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This article examines roles, opportunities, and challenges for Indigenous land management in rapidly developing landscapes through a case study of Bunya Bunya Country Aboriginal Corporation, a not-for-profit organization on the Sunshine Coast, Queensland, Australia. An analysis of data collected through semistructured interviews, participant observation, and analysis of secondary sources reveals that Aboriginal land managers work in a variety of roles to manage issues affecting the local environment and cultural heritage sites. These efforts are challenged by the absence of Native Title and colonial land management policies, which restrict Aboriginal involvement in land management. We conclude that there is a need for alternative pathways to engage with Aboriginal land managers who cannot, or choose not to, proceed with Native Title. Decolonized decision-making tools and sustainable enterprises are viable opportunities that partially address these challenges and could deliver tangible socio-economic and cultural benefits to local Aboriginal and non-Aboriginal people.  相似文献   
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This paper will discuss the use of chemical proxies in coral skeletons to reconstruct the history of salinity (from the δ18O of the skeleton) and nutrients in the water (from the δ13C) in Florida Bay between 1824 and 1994. Monthly salinity and water temperature data collected since 1989 were used to establish a correlation between salinity, temperature, and the δ18O of the skeleton of the coralSolenastrea bournoni from Lignumvitae Basin in Florida Bay. This relationship explains over 50% of the variance in the δ18O of the skeleton. Assuming that interannual variations in the temperature of the water are small, we have applied this relationship to the δ18O measured in the coral skeleton collected from Lignumvitae Basin which has a record between 1824 and 1993. These data provide a revised estimate of salinity variation in Lignumvitae Basin for the period when historical records for salinity were not available, and show that the highest salinity events occurred in the past 30 yr. Using the relationships between the salinity in Lignumvitate Basin and other basins, obtained using a modern dataset, we are able to estimate ranges in salinity for other portions of Florida Bay. Skeletons of specimens of the coral speciesSiderastrea radians collected from other areas of Florida Bay show similar patterns in the δ18O over the past 10 yr, indicating that corals in most portions of Florida Bay are recording salinity variations in their skeletons and therefore support the idea that salinity variations in different portions of Florida Bay can be related. Fluorescence analysis of the coral from Lignumvitae Basin shows a large change in the magnitude of the 10-yr signal coincident with the construction of the railway, confirming that this event had a significant impact upon Florida Bay. The δ13C of the coral skeletons reveals a long-term history of the oxidation of organic material, fixation of carbon by photosynthesis (algal blooms), and the intrusion of marine water into the bay. Since the construction of the railway from Miami to Key West there has been a long-term decrease in the δ13C of the coral skeleton from Lignumvitae Basin, suggesting the increased oxidation of organic material in this area. This decrease in δ13C appears to have reached a minimum value around 1984 and has increased since this time in the western portions of Florida Bay. The increase may be related to the algal blooms prevalent in the area or alternatively could result from intrusion of more marine water. In the eastern areas, a small increase in the δ18C between 1984 and 1988 was followed by further decline suggesting more oxidation of organic material. We have also attempted to use the concentration of barium in the coral skeleton as a proxy indicator of the nutrient status in Florida Bay.  相似文献   
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Mitigation of lunar dust adhesion by surface modification   总被引:2,自引:0,他引:2  
Dust has been recognized as one of the greatest hazards in continued lunar exploration due to its tenacious adhesion to everything with which it comes into contact. Unfortunately, there is little known about the mechanisms of adhesion on widely varying surface types: van der Waals and electrostatic forces are the dominant forces under consideration here. Surface energy, roughness, mechanical properties and electronic properties are all known to contribute to the adhesion characteristics. An optimal solution to mitigate dust adhesion would be to identify the dominant components of the adhesive force and to reduce that force by surface modification. In this study, an ion beam process was used to modify (treat) the surfaces of three dramatically different materials spanning the range of conductor (black Kapton), semiconductor (silicon), and insulator (quartz). Adhesive forces between less than JSC-1 lunar simulants and these virgin/treated surfaces were measured in vacuum using a centrifugal force detachment method. We found that JSC-1 particles adhered less to treated silicon and quartz surfaces, correlated with a reduction in van der Waals force due to a reduced surface energy. The large reduction in adhesion for treated black Kapton is mainly due to the large decrease in the electrostatic (image) force that results from reduced contact charging. Materials in space and on the lunar surface will be directly exposed to high-energy ultraviolet radiation prior to being covered by dust, so the UV irradiation effects on surface adhesion were also examined. Both virgin and treated quartz surfaces are most affected by the UV-irradiation, showing dramatically increased adhesion.  相似文献   
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A research agenda is currently developing around the linkages between ecosystem services and poverty alleviation. It is therefore timely to consider which conceptual frameworks can best support research at this nexus. Our review of frameworks synthesises existing research on poverty/environment linkages that should not be overlooked with the adoption of the topical language of ecosystem services. A total of nine conceptual frameworks were selected on the basis of relevance. These were reviewed and compared to assess their ability to illuminate the provision of ecosystem services, the condition, determinants and dynamics of poverty, and political economy factors that mediate the relationship between poverty and ecosystem services. The paper synthesises the key contributions of each of these frameworks, and the gaps they expose in one another, drawing out lessons that can inform emerging research. Research on poverty alleviation must recognize social differentiation, and be able to distinguish between constraints of access and constraints of aggregate availability of ecosystem services. Different frameworks also highlight important differences between categories of services, their pathways of production, and their contribution to poverty alleviation. Furthermore, we highlight that it is important to acknowledge the limits of ecosystem services for poverty alleviation, given evidence that ecosystem services tend to be more associated with poverty prevention than reduction. We conclude by reflecting on the relative merits of dynamic Social–Ecological Systems frameworks versus more static checklists, and suggest that research on ecosystem services and poverty alleviation would be well served by a new framework distilling insights from the frameworks we review.  相似文献   
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Landcare groups in Australia work to increase biodiversity, eliminate invasive species and promote sustainable land-use practices. With the implementation of the Rudd government's ‘Caring for our Country’ policy during 2008–09, financial and organisational resources available to these groups diminished. This paper examines whether the National Landcare Program's initial intentions—that agency support could be provided to ‘kick-start’ the community groups into action with the Landcare groups quickly becoming independent bodies—are ultimately realistic. The results show that the majority of Landcare groups continue to be reliant on government-sourced funding and Landcare facilitators, and that those groups which do not have access to support have reduced their activity levels accordingly. Landcare groups were suffering from a reduced volunteer base, with static or decreasing numbers of participants, an inability to set regular meetings and a lack of volunteers to take up leadership positions. The reliance of Landcare groups on government support suggests that Landcare was an unsuccessful form of state-sponsored community participation, making Landcare groups similar to other volunteer organisations in terms of their functional characteristics and reliance on externally sourced funds.  相似文献   
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Concentration‐discharge (c‐Q) plots are routinely used as an integrated signal of watershed response to infer solute sources and travel pathways. However, the interpretation of c‐Q data can be difficult unless these data are fitted using statistical models. Such models are frequently applied for geogenic solutes, but it is unclear to what extent they might aid in the investigation of nutrient export patterns, particularly for total dissolved phosphorus (TDP) which is a critical driver of downstream eutrophication problems. The goal of the present study was therefore to statistically model c‐Q relations (where c is TDP concentrations) in a set of contrasting watersheds in the Northern Great Plains—ranging in size from 0.2 to 1000+ km2—to assess the controls of landscape properties on TDP transport dynamics. Six statistical models were fitted to c‐Q data, notably (a) one linear model, (b) one model assuming that c‐Q relations are driven by the mixing of end‐member waters from different landscape locations (i.e., hydrograph separation), (c) one model relying on a biogeochemical stationarity hypothesis (i.e., power law), (d) one model hypothesizing that c‐Q relations change as a function of the solute subsurface contact time (i.e., hyperbolic model), and (e) two models assuming that solute fluxes are mostly dependent on reaction rates (i.e., chemical models). Model performance ranged from mediocre (R2 < 0.2) to very good (R2 > 0.9), but the hydrograph separation model seemed most universal. No watershed was found to exhibit chemostatic behaviour, but many showed signs of dilution or enrichment behaviour. A tendency toward a multi‐model fit and better model performance was observed for watersheds with moderate slope and higher effective drainage area. The relatively poor model performance obtained outside these conditions illustrates the likely importance of controls on TDP concentrations in the region that are independent of flow dynamics.  相似文献   
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