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171.
Floating marine debris, particularly derelict fishing gear, is a hazard to fish, marine mammals, turtles, sea birds, coral reefs, and even human activities. To ameliorate the economic and environmental impact of marine debris, we need to efficiently locate and retrieve dangerous debris at sea. Guided by satellite-derived information, we made four flights north of Hawaii in March and April 2005. During these aerial surveys, we observed over 1800 individual pieces of debris, including 122 derelict fishing nets. The largest debris concentrations were found just north of the North Pacific Transition Zone Chlorophyll Front (TZCF) within the North Pacific Subtropical Convergence Zone (STCZ). Debris densities were significantly correlated with sea-surface temperature (SST), chlorophyll-a concentration (Chla), and the gradient of Chla. A Debris Estimated Likelihood Index (DELI) was developed to predict where high concentrations of debris would be most likely in the North Pacific during spring and early summer.  相似文献   
172.
Two biotic indices, ATZI Marine Biotic Index (AMBI) and Benthic Quality Index (BQI) have been recently introduced within the EC Water Framework Directive to assess the quality of marine habitats: both are based on sensitivity/tolerance classification and quantitative information on the composition of soft-bottom macrofauna. Their performance, especially with regard to sampling effort was assessed based on two data sets collected in Southern Baltic and one from the Gulf of Lions Mediterranean. AMBI was not affected by sampling effort but BQI was. Two modifications were proposed for BQI (i.e., BQI) (1) the removal of the scaling term (i.e., BQI(W)), and (2) the replacement of the scaling term by different scaling term (i.e., BQI(ES)). Both modified BQIs were largely independent of sampling effort. Variability was slightly lower for BQI(W) than for BQI(ES). BQI was highly correlated with BQI(W) and with BQI(ES) both in the Southern Baltic and in the Gulf of Lions. However, the proportions of stations, which were not attributed the same ecological quality status (EcoQ) when using BQI and its two modified forms were always high. Differences in ecological classification were mostly due to the scales used to infer EcoQ. Based on this study we recommend to use BQI(ES) in future studies because it apparently constitutes the best compromise in (1) being independent of sampling effort, (2) limiting the variability in computation in relation with sampling effort, (3) being correlated with BQI and corresponding EcoQ.  相似文献   
173.
Benthic status of 28 near-shore, artisanal, coral reef fishing grounds in the central Philippines was assessed (2000-2002) together with surveys of the seahorse, Hippocampus comes. Our measures of benthic quality and seahorse densities reveal some of the most degraded coral reefs in the world. Abiotic structure dominated the fishing grounds: 69% of the benthos comprised rubble (32%), sand/silt (28%) and dead coral (9%). Predominant biotic structure included live coral (12%) and Sargassum (11%). Rubble cover increased with increasing distance from municipal enforcement centers and coincided with substantial blast fishing in this region of the Philippines. Over 2 years, we measured a significant decrease in benthic 'heterogeneity' and a 16% increase in rubble cover. Poor benthic quality was concomitant with extremely low seahorse densities (524 fish per km(2)). Spatial management, such as marine reserves, may help to minimize habitat damage and to rebuild depleted populations of seahorses and other reef fauna.  相似文献   
174.
The article explores whether marine biodiversity mappings can contribute to the mapping of the material basis of Sami culture. Four different mapping practices are analysed in the article, all related to the seascape in the Lyngen fjord (Lyngenfjorden) in northern Norway. Initiatives undertaken by the Norwegian Directorate of Fisheries and the Institute of Marine Research (IMR) to map cod spawning grounds, and by the Sami Rights Commission (SRC) to map customary use of a fjord are compared with local fishing practices. Although the seascape was initially mapped to find spawning grounds (the IMR and the Directorate) and to record social practices (the Directorate and the SRC), the outcomes also express social relations between the mappers and the mapped materials. Whereas the mappings that included fishermen's relations with fishing grounds are compatible with each other, the marine scientists' mapping documented biodiversity independent of local relations with it. The author argues that the marine environment should be seen as expressing social relations between groups of people and certain materialities instead of as separated in natural and social layers. Thus, even though marine biodiversity mapping practices reveal biodiversity in Sami settlement areas, they inform little about the material basis of Sami culture.  相似文献   
175.
基于中国南极磷虾渔业科学观察员收集的数据,利用广义可加模型(GAM),对2009—2010渔季和2010—2011渔季夏秋季南奥克尼群岛周边水域南极磷虾渔场时空分布及其与表温和海况之间的关系进行了研究。结果表明,GAM模型对单位捕捞努力量渔获量(CPUE)总偏差解释率为41.78%,其中贡献最大的为月份,贡献率为15.53%;奥克尼群岛水域CPUE分布模式均有明显的月份差异。1月份平均CPUE值最低,而4月份平均CPUE值最高,各月份平均CPUE存在显著性差异。渔场主要集中在60°12′—60°30′S,45°30′—47°30′W。南极磷虾作业渔场的适宜海水表温范围为0.1—1.8℃,最适表温范围为0.5—1.5℃。各海况等级间及不同渔船的平均CPUE均存在显著性差异。逐步GAM模型分析结果表明,影响CPUE的因子按重要性从大到小依次为月份、渔船、经度、海表温度、纬度和海况。  相似文献   
176.
我国渔港沉积物的重金属污染及潜在生态风险评价   总被引:6,自引:1,他引:5  
分析了青岛、宁波、舟山、厦门、深圳、珠海、澳门、茂名和三亚共9个渔港(包括综合港口区)表层沉积物中的Cd、Cu、Pb、Zn、Co和Ni等典型重金属元素的含量,探讨了其可能的来源。采用沉积物质量基准法和Hakanson潜在生态风险指数法,评价了各渔港重金属的污染状况和潜在生态风险。结果表明:(1)渔港沉积物中重金属Cu、Zn、Pb和Cd的富集较为严重,位于珠江三角洲的渔港重金属含量显著高于其他渔港,尤其是Cu和Zn,最高含量分别达到1249mg/kg和664mg/kg,而Cd和Pb的污染也不容忽视;(2)珠三角渔港具“高”或“中等”潜在重金属生态风险,其中Cu和Cd具有高的潜在生态风险,其他渔港均属低生态风险,渔港总的潜在生态风险由高至低顺序为:澳门〉深圳〉珠海〉茂名〉三亚〉厦门〉青岛〉宁波〉舟山;(3)渔港沉积物中重金属主要来自工业废水、生活污水、污灌土壤以及大气沉降的污染和渔船防护漆的使用。而船体防护漆中Cu/氧化亚铜的大量使用是渔港中Cu污染的主要来源。  相似文献   
177.
This article examines the interplay of gender, caste‐religion, and household survival strategy formation among Christian and Muslim fisher folk in the south Indian state of Kerala. The methodology consisted of surveys of forty‐one households in two villages in which data pertaining to male and female work patterns and other household level data were collected in the summer of 1999. My analysis demonstrates how particular ideologies of gender and work associated with different caste‐religion communities influence the strategies individual households adopt. I discuss intersections between gender and caste‐religion with other socioeconomic factors and illustrate the manner in which gender then gets reworked in particular ways in the course of economic transformation.  相似文献   
178.
在分析5年来云南省开展县域地灾调查工作成果的基础上,认为该项工作在本省地灾防治工作中至少发挥了6个方面的作用:(1)显著减少了群死群伤灾害的发生;(2)深入宣传普及了防灾知识;(3)为合理开发利用国土资源提供了环境地质依据;(4)为地质灾害防治纳入国民经济及社会发展规划奠定了基础;(5)为科学管理地灾防治工作创造了条件;(6)有利于强化地灾防治工作的组织协调。同时也指出,目前县域地灾调查工作的进度尚与地灾防治工作的迫切需要不相适应,各级政府应切实重视、想方设法、积极推进县域地灾调查工作。作者就如何推进云南省县域地灾调查工作及进一步发挥县域地灾调查成果的作用,提出了若干建议。  相似文献   
179.
2001年11月14日中国西部青藏高原发生昆仑山口西8.1级强震,2003年9月27日新疆北部的中俄蒙交界再次发生7.9级强震,这两次特大地震时隔不到2年,引起了地震学界的广泛关注和深入研究。本文结合前人的地震震源破裂过程研究结果,利用物理学中的科里奥利力效应对这两次地震序列表现出的不同震级特征进行了一种可能的力学解释。  相似文献   
180.
陈东  陈兆林 《海岸工程》2006,25(4):60-62
为了打造帆船之都,促进青岛旅游业和旅游经济的发展,提出了利用休渔期,选择安全性能好的渔船和经过专门培训的渔民搞海上旅游观光、垂钓并发展渔村餐饮业,以解决渔民增收和生活问题,使旅游码头和渔港码头优势互补,共同发展,为青岛旅游业开辟另一条新路。  相似文献   
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