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1.
Coastal Fish Diversity in Three Marine Protected Areas and One Unprotected Area in the Gulf of Trieste (Northern Adriatic) 总被引:1,自引:0,他引:1
Abstract. The coastal fish assemblage in three protected sites and one unprotected area in the Slovenian part of the Gulf of Trieste (Northern Adriatic) was studied. Species composition and richness were comparable at all studied sites, including the control, unprotected area. Differences in fish density between the protected area of Debeli rti? and the unprotected area of Fiesa‐Pacug were revealed using correspondence analysis. Particularly the densities of certain labrid species (Symphodus cinereus and S. roissali) were higher in the protected area. Those differences are attributable to the extended and densely vegetated infralittoral belt of the Debeli rti? area rather than to its protected status. 相似文献
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The blue mussels Mytilus edulis and Mytilus trossulus occur sympatrically and are able to hybridize in populations on the eastern coast of Newfoundland, Canada, presenting an opportunity to study their aggregational behavior. Aggregation behavior may therefore provide insight into post‐settlement interactions and pre‐zygotic reproductive isolation between the species. Three treatments were designed using M. edulis and M. trossulus to investigate their intraspecific and interspecific spatial distribution patterns. With Ripley’s K‐function and Monte Carlo simulation analysis, we found that in the single‐species treatment, M. edulis aggregated significantly but not M. trossulus. Based on results of two‐way ANOVAs, both the number of aggregations and the moving distance were significantly affected by the treatments (single‐species or mixed‐species treatment) and times (24, 48, 72 and 96 h). In further pairwise comparisons using Tukey’s test, M. edulis aggregated differently with or without M. trossulus occupying the same tank, suggesting that the aggregational behavior of M. edulis could be driven by species‐specific chemical cues. The result that M. edulis aggregates intraspecifically may increase the probability of intraspecific fertilization of the spawned gametes and thus function as a pre‐zygotic reproductive isolation mechanism maintaining the blue mussel hybrid zone. 相似文献
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Abstract. Zooplankton is an essential component of the marine and brackish food chains. The ecotoxicological risk of zooplanktonic communities, estimated by the modern methodological approach of biomarkers, can be used as an early warning signal of ecosystem health. The aim of this project is to estimate the potential use of several biomarkers (esterases, mixed function oxidases, porphyrins) in zooplanktonic organisms. Studies were carried out with different zooplanktonic crustaceans: the copepods Acartia margalefi and Acartia latisetosa collected in Ganzirri Lake (Messina); the mysid Siriella clausi collected in Faro Lake (Messina); the mysids Diamysis bahirensis, Siriella armata and Mysidopsis gibbosa collected in Stagnone di Marsala (Palermo); the Antarctic euphausiids Euphausia crystallorophias and Euphausia superba; the am-phipod Streetsia challengeri and the euphausiid Meganycthiphanes norvegica collected after a shore-stranding along Messina's Ionian coast. Moreover, experiments were carried out with the benthic decapods Eriphia verrucosa and Pachygrapsus marmoratus from a rocky shore of Messina's Ionian coast. Acetylcholinesterase activity (AChE) was determined in homogenates of whole organisms. The key result of this project concerns the different AChE activity basal values of different crustacean species. Particular attention should be paid to the difference in basal activity found between the Antarctic and the Mediterranean species. 相似文献
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The Mediterranean mussel Mytilus galloprovincialis is the most significant invasive alien marine species in South Africa and, although not normally found subtidally, has recently been observed colonising heads and stipes of the kelp species Ecklonia maxima in False Bay. We quantified this invasion and explored its ecological implications. Transects laid across kelp beds revealed that 10.34% of kelp individuals surveyed bore canopy mussels, with kelp heads (10.07%) being far more commonly infected than stipes (0.27%). Twenty kelp individuals with infected heads and 20 with infected stipes were separately collected for more-detailed examination. Wet mass of mussels on these kelp heads ranged from 2.5 to 2 462 g (median 86.4 g, interquartile range 14.8–353.8 g) and that of mussels on the stipes from 7.6 to 3 492 g (median 595.5 g, interquartile range 194.0–955.0 g). Mussel clumps consisted mostly of individuals <40 mm in length. Mussel clumps supported a rich biota of 80 invertebrate and 13 algal species. Larger clumps supported more epibiotic species, and those on stipes more species than those of comparable mass on kelp heads. The mussels and their associated epibiotic species negatively affected kelp buoyancy, but rarely enough to overcome natural buoyancy. Some kelp individuals that had been toppled by the weight of mussels and their epibiotic species, however, were encountered in situ. Implications of this invasion include large increases in animal biomass and species richness in the kelp canopy, plus reductions in kelp buoyancy and increased hydrodynamic drag on infected kelps, increasing their probability of being uprooted. Uprooted kelp individuals can raft long distances, potentially transporting both native and alien species to distant sites. 相似文献
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近海污染物总量控制水质监测体系构建方法——以莱州湾为例 总被引:1,自引:0,他引:1
《中国海洋大学学报(自然科学版)》2015,(11)
水质监测是总量控制实施的重要环节,当前水质监测体系已不能满足总量控制效果评估的需求。为此,本文建立了近海污染物总量控制水质监测站位布设的聚类抽点检验方法,主要分为源强海域水质响应分析、陆海混合区分析、水质浓度分布聚类分析、初始站位设置、抽点检验分析等5个步骤,并给出了监测项目和频次的建议。以莱州湾为例进行了评价,结果表明,利用本文方法得到的2套优化监测站位,不仅可以对排污口进行有效监控,而且水质平面分布可以准确表征水质分布规律,无论是模拟结果还是监测结果,相似度和相关性均超过90%(P0.01),相对标准偏差均小于10%,本文所建方法有助于中国近海污染物总量控制环境监测体系的建设。 相似文献
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A number of biochemical markers and a physiological index were measured in mussels, Mytilus galloprovincialis, transplanted or native to five different contaminated sites in the lagoon of Venice. Mussels from Pellestrina, a reference site in the adjacent Adriatic Sea, were transplanted for 6 weeks to areas of the lagoon where indigenous mussels were also collected. As biochemical indices, superoxide dismutase (SOD), catalase, aldehyde dehydrogenase (ADH) and NADPH cytochrome c reductase (NADPHcred) were measured in mussel digestive gland; survival in air as a physiological index was also determined. Biomarker responses varied among sites and between indigenous and transplanted animals. Significant induction of catalase and SOD was shown in animals transplanted to the urban sites of Salute and Chioggia, respectively. In indigenous mussels, induction of SOD and NADPHcred was seen in animals from the polluted site of Treporti and the heavily contaminated industrial area of Marghera. The overall biochemical data indicate significantly higher activity for ADH in transplanted animals in comparison with indigenous ones which, in contrast, present an increase in SOD. As regard survival in air, control mussels did not seem to be healthier in comparison either with transplanted or indigenous ones, suggesting that pollution has no effect on this parameter. 相似文献
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粤港澳大湾区作为国家战略,在“推进生态文明建设”方面明确提出了要“打造生态防护屏障”。东莞市滨海湾新区位于大湾区珠江口东岸,是大湾区几何中心和珠江口城市群连接点,规划为未来新城中心,其河口海岸生态修复具有典型意义。文章通过文献综述、资料梳理和规划分析等方法,从东莞滨海湾新区河口海岸自然环境现状出发,在分析其生态环境存在的问题的基础上,提出滨海湾新区应以河口海岸自然环境特征为基础,在保障河口行洪纳潮安全的前提下,对接海陆功能,开展沿海岸线的生态修复工程,打造东莞滨海湾新区“一堤一港一岛一廊多园”的生态海岸带,建设珠江河口“美丽湾区”。建议粤港澳大湾区河口海岸开展生态修复应以安全性为第一要素,因地制宜实施精细化修复,探索岸线异地修复制度,实现以“生态空间”支撑“发展空间”。 相似文献
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文章以生态系统健康评价(EHA)为工具,利用2004-2013年以来闽东沿岸生态监控区的监测数据及相关文献资料,对闽东沿岸生态监控区的海洋生态健康状况进行分析评价,分析影响闽东沿岸生态监控区海洋生态健康的主要因子。结果表明:闽东沿岸生态监控区生态环境健康状况基本处亚健康状态,但有进一步恶化的风险,水环境中pH值、氮-磷营养盐含量呈明显上升的趋势;生物质量受到不同程度的污染,贝类体内铅含量显著上升;生物环境处于不健康状态,生物种类数呈减少的趋势。结合闽东沿岸生态监控区存在的问题提出:(1)加强污染物入海总量控制制度,推行节能减排措施;(2)加强生物质量控制,发展蓝色海洋经济;(3)休渔、生态补偿制度相结合,有效利用和保护海洋资源;(4)严格控制围填海工程,保护滩涂湿地;(5)加强海洋环境监测体系建设等建议。 相似文献
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香港近岸海域营养盐结构特征及其对浮游植物生长的影响 总被引:4,自引:1,他引:4
本文利用2000年3月至2001年5月在香港近岸牛尾海海域(Porter Shelter, Hong Kong)14个航次的现场调查数据, 对水体中营养盐组成结构和叶绿素a含量进行了分析研究。结果表明, 该海域表层和底层水体中溶解无机氮(DIN, 包括NO3?-N+NO2?-N, NH4+-N)平均浓度范围分别为1.24—9.72mol/L及1.30—7.49mol/L, 均表现为冬季最高、秋季最低。不同季节表层水体中PO43?-P浓度范围为0.14—0.46mol/L, 夏季平均浓度最底; 底层 PO43?-P浓度变化不大, 但夏季仍低于其他季节。不同季节表层和底层水体中SiO32?-Si的变化趋势基本相似, 平均浓度范围分别为7.80—18.47mol/L 和8.13—16.87mol/L, 均在冬季最高, 其它季节差别不大。叶绿素 a分析结果显示, 表层水体高生物量大多出现在夏末秋初季节(如8月份), 春季(4月份)次之; 底层水体叶绿素 a秋季最高, 夏季次之。进一步分析了该海域营养盐对浮游植物生长的可能限制因子, 结果表明表层水体春季呈现氮–磷协同限制的可能性、夏季磷限制较明显, 秋季表现为显著的氮限制。底层水体春、夏季呈现氮–磷协同限制的趋势, 秋季也表现为明显的氮限制。冬季磷酸盐浓度相对氮、硅的含量较低, 但各种营养盐相对于浮游植物生长的最低阈值都比较丰富, 所以, 冬季表、底层水体中营养盐对浮游植物的生长均不形成限制因素。另外, 除了夏季表层水体外, 其它季节该水域浮游植物生长受溶解无机硅限制的可能性较少。 相似文献
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Faecal coliform levels were determined for sea water and shellfish flesh from farms of the green mussel, Perna canaliculus, in Pelorus Sound, Marlborough Sounds, New Zealand. Simple linear models were developed to relate logarithmically transformed data on the faecal coliform levels to measures of fresh water entering the mussel beds. These models support guidelines to restrict harvesting following periods of heavy rain in order to comply with shellfish sanitation standards. Alternative guidelines are suggested based on the volume of river water entering the sound or salinity. 相似文献
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运用经典统计学和地统计学的方法研究了莱州湾南岸地区不同土地利用和土地覆被下土壤盐分含量的特征及分布情况。研究结果表明:不同空间位置不同层位的土壤盐分含量差异性较大;土壤盐分含量表现出盐田>棉花>林地>杂草>大豆>玉米的现象;除林地60~90 cm土壤盐分变异系数具有强变异外,其它各层土壤盐分含量均具有中等变异性;表层土壤盐分含量具有中等空间自相关性,其它土层土壤盐分含量具有强的空间自相关性;研究区各层土壤盐分的空间分布均表现出条带状和斑块状格局,以轻盐渍化和中度盐渍化为主。 相似文献
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As worldwide population continues to grow, so does demand for seafood by consumers. With this trend, interest in sustainably certified seafood is also increasing. The Maine lobster fishery is currently considering certification based on the Marine Stewardship Council (MSC) standard for sustainable and well-managed fisheries. Although certification is argued to provide a market-based incentive to improve sustainable fishing practices, it is a costly and time-consuming process, and often imposes additional requirements on fisheries in order to meet certification standards. To evaluate whether the costs of Maine lobster fishery certification are worth the presumed benefits, lobster industry members were interviewed to learn their opinions of MSC certification, seafood consumers were surveyed to understand their attitudes and purchasing preferences related to lobster, and lessons learned from other MSC-certified fisheries were compiled. MSC certification of the Maine lobster fishery could potentially provide benefits to the industry by differentiating Maine lobster and maintaining access to markets that are looking to exclusively source certified fish products. However, certification is unlikely to provide price premiums for the fishermen, and does not necessarily represent to consumers the most desirable aspects of Maine lobster. Certification programs may need to adapt to consumer preferences and market conditions if they are to continue to provide incentives for the sustainable management of fisheries. 相似文献
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The European Atlas of the Seas is a web-based information system aimed at the general public, but it is also capable of supporting selected nonspecialist professionals in addressing environmental issues, human activities, and policies related to the coast and sea. It includes a collection of maps and associated fact sheets based on data originating primarily from the European Commission and its agencies, which present a snapshot of key natural and socio-economic elements of the coastal and marine regions of the European Union. It provides a suite of basic instruments for map analysis and data combination to derive ad hoc maritime indicators. 相似文献
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The basic approaches, methods, and procedures for collecting and analyzing samples of microplastics in a marine environment are briefly described. 相似文献
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文章结合连江海洋减灾综合示范区的总体建设情况,重点分析海洋灾害监控防控系统的构建思路和成果应用,主要包括海洋在线监测系统、海洋灾害信息发布系统、海洋减灾综合应急标志系统和海洋减灾综合视频监控系统,为其他地区开展以沿海重点养殖区为重点保障目标的海洋减灾综合示范区建设提供借鉴和参考。 相似文献
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Limiting accessibility to a fishing area can reduce fishing effort effectively and may therefore promote local recovery of depleted stocks. In January 2002, beach driving was banned in South Africa, thereby reducing angler access to large areas of the coastline, particularly in less-developed areas. In November 2001 a project had been established in the St Lucia Marine Reserve, on the east coast of South Africa, to compare surf-zone fish populations inside a no-take sanctuary zone with those in an adjacent exploited area. Subsequent to the ban, the aim of the project was adapted such that surf-zone fish populations were monitored for potential recovery in what had been the exploited area, located to the north of Cape Vidal, which anglers could no longer access easily, because of the prohibition on beach driving. Standardised research fishing was conducted at two sites in the previously exploited area and two sites in the no-take sanctuary. Conventional stock-status indicators showed evidence of recovery in the four most common species caught in the previously exploited area, in terms of both abundance and biomass. Generalised additive mixed models were used to account for the influence of targeting specific species; however, subtle differences in habitat between the sampling sites, improved angling skill over time, variability in recruitment, and differential species-specific responses complicated interpretation of results. The implications of the findings are discussed in terms of the future monitoring and management of marine protected areas both within the St Lucia Marine Reserve and farther afield. 相似文献