The hydrographic features of the ocean region around the Ryukyu Islands during summer of 1997

IwnODUCTIONTheECSandthePacificOceanareseparaedbytheRyUkyUIs1andshavingthreermnPasSagesforwaerexchangbebeenthesetWowateboies.TheKewshioenterstheECS~ghthestraiteastofTaiwanIslandandflowsbacktothePacificOceantboghTugalaStrait.TheOkinawIsland-MiyakoIslandstralt(KeanTrench,withdepth>1opm)allowalopqUanityofwaerexchangebetweentheECSandthePacifico-cean(YUanandPan,l994).InvestigationdatashowsthatthehydIDgraPhicfeatUresoftheoceanregionarOUntheRyukyUIslandsareverycomPlicated.Somcold…     

THERMOHALINE FINESTRUCTURE AND ITS RELATION WITH THE WATER MASSES AND CURRENTS SYSTEM IN THE NORTHERN EAST CHINA SEA

Eighy-one CTD profiles gathered in springtime were used for northem East China Sea tbermohalinefinestructure studies indicating that the finestructure properties vaned with region and depth, as shown infinesructure specra, distribution of Cox numbers etc..Some results closely wiated to distribution of watermasses and Analysis of two typical profiles revealed differenes in autospectra of temperature,salihity and potential density gradients, probobility distribution of temperature finestructure gradient,Cox numberc.etc. The probability density function of vertical temperature gradients, which varied withsample interval, is given. The variances of temperatare finestructare gradient are used to estimate the lat-eral diffusivity and lateral temperatare flux, which were 10.3 (m~2/s) and 5.5×10~(-4) (℃ m/s),respectivly.     

THE STRENGTH OF THE DISSOLVED OXYGEN MAXIMUM IN THE VERTICAL DISTRIBUTION OF NANSHA ISLANDS WATERS

Observation data from a cruise in the Nansha Islands, in May to June 1990, December, 1993, September to October 1994, and July, 1999, respectively, were used to develop the method presented here to indicate the existing strength of the dissolved oxygen maximum in the vertical distribution of Nansha Islands waters. Its seasonal variation and regional distribution are discussed in this paper. Analysis results showed that the distribution of the strength of dissolved oxygen maximum (DOmax-DOsur) was closely related to the upper layer circulation and the bioactivity of Nansha Islands seawater.     

Type and evolution of landscapes of Nansha Islands

Landscapes of the Nansha Islands may be divided into five types: tropical marine organism-breeding landscape of reef knoll like Zengmu Shoal, Wan’an Bank and so on; tropical marine organism-breeding landscape of atoll including all emerged reefs and most submerged reefs; tropical evergreen arbor-bush forest and phosphorous lime soil landscape of limesand Islets like Taiping Islet, Nanwei islet and so on; tropical shallow sea marine organism-breeding landscape of southern continental shelf; tropical oceanic and deep-sea marine organism landscape in middle and north parts of the Nansha Islands area. These five landscape types may be also summed up as two categories, one is tropical sea landscape including those in shallow and deep sea, the other is tropical coral reef landscape including those of reef knoll, atoll and limesand islet. This paper outlines the evolutional model of landscapes of the Nansha Islands. The distribution and evolution of landscape types are related with palaeogeography and modern environmental conditions. The former shallow sea of the Nansha islands was coastal zone in the Late Pleistocene epoch. Deep sea is evolved from shallow sea due to long and slow subsidence of crust. Modern coral reefs develop on old reef top of the Late pleistocene epoch or on baserock of continental shelf in the Holocene due to the rise of sea level in postglacial. Limesand islet is in the peak of developmental stage.     

A STUDY ON THE FLORISTIC PLANT GEOGRAPHY OF XISHA ISLANDS, SOUTH CHINA

邢福武，李泽贤，叶华谷，陈炳辉，吴德邻ＡＳＴＵＤＹＯＮＴＨＥＦＬＯＲＩＳＴＩＣＰＬＡＮＴＧＥＯＧＲＡＰＨＹＯＦＸＩＳＨＡＩＳＬＡＮＤＳ，ＳＯＵＴＨＣＨＩＮＡ￥ＸｉｎｇＦｕｗｕ；ＬｉＺｅｘｉａｎ；ＹｅＨｕａｇｕ；ＣｈｅｎＢｉｎｇｈｕｉ；ＷｕＤｅｌｉｎ（...     

Type and evolution of landscapes of Nansha Islands

ＴＹＰＥＡＮＤＥＶＯＬＵＴＩＯＮＯＦＬＡＮＤＳＣＡＰＥＳＯＦＮＡＮＳＨＡＩＳＬＡＮＤＳＺｈａｏＨｕａｎｔｉｎｇ（赵焕庭）ＳｏｕｔｈＣｈｉｎａＳｅａＩｎｓｔｉｔｕｔｅｏｆＯｃｅａｎｏｌｏｇｙ,ｔｈｅＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＳｃｉｅｎｃｅｓ,Ｇｕ...     

THE NOMENCLATURE OF THE SOUTH CHINA SEA ISLANDS IN ANCIENT CHINA

ＴＨＥＮＯＭＥＮＣＬＡＴＵＲＥＯＦＴＨＥＳＯＵＴＨＣＨＩＮＡＳＥＡＩＳＬＡＮＤＳＩＮＡＮＣＩＥＮＴＣＨＩＮＡ￥ＬｉｕＮａｎｗｅｉ（刘南威）（ＤｅｐａｒｔｍｅｎｔｏｆＧｅｏｇｒａｐｈｙ，ＳｏｕｔｈＣｈｉｎａＮｏｒｍａｌＵｎｉｖｅｒｓｉｔｙ，Ｇｕａｎｇｚ...     

南沙群岛西南陆架区深水金线鱼的资源现状

根据 2003年南沙群岛西南陆架区春秋两次调查资料,分析南沙群岛西南陆架区深水金线鱼的资源现状。结果表明,深水金线鱼分布广泛,平均渔获率为 9. 9kg·h-1,渔获率有明显的季节变动,秋季高于春季,密集分布于 71~80m水深。其群体组成也有季节差异,春季的平均体长、平均体重大于秋季,优势体长组春季为 131 ~140mm,秋季为 121~130mm,渔获优势年龄组为Ⅰ ~Ⅱ龄鱼。目前其资源密度及资源量分别为 129. 41kg·km-2和9 .484 21t,资源量是原始资源量的 46%,该资源已明显衰退。同时文中还讨论了合理利用该资源的措施。     

APPROACH TO THE REGIONALIZATION OF AGRICULTURAL—PASTURALIZATION AROUND CHANGSHAN ISLANDS IN NORTHERN YELLOW SEA

Based on the data of resources,environment and foundation of production,applying principal compo-nents-clustering quantitative analysis,this article divides the maritime space of Changshan Islands into three regions of agricultural-pasturalization,providing a scientific basis for the rational distribution of marine cultivation.The three re-gions are as follows:1)The region of an agricultural-pasturalization in the northern part of maritime space.It includes Da Wangjia and Shicheng islans.The main production is cultivation of prawn and mollusks in sea beach,float raft culture of mussel in shallow sea and scallop ,and breeding of sea cucumber in submarine.2)The region of agricultur-al-pasturalization in the middle western part of maritime space.It includes Da Changshan and Guanglu islands and west-ern part of Xiao Chengshan Island.The man production is folat raft culture of mussel and scallop in shallow sea,and breed-ing of sea cucumber in submarine.3)The region of agricultural-pasturlization of the southeastem part of maritime space.It includes the eastern part of Xiao Chan Island,Haiyang and Zhangzi islands.The main production is breeding of abalone,sea cucumber,algaes and fish.     

Nature, source and composition of volcanic ash in surficial sediments around the Zhongsha Islands

Volcanic detrital sediments are a unique indicator for reconstructing the petrogenetie evolution of submarine volcanic terrains. Volcanic ash in surficial sediments around the Zhongsha Islands includes three kinds of volcanogenic detritus, i.e., brown volcanic glass, colorless volcanic glass and volcanic scoria. The major element characteristics show that bimodal volcanic activity may have taken place in the northern margin of the South China Sea, with brown volcanic glass and colorless volcanic glass repre-senting the maric end-member and felsie end-member, respectively. Fractional crystallization is the main process for magma evolu-tion. The nature of the volcanic activity implies that the origin of volcanic activity was related to extensional tectonic settings, which is corresponding to an extensional geodynamie setting in the Xisha Trench, and supports the notion, which is based on geophysical data and petrology, that there may exist a mantle plume around the Hainan Island.     

Dinophysis caudata generated lipophilic shellfish toxins in bivalves from the Nanji Islands,East China Sea

A 12-month program of monitoring potentially toxic microalgae(that produce lipophilic shellfi sh toxins; LSTs) and their toxins in bivalves was conducted from April 2006 to March 2007 in the Nanji Islands, East China Sea. Two Dinophysis species, D. caudata and D. acuminata, were identifi ed, and D. caudat a was found to be the dominant species. D. caudata was detected in water samples between April and June 2006, and between February and March 2007. It reached its highest abundances in May, with a mean abundance of 1.38×10 2 cells/L in surface water and 1.25×10 2 cells/L in bottom water(10 m deep). The temporal distribution of D. caudata was associated with the occurrence of LSTs in bivalve samples, which mostly occurred at the same time as D. caudata blooms, between April and July 2006. All of the cultured bivalves sampled between April and June were contaminated with LSTs, with an average toxicity of 85 μg okadaic acid(OA) eq./100 g meat, which was four times higher than the Chinese regulatory limit(20 μg OA eq./100 g meat). Ten out of fi fteen wild samples(66.7%) collected during the same period were positive for LSTs, and contained an average LST toxicity of 45 μg OA eq./100 g meat(more than twice the regulatory value). Cultured Patinopecten yessoensis collected on 15 May 2006 had the highest toxicity, 320 μg OA eq./100 g meat, and relatively high toxicities(80 to 160 μg OA eq./100 g meat) were found in bivalves until the end of July.     

Effect of water depth on wind-wave frequency spectrum II. Verification and comparison

The spectrum derived in Part I of the present paper is here systematically verified with field data and compared at some length with that obtained by multiplying the deep-water spectrum with the Kitaigorodskii factor. Project supported by the National Natural Science Foundation of China.     

Mean properties of mesoscale eddies in the Kuroshio recirculation region

Using a 19-year altimetric dataset, the mean properties and spatiotemporal variations of eddies in the Kuroshio recirculation region are examined. A total of 2 001 cyclonic tracks and 1 847 anticyclonic tracks were identifi ed using a geometry-based eddy detection method. The mean radius was 57 km for cyclonic eddies and was 61 km for anticyclonic eddies, respectively, and the mean lifetime was about 10 weeks for both type eddies. There were asymmetric spatial distributions for eddy generation and eddy termination, which were domain-dependent. Mean eddy generation rates were 2.0 per week for cyclonic eddies and were 1.9 per week for anticyclonic eddies. Both type eddies tended to deform during their lifetime and had different propagation characteristics, which mainly propagated westward and southwestward with velocities 4.0–9.9 cm/s, in the Kuroshio recirculation region. Further discussion illustrates that the eddy westward speed maybe infl uenced by the combined effect of vertical shear of horizontal currents and nonlinearity of eddy. To better understand the evolution of eddy tracks, a total of 134 long-lived tracks(lifetime ≥20 weeks) were examined. Comparison between short-span eddies(lifetime ≥4 weeks and 20 weeks) and long-lived eddies is also conducted and the result shows that the short-span and long-lived eddies have similar time evolution. Finally, eddy seasonal variations and interannual changes are discussed. Correlation analysis shows that eddy activity is sensitive to the wind stress curl and meridional gradient of sea surface temperature on interannual timescales. Besides, the strength and orientation of background fl ows also have impacts on the eddy genesis.     

Trends in temperature and precipitation extremes over Circum-Bohai-Sea region, China

Trends in temperature and precipitation extremes from 1961 to 2008 have been investigated over Circum-Bohai-Sea region,China using daily temperature and precipitation data of 63 meteorological stations.The re-sults show that at most stations,there is a significant increase in the annual frequency of warm days and warm nights,as well as a significant decrease in the annual frequency of cold days,cold nights,frost days,and annual diurnal temperature range(DTR).Their regional averaged changes are 2.06 d/10yr,3.95 d/10yr,-1.88 d/10yr,-4.27 d/10yr,-4.21 d/10yr and-0.20℃/10yr,respectively.Seasonal changes display similar patterns to the annual results,but there is a large seasonal difference.A significant warming trend is detected at both annual and seasonal scales,which is more contributed by changes of indices defined by daily minimum temperature than those defined by daily maximum tem-perature.For precipitation indices,the regional annual extreme precipitation displays a weak decrease in terms of magnitude and frequency,i.e.extreme precipitation days(RD95p),intensity(RINTEN),proportion(RPROP) and maximum consecutive wet days(CWD),but a slight increase in the maximum consecutive dry days(CDD),which are consistent with changes of annual total precipitation(PRCPTOT).Seasonally,PRCPTOT and RD95p both exhibit an increase in spring and a decrease in other seasons with the largest decrease in summer,but generally not significant.In summary,this study shows a pronounced warming tendency at the less rainy period over Circum-Bohai-Sea region,which may affect regional economic development and ecological protection to some extent.     

多尺度卫星重力场分解与场源深度关系研究

以直立六面体模型为基础,使用相关分析研究小波基和小波阶数的选取,同时对功率谱深度估计方法进行实验。结果表明,使用恰当的小波基和小波阶数分解重力场,可以获取地层深部信息。计算的南海北部陆缘地区及其范围内珠江口、台西南盆地的莫霍面深度分别为28.3、23.9、20.8 km,与文献资料基本一致。     

闽粤地区同震形变波记录序列分析及小波能谱特征

基于闽粤地区10个地形变观测点40个测项的同震形变波记录,利用幅度比值和小波多尺度分析方法探讨其记录特点和传导机制,结果显示：1)同震形变波到时与震中距有关,波形记录含有d-P和d-S波,不同测项记录到的波形不一致,同测项的记录波形相似;2)幅度比值在一定程度上与震源方位有关,进一步反映其各向异性;3)通过互（自）相关计算和滤波处理,能识别出同震形变波的频带为002~0.04 Hz,峰值在0025 Hz附近;4)智利地震形变波序列小波能谱为64~254 s,能量集中在128~254 s;而尼泊尔地震形变波在不同测点区别较大,潮州台为16~32 s,厦门台为16~64 s。研究结果表明,形变记录中除面波外还包含体波成分,不同震源机制引起的同震形变波传导机制可能存在各向异性,这对于开展地震引发应变等研究有借鉴意义。     

达州市气候变化的特征分析

基于达县测站1961-2007年的地面常规观测资料,主要采用小波分析,结合趋势分析、功率谱分析等方法分析了达州市47年来近地表气温、降水随时间的变化特征.结果表明,达州市近50年来冬季(年平均)地表气温变暖幅度约为0.9℃(0.4℃),增温速率接近0.18℃/10a(0.08℃/10a),低于全球的升温幅度.利用小波分析方法研究冬季气温的周期性发现,达州市的冬季气温存在着明显的8年和50年以上的特征时间尺度和周期性振荡.通过对降水的趋势分析发现,夏季降水的增加幅度比年均显著.小波分析方法结果显示达州市的夏季降水同样存在50年以上的特征时间尺度,但在小尺度上20世纪70年代末前后存在不同的变化特征.     

Effect of Ploughing Depth on the Growth and Yield of Heracleum candicans： a Threatened Medicinal Herb and a Less-explored Potential Crop of the Himalayan Region

This paper examines the effect of ploughing depths （A -- 60 cm, B -- 45 cm and C -- 30 cm） on the growth and yield of Heracleum candicans Wall （Apiaceae）, a threatened medicinal herb of the Himalayan region. This less-explored plant is being suggested as a potential crop for the mountain agriculture. The study was carried out in an orchard in Himachal Pradesh, India at 2500 m altitude, for two successive growth years. During the first year, all plants remained in juvenile state; in the second year, nearly 65 % plants produced flowers only under 60cm ploughing depth. Among its morphological traits, plant height, collar diameter and aboveground flesh weight were found to be strongly correlated （P 〈 0.01） with the belowground biomass during the first year （r =0.968, 0.925 and 0.973, respectively） and during the second year （r=0.945, 0.928 and 0.775, respectively）. Increase in the ploughing depth was significantly correlated （P〈0.01） with all growth parameters, including the belowground dry weight, marketable portion of the produce. The belowground biomass （commercial yield; 16.28 Qt/hec） at depth A was about 2.6 and 4.7 times higher than those recorded at depths B and C, respectively. The results clearly justify the importance of deep ploughing and this paper strongly recommends it for economically sustainable cropping.     

我国海岛开发存在的问题及对策研究

我国海岛资源开发利用在环境、管理和经济等方面存在诸多问题。环境问题主要包括：海岛及其周围海域生物多样性的丧失,海岛淡水资源紧张,周围海域环境污染,陆海通道和围海工程造成海域自然环境状况改变；管理问题主要包括：海岛管理体制不健全,海岛资源权属不清,海岛开发管理法规不完善；经济问题主要包括：海岛地区经济基础薄弱,海岛开发产业布局不合理。最后提出我国海岛资源开发利用应该：建立有效的海岛综合管理体系和机构；因地制宜开发利用海岛资源；增加海岛资金投入,逐步扩大海岛对外开放力度；大力发展海岛科教事业, 实施人才战略。     

Geochemical characteristics of temperature and pressure of Paleozoic reservoir fluid inclusions in Xuanjing region,Lower Yangtze area

In order to understand the geochemical characteristics of Paleozoic reservoir fluids in Xuanjing region, Lower Yangtze area, drilling core samples from Y and D wells were tested and analyzed to study the fluid inclusion types and composition. Pressure correction was undertaken to determine the temperature and pressure environment for inclusion formation, and the influence of fluid characteristics of the Upper Permian and Lower Triassic reservoirs on the preservation of shale gas was investigated...