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941.
青藏高原热力异常与华北汛期降水关系的研究   总被引:24,自引:3,他引:24  
利用1980~1994年NCEP/NCAR再分析资料,以及我国336个测站1956~1994年月降水量资料,通过诊断分析和数值实验,研究了夏季高原上热力异常与华北汛期降水的关系.结果表明:华北汛期干旱年,青藏高压及西太平洋副热带高压偏南、偏东,华北汛期降水偏多年则相反;华北汛期旱年时,高原上升、高原东侧邻近地区下沉的垂直环流明显加强,而降水偏多年时,垂直环流减弱,华北地区为上升气流控制;夏季高原为热源和水汽汇区,它们的异常对华北地区降水有很大影响,当热源和水汽汇增强(减弱)时,华北地区降水偏少(偏多).数值试验表明,高原上潜热加热异常引起青藏高压、西太平洋副热带高压、亚洲季风以及欧亚中高纬地区环流的变化,进而影响到华北地区的降水.  相似文献   
942.
The grazing turbinid gastropod Lunella smaragda was sampled regularly over 3.5 y from precise sites of different microtopography and height on the platform shore at Goat Island Beach near Leigh, Northland, New Zealand. Growth is linear for over 3 y, and the year‐classes distinct. The position of the different size‐classes is related to both the shelter afforded by the microtopography, and to the height on the shore. The populations in the mid‐eulittoral turf flats, low eulittoral bare rock areas, and the sublittoral fringe are distinct, and there is a general movement down the shore with age and size. Wave action apparently dislodges the animals from higher areas when they grow to a critical size and transports them to sites lower on the shore, where wave disturbance is less. Field experiments with marked animals and laboratory studies with a wave tank confirm that the wave‐effected distribution is size related. However measurements showed that the ratio of foot attachment area to the shell area presented to the wave does not vary with animal size. The possible benefits of wave dislodgment and wave‐effected distribution are considered.  相似文献   
943.
The discovery at Stewart Island of a hauling‐out ground regularly used by Hooker's sea lions (Phocarctos hooked) is described, and recent sightings of sea lions in southern New Zealand are reported. An attempted copulation between a male Hooker's sea lion and a dead female fur seal (Arctocephalus forsteri) is also described.  相似文献   
944.
The distribution of 376 salmon caught at sea between 41 °S and 46 °S up to 48 km off the east coast of the South Island between 1925 and 1978 is discussed. The distribution appears to be related to strong currents in Cook and Foveaux Straits, and to the Southland Current off the east coast of the South Island. Samples from the sea at Moeraki Peninsula had a higher incidence of stream‐reared fish and a lower mean fork length than samples from the Waitaki or Rakaia Rivers at spawning.  相似文献   
945.
Frostfish spawning, as indicated by the presence of planktonic eggs, was observed mainly in north‐eastern, but also in south‐western, New Zealand waters in spring to autumn. Spawning takes place in the afternoon in outer shelf waters 50–200 m deep, with surface temperatures and salinities between 17.5 and 22.0°C and 35.3 and 35.6‰ respectively. Egg and oil droplet diameters ranged from 1.65 to 1.75 mm and 0.40 to 0.43 mm respectively.  相似文献   
946.
To establish a base line against which future pollution may be measured, eight common commercial species of New Zealand sea fish were analysed for cadmium, chromium, copper, iron, lead, manganese, nickel, and zinc. One sample of edible muscle tissue was analysed for each of 70 samples of each species. The internal organs of up to five specimens of each species were also analysed. The fish studied were: kahawai, Arripis trutta, trevally, Caranx lutescens, tarakihi, Cheilodactylis macropterus, snapper, Chrysophrys auratus, moki, Latridopsis ciliaris, hapuku, Polyprion oxygeneios, kingfish, Seriola grandis and gurnard, Trigla kumu.

Although, none of the edible parts of the fish appeared to have trace element levels likely to be a public health problem (cadmium 0.002–0.02 ppm, chromium 0.01–0.04 ppm, copper 0.04–0.95 ppm, iron 0.9–13.5 ppm, lead ‘ 0.14–0.95 ppm, manganese 0.04–2.00 ppm, nickel 0.01–0.08 ppm, zinc 2.0–36.0 ppm), some of the organs (particularly the liver) had relatively high concentrations of elements such as cadmium (up to 54 ppm). Only if some industry were to seek to exploit internal organs of fish for human consumption would such levels become important. There was some evidence for a relationship between trace element concentrations and fish size for copper in kingfish and snapper, iron in hapuku, manganese in gurnard, and for zinc in kingfish and tarakihi. Some element pairs such as copper and zinc, iron and manganese, appeared to have concentrations which were mutually related. It was assumed that the elemental concentrations reported represent natural levels and are not the result of significant man‐made pollution because there are no major industries or large urban centres adjacent to the fishing grounds.  相似文献   
947.
From a trawling at 448–512 m in Palliser Bay, Cook Strait, New Zealand, molluscs associated with. Tertiary siltstone concretions and with a large colony of Goniocorella dumosa (Alcock) are listed. A juvenile Acesta, extremely tall and extremely broad forms of Emarginula striatula Quoy & Gaimard, and the animals of Stilifer neozelanica Dell and of Waipaoa marwicki Dell are described. Sculptifer, a new genus provisionally included in the Fossaridae, is proposed for Stilifer neozelanica. New species of Danilia and Pholadidea are described and their relationships discussed. Emarginula lophelia Beu, 1967 is synonymized with E. striatula Quoy & Gaimard, 1834, and the recent New Zealand forms of Emarginula are reviewed.  相似文献   
948.
杭州湾海域春、秋季鱼类种类组成和数量分布   总被引:8,自引:0,他引:8  
采用底层拖网法,用渔获率作为鱼类资源数量分布的指标,进行了杭州湾调查海域2012年5月(春季)、10月(秋季)2个季节的鱼类种类组成、区系特点、数量分布等研究。结果表明:(1)杭州湾海域春、秋两季共获得并鉴定出的鱼类有31种,隶属于9目15科,其中以石首鱼科和■虎鱼科的种类为最多,各有5种,分别占总种数的16.7%;鳀科鱼类次之,有4种,占总种数的13.3%,优势种有睛尾蝌蚪■虎鱼、龙头鱼、刀鲚、棘头梅童鱼;(2)根据鱼类适温性可将该海域的鱼类分为暖水性、暖温性和冷温性3种适温类型,以暖温性种类为主,暖水性种类次之,而冷温性种类极少,仅有1种;(3)根据其生态习性,可分为河口性、沿岸性和近海性3种生态类群;(4)渔获数量分布规律是春季在调查海域的内侧或者说中西部较高,而湾口较低,秋季则正好相反。  相似文献   
949.
杨仁超  董亮  张吉  王一  樊爱萍 《沉积学报》2022,40(1):267-280
苏里格气田西区气井产水严重,地层水成因、分布规律及控制因素不明确,成为制约该区致密砂岩气开发的关键科学问题.在大量测井数据、生产动态数据收集的基础上,分析了苏里格气田西部地层水性质及地球化学特征,结果发现:地层水矿化度高,整体属于盐水;水型主要为CaCl2型;pH值范围为6~6.9,呈弱酸性.分析认为:1)地层水主要为...  相似文献   
950.
2000~2004年天津市大气污染特征分析   总被引:2,自引:0,他引:2  
韩素芹  边海  解以扬 《气象科技》2007,35(6):787-791
根据天津市2000~2004年的环境监测资料和同期气象资料,对天津市大气污染物浓度变化的时空变化特征、大气污染与天气条件的关系进行了研究。结果表明:天津市大气污染物具有明显的时空分布规律,时间上表现为冬强夏弱,年际之间SO2和PM10浓度减轻,NO2变化不大。空间上表现为SO2和PM10在中心城区改善明显,NO2浓度在局部地区仍在增加。天气形势、城市热岛、逆温和混合层高度等对污染物浓度影响很大。  相似文献   
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