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951.
952.
Diatom data of 192 surface sediment samples from the marginal seas in the western Pacific together with modern summer and winter sea surface temperature and salinity data were analyzed.The results of canonical correspondence analysis show that summer sea-surface salinity(SSS) is highly positively correlated with winter SSS and so is summer sea-surface temperature(SST) with winter SST.The correlations between SSSs and SSTs are less positively correlated,which may be due to interactions of regional current pa... 相似文献
953.
????????????????????????????????????????????????SymletС?????????о?????????????????????????????????????, ???????????4???5??????????????????????????????????????2???3????????????????????????????????????????????ε????????????????ο??? 相似文献
954.
利用冀鲁豫测网的流动重力5期观测成果,探讨了重力场变化与封丘地震的关系。研究发现:冀鲁豫交界地区的重力点值在封丘地震前后出现了下降-上升-下降的变化过程,较好地对应了封丘ML4.8地震孕育 发震 震后调整的过程。该重力变化可能是封丘地震的异常反映。 相似文献
955.
耿达短水准异常与汶川8.0级地震 总被引:2,自引:1,他引:1
结合龙门山断裂带其他跨断层资料,对耿达短水准在汶川8.0级地震前后的观测资料进行了重新分析,发现耿达短水准在汶川地震前后的异常为当地居民修建生活小区所致,不应视为地震前兆异常。 相似文献
956.
Global sea level change and thermal contribution 总被引:4,自引:0,他引:4
The global long-term sea level trend is obtained from the analysis of tide gauge data and TOPEX/Poseidon data. The linear trend of global mean sea level is highly non-umiform spatially, with an average rate of 2.2 mm year-1 in T/P sea-level rise from October 1992 to September 2002. Sea level change duc to temperature vanation (the thermosteric sea level) is discussed. The results are compared with TOPEX/Poseidon altimeter data in the same temporal span at different spatial scales. It is indicated that the ther-mal effect accounts for 86% and 73% of the observed seasonal variability in the northern and southern hemispheres, respectively. The TOPEX/Poseidon observed sea level lags behind the TSI, by 2 months in the zonal band of 40°-60° in both the northern and southern hemispheres. Systematic differences of about 1-2cm between TOPEX/Poseidon observations and thermosteric sea level data are obtained. The potential causes for these differences include water exchange among the atmosphere, land, and oceans, and some pos-sible deviations in thermosteric contribution estimates and geophysical corrections to the TOPEX/Poseidon data. 相似文献
957.
通过对珊瑚矿田长营岭-龙门冲地区岩石地球化学测量,圈定了该区W、Sn、Cu、Zn、As、B、F等元素异常,原生晕严格受NE和NW两组断裂控制。综合评价认为处于长营岭钨锡矿带南延带的南风井多元素组合异常是矿异常,该异常明显地受NE(F9)断裂和NW(F10)断裂控制,浓集中心位于F9断裂下盘,与长营岭矿区矿体在NW断裂下盘富集的规律相同。测区内,异常形态与北区具连续性,异常强度弱于北区,组分分带显示以隐伏花岗岩为成矿中心,但沿矿带由NE到SW并无明显的组分分带和元素组合变化,矿田内不仅矿带南延并向SW方向倾伏,而且很有可能深部隐伏花岗岩体亦分枝向南延伸。 相似文献
958.
脂肪水平对厚唇弱棘鯻生长及肠道脂肪酶活性的影响 总被引:1,自引:0,他引:1
以鱼油为脂肪源,配制成脂肪水平(质量分数,下同)分别为3.1%、5.8%、9.4%、11.9%和15.1%的5种等氮饲料,探讨饲料脂肪水平对初始体重为(4.05±0.11)g的厚唇弱棘鯻(Hephaestus fuliginosus)生长及肠道脂肪酶活性的影响。结果表明,随着饲料脂肪含量提高,实验用鱼脏体比、肥满度及肌肉粗蛋白含量也随着提高,但各组间差异不显著(P>0.05)。饲料脂肪水平从3.1%增加到9.4%,厚唇弱棘鯻的饲料效率呈升高趋势,相对增重率值由76.42%±5.88%升至102.09%±5.31%;而当饲料脂肪水平从9.4%提高至15.1%,饲料效率呈降低趋势(P<0.05),相对增重率值降为70.54%±2.06%。随着饲料脂肪水平提高,厚唇弱棘鯻肝体比、肌肉粗脂肪含量、肠道脂肪酶活性均呈上升趋势,且各组间差异显著(P<0.05)。表明本实验条件下饲料脂肪含量超过9.4%可导致厚唇弱棘鯻生长和饲料利用下降,对其形体特征、肌肉粗脂肪含量以及肠道脂肪酶活性均有显著影响。 相似文献
959.
Three ship-based observational campaigns were conducted to survey sea ice and snow in Prydz Bay and the surrounding waters(64.40°S–69.40°S, 76.11°E–81.29°E) from 28 November 2012 to 3 February 2013. In this paper, we present the sea ice extent and its variation, and the ice and snow thickness distributions and their variations with time in the observed zone. In the pack ice zone, the southern edge of the pack ice changed little, whereas the northern edge retreated significantly during the two earlier observation periods. Compared with the pack ice, the fast ice exhibited a significantly slower variation in extent with its northernmost edge retreating southwards by 6.7 km at a rate of 0.37 km?d-1. Generally, ice showed an increment in thickness with increasing latitude from the end of November to the middle of December. Ice and snow thickness followed an approximate normal distribution during the two earlier observations(79.7±28.9 cm, 79.1±19.1 cm for ice thickness, and 11.6±6.1 cm, 9.6±3.4 cm for snow thickness, respectively), and the distribution tended to be more concentrated in mid-December than in late November. The expected value of ice thickness decreased by 0.6 cm, whereas that of snow thickness decreased by 2 cm from 28 November to 18 December 2012. Ice thickness distribution showed no obvious regularity between 31 January and 3 February, 2013. 相似文献
960.
Status of the Recent Declining of Arctic Sea Ice Studies 总被引:2,自引:0,他引:2
In the past 30 years, a large-scale change occurred in the Arctic climatic system, which had never been observed before 1980s. At the same time, the Arctic sea ice experienced a special evolution with more and more rapidly dramatic declining. In this circumstance, the Arctic sea ice became a new focus of the Arctic research. The recent advancements about abrupt change of the Arctic sea ice are reviewed in this paper .The previous analyses have demonstrated the accelerated declining trend of Arctic sea ice extent in the past 30 years, based on in-situ and satellite-based observations of atmosphere, as well as the results of global and regional climate simulations. Especially in summer, the rate of decrease for the ice extents was above 10% per decade. In present paper, the evolution characteristics of the arctic sea ice and its possible cause are discussed in three aspects, i.e. the sea ice physical properties, the interaction process of sea ice, ocean and atmosphere and its response and feedback mechanism to global and arctic climate system. 相似文献