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分布混合分析的深入研究及其在南极磷虾种群结构中的应用 总被引：1，自引：0，他引：1
介绍分布混合分析的理论，并运用分布混合分析估计南极磷虾种群体长分布概率密度函数的参数，首次给出体长取样间有效性和方差ａ＾２下限的数学分析。概率密度函数式为Ｑ（ｘ）＝ｋ∑ｊ＝１ｐｊｑ（ｘ；ｕｊ，ｑｊ），式中ｘ是随机变量体长的取值；Ｋ是年龄组数；ｐｊ是第Ａｊ年龄组的强度；ｑ（ｘ；ｕｊ，ｑｊ）是均值为ｕｊ；方差为ａ＾２ｊ的正态分布。Ｐｊ，ｕｊ，δｊ，ｊ＝１，２，…，Ｋ是待估计的参数。求解这些参数的最大似 相似文献
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三沙湾浮游植物的分布 总被引：4，自引：2，他引：4
本文分析，鉴定了于１９９０年５，８，１１月和１９９１年２月，采自福建三沙湾的６４份样品。记录浮游植物１１５种，其中蓝藻１种，硅藻９７种，甲藻１７种。浮游植物细胞总量的年平均值为１７．５０×１＾４个／ｍ＾３，其年高峰出现于春季５月。达４３．８４×１０＾４个／ｍ＾３，低谷出现于冬季２月，仅１．１６×１０＾４个／ｍ＾３。 相似文献
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罗氏沼虾育苗用水中Mg2+与Ca2+含量及Mg2+/Ca2+对出苗率的影响 总被引：13，自引：0，他引：13
１９９１年３－６月和１９９２年３－６月在南汇县东海水产养殖公司对罗氏沼虾育苗用水调配原则与不同基础水的调配方法进行试验研究。结果表明，育苗用水中Ｍｇ＾２＋与Ｃａ＾２＋含量及Ｍｇ＾２＋／Ｃａ＾２＋必须达到一定的范围，这是调配的基本原则。以鱼塘水作基础水时，需添加６种化学药品，其中Ｍｇ＾２＋与Ｃａ＾２＋含量可适范围分别为３００．０－４４０．０ｍｇ／Ｌ与１７０．０－２４４．０ｍｇ／Ｌ，Ｍｇ＾２＋／Ｃａ＾ 相似文献
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福建西洋岛海域浮游植物的分布 总被引：2，自引：0，他引：2
鉴定分析了于１９９０年５、８、１１月和１９９２年２月采自福建西洋岛海域的７２份样品。记录浮游植物１２７种，其中蓝藻１种、硅藻１０５种、甲藻２０种、金藻１种。浮游植物月平均细胞总量为５１．４２×１０＾４个／ｍ＾３。其年高峰出现于夏季８月，达１３７．０５×１０＾４个／ｍ＾３，低谷出现在冬季２月，仅有６．９６×１０＾４个／ｍ＾３。 相似文献
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江阴岛海域溶解态Cu,Pb,Cd的含量及其与营养盐的关系 总被引：2，自引：0，他引：2
首次报道了福建省福清市江阴岛海域溶解态Ｃｕ，Ｐｂ，Ｃｄ的含量，并探讨了它们与营养盐的关系。１９９０年５月溶解态Ｃｕ，Ｐｂ，Ｃｄ的平均含量分别为０．８２、０．３８０、０．０２２μｇ／ｄｍ＾２，１０月的平均含量分别为０．７６、０．３８２、０．０３２μｇ／ｄｍ＾２。其５月溶解态Ｃｕ与无机氮Ｎ，硅酸盐间的线性回归相关式分别为Ｃｕ、（μｇ／ｄｍ＾３）＝０．４３８＋０．０３７７Ｎ（μｇ／ｄｍ＾３）、Ｃｕ（μｇ 相似文献
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应用水汽化学的方法学和理论,研究南,北极雪,冰,水中的Ｚｎ＾２＋等离子,南北,极雪,冰,水中Ｚｎ＾２＋,Ｃｄ＾２＋,Ｐｂ＾２＋,Ｃｕ＾２＋,Ｓｎ＾４＋,Ｂｉ＾３＋离子含量的空间变化很小,与水汽化学原理计算的离子总平均含量Ｚｎ＾２＋,５．０μｇ／Ｌ,Ｐｂ＾２＋＋０．０３０μｇ／Ｌ,Ｃｕ＾２＋＋０．７０μｇ／Ｌ,Ｓｎ＾４＋＋０．９９μｇ／Ｌ,Ｂｉ＾３＋＋０．１８μｇ／Ｌ相一致。南北极Ｚｎ＾２＋等离子处 相似文献
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河口水Cu2+, Zn2+的分析、形式、分布、毒性与生态环境 总被引：4，自引：1，他引：4
生物毒性实验Ｃｕ＾２＋，Ｚｎ＾２＋等浓度与生物死亡率相关模式表明，海水中加入的Ｃｕ＾２＋，Ｚｎ＾２＋等浓度逐渐增高，生物死主恨率相应增高，同一浓度下，死亡率随时间（２４，４８，７２，９６ｈ）的增加逐步增高，实验加入Ｃｕ＾２＋仅１μｇ／Ｌ和Ｚｎ＾２＋仅５μｇ／Ｌ本底浓度时，其毒性即已开始遵循相关模式。因此，比天然水含量仅高１，２倍的Ｃｕ＾２＋，Ｚｎ＾２＋离子的污染及毒性，就足以破坏鱼虾在河口的产卵， 相似文献
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沉积物可溶性Ｆｅ＾３＋、Ｆｅ＾２＋含量变化，是反映氧化还原环境的重要指标之一，海洋沉积物Ｆｅ＾３＋／Ｆｅ＾２＋比值已被应用于海洋地质及油气化探上。可溶性亚铁很容易被氧化，为此我们进行了海洋沉积物可溶铁样保存条件的试验研究。试验结果表明，在１０℃以下温度条件保存的海洋沉积物样品其可溶铁Ｆｅ＾３＋／Ｆｅ＾２＋比值在９０天内变化甚微。 相似文献
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Two thousand four hundred and eighty-four specimens from a population of Fundulus heteroclitus introduced into the southwestern Iberian Peninsula were used to carry out a study on age, growth and reproduction. In this new habitat the species displayed the same life-history tactics as in its original areas. The life-span was shorter, with a winter age-structure of 67·4% in 0 + group, 29·1% in 1 + group, 2·5% in 2 + group and 1·1% in 3 + group. Females showed a higher growth rate and a longer growth period than males and because of this they were always longer than males in all the age-groups. In both sexes growth stopped and the somatic condition was at a minimum from April to June, when the gonadosomatic index reached its highest values. The maximum average gonadosomatic index in females was four times higher than that of males. Specimens achieved maturity during the spawning season the year following birth at a minimum average total length of 45 mm for males and 60 mm for females. Fecundity was related to fish weight, total length and gonad weight. The overall sex ratio did not differ significantly from 1:1. 相似文献
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One hundred and seven marine aerosol samples were collected during December 1988 to March 1990, and 3 dry deposition samples, 16 rain samples and 2 Cascade Impacter samples were collected from March to May 1990 at the southeast coast of the Xiamen Island. All the samples were analyzed for SO42-, NO3-, Cl-, Na+ , NH4+, using ion chromatography.The results indicate that the concentration of sulfate in marine aerosols over the Xiamen waters appears to be of seasonal variation, in an order of winter > spring > autumn > summer. The mean sulfate concentration lor the total marine aerosol samples over the Xiamen waters is 9. 37 μg/m3, respectively 0. 89 and 8. 48 μg/m3 for the seasalt and non-sea-salt sulfate. The distribution of sulfate shows a bimodal form with a peak in the coarse particle range which is derived from the sea-salt sulfate, and a peak in the fine particle range which is derived from the non-sea-salt sulfate. The total deposition of sulfate to the Xiamen waters is estimated to be 4. 68g/m2 相似文献
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J. B. Cruz C. Lalas J. B. Jillett J. C. Kitson P. O'B. Lyver M. Imber 《新西兰海洋与淡水研究杂志》2013,47(4):817-829
Prey remains from sooty shearwater (Puffinus griseus Gmelin, 1792) regurgitates, stomachs, and gizzards, were collected from four breeding colonies in southern New Zealand. We found a wide range of prey species (minimum 39 species of 35 genera), the most important of which were crustaceans (particularly euphausiid krill and hyperiid amphipods), cephalopods (notably arrow squid), fishes, and salps. Malacostracans (krill, amphipods, and decapods) were the predominant taxa of prey in both diversity and frequency of occurrence. Regurgitates were easily obtained from harvested chicks and provided the greatest range of prey remains (36 of the 39 species identified). However, these regurgitates comprised only 29% of the total number of samples collected. Fish, malacostracan, and salp prey ranged from 4 to 170 mm in size, whereas total lengths of squid ranged from 50 to 535 mm. Based on size and mass, the largest squid were undoubtedly scavenged, possibly in association with commercial fishers. The geographical distribution of prey species indicate that most sooty shearwaters breeding near Stewart Island forage in waters lying between the Subtropical and Polar Fronts. Our results suggest that the abundance of krill, the impact of fisheries and the influence of climate perturbations on prey species may play important roles in sooty shearwater breeding and survival. 相似文献
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采用MSM寡营养培养基从印度尼西亚Pantai cermin,Kalianda和Banyuwedang三个地区的热泉水样、泥样以及沉积物样品中分离获得细菌菌株,通过检测蛋白酶产生透明圈和福林酚蛋白酶活性测定相结合的方法,从中筛选出1株产嗜热蛋白酶的菌株PBI,该菌株经初步鉴定为短杆菌属(Brevibacillus),并对其酶学性质进行了研究。结果表明,菌株PBI产蛋白酶的最适酶活温度为60℃,最适pH值为8.0～9.0,具有较好的热稳定性和pH稳定性,60℃时酶的半衰期为30min,70℃条件下20min仍保持46.1%的酶活,该酶在pH值为5.0～9.0范围的缓冲液中酶活相对稳定。其产嗜热蛋白酶的酶活力最高可达到60.53U/mL,在100℃条件下仍能保留26.37%的相对酶活。Fe2+,Fe3+,Cu2+和Zn2+对嗜热蛋白酶活性具有明显的抑制作用。该嗜热蛋白酶对EDTA敏感,苯甲基磺酰氟(PMSF)、亮抑酶肽(Leupeptin)、苄眯(Benzamidine)和胃蛋白酶抑制剂(Pepstain A)对该嗜热蛋白酶都有一定的抑制作用,说明其酶活性受到丝氨酸、半胱氨酸残基的影响。结果表明,该菌株是1株具有进一步改造利用价值的产蛋白酶菌株。 相似文献
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Some aspects of the biology of the micronektonic fishesCyclothone pallida andC. acclinidens are described on the basis of samples taken during a series of 20 cruises from December 1982 to November 1985 at a fixed station near the center of Sagami Bay, Central Japan.C. pallida is a regular component of theCyclothone population in Sagami Bay, being found in more than 90% of the samples. On the other hand,C. acclinidens was encountered sporadically, being found in less than 25% of the samples. The depth range ofC. pallida is estimated to be about 400–1,000 m. It spawns mainly during the spring and summer in Sagami Bay.C. pallida releases about 1,000–3,000 eggs and may spawn several times during its life span. On the average, it reaches 18.5 mm standard length (SL) in one year, 24 mm SL in two years and 29.5 mm SL in three years during its subadult stage. Extrapolation of the growth curve suggests that males and females attain first sexual maturity in three to four years at 30–35 mm and five to six years at 40–45 mm SL, respectively.Cyclothone pallida is concluded to have a regular life cycle in Sagami Bay. It remains uncertain whether or notC. acclinidens reproduces in this area. 相似文献
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对具有高淀粉酶活性的南极菌Pseudoalteromonas sp. A211-5的全基因组数据进行了分析和筛选,筛选获得α-淀粉酶疑似序列amy3809,并采用基因工程手段对该基因的功能和性质进行验证和分析。首先,以淀粉酶Amy3809的完整开放阅读框(ORF)为模板设计特异引物,克隆获得amy3809的全序列并对其进行重组表达,获得的重组蛋白采用镍柱进行分离纯化;DNS-还原糖法测定重组酶的酶学性质;薄层层析(TLC)技术对Amy3809的酶解产物进行分析。实验结果:1)克隆获得的amy3809成功地连接到pET-30a载体,并在工程菌E.coli BL21(DE3)中实现了高效表达,纯化的重组酶Amy3809分子量为67 kDa;2)重组酶Amy3809在10~40℃的范围内仍能保持85%以上的酶活,但随着温度的升高酶活迅速降低,70℃时几乎失活,表明该酶具有良好的低温耐受特性及热敏感性;3)最适pH为7.0,在pH 5.0~10.0的范围内仍能保持50%以上的活性;4)金属离子Na+,K+和Ca2+均能提高Amy3809的活性,而Cu2+,Fe2+,Mg2+和EDTA则能显著降低Amy3809的活性;5)Amy3809的酶解产物主要为麦芽四糖、麦芽三糖、麦芽糖和葡萄糖。由此可知,南极菌产的α-淀粉酶Amy3809,具有良好的低温耐受特性,热敏感性和较广的pH耐受范围,并能够有效地将淀粉降解为低聚糖和葡萄糖,因而具有潜在的工业应用前景。 相似文献
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在 １９９２～１９９３年度南极夏季期间，用肠道荧光法现场测定大磷虾（Ｅｕ－ ｐｈａｕｓｉａ ｓｕｐｅｒｂａ Ｄａｎａ）的肠道排空率和肠道内含物色素水平，并据此计算自然状况下 大磷虾的摄食率。大磷虾的肠道排空率为０．４３／ｈ。次成体（平均体重为１６８．８ｍｇ干 重）和成体（平均体重为 ２７４．３ｍｇ干重）的摄食率分别为 １８０．６±１９．２和 ４６４．４± ２８．３ｎｇ叶绿素ａ／ｈ。自然状况下大磷虾的摄食率与现场测定的 １００ｍ以上水层平均 叶绿素ａ浓度的相关性不大。 相似文献