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91.
Abstract. Four individual dugongs Dugong dugong , MÜLLER, 1776 were tracked with buoyant, tethered. conventional and satellite radio transmitters. The dugongs three adult females and one immature male were encircled with a net at a catch site near Haruku Island, East Indonesia, and tracked for between 41 and 285 days. The animals showed individualistic patterns of movement, moving between 2 and 3 core areas, travelling between 17 and 65 km from the site of capture. One adult female spent most of the time at two distinct inshore seagrass beds separated by about 17 km; she made five trips between the two sites. Two other females made separate trips to two distinct sites, one of them returning to the catch site at Haruku Island. The immature male journeyed between two areas about 65 km apart. completing the journey in four days. The patterns of movement confirmed a practice of regular recropping of restricted grazing swards by small, loose feeding assemblages rather than fixed herds with a strong social bond. Mean home ranges covered 4.1 km2 50% harmonic mean and 43.4 km2 95% harmonic mean. 相似文献
92.
本文以“社交媒体多层次信息流”为概念框架,分析了四川九寨沟7.0级地震发生后,个人、当地的组织、宏观层面的主流媒体使用社交媒体所发挥的作用。通过对微博的数据进行挖掘分析,总结出地震灾害发生后社交媒体所具有的5项功能:人际之间的交流,地方政府、本土组织以及当地媒体的传播渠道,大众传媒信息发布的渠道,信息的收集和分享,微观、中观以及宏观各主体间沟通的渠道。在强震发生后社交媒体有巨大的传播潜力,本文的研究成果对未来大震发生后如何利用社交媒体来应对灾害有一定的借鉴意义。 相似文献
93.
Hong Hao 《地震工程与结构动力学》1998,27(1):91-103
During the recent major earthquakes, some bridges suffered severe damage due to the pull-off-and-drop collapse of their decks. This is due to the large differential movements of the adjacent spans of bridges during strong shaking compared to the seating lengths provided. The differential movements are primarily due to the different vibration properties of adjacent spans and non-uniform ground excitations at the bridge supports. This paper analyses the effects of various bridge and ground motion parameters on the required seating lengths for bridge decks to prevent the pull-off-and-drop collapse. The random vibration method is used in the analysis. A two-span bridge model with different span lengths and vibration frequencies and subjected to various spatially varying ground excitations is analysed. Non-uniform spatial ground motions are modelled by the filtered Tajimi–Kanai power spectral density function and an empirical coherency function. Ground motions with different intensities, different cross-correlations and different site conditions are considered in the study. The required seating lengths for bridge decks are calculated. Numerical results are presented and discussed with respect to different bridge vibration and ground motion properties. © 1998 John Wiley & Sons, Ltd. 相似文献
94.
《Marine Policy》2017
Traditionally, the ‘social licence to operate’ (SLO) refers to the societal expectations imposed on corporate and commercial activities, often displayed by the willingness for corporations to go beyond the requirements of formal regulations. Alternatively, this paper investigates the emerging influence of the SLO in shaping government decisions regarding the use and impact of the marine environment and its resources. Using expert interviews, text analysis and case study analysis, this research delineated the contemporary SLO as it has manifested in Australian marine governance, with the results indicating that this is potentially occurring at a pace faster than can be systematically reacted to within the current political decision-making processes. Under these emerging conditions, the risk has been identified that traditional government decision-making and stakeholder consultation processes are lagging in their capacity to adapt to ensure that public policy processes can support and engage in this shifting dialogue and ensure the influence of information is appropriately weighted. This research highlights an emerging adjustment of community presence in marine governance and the immediate complexities and challenges this creates for government decision-making. In particular, it begins to explore the interaction of differing information, how this information is carried through communication channels, stakeholder behaviour, approaches to withholding or granting a SLO and the responsibility this carries. 相似文献
95.
《Marine Policy》2017
As climate change continues to pose a major threat to the well-being of both people and the environment, adaptation to its negative effects has moved to the forefront among occupations that rely on natural resources for their livelihood. As one of the main occupational groups who are dependent on nature, fishermen are expected to experience many new challenges from the changing climate. Though an adequate amount of scientific research on climate change has been carried out, few studies have explored the social circumstances of the issue, particularly in the context of small scale fishermen. This paper aims to address this gap. Aspects such as risks reduction, social relationships, climate change knowledge, alternative skills, involvement in adaptation planning and access to credit are recommended to be considered as these are found to provide synergy for social adaptation, and it is hoped that such recommendation strategies will assist stakeholders in generating and engendering effective adaptation strategies for small-scale fishermen. 相似文献
96.
《Marine Policy》2017
Global coral reef related tourism is one of the most significant examples of nature-based tourism from a single ecosystem. Coral reefs attract foreign and domestic visitors and generate revenues, including foreign exchange earnings, in over 100 countries and territories. Understanding the full value of coral reefs to tourism, and the spatial distribution of these values, provides an important incentive for sustainable reef management. In the current work, global data from multiple sources, including social media and crowd-sourced datasets, were used to estimate and map two distinct components of reef value. The first component is local “reef-adjacent” value, an overarching term used to capture a range of indirect benefits from coral reefs, including provision of sandy beaches, sheltered water, food, and attractive views. The second component is “on-reef” value, directly associated with in-water activities such diving and snorkelling. Tourism values were estimated as a proportion of the total visits and spending by coastal tourists within 30 km of reefs (excluding urban areas). Reef-adjacent values were set as a fixed proportion of 10% of this expenditure. On-reef values were based on the relative abundance of dive-shops and underwater photos in different countries and territories. Maps of value assigned to specific coral reef locations show considerable spatial variability across distances of just a few kilometres. Some 30% of the world's reefs are of value in the tourism sector, with a total value estimated at nearly US$36 billion, or over 9% of all coastal tourism value in the world's coral reef countries. 相似文献
97.
《Marine Policy》2017
The Netherlands was one of the first nations to introduce ITQs in their fisheries to manage national yearly Total Allowable Catches (TACs). These ITQs have gradually developed from an individual quota system in 1976 to an ITQ system in the 1980s. In 1993 the system was reformed into a co-management system. In this paper it is argued that many of the usual negative socio-economic consequences of ITQs mentioned in the literature have been largely absent, due to the embeddedness of ITQs in co-management arrangements. However, cracks have appeared lately in this combined management system, allowing an identification of its vulnerabilities. These findings show that the social and economic structure of Dutch fisheries is changing from a rather cooperative to a more competitive and exclusive system, more like conventional ITQs. 相似文献
98.
RH Bennett PD Cowley A-R Childs CG Attwood L Swart TF Næsje 《African Journal of Marine Science》2017,39(4):475-489
Understanding movement behaviour is essential for effective management of fishery species. Dart tags were used to study coastal movement patterns of white steenbras Lithognathus lithognathus, an overexploited seabream (Sparidae) in South Africa. In total, 6 962 fish (190–1 080 mm fork length) were tagged throughout the species’ distributional range, in four long-term fish-tagging programmes. The predominant behaviour recorded was residency, with relatively short-ranging movements. More than 60% of the 351 recaptured fish were recaptured within 1 km of their tagging site, some of which were at liberty in excess of three years. Most of the juveniles (93.9%), subadults (71.7%) and adults (64.0%) were recaptured within 10 km. Occasional long-distance movements of up to 800 km were recorded. Recapture distances were positively, but weakly, correlated with fish fork length (n = 257 fish measured at recapture; r2 = 0.166, p < 0.001). Low levels of connectivity among coastal areas suggest that large-scale annual spawning migrations, as previously hypothesised for this species, are unlikely, which raises the possibility of multiple spawning sites. Seventy-seven percent of L. lithognathus tagged within three marine protected areas (MPAs) were recaptured within the same MPA, suggesting that area closures provide protection for L. lithognathus through the post-estuarine juvenile, subadult and adult life stages. We confirm that the country’s current network of coastal MPAs plays a vital role in sustaining this species, and suggest that additional closures, or otherwise substantial reductions in catch rates, are necessary for the species’ recovery. 相似文献
99.
提高地震安全,减轻地震灾害造成的经济损失和人员伤亡,地震信息社会服务是不可缺少的途径。地震信息主要包括法规建设、地震监测、震害防御和应急救援资料,服务内容包括法规宣传和普及、地震灾害影响服务、工程建设监管服务和防灾避震服务等。通过地震信息社会服务,可以增强社会防灾意识,提高建设工程安全,减轻地震灾害损失。 相似文献
100.
Social memory and resilience in New Orleans 总被引:1,自引:1,他引:0
A key concept in resilience studies is that human societies can learn from hazard events and use their accumulated social
memory to better contend with future catastrophes. This article explores the deliberate referral to historical records complied
after Hurricane Betsy in 1965 and how they were used to prepare for tropical storms at the time of Hurricane Katrina in 2005.
Despite proclamations that Louisiana would not repeat its mistakes, hazards planners seriously neglected the historical record. 相似文献