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以皱纹盘鲍(Haliotis discus hannai Ino)中国群体与日本群体的杂交(WJ)子1代为母本,在汕头养殖并选育了3代的“S”群体为父本,建立三元杂交组合(WJ-S)并尝试了海区围堰全生态模式养殖。以同期繁育的皱纹盘鲍中国群体与日本群体的杂交子1代(WJ-F1)为对照,比较 WJ-S 与对照组在生长速度和存活率等方面的差异。结果表明,在苗种和养成阶段, WJ-S 的度夏存活率均显著高于同期对照;从围口壳幼体到养成阶段, WJ-S组的平均壳长大于同期对照,养成阶段WJ-S组的全湿重显著高于对照,表明皱纹盘鲍三元杂交子代的生长速度显著高于对照;从苗种到养成阶段的3次分选数据表明, WJ-S的大规格子代比例均高于对照,小规格苗种比率则低于对照,表明三元杂交鲍苗种的生长速度优于对照;在青岛崂山海区全生态养殖18个月,三元杂交组已达商品规格。上述结果表明,在二元杂交的基础上加入第三方亲本 S 制备的三元杂交皱纹盘鲍,在生长速度、夏季高水温期的存活率等方面都较皱纹盘鲍“中-日”杂交子代显著提高。 相似文献
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九孔鲍的人工苗种生产技术 总被引：9，自引：0，他引：9
九孔鲍Ｈａｌｉｏｔｉｓｄｉｖｅｒｓｉｃｏｌｏｒａｑｕａｔｉｌｉｓ自１９９０年从台湾省首次引进在福建东山岛养殖以来 ,迅速发展 ,现在已成为福建闽南地区以南沿海养殖的主要鲍种。该鲍具生长快 ,适合本地区养殖的特点 ,从２．０ｃｍ左右鲍苗装笼，经过６个月养成 ,就可以达到５．５ｃｍ商品规格。根据多年来从事九孔鲍人工苗种生产技术的研究和实践经验 ,本文就九孔鲍苗种生产环节中的若干技术问题 ,作一介绍。１亲鲍性腺促熟九孔鲍的自然繁殖季节在福建闽南地区是８～１０月份 ,但在此之前的４～７月份 ,也可看到少数成鲍性腺成熟。在… 相似文献
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研制了4种不同规格的T型标志牌(T-A,T-B,TC,T-D),对不同规格的半滑舌鳎苗种进行了标记试验,记录了标记后的脱牌率、成活率、行为特征和生长情况,筛选了适宜于半滑舌鳎苗种标志放流的T型标志牌.结果表明:T-A标志牌适宜于标记全长8 cm以上的苗种,标记后的实验鱼生长与对照组无显著差异,标志后暂养成活率92％～100％;T-B标志牌适宜标记全长16 cm的苗种,标记后实验鱼成活率达到100％,脱牌率为0.T-C和T-D标志牌不适宜于标记全长16 cm以下的半滑舌鳎苗种.2011年,利用本研究开发的T-A标志牌标记半滑舌鳎苗种,并在莱州开展大规模标志放流试验,标记效果良好. 相似文献
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牙鲆（Ｐａｒａｌｉｃｈｔｈｙｓ ｏｌｉｖａｃｅｕｓ）的常温育苗已有过一些报道［１～３］。为了提高牙鲆苗种规格，增强苗种度夏能力，缩短养殖周期，１９９５年我们在荣成市马山渔业公司育苗场进行了牙鲆升温育苗生产。截至７月６日巳育出全长５～１０ｃｍ大规格牙鲆亩种３０００００尾，至自然水温达到最高值的８月下旬，部分鱼种全长已达１５ｃｍ以上，大大增强了苗种度更能力，提高了苗种度夏成活率。１亲鱼培育及产卵１．１亲鱼培育１９９６年第５期于１９９４年１１月份购入海上捕捞的牙鲆亲鱼３３尾，全长范围４０～７５ｃｍ，体… 相似文献
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“大菱鲆引进驯化和养殖”的试验 总被引：4，自引：0，他引：4
为增加福建省的养殖新品种，作者于1997年和1999年先后两批从山东省威海市引进全长3－5cm的大菱鲆鱼，在室内池进行驯养试验，养殖试验结果表明，大菱鲆生长快，11月龄的大菱鲆体重最小为350g，最大达1250克，平均为797克；大菱鲆在室内养殖可在安全渡夏，试验还发现，‘紫萁”可作为大菱鲆的促长剂，另外，全长6－10厘米， 重10－30克的大菱鲆鱼，经5个月海水网箱养殖，平均体重可达400克左右，这些结果可为大菱鲆工厂化养殖和海水网箱养殖提供科学依据。 相似文献
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本研究采取苗种强化培育、坑道培育大规格苗种、湖间带鲍参混养等相结合,并配套适当技术措施,促进鲍快速生长,缩短养殖周期一年左右,提高成活率15％以上,增加经济效益200％左右,形成鲍高效养殖的较理想模式。 相似文献
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Tautog, Tautoga onitis, is an abundant species of fish in estuaries of the northeastern United States. Planktonic tautog larvae are abundant in summer in these estuaries, but there is little information on rates of growth of tautog larvae feeding on natural assemblages of food in the plankton. We examined abundance and growth of larval tautog and environmental factors during weekly sampling at three sites along a nearshore‐to‐offshore transect in Buzzards Bay, Massachusetts, USA during summer 1994. This is the first study of a robust sample size (336 larvae) to estimate growth rates of field‐caught planktonic tautog larvae feeding on natural diets, using the otolith daily‐growth‐increment method. The study was over the entire summer period when tautog larvae were in the plankton. The sampling sites contrasted in several environmental variables including temperature, dissolved oxygen (DO), and chlorophyll a concentration. There was a temporal progression in the abundance of tautog larvae over the summer, in relation to location and temperature. Tautog larvae were first present nearshore, with a pronounced peak in abundance occurring at the nearshore sites during the last 2 weeks in June. Larvae were absent at this time further offshore. From late June through August, larval abundance progressively decreased nearshore, but increased offshore although never approaching the abundance levels observed at the nearshore sites. The distribution and abundance of tautog larvae appeared to be related to a nearshore‐to‐offshore seasonal warming trend and a nearshore decrease in DO. Otoliths from 336 larvae ranging from 2.3 to 7.7 mm standard length had otolith increment counts ranging from 0 to 19 increments. Growth of larval tautog was estimated at 0.23 mm·day?1, and length of larvae prior to first increment formation was estimated at 2.8 mm indicating that first increment formation occurs 3–4 days after hatching at 2.2 mm. Despite spatial and temporal differences in environmental factors, there were no significant differences in growth rates at any of three given sites over time, or between sites. Because larval presence only occurred at a narrow range of temperature (17–23.5 °C) and DO (6.5–9.3 mg·l?1), in situ differences in growth did not appear to be because of differences in larval distribution and abundance patterns relative to these parameters. 相似文献
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Soil-sized particulates have been collected on board ship by a mesh technique from the lower troposphere of the North, Equatorial and South Atlantic Ocean, northern and southern Indian Ocean, South and East China Sea and various coastal localities.Spectrographic analysis reveals that, on average, the particulates have concentrations of Mn, Ni, Co, Ga, Cr, V, Ba, and Sr which are of the same order of magnitude as those in average crustal material. In contrast, the average concentrations of Pb, Sn, and Zn are one order of magnitude higher than those in average crustal material.Within this “world-wide” average there are significant geographical variations in the distributions of Pb, Sn, and Zn which may be related to anthropogenic sources.On the basis of trace-element distributions lower tropospheric soil-sized marine particulates have been divided into four genetic components; local, zonal, inter-zonal, and global. The proportions of these components vary geographically, and each component may have both a natural and an anthropogenic fraction. 相似文献
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Klaus Kremling 《Marine Chemistry》1983,13(2):87-108
In June 1981, dissolved Zn, Cd, Cu, Ni, Co, Fe, and Mn were determined from two detailed profiles in anoxic Baltic waters (with extra data for Fe and Mn from August 1979). Dramatic changes across the O2H2S interface occur in the abundances of Cu, Co, Fe, and Mn (by factors of ?100). The concentrations of Zn, Cd, and Ni at the redox front decrease by factors between 3 to 5.Equilibrium calculations are presented for varying concentrations of hydrogen sulfide and compared with the field data. The study strongly supports the assumption that the solubility of Zn, Cd, Cu, and Ni is greatly enhanced and controlled by the formation of bisulfide and(or) polysulfide complexes. Differences between predicted and measured concentrations of these elements are mainly evident at lower ΣH2S concentrations.Cobalt proved to be very mobile in anoxic regions, and the results indicate that the concentrations are limited by CoS precipitation. The iron (Fe2+) and manganese (Mn2+) distribution in sulfide-containing waters is controlled by total flux from sediment-water interfaces rather than by equilibrium concentrations of their solid phases (FeS and MnCO3). The concentrations of these metals are therefore expected to increase with prolonged stagnation periods in the basin. 相似文献
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Izvestiya, Atmospheric and Oceanic Physics - Data on the relative contribution of the Ox, HOx, NOx, ClOx, BrOx, and IOx catalytic cycles to atmospheric ozone destruction are given for June and... 相似文献
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Maryd De Wemton John S. Clayton Rohan D. S. Wells Chris C. Tanner Suzanne T. Miller 《新西兰海洋与淡水研究杂志》2013,47(2):145-151
The submerged vegetation of Lakes Sumner, Marion, Katrine, Taylor, and Sheppard was surveyed in May 1987. These high‐altitude lakes lie at c. 600 m a.s.l., within the largely unmodified upper Hurunui catchment. Submerged vegetation was diverse and included numerous short shallow‐water species, dense swards of Isoetes alpinus, low covers of taller native vascular plants, and charophyte meadows beyond the depth limit of vascular plants to a maximum of 15 m. A sparse deepwater bryophyte community was observed from 11 to 32 m depth in Lake Sumner. Displacement of native vegetation by dense growths of the adventive oxygen weed Elodea canadensis over mid‐depths of 3–6 m was noted in all lakes, except Lake Marion. 相似文献
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Linjie Zheng Tomoharu Minami Shotaro Takano Hideki Minami Yoshiki Sohrin 《Journal of Oceanography》2017,73(5):669-685
A central theme of the ongoing GEOTRACES program is to improve the understanding of processes occurring at ocean interfaces with continents, sediments, and ocean crust. In this context, we studied the distributions of Al, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb around the Juan de Fuca Ridge (JdFR) in total dissolvable (td), dissolved (d), and labile particulate (lp) fractions, which represent a fraction in unfiltered samples, filtered samples through an AcroPak capsule filter, and the difference between td and d, respectively. Al and Fe were dominated by lp-species, while Ni, Zn, and Cd were dominated by d-species with undetectable amounts of lp-species. Major findings in this study are as follows: (1) The continental margin (CM) provided large sources of Al, Mn, Fe, and Co from the surface to ~2000 m in depth. The supply from CM caused high surface concentrations of dMn and dCo, a subsurface (100–300 m depth) maximum of dCo, and intermediate (500–2000 m depth) maxima of lpAl and lpFe. The supply of dFe from CM was ~10 times that from the high-temperature hydrothermal activity at station BD21, which is located at ~3 km from the Middle Valley venting site and ~ 200 km from Vancouver Island. (2) DPb was maximum at the top layer of North Pacific Intermediate Water, probably owing to isopycnal transport of anthropogenic Pb via advection of subducted surface waters. Although dCo and dPb had different sources in the upper water, they showed a strong linearity below 300 m (r 2 = 0.95, n = 38), indicating concurrent scavenging. (3) A high-temperature hydrothermal plume occurred at a depth of 2300 m at BD21, accounting for maxima of dAl, dMn, dFe, lpCu, and lpPb and a minimum of dCu. (4) Strong bottom maxima of lpAl, lpMn, lpFe, lpCo, and lpPb occurred above the abyssal plain at the western foot of the JdFR, indicating resuspension of sediments. However, bottom maxima of d-species were apparent only for dAl and dCu. 相似文献
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While clastic mudstones and shale were traditionally interpreted to have been deposited in quiet water settings, recent flume experiments and studies have shown that mud can be transported in and deposited by traction currents as migrating ripples of mud aggregates. Despite these recent advances, mud aggregates have rarely been adequately described in the rock record.These mud aggregates and the sedimentary structures they form in mudstone successions are difficult to observe in the rock record due to compaction, which often obliterates the aggregates and flattens bedforms. This paper documents unambiguously identifiable sand sized mudstone aggregates in thin sections and SEM, transported in traction, and deposited in a series of prograding clinothems. These aggregates were sufficiently indurated to locally preserve shelter porosity, significantly improving the hydrocarbon reservoir properties.Grain size analysis of the aggregates was performed on thin sections, as well as disaggregated samples measured by a laser diffraction grain size analyzer for comparison. These analyses showed that sand sized aggregates often comprise more than half of the sediment volume. While the clay-rich composition of the Carlile Formation would suggest that it is a mudstone, statistical analysis of these grain size measurements show that it could alternatively be described as a silty sandstone. These findings potentially change how we think about mudstone classification, fine-grained sedimentation, and mudstone dominated petroleum reservoirs. 相似文献
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The radiometers on board the satellites ERS-1, TOPEX/Poseidon, ERS-2, GFO, Jason-1, and Envisat measure brightness temperatures at two or three different frequencies to determine the total columnal water vapor content and wet tropospheric path delay, a major correction to the altimeter range measurements. In order to asses the long-term stability of the path delay, the radiometers are calibrated against vicarious cold and hot references, against each other, and against several atmospheric models. Four of these radiometers exhibit significant drifts in at least one of the channels, resulting in yet unmodeled errors in path delay of up to 1 mm/year, thus limiting the accuracy at which global sea level rise can be inferred from the altimeter range measurements. 相似文献