共查询到20条相似文献，搜索用时 0 毫秒
1.
本研究以2012-2013年长江口鱼类资源密度分布为基础,通过动态生物气候分室模型(DBEM)预估了不同气候变化情景下(IPCC,RCP2.6、RCP6.0和RCP8.5)长江口鱼类资源密度增量分布的变化.在RCP2.6、RCP6.0和RCP8.5这3种气候变化情景下,鱼类资源密度增量、底层鱼类资源密度增量随着时间推移均呈递增趋势,且递增程度和增量重心分布范围随着温室气体排放的增加而扩大(RCP8.5＞RCP6.0＞RCP2.6).鱼类资源密度增量重心主要分布在长江口崇明岛沿岸水域,长江口外侧水域资源密度增量相对较低,并且资源密度增量重心有向南迁移的趋势. 相似文献
2.
本研究采用层次灰色综合评价模型,结合动态生物气候分室模型预估的长江口和黄河口鱼类资源密度增量分布结果,对不同气候变化情景(RCP2.6、RCP6.0和RCP8.5)对长江口和黄河口渔业生态系统健康的潜在影响进行了分析.从生态环境、生物群落结构和生态系统功能三个层面构建了长江口和黄河口渔业生态系统健康评价体系.2015-2050年,长江口和黄河口渔业生态系统健康水平随着温室气体排放程度的增加而降低,即RCP2.6情景下健康水平最高,RCP6.0情景次之,RCP8.5情景最低.两个河口的健康水平随时间推移在RCP2.6情景下呈现出“高-低-高”的变化趋势;在RCP6.0情景下呈现出“低-高-低”的变化趋势;在RCP8.5情景下两个河口略有差异,黄河口呈“高-低-高”的变化趋势,长江口呈“低-高-低”的变化趋势.若以2050年渔业生态系统健康水平作为“最终状态”,两个河口RCP2.6情景下的健康水平高于RCP6.0和RCP8.5情景:长江口RCP2.6情景下的健康评价值为0.61,是RCP6.0和RCP8.5情景下健康评价值的1.9倍和1.8倍;黄河口RCP2.6情景下的健康评价值分别是RCP6.0和RCP8.5情景的2.8倍和2.2倍. 相似文献
3.
全球气候变化导致的海洋环境改变将对海洋生物适宜栖息地产生潜在影响。利用“珊瑚杀手”——长棘海星(Acanthaster planci ) 及其重要捕食者——褐拟鳞鲀 (Balistoides viridescens ) 的发生数据及环境变量,基于BIOMOD2建模平台中的7个模型算法构建物种分布组合模型,模拟它们在当前环境及未来不同气候情景下的潜在适宜生境分布情况。结果表明：1) 长棘海星与褐拟鳞鲀投票平均 (Committee Averaging, CA) 和概率加权平均 (Weighted Mean of Probabilities, WM) 组合物种分布模型的真实技巧统计 (True skill statistic, TSS)、受试者操作特征曲线 (Receiver operating curve, ROC) 值分别为0.96、0.99与0.97、0.99,优于多数单一模型结果,可较好地预测两物种的空间分布格局。2) 温度和离岸距离是影响长棘海星分布的主要因素,而影响褐拟鳞鲀空间分布的主要因素为温度、溶解氧浓度和离岸距离。3) 当前长棘海星与褐拟鳞鲀潜在适宜生境主要位于澳大利亚大堡礁、印度尼西亚、中国南海以及红海海域,褐拟鳞鲀的潜在适宜生境比长棘海星更广泛,未来气候情景条件下,两物种的潜在分布范围总体均有所扩大,且有向高纬度地区迁移的趋势。 相似文献
4.
根据2013年在山东海阳近海海域生产的15艘渔船的渔捞日志,初步分析了该海域渔业资源的种类组成及生物多样性特征。全年共捕获渔业资源种类25种,隶属于14目、21科、25属,鱼类有16种,以暖温种和暖水种为主,虾蟹类4种,头足类2种,水母类2种,多毛类1种。优势种类主要为黄鮟鱇(Lophius litulon)、蓝点马鲛(Scomberomorus niphonius)及口虾蛄(Oratosquilla oratoria)、海蜇(Rhopilema esculentum)、三疣梭子蟹(Portunus trituberculatus)、日本蟳(Charybdis japonica)、中国明对虾(Fenneropenaeus chinensis)等。其中,口虾蛄为全年优势种。渔业资源群落多样性指数和丰富度指数春季最高,秋季次之,夏季最低,通过与山东近海历史调查数据对比可知,该海域渔业资源量大幅下降;均匀度指数(0.13~0.73)变化较小;海阳近海春季和秋季种属组成相似性较高。本研究可为海阳近海渔业资源管理和修复提供参考依据。 相似文献
5.
Valerio Bartolino Piotr Margonski Martin Lindegren Hans. W. Linderholm Massimiliano Cardinale David Rayner Håkan Wennhage Michele Casini 《Fisheries Oceanography》2014,23(3):258-269
Climate change and anthropogenic disturbances may affect marine populations and ecosystems through multiple pathways. In this study we present a framework in which we integrate existing models and knowledge on basic regulatory processes to investigate the potential impact of future scenarios of fisheries exploitation and climate change on the temporal dynamics of the central Baltic herring stock. Alternative scenarios of increasing sea surface temperature and decreasing salinity of the Baltic Sea from a global climate model were combined with two alternative fishing scenarios, and their direct and ecosystem‐mediated effects (i.e., through predation by cod and competition with sprat) on the herring population were evaluated for the period 2010–2050. Gradual increase in temperature has a positive impact on the long‐term productivity of the herring stock, but it has the potential to enhance the recovery of the herring stock only in combination with sustainable fisheries management (i.e., Fmsy). Conversely, projections of herring spawning stock biomass (SSB) were generally low under elevated fishing mortality levels (Fhigh), comparable with those experienced by the stock during the 1990s. Under the combined effects of long‐term warming and high fishing mortality uncertainty in herring SSB projections was higher and increasing for the duration of the forecasts, suggesting a synergistic effect of fishery exploitation and climate forcing on fish populations dynamics. Our study shows that simulations of long‐term fish dynamics can be an informative tool to derive expectations of the potential long‐term impact of alternative future scenarios of exploitation and climate change. 相似文献
6.
福建东山湾渔业资源现状调查研究 总被引：1，自引：0，他引：1
根据2012—2013年在东山湾海域进行的4个季度航次的渔业资源调查资料,对该海域鱼卵、仔稚鱼及游泳动物组成特征进行了初步研究。结果表明,4个季度航次调查共鉴定出鱼卵15种,仔稚鱼8种(含5个未定种),鱼卵平均密度为2.63个/m3,仔稚鱼平均密度为0.50ind/m3。共出现游泳动物269种,其中鱼类种类数最多,为202种;从季节分布来看,夏季游泳动物种类数最多(161种),冬季最少(62种);从平面分布来看,夏季5号调查站位游泳动物种类数最多(95种),9号调查站位最少(12种)。本次调查,游泳动物重量资源密度平均值冬季最高(1 246.98 kg/km2),春季最低(372.68 kg/km2),尾数资源密度平均值春季最高(36.04×103ind/km2),冬季最低(11.25×103ind/km2);4个季度月优势种均不同,表现出明显的季节更替现象;全年游泳动物重量密度多样性指数表现为秋季夏季春季冬季,丰富度指数d均值为3.49,均匀度指数J'均值为0.64,单纯度指数C均值为0.23;全年游泳动物尾数密度多样性指数表现为夏季冬季春季秋季,丰富度指数d均值为7.09,均匀度指数J'均值为0.70,单纯度指数C均值为0.18。与历史资料相比,本次调查鱼卵仔稚鱼密度四季均值较高,游泳动物种类数较多、重量和尾数密度四季均值较大、物种多样性较高。 相似文献
7.
8.
闽东近海张网渔业监测分析 总被引：1，自引：0，他引：1
根据2009-2010年福建省渔业统计资料及闽东近海张网作业监测调查资料,分析了闽东近海张网渔业概况、监测船生产情况、渔获结构变化及主要种类的渔获状况。结果显示,张网作业监测船平均网产为65.0～79.3kg,渔获物以小型大宗鱼类为主,占总渔获量的68.7%;带鱼(Trichiurus haumela)占总渔获量的3.40%～6.97%,七星底灯鱼(Myctophum pterotum)、麦氏犀鳕(Bregmaceros maecelellandii)、龙头鱼(Harpodon neherus)、黄鲫(Setipinna taty)等低质鱼的渔获重量比例近年来渐渐增高。 相似文献
9.
Ledhyane Ika Harlyan Takashi Fritz Matsuishi Mohammad Faisal Md Saleh 《Fisheries Management and Ecology》2021,28(2):126-137
Malaysian fisheries employ multiple measures to improve management; however, not all are well-suited to the multispecies fisheries. As part of a pilot project, an individual quota system was introduced for the purse-seine fishery off the East Coast of Peninsular Malaysia (ECPM), but no assessment of this particular measure nor the feasibly of its implementation has been confirmed. Therefore, this study analysed spatial and temporal patterns of purse-seine fishing, by collecting catch composition data per landing and its fishing ground within three period fishery surveys between August 2017 and September 2018 at six different landing sites. Similarity and cluster analysis examined species composition and diversity to determine the feasibility of implementing a single-species quota system in this multispecies fishery. Some overlapped of indices results and minor difference in catch composition were found due to changes in spatial and temporal fishing activities. However, no specific spatial or temporal patterns were discernible as structuring the fishing grounds used by purse-seiners. The absence of patterns, using the available data, might be attributable to huge species aggregations and widely distributed and homogenously mixed fish stocks. Thus, it is likely impractical to manage species individually in such a multispecies fishery. 相似文献
10.
2002～2003年对水口闽清库区、永定棉花滩水库、泰宁大金湖等渔业生态环境进行监测，监测结果表明：福建省淡水渔业水域大部分水质良好，只有九龙江流域龙岩段的水质处于污染状态，主要污染项目是总磷、亚硝酸盐和非离子氨；沉积物有机质超标，生物体内铅含量超标。 相似文献
11.
海南岛近岸海域鱼类物种组成和多样性的季节变动 总被引：2，自引：0，他引：2
根据2006年～2007年间在海南岛近岸海域进行的4个航次底拖网调查资料,分析了该海域鱼类物种组成和生物多样性特征。发现该海域鱼类种类较为丰富,调查共采集到鱼类292种,隶属于21目100科172属;其中暖水性种类数占83.32%,暖温性种类数占16.78%;与中国黄渤海共有种76种,与东海共有种220种,与南海大陆架、大陆坡和南海诸岛海域共有种分别为279种、42种和51种。鱼类优势种[相对重要性指数（IRI）〉500]依次为发光鲷（Acropoma japonicum）、斑鳍天竺鱼（Apogonichthys carinatus）、黄斑鲾（Leiognathus bindus）、皮氏叫姑鱼（Johnius belengeri）、大头白姑鱼（Argyrosomus macrocephalus）、（Therapon theraps）、棕斑腹刺鲀（Gas-trophysus spadiceus）和麦氏犀鳕（Bregmaceros macclellandi）。以生物量为基础采用5个指数研究了该海域鱼类多样性现状,并采用季节更替指数（AI）和迁移指数（MI）对各季节鱼类群落的稳定性进行了分析。结果显示,该海域鱼类多样性水平较高,相邻季节的鱼类物种相似性也较高,随着鱼类的洄游,群落的稳定性出现较大波动。 相似文献
12.
13.
14.
15.
16.
17.
Characterization of the fishery in river communities in the low-Solimões/high-Amazon region 总被引：1，自引：0，他引：1
V. S. BATISTA A. J. INHAMUNS C. E. C. FREITAS D. FREIRE-BRASIL 《Fisheries Management and Ecology》1998,5(5):419-435
Questionnaires were used to collect data from the low-Solimões/high-Amazon region, Brazil, between December 1992 and February 1994. Gillnets, fishing rods and castnets were the preferred gear used. Gillnets were used throughout the year whilst other gears were used only in certain periods of the year. The fish caught tended to supply family needs but a high proportion were sold in regional markets. Curimatã (Prochilodus nigricans), pacu (various Myleinae) and ruelo (young Colossoma macropomum) were the most frequent species caught. Around 50% of the fish caught in these fisheries was consumed fresh, and the remainder was stored under ice or salted. Fish is the most important source of animal protein for this region, with an annual mean consumption rate of 550 g capita?1 day?1. The fishery has changed from a subsistence to a commercial scale, which was associated with increasing cattle ranching activities. This may have serious social and economic implications. 相似文献
18.
浙江沿海渔业资源放流增殖的回顾与展望 总被引：11，自引：2，他引：11
本文对20世纪50年代以来浙江沿海渔业资源的放流和增殖(移植)工作进行了综述,总结了近20年来实施对虾、海蜇、石斑鱼、大黄鱼、黑鲷等增殖放流的经验和教训,并对存在的问题和今后的工作提出了建议。 相似文献
19.
20.
Mafalda Gama Daniel Crespo Marina Dolbeth Pedro Manuel Anastácio 《水产资源保护:海洋与淡水生态系统》2017,27(3):675-684
- Global biodiversity is at risk owing to climate change, and freshwater ecosystems are expected to suffer the most. In recent years niche‐based models (NBMs) have been used to predict species distribution and are an important tool for conservation and management of aquatic ecosystems. In this work, the current and future climatic suitability areas of the invasive species Corbicula fluminea, which has known adverse ecological and economic impacts, were investigated.
- The species distribution modelling was based on nine algorithms in BIOMOD2, summarized in an ensemble forecasting approach. To model the species distribution, eight climatic parameters related to temperature and precipitation variables were considered. Three time frames (current, 2050 and 2070) were modelled using four increasing CO2 emission scenarios.
- The performance of individual models was excellent according to the area under the receiver operating characteristic curve (AUC) and good to excellent according to true skill statistics (TSS). Annual mean temperature, minimum temperature of the coldest month and mean temperature of the coldest quarter were the most important variables predicting C. fluminea occurrence. Of the total continental area, 6.6% was predicted to be suitable for C. fluminea in current conditions.
- In the future, suitable area will increase from the current value of 6.6% to values from 9.4% to 12.6%, according to the 2050 projections and up to 12.7% in 2070 in high emission scenarios.
- Overall, the results indicate that climate change will favour the expansion of C. fluminea into new river basins, especially at higher latitudes, and that future climatic scenarios may double the suitable area for Corbicula fluminea.