...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>水産研究·教育機構研究報告 >Stocks and fisheries of asari in Japan
【24h】

Stocks and fisheries of asari in Japan

机译：在日本股票和渔业asari

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Asari clam is one of the most important fishery resources in Japan. The clam has been utilized as not only a food but also a recreational harvestable species. Main habitat of the asari extends from tidal area to shallow subtidal area of sandy soft bottom. Asari is harvested by hand raking or short-handled basket raking in tidal areas and long-handled basket raking, dredging, helmet diving in subtidal areas. Major areas of asari harvest are Tokyo Bay, Mikawa Bay, Ise Bay, Suo Nada and Ariake Bay. Annual harvest of the asari in the major areas, however, decreased largely after late 1980s except Mikawa Bay. Stock decline of natural asari is remarkable and seriously problematic for coastal fisheries in Japan. Along with application of the various countermeasures intended to restore the natural stocks of asari, a number of factors have been discussed to be responsible for the asari decline. Some of these are decrease of suitable habitat areas, deterioration of water and substrate quality, erosion of theclams by strong wave disturbance, new predators and parasites, oligotrophication, and excess harvesting. We still have not determined significant factors responsible for the asari decline in Japan. In the discussed factors, we compared the effect of five factors; blue tide, river flood, strong wave disturbance, infection of sea spider, and hypoxia on clam larvae, based on the studies in Tokyo Bay. The impacts (mortalities) of the factors for the total asari stock by the blue tide in Sanbanze in 2008, the river flood in Sanbanze in 2007, winter wave mortality in the three areas in 2009-2010, and infection of sea spider in Kisarazu in 2009 were calculated to be 0.16, 0.07, 0.95, 0.30, respectively. Among these factors, winter wave mortality showed the most significant effect on the asari stock in Tokyo Bay. Comparing the properties of the estimated factors, the factors that affected wider areas and longer period with higher mortality were supposed to give severer impact for the asari stock. In order totake effective countermeasures for the decline of asari stock in Japan, further assessment of the impact of the suspected factors is required to be progressed.
机译：Asari蛤是其中一个最重要的渔业在日本的资源。不仅食物也是一种娱乐收获的物种。从潮汐区域延伸到浅潮下的区域桑迪软底。在潮汐斜斜或short-handled篮子地区和长柄篮子斜、疏浚、头盔潜水在潮下的地区。asari收获东京湾,Mikawa湾,伊势湾,锁和有明湾。然而,asari主要地区的下降主要在1980年代末,除了Mikawa湾。自然asari显著下降沿海渔业的严重问题日本。对策旨在恢复自然asari股票,很多因素负责asari讨论下降。水和栖息地,恶化底物质量、侵蚀theclams的强劲波扰动,新食肉动物和寄生虫,oligotrophication,多余的收获。仍然没有显著的因素决定的负责在日本asari下降。讨论的因素,我们比较的影响五个因素;海蜘蛛的扰动、感染和缺氧蛤仔,基于研究在东京湾。总asari股票的蓝色潮汐Sanbanze 2008年,这条河洪水在Sanbanze2007年冬季波死亡率在三个领域2009 - 2010年的海蜘蛛和感染2009年木计算是0.16,分别为0.07,0.95,0.30。因素,冬季波死亡率显示最多显著的影响在asari股票在东京湾。因素,影响的因素更广泛的领域和较高的长期死亡率应该给asari强烈的影响股票。asari下降的股票在日本,进一步评估怀疑的影响因素需要进步。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号