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1.
为了解浙江省大陈洋产卵场保护区甲壳类的群落结构特征,于2018年春季(4月)和秋季(11月)对甲壳类生物资源进行了底拖网调查,应用相对重要性指数(IRI)、生物多样性指数和典范对应分析(CCA)等方法对其群落结构及其与环境因子的关系进行了综合分析。结果表明: 共鉴定出甲壳类38种,隶属14科25属,其中口虾蛄、三疣梭子蟹、双斑蟳和哈氏仿对虾为优势种。春季甲壳类资源密度在50 m以浅海域较高;秋季在50 m以深海域较高,且保护区内南部甲壳类资源密度高于北部。关于多样性特征,春季甲壳类丰富度指数(D)、多样性指数(H)和均匀度指数(J)均高于秋季,空间分布上50 m以深海域甲壳类的H最高。根据生物量进行等级聚类分析(CLUSTER)和非度量多维标度排序(NMDS)分析,春季可将甲壳类划分为3个群落,秋季划分为4个群落,春季甲壳类群落结构组内差异性较秋季显著。典范对应分析结果表明,水深、底温、盐度和溶解氧为影响甲壳类种类组成和时空变化的主要环境因子。  相似文献   

2.
太湖渔业发展及区域设置与功能定位   总被引:11,自引:1,他引:10  
渔业是太湖的重要功能之一.太湖渔业主要以自然捕捞和围网养殖为主.目前太湖自然渔业捕捞强度及东太湖湾围网养殖的超常规发展,给湖泊生物资源带来巨大影响.依据太湖生物资源现状和分布,借助太湖遥感解译图像,定位设置太湖各类生物资源恢复与保护的功能区域,包括东部的资源保护核心区、缓冲区(湿地生态景观带)和西部的生态恢复区等.其管理目标是太湖水环境、渔业资源和生物多样性及环湖湿地、自然景观的保护,加快太湖生态恢复进程,促进旅游业和渔业的健康发展,实现太湖渔业资源的有序利用和可持续发展.  相似文献   

3.
复合种群管理的风险评估——以日本鲐为例   总被引:3,自引:0,他引:3  
官文江  高峰  李纲  陈新军 《生态学报》2014,34(13):3682-3692
单一种群是目前渔业资源评估的基本假设,但渔业资源常由多个地方种群或产卵种群组成,并且种群间存在交流,构成复合种群。根据复合种群概念,以东、黄海日本鲐为例,对其12种种群动态情况进行了模拟。利用模拟所得的数据及剩余产量模型,分别分析了在复合种群、两独立种群及单一种群假设下所设置的10种评估管理方案,结果表明:(1)基于复合种群假设的评估管理方案与模拟的种群动态一致,在单位捕捞努力量渔获量(CPUE)观测误差较小情况下,该方案为最佳方案,可获得最大可持续产量,但随CPUE观测误差增大,该方案种群灭绝率增大,管理效果随之退化。(2)基于两独立种群假设的评估管理方案均使资源过度开发,不利于资源可持续利用。(3)在单一种群假设下,选择不同CPUE作为资源指数和采用不同捕捞量分配方法的评估管理方案存在过度捕捞和开发不足两种状况,其管理效果受种群本身参数及空间交换率等因素的影响而不同;若采用的CPUE反映部分种群动态信息,则其评估管理方案至少在一种模拟情况下出现种群100%灭绝;若CPUE能反映整个种群资源量的动态变化,且捕捞量能按种群的空间结构进行分配,则管理效果与(1)类似,但不能获得最大可持续产量,若忽略种群的空间结构影响而均匀分配捕捞量,则至少在一种模拟情况下出现种群100%灭绝。据此,对于复合种群的管理,建议:(A)如果种群数据收集及数据精度能得到保证,该资源的评估与管理应基于复合种群假设;(B)如果目前收集种群数据存在较大困难,且CPUE数据存在较大误差,则可采用单一种群假设,但必须设定更保守的捕捞量和采用基于种群空间结构的总许可渔获量(TAC)管理方案;(C)在制定渔业管理政策时,应结合种群生态、数据、模型假设及参数估计方法等方面的不确定性对管理控制规则进行系统的管理策略评价以避免风险。  相似文献   

4.
董天  郑华  肖燚  欧阳志云 《生态学杂志》2017,28(8):2605-2610
分区旅行费用模型(ZTCM)和旅行费用区间模型(TCIA)是两种常用的旅游资源使用价值评估方法,但两种模型因构建的出发点不同而可能导致不同的研究结果.比较两种方法的评估结果对于准确评估旅游资源使用价值具有重要意义.本文采用问卷调查,应用ZTCM和TCIA对北京奥林匹克森林公园的使用价值进行评估.结果表明: 基于ZTCM,研究区的景观使用价值为162.36亿元;基于TCIA,景观使用价值为37.32亿元.与ZTCM相比,TCIA对追加费用和旅游人数的拟合度更高.对于同一出发地旅行费用差异较大的样本,TCIA可以有效改进ZTCM假设同一出发地平均消费一致的前提,研究结果更符合实际,更适合准确评估旅游资源的使用价值.  相似文献   

5.
年龄是渔业种群动态模型及渔业资源评估中非常重要的参数之一。不像有鳍鱼类,可以通过钙化组织(如,耳石、鳍条和脊椎骨等)鉴定年龄,甲壳类动物因复杂的蜕壳过程使得可用的钙化结构周期性消失,因此甲壳类年龄鉴定一直以来均未得到较好的解决。虽然过去较长一段时间内,体长频度法用于鉴定甲壳类年龄,但其结果仍存在着较大的不确定性。脂褐素因其浓度随生物年龄增长而增加,因此在形态学测量与年龄无相关性时,其也成为近年来许多甲壳类鉴龄研究中的年龄生物标记。为了更深入地了解该鉴龄手段及其在甲壳类鉴龄中的应用,本研究阐述了脂褐素鉴定该类动物年龄的研究进展,介绍了脂褐素的组成及生物学特性,探讨了脂褐素含量与体长、年龄之间的关系,并通过组织形态法及溶剂提取法对脂褐素含量量化技术进行了阐述,详细分析了3种较为常用的脂褐素校准方法。最后,对脂褐素鉴龄提出了自己的见解及今后的研究方向。  相似文献   

6.
杜国英  陈尚  夏涛  王敏  张涛  赵志远 《生态学报》2011,31(19):5553-5560
海洋生态资本是沿海地区社会经济活动的重要生产要素,海洋生物资源是海洋生态资本的关键构成要素之一。采用《海洋生态资本评估技术导则》中的方法,评估了山东近海生物资源现存量价值。结果表明,2006年山东近海生物资源现存量为100.20万吨,价值184.45亿元。生物资源以鱼类资源为主,资源量为76.50万吨,价值约131.73亿元,占全省近海生物资源总价值的71.4%;甲壳类资源量为13.98万吨,价值38.88亿元,占总价值的21.1%;头足类资源量为3.52万吨,价值4.47亿元,占总价值的2.4%;其他类海蜇资源量为6.46万吨,价值9.37亿元,占总价值的5.1%。全省近海生物资源现存量价值平均为58.4万元/km2。山东近海生物资源存量价值与近海供给服务价值、气候调节服务价值和物种多样性维持服务价值之间表现出互相促进的关系。本研究结果有助于提高人们对海洋生物资源重要性的认识,为海洋生物资源的可持续利用提供决策依据。  相似文献   

7.
<正>由教育部主管、武汉大学主办的《氨基酸和生物资源》于2016年4月获国家新闻出版广电总局批准,更名为《生物资源》,出版物号为CN42-1886/Q。该刊创刊于1975年,历经40年的发展,报道了一批以氨基酸为特色的研究成果,是中国科技核心期刊。《生物资源》将在2017年正式编辑出版。主要刊载动植物资源、遗传资源和微生物资源的生物学基础研究成果,生物资源利用与评估应用技术,生物资源多样性及保护利用进展。  相似文献   

8.
英特网上生物信息资源的利用   总被引:17,自引:0,他引:17  
充分利用英特网上完善的生物信息资源是十分有益且必要的.介绍了利用网上生物资源的几种主要方式和一些重要的站点和生物信息搜索引擎.  相似文献   

9.
应用稳定同位素技术测定了大凌河、鸭绿江近岸海域春季主要渔业生物的碳氮稳定同位素比值,计算主要生物种类的营养级,构建了河口近岸海域主要生物种类的连续营养谱。结果表明:大凌河、鸭绿江近岸海域主要生物的δ15N、δ13C值范围分别为8.2‰~14.1‰、-22.9‰~-16.6‰,7.9‰~13.2‰、-20.6‰~-16.1‰;大凌河口海域主要生物资源种类营养级范围为2.8~3.9,其中,甲壳类为2.9~3.5,腹足类为2.8~3.1,双壳类为2.9~3.4,鱼类为3.4~3.9;鸭绿江口海域主要生物资源种类营养级范围为2.8~3.7,其中,甲壳类为3.0~3.6,头足类为3.4~3.5,腹足类为2.8~3.0,双壳类为2.9~3.2,鱼类为3.1~3.7;连续营养谱显示,两个河口近岸海域初级消费者主要为泥螺、四角蛤蜊,两个河口近岸海域次级消费者主要为甲壳类,高级消费者同为鱼类。本研究初步建立了大凌河口、鸭绿江口近岸海域主要渔业生物的连续营养谱,为渔业资源的保护及开发利用提供基础数据。  相似文献   

10.
杜仲是我国特有的珍稀生物资源,杜仲产业属于我国的战略新兴产业.国家林业局于2016年12月发布了《全国杜仲产业发展规划》(2016-2030年),阐述了杜仲产业开发面临新的机遇以及生物资源管理方面的问题.本文在阐述生物多样性与生物资源管理概念和进展的基础上,分析了杜仲产业规划区及杜仲生物资源产业开发的有关问题,提出将杜仲产业开发上升到生物资源层面,从生物多样性、生物质资源和生物信息资源等方面加强规划和科学管理的有关建议.  相似文献   

11.
12.
This review is based on 58 climate-fisheries models published over the last 28 years that describe the impacts of fishery pressure and environmental variability on populations and ecosystems and include basic principles of population dynamics. It points out that the incorporation of environmental factors in fishery models has already been done and is of great importance for future models used in the assessment of marine resources. The work is guided by the questions to what extent have these models a) enhanced our understanding of the interrelationships between the environment, the fishery and the state of the exploited resources and b) helped to improve the prediction of population dynamics and the assessment of marine resources. For each of the six most commonly used model categories a case study is critically analyzed. The problems of “breaking relationships” between environmental factors and the biological response used in models, the trade-off between model complexity (realism) and simplicity (data availability) and the potential of multivariate climate indices for forecasting ecosystem states and for use as proxies for combined models are discussed, as are novel non-linear and spatially explicit modeling approaches. Approaches differ in terms of model complexity, use of linear or non-linear equations, number of parameters, forecast time horizon and type of resource modelled. A majority of the models were constructed for fish and invertebrate stocks of the northeast Pacific and the epicontinental seas of the Atlantic, reflecting the advancement of fisheries science in these regions. New, in parts highly complex models and sophisticated approaches were identified. The reviewed studies demonstrate that the performance of fished stocks can better be described if environmental or climatic variability is incorporated into the fisheries models. We conclude that due to the already available knowledge, the greatly enhanced computer power, new methods and recent findings of large-scale climatic/oceanographic cycles, fisheries modeling should progress greatly in the coming years.  相似文献   

13.
Fish populations vary geographically in demography and life history due to environmental and ecological processes and in response to exploitation. However, population dynamic models and stock assessments, used to manage fisheries, rarely explicitly incorporate spatial variation to inform management decisions. Here, we describe extensive geographic variation in several demographic and life history characteristics (e.g., size structure, growth, survivorship, maturation, and sex change) of California sheephead (Semicossyphus pulcher), a temperate rocky reef fish targeted by recreational and commercial fisheries. Fish were sampled from nine locations throughout southern California in 2007-2008. We developed a dynamic size and age-structured model, parameterized separately for each location, to assess the potential cost or benefit in terms of fisheries yield and conservation objectives of changing minimum size limits and/or fishing mortality rates (compared to the status quo). Results indicate that managing populations individually, with location-specific regulations, could increase yield by over 26% while maintaining conservative levels of spawning biomass. While this local management approach would be challenging to implement in practice, we found statistically similar increases in yield could be achieved by dividing southern California into two separate management regions, reflecting geographic similarities in demography. To maximize yield, size limits should be increased by 90 mm in the northern region and held at current levels in the south. We also found that managing the fishery as one single stock (the status quo), but with a size limit 50 mm greater than the current regulations, could increase overall fishery yield by 15%. Increases in size limits are predicted to enhance fishery yield and may also have important ecological consequences for the predatory role of sheephead in kelp forests. This framework for incorporating demographic variation into fisheries models can be exported generally to other species and may aid in identifying the appropriate spatial scales for fisheries management.  相似文献   

14.
SUMMARY. 1. This paper describes an analysis of results from a questionnaire (Giles, 1987) which requested information on the status of game fish stocks (especially wild brown trout Salmo trutta L.) from those Game Conservancy members who own or manage fisheries. Also included are data arising from fishery log book records which are used to indicate trends in brown trout catch per unit effort (CPUE) over past decades.
2. The key finding from questionnaire returns was the widespread reporting of apparent declines of wild brown trout stocks in a total of twenty-seven sites throughout Britain. The affected waters are geographically widespread from the south-west of England through southern and south-east England, south Wales, northern England and Scotland including the Western Isles. Suspected stock declines of migratory (sea) trout, salmon Salmo salar L. and grayling Thymallus thymallus L. were also reported. Where brown trout occur alone, a significantly higher proportion of questionnaire returns recorded a stock decline compared with fisheries containing both brown and rainbow trout Salmo gairdneri Richardson.
3. Trout catch records from a small selection of differing fishery types are presented and the value of such data in fish stock assessment is discussed.  相似文献   

15.
A genetic stock identification (GSI) study was undertaken in a fishery for Atlantic salmon Salmo salar to determine the effects of restrictive fishery management measures on the stock composition of the fishery, and if accurate and precise stock composition estimates could be achieved on the small geographical scale where this fishery operates, using a suite of only seven microsatellite loci. The stock composition of the Foyle fishery was shown to comprise almost exclusively of Foyle origin fish in the 3 years after restrictive measures were introduced in 2007, compared to 85% the year before. This showed that the restrictive measures resulted in the Foyle fishery being transformed from a mixed‐stock fishery to an almost exclusively single‐stock fishery, and showed how GSI studies can guide and evaluate management decisions to successfully manage these fisheries. Highly accurate and precise stock composition estimates were achieved in this study, using both cBAYES and ONCOR genetic software packages. This suggests accurate and precise stock composition is possible even on small geographical scales.  相似文献   

16.

Bycatch continues to be a challenge to sustainable fisheries management (The term “bycatch” in this paper covers discards and does not include retained incidental catch). Bycatch estimates can inform stock status determinations by improving understanding of fishing mortality, and help managers monitor the effectiveness of regulations. Assessments of the quality of bycatch estimation programs and procedures are necessary to evaluate the precision and limitations of their results over time. NOAA Fisheries experts used a “Tier Classification System” (TCS) to compare the quality of fish bycatch data and estimation methods for U.S. commercial fisheries in 2005 and 2015. The TCS included criteria related to data adequacy and analytical approaches. A comparison of U.S. fishery tier scores demonstrated that most fisheries were classified into higher tiers in 2015 compared to 2005 due to factors including improved sampling design. In addition, this comparison identified region-specific trends (e.g., mostly improvements occurred for Alaska fisheries with more mixed results for Greater Atlantic fisheries). The improvements in bycatch data quality and estimation methods in the United States are a result of financial investments in observer programs by NOAA Fisheries and industry partners, as well as effective conservation measures implemented by regional fishery management councils and NOAA Fisheries. The TCS was also used to assess bycatch data and estimation methods in all of Australia’s fishery jurisdictions for the decade 2010–19, illustrating the international applicability of the method. Overall, Australian state fisheries scored lower than federally managed fisheries in both the United States and Australia, reflecting the fact that the latter fisheries tend to be larger (and more valuable) than those in state jurisdictions, with a larger investment in observer programs. A comparison of tier scores and estimates of discards by fishery may provide a useful input for decision-making processes regarding allocation of resources to improve bycatch monitoring.

  相似文献   

17.
Summary Although all fisheries are multispecies and spatially heterogeneous, coral reef fisheries are an extreme in both respects. The two main approaches to stock assessment have been either to consider individual species separately or to lump all species together. Both are limited in their predictive power. The lack of ecological knowledge and the large number of parameters required make methods based on single species often impractical or expensive. However, where the appropriate information is available, ecological studies do not provide significant improvements on yield-per-recruit or surplus yield models currently used.Alternative community models based on aggregates of species lack predictive power, empirical support and relative data. Models are further limited because they do not address various economic aspects, fish movement and recruitment, all of which must be spatially resolved. However, the ECOPATH model, based on trophic compartments, represents a new approach useful to multispecies assessment, and the only way at present to include predation in stock models. In practice the data available will be the most important factor in the choice of stock assessment model.The major concern for management of many coral reefs is conservation of the habitat and stocks. In some cases this has been achieved with little reference to stock assessment, by using community management and closed areas, which are receiving increasing support. However, once the objective of conservation is achieved, stock assessment should have an important role in improving the economic performance of the fisheries. The wider problems of management have no simple solutions, but managers should look to adaptive management, designing their own experiments to choose between management models.  相似文献   

18.
We consider combinations of three types of control measures for the management of fisheries when the input information for policy decisions is uncertain. The methods considered include effort controls, catch quotas and area closures. We simulated a hypothetical fishery loosely based on the Icelandic cod fishery, using a simple spatially explicit dynamic model. We compared the performance with respect to conserving the resource and economic return for each type of control measure alone and in combination. In general, combining more than one type of primary direct control on fishing provides a greater buffer to uncertainty than any single form of fishery control alone. Combining catch quota control with a large closed area is a most effective system for reducing the risk of stock collapse and maintaining both short and long-term economic performance. Effort controls can also be improved by adding closed areas to the management scheme. We recommend that multiple control methods be used wherever possible and that closed areas should be used to buffer uncertainty. To be effective, these closed areas must be large and exclude all principal gears to provide real protection from fishing mortality.  相似文献   

19.
Traditional fisheries stock assessment methods and fishery independent surveys are costly and time consuming exercises. However fishers trained in data collection and utilising other skills can reduce costs and improve fishery assessments and management. A data collection program was conducted by Australian and Indonesian scientists with small-scale Indonesian sea cucumber fishers to evaluate the approach and then capture its benefits. The data fishers recorded allowed for the first stock assessment of this trans-boundary fishery during its centuries-long existence at Scott Reef in north-western Australia. The program also included interviews with fishers capturing the social, economic, and demographic aspects of the fishery. Economic inputs to fishing were complemented by fishery revenue data voluntarily submitted when fishers returned to port and sold their catch. Catch data recorded by fishers demonstrated much higher abundances than estimates obtained using standard visual transect methods and accurately reflected the true catch composition. However, they also showed extreme rates of exploitation. Interviews revealed social and economic factors that would be important considerations if management interventions were made. The program’s approach and the time scientists spent on the fishers’ vessels were key ingredients to fishers’ participation and the utility of the results. Despite the program’s achievements the information generated has not led to improved management or had any direct benefits for the participants. Sustaining the program in the longer term requires that its value is better captured.  相似文献   

20.
Fisheries stock assessments are essential for science-based fisheries management. Inland fisheries pose challenges, but also provide opportunities for biological assessments that differ from those encountered in large marine fisheries for which many of our assessment methods have been developed. These include the number and diversity of fisheries, high levels of ecological and environmental variation, and relative lack of institutional capacity for assessment. In addition, anthropogenic impacts on habitats, widespread presence of non-native species and the frequent use of enhancement and restoration measures such as stocking affect stock dynamics. This paper outlines various stock assessment and data collection approaches that can be adapted to a wide range of different inland fisheries and management challenges. Although this paper identifies challenges in assessment, it focuses on solutions that are practical, scalable and transferrable. A path forward is suggested in which biological assessment generates some of the critical information needed by fisheries managers to make effective decisions that benefit the resource and stakeholders.  相似文献   

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