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The investigation of size-fractionated chlorophyll a and primary productivity were carried out in three longitudinal sections (63°-69°12′S, 70°30′E, 73°E and 75 (30′E) at December 18 -26, 1998 and January 12 -18, 1999 in Prydz Bay and its north sea area, Antarctica. The results showed that surface chlorophyll a concentration were 0.16 -3.99 μg dm-3 The high values of chlorophyll a concentration (more than 3.5 μg dm-3) were in Prydz Bay and in the west Ladies Bank. Tlie average chlorophyll a concentration at sub-surface layer was higher than that at surface layer; its concentration at the deeper layers of 50 m decreased with increasing depth and that at 200 m depth was only 0.01 -0.95 μg dm -3. The results of size-fractionated chlorophyll a showed that the contribution of the netplanktion to total chlorophyll a was 56%, those of the nanoplankton and the picoplankton were 24% and 20% respectively in the surveyed area. The potential primary productivity at the euphotic zone in the surveyed area was 0.11-11.67 mgC m h-1 and average value was 2.00 ±2.80 mgC-3h-1 The in-shu productivity in the bay and the continental shelf was higher and that in the dcep-sca area was lower. The assimilation number of photosynthesis was 1.53±1.11 mgC/ ( mg Chi a·h ). The results of size-fractionated primary productivity show that the contribution of the netplanlction to total produo tivity was 58%, those of the nanoplankton and the picoplankton were 26% and 16% respectively. The ceil abundance of phytoplankton was 1.6×103-164.8×103 cell dm-3 in the surface water.
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We describe a radio-echo sounding (RES) survey for the determination of ice thickness, subglacial topography and ice volume of Glacier No.1,in Tien Shan, China, using ground -penetrating radar (GPR). Radar data were collected with 100MHz antennas that were spaced at 4 m with a step size of 8 m. the images produced from radar survey clearly show the continuity of bedrock echoes and the undulation features of the bedrock surface. Radar results show that the maximum ice thickness of Glacier No.1 is 133 m, the thickness of the east branch of Glacier No.1 averages at 58.77 m while that of the west branch of Glacier No.1 averages at 44. 84 m. Calculation on ice volume indicates that the ice volume of the east branch of Glacier No.1 is 51.87 × 106 m3 and that of the west branch of Glacier No.1 is 20.21 × 106 m3. The amplitude of the undulation of the bedrock surface topography revealed by radar profiles is larger than that of the glacier surface topography, indicating that the surface relief does not directly depend on that of the bedrock undulation in Glacier No.1,in Tien Shan.
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A synthesis of Holocene pollen records from the Tibetan Plateau shows the history of vegetation and climatic changes during the Holocene. Palynological evidences from 24 cores/sections have been compiled and show that the vegetation shifted from subalpine/alpine conifer forest to subalpine/alpine evergreen sclerophyllous forest in the southeastern part of the plateau ; from alpine steppe to alpine desert in the central, western and northern part; and from alpine meadow to alpine steppe in the eastern and southern plateau regions during the Holocene. These records show that increases in precipitation began about 9 ka from the southeast and a wide ranging level of increased humidity developed over the entire of the plateau around 8-7 ka followed by aridity from 6 ka and a continuous drying over the plateau after 4-3 ka. The changes in Holocene climates of the plateau can be interpreted qualitatively as a response to orbital forcing and its secondary effects on the Indian Monsoon which expanded northwards during the early Holocene and retreated from the plateau since the mid-Holocene. Also there is teleconnection between the Tibetan Plateau and North Atlantic.
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The serum thyroid hormone and plasma catecholamine were examined in 18 male and 2 female members of the Chinese Antarctic Expedition (who spent the 2000 or 2001 austral winter at the Great Wall Station). The changes of serum thyroid hormone i. e. total thyroxine (TT4) and free T4 (FT4), total triodothyronine (TT3) and free T3 (FT3), thyroid stimulating hormone (TSH) and plasma catecholamine, including norepinephrine (NE), epinephrine (E) and dopamine (DA), were investigated by Chemoluminescence Immunoassay (CLIA) and High Performance Liquid Chromatography with electrochemical detection (HPLC-ECD). Samples were taken at different time: (1)1 day before departure to Antarctica (16th expedition 1999/12/ 09; 17th expedition 2000/12/06). (2) 1 day after returned to China after living 54 weeks in Antarctica (16th expedition 2000/12/25; 17th expedition 2001/12/25). Comparing the data of before departure and returned, results showed that there was a significant decrease in the contents of TT4 (P <0. 01) with no significant change in the content of TT3, FT3 and FT4. It was also found that the content of TSH increased significantly (P <0.001) ; No significant changes of plasma NE and DA were found but the content of E decreased significantly (P <0. 001). The results indicated that the special Antarctic environment led to a restrain effect on the thyroid function and the level of plasma E in Antarctic expedition members. Both the thyroid and adrenal medulla system were associated in response to the Antarctic systemic stress.
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The serum thyroid hormone and plasma catecholamine were examined in 18 male and 2 female members of the Chinese Antarctic Expedition (who spent the 2000 or 2001 austral winter at the Great Wall Station) . The changes of serum thyroid hormone i. e. total thyroxine (TT4) and free T4 (FT4) , total triodothyronine (TT3) and freeT3 ( FT3 ) , thyroid stimulating hormone (TSH) and plasma catecholamine, including norepinephrine (NE) , epinephrine (E) and dopamine (DA), were investigated by Chemoluminescence Immunoassay (CLIA) and High Performance Liquid Chromatography with electrochemical detection (HPLC-ECD) . Samples were taken at different time; (1)1 day before departure to Antarctica (16th expedition 1999/12/ 09; 17th expedition 2000/12/06). (2) 1 day after returned to China after living 54 weeks in Antarctica (16th expedition 2000/12/25 ; 17th expedition 2001/12/25 ). Comparing the data of before departure and returned, results showed that there was a significant decrease in the contents of TT4 (P <0. 01) with no significant change in the content of TT3 , FT3 and FT4. It was also found that the content of TSH increased significantly (P <0. 001) ; No significant changes of plasma NE and DA were found but the content of E decreased significantly ( P < 0. 001) . The results indicated that the special Antarctic environment led to a restrain effect on the thyroid function and the level of plasma E in Antarctic expedition members. Both the thyroid and adrenal medulla system were associated in response to the Antarctic systemic stress.
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We performed a comparison analysis of the variations.in Mercury (Hg) concentrations and the precipitation proxies (e. g., 18O values and 10 Be concentrations) in the Dome C ice core. The results showed that there were significant correlations between Hg and δ 18O values, 10 Be concentrations, indicating that the accumulation rate in Dome C is one of the key factors controlling the variations of Hg concentrations in the past 34, 000) years, and implying that Hg concentrations in ice core can be used as another reliable proxy of precipitation rate in Antarctica. Based upon the high-resolution δ18O values, we estimated the variations in mercury deposition flux to Antarctica over the past 34, 000 years. The highest mercury deposition flux is about 3.80 pg cm -2 yr -1 during the Last Glacia1 Maxium (LGM) as high as 3.5 times of the mercury deposition flux (about 1.08 pg cm -2 yr -1) in Holocene due to the fluctuations in natural mercury emissions such as the oceanic biological emissions.
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339 gas samples above oceanic surface were collected on the cruise of “ Xuelong” expeditionary ship and nitrous oxide concentrations were analyzed in the laboratory. Results showed that Atmospheric average N2O concentration was 309 ±3.8nL/L above the surface of northern Pacific and Arctic ocean. N2O concentrations were significantly different on the northbound and southbound track in the range of the same latitude, 308.0 ±3.5 nL/L from Shanghai harbor to the Arctic and 311.9 ±2.5 nL/L from the Arctic to Shanghai harbor. N2O concentration had a greater changing magnitude on the mid- and high-latitude oceanic surface of northern Pacific Ocean than in the other latitudinal ranges. The correlation between the concentrations of the compositions in the aerosol samples and atmospheric N2O showed that continental sources had a great contribution on atmospheric N2O concentration above the oceanic surface. Atmospheric N2O concentration significantly increased when the expeditionary ship approached Shanghai harbor. The average N2O concentrations were 315.1 ±2.5 nL/L, 307.2 ±1.4 nL/L and 306.2 ±0.7 nL/L, respectively, at Shanghai harbor, at icc stations and at floating ices. The distribution of N2O concentrations was related with air pressure and temperature above the mid- and high-latitude Pacific Ocean.
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Thirty-two meteorites were collected in Grove Mountains area, Antarctica, by the 15th and 16th Chinese Antarctic Research Expeditions (CHINARE). Petrog-raphy and mineral chemistry of these meteorites are reviewed, among which there are one Martian lherzolite, one eucrite, one ungrouped iron meteorite, and six unequilibrated and twenty-three equilibrated ordinary chondrites. An equilibrated ordinary chondrite GRV 98004 (H5) has an unusually low cosmic-ray exposure age. Meteorite concentrating processes in Grove Mountains area are discussed. In addition, future studies on Grove Mountains (GRV) meteorites are proposed.
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