character and concentrations of these constituents and ambient conditions during measurements, and recognizes a linear relationship between the magnitudes of absorption and scattering by tripton. The model is tested and applied for a 21 km reach of the Seneca River, New York, that features optical gradients caused by an intervening hypereutrophic lake and dam, and a severe infestation of the exotic zebra mussel. The model is applied to resolve the roles of phytoplankton and tripton in regulating measured longitudinal patterns of SD along the study reach of the river and increases in SD since the zebra mussel invasion, and to predict decreases in Kd since the invasion.  相似文献   
53.
In the period of transition from communism, the countries of central and eastern Europe have made considerable efforts to adopt new environmental legislation and to create new institutions. However, the implementation of these powers, particularly at the level of local government, remains problematic. This article reviews the arguments for developing capacity for taking environmental action at the municipal level, and then examines the actual experience of one such country, the Slovak Republic. While Slovakia displays many of the features of policy making familiar to other transitional countries, it has faced some particular political problems. Recent legislation has given formal competencies in the field of environmental protection to local government, but it remains fragmented and relatively poorly resourced. Nevertheless, there is evidence that, through a combination of mutual support through national associations and the establishment of international links, local authorities are adopting a number of innovative approaches and strategies which should be better able to address the changing character of environmental problems.  相似文献   
54.
ABSTRACT This paper examines the social impact of reservoir construction on a rural community group located in the urban fringe of a major metropolitan area in central Ohio. The study data were collected at three intervals over a ten-year period (1970, 1974, 1980). Evaluation of resident opinions in the affected community revealed significant attitude differences over time for four of the five variables measured. The findings revealed that the study group desired more social stability but had accommodated the changes experienced to date. Responses to the attitude scales showed that the people in the study group were well integrated and were closely identified with each other at all three test periods. Attitudes toward the lake project were significantly more positive over time, and in 1980 the collective community group held a basically neutral attitude about the lake. The development agency was also perceived more positively over time.  相似文献   
55.
Macroinvertebrates were examined on an impounded valley marsh in Stonington, Connecticut, that has changed from aTypha-dominated system to one with typical salt-marsh vegetation during 13 years following the reintroduction of tidal exchange. Animal populations on this restored impounded marsh were evaluated by comparing them with populations on a nearby unimpounded valley marsh of roughly the same size. Populations of the high marsh snail,Melampus bidentatus Say, were quantitatively sampled along transects that extended from the water-marsh edge to the upland; those of the ribbed mussel,Geukensia demissa Dillwyn, were sampled in low marsh areas on transects along the banks of creeks and mosquito ditches. The occurrence of other marsh invertebrates also was documented, but their abundance was not measured. The mean density ofMelampus was 332±39.6 SE/m2 on the restored impounded marsh and 712±56.0 SE/m2 on the unimpounded marsh. However, since snails were larger on the restored impounded marsh, the difference in snail biomass was less pronounced than the difference in snail density. MeanMelampus biomass was 4.96±0.52 SE g dry wt/m2 on the restored impounded marsh and 6.96±0.52 SE g dry wt/m2 on the unimpounded marsh. On the two marshes, snail density and biomass varied in relation to plant cover and other factors. The density and biomass ofGeukensia at the edge of the marsh were comparable on the restored impounded and unimpounded marshes. Mean mussel densities ranged from 80 to 240/m2 and mean mussel biomass varied from 24.8–64.8 g dry wt/m2 in different low marsh areas. In contrast, below the impoundment dike, meanGeukensia density was 1100±96.4 SE/m2 and meanGeukensia biomass was 303.6±33.28 SE g dry wt/m2. A consideration of all available evidence leads to the conclusion that the impounded marsh is in an advanced phase of restoration.  相似文献   
56.
South Korea’s Civilian Control Zone (CCZ), a relatively untouched area due to tight military oversight since the end of Korean War, has received considerable attention nationally and internationally for its rich biodiversity. However, the exclusion of local communities from the process of defining problems and goals and of setting priorities for biodiversity conservation has halted a series of biodiversity conservation efforts. Through qualitative research, we explored CCZ farmers’ views of key problems and issues and also the sources of their opposition to the government-initiated conservation approaches. Key findings include the farmers’ concerns about the impact of conservation restrictions on their access to necessary resources needed to farm, wildlife impacts on the value of rice and other agricultural goods they produce, and farmers’ strong distrust of government, the military, and planners, based on their experiences with past conservation processes. The findings regarding farmers’ perceptions should prove useful for the design of future participatory planning processes for biodiversity conservation in the CCZ. This case highlights how conservative measures, perceived to be imposed from above—however scientifically valuable—can be undermined and suggests the value that must be placed on communication among planners and stakeholders.  相似文献   
57.
Abstract: Knowledge of headwater influences on the water‐quality and flow conditions of downstream waters is essential to water‐resource management at all governmental levels; this includes recent court decisions on the jurisdiction of the Federal Clean Water Act (CWA) over upland areas that contribute to larger downstream water bodies. We review current watershed research and use a water‐quality model to investigate headwater influences on downstream receiving waters. Our evaluations demonstrate the intrinsic connections of headwaters to landscape processes and downstream waters through their influence on the supply, transport, and fate of water and solutes in watersheds. Hydrological processes in headwater catchments control the recharge of subsurface water stores, flow paths, and residence times of water throughout landscapes. The dynamic coupling of hydrological and biogeochemical processes in upland streams further controls the chemical form, timing, and longitudinal distances of solute transport to downstream waters. We apply the spatially explicit, mass‐balance watershed model SPARROW to consider transport and transformations of water and nutrients throughout stream networks in the northeastern United States. We simulate fluxes of nitrogen, a primary nutrient that is a water‐quality concern for acidification of streams and lakes and eutrophication of coastal waters, and refine the model structure to include literature observations of nitrogen removal in streams and lakes. We quantify nitrogen transport from headwaters to downstream navigable waters, where headwaters are defined within the model as first‐order, perennial streams that include flow and nitrogen contributions from smaller, intermittent and ephemeral streams. We find that first‐order headwaters contribute approximately 70% of the mean‐annual water volume and 65% of the nitrogen flux in second‐order streams. Their contributions to mean water volume and nitrogen flux decline only marginally to about 55% and 40% in fourth‐ and higher‐order rivers that include navigable waters and their tributaries. These results underscore the profound influence that headwater areas have on shaping downstream water quantity and water quality. The results have relevance to water‐resource management and regulatory decisions and potentially broaden understanding of the spatial extent of Federal CWA jurisdiction in U.S. waters.  相似文献   
58.
ABSTRACT: Alum treatment of a shallow lake, with mean depth 2 m and area 137 ha, curtailed internal loading of P for at least one ear. Mean summer total P and chl a decreased from 76 and 27μg l?1, respectively, in 1978 before treatment. to 29 and 14 μ l?1, while mean summer Sed transparency increased from 1.6 to 2.2 m and blue green algae were no longer dominant. Macrophyte biomass and distribution retuned during the post-alum year, 1980-1981, to previous levels after a 1979 four-month lake level drawdown had reduced biomass by 84 percent The improved transparency, resulting from the decrease in chl a following treatment, could encourage greater biomass of macrophytes in the deeper area of the lake. Recovery of macrophyte biomass to predrawdown levels may restore internal loading of P through enrichment of deep water sediments during winter dieback and decomposition.  相似文献   
59.
Because environmental conservation can remove scarce natural resources from competing uses, it is important to gain support for conservation programs by demonstrating that management actions have been effective in achieving their goals. One way to do this is to show that selected significant environmental variables (indicators) vary between managed and unmanaged areas or change over time following implementation of a management regime. However, identifying indicators that reflect environmental conditions relevant to management practices has proven difficult. This paper focuses on developing a framework for choosing indicators in a coral reef habitat. The framework consisted of three phases: (1) information gathering to identify candidate variables; (2) field-testing candidate variables at sites that differ in intensity of human activity, thus identifying potential indicators; and (3) evaluating potential indicators against a set of feasibility criteria to identify the most useful indicators. To identify indicators suitable to measure the success of a management strategy to reduce anchor damage to a coral reef, 24 candidate variables were identified and evaluated at sites with different intensities of anchoring. In this study, measures that reflected injuries to coral colonies were generally more efficient than traditional measures of coral cover in describing the effects of anchoring. The number of overturned colonies was identified as the single most useful indicator of coral reef condition associated with anchoring intensities. The indicator selection framework developed here has the advantages of being transparent, cost efficient, and readily transferable to other types of human activities and management strategies.  相似文献   
60.
Few disputes in the annals of US environmentalism enjoy the pedigree of the conservation-preservation debate. Yet, although many scholars have written extensively on the meaning and history of conservation and preservation in American environmental thought and practice, the resonance of these concepts outside the academic literature has not been sufficiently examined. Given the significance of the ideals of conservation and preservation in the justification of environmental policy and management, however, we believe that a more detailed analysis of the real-world use and understanding of these ideas is needed. In this paper, we describe the results of a qualitative, semantic study of the concepts of conservation and preservation undertaken in the context of the Chattahoochee National Forest (CNF), located in northern Georgia (USA). Thirty in-depth interviews were conducted with scientists and north Georgia residents either interested or involved in the future management of the forest. Respondents were asked to define conservation and preservation in their own words and to indicate which approach they felt was more appropriate for the management of the CNF. Qualitative content analysis was used to elicit a set of recurring themes for each foundational concept. Taken together, these themes help to flesh out the meaning of conservation and preservation for citizens and scientists today, and illustrate the evolving nature of two of the more significant and venerable ideas animating US environmental policy and management.  相似文献   
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