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面对海水养殖业受挫的局面,如何安排好1995年的海水养殖生产,是摆在天津市海水养殖业面前主要的研究课题。结合天津市实际,作者提出了海水养殖业在调整中恢复的基本思路。 相似文献
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简述了我国常见的4种外来鲑形目物种大西洋鲑、虹鳟、金鳟和美洲红点鲑形态特征、生物习性、分布和养殖概况、扩散风险及防控建议等，对其形态差异性进行了对比。指出，外来水生生物在自然水域的繁衍和种群扩张会对本土原生物种、种群结构、群落结构及食物链产生系列连锁影响，威胁本土水域生态系统的安全和稳定。提出，应进一步健全外来物种海关监管机制，建立外来物种引种评估规范，制定外来水生生物放生、弃养处理办法，深化国际合作，建立跨界水域生态系统保护协作机制。最终实现合理利用外来物种、保护国门生物安全、国内生态和种质资源安全的目标。 相似文献
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中国水生外来物种入侵现状和对策 总被引：6，自引：0，他引：6
水生外来物种入侵是指某物种在某水域生态系统中原来没有,通过人为有意或无意活动从其它生态系统中引入,一旦该物种在当地形成自己繁殖,并对当地生态或者经济造成破坏,该物种就构成了水生外来物政策导航责任编辑肖乐种入侵。入侵种可能是水生植物或者动物,也可能是一种病毒或细菌。水生外来物种一旦入侵成功,将对当地水生物种的种类、种群结构、食物链结构、生物多样性等产生一系列的影响,威胁渔业生产、经济和生态安全。我国水生外来物种入侵现状我国水生外来物种入侵的总体状况近20年来,随着水产养殖、水簇产业的发展以及资源增殖放流的需… 相似文献
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水产养殖池塘对水域生态环境的影响 总被引：1，自引：0，他引：1
本文根据全国部分地区海水养殖池塘水质检测结果、天津市部分郊县养鱼池、水库、河道总氨、总磷、化学耗氧量检测结果,对照城镇污水处理厂部分污染物排放标准进行分析、对比,对海、淡水养殖池塘对环境的污染做了全面的综述,探讨了海水、淡水养殖池塘自身的污染类型对环境的影响指标,并提出防治关键性污染指标的对策及建议。 相似文献
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Maxine P. Piggott Samuel C. Banks Ben T. Broadhurst Christopher J. Fulton Mark Lintermans 《水产资源保护:海洋与淡水生态系统》2021,31(1):173-184
- Detecting rare species is often a necessity for conservation and management, yet challenging for many field survey methods. Environmental DNA (eDNA) is a highly promising solution that has been shown to outperform many established survey methods.
- Macquarie perch (Macquaria australasica) is an endangered native species that has declined significantly in range and abundance. Detection of M. australasica was compared with an abundant alien fish species (Oncorhynchus mykiss) using eDNA and three conventional survey methods: gill nets, electrofishing and fyke nets.
- eDNA occupancy estimates for both fish species were compared using four different models to investigate what effect these differences have on false positives and false negatives for the rare and common fish species. These models used unadjusted eDNA detections in water samples, eDNA detections that have been screened using a limit of detection method to remove potential false positives, eDNA data supplemented with a second survey method, or eDNA data augmented with sequencing of positive polymerase chain reaction replicates.
- eDNA surveying as a single detection method was found to be more efficient and sensitive compared with each capture method separately and combined. Occupancy estimates for the common and rare species did not vary significantly between the four site occupancy-detection models, suggesting that supplementary data may not have as much effect on occupancy estimates compared with other approaches such as temporal or spatial sampling.
- We conclude that eDNA outperforms the three established survey methods for both a rare and common freshwater fish species. Although there was no significant effect of augmenting eDNA survey methods with other survey data, additional data may improve confidence in detection, and provide confirmatory evidence for unexpected or new detections of a species.
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Francisca C. Aguiar M. Teresa Ferreira António Albuquerque Ilídio Moreira 《水产资源保护:海洋与淡水生态系统》2007,17(4):335-347
- 1. A comparison was made between a variety of alien and endemic plant species from 272 aquatic and riparian habitats in Portuguese Mediterranean‐type streams in reference condition — i.e. near‐natural river corridors — and non‐reference condition. The objective was to detect differences in relative proportion and cover between these species groups. The differences in endemic and alien flora from siliceous and calcareous river types were also analysed. Environmental and human disturbance factors were related with the richness and cover of both species groups.
- 2. A total of 568 species were found, of which 44 were alien and 28 were endemic. Alien species were present at 91% of the surveyed locations, and were consistently more widespread at non‐reference sites than at reference ones for both river types, with calcareous sites having a higher invasibility. Endemic species occurred at 45% of the sampling sites and displayed a significantly lower richness and cover than their alien counterparts.
- 3. Alien richness and cover were positively related to direct human disturbance within the river systems, and with floodplain uses such as urban occupation, intensive agriculture, and nutrient inputs. Endemic species also respond to anthropogenic variables, rather than to climatic and geographical ones, with richness and cover increasing as human impacts on fluvial systems and related floodplains decrease.
- 4. Comprehensive control of alien invasive species and the protection of endemic plant populations will require attempts at monitoring ecological river integrity, and the achievement of ‘good ecological status’ — one of the goals of the European Union's Water Framework Directive. Portuguese riparian areas must be managed in such a way as to protect the relatively few preserved riparian habitats by lowering the direct and indirect pressures in fluvial corridors and thus preventing future alien plant invasions.
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中国深远海养殖发展方式研究 总被引：1，自引：0，他引：1
在渔业转型发展进程中,发展深远海养殖是突破生态环境和自然资源约束性挑战,实现新时期中国海水养殖业可持续发展的战略方向。基于联合国粮食及农业组织(FAO)关于深远海养殖发展的定义,结合中国海水养殖业发展水平和海域条件,对中国深远海养殖概念进行了界定。提出养殖品种选择、养殖系统构建、养殖海域规划是关系深远海养殖产业稳步有序发展的重要因素。在养殖品种选择方面,应重点考虑经济潜力、适应水温和养殖技术;在养殖系统构建上,分析比较了不同养殖系统应用于深远海养殖的适宜性、安全性和经济性;在养殖海域规划方面,应重点考虑养殖排放、环境承载力和海域条件。 相似文献
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Biological and technical evaluation of the potential of marine and anadromous fish species for cold-water mariculture 总被引：4，自引：1，他引：4
Concern about the overexploitation of wild aquatic resources, the slow recovery of the groundfish fisheries and the need to encourage the diversification of the mariculture industry of the province of Quebec (Canada) all provided strong incentive to explore the potential of a wide selection of marine and anadromous fish species for cold‐water mariculture. Starting from a list of over 45 indigenous fish species of potential commercial interest, a biotechnical review was initiated. Technical sheets for each species were produced and aquaculture‐based selection criteria covering three aquaculture approaches of development (complete life cycle, on‐growing and stock enhancement) were examined. Species were ranked according to their degree of suitability for the given biological parameters. The final classification analysis within the complete life cycle production strategy positioned the Atlantic wolffish as the top candidate species (91%) followed by the spotted wolffish and Arctic charr (87%). Growth rate, optimal growth temperature, duration of the weaning period, minimal lethal temperature, larval size and feed requirements were the determining criteria. The on‐growing scenario final results ranked Arctic charr first (84%) followed by Atlantic cod (79%) and Atlantic halibut (74%) mostly owing to their growth rate at low temperature and optimal growth temperature criteria. Stock enhancement programmes should concentrate their efforts on the striped bass (56%), the haddock (54%) and the Atlantic sturgeon (34%) based on their growth rate, fishery status, landing price and the availability of impact studies. 相似文献
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Ecological traits of fish assemblages from Mediterranean Europe and their responses to human disturbance 总被引：2，自引：1，他引：1
T. FERREIRA & J. OLIVEIRA N. CAIOLA & A. DE SOSTOA F. CASALS R. CORTES A. ECONOMOU & S. ZOGARIS D. GARCIA-JALON M. ILHÉU F. MARTINEZ-CAPEL D. PONT & C. ROGERS J. PRENDA 《Fisheries Management and Ecology》2007,14(6):473-481
Abstract Mediterranean river systems are characterised by more diverse fish assemblages and regional ecological processes compared with the rest of Europe. A data set from Mediterranean France, Iberia and Greece (∼2000 sites) was used to describe the characteristics of fish assemblages, explore their responses to anthropogenic disturbance and analyse the implications for river quality assessment. There was a southwards decline in species richness per site, but endemicity and proportion of alien species increased. Sites in the eastern Mediterranean had higher endemicity, lower site richness and lower number of alien species than sites in western Mediterranean Europe. Assemblage composition differed between Mediterranean sub-regions, but was dominated by three major fish types: a salmonid fish type common throughout the study area and two cyprinid-dominated fish types (in some sub-regions, Salmo trutta L. is present but not numerically dominant), corresponding to a gradient in hydrological and temperature regimes. Metric responses to perturbation were compared with those found at the European (larger scale) and basin (smaller scale) levels. Overall metric response was weaker in this Mediterranean application. The best responses to human pressure were usually obtained with abundance-based metrics and included the contribution of naturalised alien species. Some widespread alien species contributed to the response to anthropogenic alteration (notably Cyprinus carpio L. and Lepomis gibbosus (L.)). 相似文献
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Sena S De Silva Thuy T T Nguyen Nigel W Abery Upali S Amarasinghe 《Aquaculture Research》2006,37(1):1-17
Asia dominates global aquaculture production accounting for over 80% of the total and the mainstay in Asian aquaculture is finfish. Over the years, Asia has experienced a number of inter‐continental and intra‐continental transfers/introductions/translocation of finfish species, between nations and watersheds, beyond their natural range of distribution, primarily for aquaculture development. In this article all such species are referred to as alien species. An attempt is made to evaluate the importance of the production of alien species in selected Asian nations, using statistics of the Food and Agriculture Organization. Also, negative effects, if any, based on literature surveys, of alien species in relation to displacement of indigenous species, and on biodiversity and/or genetic diversity together with associated pathogen transfers are evaluated. The major alien species, based on their significance to Asian inland aquaculture considered, are the tilapias, catfish, Chinese and Indian major carps and common carp. It is estimated that currently alien species account for nearly 12% of the cultured finfish production (2.6 million tonnes) in Asia, valued at US$ 2.59 billion, and the contribution exceeds 40% when Asian countries excluding China are taken into consideration. Inland finfish aquaculture in some Asian nations, such as Indonesia and the Philippines, is predominated by alien species, and in some others, e.g. Bangladesh and India, the contribution from alien species has been increasing steadily. It is suggested that overall alien finfish species have done little ecological harm to native flora and fauna. However, in the wake of increasing anthropogenic development taking place in watersheds the resulting environments are often made unconducive to indigenous species but not to some alien species, thereby potentially and indirectly making the latter invasive. 相似文献
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Weak effects of habitat type on susceptibility to invasive freshwater species: an Italian case study 
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下载免费PDF全文 Angela Boggero Alberto Basset Martina Austoni Enrico Barbone Luca Bartolozzi Isabella Bertani Alessandro Campanaro Antonella Cattaneo Fabio Cianferoni Giuseppe Corriero Ambrosius Martin Dörr A. Concetta Elia Gentile Francesco Ficetola Lyudmila Kamburska Gianandrea La Porta Sara Lauceri Alessandro Ludovisi Elda Gaino Enzo Goretti Massimo Lorenzoni Marina Manca Aldo Marchetto Giuseppe Morabito Francesco Nonnis Marzano Alessandro Oggioni Cataldo Pierri Nicoletta Riccardi Giampaolo Rossetti Nicola Ungaro Pietro Volta Silvia Zaupa Diego Fontaneto 《水产资源保护:海洋与淡水生态系统》2014,24(6):841-852
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中国水产养殖种类组成、不投饵率和营养级 总被引：6，自引：1，他引：5
根据1950–2014年水产养殖种(类)有关统计和调研数据,并在对养殖投饵率、饲料中鱼粉鱼油比例、各类饵料(配合饲料、鲜杂鱼/低值贝类/活鱼、天然饵料等)营养级等基本参数进行估算的基础上,研究分析了中国水产养殖种类组成、生物多样性、不投饵率和营养级的特点及其变化。结果表明:中国水产养殖结构相对稳定,变化较小,其显著特点是种类多样性丰富、优势种显著、营养层次多、营养级低、生态效率高、生物量产出多。其中:(1)养殖种类296个、品种143个,合计为439个。种类组成区域差异明显,淡水养殖鱼类占绝对优势,如2014年草鱼、鲢鱼、鳙鱼、鲤鱼、鲫鱼和罗非鱼排名前6个种类的养殖占淡水养殖产量69.6%,其次为甲壳类、其他类、贝类及藻类,而海水养殖则以贝藻类为主,如2014年牡蛎、蛤、扇贝、海带、贻贝和蛏6个种(类)的养殖占海水养殖产量71.3%,其次为甲壳类、鱼类及其他类;(2)养殖种类多样性特征显著,与世界其他主要水产养殖国家相比,独为一支,具较高的多样性、丰富度和均匀度,发展态势良好;(3)由于养殖方式从天然养殖向投饵养殖转变,不投饵率呈明显下降趋势,从1995年90.5%降至2014年53.8%(淡水35.7%,海水83.0%),但与世界平均水平相比,仍保持较高的水准;(4)与世界相比,营养级低且较稳定。由于配合饲料的广泛使用及其鱼粉鱼油使用量减少,近年营养级略有下降,从2005年较高的2.32降至2014年2.25(淡水2.35,海水2.10)。营养级金字塔由4级构成,以营养级2为主,近年占70%,表明其生态系统有较多的生物量产出。中国水产养殖未来发展需要遵循绿色、可持续和环境友好的发展理念,探讨适宜的、特点各异的新生产模式,发展以养殖容量为基础的生态系统水平的水产养殖管理,建设环境友好型的水产养殖业,为保障国家食物安全、促进生态文明建设作出更大贡献。 相似文献
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海水养殖业合理的结构与良好的发展趋势有利于促进福建省经济的长远发展。本文基于福建省1983—2012年的海产品产量与海水养殖产量数据,研究了福建省鱼类、虾蟹类、贝类、藻类等海产品和海水养殖产品的产量结构特征,结果表明福建省海水养殖主要以贝类、藻类为主,海洋捕捞主要以鱼类、虾蟹类为主;分析了福建省海水养殖的养殖比、面积、单产等的发展趋势,得出鱼类、虾蟹类增加趋势较大,增产潜力大;针对福建省海水养殖产量结构特征和发展趋势,进行成因分析并提出对策。研究结果可以为渔业部门指导福建省海水养殖业的发展提供参考。 相似文献