Further evidence for the existence of sub‐littoral populations of toheroa,Amphidesma ventricosum Gray (eulamelli‐branchiata), off the west coast of New Zealand     

G. Duncan Waugh  J. P. Greenway 《新西兰海洋与淡水研究杂志》2013,47(4):407-411

The finding of shells of toheroa (Amphidesma ventricosum Gray) which had been drilled by gastropods absent from the littoral zone, is presented as evidence for the existence of sub‐littoral populations of toheroa.  相似文献   

Portable seiche gauge     

E. J. Barnes 《新西兰海洋与淡水研究杂志》2013,47(4):459-465

A portable instrument with a power consumption of less than 1 W has been developed to measure water height at temporary locations. The full scale range of the recorder is 500 mm, and resolution is better than 5 mm water height. Results obtained with the instrument are given, showing seiche activity in a lake.  相似文献   

Oceanic circulation in the head of the Hikurangi trench,east coast,New Zealand   总被引：1，自引：1，他引：0  

R. A. Heath 《新西兰海洋与淡水研究杂志》2013,47(4):651-674

The geostrophic flow and direct current measurements in the inflow of the Southland Current into the Hikurangi Trench east of New Zealand confirm the geostrophic circulation pattern previously found. The northwards inflow of the Southland Current at the latitude of the Chatham Rise (44°S) is estimated at 1.7 × 10⁶ m³.s^‐1, which compares favourably with that of 1.2 × 10⁶ m³.s^‐1 calculated previously off Kaikoura.  相似文献   

Mesh selection studies on flatfish in relation to the Otago trawl fishery   总被引：2，自引：2，他引：0  

G. D. James 《新西兰海洋与淡水研究杂志》2013,47(3):229-240

Cod‐end mesh selection experiments were conducted on three species of flatfish (common or English sole Peltorhamphus novaezeelandiae, lemon sole Pelotretis flavilatus, and sand flounder Rhombosolea plebeia) trawled off the Otago coast. It is suggested that better yields would be obtained from stocks of these fish if the minimum cod‐end mesh size was increased from 10.2 cm (4 in.) to 11.4 cm (4.5 in.).  相似文献   

Lake‐shore spawning of rainbow trout at Lake Rotoma,New Zealand     

B. P. Penlington 《新西兰海洋与淡水研究杂志》2013,47(4):349-355

The presence of suitable gravel size alone can stimulate female rainbow trout (Salmo gairdneri) to excavate nests for spawning on the shores of Lake Rotoma. Emergent fry result from lake‐shore spawning, and could contribute significantly to the trout fishery in Lake Rotoma. Lake‐shore spawning could be enhanced by the use of stable artificial spawning beds that have adequate depth and appropriate sizes of gravel.  相似文献   

Limnology of Lake Rerewhakaaitu     

M. A. Chapman  V. H. Jolly  E. A. Flint 《新西兰海洋与淡水研究杂志》2013,47(2):207-224

The limnology of Lake Rerewhakaaitu (36°18'S, 176° 30'E) was studied at various intervals between 1971 and 1974; comparisons were made between the main lake (area 6.32 km², mean depth 7 m, maximum depth 15 m), and the smaller (0.15 km²) and deeper (mean depth 15 m, maximum 31 m) crater which are connected by a narrow, 1 m deep channel. The main lake was usually homothermal, although temporary stratification periodically occurred, and the oxygen content of the deeper water could be as low as 2 g.m^‐3. The crater showed strong thermal and chemical stratification persisting well into the winter. Its heat budget and other factors related to lake stability are compared with those of some other New Zealand lakes. The failure of the crater to become fully re‐oxygenated during its brief period of homothermy is believed to be related to its morphometry, since the amount of phytoplankton did not appear to be great enough to explain the low levels of dissolved oxygen in the hypolimnion. The hypolimnetic oxygen deficit in 1973–74 was 0.038 mg. cm^‐2.day^‐1. Qualitatively the phytoplankton, usually dominated by desmids, was characteristic of oligotrophic waters, but quantitatively the main lake could be rated as mesotrophic. Differences were also found in the abundance of zooplankton between the crater and the main lake: there were usually more Bosmina but considerably fewer Ceriodaphnia in the main lake which had greater numbers of Piona. Adult Calamoecia were generally more abundant in the crater.  相似文献   

First record of Australian bonito,Sarda Australis,from New Zealand     

G. D. James  G. Habib 《新西兰海洋与淡水研究杂志》2013,47(3):425-426

The range of the Australian bonito, Sarda australis (Macleay, 1880), previously known only from eastern Australia and Norfolk Island, is now extended to include New Zealand. Data on two specimens examined from northern New Zealand are presented.  相似文献   

硫酸钠亚型富锂卤水25℃等温蒸发过程的计算机模拟   总被引：5，自引：0，他引：5  

卜令忠  乜贞  宋彭生 《地质学报》2010,84(11):1708-1714

我国青藏高原上分布有许多盐湖,其中扎布耶等碳酸盐型盐湖、东台吉乃尔等硫酸镁亚型盐湖是著名的富锂盐湖,已成功开发生产出碳酸锂产品。青藏高原上还有许多硫酸钠亚型盐湖,其卤水锂浓度高,钾、镁、硼等有用成分丰富。针对这些盐湖资源,目前尚未进行开发利用研究。这些卤水的等温蒸发实验研究,是必不可少的关键工作之一。本文使用我们由Pitzer电解质溶液理论建立的Li+,Na+,K+,Mg2+/Cl-,SO24--H2O体系的热力学模型,对25℃下几种硫酸钠亚型富锂卤水等温蒸发过程进行了计算机模拟,预测蒸发过程中盐类矿物的析出顺序、卤水组成变化规律、钠、钾、镁、锂盐的饱和点,并在此基础上进行卤水蒸发过程物料平衡关系的理论计算等。本文对西藏3种硫酸钠亚型卤水和国外2种硫酸钠亚型卤水25℃等温蒸发过程进行了模拟。其析盐顺序的特点是:在第一个矿物石盐饱和析出后,接着析出的含钾矿物是钾芒硝,而不是钾镁矾类矿物。其后钾盐则会以钾岩盐形式析出。锂盐饱和后则主要以复盐Li2SO4.K2SO4形式析出。美国银峰卤水的模拟结果与实验蒸发过程完全一致,并给出其继续蒸发时的析盐状况。另4种硫酸钠亚型卤水的模拟结果不仅可以作为未来实验研究的基本参考和注意点,同样也可作为其盐田设计和工艺安排的基本理论依据。本文研究为该类型卤水资源综合开发利用工艺路线的确立提供理论参考。  相似文献   

Criteria for the recognition of acid-precipitated halite     

ELLIOT A. JAGNIECKI  KATHLEEN C. BENISON 《Sedimentology》2010,57(1):273-292

Modern acid and neutral saline lakes in Western Australia are an excellent natural laboratory for testing how pH affects halite, and for developing criteria for distinguishing past acid saline waters from past neutral saline waters in the rock record. This study characterizes and compares physical, chemical and biological features in halite precipitated from acid (pH 1·7 to 4·2) and neutral (pH 6·8 to 7·3) saline lakes in southern Western Australia. Supplemental data include synthetic halite grown from acid and neutral saline solutions, as well as halite deposited in Permian acid lakes. Although physical processes of halite growth are not affected by pH, there are differences in the colour, accessory minerals, fluid inclusions and microfossils between acid and neutral halites. Acid lake halite commonly is yellow or orange in colour; neutral lake halites examined in this study are always snow white. Acid halites tend to contain abundant sulphate and iron oxide minerals, both as solid inclusions and as solids within fluid inclusions; neutral halites contain little, if any, sulphates and no iron oxides. Acid fluid inclusion freezing/melting behaviours include characteristics that differ from neutral fluid inclusion behaviours, such as lower eutectic temperatures, higher and wider temperature range of hydrohalite rims with a definable fuzzy border and more complex metastable phases. Acid halite contains 'hairy blobs', clusters of bacterial/archaeal/fungal remains and sulphate crystals, which are not found in halite from neutral lakes. This distinct assemblage of features characteristic of modern acid lake halites may serve as informal criteria for the recognition of past acid lake evaporites in the rock record.  相似文献   

Late Neogene rift valley fill sediments preserved in caves of the Dead Sea Fault Escarpment (Israel): palaeogeographic and morphotectonic implications     

SORIN LISKER  ROI PORAT  AMOS FRUMKIN 《Sedimentology》2010,57(2):429-445

Evaporitic‐lagoonal marl and dolomite laminar fill sediments are preserved in relict dry caves of the Dead Sea Fault Escarpment (Israel) which has been tectonically active since the Late Neogene. The hosting caves are located within Turonian massive carbonate bedrock and at higher altitudes than previously documented fill sediments of the Dead Sea depression. Based on the relative altitudes of the cave sediments, the ‘reversed stratigraphy’ of the Dead Sea depression fill sediments, possible partial correlation of the cave sediments with other fill sedimentary units of the depression, and sedimentary, geochemical and mineralogical characteristics, it is concluded that: (i) the cave sediments are among the oldest of the depression fill; and (ii) the deposition of the cave sediments took place in hypersaline dolomite‐precipitating water bodies of Late Neogene age, during the initial morphotectonic stages of the depression formation. Variable and relatively low Sr/Ca and δ³⁴S ratios of the cave sediments (assuming precipitation from sea water) suggest variable fresh water input into the depositional brine. The present altitudes of the cave sediments reflect Late Neogene levels of water bodies in the depression, modified by vertical post‐Late Neogene tectonic movements within the still active fault escarpment. According to these altitudes, a 50 to 250 m uplift of the western margins of the depression since the Late Miocene to Early Pliocene is inferred.  相似文献