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1.
象山港不同生境冬季浮游动物生态特征比较研究   总被引:4,自引:0,他引:4  
2010年1月底,对象山港西部海区的海带养殖区、牡蛎养殖区、网箱养殖区、增殖放流区和电厂温排水区进行了浮游动物调查,从生物量、丰度和多样性指数这3个参数比较了5种不同生境的浮游动物特征,并对这3个参数与理化因子进行相关性分析.结果显示:从5种生境中共鉴定到浮游动物28种,以桡足类的腹针胸刺水蚤(Centropages abdominalis)为绝对优势种;浮游动物整体的生物量大,丰度高,而多样性指数低.5种牛境比较,浮游动物的生物量为牡蛎养殖区最高,网箱养殖区和海带养殖区次之,增殖放流区和温排水区最低;丰度为牡蛎养殖区最高,网箱养殖区次之,再其次是海带养殖区,增殖放流区和温排水区最低;对3类养殖区内外的浮游动物的生物量和丰度进行比较,均为养殖区内较高;浮游动物的多样性指数为温排水区最高,其他4种生境差异不明显.相关性分析表明:浮游动物的生物量与悬浮物的浓度呈显著负相关;丰度与盐度呈显著负相关;多样性与温度、盐度和5项营养盐有显著相关性.  相似文献   

2.
选择象山港海域人工鱼礁、海带(Laminaria japonica)与熊本牡蛎(Crassostrea sikamea)浮筏式养殖区等为研究区域, 通过分析其与对照区浮游动物群落及栖息环境差异, 探究典型海洋牧场营造设施对浮游动物群落的影响方式。结果表明, 人工鱼礁、海带与熊本牡蛎浮筏式养殖区和对照区浮游动物群落结构差异显著, 不同海洋牧场营造设施对浮游动物群落的影响方式各异。与对照区相比, 人工鱼礁区浮游动物多样性指数较低, 但总丰度较高, 优势种腹针胸刺水蚤(Centropages abdominalis)丰度为对照区的 3.28倍, 斑鰶(Konosirus punctatus)和黑棘鲷(Acanthopagrus schlegelii)等渔业资源种类的鱼卵和仔稚鱼在人工鱼礁区密集分布, 人工鱼礁显现出良好的渔业资源增殖养护功效。海带养殖区无机氮和活性磷酸盐浓度较对照区显著降低, 叶绿素 a 浓度明显增高, 浮游动物总丰度和多样性指数与对照区差异不显著, 钩虾(Gammaridae sp.)和麦秆虫(Caprellidae sp.)等端足类较为集聚, 鱼类浮游生物分布较少。熊本牡蛎养殖区无机氮和活性磷酸盐浓度高于对照区, 浮游动物总丰度较对照区有所降低, 但麦秆虫和黑棘鲷鱼卵与仔稚鱼丰度明显高于对照区。  相似文献   

3.
通过构建16S rDNA克隆文库对象山港南沙岛不同养殖模式(贝类养殖、藻类养殖及网箱养殖)表层沉积物微生物多样性和群落结构特征进行了比较和分析,共获取136个OUT。其中,贝类养殖区、藻类养殖区和网箱养殖区OTU分别为58、48和57个。各站位OTU分布差异明显,表现出高度的多样性。基于16S rDNA序列的生物多样性和丰富度分析表明,网箱养殖区丰富度指数ACE为739,香浓指数H?为3.8,均为最高值,丰富度指数Chao为245,略低于于贝类养殖区。贝类养殖区丰富度指数Chao为303,在各养殖区中最高。藻类养殖区丰富度指数ACE为174、Chao为89,香浓指数H?为3.6,均为最低值。系统发育分析表明,南沙岛各养殖区的优势种群均为变形菌门(Proteobacteria),但是藻类养殖区微生物群落结构与其他养殖区域相比,16S rDNA克隆文库差异显著,其中根瘤菌属(Rhizobium)及其他光合细菌在藻类养殖区分布较多。网箱养殖区沉积物表层微生物群落中出现了与环境污染密切相关的菌群,如志贺氏菌属(Shigella)、埃希氏菌属(Escherichia)和ε-变形菌纲的微生物种群,揭示网箱养殖对底质沉积物环境的影响较大。  相似文献   

4.
为了解流沙湾养殖活动对浮游动物群落的影响,于2015—2016年对流沙湾海区进行了夏(8月)、秋(11月)、冬(2月)、春(5月) 4个季度的浮游动物调查,分析了浮游动物群落特征及其与环境因子的相关性。共记录浮游动物18大类119种、浮游幼体17种。浮游动物种类组成以桡足类(45种)和端足类(20种)为主,其次为毛颚类(15种)、水螅水母类(12种)、等足类(6种)等。十足目幼体(Decapod larvae)为春、夏两季的主要优势类群,亚强次真哲水蚤(Subeucalanus subcrassus)、微驼隆哲水蚤(Acrocalanus gracilis)为秋季主要优势种,夜光虫(Noctiluca scintillans)为冬季主要优势种。年均浮游动物丰度和生物量分别为151. 53个·m~(-3)和73. 48 mg·m~(-3)。多维尺度分析(n MDS)结果表明,除春季外,流沙湾内湾浮游动物群落组成与外湾差异明显。典范对应分析(CCA)显示,溶解氧、磷酸盐、透明度、温度和硝酸盐等环境因子是影响浮游动物优势种分布的主要因素。在流沙湾海区,鱼类小网箱的养殖活动在夏秋两季对浮游动物群落组成和结构影响较大;贝类养殖区的浮游动物的丰度和生物量明显降低,但浮游动物群落组成及多样性与其它采样点差异不大。  相似文献   

5.
象山港养殖区与非养殖区大型底栖生物生态比较研究   总被引:19,自引:1,他引:18       下载免费PDF全文
高爱根 《水产学报》2003,27(1):25-31
2000年在象山港3个养殖区(海带、牡蛎、鱼类)和非养殖区水域进行了四季调查,对养殖区和非养殖区大型底栖生物的生态学进行比较研究。调查鉴定出71种大型底栖生物,其中养殖区45种、非养殖区61种,两区共有种为35种。牡蛎养殖区外侧、鱼类网箱养殖区周围平均生物量和密度分别高达433.53g·m-2和155ind·m-2、91.92g·m-2和114.96ind·m-2;海带养殖区仅为1.55g·m-2和27.5ind·m-2,也明显低于非养殖区5.24g·m-2和53.04ind·m-2;鱼类网箱养殖区中心未见生物分布。本文同时对底栖生物与养殖生物、沉积物及水文环境因子的相关性作了研究探讨。  相似文献   

6.
黄海北部春季和夏季浮游动物生态特性与时空分布   总被引:2,自引:0,他引:2  
根据2015年3月(春季)和6月(夏季)对黄海北部辽宁近岸海域的浮游动物调查结果,分析了两个季节的浮游动物种类、生物量、丰度等群落结构特征。此次调查共鉴定出浮游动物47种,其中春季42种,夏季34种。浮游动物以浮游幼虫和小型桡足类为主。桡足类幼虫、棘皮动物幼体、桡足类幼体、洪氏纺锤水蚤、短角长腹剑水蚤、小拟哲水蚤、拟长腹剑水蚤和腹针胸刺水蚤为春季优势种;夏季浮游动物优势种依次为桡足类幼体、洪氏纺锤水蚤,拟长腹剑水蚤、短角长腹剑水蚤、桡足类幼虫、小拟哲水蚤和腹针胸刺水蚤。春季浮游动物平均生物量为512.09mg/m~3,平均丰度为15 522.18个/m~3;夏季浮游动物平均生物量为218.84mg/m~3,平均丰度为7582.39个/m~3;浮游动物生物量和丰度均为春季较高。黄海北部辽宁沿岸海域的浮游动物生物量、丰度较高。水温是影响浮游动物群落结构的重要环境因子。  相似文献   

7.
于2012年5月–2013年1月对流沙湾海区浮游动物进行了周年性的季度调查,共检出浮游动物41种、幼体17类,以桡足类居多(29种)。亚强次真哲水蚤(Subeucalanus subcrassus)、短尾类幼虫(Brachyuran larva)、长尾幼体(Macruran larva)在四季均有出现,并在3个季度中成为优势种。年均浮游动物丰度和生物量分别为48.12 ind./m3、13.43 mg/m3。扇贝主养区、鱼类网箱养殖区和珍珠贝养殖区的各季浮游动物丰度及生物量均低于对照区(非养殖区);大中型浮游动物主要出现在对照区,而在鱼、贝养殖区极少出现。冬季扇贝主养区多样性指数为各区最高,其浮游动物丰度、生物量迅速回升,高于鱼类网箱养殖区和珍珠贝养殖区,但仍低于对照区。研究结果显示,鱼、贝养殖区域流沙湾海区的浮游动物丰度及生物量比往年明显减小,浮游动物的小型化加剧。  相似文献   

8.
大小窑湾浮筏养殖水化学环境的初步研究   总被引:1,自引:0,他引:1  
本文以1995年8 ̄9月对大小窑湾浮筏养殖水域的水环境监测数据为资料,分析得出该两个封闭海湾具有适合于浮筏养殖贝类生长的温度、PH、盐度、透明度等自然条件,有较高的溶解氧和丰富的营养盐,有较高密度的浮游植物和微小型浮游动物作为饵料基础,是理想的海水养殖区。但由于海湾地理环境特点和养殖密度大等因素的影响,湾内筏区内外排各项水化学要素含量有明显差异。在8 ̄9月高温期间,氨氮含量构成可溶性无机氮的主要部  相似文献   

9.
通过对千岛湖网箱养殖区内外水域的四季水质调查,分析得出网箱养殖对千岛湖局部水域会产生明显的影响。造成养殖区水域的DO、pH下降,TN升高,不同季节和不同的水层影响存在差别。冬季对浅层的DO、pH产生明显下降,影响区域小;春季对表层的DO、pH产生明显下降,影响区域大;夏季受水温分层,影响不明显;秋季造成各层水体DO、pH下降,TN上升,影响区域大。千岛湖网箱养殖在春季和秋季对养殖区局部水域影响明显,但分散的网箱养殖对水域影响范围较小,对千岛湖水体短期内影响不明显。  相似文献   

10.
为了解三沙湾大型底栖动物群落结构以及区域内水产养殖活动对其产生的影响,依据2016年夏季采集的样品数据,分析底栖群落结构、群落与环境因子的相关性以及典型群落参数在不同类型水域(鱼类网箱、海带吊绳、鲍鱼筏式养殖水域和自然水域)间的差异。结果表明,三沙湾共发现大型底栖动物6门75种,群落丰度和生物量均值分别为371.34个·m~(-2)和21.82 g·m~(-2)。其中,丝异须虫(Heteromastus filiformis)、不倒翁虫(Sternaspis scutata)、欧努菲虫(Onuphis eremita)、索沙蚕属一种(Lumbrineris sp.)和角海蛹(Ophelina acuminata)等多毛纲动物为数量优势物种,常在鲍鱼筏式和鱼类网箱养殖水域形成较高种群数量。物种数(N)、丰度(S)、生物量(B)和Shannon-Wiener多样性(H′)、Pielou均匀度指数(J′)、Margalef丰富度指数(d)等群落参数在不同水域之间无显著差异(P0.05)。聚类分析结果显示,区域内群落空间异质性较高,空间差异未反映出水域类型的差别。水深、底层水体温度和盐度、沉积物含水率、粉砂-黏粒比例、总氮含量以及总有机碳含量等环境因子和群落相关性较强。综上,三沙湾底栖群落在群落参数方面与我国沿海温带水域相似,但群落的物种组成和较高的空间异质性较为独特;物种组成可表征网箱养殖活动的底栖生态效应。  相似文献   

11.
建立了基于氮通量物质平衡的象山港海湾养殖生态系统箱式模型。模型模拟的象山港主要生态变量的变化动态与实测数据资料相吻合。模型计算结果表明,生物生产过程的季节变化导致了营养要素(如氮)在可溶性无机状态和有机碎屑状态中的相互转化并呈现周年振荡。象山港总氮输入约2182tonN/a,其中养殖输入和排污输入约各占一半;氮输出途径按比例依次为水交换扩散、养殖业收获和渔业捕捞收获。目前象山港氮输入大于氮输出(约11%),造成海湾无机氮浓度年均升高约42μgN/L。利用模型对不同多品种养殖模式下无机氮浓度的长期变化趋势进行了预测。当前养殖模式下,象山港内无机氮浓度增长幅度较小且逐渐趋于输入输出平衡,而要使象山港海水水质达到国家Ⅲ类标准则需要减少鱼类养殖规模至当前规模的约40%或增加藻类养殖规模至当前养殖规模的20倍。  相似文献   

12.
ABSTRACT: Fish cage farming generates large amounts of organic waste in the form of unconsumed feed and fecal matter, resulting in sediment deterioration and a threat to its own sustainability. Field studies analysed the scale of the impact of fish cage farming on sediment quality, variability of impact and spread of sediment enrichment in the vicinity of a fish farm. Two fish culture sites near the Fukuyama area of the Seto Inland Sea of Japan were chosen for the study. There was a significant difference between the quality of the sediment in aquaculture and non-aquaculture areas. The sediment underlying the fish cage farms was found to be extremely reducing, acidic and sulfidic. Sediment ignition loss did not vary markedly with the season. However, the redox potential and acid volatile sulfide content of aquaculture areas did show some seasonal variation. Sediment encircling a 165 m radius from the center of a farm in Yokota was judged as organically enriched by fish farming. A variation in sediment quality within the two sites and also within the stations was observed. Based on sediment quality, the stations could be categorized as less affected, highly affected or moderately affected.  相似文献   

13.
根据2014年11月,2015年1月、3月和7月在象山港中部养殖海区开展的海洋调查所获得的海水营养盐数据,分析了该海域营养盐含量的季节变化,评价了海水的富营养化状况。结果显示,该海域无机氮平均含量秋季最高,春季次之,冬季最低;活性磷酸盐平均含量秋季最高,夏季次之,冬季最低。对不同养殖区域分析,宁海海藻养殖区和西沪港海带养殖区的无机氮浓度除冬季1个站位点外均劣于国家海水四类水质标准(0.50 mg/L),活性磷酸盐浓度在春、秋两季劣于国家海水四类水质标准(0.045 mg/L)。全年各水层的N/P比值均高于Redfield比值,磷相对缺乏。根据富营养化评价模式,象山港中部养殖海区营养水平属于磷中等限制潜在性富营养型。  相似文献   

14.
This paper presents the development of a simple and generally applicable hydrodynamic method for the estimation of production carrying capacity (PCC) of coastal finfish cage aquaculture. Dimensional analysis was used to find significant and general interdependencies between the hydrodynamics at fish farm locations and particulate wastes deposited on the seafloor by fish farms. Modeled ratios of deposition to emission of particulate wastes underneath fish farms were found to be primarily a function of the flow Reynolds numbers at the farming locations and the non-dimensional settling velocity of emitted wastes. In the non-dimensional model, farming conditions include daily feed rate, proportion of unconsumed feed, and carbon content in feed and fish feces. The relationship can be used to estimate the PCC of floating net cages imposing a threshold value for deposition. Results of in-situ assessments of the benthic impacts of several fish farms in an aquaculture site in the northwest of Bali, Indonesia were used to validate and demonstrate the effectiveness of the method. Predicted results were able to clearly identify fish farms operating beyond ecologically sustainable carrying capacity. The proposed method has broad applicability and could help make decisions regarding the estimation of production potential of individual farms in pristine areas, for providing first estimates in sites that have scarce data, and for assessment, expansion, and optimization of the currently operating aquaculture sites in Southeast Asia, China and potentially other data-poor island nations. As the method relies on dynamic models, it enables straightforward assessments over the entire aquaculture region.  相似文献   

15.
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   

16.
Resource use efficiency in Asian carp farming systems is analysed based on a survey of 2493 farms of nine countries. Multivariate classification of farms by intensity and diversity identified six farm types: four types of specialized aquaculture farms at different levels of intensity, and two types of integrated agriculture–aquaculture systems. Pond‐based, specialized semi‐extensive systems (using mainly inorganic fertilizers and feeds of off‐farm origin), and integrated semi‐intensive systems (using feeds and fertilizer of both on and off‐farm origin) are by far the most common types, accounting for 59% and 27% of all farms respectively. Specialized semi‐extensive systems also show the highest protein and nutrient (N and P) use efficiencies, and among the highest labour use efficiency. Super‐intensive cage farms are less efficient in nutrient and labour use, but provide very high returns to land and capital investment. On average, the aquaculture components of integrated agriculture– aquaculture systems are less nutrient, land, and labour efficient than specialized semi‐extensive systems. Integrated semi‐extensive systems (using organic fertilizers of on‐farm origin) are particularly inefficient across all indicators. Hence in practice, gains in overall resource use efficiency through on‐farm integration with agricultural production are constrained by the relative inefficiency of the aquaculture subsystems on integrated farms. Although such systems can likely be improved, integration as such is not a panacea to increasing resource use efficiency. Wide variation in resource use efficiency within all systems indicates potential for substantial efficiency gains through improved management regardless of the fundamental choice of system.  相似文献   

17.
Abstract

We evaluate the profitability and technical efficiency of aquaculture in the Philippines. Farm‐level data are used to compare two production systems corresponding to the intensive monoculture of tilapia in freshwater ponds and the extensive polyculture of shrimps and fish in brackish water ponds. Both activities are very lucrative, with brackish water aquaculture achieving the higher level of profit per farm. Stochastic frontier production functions reveal that technical efficiency is low in brackish water aquaculture, with a mean of 53%, explained primarily by the operator's experience and by the frequency of his visits to the farm. In freshwater aquaculture, the farms achieve a mean efficiency level of 83%. The results suggest that the provision of extension services to brackish water fish farms might be a cost‐effective way of increasing production and productivity in that sector. By contrast, technological change will have to be the driving force of future productivity growth in freshwater aquaculture.  相似文献   

18.
The concept of integrating aquaculture with irrigated farming systems was evaluated in three projects in the GoulburnMurray Irrigation District (GMID) in south-eastern Australia. (1) Semi-intensive cage culture trials using silver perch, Bidyanus bidyanus (Mitchell), were undertaken in a range of irrigated farming systems: irrigation supply channels; groundwater supplies; and on-farm storage dams. Survival and growth of fish under these conditions were comparable to fish reared in conventional aquaculture ponds. However, poor water quality at some sites reduced survival and growth. (2) A study was undertaken to assess the feasibility of the cage culture of silver perch and rainbow trout, Oncorhynchus mykiss (Walbaum), in three irrigation water storage reservoirs. Conditions within each reservoir, particularly water quality, wind and wave action, and cage fouling, varied considerably, and influenced fish growth and survival. (3) Mariculture trials were undertaken in two saline groundwater evaporation basins, which were part of an integrated agriforestry and salt reclamation system. The species tested included two oyster, two prawn and nine fish species. Some species exhibited exceptional survival and growth rates under trial conditions. These projects indicate that the concept of integrating aquaculture with existing irrigated farming systems has the potential to enhance productivity, water use efficiency and overall environmental sustainability in the GMID.  相似文献   

19.
To determine the fate of organic matter derived from fish cage aquaculture, carbon and nutrient cycling processes in waters and sediments, and water circulation, were examined at two fish cage farms of different size and utilizing different food types, on Sulawesi and Sumatra islands, Indonesia. Mass balance models of C, N and P were constructed to assess the pathways of waste utilization and dispersal. At the smaller farm in Sulawesi (64.5 m2 cage area; 3 t annual net production) using pelleted food, there was proportionally less waste (≈ 40% of total C input) than at the larger Sumatran farm (2432 m2 cage area; 9 t annual net production) using trash fish (≈ 70% of total C input) as food. At the small farm, the mass balance and hydrographic models indicated a maximum dispersal area of 1180 m2, equivalent to 18 times the farm area. Within this area, 30% of total organic matter input (farm waste + fixed phytoplankton carbon) was buried in sediments with 30% mineralized in the water-column and 40% mineralized in the seabed. At the larger Sumatran farm, the models indicated a maximum dispersal area of 29  220 m2, roughly 12 times the farm area. Within this area, 30% of total organic matter input (farm waste + natural pelagic input) was buried in sediments with 50% mineralized in the water-column and 20% mineralized on the seabed. There was some evidence of benthic enrichment at both farms, mostly as enhanced dissolved nutrient release, but sulfate reduction accounted for < 25% of total C flux, and denitrification/ammonium oxidation accounted for only 4–17% of N lost from sediments. There was no clear evidence of impact with distance from the cages at either farm. Phytoplankton gross primary production accounted for 60–77% of the total organic input to the receiving environment, suggesting that the relative importance of fish cage wastes must be assessed against natural inputs of organic matter.  相似文献   

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