Interpreting amenities,envisioning the future: common ground and conflict in North Carolina’s rural coastal communities

This paper contributes to ongoing discussions about the implications of rural change and amenity migration for members of diverse rural communities. We engage with recent amenity migration and political ecology literature that focuses on social constructions of nature and landscapes, and how these constructions affect the attitudes and opinions of community members. We use our case study of a mail-based survey in Down East, North Carolina to suggest that the ways in which people conceptualize the particular ‘natures’ and landscapes of a place matters in terms of shaping people’s attitudes with respect to ongoing processes of change. We find that people’s opinions about environment, culture, and land use are often superficially similar but that when conflicts arise or particular actions are considered, substantial differences in people’s underlying conceptual frameworks are revealed. In particular we find that despite widespread shared appreciation of the environment and culture Down East, differing interpretations of these key terms lead to potential misunderstandings and land use planning challenges.     

Determination of Free Cd,Cu and Zn Concentrations in Lake Waters by In Situ Diffusion Followed by Column Equilibration Ion-exchange

Combining in situ diffusion and column ion-exchange equilibration, we measured free metal ion concentrations (Cd, Cu and Zn) in water samples collected from the epilimnion of 14 lakes in the Rouyn-Noranda area (600 km north-west of Montreal, QC, Canada). Lakes were selected to represent a wide range of physico-chemical characteristics (hardness, pH, dissolved organic matter—DOM, degree of metal contamination), to determine the influence of these parameters on metal speciation. Total dissolved metal concentrations, as determined within the diffusion cells, varied over one to two orders of magnitude: [Cd] 0.19–2.9 nM; [Cu] 36–190 nM; [Zn] 7–2,800 nM. The proportion of total dissolved metal present as free Cd²⁺ and Zn²⁺ was relatively constant for the 14 selected lakes, despite the wide pH (4.5–8) and DOM (3–23 mg C/L) ranges, probably reflecting the inverse relationship observed between pH and DOM; this proportion did, however, vary with DOM and pH for Cu. Our experimental free metal ion concentrations were compared with those calculated with the thermodynamic models WHAM (Windermere Humic Aqueous Model VI) and ECOSAT 4.7 (incorporating the NICA-Donnan model). Measured and calculated values were in reasonable agreement for both Cd and Zn although measured values were generally slightly higher, i.e. less than one order of magnitude. For several lakes, measured free Cu concentrations were, however, much higher than the calculated values, suggesting that these models overestimate Cu complexation. The gap between measured and calculated free metal ion concentration becomes more important as the total metal concentration decreases and as pH increases.     

Investigating Climate Change Impacts and Thresholds: An Application of the CLIMPACTS Integrated Assessment Model for New Zealand Agriculture

The determination of `critical thresholds'is an essential task for informed policydecisions on establishing greenhouse gas emissiontargets. This paper presents a framework fordetermining critical thresholds for New Zealandagriculture, focusing on three agriculturalcrops – kiwifruit, grain maize, andPaspalum dilatatum – as exemplars for the fruitproduction, arable cropping and dairy productionindustries in New Zealand. The approach is based onthe application of a country-scale, integratedassessment model, called CLIMPACTS. The CLIMPACTSsystem contains a climate change scenario generator,climate and land data, and sectoral impact models. Importantly, CLIMPACTS allows time-dependentassessments of climate change and its effects, whichfacilitates the identification and examination of thresholds, which largely relate to spatial changes, over time, in regions of economic importance for these crops. However, whether such thresholds are `critical' for New Zealand cannot currently be addressed by the CLIMPACTS model. The determination of `criticality' requires a fully integrated assessment in which the social, economic, and environmental costs and risks associated with these thresholds are comprehensively evaluated.     

苏格兰阿伯丁城市土壤的微生物特性研究

在重金属的胁迫下,阿伯丁城市土壤中微生物特征发生了显著的变化,与农村土相比,微生物基底呼吸作用明显增强,但微生物生物量却显著降低,微生物生理参数Ｃｍｉｎ／Ｃｏｒｇ、ｑＣＯ２值明显升高,Ｂｉｏｌｏｇ数据显示城市土壤对能源碳的消耗量和速度显著升高,而且对能源碳的利用方式发生了改变,但利用效率却明显降低,反映出微生物特性可作为城市土壤环境质量变异的有效指标。     

Co-management of sea turtle fisheries: Biogeography versus geopolitics

Co-management between local communities and government agencies is promoted as a strategy to improve fisheries management. This paper considers the potential for co-management of sea turtle fisheries within four UK Overseas Territories (OTs) in the Caribbean, and for co-ordinated management among those territories. We focus on fisher incentives for engaging in co-management and on the potential to scale up co-management to a regional level. This paper presents data from Anguilla, British Virgin Islands, Montserrat, and Turks and Caicos Islands, where 110 turtle fishers participated in a socio-economic survey undertaken as part of the ‘Turtles in the UK Overseas Territories in the Caribbean’ project. Based on three established criteria for co-management (perceived crisis in stock, willingness to participate and community cohesion), results suggest that fisher support for co-management exists within each OT, but the extent of support for and views of specific management interventions varies among OTs. The implications of results for co-management in each territory, and for establishing co-ordinated management regimes in the region, are discussed in the context of current debates about the nature of resources and scalar (mis)matches between resource and management regimes.     

Measurement of dissolved oxygen using optodes in a FerryBox system

Optode sensors can provide detailed information on concentrations of dissolved oxygen, which in turn may be used to quantify variations in net primary productivity. Throughout 2005 and 2006 the performance of commercially available oxygen optodes was examined, one in each year. The optode was part of an autonomous measurement system (FerryBox) on a ferry operating between Portsmouth (UK) and Bilbao (Spain). On crossings during which water samples were collected manually, the optode outputs were compared to measurements of dissolved oxygen made by Winkler titrations. The optodes maintained good stability with no evidence of instrumental drift during the course of a year. Over the observed concentration range (230–330 mM m⁻³) the optode data were approximately 2% low in both years. By fitting the optode data to the Winkler data the median difference between the optode and Winkler measurements is reduced to less than 1 mM m⁻³ (0.3%) in both years. The most appropriate calibration factor for 2005 was corrected O₂ = Optode O₂ × 1.018 and for 2006 the corresponding equation is corrected O₂ = Optode O₂ × 0.884 + 36.8. The standard deviation (95%) of the difference between the individual Winkler measurements was 5 mM m⁻³ and 3 mM m⁻³ in 2005 and 2006 respectively.Calculation of the oxygen saturation anomaly is required for calculation of the air sea exchange of oxygen and net biological production. This calculation requires the use of both salinity and temperature data. Salinity is measured to better than 0.1 so the corresponding error in anomaly is less than 0.2 mM m⁻³. Distortion of the temperature data is present due to warming of the water pumped to the optode. In winter this warming at the optode may be as great as 0.4 °C. The difference in the pumped water temperature can be corrected for by reference to other measurements of sea surface temperature reducing the error to less than 1 mM m⁻³.     

Effects of irradiance on benthic and water column processes in a Gulf of Mexico estuary: Pensacola Bay, Florida, USA

We examined the effect of light on water column and benthic fluxes in the Pensacola Bay estuary, a river-dominated system in the northeastern Gulf of Mexico. Measurements were made during the summers of 2003 and 2004 on 16 dates distributed along depth and salinity gradients. Dissolved oxygen fluxes were measured on replicate sediment and water column samples exposed to a gradient of photosynthetically active radiation. Sediment inorganic nutrient (NH₄⁺, NO₃⁻, PO₄³⁻) fluxes were measured. The response of dissolved oxygen fluxes to variation in light was fit to a photosynthesis–irradiance model and the parameter estimates were used to calculate daily integrated production in the water column and the benthos. The results suggest that shoal environments supported substantial benthic productivity, averaging 13.6 ± 4.7 mmol O₂ m⁻² d⁻¹, whereas channel environments supported low benthic productivity, averaging 0.5 ± 0.3 mmol O₂ m⁻² d⁻¹ (±SE). Estimates of baywide microphytobenthic productivity ranged from 8.1 to 16.5 mmol O₂ m⁻² d⁻¹, comprising about 16–32% of total system productivity. Benthic and water column dark respiration averaged 15.2 ± 3.2 and 33.6 ± 3.7 mmol O₂ m⁻² d⁻¹, respectively Inorganic nutrient fluxes were generally low compared to relevant estuarine literature values, and responded minimally to light exposure. Across all stations, nutrient fluxes from sediments to the water column averaged 1.11 ± 0.98 mmol m⁻² d⁻¹ for NH₄⁺, 0.58 ± 1.08 mmol m⁻² d⁻¹ for NO₃⁻, 0.01 ± 0.09 mmol m⁻² d⁻¹ for PO₄³⁻. The results of this study illustrate how light reaching the sediments is an important modulator of benthic nutrient and oxygen dynamics in shallow estuarine systems.     

Cultural sediment analyses and transitions in early fishing activity at Langenesværet,Vesterålen,Northern Norway

The development of specialized and commercial fishing activity in the island archipelago of Lofoten and Vesterålen in northern Norway is a critical foundation from which to understand the subsequent spread of commercial fishing across the north Atlantic region during the medieval and early modern period. One little understood aspect of this development is the relationship between medieval commercial fishing stations (fiskevaer) and earlier fishing activity. In this article, cultural sediment deposits at Langenesværet, Vesterålen, Northern Norway provide an opportunity to examine this relationship and its implications for current historical models of fishing development in northern Norway and the north Atlantic region. Conventional and AMS radiocarbon dating techniques are used to establish a chronology for the deposits, while activities associated with the sediments are characterized using thin‐section micromorphology supported by proton induced X‐ray emission spectrometry (PIXE). The results suggest that the site commenced formation as early as ca. 3000 B.C. and that the site was first used for specialized fishing activity from the early centuries A.D. The medieval commercial fiskevaer settlement at Langenesværet was introduced to an area that had a longstanding tradition of specialised fishing activity. © 2000 John Wiley & Sons, Inc.     

A Fissure-Controlled Acidic Volcanic Centre (Ordovician) at Yr Arddu,North Wales

The Yr Arddu Tuffs (Ordovician) are a sequence of predominantly welded acid ash-flow tuffs in the outlier centred on Yr Arddu (North Wales). The tuffs accumulated above a NNE-trending fracture, the Yr Arddu Fracture, which had previously influenced sedimentation. The heterogeneity of the tuffs and their restricted development suggest that they represent proximal accumulations from small or suppressed (boiling-over) eruption columns. The eruptions and emplacement developed, at least in the initial stages, in a submarine environment. Lithological, geochemical and palaeontological evidence indicates that the tuffs represent the earliest eruptive phase of the Lower Rhyolitic Tuff Formation. They were later intruded by comagmatic rhyolite domes, whose alignment reflects the continued influence of the early fracture.