黄河流域水循环研究的进展和展望

总结了黄河流域水循环研究的进展,指出缺乏立足于水循环整体的机理过程的探讨及缺乏较成熟的流域水文模型是已有研究的不足。为能更好地模拟水文过程对各种作用力的响应,今后研究的方向将是建立既考虑垂向水分和能量传输(如降水,蒸发,感热),又考虑水平向的地表水分运动(汇流)和地下水基流过程的黄河流域的分布式水文模型。模型将结合遥感信息与地面资料,建立与区域大气环流模式(GCM)的接口,辅之以野外生态试验小区、径流试验场和室内试验的资料,以深入探索黄河流域水循环动力学机制     

埃尔塔宁小行星质量的下限估计

埃尔塔宁小行星是一颗２１５ 万年前在南太平洋撞击地球的小行星,它也是目前唯一的深海区与地球碰撞的小行星。根据埃尔塔宁号和Ｐｏｌａｒｓｔｅｒｎ 号海洋调查船在陨击海区勘查的小行星残骸分布密度,我们估计埃尔塔宁小行星质量为２ ．３ ×１０１３ｇ ,对应于它的直径为０ ．２３ 公里。这比Ｋｙｔｅ 等人（１９８８） 估计的质量小了１０ 倍,然而它更接近埃尔塔宁小行星撞击事件的实际情况,可以作为埃尔塔宁小行星质量下限和半径下限更合理的估计值。     

局部微分求积法的深水包络孤立波数值模拟

利用局部微分求积法(LDQ)对非线性薛定谔(Schr dinger)方程进行数值求解,分别模拟了单深水孤立波运动,同向双深水孤立波追赶碰撞耦合运动,高阶孤立波振动和孤立波的反射与透射现象,得到各情况下的数值结果。从数值模拟及图像中揭示非线性薛定谔方程的性质和特点,阐述深水孤立波形成的物理意义、运动方式和运动规律,分析在不同初值条件下波形的变化特点,验证了LDQ法对该类问题的有效性。     

环境规制视角下城市绿色创新时空演变及溢出效应

基于2005—2019年中国266个地级及以上城市的面板数据,采用SBM-DEA模型评价城市绿色创新水平,刻画城市绿色创新的空间演变格局,最后构建空间杜宾模型实证分析不同类型的环境规制视角下城市绿色创新的溢出效应。研究结果显示：(1)时序发展上,研究期内城市绿色创新呈现东部地区、中部地区、西部地区、东北地区依次减弱的态势,总体上表现为“双M”型波动上升趋势,未来具有较大的增长潜力;(2)空间演化上,城市绿色创新在空间分布格局上存在明显的区域异质性,整体表现为东部地区主导发展的特征;(3)城市绿色创新在正式环境规制视角下存在正向溢出效应,在非正式环境规制视角下未产生显著溢出效应。     

GENETIC DIVERSITY OF THE WILD AND REARED PSEUDOSCIAENA CROCEA

The genetic diversity of both wild and reared Pseudosciaena crocea (Richardson) col-lected from Guan-Jing-Yang in Ningde, China in May 1999 was investigated by random amplified poly-morphic DNA (RAPD) in the present study. The polymorphism and mean difference of the wild popula-tion as revealed by RAPD were 18.9% and 0.0960 respectively, and those of the reared stocks were rel-atively lower, with 16.7% in polymorphism and 0.0747 in mean difference. The genetic distance be-tween the two stocks was 0.0041. From the comprehensive investigation, the main reasons for the loss of genetic diversity were probably overilshing, small number of parents as broodstocks and the debatable arti-ficial ranching. Results from this study also showed that the large yellow croaker populations distributed along Fujian coastal waters including Guan-Jing-Yang still potentially wide genetic variability. It is sug-gested that genetic management and prevention should be scientifically conducted in order to maintain and improve the genetic diversity of the P. crocea population.     

北部湾沿海基本风压和阵风风压分析

利用北部湾沿海7个气象站建站至2008年最大风速资料,采用指数律风速廓线公式和"时次换算"方法订正最大风速,得到长年代10m高处10min平均年最大风速序列;采用极值I型分布估算北部湾沿海各地50年一遇最大风速,通过伯努利方程计算基本风压。结果表明:北部湾沿海的基本风压以涠洲岛最大,达1.13kN/m2;其次是东兴、北海,分别为0.59和0.58kN/m2;第三位是防城港和合浦,分别为0.49和0.47kN/m2;最小是防城和钦州,分别为0.39和0.33kN/m2,表明越靠近海的地方基本风压越大。利用建站至2008年的极大风速资料对北部湾沿海的阵风风压进行分析,发现阵风风压分布特点与基本风压相同,而且阵风风压比基本风压大,海岸区域的阵风风压约为基本风压的2倍,涠洲岛则是1.54倍。     

Distribution characteristics of delta reservoirs reshaped by bottom currents: A case study from the second member of the Yinggehai Formation in the DF1-1 gas field,Yinggehai Basin,South China Sea

The Dongfang1-1 gas field (DF1-1) in the Yinggehai Basin is currently the largest offshore self-developed gas field in China and is rich in oil and gas resources. The second member of the Pliocene Yinggehai Formation (YGHF) is the main gas-producing formation and is composed of various sedimentary types; however, a clear understanding of the sedimentary types and development patterns is lacking. Here, typical lithofacies, logging facies and seismic facies types and characteristics of the YGHF are identified based on high-precision 3D seismic data combined with drilling, logging, analysis and testing data. Based on 3D seismic interpretation and attribute analysis, the origin of high-amplitude reflections is clarified, and the main types and evolution characteristics of sedimentary facies are identified. Taking gas formation upper II (IIU) as an example, the plane distribution of the delta front and bottom current channel is determined; finally, a comprehensive sedimentary model of the YGHF second member is established. This second member is a shallowly buried “bright spot” gas reservoir with weak compaction. The velocity of sandstone is slightly lower than that of mudstone, and the reflection has medium amplitude when there is no gas. The velocity of sandstone decreases considerably after gas accumulation, resulting in an increase in the wave impedance difference and high-amplitude (bright spot) reflection between sandstone and mudstone; the range of high amplitudes is consistent with that of gas-bearing traps. The distribution of gas reservoirs is obviously controlled by dome-shaped diapir structural traps, and diapir faults are channels through which natural gas from underlying Miocene source rocks can enter traps. The study area is a delta front deposit developed on a shallow sea shelf. The lithologies of the reservoir are mainly composed of very fine sand and coarse silt, and a variety of sedimentary structural types reflect a shallow sea delta environment; upward thickening funnel type, strong toothed bell type and toothed funnel type logging facies are developed. In total, 4 stages of delta front sand bodies (corresponding to progradational reflection seismic facies) derived from the Red River and Blue River in Vietnam have developed in the second member of the YGHF; these sand bodies are dated to 1.5 Ma and correspond to four gas formations. During sedimentation, many bottom current channels (corresponding to channel fill seismic facies) formed, which interacted with the superposed progradational reflections. When the provenance supply was strong in the northwest, the area was dominated by a large set of delta front deposits. In the period of relative sea level rise, surface bottom currents parallel to the coastline were dominant, and undercutting erosion was obvious, forming multistage superimposed erosion troughs. Three large bottom current channels that developed in the late sedimentary period of gas formation IIU are the most typical.     

钻孔应变仪体应力灵敏系数的影响因素研究

分别计算了水泥弹性模量、水泥层厚度、钢筒厚度、岩石弹性模量等对钻孔应变仪体应力灵敏系数的影响,得出:1)在水泥弹性模量小于某个固定值时,体应力灵敏系数随水泥弹性模量的增大而增大,大于这个值时,体应力灵敏系数又随水泥的弹性模量增大而变小;2)当水泥层厚度比N<2时,体应力灵敏系数变化剧烈,受水泥层厚度影响较大;3)体应力灵敏系数随钢筒厚度及岩石弹性模量的增大而变小。     

厚壳贻贝(Mytilus coruscus)足丝蛋白mcofp3和mcofp6的cDNA克隆及序列分析

通过设计特异性引物,采用PCR扩增的方法对厚壳贻贝足腺细胞cDNA文库进行筛选,共克隆得到14条厚壳贻贝mcofp3的cDNA序列和8条mcofp6的cDNA序列,并对其基因序列及推导的氨基酸序列进行了序列比对和变异位点初步分析。结果表明,14条mcofp3cDNA序列分属于厚壳贻贝mcofp3家族的两个亚家族,其成熟肽序列变异相对活跃;而8条mcofp6 cDNA序列并无明显的亚家族划分,序列相对保守。本次实验所获得的mcofp cDNA序列初步显示了厚壳贻贝足丝蛋白家族基因的分子多样性,为将来深入了解厚壳贻贝足丝蛋白的分子多样性机制以及在此基础上开发相关的新型生物黏附剂奠定了基础。     

基于210Pb测年法的楚科奇海陆架北缘有机碳沉积通量研究

有机碳沉积作用在一定时间尺度上形成海洋碳汇作用的最终净效应,北冰洋陆架的有机碳沉积作用在全球碳循环中有着尤为重要的地位。为了测定楚科奇海陆架的有机碳沉积通量,本文应用210Pb测年法对中国第3次北极考察R17站位的沉积物样品的年龄及沉积速率进行了分析测定,并结合表层沉积物中有机碳的含量计算得到了楚科奇海陆架北缘的有机碳沉积通量。结果显示,该站位的沉积速率为0.6 mm/a,表观沉积质量通量为0.72 kg/m2/a,有机碳沉积通量为517 mmol C/m2/a。经估算,真光层输出的有机碳中约有29 %被长期封存在沉积物中,远高于中低纬度的正常值（~10 %）,说明楚科奇海陆架区具有高效的碳汇作用。