Variation of d δ18O/dT in precipitation in the Qinghai-Xizang Plateau

The relations between δ¹⁸O and temperature on the different time scales were analysed, according to the data from Tuotuohe (34°13′N, 96°25′E; 4533 m a. s. l.), Delingha (37°22′N, 97°22′E; 2981 m a. s. l.) and Xining (36°37′N, 101°46′E; 2261 m a. s. l.) in the Qinghai-Xizang Plateau. The results show that the significance of d δ¹⁸O/dT on different time scales are different. The d δ¹⁸O/dT on the synoptic scale reflects the interdependent relation between δ¹⁸O and temperature in the short-term synoptic scale process; the d δ¹⁸O/d T on the seasonal scale reflects the relation between them whithin a year; and the d δ¹⁸O/d T on the climatic scale reflects the relation between them in the long-term climatic change. The calculated d δ¹⁸O/dT on climatic scale is very close to the theoretical values on the condition of advection transport for Tuotuohe Station. However, there are great differences between the calculated and the theoretical values for Delingha and Xining stations.     

Seasonal variation in fatty acid composition of seston and the copepod Calanus sinicus (Brodsky, 1962) in Jiaozhou Bay and its trophic implications

The fatty acid compositions of seston and Calanus sinicus were investigated to study trophic relationships in Jiaozhou Bay. Principal component analysis was carried out to ordinate the fatty acid patterns of seston in stations and months. The results showed that diatoms were most abundant in the phytoplankton at station A5 (located in the northwest of the bay:36°9′N, 120°20′E) and least abundant at station D7 (located outside of the bay: 35°59′N, 120°26′E). By contrast, dinoflagellates were most abundant at station D7 and least abundant at station A5. According to the annual variations of 16:1ω7 and 18:4ω3/ 16:1ω7, diatoms flourished mainly in spring and summer, while dinoflagellates bloomed exclusively in summer. A distinctive feature of the fatty acid composition of C. sinicus was the prevalence of 20:5ω3 and 22:6ω3. The higher content of 16:1ω7 over 18:4ω3 in females indicated that diatoms contributed more than dinoflagellates to the diet of C. sinicus. The feeding intensity of C. sinicus on diatoms was higher in spring and autumn than in other seasons. The herbivorous indicators 20:1 and 22:1 were comparatively low, suggesting that besides phytoplankton, C. sinicus might feed on a wider range of particles including organic detritus, bacteria and small copepods.     

Two new species of Ophidiasterid sea-stars from the vicinity of Diaoyudao,East China Sea

Two new species of the asteroid family Ophidiasteridae are described from two specimens collected by commercial fishery vessels of Qingdao from the vicinity of Diaoyudao (25°45′N, 123°15′E), East China Sea.Hacelia tuberculata sp. nov. shows affinities withH. tyloplax (H. L. Clark, 1914) andLinckia gracilis sp. nov. is related toL. laevigata (Linnaeus). Contribution No. 1163 from the Institute of Oceanology, Academia Sinica.     

Optimal salinity for dominant copepods in the East China Sea, determined using a yield density model

From 1997 to 2000, four field surveys were conducted in the East China Sea (ECS) (23°30′–33°00′N, 118°30′–128°00′E). A field data yield density model was used to determine the optimal salinities for 19 dominant copepod species to establish the relationship between surface salinities and abundance of those species. In addition, ecological groups of the copepods were classified based on optimal salinity and geographical distribution. The results indicate that the yield density model is suitable for determining the relationship between salinity and abundance. Cosmocalanus darwini, Euchaeta rimana, Pleuromamma gracilis, Rhincalanus cornutus, Scolecithrix danae and Pareucalanus attenuatus were determined as oceanic species, with optimal salinities of >34.0. They were stenohaline and mainly distributed in waters influenced by the Kuroshio or Taiwan warm current. Temora discaudata, T. stylifera and Canthocalanus pauper were nearshore species with optimal salinities of <33.0 and most abundant in coastal waters. The remaining 10 species, including Undinula vulgaris and Subeucalanus subcrassus, were offshore species, with optimal salinity ranging from 33.0–34.0. They were widely distributed in nearshore, offshore and oceanic waters but mainly in the mixed water of the ECS.     

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（...     

Study on the dominant species of Pteropoda in East China Sea

1 INTRODUCTION Pteropoda is a group of marine pelagic mol- lusks, which belongs to Opisthobranchia of Gastro- poda. Although Pteropoda is not a major group in pelagic zooplankton in terms of abundance and number of species, their ecological characters are…     

Temporal and spatial distributions of dominant shrimp stocks and their relationship with the hydrological environment in the East China Sea

To provide a scientific and technological base for fishery administration, holding a moratorium on fishing, and combating habitat degradation, a shrimp stock survey was carried out in May, August, and November 1998 and in February 1999. The study was conducted in the area between 26o00′ N and 33o00′ N and to the west of 127o00′ E in the East China Sea using a multi-sac trawl-net, with 115 stations being sampled. Up to 2001, we had found 121 species, which belong to 63 genera under 22 families, and 41 species are of high economic value and in great abundance. Nine shrimp species were of great economic importance, whose stock accounted for 76.8% of the demersal total. They were Parapenaeus fissuroides, Metapenaeopsis philippi, Palaemon gravieri, Metapenaeopsis barbata, Solenocera koelbeli, Solenocera crassicornis, Trachypenaeus curvirostris, Solenocera melantho and Parapenaeopsis hardwickii (listed in stock order). The nine species belong to the eurythermal and eurysaline community and high thermal and high saline community, had different migration patterns and stocks, and their distribution patterns could be generally classified into three types:(1) dominating in the north or the south;(2) dominating to the north of and in the coast to the south of 30o00′ N;and (3) dominating to the east of 60 m isobath, which were related to six water masses in the ECS near two lines, i.e., the 60 m isobath and 30o00′N latitudinal lines. Densely habited shrimps were found in all four seasons due to temperature and salinity frontiers and upwelling. The general stock density index was relatively higher in spring, summer, and autumn, when it surpassed 10 kg/h, while in winter, it was only 6.8 kg/h which might be caused by overfishing. According to the spawning areas of the nine species and their distribution patterns, to attain sustainable development of the shrimp fishery in the ECS, it is imperative to protect fishing areas and to hold a moratorium on catching to the west of 60 m isobath from April through October, and between 60 m and 100 m isobaths and to the south of 30oN from June through August and to limit fishing in winter.     

A singular spectrum analysis on Holocene climatic oscillation from lake sedimentary record in Minqin Basin, China

The total organic carbon (TOC) content series from the lake sediment of Minqin Basin (100°57′–104°57′E, 37°48′–39°17′N) in northwestern China, which has a 10 000-year-long paleo-climatic proxy record, was used to analyze the Holocene climate changes in the local region. The proxy record was established in the Sanjiaocheng (SJC), Triangle Town in Chinese, Section (103°20′25″E, 39°00′38″N), which is located at the northwestern boundary of the present Asian summer monsoon in China, and is sensitive to global environmental and climate changes. Applying singular spectrum analysis (SSA) to the TOC series, principal climatic oscillations and periodical changes were studied. The results reveal 3 major patterns of climate change regulated by reconstructed components (RCs). The first pattern is natural long-term trend of climatic change in the local area (Minqin Basin), indicating a relatively wetter stage in early Holocene (starting at 9.5 kaBP), and a relatively dryer stage with a strong lake desiccation and a declined vegetation cover in mid-Holocene (during 7–6 kaBP). From 4.0 kaBP to the present, there has been a gradually decreasing trend in the third reconstructed component (RC3) showing that the local climate changed again into a dryer stage. The second pattern shows millennial-centennial scale oscillations containing cycles of 1 600 and 800 years that have been present throughout almost the entire Holocene period of the last 10 000 years. The third pattern is a millennial-centennial scale variation with a relatively smaller amplitude and unclear cycles showing a nonlinear interaction within the earth’s climate systems.     

Phytoplankton Assemblage of Yangtze River Estuary and the Adjacent East China Sea in Summer, 2004

A cruise was conducted from late August to early September 2004 with the intention of obtaining an interdisciplinary understanding of the Yangtze River Estuary including the biological, chemical and physical subjects. Water sample analysis indicated that total phytoplankton species richness was 137. Of them 81 were found in Bacillariophyta and 48 in Pyrrophyta, accounting for 59.1% and 35.0% respectively. The average cell abundance of surface water samples was 8.8×104 cells L-1, with the maximum, 102.9×104 cells L-1, encountered in the area (31.75°N, 122.33°E) and the minimum, 0.2×104 cells L-1, in (30.75°N, 122.17°E). The dominant species at most stations were Skeletonema costatum and Proboscia alata f. gracillima with the dominance of 0.35 and 0.27. Vertical distribution analysis indicated that obvious stratification of cell abundance and dominant species was found in the representative stations of 5, 18 and 33. Shannon-Wiener index and evenness of phytoplankton assemblage presented negative correlation with the cell abundance, with the optimum appearing in (30.75°N, 122.67°E). According to the PCA analysis of the environmental variables, elevated nutrients of nitrate, silicate and phosphate through river discharge were mainly responsible for the phytoplankton bloom in this area.     

Numerical Simulation of Wintertime Mesoscale Eddies in the East China Sea

INTRODUCTIONAnimportantachievementofoceanographysincethe 1960swasthediscoveryofmesoscaleed dieswithspatialscaleofhundredsofmeters,andtimescaleofhours;andaverageflowvelocityofabout 10cm s.Theenormousenergyofthemesoscaleeddyiscomparabletothatofacycloneoran ticycloneintheatmosphere .Themesoscaleeddyisoneoftheimportantfactorsthatdecidethechangeoftheocean .Intherecentdecades,ChineseandforeignscientistshavedonelotsofworkontheEastChinaSeasmesoscaleeddies,theformationmechanismofwhicharethefocuso…     

RELATIONSHIP BETWEEN QINGHAI LAKE LEVEL DESCENDING AND ARTIFICIAL WATER－CONSUMPTION

ＲＥＬＡＴＩＯＮＳＨＩＰＢＥＴＷＥＥＮＱＩＮＧＨＡＩＬＡＫＥＬＥＶＥＬＤＥＳＣＥＮＤＩＮＧＡＮＤＡＲＴＩＦＩＣＩＡＬＷＡＴＥＲ－ＣＯＮＳＵＭＰＴＩＯＮ￥ＰｅｎｇＭｉｎ（彭敏）ＣｈｅｎＧｕｉｃｈｅｎ（陈桂琛）ＺｈｏｕＬｉｈｕａ（周立华）（Ｎｏｒｔｈｗｅ...     

Current Vegetation Pattern along Glacial Landscape in Central （Garhwal） Himalaya, India

Introduction High mountain ecosystems are comparatively thrilling and sensitive at least at the upper elevation levels, and are determined by abiotic climate related ecological factors. Therefore, the ecosystems at the low temperature limits of plant life are generally considered to be particularly sensitive to climate changes (Koerner 1999). As temperature is a key factor for high mountain plants (Koerner and Larcher 1988, Gottfried et al. 1998), an upward migration of species must be conse…     

BASIC FEATURES OF FOREST STEPPE IN THE LOESS PLATEAU OF CHINA

ＢＡＳＩＣＦＥＡＴＵＲＥＳＯＦＦＯＲＥＳＴＳＴＥＰＰＥＩＮＴＨＥＬＯＥＳＳＰＬＡＴＥＡＵＯＦＣＨＩＮＡ￥ＺｈｕＺｈｉｃｈｅｎｇ（朱志诚）（ＤｅｐａｒｔｍｅｎｔｏｆＢｉｏｌｏｇｙ．ＮｏｒｔｈｗｅｓｔＵｎｉｖｅｒｓｉｔｙ，Ｘｉａｎ７１００６９，ＰＲＣ）Ａ...     

THE DISTRIBUTION PATTERNS OF BACTERIA,ATP AND THE RELATIONS WITH RESPIRATION RATES AND PHYTOPLANKTON IN THE CHANGJIANG ESTUARY AND ITS ADJACENT EAST CHINA SEA

Two cruises were conducted in January and July 1986 in the Changjiang (Yangtse River) Estuary and its adjacent East China Sea (30°45′ -32°00′N,121°00′-124°00′E). Direct epifluorescence counts of planktonic bacteria and determinations of ATP concentrations were made. Subsamples were taken for measurement of oxygen consumption rates and chlorophyll concentrations.Bacteria and ATP concentrations were higher in summer than in winter, highest in the river and the river mouth, and gradually lower offshore. The bacteria number was correlated positively with suspended matter, nitrates and oxygen consumption rates, and negatively with salinity.In winter bacteria were the main contributors of ATP and the main consumers of dissolved oxygen in the whole studied area. In summer two maxima of ATP were found along the salinity gradient. The first one which coincided with the peak of turbidity near the river mouth was attributed to bacte -ria, and the second which occurred in the waters with a salinity range be     

DISTRIBUTIONS OF CHEMICAL ELEMENTS WITH RELATION TO MAJOR WATER CIRCULATIONS IN THE CENTRAL AND NORTHERN PARTS OF THE TAIWAN STRAIT

Data obtained from a comprehensive multidisciplinary oceanographic survey in the central and northern parts of the Taiwan Strait, 24°20′-26°00′N, 118°45°-121°00′E by the Fujian Institute of Oceanology during the period May, 1983 through May, 1984, showed that the distributions of dissolved oxygen (DO), nitrate, dissolved inorganic phosphate and silicate concentrations here had obvious areal and seasonal characteristics that were mainly influenced by the seasonal circulation ofthree major water systems in the Taiwan Strait-- the Taiwan Strait Warm Water (TSWW), theZhejiang-Fujian Coastal Water (ZFCW), and the Northeastern Strait Warm Water (NESWW).     

Episodes of volcanic activity and their environmental effects in the Okinawa Trough during the last 150 ka

1 INTRODUCTIONA large-scale volcanic eruption can injectenormous amount of ash and dust into the atmos-phere, leading to local and short cooling due toshielding incoming radiation. During the past 2 to 3decades, accumulated evidence indicated thatlarge-scale volcano eruptions or series of volcanicactivity appears to coincide with climatologicaltransitions. For example, Robock (1979) indicatedthat volcanic eruptions played a role in forcing "Lit-tle Ice Age". Well-dated high-resolution co…     

Study on fluxes of CH4 emission from paddy fields in Changchun area

Little has been done in measurement and research of the flux of CH₄ emission from paddy fields in Changchun area, Jilin Province, China before 1994. So the purpose of the study is to offer available regional data of CH₄ emission flux and to discuss the factors which affect CH₄ emission from paddy fields. Experimental paddy fields are chosen using TM pictures respectively in Xinlicheng (43°49′N, 125°20′E) of the Yitong River’s and in Wanchang (43°44′10″N, 125°53′11″E) of the Yinma River’s alluvial plain. The fluxes of CH₄ emission from paddy fields are measured by the method of static chamber in Changchun area in 3 consecutive years. The research results show that the peak of CH₄ emission from paddy fields occurs during the booting stage. The mean fluxes of CH₄ emission are 7.056 mg/m(² · h) and 0.489 mg/(m² · h) in the paddy fields of flood and discontinuous irrigation respectively. The contrastive study holds that climate condition, the way of water management and fertilizer variation have significant influence on fluxes of CH₄ emission from paddy fields. The difference of climatic conditions causes the interannual change of the flux of CH₄ emission from paddy fields. In general, the flux of CH₄ emission from paddy fields of flood irrigation is greater than that from paddy fields of discontinuous irrigation. To change the way of water management perhaps in an available way to reduce CH₄ emission flux from paddy fields. Foundation item: Under the auspices of Jilin Commttee of Science and Technology (grant 963416 - 1), and Changchun Jingyuetan Remote Sensing Test Site of the Chinese Academy of Sciences (grant 9504). Biography: YAN Min-hua (1964 -), female, a native of Liaoning Province, master, associate professor. Her research interests include climate change, greenhouse gases and wetland climate.     

A preliminary study on quaternary glacial landforms in Mt.Ma’an

Mt.Ma’an (4288 m) is the highest mountain in the southwest edge of Sichuan Basin. It is situated to the south of the Dadu River. The geographic coordinates are: 28°58′N, 102°55′E. There are six peaks over 4000 m in elevation. Many quaternary glacial landforms in this mountain have been discovered. It’s a typical example of fossil glacial landform in the east China. Its glacial stages are the last glaciation (Q ₃ ³ ) and the neoglaciation (Q ₄ ³ ). Mt. Ma’an and Mt. Luoji (4359 m) are similar in the fossil glacial landforms, but there are still some differences between them. For example, the ratio between the direct difference and the minus difference is different.     

Response of internal waves to 2005 Typhoon Damrey over the northwestern shelf of the South China Sea

Continuous observation of sea water temperature and current was made at Wenchang Station (19°35′N, 112°E) in 2005. The data collected indicate vigorous internal waves of both short periods and tidal and near-inertial periods. The temperature and current time series during 18-30 September were examined to describe the upper ocean internal wave field response to Typhoon Damrey (0518). The strong wind associated with the typhoon, which passed over the sea area about 45 km south of Wenchang Sta- tion on 25 September, deepened the mixed layer depth remarkably. It decreased the mixed layer temperature while increasing the deep layer temperature, and intensified the near-inertial and high-frequency fluctuations of temperature and current. Power spectra of temperature and current time series indicate significant deviations from those obtained by using the deep ocean internal wave models characterized by a power law. The frequency spectra were dominated by three energetic bands: around the inertial frequency (7.75× 10-6 Hz), tidal frequencies (1.010-25 to 2.4×10-5 Hz), and between 1.4×10-4 and 8.3 × 10-4 Hz. Dividing the field data into three phases (before, during and after the typhoon), we found that the typhoon enhanced the kinetic energy in nearly all the frequency bands, es- pecially in the surface water. The passage of Damrey made a major contribution to the horizontal kinetic energy of the total surface current variances. The vertical energy density distribution, with its peak value at the surface, was an indication that the energy in- jected by the strong wind into the surface current could penetrate downward to the thermocline.     

Meridional distribution of 226Ra in the west pacific and the southern ocean surface waters

During the 13^th (1996–1997) and the 19^th (2002–2003) Chinese National Antarctica Research Expeditions, we collected 60 discrete surface seawater samples along the cruise from the Chanjiang River (Yangtze) estuary (30°59′S, 122°26′E) through Taiwan Strait, the South China Sea, and the Eastern Indian Ocean to Prydz Bay, Antarctica (69°10′S, 74°30′E), and analyzed them for the ²²⁶Ra specific activity. The ²²⁶Ra specific activity of the Chanjiang River estuary surface water (3.15 Bq/m³) was found to be the highest among all the surface samples because of the desorption of ²²⁶Ra from riverine particles. Between Chanjiang River estuary and 40°S, ²²⁶Ra specific activity was found to be relatively uniform with a mean value of 1.07 Bq/m³ (n = 19, SD = 0.14), similar to that of the open ocean. From 40°S to 65°S, ²²⁶Ra specific activity increased intensively, then decreased moderately further southwards. Near the Antarctic shore, it increased again, to 2.31 Bq/m³. This distribution was controlled by a combination of deep water upwelling, Southern Ocean fronts, water mixing and the continental ²²⁶Ra import. In Prydz Bay and the adjacent sea area, the mean ²²⁶Ra activity value was 2.26 Bq/m³ (n = 31, SD = 0.28), with a relatively higher value outside of the bay and low ²²⁶Ra activity value in the center of the bay. This was consistent with the topography and hydrological setting of the bay. In addition, we extended the study area northward to the Arctic, by combining the published ²²⁶Ra dataset for surface water from the Bering Sea to the Japan Sea. We also discuss the ²²⁶Ra distribution of high latitude oceanic surface water and its mechanisms.