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1.
The geographical distribution and production of the Barents Sea capelin (Mallotus villosus, Osmeridae) is modelled by the use of a state-variable optimization technique (dynamic programming), where the main objective of individuals always is to maximize fitness, or total expected reproduction (RO), by selecting the most profitable habitats through time. Fitness is gained by successful reproduction (a function of size) during the spawning season on the breeding grounds off northern Norway. The environment (predators, temperature and zooplankton prey) is determined by a meteorologically forced circulation model for the year 1980, creating a spatial and seasonal fluctuation in the environment. Predation from cod is the main source of mortality, and the distribution of the cod (Gadus morhua) stock is assumed to vary with temperature. Growth is predicted from a bioenergetic model, incorporating the cost of swimming between feeding areas and spawning grounds. Field data of the capelin stock recorded during autumn cruises from 1979 is implemented at the start of the model, and then this stock is modelled through 1980 and the first months of 1981. Model predictions are compared with the observed distribution of capelin in autumn 1980. Habitat selection has consequences for the dynamics of the population and growth of individuals, demonstrating the importance of combining external (environmental) and internal (evolutionary) forcing to understand and predict the dynamics of fish populations. This study is the first application of dynamic programming to model the dynamics and ecology of horizontal fish migration, and we suggest that the method may be developed into a useful tool for the management of short-lived species.  相似文献   

2.
The coastal shelf of northern Norway and the Barents Sea is highly advective and mainly affected by the North Atlantic Current and the Norwegian Coastal Current. The oceanographic conditions are an important factor for the spatial and temporal distribution of zooplankton in the region. To quantify zooplankton advection over the western border of the Barents Sea, a Scanfish/Optical Plankton Counter (OPC), Acoustic Doppler Current Profiler (ADCP), Multiple Opening and Closing Nets and Environmental Sampling System (MOCNESS), and hydrodynamic model were used. This study provides data from two time windows (June and July 1998) by continuous measurements between northern Norway and Bear Island. The zooplankton community structure was obtained by net tows and zooplankton abundance fields were mapped by an OPC counting zooplankton in the size range 0.7–14 mm equivalent spherical diameter. A simple zooplankton community structure was found with the copepod Calanus finmarchicus (CIII–CV) as the dominant species in this size fraction. Ocean currents were measured by a ship‐mounted ADCP and the residual currents were calculated by subtracting the tidal component obtained from a hydrodynamic model. Two measurements conducted in June and July 1998 shows a net eastward transport of water of 3.5 and 1.3 Sverdrup over the section. For the same two periods, zooplankton biomass transport is also positive towards east but varies by two orders of magnitude between the two measurements.  相似文献   

3.
Oceanographic and predation processes are important modulators of fish larvae survival and mortality. This study addresses the hypothesis that immature Norwegian spring‐spawning herring (Clupea harengus), when abundant in the Barents Sea, determine the capelin reproduction success through consumption of Barents Sea capelin (Mallotus villosus) larvae. Combining a hydrodynamic model and particle‐tracking individual‐based model, a realistic spatio‐temporal overlap between capelin larvae and predatory immature herring was modelled for the summer seasons of 2001–2003. Capelin larvae originating from western spawning grounds became widely dispersed during the summer season, whereas those originating from eastern spawning grounds experienced a rapid drift into the southeastern Barents Sea. Herring caused a 3% mortality of the capelin larvae population in 2001 and a 16% mortality in 2003, but the effect of predation from herring on capelin larvae was negligible in 2002. Despite a strong capelin larvae cohort and a virtual absence of predatory herring, the recruitment from the capelin 2002 year class was relatively poor from a long‐term perspective. We show that the choice of capelin spawning grounds has a major impact on the subsequent capelin larvae drift patterns, constituting an important modulator of the capelin larvae survival. Variation in drift patterns during the summer season is likely to expose the capelin larvae to a wide range of hazards, including predation from young cod, sandeel and other predators. Such alternative predators might thus have contributed to the poor capelin recruitment during 2001–2003, leading to the collapse of the capelin stock in the subsequent years.  相似文献   

4.
2003年东海及部分黄海海域表面水温状况分析   总被引:3,自引:4,他引:3  
本文分析了2003年东海及部分黄海海域的表面温度状况。研究表明,不同的水团具有不同的温度年变化特点。大陆水系的均极差远大干多年平均的水平,说明沿岸海域的表面温度年变化比常年更大,但黑潮主干区的均极差却和多年平均值差不多。虽然各海域的温度季节变化因海区的不同略有不同,但各种水团的年平均温度比多年平均都要高一些,说明这一年是比较温暖的一年。  相似文献   

5.
2006年东海及部分黄海海域表面水温状况分析   总被引:1,自引:0,他引:1  
分析了2006年东海及部分黄海海域的表面温度状况。研究表明,不同的水团具有不同的温度年变化特点,大陆水系的均极差远大于多年平均水平,说明沿岸海域的表面温度年变化比常年更大,同时黑潮主干区的均极差也比多年平均值高,所以,无论是沿岸海域还是暖流区,2006年的表面温度变化都比常年剧烈。暖流中黑潮暖流、对马暖流以及黄海暖流总体状况与多年平均差不多;而台湾暖流则在2006年大部分时间中保持比多年平均略高的状态。沿岸海域中偏南的区域水温高于多年平均,偏北的区域则与常年差不多,特别是福建沿岸、浙江沿岸和长江口及邻近区域在春季出现了温度偏高的状况。此外,值得注意的是2006年秋季黄、东海区大部分海域的表面温度呈现比多年平均略偏高的状态。  相似文献   

6.
章守宇 《水产学报》2003,27(3):265-272
基于磷营养盐的变动由线性趋势和周期性波动构成的假设,构建了东海磷营养盐变动模型;提出了对非等间隔时间序列实测数据求解周期等模型参数的逐步选择法。运用模型对东海磷营养盐的历史调查资料进行验证及预测检验均取得了良好效果。分析还表明,周期性成分引起的波动对东海磷酸盐变动的影响要比相应的趋势项成分大得多;模型的构成周期中并没有特别卓越的成分在其中起支配作用,决定东海磷酸盐变动的是多个时间尺度上的周期性现象的共同作用。  相似文献   

7.
To include the effects of environmental factors on the production of small yellow croaker, Pseudosciaena polyactis Bleeker, in the Yellow Sea, we applied time series analysis to the commercial catch and salinity and temperature data for the period 1970 to 1988. Residuals from a weighted least-squares regression of log-transformed catches against year and month were calculated to remove not only seasonal factors but also long-term trends in catches. The residuals of mean and standard deviation (SD) of temperature and salinity were calculated and used for autocorrelation, cross-correlation and first-order autoregression analysis (AR(1)) using maximum likelihood. The landings showed a decreasing pattern across years with a conspicuous seasonal cycle within years. Catch residuals showed a strong positive autocorrelation and a conspicuous time-lagged cross-correlation with the residuals of mean and SD of seawater temperature at 75␣m. AR(1) revealed that positive anomalies of mean temperature were associated with positive anomalies in the production of small yellow croaker with a one year time lag. The decrease in the residual of SD of temperature appears to be related to the high production 0.5–1.0 year later. The effect of salinity was negligible compared with that of temperature. Therefore, the warm spawning period and homogeneous temperature condition of previous years for young fish may cause the increase in the following year's yield of this fish species. When used to predict catches in 1989 and 1990, the AR(1) model explained 40% of the variances of the observed landings.  相似文献   

8.
南海鸢乌贼产量与表温及水温垂直结构的关系   总被引:3,自引:1,他引:3  
根据2012年9—10月秋季航次及2013年3—4月春季航次南海灯光罩网船各站点的水温数据及生产数据,对鸢乌贼(Symplectoteuthis oualaniensis)产量与表温(SST)及水温垂直结构的关系进行了分析。结果显示,春季是鸢乌贼的高产渔期,总产量及平均网产都明显高于秋季;鸢乌贼作业渔场的季节变化较为明显,春季南沙和西中沙海域都有渔场分布,产量主要集中在10°~15°N、111°~117°E海域内,而秋季鸢乌贼产量主要集中在13°~15°N、117°~118°E海域;鸢乌贼春季和秋季作业渔场的SST范围有所差异,春季作业渔场表温范围为25.6~29.6℃,秋季作业渔场表温范围为27.6~30.0℃,但最适表温都分布于28.5~29.5℃的海域;不同季节作业渔场水温垂直结构差异明显,从5~50 m水温垂直梯度来看,春季鸢乌贼0.00~0.05℃/m组距内平均网产较高,且随着水温垂直梯度的增加而减少;而秋季鸢乌贼平均网产随水温垂直梯度的增加而增加,并于0.15~0.20℃/m组距内达到最高。灰色关联度分析表明,5~50 m水温垂直梯度是对鸢乌贼产量影响最显著的因子,关联度为0.84,纬度、5~100 m水温垂直梯度、表温和经度影响次之。  相似文献   

9.
Temporal variability in abundance and composition of species in marine ecosystems results from a combination of internal processes, external drivers, and stochasticity. One way to explore the temporal variability in an ecosystem is through temporal stability, measured using the inverse of the coefficient of variation for biomass of single species. The effect of temperature and fisheries on the variability of the Barents Sea food web is still poorly understood. To address this question, we simulate the possible dynamics of Barents Sea food web under different temperature and fishery scenarios using a simple food-web model (Non-Deterministic Network Dynamic [NDND]). The NDND model, which is based on chance and necessity (CaN), defines the state space of the ecosystem using its structural constraints (necessity) and explores it stochastically (chance). The effects of temperature and fisheries on stability are explored both separately and combined. The simulation results suggest that increasing temperature has a negative effect on species biomass and increasing fisheries triggers compensatory dynamics of fish species. There is a major intra-scenario variability in temporal stability, while individual scenarios of temperature and fisheries display a weak negative impact and no effect on stability, respectively. However, combined scenarios indicate that fisheries amplify the effects of temperature on stability, while increasing temperature leads to a shift from synergistic to antagonistic effects between these two drivers.  相似文献   

10.
Sea temperature has earlier been shown to have a large influence on the recruitment of Arcto-Norwegian cod, Gadus morhua. We here hypothesize that this linkage is partly due to the direct effect of temperature on larval and juvenile growth. Secondly, temperature acts as a proxy for both biotic and abiotic factors influencing recruitment. Indices of abundance of early juvenile cod (2–3 months old), 0-group cod (4–5 months old) and 3-year-old cod are analysed in more detail against the environmental temperature, wind stress components, wind-induced turbulent energy and the spawning stock biomass. To deal with autocorrelation, non-stationar-time and nun-normality, which complicate a statistical time series analysis, randomization and Box-Jenkins methods are applied. In addition to the important effect of high sea temperature during the early life stage in forming strong year classes, the results show that the spawning stock biomass is nearly as important. Also, alongshore southerly wind stress anomalies during the period of pelagic drift (from April through summer) and offshore wind stress anomalies during egg and early larval stages (in April) act favourably on recruitment. The beneficial effect of southerly wind anomalies could he linked partly to high temperature, but the flux of zooplankton-rich water from the Norwegian Sea into the feeding areas of the Barents Sea may also be increased. The favourable influence of offshore winds in April is less predominant and causal links are also less clear; possible explanations for this might be increased offshore spreading of eggs and early larvae, resulting in reduced risk of predation, and increased compensation inflow of intermediate Norwegian Sea water which, in this restricted period of time, has a high concentration of spawning copepods suitable as prey for the developing cod larvae.  相似文献   

11.
黑潮入侵对南海东北部初级生产力的影响   总被引:1,自引:0,他引:1  
黑潮流经菲律宾东岸时部分水体经吕宋海峡入侵南海东北部。冬季黑潮入侵会明显提高南海东北部的初级生产力, 阐明黑潮入侵对初级生产力的影响将为分析渔业生产力和渔场渔汛提供重要基础。该研究利用1997年~2014年的卫星遥感数据进行分析, 结果表明冬季黑潮入侵明显提升南海北部外海的初级生产力, 其影响范围可达南海北部外海面积的一半; 1997年以来, 南海东北部初级生产力均呈现冬季高而夏季低的特点, 并未出现异常年份; 1997年和1998年受强厄尔尼诺影响, 南海东北部初级生产力明显低于常年, 除此之外, 1999年以来该海域冬季和全年的初级生产力呈显著下降趋势。该研究还根据初级生产力和表层海流的分布和变化情况,判断各年冬季黑潮入侵的主要路径类型。1997年以来的17个冬季, 黑潮流套、黑潮南海分支和黑潮跨越吕宋海峡等3种路径均曾出现, 以南海分支路径为主, 但统计检验表明冬季黑潮以不同路径入侵, 南海东北部的初级生产力并没有显著差异。  相似文献   

12.
根据2006~2009年秋季在东海北部和黄海南部对沙海蜇(Nemopilema nomurai)和温盐度的同步监测数据,对秋季沙海蜇的资源分布特点及其和底层温盐度的关系进行了研究。结果表明:秋季东海北部和黄海南部沙海蜇的高生物分布区主要集中在以下3个海域:(1)南黄海西侧浅水海域;(2)南黄海中央深水区(32°30'N~34°00'N、123°00'E~124°30'E);(3)大沙和长江口外海水域。前2个高生物量分布区某些年份会连成一片,第二个高生物量区基本上每年都会出现,第三个高生物量区某些年份可能不会出现。结合底层温盐度的分布特征,可以看出:沙海蜇高生物量区主要出现在黄海冷水团的前缘或冷暖水团的交汇处,且在冷暖水团的交汇处,更易形成高生物量聚集。而在暖水团控制的海域内,其生物量较低,在垂直分布上,沙海蜇可能主要活动区域在30 m以深的水温相对较低(低于15℃)且变化幅度较小、盐度处于中盐水平(32.0~33.5)的水体内。  相似文献   

13.
水温是影响鱼类活动的重要因素,鱼类繁殖、生长、发育等阶段都对水温有着不同需求。本研究基于2014—2015年4个季节的大面积调查数据,结合R语言绘图技术,采用频率和生物量两种确定温度分布范围的方法,对小黄鱼(Larimichthys polyactis)的水温分布特征进行了分析和比较。研究结果发现:依据频率和生物量分别确定的温度分布范围差别较大;前者覆盖站位比例相对较高,后者覆盖站位累积生物量比例较高;后者在确保生物量累积比例的条件下,某些季节也能有较高的站位覆盖比例,如夏季和秋季;基于生物量确定的温度范围可以更好地反映目标对象的分布特征。与历史研究结果比较,本文的水温分布范围基本保持一致,推断小黄鱼水温分布范围相对稳定,本文研究结果可以反映小黄鱼的一般特征。研究过程中发现小黄鱼有两个群体,水温和空间分布有明显差异;一个群体分布偏北,分布最南水域不超过舟山渔场水域;另一个群体分布偏南,一般分布水域处于长江口渔场以南海域。群体分布环境特征的分离可以作为种群划分的一个依据,本文观察结果可以作为小黄鱼种群划分的一个侧面依据。研究还发现,春、冬冷季小黄鱼资源聚集程度高,而夏、秋暖季资源分布相对分散;冷季群体单一,主要是越冬索饵群体;而暖季群体复杂,包括产卵亲体、补充群体等;暖季出现多个高生物量水温范围,可能与不同群体不同的温度取向相关。  相似文献   

14.
  1. The Atlantic walrus, Odobenus rosmarus rosmarus, forms a herd of nearly 4,000 heads in the Pechora Sea (south-eastern Barents Sea). The Near Threatened status of O. rosmarus rosmarus and the relative isolation of the Pechora Sea population, as well as the potential impacts of human activities in the area, make it important to characterize key habitats, including feeding grounds, in order to protect the species.
  2. The aim of the present study was to integrate multiple sources of environmental and biological data collected by satellite telemetry, remotely operated vehicle (ROV), and benthic grab sampling to examine the distribution and diversity of benthic foraging resources used by walrus in the Pechora Sea.
  3. Analysis of satellite telemetry data from seven males tagged on Vaigach Island helped to identify areas of high use by walruses near haulout sites on Matveev and Vaigach islands, and in between. Field data were collected from those feeding grounds in July 2016 using ROV video recordings and bottom grab sampling. Analysis of 19 grab stations revealed a heterogeneous macrobenthic community of 133 taxa with a mean biomass of 147.11 ± 7.35 g/m2. Bivalve molluscs, particularly Astarte borealis, Astarte montagui, and Ciliatocardium ciliatum, dominated the overall macrobenthic biomass, making up two-thirds of the total.
  4. Analysis of 16 ROV video transects showed high occurrences of mobile benthic decapods (3.03 ± 2.74 ind./min) and provided the first direct evidence that areas actively used by walrus in the Pechora Sea overlap with the distribution of the non-native omnivorous snow crab, Chionoecetes opilio.
  5. Integrating multiple data sources provides an early foundation for the kinds of ecosystem-based approaches needed to improve Pechora Sea resource management and to underpin Russia’s nascent marine spatial planning initiatives. Factors that need to be considered in marine spatial planning include impacts on benthic feeding grounds from offshore oil and gas development and the spread of the snow crab.
  相似文献   

15.
全球变暖等气候变化使渔业资源有向两极移动的趋势,导致渔业生物多样性的变化和生物量随纬度的变化,后者表现为生物量平均温度(mean temperature of the biomass, MTB)的改变。为充分了解黄海渔业资源多样性、生物量及MTB的长期时空动态,本研究基于2000、2009和2018年每年秋季(10月)底拖网调查数据,选择生物量占比超过0.05%的种类作为黄海渔业资源的表征种类,结合海表面温度(sea surface temperature, SST)遥感数据,对黄海鱼类、甲壳类和头足类等重要渔业生物的多样性时空分布及其与SST的关系,生物量及MTB的时空分布进行分析。结果显示,2000、2009和2018年的表征种类分别为39、37和46种。2009年丰度的绝对优势种占比最高,而2000年丰度的绝对优势种占比最低。生物量占比方面,鱼类各年份占比均高于70%,呈先下降后上升的趋势,甲壳类占比由11.45%增至25%以上,头足类占比最小(<1%)且不断下降。在生物多样性指数时空分布方面,Berger-Parker指数和Shannon-Wiener多样性指数的空间分布趋势相反,且未发现经向或纬向的变化趋势;Margalef丰富度指数高值区主要分布在黄海南部海域。SST与生物多样性指数间无显著线性关系(P>0.05)。MTB呈西南高、东北低的趋势,且在34°N附近变化明显,黄海深水区低于近岸;MTB最小值出现在黄海北部,最大值出现在调查海域南端。  相似文献   

16.
Atlantic cod (Gadus morhua) is one of the commercially most important fish species in the North Atlantic and plays a central role in several ecosystems. Fishing pressure has been heavy over a prolonged period and the recent decades have shown dramatic decline in abundance of many stocks. The Arcto‐Norwegian (or North‐east Arctic) cod stock in the Barents Sea is now the largest stock of Atlantic cod. Recruitment to this stock has varied extensively during the last 60 yr. There is evidence for fluctuations in climate, particularly sea temperature, being a main cause for this variability, higher temperatures being favourable for survival throughout the critical early life stages. Our studies of time series present compelling evidence for a strengthening of the climate–cod recruitment link during the last decades. We suggest this is an effect of the age and length composition of the spawning stock having changed distinctly. The age of the average spawner has decreased by more than 3 yr from between 10 and 11 in the late 1940s to 7–8 in the 1990s, average length from just above 90 cm to around 80 cm. The number of age classes contributing to the spawning stock has also decreased, while the number of length groups present increased slightly. Significant decrease in age of spawners has frequently been described for other heavily fished stocks worldwide. We therefore find it likely that the proposed mechanism of increased influence of climate on recruitment through changes in the spawning stock age and size composition is of a general nature and might be found in other systems.  相似文献   

17.
为得到南海及临近海域黄鳍金枪鱼(Thunnus albacores)渔场最适宜栖息海表温度(SST)范围,基于美国国家海洋大气局(NOAA)气候预测中心月平均海表温度(SST)资料,结合中西太平洋渔业委员会(WCPFC)发布的南海及临近海域金枪鱼延绳钓渔业数据,绘制了月平均SST和月平均单位捕捞努力量渔获量(CPUE)的空间叠加图,用于分析南海及临近海域黄鳍金枪鱼渔场CPUE时空分布和SST的关系。结果表明,南海及临近海域黄鳍金枪鱼CPUE在16℃~31℃均有分布。在春季和夏季(3~8月),位于10°~20°N的大部分渔区CPUE较高,其南北侧CPUE较低;而到了秋季和冬季(9月到次年2月),高产渔场区域会向南拓宽。CPUE在各SST区间的散点图呈现出明显的负偏态分布,高CPUE主要集中在26℃~30℃,最高值出现在29℃附近;在22℃~26℃范围内CPUE散点分布较为零散,但在这个范围也会出现相当数量的高CPUE;在22℃以下的CPUE几乎属于低CPUE和零CPUE;零CPUE的平均SST为26.7℃(±3.2℃),低CPUE的平均SST为27.8℃(±2.1℃),高CPUE的平均SST为28.4℃(±1.5℃),高CPUE在各SST区间的分布要比零CPUE和低CPUE更为集中。采用频次分析和经验累积分布函数计算其最适SST范围,得到南海及临近海域黄鳍金枪鱼最适SST为26.9℃~29.4℃。本研究初步得到南海及临近海域黄鳍金枪鱼中心渔场时空分布特征及SST适宜分布区间,可为开展南海及临近海域金枪鱼渔情预报工作提供理论依据和参考。  相似文献   

18.

采用室内封闭静水式呼吸代谢实验装置, 开展不同水温梯度、不同体质量的南海野生真蛸(Octopus vulgaris)的呼吸代谢实验, 分析了不同水温条件下真蛸耗氧率和排氨率的变化, 不同体质量真蛸耗氧率和排氨率的变化, 以及真蛸呼吸代谢底物O:N比的变化。结果表明, 水温变化对南海野生真蛸耗氧率和排氨率有明显影响, 体质量对耗氧率和排氨率的影响不显著(P<0.05)。在16~32℃实验水温范围内, 不同水温梯度下, 相同体质量南海野生真蛸耗氧率及排氨率呈现先升高后降低的趋势; 相同水温条件下, 随着个体体质量的增加, 南海野生真蛸的耗氧率和排氨率虽有缓慢下降但不明显(P>0.05)24℃可能为南海野生真蛸呼吸代谢的转折点, 在该水温下, 其耗氧率和排氨率最高, 代谢速率最快, 单位体质量真蛸的耗氧率和排氨率分别为0.86 mg/(g∙h)36.69 μg/(g∙h)。真蛸呼吸代谢底物分析结果中, 24~28℃水温变化范围内, O:N比不断增加, 表明真蛸呼吸消耗的能量中蛋白质供能比例不断降低。

  相似文献   

19.
Walleye pollock (Gadus chalcogrammus) supports one of the largest commercial fisheries in the world. Juvenile pollock are important forage fish in the eastern Bering Sea (EBS) ecosystem, often representing the largest fraction in the diets of major Bering Sea piscivores. Large variability in the EBS pollock stock biomass in recent years has been attributed primarily to fluctuations in recruitment. It has been hypothesized that predation rates on forage fishes increase when the cold pool (a body of cold water < 2°C) is extensive and covers much of the middle continental shelf, which tends to concentrate larger predatory fishes in the outer shelf and slope regions. In contrast, young pollock appear to tolerate colder temperatures than older fish and can stay in the cold pool, thereby reducing predation. We used a multispecies modeling approach to examine the effects of the cold pool size on predation of juvenile pollock. We found that predation on age‐1 pollock by age‐3+ pollock decreased, and predation on age‐1 and age‐2 pollock by arrowtooth flounder increased with increasing bottom temperature, which was used as a proxy for the cold pool size. These results suggest that the cold pool creates spatial separation between juvenile pollock and arrowtooth flounder, but not between adult and juvenile pollock. The model developed in this study could be used to examine the effects of other covariates on interspecific interactions, help explain observed changes in fish communities, and understand implications of climate change on ecosystems and their productivity.  相似文献   

20.
根据2014—2017年南海北部200m等深线以浅海域渔业资源调查的短尾大眼鲷(Priacanthusmacracanthus)数据,结合遥感获得的海表温度(seasurfacetemperature,SST)数据,首次将渔场水深(D)与SST的乘积(SSTD)引入作为新的变量,采用灰色关联度方法筛选与渔场关联度最高的变量,将关联度最高的变量与标准化后的单位捕捞努力量(catch per unit effect, CPUE)采用一元非线性回归建立模型,对模型理论CPUE与实际CPUE的时空变化进行分析。结果表明,南海北部短尾大眼鲷渔场随季节变化明显,各季节CPUE随SST呈先增大后减小的趋势;不同季节CPUE最高的海域水深不同,春季为160 m,夏季为140 m,秋季为60 m,冬季为140 m; CPUE与SST、D、SSTD进行灰色关联度分析发现,各季节CPUE与SSTD关联度最高且关联度均超过0.5;将SSTD作为变量, CPUE作为表征渔场好坏的指标值,建立环境因子与CPUE的关系模型,模型理论CPUE高值区有明显的季节变化,且实际CPUE高值区的分布与理论CPUE高值区分布一致,以上结果 P值均小于0.05,模型预测准确。  相似文献   

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