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71.
Helena Pimlott-Wilson 《Geoforum》2012,43(5):916-925
This paper seeks to further understanding about children’s experiences and knowledges of home and employment reconciliation. The paper, which draws on empirical research with children living in socio-economically diverse areas of North West England, makes three contributions. Firstly, it argues that children must be included in studies of work-balance, as the strategies parents adopt affect the way children are socialised towards appropriate divisions of domestic, caring and labour force responsibilities. Secondly, it contributes to research which considers the temporal and spatial boundaries between home and paid work to add the verbal dimension; demonstrating that children have varying levels of conversational interaction with their parents about employment in the home sphere. Finally, the paper contends that these distinct approaches to the verbal and spatial boundaries of production and reproduction are influenced by class dispositions, localised parenting cultures and constructions of childhood. This results in some children being shielded from the realities of paid work, whilst others are socialised to cope with labour market instability. 相似文献
72.
Non-Governmental Organizations (NGOs) are playing important roles in environmental conservation and management. Some are actively involved in the development and implementation of marine spatial planning (MSP), especially in Europe where this has been embodied within a European Directive. MSP is being used by many countries to sustainably manage coastal and marine areas, and reduce conflicts. However, recommendations regarding specific NGO roles within the MSP process are lacking. Consequently, to fill this gap and discuss a way forward, a session at the 5th Global Conference on Oceans, Coasts and Islands (GOF5) brought together MSP experts and NGO representatives. This paper reports the conclusions of these discussions and presents a summary guideline document for efficient and effective NGO MSP engagement. 相似文献
73.
Mary E. Wright Helena M. Solo-Gabriele Samir Elmir Lora E. Fleming 《Marine pollution bulletin》2009,58(11):1649-1656
The goal of this study was to quantify the microbial load (enterococci) contributed by the different animals that frequent a beach site. The highest enterococci concentrations were observed in dog feces with average levels of 3.9 × 107 CFU/g; the next highest enterococci levels were observed in birds averaging 3.3 × 105 CFU/g. The lowest measured levels of enterococci were observed in material collected from shrimp fecal mounds (2.0 CFU/g). A comparison of the microbial loads showed that 1 dog fecal event was equivalent to 6940 bird fecal events or 3.2 × 108 shrimp fecal mounds. Comparing animal contributions to previously published numbers for human bather shedding indicates that one adult human swimmer contributes approximately the same microbial load as one bird fecal event. Given the abundance of animals observed on the beach, this study suggests that dogs are the largest contributing animal source of enterococci to the beach site. 相似文献
74.
Cristina Ortega Helena M. Solo-Gabriele Amir Abdelzaher Mary Wright Yang Deng Lillian M. Stark 《Marine pollution bulletin》2009,58(9):1374-1381
The objective of this study was to evaluate whether indicator microbes and physical–chemical parameters were correlated with pathogens within a tidally influenced Estuary. Measurements included the analysis of physical–chemical parameters (pH, salinity, temperature, and turbidity), measurements of bacterial indicators (enterococci, fecal coliform, Escherichia coli, and total coliform), viral indicators (somatic and MS2 coliphage), viral pathogens (enterovirus by culture), and protozoan pathogens (Cryptosporidium and Giardia). All pathogen results were negative with the exception of one sample which tested positive for culturable reovirus (8.5 MPN/100 L). Notable physical–chemical parameters for this sample included low salinity (<1 ppt) and high water temperature (31 °C). Indicator bacteria and indicator virus levels for this sample were within average values typically measured within the study site and were low in comparison with levels observed in other freshwater environments. Overall results suggest that high levels of bacterial and viral indicators were associated with low salinity sites. 相似文献
75.
Sediment depth and habitat as predictors of the diversity and composition of sediment bacterial communities in an inter‐tidal estuarine environment 下载免费PDF全文
Daniel F. R. Cleary Francisco J. R. C. Coelho Vanessa Oliveira Newton C. M. Gomes Ana R. M. Polónia 《Marine Ecology》2017,38(2)
Saltmarshes, seagrass meadows and mudflats are key habitats in estuarine ecosystems. Despite being involved in key ecological processes, the influence of different estuarine habitats on sediment bacterial communities remains understudied. Few studies have analysed and compared the bacterial communities of more than one estuarine habitat at different depths. Here, we investigated to what extent different habitats (mudflats; mono‐specific plots of seagrass [Zostera noltei] and two saltmarsh plants [Juncus maritimus and Spartina maritima]) and sampling depth (0, 5, 10 cm) influence variation in sediment bacterial composition. Our results showed significant differences in the abundance of selected higher taxa amongst habitats and depths. Surface sediment was characterized by bacteria assigned to the Acidimicrobiia, Flavobacteriia, Thiotrichales, Alteromonadales and Rhodobacterales, whereas in deeper sediment Deltaproteobacteria and Anaerolineae were dominant. Juncus sediment, in turn, presented the most distinct bacterial community, with Myxococcales abundant in this habitat. Sampling depth and habitat proved significant predictors of variation in sediment bacterial composition. The compositional dissimilarities amongst habitats and depths suggest functional divergence and complementarity, thus enhancing ecosystem functioning and health. Given the compositionally distinct communities found in different habitats and depths, our study corroborates the importance of conserving a diverse array of estuarine habitats. 相似文献
76.
J.P. Coelho H. Santos J. Falcão M.E. Pereira M.A. Pardal 《Marine pollution bulletin》2010,60(8):1372-1375
The annual and life-cycle mercury bioaccumulation pattern in selected tissues of the economically relevant Elasmobranchii species Scyliorhinus canicula was studied, and the risks associated with its consumption evaluated.Preferential mercury bioaccumulation occurred in muscle tissue, and followed the order muscle > heart > liver > gills > pancreas. Total mercury in muscle tissue ranged from 0.13 mg kg−1 (wwt) in 1+ year old males to 0.8 mg kg−1 (wwt) in 8+ year old mature females, with no significant differences found between genders, and no clear lifespan bioaccumulation pattern observed, except for mature females. Organic mercury in the muscle ranged from 0.05 mg kg−1 (wwt) to 0.52 mg kg−1 (wwt), corresponding to an average of 70% of total mercury content. In mature females, a significant correlation (R = 0.99, P = 0.01) was found between size and organic mercury fraction, suggesting reproduction as an important factor controlling organic mercury bioaccumulation in the spotted dogfish. 相似文献
77.
Bank erosion of legacy sediment at the transition from vertical to lateral stream incision 下载免费PDF全文
Nathan J. Lyons Michael J. Starek Karl W. Wegmann Helena Mitasova 《地球表面变化过程与地形》2015,40(13):1764-1778
Streambank erosion is a primary source of suspended sediments in many waterways of the US Atlantic Piedmont. This problem is exacerbated where banks are comprised of fine sediment produced by the intensive land use practices of early European settlers. A stream in this region, Richland Creek incises into banks comprised of three stratigraphic layers associated with historic land use: pre‐European settlement, early European agriculture and development, and water‐powered milldam operation. This study aims to identify the bank processes along a reach of Richland Creek that is eroding towards its pre‐disturbance elevation. The volume of material that has eroded along this stream since the milldam breached was calculated by differencing a reconstructed surface of the pond bed and an aerial lidar digital terrain model (DTM). Immediately downstream from the study reach, the channel is floored by bedrock and immediately upstream the rate of channel erosion approximately doubled along the longitudinal profile of Richland Creek, which indicate that the study reach spans the transition from a channel dominated by vertical incision in the upstream direction to horizontal widening in the downstream direction. The combined hydrometeorological conditions and dominant processes causing reach‐scale cut bank erosion were investigated with analyses of stream stage, precipitation, and streambank volumetric and surfaces change that was measured during nine terrestrial lidar surveys in 2010–2012. The spatial variability of erosion during a simulated precipitation event was examined in a field‐based experiment. Erosion was greatest where mill pond sediment columns detached along vertical desiccation and horizontal seepage cracks. This sediment accumulated on the bank toe throughout the study and was a source of readily‐entrained fine sediment contrary to the upper reaches where depositional accommodation space is more limited. Findings suggest that hotspots of sediment excavation progress upstream, indicating that restoration efforts should focus upon stabilizing banks at these locations. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
78.
Michel Michaelovitch de Mahiques Ilana Klein Coaracy Wainer Leticia Burone Renata Nagai Silvia Helena de Mello e Sousa Rubens Cesar Lopes Figueira Ilson Carlos Almeida da Silveira Mrcia Caruso Bícego Daniel Pavani Vicente Alves
yvind Hammer 《Quaternary International》2009,206(1-2):52
A high-resolution, multi-proxy record has been used to determine the environmental changes during the Holocene on the southern Brazilian shelf. Present oceanographic conditions reveal wind and freshwater input as the determinants of short-term productivity changes in the study area. Magnetic susceptibility and grain-size variations, together with proxies of productivity (organic carbon, carbon accumulation rate, Ba, Sr, and Ca content, Ba/Al, Ba/Ti, and Al/Ti ratios) were analyzed and compared with proxies of redox condition (V/Ti ratio), terrigenous input (Fe/Ca and Ti/Ca ratios), as well as other Element/Ti ratios, to evaluate the paleoceanographic and paleoclimatic changes over the period.The core covers a time interval of about 7650 years, with sedimentation rates varying from 0.025 to 0.250 cm a−1, which represent time intervals of between 8 and 80 a per sample. There is a clear change in the sedimentation rate at about 2800 B.P.All grain-size and elemental results indicate the occurrence of conspicuous changes between 5200 and 5000 cal. B.P., as well as between 3000 and 2800 cal. B.P. A comparison of the results with the palynological information available from the adjacent continental areas suggests that the sedimentary changes in this last interval may be correlated with the onset of modern climatic conditions in South America, and especially, with the onset of the Plata Plume Water, a water mass that carries cold, less saline waters towards the north. However, minor changes are observed at ca. 1500 B.P. and are correlated with an increase in the atmospheric humidity. Furthermore, a time-series analysis undertaken using several proxies indicated the occurrence of Sub-Milankovitch cycles, which may be compared with those reported worldwide. 相似文献
79.
Carlos J. Archanjo Patrick Launeau Maria Helena B. M. Hollanda José Wilson P. Macedo Dunyi Liu 《International Journal of Earth Sciences》2009,98(8):1793-1807
Anisotropy of magnetic susceptibility (AMS) applied to an alkaline granite from Meruoca (NE Brazil) recorded weak anisotropies,
typically below 4%, and a considerable dispersion of the AMS axes. Red-clouded feldspars and clots of metasomatic minerals
enclosed in magmatic crystals indicate that hydrothermal fluids altered the granite. U–Pb isotopic data show high-common Pb
on zircons but allowed the calculation of a mean SHRIMP age of 523 ± 9 Ma attributed to the magmatic crystallization. Growth
of fine oxides by late fluid–rock interactions was responsible for the scattering of AMS. Rock magnetic data indicate they
consist mainly of an oxidized magnetite and (titano)hematite. Shape preferred orientation of mafic aggregates measured in
granite quarries shows that the pluton preserves a gently dipping magmatic foliation. AMS in some quarries with a well-defined
magmatic fabric, however, remains highly dispersed. When AMS mimics the mafic shape fabric, only magnetic foliations share
a common orientation. Locally, AMS grounded in coarse Ti-poor magnetite associated with titanite develops a consistent subhorizontal
oblate fabric that agrees with tectonic models suggesting that the cupola of the pluton has been exposed by erosion. 相似文献
80.
Wesley R. Farnsworth Ólafur Ingólfsson Riko Noormets Lis Allaart Helena Alexanderson Mona Henriksen Anders Schomacker 《Boreas: An International Journal of Quaternary Research》2017,46(3):585-603
Evidence of a dynamic Holocene glacial history is preserved in the terrestrial and marine archives of St. Jonsfjorden, a small fjord‐system on the west coast of Spitsbergen, Svalbard. High‐resolution, remotely sensed imagery from marine and terrestrial environments was used to construct geomorphological maps that highlight an intricate glacial history of the entire fjord‐system. The geomorphology and stratigraphy indicate an early Holocene local glacier advance constrained to the Lateglacial–early Holocene transition. Identification and 14C dating of the thermophilous bivalve mollusc Modiolus modiolus to 10.0±0.12 cal. ka BP suggest a rapid northward migration of the species shortly after deglaciation. Further evidence enhances the understanding of the onset and subsequent climax of the Neoglacial‐Little Ice Age in inner St. Jonsfjorden. The present‐day terminus of Osbornebreen, the dominating glacier system in St. Jonsfjorden, is located over 8.5 km up‐fjord from its Neoglacial maximum extent. Cross‐cutting relationships suggest subsequent advances of all the smaller glaciers in the area following the break‐up of Osbornebreen. Glacial deposits, landforms and their cross‐cutting relationships observed in both terrestrial and marine settings imply a complex and highly dynamic environment through the later part of the Holocene. 相似文献