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作为我国最早建立的五个国家级海洋自然保护区之一,南麂列岛有着独特的特点,在该海域进行海洋资源开发的过程中应科学合理。文章结合南麂列岛的生态环境现状及其他相关特征,对在该海域建设海洋牧场的意义和可行性进行了分析并提出相关建议。 相似文献
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<正> 一、南麂岛的地理和自然环境南麂列岛的中心点,位于北纬27°27′、东经121°05′,由大小23个岛屿,71个明暗礁(1986年4月再加1个人造鱼礁)组成。分布在162平方公里的海面上。全列岛陆上面积共12平方公里(其中南麂本岛7平方公里),有常住人口的三个岛屿(1986年人口数2509人)是南麂本岛、竹屿、大擂。苍、平两县渔民季节性住岛生产的也有三个岛屿,是门屿、柴屿、平屿,可以住人,但现在无人居住的荒岛有6个,是后麂、龙头屿、破屿、尖屿、上马鞍、下 相似文献
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作为我国最早建立的5个国家级海洋自然保护区之一,南麂列岛有着独特的特点,在该海域进行海洋资源开发应遵循科学合理的原则。文章结合南麂列岛的生态环境现状及其他相关特征,分析了在该海域建设海洋牧场的意义和可行性,并提出相关建议。 相似文献
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根据2013年11月、2014年2月、5月、8月对南麂列岛岩相潮间带7个断面进行的生物资源定量和定性调查所获得的软体动物资料,研究了该区域软体动物的种类组成和数量分布特征。结果显示:(1)共鉴定出软体动物种类63种,隶属于3纲13目34科52属。春、夏、秋、冬季出现的种类数分别是48种、48种、45种、41种。(2)不同季节软体动物资源数量不同,在个体数上是春季>秋季>冬季>夏季;在重量上则是春季>秋季>夏季>冬季;软体动物平均个体数和生物量分别为506.5个/m2和801.54 g/m2,且以春季为最大,冬季为最小。(3)不同潮区的软体动物平均个体数不同,具体是中潮区>低潮区>高潮区;生物量差异也很明显,具体是低潮区>中潮区>高潮区。(4)不同季节的优势种差异较大,但条纹隔贻贝是一年四季共有的第一大优势种。研究表明,由于受海流、地形、风浪等环境因素的影响,南麂列岛潮间带软体动物在不同季节、不同断面的分布差异较大。同时,通过与历史资料的对比发现,近二十年来,南麂列岛软体动物的物种数及数量有一定程度的减少。 相似文献
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基于碳、氮稳定同位素技术的大亚湾紫海胆食性分析 总被引:2,自引:0,他引:2
为掌握大亚湾紫海胆(Heliocidaris crassispina)的食性特征,应用碳、氮稳定同位素技术对2015年8月所采集紫海胆样本的稳定同位素特征、营养级和食性特征进行了初步研究。结果表明,大亚湾紫海胆平均δ~(13)C值为-(13.35±1.21)‰,平均δ~(15)N值为(9.14±0.38)‰,平均营养级为2.11±0.14。不同壳径紫海胆之间的碳、氮稳定同位素比值无显著性差异(P0.05)。大亚湾海域紫海胆生活环境周围生物δ~(13)C值分布范围为-20.76‰~-9.93‰,δ~(15)N值分布范围为-0.16‰~14.99‰,营养级范围为1.34~3.77。大亚湾主要生物种类可划分为悬浮物、初级生产者和初级消费者、次级消费者、顶级消费者4个营养组群,其中紫海胆属于次级消费者。8月份调查海域珊瑚稀少,大型海藻密度低且死亡降解形成颗粒有机物(Particulate Organic Matter,POM),陆源POM随降雨大量流入大亚湾,导致紫海胆在8月份摄食偏向碎屑食物链,主要食物来源为POM,平均贡献率为67.3%;其余摄食种类为沉积物(Sediment Organic Matter,SOM)、裂叶马尾藻(Scagassum siliquastrum)、底栖硅藻、浮游动物及浮游植物,平均贡献率分别为9.7%、9.3%、6.7%、3.7%及3.3%。大亚湾紫海胆摄食种类与其栖息地底栖生物存在重叠,具有一定的食物竞争关系。研究表明,分析紫海胆食性特征对了解其所在生态系统中营养级水平具有重要意义。 相似文献
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Kim Birnie‐Gauvin David Costantini Steven J Cooke William G Willmore 《Fish and Fisheries》2017,18(5):928-942
Oxidative stress results from an imbalance between the production of reactive oxygen species and the antioxidants defences, in favour of the former. In recent years, the association between oxidative processes, environmental change and life histories has received much attention. However, most studies have focused on avian and mammalian taxonomic groups, with less attention given to fish, despite their ecological and socio‐economic relevance. Here we present a review of the extrinsic and intrinsic factors that influence oxidative processes in fish, using a comparative and evolutionary approach. We demonstrate that oxidative stress plays a key role in shaping fish's responses to environmental change as well as life history strategies. We focus on representative examples to compare and contrast how levels of oxidative stress respond to changes in temperature, salinity and oxygen availability. Furthermore, we describe how emerging threats (i.e. pollution) affect oxidative stress parameters in fish. Oxidative stress indicators are increasingly being used as biomarkers to understand the mechanisms of various human‐induced stressors, but also to understand the physiological consequences of how animals are distributed in space and time and influenced by different life stages. Despite the expansion of the field of ecological oxidative stress, we are only beginning to understand the complex ways in which oxidative stress may interact with both extrinsic and intrinsic factors in fish. We conclude with a research agenda for oxidative research on fish and note that there is need for further research particularly in the area of life history strategies and ecological implications of oxidative status, as this type of research has the potential to help us understand patterns and dynamics relevant to fish conservation. 相似文献
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The economic benefits of an aquaculture-hydroponic integrated system are evaluated using a hydroponic-lettuce and barramundi fish production system as a case study. Technical data were obtained for a case study farm located at Port Stephens, New South Wales, Australia. The net present values of annual cash flows over a 10-year planning horizon were determined for barramundi and lettuce production as stand-alone units, and alternatively as integrated units, using a capital budgeting framework. Integrated production enables barramundi effluent to be used as a source of nutrients for the lettuce production. This results in an increase in net benefits equal to the reduction in barramundi effluent disposal costs, and the saving of some water and nutrient costs of the lettuce system. 相似文献