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11.
本文依据 1 989/ 1 990和 1 990 / 1 991南极夏季在普里兹湾邻近海域所获取的拖网样品 ,对大磷虾 (Euphausia superba Dana)的种群结构进行了分析。体长频数分布表明 ,种群中主要包括4个年龄组 ,即 1 + 、2 + 、3 + 、和 4+ 龄。 5 + 和 5龄以上的高龄组所含比重很小 (<3 %)。雌性临产个体 (3 DF)的体长频数分布表明 ,大磷虾的初次性成熟年龄为 3龄。生殖群体也以 3 +龄为主 ,4+龄次之。种群组成存在着明显的地区差异。普里兹湾以北海域是典型的双态分布 ,1 + 龄占有相当大比重 ;测区东西两侧以成体虾为主 ,极少有 1 + 龄虾。种群组成的年际变化也是明显的 ,特别表现在补充群体 (1 + 龄 )的强度上 相似文献
12.
胶州湾的初级生产力和新生产力 总被引：2，自引：0，他引：2
海洋初级生产力是海洋食物链的基础,是进行海洋生物资源评估和合理开发利用的基本依据。70年代在国际生物圈计刘(IBP)的推动下,本领域的一些学者曾在世界各大洋的代表性海区进行过大量现场观测研究。最近,随着世界性的资源与环境问題的日趋严重,全球C循环已成为人们关注的研究课题。海洋初级生产力是了解全球C循环必不可少的指标之一,因而再度成为生物海洋学家的研究对象。新生产力是总初级生产力的一部分,亦是海洋N循环的特征参数,对于大洋水域而言,它反映了真光层生物群落的净生产力,代表了真光层向下输出的C通量,是当今有关国际研究计划,如全球海洋通量联合研究( JGOFS)的核心内容之一。初级生产力和新生产力的研究,对于海洋生物资源的持续利用和C、N生物地球化学循环具有十分重要的意义。
胶州湾作为我国温带地区的典型海湾,已成为我国生态研究系统网络(CERN)的野外观测站。代表性的地理位置和强度开发下的生态条件,使其生态学资料在环境监测和资源开发方面极具理论意义和应用价值。胶州湾的初级生产力曾用黑白瓶生氧量法测定过(郭玉洁等,1992),而新生产力的实测研究在国内尚属空白。本文运用14C,15N同位素示踪方法,在胶州湾进行了季节性的初级生产力和新生产力现场实验研究,获得了比较系统的观测资料。 相似文献
13.
黄海小拟哲水蚤(Paracalanus parvus)丰度的季节变化 总被引：1，自引：0，他引：1
根据2001年3、5、6、7、8、11月黄海6个航次的大容量采水器(59L)中浮游动物的样品资料,对小拟哲水蚤无节幼体及该种桡足幼体和成体丰度的时空分布格局进行了研究。结果表明,小拟哲水蚤桡足幼体和成体3月份在整个黄海测区内的丰度较低;5月份除山东半岛南岸三个高值站位,外海相对比近岸高;6、7月份的丰度水平最高,7月份航次中,丰度最高的站位可达10555ind/m3,整个测区内,海州湾内侧高于外侧;8月份,测区内的丰度分布相对均匀,丰度较低;11月份,测区小拟哲水蚤的分布相对也比较均匀。小拟哲水蚤无节幼体的丰度在黄海测区内的分布格局与该种桡足幼体及成体丰度的分布格局在3、5、6、7月份比较吻合,在8、11月份吻合程度较差。不同月份小拟哲水蚤的分布与温度、盐度、叶绿素a的关系不尽相同;其受温度的影响相对较大,受盐度、叶绿素a影响较小。 相似文献
14.
Antarctic krill (Euphausia superba) were collected from the Prydz Bay region during the austral summer of 1999/2000. The sample - collection was made at 15 sites in 3 longitudinal transects. Although krill were encountered at 14 sites, the abundance was comparatively low in general. The main component of the krill population was of post -larval stages. The mean numerical and weight density of krill integrated for all sampling stations in the survey area were 16. 17 ind. 1000 m -3and 12.02 g 1000 m -3 , respectively. In the survey area, stations with larger krill density are mainly located in the slope zone, except that the largest sample was collected in the open sea zone. No krill occurred in the only station of the shelf zone during our investigation. Krill collected from the slope zone were under better growth condition than those from the open sea zone, but when the survey area is considered as a whole, the growth condition is normal. The results of the comprehensive analysis of the environmental fa 相似文献
15.
Metabolic rates (oxygen consumption and ammonia excretion) of two dominant copepods, Calanoides acutus and Metridia gerlachei, were measured during the austral summer (December 1998 January 1999), in the marginal ice zone of the Prydz Bay. Their elemental compositions (C and N) were also analysed through these metabolic experiments. The results showed that C. acutus was 48.4% 48.6% of dry weight in carbon content and 6.1% 6.5% of dry weight in nitrogen content. Metridia gerlachei was 47.1% 50.1% and 5.9% 7.4%, relatively. Oxygen consumption rates of C. acutus were variant in the different areas (0.226 to 0.774 μlO2mg-1h-1). And its ammonia excretion rates ranged from 0.014 to 0.105 μgNmg-1h-1. The ratio between the rates (O∶N) exhibited a large difference(5 6 times). For Metridia gerlachei, oxygen consumption rates were 0.488 0.644 μlO2mg-1 and ammonia excretion rates were 0.015 0.034 μgNmg-1h-1. From the results of metabolic rate measurements and elemental analyses, daily losses of body carbon and nitrogen were estimated to be 0.59% 1.99% and 0.44% 3.27%, respectively. The metabolic carbon requirements accounted for 0.6% 29.2% of primary production per day, and their excretion of ammonia occupied 0.2% 38.0% of daily phytoplankton nitrogen demand. 相似文献
16.
于 1 998年 1 2月至 1 999年 1月南极夏季 ,对南大洋普里兹湾临近海域主要被囊类纽鳃樽的数量密度分布进行了现场调查 ,同时于 - 3站对纽鳃樽对浮游植物的摄食率利用肠道色索法和颗粒递减法进行了现场研究。调查结果表明 ,纽鳃樽主要分布于调查海区的浮冰区北部边缘及其以北的开阔水域。在密集区其数量密度高达 2 795ind..1 0 0 0 m- 3,浮冰区几乎没有发现。 - 3站现场摄食实验结果显示 ,纽鳃樽个体肠道色素含量变化范围为 0 .1 4～ 1 .2 7μg.ind.- 1,平均为0 .98μg.ind.- 1。肠道色素法测得的纽鳃樽对浮游植物的摄食率为 7.9μg.ind.- 1d- 1,滤水率为2 81 ind.- 1d- 1。颗粒递减法测得纽鳃樽滤水率为 1 5.3± 4.61 ind.- 1d- 1,比肠道色素法所得结果偏低。虽然由此推算纽鳃樽群体的日摄食量只占浮游植物现存量的 0 .8% ,但是对于初级生产力却有一定的摄食压力 ( 72 .2 % )。 相似文献
17.
于 1 998年 1 2月至 1 999年 1月南极夏季 ,对南大洋普里兹湾临近海域两种主要浮游桡足类Calanoides acutus和 Metridia gerlachei的耗氧率和排氨率进行了现场调查 ,同时对其代谢产物对海洋初级生产的贡献进行了探讨。调查结果表明 ,C. acutus的体碳、氮含量占干重百分比分别为 48.4%～ 48.6%和 6.1 %～ 6.5% ;M.gerlachei分别为 47.1 %～ 50 .1 %和 5.9%～ 7.4%。C.acutus在不同海区耗氧率有一定的差异 (0 .2 2 6～ 0 .558μl O2 mg- 1h- 1)。排氨率变化范围为 0 .0 1 4～ 1 .0 58μg N mg- 1h- 1,最高值位于浮冰区 - 9站 ,在陆冰缘区 (FI站 )最小。不同海域其排氨率的高低与现场水温无相关性。不同站位上 C.acutus的 O:N比相差 5～ 6倍。M.gerlachei耗氧率为 0 .488～ 0 .644μl O2 mg- 1h- 1,排氨率为 0 .0 1 5～ 0 .0 34μg N mg- 1h- 1。根据代谢实验结果和桡足类自身碳氮含量推算 ,其维持正常代谢的碳、氮日损失率分别为 0 .59%～ 1 .99%和 0 .44%～ 3.2 7%。桡足类群体每天的碳需求量占初级生产力的 0 .6%～ 2 9.2 % ,氨氮日输出量占初级生产所需氮盐的 0 .2 %～ 38.0 %。 相似文献
18.
南极普里兹湾边缘浮冰区微型浮游动物的摄食及其氮的排泄 总被引：14，自引：1，他引：13
于1998–1999年夏季在南极普里兹湾边缘浮冰区利用稀释培养实验进行了微型浮游动物对浮游植物的摄食现场实验研究,同时对微型浮游动物的氨氮产生率进行了推算。结果表明,微型浮游动物的日摄食量为5.1–25.0mgC/(m3*d),占浮游植物现存量的10%–65%,对初级生产力的摄食压力也较大(34%–100%)。利用微型浮游动物的摄食率推算得出其氮产生率为0.44–1.75mg/(m3*d),达到维持现场初级生产所需氨氮的68%–536%。由此可见,微型浮游动物在南极夏季边缘浮冰区海洋生态系统中,特别是对浮游植物的生产和归宿起着十分重要的调控作用。 相似文献
19.
Calanus sinicus is a calanoid copepod widely distributed in coastal waters of China and Japan, and oversummering strategies may have major impacts on their population dynamics which in turn affect local marine food web structure. The abundance, stage composition, and sex composition of the planktonic copepod C. sinicus were studied from August to October 2002 in the southern Yellow Sea to understand how its population recovers from the over-summering state. Results showed that C. sinicus had low reproduction in August due to high temperature, except in waters near the Cheju Island with rich food and moderate bottom temperature, but the reproduction rates here decreased in September–October as food availability declined. When temperature dropped in September–October, C. sinicus actively propagated in coastal shallow waters. However, reproduction rates of C. sinicus individuals inhabiting the Yellow Sea Cold Water Mass(YSCWM) remained low during the three months of the study. The percentage of C. sinicus females was high during the reproductive period, which suggests that the sex composition of adult C. sinicus may reflect whether or not the population is in the reproductive mode.Numerous fifth copepodite stage(CV) C. sinicus aggregated in the YSCWM in a suspended developmental stage during the three months of this study, and they potentially served as the parental individuals for population development when conditions became optimal for reproduction later in the year. 相似文献