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In the late 1980s, a collaborative effort between Harvard University’s Lower Mississippi Survey and Tulane University’s Center for Archaeology launched a study examining the causes and consequences of subsistence change in the Lower Mississippi Valley. The Osceola Project contributed the first formal study of late prehistoric faunal remains within the Alluvial Plain, becoming the standard against which all subsequent Coles Creek faunal assemblages have been measured. Recent evidence recovered from three sites located in the Eastern Uplands presented the opportunity to compare and contrast vertebrate subsistence in these two distinct physiographic regions. We hypothesize that a clear distinction exists between lowland and upland Coles Creek procurement strategies. This article evaluates this claim by examining species diversity, spatial patterns, and temporal trends evident within an eight-site sample. The results suggest that the primary factor influencing Coles Creek fauna procurement was the immediate environment, and that the composition of Late Woodland period diets may be a reflection of efficiency of effort rather than food access or scarcity.  相似文献   
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This study uses service area–based coverage and various count regression methods to assess neighbourhood-level healthy and unhealthy food environments, and food access associated with different socio-economic groups in Edmonton, Canada. We identify three types of vulnerable neighbourhoods according to different food environments: food deserts (i.e., neighbourhoods lack sufficient access to healthy foods); food swamps (i.e., neighbourhoods have excess access to unhealthy foods); and those with overlaps of food swamps and food deserts. We also identify neighbourhoods with superior access to healthy foods (i.e., food oases). Additionally, our results from regression analyses indicate: (1) child population is negatively associated with both healthy and unhealthy food resources; (2) good access to public transportation is associated with good coverage of all healthy food outlets and convenience stores; and (3) deprived neighbourhoods with higher percentages of minority populations have better coverage of both healthy and unhealthy foods in general. The results from this study can help the City of Edmonton identify the key neighbourhoods with high potential for local business and the hotspot neighbourhoods that require particular support. Tailored strategies are proposed to effectively and efficiently improve food environments with limited resources.  相似文献   
3.
Wetlands are common in Coastal Western Hemlock forests yet the hydrologic processes that generate runoff from small swamps are not completely understood. Direct field observations, hydrologic, and electrical conductivity data were collected from a gently sloping forested swamp complex from July to November 2009. Swamps occupied depressions between raised mounds (0.1 to 3 m high) and were connected by an ephemeral creek. Runoff was controlled by antecedent moisture conditions and influenced by basin microtopography. Two hydrologic regimes occurred during the study period and different runoff processes dominated each regime. Runoff was generated by subsurface flow during dry antecedent conditions as swamps remained hydrologically disconnected from each other. Runoff was generated by surface outflow from hydrologically connected swamps during wet antecedent conditions as ponded water spilled out of the depressions. The forested swamp complex produced a faster but limited hydrologic response during dry antecedent conditions compared to a slower but greater hydrologic response during wet antecedent conditions. Stormwater runoff and runoff ratios were up to two orders of magnitude higher in wet conditions than during similarly sized events in dry conditions. These factors should be considered when designing monitoring programs or runoff models in forested swamps with significant microtopography. Field surveys and estimates of hydrologic inputs and outputs may be useful in predicting the potential hydrologic connectivity of isolated forested swamps.  相似文献   
4.
Geomorphology, geochronology and palynology are used to assess the development and stability of two channelled swamps on the Barrington Tops plateau. While both swamps commenced peat accumulation prior to about 4000 cal BP, new stratigraphic data indicate incision between 700 and 1000 cal BP, in response to regional climate change. Two broad stratigraphic units are identified in each swamp: the upper floodplain, comprised entirely of peat, and the inset floodplain, underlain by interbedded peat and fluvial sediments. Following incision, rapid vertical growth of the inset floodplain occurred on the Barrington River between 690 and 620 cal BP, and palynological data indicate a change from more saturated pre‐incision swamp flora to less saturated post‐incision swamp flora. Bankfull stage‐height, achieved many times in a year, is remarkably consistent along the length of each swamp channel. Its elevation controls the overall elevation of the swamps by controlling the height of the water‐table and hence the growth of swamp vegetation and formation of peat. In particular, contemporary channel dimensions control the growth and height of the inset floodplain, a process that results in the formation of an organic floodplain not previously described in the geomorphic literature.  相似文献   
5.
The Blue Mountains region of New South Wales, including the World Heritage listed Blue Mountains National Park, is arguably one of Australia's most highly valued and iconic wilderness areas. Common to this region are upland swamps (formally ‘temperate highland peat swamps on sandstone’), which play a vital hydrological role at the headwaters of the river catchments, as well as providing the habitat for an array of flora and fauna species. This paper involves an interdisciplinary examination into the need and potential for adaptive management in the Blue Mountains. It uses geomorphic (physical) knowledge of swamp condition and social data about the volunteers who rehabilitate them. Research involved using the River Styles river condition framework across 47 swamps and questionnaires and interviews with local rehabilitation volunteers. It is proposed that there is a need and a potential to combine geomorphic understanding with further engagement of community volunteers in order to enable an interdisciplinary approach to adaptive management. Such an approach could result in the effective environmental management of upland swamps in the Blue Mountains.  相似文献   
6.
As Vietnam embraces the market economy, and a number of state policies promote reforestation and rural market integration, land use and land cover (LULC) changes are occurring in the country's northern uplands in increasingly complex and fragmented ways. Yet understandings of the degree and consequences of LULC changes in this diverse agro‐ecological region are incomplete. We conduct a systematic literature review of research reported in academic articles tracing and analysing LULC change in Vietnam's northern regions. We find that these studies have tended to take place away from the most mountainous, northern borderlands. The studies nonetheless highlight a diversity of land use land cover changes caused by numerous causes, making the distinction of overall trends difficult. To complement and extend this body of research, we introduce recent LULC change research we have completed in the mountainous border districts of Lào Cai province, on the Sino‐Vietnamese border. The heterogeneity of causes of LULC change in both the review articles and our case study points to the importance of adapting land use policies to local agro‐ecological and socio‐economic conditions and ethnic diversity, taking into account state–farmer relations, household livelihood decision‐making, and policy implementation at the commune and district levels.  相似文献   
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