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1.
Several species of sandy beach invertebrates regularly switch between burial in the sand during the day and surface activity
at night to feed on stranded organic matter. Because all species consume essentially the same type of food (i.e., wrack) deposited
over a restricted area, the potential for competition exists. Conversely, spatial and temporal segregation of surface activity
behaviour is predicted to allow for niche separation. Here, we tested whether such behavioural niche separation occurs in
three species of sympatric crustaceans (the talitrid amphipods Talitrus saltator (Montagu 1808) and Talorchestia brito Stebbing 1891, and the oniscoidean isopod Tylos europaeus Arcangeli 1938). We also assessed whether surface activity is modulated by weather, sea conditions and moon phases. Surface
activity was measured over three consecutive moon phases on an exposed beach on the Atlantic Coast of Spain using pitfall
traps along three transects from the foredunes to the swash. Adults of the amphipod T. saltator and the isopod T. europaeus overlapped spatially and temporally in their surface activity for most of the night. By contrast, the activity of T. brito was strongly disjunct in time and concentrated into significantly shorter bouts around dawn or dusk. Niche differentiation
was also evident along the space axis, where T. brito occurred distinctly lower on the beach. Although several environmental factors (e.g., air and sand temperature, humidity,
atmospheric pressure, wind speed and wind direction) were correlated with surface activity, this was highly variable amongst
species, life stages, and synodic phases, and did not obscure the fundamental mosaic of spatio-temporal heterogeneity amongst
species. Nocturnal feeding on beach wrack creates the potential for competition amongst sympatric crustaceans which can, however,
be mitigated by behaviour patterns that separate consumers in time and space. 相似文献
2.
G. Anfuso J. A. Martínez del Pozo F. J. Gracia F. López-Aguayo 《Journal of Coastal Conservation》2003,9(1):49-56
We present a morphodynamic study of an apparently homogeneous rectilinear coast in SW Spain. The study area covers 14 km of
mesotidal sandy beaches, interrupted in some places by rocky-shore platforms. The method used consisted of a monthly monitoring
of 12 beach profiles during two years. According to the results obtained from the study, which also include granulometric
analyses andin situ determination of the beach disturbance depth, three main beach classes have been differentiated: low-reflective beaches,
dissipative beaches and rocky-shore platform beaches. Their longitudinal distribution is not linked to their distance to the
main source of sediments in the area (mouth of the river Guadalquivir). Instead, a very irregular long-shore variation of
morphodynamic beach states appears. It is deduced that this long-shore variation is mainly linked to local contouring conditions
(e.g. the presence of rocky shoals which affect wave-breaking processes), and not to the regional long-shore currents prevailing
in the zone. 相似文献
3.
Carmen M. Rosskopf Gianluigi Di Paola David E. Atkinson Germán Rodríguez Ian J. Walker 《Journal of Coastal Conservation》2018,22(5):879-895
A study on the modern dynamics and shoreline changes from 1954 to 2014 of the Molise coast (central Adriatic Sea) has been carried out. Short to long-term shoreline changes and associated surface area variations have been assessed in GIS environment for the study coast, subdivided in nine coastal segments (S1-S9), by using 100-m regularly spaced transects. In addition, the possible influence of natural and anthropogenic factors, especially of climatic variability and engineered shoreline defense structures, has been investigated. The Molise coast has experienced notable long-term erosion (period 1054-2014) that caused an overall coastal land loss of approximately 940,000 m2. Erosion was, yet, limited to coastal segments S1 and S7, nearest to the mouths of major rivers, namely Trigno and Biferno, while the major part of the study coast has remained essentially stable or even advanced. Increased shoreline protection by defense structures has generally favoured shoreline stability and frequently generated shoreline advance, except for segments S1 and S7. Observed differences in shoreline change rates over time at the decadal to interannual scale, have not find a response in the analysis of available data on meteo-marine conditions of the Molise coast and climate variability indices, pointing out the need to improve knowledge on meteomarine conditions and on climatic variability forcing of the study area. From 2004 to 2014, the Molise shoreline remained essentially stable. Nonetheless, most recent shoreline changes (period 2011-2014) and modern shoreline dynamics indicate that erosion has become more widespread, involving at least part of segments S2-S3 and S8-S9, located south of the river mouth segments. The localized long-term shoreline retreat and most recent shoreline erosion appear to be primarily related to channel adjustments of the Biferno and Trigno rivers that occurred since the 1950s under the control of human interventions on the rivers, especially the construction respectively of a dam and a check dam along their lower courses, that trap of most of their solid load, affecting so adversely the sediment budget of the river mouths areas and adjacent beaches. Overall data acquired on the recent shoreline evolution and modern shoreline dynamics of the Molise coast and on related causal factors provide a good basic knowledge for regional coastal management purposes, and for further scientific purposes. Particularly, they suggest the opportunity to deepen a number of aspects such as the relationship between the coast and river catchments feeding it, the possible influences on the Molise shoreline dynamics of the neighbouring coasts, the efficiency/obsolescence of defense structures and the present-day vulnerability to coastal erosion of the Molise coast. 相似文献
4.
70 beaches in Wales, UK, were investigated with regard to the quality of beach scenery using video panoramas. Beaches were
given a score from zero to 20 by a panel of 24 coastal managers (National Park and Heritage Coast Wardens, etc.) and 42 final
year Degree or Master of Science students specializing in environmental sciences. Mean scores of coastal managers ranged from
16.1 (Broadhaven, S. Pembrokeshire; 80%) to 3.8 (Prestatyn, North Wales; 19%), while scores of students ranged from 16.0 (Barafundle,
S. Pembrokeshire; 80%) to 6.1 (Trecco Bay, Porthcawl; 31%). Wave height, number of people present on the beach and position
on the final videotape did not have significant effects on mean scores generated by either group. With both groups a strong
preference was observed for undeveloped beaches over those where anthropogenic structures were prominent (p=0.00), but beach commercialization level had an independent effect only on scores from the student group (p=0.02). Cloud cover at time of filming had a significant effect (p=0.00) on scoring, so a correction was applied for final score calculation and ranking. The findings contribute to management
of coastal aesthetic resources by providing a quantitative evaluation scheme. It is proposed to use these scores for beach
scenery/aesthetic quality in a novel, comprehensive beach rating system. 相似文献
5.
One of the main goals in decision-making for sustainable development is to identify and choose the most sustainable option among different alternatives. This process usually involves a large number of stakeholders with multiple, often conflicting objectives. Facilitating and resolving such difficult decision situations can be complex, so that a more formal and systematic approach to decision-making may be necessary. This paper proposes an integrated multiple criteria decision-support framework specifically developed to provide a systematic, step-by-step guidance to decision-makers. The framework, which is suitable for both corporate and public policy-making in the context of sustainable development, comprises three steps: problem structuring, problem analysis and problem resolution. This paper concentrates on problem analysis and resolution, where decision-makers articulate their preferences for different decision criteria. A suitable Multiple Criteria Decision Analysis (MCDA) technique, such as multi-objective optimisation, goal programming, value-based and outranking approaches, is then used to model the preferences. These techniques are discussed here in some detail, to provide guidance on the choice of the most appropriate MCDA method. Based on the outcome of preference modelling, which estimates the overall 'value' of each alternative being considered, decision-makers can then choose the 'best' or most sustainable option. Such an integrated decision-support framework is useful for providing structure to the debate, ensuring dialogue among decision-makers and showing trade-offs between conflicting objectives. In this way, it may be possible to create shared understanding about the issues, generate a sense of common purpose and, often, resolve 'difficult' decision problems. 相似文献
6.
Macroplastics are well known to be highly hazardous for marine wildlife, as well as being the most frequently encountered type of marine litter. The main objective of this work was to address the impact of beach kiosk presence on the occurrence of marine debris in a highly frequented beach in Southeast Brazil. For this work, three areas close to kiosks and three areas distant from kiosks were chosen for sampling and comparison. We conducted three transects at each location, each one including two meters of vegetation, from which debris was collected. Samples were taken to the laboratory so that they could be weighed and the debris was classified according to material. Our results show that, in every scenario, plastic was the most frequently found material. In addition, the amount of paper was found to be higher in areas close to kiosks. Presence of kiosks does not have an overall direct impact on the amount of litter. However, we found vegetated areas to have significantly higher volumes of debris, both in areas with and without beach kiosks. 相似文献
7.
The composition of the diet of Citharus linguatula (L.) off the coast of the Gulf of Valencia, Spain, was determined between October 1989 and October 1990. The percentage of empty stomachs remained constant throughout the year, except for the period August to September, when a maximum was recorded coinciding with the reproductive period. Crustaceans (Mysidacea and Decapoda) and teleosts constituted the main prey. The composition of the prey ingested varied with predator size; small specimens contained a greater number of mysids in their stomachs, while decapods and fishes were more abundant in the stomachs of larger specimens. Diets varied seasonally: mysids were more important during autumn, whereas decapods were more important during winter and spring. Fishes were numerically most important in the diet in summer, but the frequency of occurrence was constant throughout the year. 相似文献
8.
John Munthe Eva Brorström-Lundén Magnus Rahmberg Leo Posthuma Rolf Altenburger Werner Brack Dirk Bunke Guy Engelen Bernd Manfred Gawlik Jos van Gils David López Herráez Tomas Rydberg Jaroslav Slobodnik Annemarie van Wezel 《Environmental Sciences Europe》2017,29(1):13
Background
This paper describes a conceptual framework for solutions-focused management of chemical contaminants built on novel and systematic approaches for identifying, quantifying and reducing risks of these substances.Methods
The conceptual framework was developed in interaction with stakeholders representing relevant authorities and organisations responsible for managing environmental quality of water bodies. Stakeholder needs were compiled via a survey and dialogue. The content of the conceptual framework was thereafter developed with inputs from relevant scientific disciplines.Results
The conceptual framework consists of four access points: Chemicals, Environment, Abatement and Society, representing different aspects and approaches to engaging in the issue of chemical contamination of surface waters. It widens the scope for assessment and management of chemicals in comparison to a traditional (mostly) perchemical risk assessment approaches by including abatement- and societal approaches as optional solutions. The solution-focused approach implies an identification of abatement- and policy options upfront in the risk assessment process. The conceptual framework was designed for use in current and future chemical pollution assessments for the aquatic environment, including the specific challenges encountered in prioritising individual chemicals and mixtures, and is applicable for the development of approaches for safe chemical management in a broader sense. The four access points of the conceptual framework are interlinked by four key topics representing the main scientific challenges that need to be addressed, i.e.: identifying and prioritising hazardous chemicals at different scales; selecting relevant and efficient abatement options; providing regulatory support for chemicals management; predicting and prioritising future chemical risks. The conceptual framework aligns current challenges in the safe production and use of chemicals. The current state of knowledge and implementation of these challenges is described.Conclusions
The use of the conceptual framework, and addressing the challenges, is intended to support: (1) forwarding sustainable use of chemicals, (2) identification of pollutants of priority concern for cost-effective management, (3) the selection of optimal abatement options and (4) the development and use of optimised legal and policy instruments.9.
ABSTRACTThe leather-processing industry (LPI) is constantly polluting the environment in Bangladesh. As a result, stakeholders are continuously pressurizing managers working in LPI to embrace green leather-processing activities. Thus, the green concept is attracting significant attention from managers in the Bangladeshi LPI. However, the industry is struggling with many barriers to implementing green supply chain management (GSCM). There are many studies regarding barriers to GSCM. However, those studies failed to show the possible pathways to implement GSCM. This study addresses the gap by evaluating barriers to GSCM considering effective pathways to GSCM. In this study, the Analytical Hierarchy Process (AHP) is integrated with Elimination Et Choix Traduisant La Realite (ELECTRE-I) method to identify and prioritize the barriers and to rank the possible pathways to implementing GSCM in the leather industry. To accredit the proposed framework, it is implemented on a leather-processing factory in Bangladesh. A sensitivity analysis is performed to inspect the strength of the outcome of this method. The outcome of this study indicates that the high cost of advanced technology is the most important barrier to implement GSCM while green technology and techniques are the most effective pathways to GSCM. The findings of this research will support researchers and practitioners by giving insights on barriers and possible pathways to implementing GSCM. 相似文献
10.
Incentive approaches are believed to be indispensable for effective conservation and successful management in protected areas. However, the actual effectiveness of these approaches is still debatable. We carried out a case study in Wolong Biosphere Reserve (WBR), the largest reserve for the giant panda (Ailuropoda melanoleuca), to evaluate the effectiveness of incentives. We obtained data from government documents and statistics, interviews and surveys on the employment status of public sector and industries. Results indicated that government-paid community-based conservation projects provided the most widespread and direct economic incentives. The conservation sector and several industries including hotels, hydropower and tourism have directly raised the employment level of local communities. The hotel industry, driven by the development of tourism, has been the most effective means of increasing local employment. However, the problem of immigrants attracted by the improved economic situation in WBR should be considered in the management plans. Suggestions for WBR management include development of quality ecotourism, vocational education for local young adults and new policies encouraging employment of local labour, both in the reserve and outside. Lessons learned from this research are constructive for the management of other protected areas. 相似文献
11.
ABSTRACTThe main purpose of Green Supply Chain Management (GSCM) is to improve the quality of supply chain management strategies and environmental performance. As per current statistics, the chemical industry is growing fast in Bangladesh. In order to compete for global competition, GSCM is essential in this sector. This paper proposes a systematic approach of structural framework whose aim is to enhance the probability of constructive implementation of GSCM in the field chemical industry in Bangladesh. Therefore, this framework evaluates the appropriate interrelationship along with the drivers of GSCM in the chemical industry. In total, eight drivers were finalized from an associated literature review with the help of survey and by taking expert opinions via the Delphi methodology. In addition to MICMAC analysis, the driving and the dependence powers for all the drivers were determined. Moreover, the structural frameworks for the drivers were developed by means of total interpretive structural modeling (TISM) technique. As a result, the findings indicate that the most significant driver was supplier pressure and willingness and the most important barrier was high cost. Finally, the main objective of this research is expected to help industrial managers to evaluate and understand the critical areas where they should emphasize to implement GSCM in the chemical industry. 相似文献
12.
Physical and biological gradients in a submarine cave on the Western Mediterranean coast (north-east Spain) 总被引:1,自引:0,他引:1
Submarine caves are semi-closed subsystems within the marine littoral ecosystem. One of the most striking features is the progressive reduction of the number of phyla, species, and biomass towards the interior of such a cave. The decrease in biomass has been explained as the result of low exchange rates of the water inside the caves which limit the supply of oxygen and food particles from the exterior. Many authors have proposed that this reduced exchange rate is associated with the occurrence of marked gradients in temperature, salinity, oxygen and light. Measurement of faunal abundance of a cave in the littoral zone of the Medes Islands (Catalonia, north-east Spain) made between June 1983 and July 1984, revealed a zonation similar to that in other Mediterranean caves. Animal biomass decreased from 260 g ash-free dry weight m-2 at the entrance to 80 g ash-free dry weight m-2 at the end of the cave (50 m from the mouth). A special technique for remote water-sampling was developed to avoid problems due to turbulence caused by divers in this semi-closed system. This involved the installation of a series of plastic tubes at different points along the axis of the cave. The water was brought to the surface using a battery-powered electric pump. The reliability of this method was verified by comparing the results with samples collected directly by divers. Sampling both in winter and summer showed no longitudinal gradients for temperature, salinity, oxygen, chlorophylla and the number and volume of suspended particles. These results suggest that there is a constant circulation within the cave which guarantees water-exchange. The decrease in biomass cannot be explained by physico-chemical gradients due to insufficient exchange with the external system. On a finer scale, however, along the walls of the cave there may exist boundary layers that are not affected by the general circulation. This could account for the observed decrease in the biomass of benthic organisms. 相似文献
13.
J. M. Gorostiaga 《Marine Biology》1994,120(2):311-322
Several aspects of the growth of the agarophyte Gelidium sesquipedale Clemente (Thuret) were studied in sublittoral populations of the Basque coast (northern Spain) from 1981 to 1986. The standing stock of the populations varied greatly with season. During two consecutive years, 60 to 70% of summer biomass had been lost by the end of the unfavourable period of year to growth (autumn and winter). The decline in biomass was mainly due to partial losses of branches, with more branches being lost from larger fronds. Yearly variations in the standing stock were also recorded. Production estimates obtained by a destructive sampling method were not satisfactory because of the spatial heterogeneity of the populations at the three locations studied. Indirect estimation of production by measuring the growth of marked fronds in a control quadrat gave more reliable estimates. Production values of 622±124, 735±147 and 615±123 g dry wt m-2 yr-1 were obtained at the three locations, respectively. Frond elongation rates of 7.5, 6.1, 7.5 and 7.9 cm yr-1, respectively, were recorded during four consecutive years. In winter elongation rates of fronds were rather low. Elongation did not seem to be affected by frond length, the self-shading effect of the canopy, or changes in depth. Cuts resulting from grazing were frequent on fronds through the year, decreasing significantly with increasing depth. Sheared fronds regenerated promptly, independent of season or height at which the cut was made. For commercial purposes the best season for harvesting is summer, which is the period of maximum standing stock, infertility, and calm warm waters that provide easier working conditions for divers. 相似文献
14.
Hossam Samir Ibrahim 《Journal of Coastal Conservation》2013,17(3):601-613
Coastal areas are among the most highly populated, most exploited areas and vulnerable ecosystems in the world. How these interface areas between terrestrial and marine environments can effectively planned and managed has proved to be extremely challenging. Integrated Coastal Zone Management (ICZM) has been promoted as a potential panacea for the effective planning and management of these areas. However achieving such goals for ICZM is complex because of the many human activities and diverse regulatory regimes in coastal areas requires effective integration along many dimensions. Within the context of the developing world, which is often characterised by highly centralised governance systems combined with a lack of effective public and stakeholder participation in planning delivering an effective ICZM, which is drawn from collaborative planning ideas has proved particularly problematic. Furthermore within these countries there have been few critical and analytical evaluations of why ICZM experiments have failed. This paper seeks to begin to address this gap by suggesting that Actor Network Theory (ANT) is an appropriate analytical framework to critically evaluate why ICZM initiatives in Egypt, at both the national and local level, have been relatively unsuccessful. The critical evaluation leads to some practical recommendations that could help to enhance the implementation of ICZM in Egypt. 相似文献
15.
The Countryside Council for Wales (CCW) is developing a management framework with the primary aim of restoring favourable
conservation status to the sand dune resource of Wales. It will take onboard the requirements of both national and international
conservation legislation and will also help CCW integrate its responsibilities for biodiversity, geodiversity, landscape,
access and recreation for this habitat. In order to achieve certain conservation goals it will be necessary to have in place
a variety of different types of management ranging from non- or minimal intervention through to intensive single species management
and habitat re-creation. However, it will not provide a comprehensive framework for all aspects of site management, but only
those that are deemed to be of strategic importance, and have significance within an all-Wales perspective for their nature
conservation importance. 相似文献
16.
Karim Nassar Hassan Fath Wael Elham Mahmod Ali Masria Kazuo Nadaoka Abdelazim Negm 《Journal of Coastal Conservation》2018,22(6):1057-1083
This paper introduces an appropriate visualization of how to effectively digitize, quantify and predict shoreline kinematics changes. The method relies mainly on the coupling of Geographic Information System (GIS) with Digital Shoreline Analysis System (DSAS). The North Sinai coast in Egypt is selected as a case study. The proposed technique is applied over a quarter-centennial period of 27 years (1989–2016). However, the years 2025, 2035, and 2050 are used for prediction purpose. Histogram threshold of band 5, Histogram threshold of band ratio, and Tasselled Cap Transformation (TCT) are initially tempted as semi-automatic shoreline extraction techniques for Landsat ETM 2010 imagery. Among of them, the TCT is found superior as a digitizing technique that attains the least normalized root mean square errors with the corresponding field data in 2010. Meanwhile, the shoreline change rates in the form of erosion/accretion patterns are automatically quantified by four statistical parameters functioned in DSAS coding. Those, namely end point rate (EPR), net shoreline movement (NSM), linear regression rate (LRR), and least median of squares (LMS). On the basis of the LRR and EPR results, this study offers to the coastal managers a highly reliable decision-support-algorism that can dynamically assist in elaborating strategies to curtail the non-affirmative consequences due to the erosion/accretion of the shoreline. 相似文献
17.
18.
J. Ojeda Zújar L. Borgniet A. M. Pérez Romero J. F. Loder 《Journal of Coastal Conservation》2002,8(1):69-76
This contribution deals with the use of different sources of data (field surveys with total station and GPS, air photographs
and topographic maps) as well as their integrated digital treatment in a GIS context to quantify the morphological changes
in a ridge of coastal dunes in the southwest of Spain. The results show very high and increm enting rates of foredune retreat
significant losses of foredune surface and a clear negative sedimentary balance (lowering and inland migration) in its recent
evolution (1979–1996). Two processes can explain this evolution: (1) marine erosion and (2) the reactivation of aeolian deflation.
The combined use of GPS (code/phase) and soft-copy photogrammetry seem to provide the best for monitoring future changes. 相似文献
19.
Rosana Ouréns Luis Fernández María Fernández-Boán Inés Naya Juan Freire 《Marine Biology》2013,160(9):2413-2423
We studied the spatial variability in the size at first maturity and the reproductive cycle of Paracentrotus lividus in Galicia, contributing key information for the exploitation and management of this resource. The size at maturity varied between 20.4 (±1.2 SE) mm and 27.9 ± 1.2 mm and was smaller in areas of low population density where sea urchins do not form patches. Using a nonlinear model, we analysed the effect of depth, body size, sex and population density on the temporal pattern of the gonad index. The maximum and minimum indices were obtained at 4 m depth in the months before and after the spring spawning, respectively. The depth also affected the cycle phase, and the sea urchins at 4 m depth spawned 9.4 ± 3.0 days later than the sea urchins at 8 m depth and 20.5 ± 3.0 days later than those at 12 m depth. Moreover, the sea urchins living in patches showed a slight increase in gonad size as a consequence of the better-quality habitat. This shows that there is no intraspecific competition in this area despite the high population densities reached (18.5 kg m?2). 相似文献
20.
Portugal is strongly vulnerable to sea hazards due to intense vessel traffic and sea conditions. The southwest region off the Iberian Peninsula lies in the main route from the Mediterranean and Southern Hemisphere to the Northern Europe, causing a ship concentration in a narrow band off Cape S?o Vicente. Tankers represent a significant part of the vessel traffic and the occurrence of oil spills cannot be disregarded. Cape S?o Vicente region is part of a Natural Park with 110 Km of coastline, integrated in the European Natura 2000 network and its socio-economic context is closely related with sea resources exploitation, particularly fishing and tourism. Recognizing the importance of accurate information systems for the decision making process in an oil spill situation, this work presents the development of an integrated tool to support the process in the Algarve coast. The system relies in a regional operational mathematical model based on the MOHID modelling system. The system core is composed by three models (3D hydrodynamics, wave and Lagrangian transport) all linked in the same system and exchanging information in real time. Oil advection and weathering processes are coupled to the Lagragian transport model. The overall operational system includes external operational data products as inputs, to ensure a successful validation of the results. The system is linked to stakeholders and response authorities using a geographic referenced database based on Mapserver technology that will include relevant information for oil spill management. 相似文献