Spring phytoplankton production in the Western ross sea

Coastal zone color scanner (CZCS) imagery of the western Ross Sea revealed the Presence of an intense phytoplankton bloom covering >106,000 square kilometers in early December 1978. This bloom developed inside the Ross Sea polynya, within 2 weeks of initial polynya formation in late November. Primary productivity calculated from December imagery (3.9 grams of carbon per square meter per day) was up to four times the values measured during in situ studies in mid-January to February 1979. Inclusion of this early season production yields a spring-to-summer estimate of 141 to 171 grams of carbon per square meter, three to four times the values previously reported for the western Ross Sea.     

Side-scan sonar assessment of gray whale feeding in the bering sea

Side-scan sonar was used to map and measure feeding pits of the California gray whale over 22,000 square kilometers of the northeastern Bering Sea floor. The distribution of pits, feeding whales, ampeliscid amphipods (whale prey), and a fine-sand substrate bearing the amphipods were all closely correlated. The central Chirikov Basin and nearshore areas of Saint Lawrence Island supply at least 6.5 percent of the total gray whale food resource in summer. While feeding, the whales resuspend at least 1.2 x 10(8) cubic meters of sediment annually; this significantly affects the geology and biology of the region.     

Exposure of basement rock on the continental slope of the bering sea

Profiles of repetitive seismnic reflections reveal that the Bering con tinental slope, outer shelf, and rise overlay an acoustically reflective "basement" which extends at least 750 kilometers parallel to the trend of the slope. This acoustic basement is usually covered by several hundred meters of stratified sediments at the top and bottom of the slope; however, it is exposed in sub marine canyons and flanking spurs along the main part of the slope for a distance of at least 550 kilometers northwest of the Pribilof Islands. The lithologic composition and the age of the rocks of the acoustic basement are not known. However, its probable seismic velocity of 3.1 to 3.7 kilometers per second suggests that it is composed of volcanic rocks or lithified sedimentary rocks or both. The regional geology suggests that the acoustic basement is the upper surface of folded late Mesozoic rocks which were locally intruded by granite and serpentine. The structure of the Bering slope, as deduced from the acoustic profiles, suggests that the surface of the basement has been monoclinically flexed and faulted between the shelf edge and the deep Aleutian Basin.     

Ice-edge eddies in the fram strait marginal ice zone

Five prominent ice-edge eddies in Fram Strait on the scale of 30 to 40 kilometers were observed over deep water within 77 degrees N to 79 degrees N and 5 degrees W to 3 degrees E. The use of remote sensing, a satellite-tracked buoy, and in situ oceanographic measurements showed the presence of eddies with orbital speeds of 30 to 40 centimeters per second and lifetimes of at least 20 days. Ice ablation measurements made within one of these ice-ocean eddies indicated that melting, which proceeded at rates of 20 to 40 centimeters per day, is an important process in determining the ice-edge position. These studies give new insight on the formation, propagation, and dissipation of ice-edge eddies.     

Diel periodicity of photosynthesis in polar phytoplankton: influence on primary production

In the Southern Ocean, primary production estimated from seasonal chemical and geochemical changes is two to four times greater than the value calculated from carbon-14 uptake. Since carbon uptake had typically been measured only during midday incubations, the influence of diel periodicity of photosynthesis on daily productions was not considered. Phytoplankton from McMurdo Sound, Antarctica, exhibited distinct, but seasonally variable diel patterns of light-saturated and light-limited photosynthesis. Maximum photosynthetic capacity occurred about noon in early September, and its occurrence progressively shifted to about midnight by late October. This shift was accompanied by a concomitant phase shift in the occurrence of minimum photosynthetic capacity from midnight to midday. Daily production estimated from time-of-day corrected photosynthetic characteristics and from 24-hour incubations was 2.5 to 4 times greater than that predicted from 6-hour midday incubations. If similar diel periodicity in photosynthesis occurs in other polar oceans, primary production would be significantly higher than previously estimated from carbon-14 uptake measurements.     

Remote sensing of the fram strait marginal ice zone

Sequential remote sensing images of the Fram Strait marginal ice zone played a key role in elucidating the complex interactions of the atmosphere, ocean, and sea ice. Analysis of a subset of these images covering a 1-week period provided quantitative data on the mesoscale ice morphology, including ice edge positions, ice concentrations, floe size distribution, and ice kinematics. The analysis showed that, under light to moderate wind conditions, the morphology of the marginal ice zone reflects the underlying ocean circulation. High-resolution radar observations showed the location and size of ocean eddies near the ice edge. Ice kinematics from sequential radar images revealed an ocean eddy beneath the interior pack ice that was verified by in situ oceanographic measurements.     

Mesoscale oceanographic processes beneath the ice of fram strait

A major component of the Fram Strait Marginal Ice Zone Experiment was the investigation of air-sea-ice interactions, processes, and circulation patterns found behind the local ice edge and on scales greater than 10 kilometers (mesoscale and large scale). Neutrally buoyant floats, ice-tethered cyclesondes, and helicopter-based measurements were used to obtain uniquely integrated and consistent views of the mesoscale ocean features beneath the ice cover of Fram Strait. Within the vicinity of the Yermak Plateau, three distinct regions of mesoscale motion were observed that coincided with the shallow topography of the plateau, the northward flowing Atlantic water over the western flank of the plateau, and the strong current-shear zone of the East Greenland Polar Front. A subice meander of the front was also observed, which was probably occluded subsequently.     

Supershrimp: deep bioturbation in the strait of canso, nova scotia

Axius serratus, a crustacean thought to be extremely rare, was discovered in large numbers in polluted regions of the Strait of Canso. The shrimp may live deeper than 3 meters in the sediment; burrows are kept open to at least 2.5 meters. Sediment contained in old filled burrows is anomalous in its distribution of particle size and its content of water, organic carbon, and trace elements. These anomalous qualitites affect the geotechnical properties of sediments on the sea floor.     

区域经济整合与台湾海峡经济区构建

文章根据当前形势,从两岸经贸合作的必然趋势与客观条件着手,提出了建立台湾海峡经济区的构想。     

Ocean dynamics and acoustic fluctuations in the fram strait marginal ice zone

Acoustic waves transmitted over a 100-kilometer path in the Fram Strait marginal ice zone undergo Doppler shifts and fluctuations around these shifts, the former due to quasi-steady motion of both acoustic source and receiver and the latter to unsteady motions of the water column and ice cover. Internal waves and differential Doppler shift usually account for such fluctuations in the deep temperate ocean but only partially explain the results obtained in the marginal ice zone. There the fluctuations are more energetic and may be caused alternatively or additionally by comparably energetic fluctuations in ice-edge eddies or other mesoscale motions.     

西部大开发环境下西部图书馆的职能刍议

本文探讨了西部图书馆如何充分发挥其职能 ,为西部开发提供优质服务的有关措施     

不同粒级浮游植物对淡水初级生产力的作用

用黑白瓶测氧法，研究了大连市3个水体（植物园、儿童公园、马栏河）不同粒级浮游植物（＜200μm、＜20μm、＜2μm）对水体生物量和初级生产力的作用。结果表明：3水体的营养状况植物园是中营养型，绿藻占优势；儿童公园和马栏河是富营养型，分别以绿藻和硅灌占优势。随着水体富营养化增强，超微藻类对浮游植物生物量和初级生产力的作用减小。3个水体中＜20μm的微型藻类和超微藻类对水体的初级生产力和生物量贡献最大，其初级生产力分别占各自总初级生产力的53．7％、57．2％、63．2％。文中与其他作者关于海洋、淡水超微藻类的研究结果进行了比较。     

淡水鱼池浮游植物和浮游细菌数量动态及超微藻类对初级生产力的贡献

于2002年4月²003年3月对辽宁省碧流河水库渔业总公司鲢、鳙亲鱼池塘中浮游植物种类组成和生物量变化以及浮游细菌、超微藻类的数量动态进行了研究,并采用黑白瓶法将超微藻类产氧量与浮游植物初级生产力进行了比较。结果表明:浮游植物共计64属88种,以绿藻、蓝藻居多,生物量变动于0.362003年3月对辽宁省碧流河水库渔业总公司鲢、鳙亲鱼池塘中浮游植物种类组成和生物量变化以及浮游细菌、超微藻类的数量动态进行了研究,并采用黑白瓶法将超微藻类产氧量与浮游植物初级生产力进行了比较。结果表明:浮游植物共计64属88种,以绿藻、蓝藻居多,生物量变动于0.36²66.21 mg/L,平均为(86.39±26.12)mg/L;浮游细菌和超微藻类的数量分别为(1.01266.21 mg/L,平均为(86.39±26.12)mg/L;浮游细菌和超微藻类的数量分别为(1.01⁸.50)×1010个/mL和(0.348.50)×1010个/mL和(0.34⁵.71)×103个/mL;细菌数量高峰期出现在夏季8、9月,秋季以后有所下降,而超微藻类的数量则随季节变化不明显;超微藻类产氧量(毛产量)占浮游植物初级生产力的23%5.71)×103个/mL;细菌数量高峰期出现在夏季8、9月,秋季以后有所下降,而超微藻类的数量则随季节变化不明显;超微藻类产氧量(毛产量)占浮游植物初级生产力的23%⁹3%;浮游细菌和超微藻类的数量分别与水温和氨氮等生态因子显著相关。     

淡水鱼池浮游植物和浮游细菌数量动态及超微藻类对初级生产力的贡献

于2002年4月~2003年3月对辽宁省碧流河水库渔业总公司鲢、鳙亲鱼池塘中浮游植物种类组成和生物量变化以及浮游细菌、超微藻类的数量动态进行了研究,并采用黑白瓶法将超微藻类产氧量与浮游植物初级生产力进行了比较。结果表明:浮游植物共计64属88种,以绿藻、蓝藻居多,生物量变动于0.36~266.21 mg/L,平均为(86.39±26.12)mg/L;浮游细菌和超微藻类的数量分别为(1.01~8.50)×1010个/mL和(0.34~5.71)×103个/mL;细菌数量高峰期出现在夏季8、9月,秋季以后有所下降,而超微藻类的数量则随季节变化不明显;超微藻类产氧量(毛产量)占浮游植物初级生产力的23%~93%;浮游细菌和超微藻类的数量分别与水温和氨氮等生态因子显著相关。     

水稻规模农户生产环节对机械化服务外包的选择

以浙江省3个县的148个样本农户调查数据为基础,通过构建多元线性回归模型对影响农户生产环节选择外包机械化服务的因素进行实证分析。结果表明:随水稻Oryza sativa栽培面积增加,生产环节中农户接受社会化服务概率先增大后减少,呈"倒U"型,存在明显的规模经济效应;户主年龄对接受机械化服务程度有显著的正向影响;农机手的经历、家庭拥有农机数量以及土地破碎化等因素对接受机械化服务有显著负向影响。在此基础上提出培育多种服务主体、鼓励土地整理、为机械化外包服务提供良好发展环境等政策建议。     

Distributions of phytoplankton blooms in the southern ocean

A regional pigment retrieval algorithm for the Nimbus-7 Coastal Zone Color Scanner (CZCS) has been tested for the Southern Ocean. The pigment concentrations estimated with this algorithm agree to within 5 percent with in situ values and are more than twice as high as those previously reported. The CZCS data also revealed an asymmetric distribution of enhanced pigments in the waters surrounding Antarctica; in contrast, most surface geophysical properties are symmetrically distributed. The asymmetry is coherent with circumpolar current patterns and the availability of silicic acid in surface waters. Intense blooms (>1 milligram of pigment per cubic meter) that occur downcurrent from continental masses result from dissolved trace elements such as iron derived from shelf sediments and glacial melt.     

海峡两岸加入WTO前瞻农业保鲜真空预冷技术

海峡两岸加入 WTO后 ,农产品保鲜冷藏技术的研究成为一项重要的课题。本实验在台北科技大学的真空及冷冻技术研究基础上 ,进行了全自动化的真空预冷机的开发研究。研究结果表明 :该套设备减少了农产品在制冷过程中碰伤率 ,叶菜类 7分钟之内温度降至 4℃左右 ,其中甘蓝在 2 0分钟内达到 6℃以下的均温。     

秃尾河年径流变异点综合诊断研究

研究流域水文水资源的演变规律,可为流域水资源开发利用和保护以及区域社会经济的可持续发展提供重要的决策依据。本研究以秃尾河流域出口水文站高家川站1956—2004年年平均流量和年降水量资料为主,对该流域径流和降水的趋势性和跳跃性进行了分析诊断,结果表明该流域降水的趋势性和跳跃性不显著;而径流具有非常显著的减小趋势,经多种方法综合诊断,最终确定了该流域径流在1978年发生跳跃变异,最后结合实际水文调查资料从成因上 对结果进行了合理性论证。综合诊断有效地解决了单一检验方法检验结果可信度较差,多种检验方法检验结果不一致的问题,对复杂的时间序列变异点的识别与检验有一定的效果。     

两岸农业合作对台湾农产品贸易的影响

本文根据海峡两岸农业合作程度不同,将海峡两岸农业合作置于不同的阶段加以考虑,提出海峡两岸农业合作对台湾农产品贸易带来的影响,同时认为两岸农业合作的顺利进行有利于台湾农产品贸易的发展。