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281.
《Marine Policy》2015
The world׳s eel fisheries are in a state of crisis. While an increasing number of studies have documented the biophysical dynamics of the decrease in eel populations in Canada and around the world, studies documenting fishing practices, fisheries management, and the impact of eel declines on the livelihoods of fishermen are still rare. This paper aims to contribute to this discussion by examining the American eel (Anguilla rostrata) fishery in the St. Lawrence River Estuary, positioning it within larger historical, economic, and socio-environmental contexts. More particularly, it explores the issues these fishermen face as a consequence of the declining eel population, changing management practices, global trends in eel commercialization, and initiatives taken to promote eel fishing and the landscape that surrounds it as an important component of natural and cultural heritage. It is argued that these changes, many of which have been amplified by neoliberal policy shifts, have contributed to the marginalization of eel fishers and are making their future increasingly uncertain. 相似文献
282.
《Norsk geografisk tidsskrift. Norwegian journal of geography》2012,66(4):207-216
The multiple interfaces of the European Landscape Convention were the topic of a roundtable panel discussion held at the meeting of the Permanent European Conference for the Study of the Rural Landscape in September 2006. The roundtable was convened by Kenneth R. Olwig, who together with four other speakers presented the main topics for discussion. Their presentations are given here as a series of short articles. Initially a brief historical background and the main provisions of the European Landscape Convention (Florence Convention) of 2000, in force 2004, are presented. The interfaces with law, landscape ecology, heritage, and globalisation are then successively discussed. Finally, the European Landscape Convention itself is examined as a discursive interface, with contradictory as well as synergetic aspects. 相似文献
283.
《Norsk geografisk tidsskrift. Norwegian journal of geography》2012,66(4):213-226
Recently, increased attention has been paid to the importance of everyday landscapes in the Western world, and a stronger political will to involve local participation in planning processes has emerged. The authors discuss the implementation of the political will to engage the Norwegian public in local heritage planning and whether or not this new role can have a mobilising effect on heritage protection. In Norway, cultural heritage managers have established methods for identifying valuable heritage assets in cultural historic landscapes. As increased responsibility for cultural heritage management is given to municipalities, more municipalities are making their own heritage plans to improve local heritage management. The article investigates how cultural heritage management in everyday landscapes is taking place, how heritage plans are developed, how local knowledge is involved, and what assets local residents appreciate in their environment, based on an in-depth study of two medium-sized Norwegian regional towns. The results show that local stakeholders were often invited to participate in planning processes, but that their contributions were largely kept out of official plans at the final stage. Further, the study revealed that memories and personal histories related to heritage appreciations are important elements in building identity, both at a personal level and at a local level. 相似文献
284.
《Norsk geografisk tidsskrift. Norwegian journal of geography》2012,66(3):121-134
Part of the Vega archipelago in north-western Norway is a cultural landscape listed as a UNESCO World Heritage site. Its buffer zone comprises most of the main island of Vega, where agriculture is an important land use. The authors describe interdisciplinary research carried out in the buffer zone. The research revealed the significant role of agriculture for the maintenance of the traditional open coastal landscape. The finding was further underlined by the fact that many visitors to the site never reach the outer archipelago, which is the core of the listed site. Based on interpretations of aerial photographs, land cover maps were produced for three cross-sections in time (1965, 1986, and 2009). A further reclassification of the land cover was performed to capture the change in openness due to change in land cover. Viewshed maps of each building found on the aerial photographs were overlain with the openness classes to capture the visual consequences of the buildings due to changes in land cover. A marked decrease in open land surrounding the buildings was found in the study area, which comprised Holand and Floa-Kjul in Vega Municipality, which in turn comprises the islands of the Vega archipelago. The regrowth of the land seemed to be happening regardless of building category. 相似文献
285.
中国自然文化遗产的价值体系及保护利用 总被引:1,自引:0,他引:1
对自然文化遗产价值的正确认识是处理遗产地保护和利用关系的基础,也是解决遗产地"城市化、商业化、人工化"的前提。本文在梳理国内外对自然文化遗产价值的诸多认识的基础上,依据系统论观点,提出了中国自然文化遗产价值是由"本底价值、直接应用价值和间接衍生价值"构成的"价值体系"。该体系具有明显的层次性,其中本底价值是所有价值存在的基础,这决定了遗产资源必须在保护的前提下才能合理利用;该体系也有空间性,三种价值主要分别存在于遗产地范围以内、遗产地及相邻区域、遗产地范围以外的更大的区域。于是,对自然文化遗产的保护和利用要坚持三个基本原则:严格保护本底价值,确保遗产的真实性和完整性不受损害;适度利用直接应用价值,做到功能综合利用、产品综合开发、产业综合发展;大力发展间接衍生价值,充分发挥其空间结构关联效应和产业发展乘数效应,从而达到带动遗产地所在区域社会、经济发展的目的。 相似文献
286.
Based on reconstructions of precipitation events from the rain and snowfall archives of the Qing Dynasty (1736–1911),the drought/flood index data mainly derived from Chinese local gazettes from 1736–2000, and the observational data gathered since 1951,the spatial patterns of monsoon rainbands are analyzed at different time scales.Findings indicate that monsoon rainfall in northern China and the middle-lower reaches of the Yangtze River have significant inter-annual(e.g.,5–7-yr and 2–4-yr)as well as inter-de... 相似文献
287.
H. Kars 《Journal of Geochemical Exploration》1998,62(1-3)
Empirical evidence has shown that industrialization and changes in agricultural practices have caused worldwide dramatic changes in the burial conditions of the archaeological remains. The current understanding of the problem, however, is not sufficiently advanced, which hinders adequate measures to prevent a tremendous loss of archaeological information. In the beginning of the nineties, research programmes were started to gain insight into the deterioration of different kinds of organic and inorganic components, representing a great variety of archaeomaterials. Knowledge of the present-day preservation condition of the remains will create the scientific basis for an environmental risk assessment of archaeological sites. It also will be the basis for developing strategies for the monitoring of a well-defined number of endangered sites. Such a monitoring system particularly is needed at places where geotechnical measures, like the local up-levelling of the soil and the creation of an artificially high ground water table, have been carried out to protect the archaeological heritage. 相似文献
288.
Abstract The Easter 1998 flood was the largest flood event in the gauged record of many basins of the English Midlands. Flood frequency analysis, using such gauged records only, placed the 1998 event at a return period of over 100 years on several basins. However a review of historical (pre-gauged) flooding on some rivers gives a different perspective. Examples are given of the use of historical flood information on the River Leam, the River Wreake at Melton Mowbray, the River Sence (tributary to the River Soar) and the River Frome at Stroud. The cost of acquiring such historical flood data is trivial in comparison to gauged data, but the benefits are demonstrated as significant. In particular, historical flood data provide a better basis for risk assessment and planning on flood plains through revised estimates of flood discharge and depth. 相似文献
289.
1856年黔江小南海地震初探 总被引:1,自引:0,他引:1
对小南海地震发生的地质背景、成因机制、地震灾害及其遗迹进行了论述,作为自然遗产应得到充分地保护。 相似文献
290.
Rising in the Neogene hills of the Mallakaster, the rivers Seman and Vjosa have built up two large joint deltas on the Albanian Adriatic shore. This shoreline is characterized by a low sandy coast with bars and spits. Changes in the river courses and migration of the mouths of the deltas were rapid and numerous from the Holocene period until the beginning of drainage works in the 1950s. The drainage basins of the two rivers are developed in soft clastic rocks (flysch and molasse) in the proportion of 71·4 per cent for the Seman and 44·8 per cent for the Vjosa. Both rivers carry abundant sediment loads, amounting to 6·7 × 106 tonnes per year for the Vjosa and 13·2 × 106 tonnes per year for the Seman. This is the reason why the alluvial deposits of the Seman have built up two‐thirds of the alluvial plain. The use of a SPOT image dated 25 May 1995 (HRV 3 081‐268) enabled us to view the effects of coastal and fluvial dynamics, the role of neotectonics as well as the predominance of the plume of suspended sediment of the Seman river. Using this image, a geomorphological map was drawn, which identifies the palaeochannels of the Seman and the Vjosa. In order to date those palaeochannels we have made an archaeological inventory from oral and written published information. The location of the sites we studied was checked systematically in the field. The mediaeval and Ottoman archives kept in Tirana also provided substantial information, as well as the reconstitution of the evolution of the shoreline between 1870 and 1990, carried out using an inventory of topographic maps. This work allowed us to reconstitute the progression of the deltas of the Seman and the Vjosa since antiquity. We may then infer that from antiquity up to the Middle Ages, the deltas of the Seman and the Vjosa both progressed very moderately and in a comparable way. However, at the end of the 15th century the Seman underwent a major change in its course, through a southward migration of the river. The natural processes of alluviation and changes in the river courses seem to have been accelerated as agricultural exploitation of the Neogene hills that form most of the drainage basin of the Seman increased. This exploitation is linked with the massive exportation of cereal from the port of Skela e Pirgut, which started in the 14th century. It appears that the 20th century has been the period of the largest progression of the deltas during historical times. The speed of progression increased as early as the beginning of the century, as a result of the rapid growth of the rural population densities. Soil erosion from arable fields increased catchment sediment yields to promote rapid changes in the river courses. This resulted in abandonment of deltaic mouths, a phenomenon leading to a straightening of the coast. Thus to the south of the present mouth of the Seman the coast receded by 7 to 30 m per year between 1968 and 1990 as a result of the abandonment of a mouth. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献