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长江流域渔业水域生态保护和修复,是我国水产界共同关心的课题。长江渔业资源管理委员会办公室在生态保护和修复中坚持“重点修复、全面保护、合理利用、持续发展”的方针,在具体操作中坚持“修复与利用相结合”、“突出重点、统筹兼顾”、“衔接协调、远近结合”、“科技创新与科技先行”的原则,他们具体措施和方法做到以下几点: 相似文献
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我国赤潮频发现象分析与海藻栽培生物修复作用 总被引:11,自引:1,他引:11
In this paper, the history, main events and present status of red tide
(HAB, harmful algal blooms) along China coast in recent years were reviewed and presented. It showed that the HAB's frequency and scale, number of HAB spec
ies, percentage of toxic HAB events and the degree of damages to marine environment and economy have sharply increased in China since 1960's.
Eutrophication was key factor for high occurrence of red tide. In this paper, main causes of frequent HAB occurrence along China coast was discussed. Many factors might influence the occurrence of red tide, which included weather, climate, coastal current, tidal current, water temperature, salinity, hydrodynamic and nutrient conditions, trace metals and the variation of biological environment. Numerous evidences from all over the world revealed the linkage between the increases in nutrient loading and the occurrences of high biomass blooms. Eutrophication was one of the important causes that involved in high occurrence of HAB. The main sources of nutrients potentially stimulating HABs included terrestrial runoff, aquaculture selfpollution, atmospheric deposition, sea projects and other pollution events in the ocean. Studies showed that the input from land contaminations and the selfpollution of marine aquaculture accelerated eutrophication in coastal waters and were also important impact factors on red tide. Researches suggested that nutrient composition could affect the species composition of phytoplankton as well as the development of some HABs. The changes in nutrient supply ratios, primarily N∶P, often resulted in shifts in red tide species composition. The correlation between cysts and formation of HAB was discussed from the viewpoi
nt of transformation of cyst and vegetative cell, the effects of trace elements and other organic substances on the occurrence of HAB were presented also. It indicated that the nutrient control could be an effective way to reduce the risk of red tide occurrence. Seaweed would play an important role for decreasing marine eutrophication. Among the different methods of red tide controlling studied, seaweed biomass has received much attention due to the cost saving, low sensitivity to environmental and impurity factors, the possible contaminant recovery from the biomaterial and its elevated adsorption capacity. Cultivated seaweeds have very high rates of productivity higher than that of seaweed in its natural habits and grow well in water bodies with higher nitrogen and other nutrients. Seaweeds are able to absorb large quantities of nitrogen, phosphorus and carbon dioxide, produce large quanti
ties of oxygen, and have excellent effect on decreasing eutrophication. Large amounts of C, N and P are accumulated into seaweed tissues as they accumulate considerable biomass over a period of months or years depending on the cultivation season. When seaweeds are harvested, nutrients are removed from the sea area. An investigation was carried out for inorganic nitrogen and inorganic phosphorus concentration at Lusi Coast, Qidong County, Jiangsu Province in China, where there were about 270 hm2 for Porphyra yezoensis cultivation with eutrophic sea water in recent years. While during Porphyra yezoensis cultivation, from Sep 2003 to May 2004, the concentration of ammonium nitrogen declined form 0.511-0.778 mg·L-1 to 0.006-0.057 mg·L-1, nitrite nitrogen concentration declined from 0.010-0.040 mg·L-1 to 0.001-0.009 mg·L-1, and nitrate nitrogen concentration declined from 0.466-0.549 mg·L-1 to 0.286-0.0568 mg·L-1, the average concentration of inorganic phosphorus declined from 0.024 mg·L-1 to 0.019 mg·L-1. Furthermore, during five hours, the concentration of ammonium nitrogen in the seawater declined form 220.88 μmol·L-1 to 8.59 μmol·L-1 by cultivated Gracilaria lemanaiformis, and the concentration of ammonium nitrogen declined form 213.84 μmol·L-1 to zero by cultivated Enteromorpha clathrata. Other bioremediation mechanisms of seaweed inhibiting the red tide microalgae such as nutrients competition and allelopathic effects were also discussed. 相似文献
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大型海藻生境的生态功能及其在海洋牧场应用中的探讨 总被引:2,自引:2,他引:2
大型海藻是近岸海洋生态系统生态过程的重要驱动者之一,由大型海藻所形成的海藻场栖息地在维持海洋生物摄食、生长和繁殖等生命活动中扮演着极为重要的角色。然而,近年来受环境变化和人类活动等因素的影响,全球范围内许多沿海国家都出现了海藻场快速退化的现象,且对以海藻场为关键栖息地的海洋生物造成了不可忽略的影响,这一状况在我国尤为严重。为保障海洋生物资源可持续利用,海藻场修复已成为我国近岸海域生态环境保护的重要工作之一。但由于对海藻及其构造生境的生态功能认识不足,有关海藻场修复的目标定位、实现路径等存在较大的盲目性。本文从海藻场修复的角度出发,先分别对海藻及其构造生境的生态功能进行了阐述,而后对海藻养殖区是否可替代天然藻场被纳入到海洋牧场的建设中以及海藻生境生态功能的量化测定提出了几点思考,以期为今后海藻场修复工作合理、高效地开展和海藻养殖产业的可持续发展提供参考。 相似文献
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凤眼莲对污染水环境的生态修复作用 总被引:2,自引:0,他引:2
凤眼莲是重要的污染水体修复水生植物.在修复污染水体过程中根际微生物等植物修复功能性微生物发挥了重要作用。本文介绍了植物修复功能性微生物在凤眼莲生态修复中的作用并展望了凤眼莲的应用前景。指出.植物修复功能性微生物是凤眼莲进行有效生态修复的重要组成部分.进一步加强植物修复功能性策生物研究是今后凤眼莲生态修复工作取得进展的重要因素;对凤眼莲进行生物调控是解决凤眼莲生物入侵这一不利因素的有效途径;凤眼莲的克藻作用在富营养化水域生态修复中将发挥越来越重要的作用。 相似文献
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Seven species of cultivated and edible seaweeds found in Southern Taiwan—including Enteromorpha intestinalis, Monostorma nitidum, Ulva lactuca, Dictyopteris undulata, Sargassum hemiphyllum var. chinense, Laurencia intermedia, and Porphyra dentate—were used to determine their antioxidant activity by different extraction methods. All seaweeds were extracted using water at 90°C, sterilization at 121°C, homogenization, or enzymatic hydrolysis. Extracts were evaluated for their free radical-scavenging capacity using 1,1-diphenyl-2-pricrylhydrazyl (DPPH), their reducing power, and their superoxide anion scavenging activity. The DPPH-scavenging capacity of S. hemiphyllum var. chinense extracts produced by sterilization (98.59%), homogenization (94.72%), and carbohydrate-degrading enzyme treatment was higher than that of protease extracts, except for U. lactuca. The reducing power of S. hemiphyllum var. chinense water extracts and M. nitidum Viscozyme extracts was better than that of a commercial antioxidant. S. hemiphyllum var. chinense exhibited higher superoxide anion scavenging activity than the other species. The results demonstrate that different extracts of some of the seaweeds showed remarkable antioxidant activity in different assays. The results also provide important information for the marine food industry and suggest that seaweed might be a valuable source of natural antioxidants. 相似文献
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沿海地区渔业现代化水平评价指标体系研究 总被引:1,自引:0,他引:1
渔业现代化是农业现代化建设的重要组成部分,是构建和谐社会、推进新农(渔)村建设的关键环节。文章在借鉴国内外学者相关研究的基础上,构建了包括8项主体指标及29项群体指标的渔业现代化水平评价指标体系,以期为客观地评价我国沿海地区渔业现代化的发展现状,进而制订可行的现代渔业发展战略提供参考。 相似文献
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2012年夏季在爱莲湾,对采用碳酸氢铵防除养殖龙须菜(Gracilaria lemaneaformis)上的污损生物多棘麦秆虫(Caprella acanthogaster)的效果进行了研究,探讨了碳酸氢铵浓度及处理时间对多棘麦秆虫脱落率和死亡率的影响。实验的3个处理时间分别为5、10、15 min,碳酸氢铵浓度分别为0.5、0.6、0.7、0.8、0.9、1.0、2.0、3.0、4.0、5.0 g/L。结果表明,碳酸氢铵浓度、处理时间对多棘麦杆虫脱落率或死亡率均有显著影响(P0.05)。随着浓度的升高、处理时间的延长,多棘麦杆虫脱落率及死亡率都呈逐渐增加的趋势。多棘麦杆虫脱落率(D)或死亡率(M)与浓度(C)之间的关系均符合S型曲线模型lnD=a+(b/C)或lnM=c+(d/C)。在5、10、15 min时,碳酸氢铵对麦杆虫的致死浓度分别为7.36、6.17、3.68 g/L,对应的非离子氨浓度分别为37.72、21.32、14.25 mg/L。 相似文献
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冬、春季黄海南部沿岸水域浮游动物 总被引:3,自引:0,他引:3
采用2005年1月和4月在31°54′~32°06′N、121°42′~121°57′E海域2个航次的调查资料,运用定量、定性方法,分析了浮游动物季节变化,优势种对总丰度的贡献等生态学特征。结果表明:该区浮游动物以桡足类为主,冬春两季分别占总种数的92.79%和93.40%。两季各有优势种5种,其中真刺唇角水蚤(Labidocera euchaeta)和双毛纺锤水蚤(Acartia bifilosa)是冬、春季共有的优势种,优势度分别高达0.82、0.19和0.03、0.32。冬季真刺唇角水蚤对总丰度的贡献率最高,β达0.75,春季小拟哲水蚤(Paracalanus parvus)对总丰度的贡献率最高,β为0.32。春季涨落潮的多样性明显高于冬季。优势种丰度的变化是决定涨落潮总生物量变化的主要因素。 相似文献
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2014年8月(夏季)和10月(秋季)对辽宁省黄海北部沿岸海域进行了2个航次的浮游生物调查,共检测出浮游动物35种,其中夏季30种,秋季34种。浮游动物以小型桡足类和浮游幼虫为主。洪氏纺锤水蚤、短角长腹剑水蚤、小拟哲水蚤、近缘大眼剑水蚤、强壮箭虫、异体柱囊虫和双壳类幼体为夏季优势种;洪氏纺锤水蚤、短角长腹剑水蚤、近缘大眼剑水蚤、强壮箭虫、异体柱囊虫、桡足类幼虫、沃氏纺锤水蚤为秋季优势种。夏季浮游动物生物量高于秋季,生物量则低于秋季。季节变化会影响浮游动物的丰度和生物量。辽宁省黄海北部沿岸浮游动物丰度、生物量较高,小型桡足类在黄海北部沿岸浮游动物群落结构中具有重要的作用。 相似文献
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闽南沿海牡蛎、花蛤、缢蛏体内重金属的检测与评价 总被引:3,自引:1,他引:3
本文利用1998-1999年福建闽南沿海养殖贝类体的重金属检测资料,分析了3种主要养殖贝类体的重金属含量及分布。结果表明:厦门杏林宝珠屿、马銮湾海域养殖的褶牡蛎体内的重金属含量明显高于其他养殖区。不同养殖区之间养殖贝类的Cu、Pb、Cd、Zn、Hg含量,以及这些元素在各种贝类中都存在较大的差异。文中还根据全国海岸带污染综合调查专业组制定的海洋生物污染评价标准,对养殖贝类的重金属污染程度进行了评价,结果闽南沿海的养殖贝类基本未受重金属污染或污染程度较轻。 相似文献