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631.
The objective of this project was to empower people of Blyth Valley in Northumberland (northeast England) to contribute to the management of their coastal heritage. A group of volunteers, the Links Conservation Group, working in collaboration with the environmental managers (Blyth Valley Borough Council), scientists, local specialists and other volunteers, surveyed the biodiversity, social, cultural and industrial history and profiles of the dunes, as well as their perceived value to local residents. The Group used this information to develop management plans for the dunes. The recommendations have contributed to planning processes at three levels: (i) national coastal management plans; (ii) regional plans; and (iii) plans for further action at the local community level. 相似文献
632.
Paula K. Dunbar Kelly J. Stroker Vanita R. Brocko Jesse D. Varner Susan J. McLean Lisa A. Taylor Barry W. Eakins Kelly S. Carignan Robin R. Warnken 《Pure and Applied Geophysics》2008,165(11-12):2275-2291
In response to the 2004 Indian Ocean tsunami, the United States began a careful review and strengthening of its programs aimed at reducing the consequences of tsunamis. Several reports and calls to action were drafted, including the Tsunami Warning and Education Act (Public Law 109–424) signed into law by the President in December 2006. NOAA’s National Geophysical Data Center (NGDC) and co-located World Data Center for Geophysics and Marine Geology (WDC-GMG) maintain a national and international tsunami data archive that fulfills part of the P.L. 109-424. The NGDC/WDC-GMG long-term tsunami data archive has expanded from the original global historical event databases and damage photo collection, to include tsunami deposits, coastal water-level data, DART? buoy data, and high-resolution coastal DEMs. These data are used to validate models, provide guidance to warning centers, develop tsunami hazard assessments, and educate the public about the risks from tsunamis. In this paper we discuss current steps and future actions to be taken by NGDC/WDC-GMG to support tsunami hazard mitigation research, to ultimately help save lives and improve the resiliency of coastal communities. 相似文献
633.
A modified light transmission visualization method for DNAPL saturation measurements in 2-D models 总被引:1,自引:0,他引:1
In this research, a light transmission visualization (LTV) method was used to quantify dense non-aqueous phase liquids (DNAPL) saturation in two-dimensional (2-D), two fluid phase systems. The method is an expansion of earlier LTV methods and takes into account both absorption and refraction light theories. Based on this method, DNAPL and water saturations can rapidly be obtained point wise across sand-packed 2-D flow chambers without the need to develop a calibration curve. A single point calibration step is, however, needed when dyed DNAPL is used to account for the change in the transmission factor at the dyed DNAPL–water interface. The method was applied to measure, for the first time, undyed DNAPL saturation in small 2-D chambers. Known amounts of DNAPL, modeled by tetrachloroethylene (PCE), were added to the chamber and these amounts were compared to results obtained by this LTV method. Strong correlation existed between results obtained based on this method and the known PCE amounts with an R2 value of 0.993. Similar experiments conducted using dyed PCE showed a stronger correlation between results obtained by this LTV method and the known amounts of dyed PCE added to the chamber with an R2 value of 0.999. The method was also used to measure dyed PCE saturation in a large 2-D model following sparging experiments. Results obtained from image analyses following each sparging event were compared to results obtained by two independent techniques, namely gas chromatography–mass spectrometry (GC/MS) analyses and carbon column extraction. There was a good agreement between the results obtained by this LTV method and those obtained by the two independent techniques when experiments were carried out under stable light source conditions and errors in mass balance were minor. The method presented here can be expanded to measure fluid contents in three fluid phase systems and provide a non-destructive, non-intrusive tool to investigate changes in DNAPL architecture and flow characteristics in laboratory experiments. 相似文献
634.
635.
Leanne C. Cullen-Unsworth Lina Mtwana Nordlund Jessica Paddock Susan Baker Len J. McKenzie Richard K.F. Unsworth 《Marine pollution bulletin》2014
Seagrass ecosystems are diminishing worldwide and repeated studies confirm a lack of appreciation for the value of these systems. In order to highlight their value we provide the first discussion of seagrass meadows as a coupled social–ecological system on a global scale. We consider the impact of a declining resource on people, including those for whom seagrass meadows are utilised for income generation and a source of food security through fisheries support. Case studies from across the globe are used to demonstrate the intricate relationship between seagrass meadows and people that highlight the multi-functional role of seagrasses in human wellbeing. While each case underscores unique issues, these examples simultaneously reveal social–ecological coupling that transcends cultural and geographical boundaries. We conclude that understanding seagrass meadows as a coupled social–ecological system is crucial in carving pathways for social and ecological resilience in light of current patterns of local to global environmental change. 相似文献
636.
Regional effects of climate change on reindeer: a case study of the Muotkatunturi region in Finnish Lapland 总被引:2,自引:0,他引:2
Susan E. Lee Malcolm C. Press John A. Lee Tim Ingold Terhi Kurttila 《Polar research》2000,19(1):99-105
Few studies have investigated current climate changes for high latitude regions, and the impact of such changes on reindeer and indigenous people. Previous work by other authors has identified snow and ice conditions in winter as being critical in determining the availability of forage for reindeer. Deep snow makes it difficult to access food. Lack of food weakens the herd and can reduce the allocation of nutrients to the development of the foetus in the female deer. Climate data for Lapland, northern Finland, and Karasjok, northern Norway, are examined, together with reindeer calf numbers for the period 1977 to 1994 for the Muotkatunturi region (68°N 25°30'E). Between 1883 and 1993, precipitation increased but temperatures showed no clear warming or cooling trend. However, since the late 1980s, temperatures have increased. A regression analysis on the climate and reindeer data found that the warmer the winter prior to the rut, the fewer the live calves recorded the following year (r = 0.529, p < 0.05). Also, the wetter the winter prior to the rut, the fewer the calves recorded (r = 0.427, p < 0.10). In contrast, the warmer the autumn prior to their birth, the greater the number of calves recorded (r = 0.474, p < 0.10). These results suggest that as climate changes and winters become warmer and wetter with increased snowfall, calf numbers will decline. These findings have important implications for the Saami people who are heavily dependent on the reindeer for their livelihood. 相似文献
637.
Costanza Morino Susan J. Conway Matthew R. Balme John Hillier Colm Jordan Þorsteinn Sæmundsson Tom Argles 《地球表面变化过程与地形》2019,44(1):144-159
Debris flows are fast-moving gravity flows of poorly sorted rock and soil, mixed and saturated with water. Debris-flow initiation has been studied using empirical and experimental modelling, but the geomorphic changes, indicative of different triggering processes, are difficult to constrain with field observations only. We identify signatures to distinguish two different debris-flow release styles by integrating high-resolution multi-temporal remote sensing datasets and morphometric analysis. We analyse debris flows sourced above the town of Ísafjörður (Iceland). Two debris-flow triggering processes were previously hypothesised for this site: (i) slope failure, characterised by landslides evolving into debris flows; and (ii) the fire-hose effect, in which debris accumulated in pre-existing, steep-sided bedrock passages is transported by a surge of water. It is unknown which process dominates and determines the local risk. To investigate this question, we compare airborne LiDAR elevation models and aerial photographs collected in 2007 with similar data from 2013. We find that two new debris-flow tracks were created by slope failures. These are characterised by steep sliding surfaces and lateral leveed channels. Slope failure also occurred in two large, recently active tracks, creating the preparatory conditions for the fire-hose effect to mobilise existing debris. These tracks show alternating zones of fill and scour along their length, and debris stored below the source-area at rest angles >35°. Our approach allows us to identify and quantify the morphological changes produced by slope failure release process, which generated the preparatory conditions for the fire-hose effect. As debris flows are rarely observed in action and morphological changes induced by them are difficult to detect and monitor, the same approach could be applied to other landscapes to understand debris-flow initiation in the absence of other monitoring information, and can improve the identification of zones at risk in inhabited areas near hillslopes with potential for debris flows. © 2018 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd. 相似文献
638.
The presence of artificial sweeteners in environmental samples is increasingly used to detect wastewater (and recently landfill leachate) in rivers, lakes and groundwater. Through routine laboratory quality assurance/quality control procedures, it was discovered that some syringe‐tip filters leach saccharin when used to process water samples. We subsequently tested several brands of filters to determine if they leached any of the four common artificial sweeteners analyzed in environmental samples, acesulfame, saccharin, cyclamate, and sucralose. Of the six types of filters tested, only one brand was a source of artificial sweeteners and the only artificial sweetener found was saccharin. The source of the saccharin in the filters is unknown but it is likely the result of some step in the manufacturing process. The saccharin was typically removed from these filters using a distilled water rinse of 13 mL or less. As a precaution, filters should be pre‐tested for the presence of saccharin and/or filters should be flushed with distilled water or sample prior to the collection of water samples for artificial sweetener analyses. 相似文献
639.
Miriam J. Doyle Susan J. Picquelle Kathryn L. Mier Michael C. Spillane Nicholas A. Bond 《Progress in Oceanography》2009,80(3-4):163-187
The present study investigates ecological patterns and relationships to environmental variables among a time-series of larval fish species abundance from late spring surveys (1981–2003) in the northwest Gulf of Alaska (GOA). Links between interannual variation in species abundance and the physical environment were explored using generalized additive modeling (GAM). Trends in larval abundance and connections with physical variables displayed patterns that indicate unique and complex responses among species to environmental forcing during the larval period. In particular, the observed patterns suggest that ontogenetic-specific responses, representing sub-intervals of early life, are important. In addition, a notable degree of synchrony in larval abundance trends, and similarity in links with physical variables, were observed among species with common early life history patterns. The deepwater spawners, northern lampfish, arrowtooth flounder, and Pacific halibut, were most abundant in the study area during the 1990s, in association with enhanced wind-driven onshore and alongshore transport. Years of high abundance for Pacific cod, walleye pollock, and northern rock sole were associated with cooler winters and enhanced alongshore winds during spring. High larval abundance for spring–summer spawning rockfish species and southern rock sole seemed to be favored by warmer spring temperatures later in the time-series. This apparent exposure–response coupling seems to be connected to both local-scale and basin-scale environmental signals, to varying degrees depending on specific early life history characteristics. Understanding such ecological connections contributes to the evaluation of vulnerability and resilience among GOA species’ early life history patterns to fluctuating climate and oceanographic conditions. This investigation also provides crucial information for the identification of “environmental indicators” that may have a broad-spectrum effect on multiple species early life history stages, as well as those that may be more species-specific in exerting control on early life history survival. Of particular interest was the emergence of the EP–NP (East Pacific–North Pacific) teleconnection index as the top-ranked variable in the GAM models exploring the connections between late spring larval abundance and the physical environment. The EP–NP index represents an important and often primary mode of spring–summer atmospheric variability in the northeast Pacific, with a strong expression in the GOA, and its connection with species in this study implies that it may be a climate mode of significant ecological importance. 相似文献
640.
Mark S. Fonseca W. Judson Kenworthy Emily Griffith Margaret O. Hall Mark Finkbeiner Susan S. Bell 《Estuarine, Coastal and Shelf Science》2008
The scale of landscape pattern formation of an ecological community may provide clues as to the processes influencing its spatial and temporal dynamics. We conducted an examination of the spatial organization of an annual seagrass (Halophila decipiens) in an open ocean setting at two spatial scales and growing seasons to identify the relative influence of external (hurricanes) versus internal (clonal growth) factors. Visual surveys of seagrass cover were conducted over 2 years within three replicate 1 km2 study areas each separated by ∼25 km in an inshore–offshore transect along the southwest coast of Florida at depths between ∼10 and 30 m. A towed video sled allowed observations of seagrass cover of 1 m2 areas approximately every 6 m over thousands of meters of evenly spaced transects within the study areas (coarse scale). The towed video revealed that 17.5% of the seafloor was disturbed irrespective of location or sample time. Randomly selected 10 × 10 m quadrats within the larger, 1 km2 study areas were completely surveyed for seagrass cover by divers at 0.625 m2 resolution (fine scale). The coarse-scale observations were tested using both conventional geostatistics and an application of a time-series technique (Runs test) for scale of seagrass cover contiguity. Fine-scale observations were examined using conventional geostatistics and a least squares approach (cumulative logistic). 相似文献