陕西淳化圣人桥平缓盖层中复杂褶皱的成因——兼论重力滑动构造的分类

陕西圣人桥附近,复杂多样的褶皱出现在平缓的地台盖层之中。对其成因,争议颇多,或认为推覆作用所致,或认为受断裂作用控制。笔者通过详细研究,认为这些复杂褶皱是一种水底重力滑塌构造。据此,还提出了重力滑动构造新的分类,即重力蠕滑;重力滑塌以及重力滑碎等三类。     

Trace metal anomalies in bleached <Emphasis Type="Italic">Porites</Emphasis> coral at Meiji Reef,tropical South China Sea

Coral bleaching has generally been recognized as the main reason for tropical coral reef degradation, but there are few long-term records of coral bleaching events. In this study, trace metals including chromium (Cr), copper (Cu), molybdenum (Mo), manganese (Mn), lead (Pb), tin (Sn), titanium (Ti), vanadium (V), and yttrium (Y), were analyzed in two Porites corals collected from Meiji Reef in the tropical South China Sea (SCS) to assess differences in trace metal concentrations in bleached compared with unbleached coral growth bands. Ti, V, Cr, and Mo generally showed irregular fluctuations in both corals. Bleached layers contained high concentrations of Mn, Cu, Sn, and Pb. Unbleached layers showed moderately high concentrations of Mn and Cu only. The different distribution of trace metals in Porites may be attributable to different selectivity on the basis of vital utility or toxicity. Ti, V, Cr, and Mo are discriminated against by both coral polyps and zooxanthellae, but Mn, Cu, Sn, and Pb are accumulated by zooxanthellae and only Mn and Cu are accumulated by polyps as essential elements. The marked increase in Cu, Mn, Pb, and Sn are associated with bleaching processes, including mucus secretion, tissue retraction, and zooxanthellae expulsion and occlusion. Variation in these trace elements within the coral skeleton can be used as potential tracers of short-lived bleaching events.     

多氯联苯的环境特性及分析测试进展

由于多氯联苯(PCBs)在环境样品中残留浓度低,基质复杂干扰多,必须对环境样品进行预处理,并且结合先进的分析测试方法进行分析。文章综述了PCBs的性质及其主要来源;近年来分析PCBs的前处理方法,主要包括加速溶剂萃取、超临界流体萃取、微波萃取、固相微萃取、基质分散固相萃取等提取方法和固相萃取小柱、凝胶渗透色谱等净化方法;目前气相色谱和气相色谱-质谱联用技术发展以及一些新技术在分析PCBs方面的应用,包括全二维气相色谱法、快速气相色谱法、气相色谱-离子肼串联质谱法、高分辨气相色谱-高分辨质谱法等。总结了国内外PCBs的研究现状。     

Isozymes Analysis of the Golden Cuttlefish Sepia esculenta（Cephalopoda ： Sepiidae）

Thirty-nine isozymes in four tissues (mantle muscle, buccal bulb muscle, eye and liver) of Sepia esculenta were screened for enzymatic analysis using starch gel electrophoretic technique. Eighteen enzymes (G3PDH, LDH, MDH, MEP, IDHP, PGDH, GRS, NP, AAT, CK, AK, EST, ALP, ACP, FBP, MPI, GPI and PGM) show strong activities and good convergence in zymogram. They are proved to be suitable genetic markers in Sepia esculenta. Among the tissues used, mantle muscle is the best for electrophoretic analysis of isozymes. Eye and liver are fairly good for some special enzymes, such as LDH, EST, MPI, etc. Twenty-six loci are detected. The proportion of polymorphic loci is 0.115 in the Qingdao sample and 0.153 in the Rizhao sample (P<0.99). The mean values of the observed and expected heterozygosity per locus of Qingdao sample are 0.016 and 0.017, while those of the Rizhao sample are 0.023 and 0.025 respectively.     

Modeling the preservation potential of tidal flat sedimentary records,Jiangsu coast,eastern China

A forward modeling approach is proposed to simulate the preservation potential of tidal flat deposits. The preservation potential is expressed as a function of net deposition rate and a factor that represents the vertical flux of suspended load, or seabed lowering during erosion periods associated with bedload transport. The model takes into account a number of geometric parameters of a tidal flat sediment system and sediment dynamic processes. The former includes high water level, total sediment supply, the annual rate of the supply, the ratio of mud to bilk sediment in the supply, the bed slope of the tidal flat profile, as well as the slope of the stratigraphic boundary; the latter includes spring-neap cycles of tidal water level changes, boundary layer processes, resuspension of fine-grained sediments, bedload transport due to tidal currents, and bed elevation changes in response to sediment movement. Using this model, numerical experiments are carried out for a tidal flat system on the Jiangsu coast, eastern China, with the input data being derived from literature and from a series of sediment cores collected along an onshore–offshore transect. The results show that the preservation potential is highest over the upper part of the inter-tidal zone and in the lower part of the sub-tidal zone, and lowest near mean sea level and at low water on springs. The preservation potential tends to decrease with the advancement of the shoreline. The bed slope, tidal current direction and resuspension intensity influence the spatial distributions of the preservation potential. An implication of these results is that the temporal resolution of the tidal flat record depends upon the location and depth within the deposit; this should be taken into account in the interpretation of sedimentary records. Further studies are required to improve the model, on the hydrodynamic processes associated with extremely shallow water depths, sediment dynamic modeling of bed slope and profile shape, and the combined action of tides and waves for sediment transport on tidal flats.     

所有者与管理者其实可以上下分开——自然资源资产管理体制改革新设想

中央决策自然资源资产管理体制改革要所有者与管理者分开,但多数专家将其理解为所有者与管理者平面分开,并以其为理念设计自然资源管理体制.这种同一层次的分开将会造成自然资源管理体制改革只变体制不变机制,改革实施的指导思想出现矛盾.而所有者与管理者可以上下层次分开,中央部门和大区域管理机构共同组成所有者决策自然资源的保护与开发利用,地方自然资源部门作为管理者执行自然资源的保护、防治、修复、监管等职能.这种分法符合公共管理决策者和执行者分离的理论,有利于解决地方政府在自然资源方面的利益纠葛.     

EQUILIBRIUM COASTAL PROFILES:Ⅱ. EVIDENCE FROM EOF ANALYSIS

IamODUCTIoNInoIdertoestablishtheconceptofeqUilibriumforbeachprofiles,anuInberofproh-lemsmustbesolved,including:(i)pndoftheealstehceofeqUilibrium;(ii)definitionoftheshapeofaneqUilibriumcOaStalprofile;and(iii)evaluationofthePeriodoftimere-qUiredtoreachtheeqUilibritunstate(knownastheresPOnsetime).Forthefirstoftheseprohlems,areviewofpreviousinvestigationsandaSynhesisarepresentedelsewhere(GaoandCollins,1998).Accowhngtosuchtheoreticalconsidera-tions,threetwrsofeqUilibriurnInayoccurinnatllT…     

����任��ĸ�˹ͶӰ�������㷨

?о?????任???????????????????????????SuperCoor????????????????????????任??????????????????????????????ε??????3??????任?????????￡??????????????????     

Performance of four sea surface temperature assimilation schemes in the South China Sea

Four existing sea surface temperature (SST) assimilation schemes are evaluated in terms of their performances in assimilating the advanced very high resolution radiometer pathfinder best SST data in the South China Sea using the Princeton Ocean Model. Schemes 1 and 2 project SST directly to subsurface according to model-based correlations between SST and subsurface temperature. The difference between these two schemes is related to the order of vertical projection and horizontal optimal interpolation (OI). In Scheme 1, the spatially non-uniform SST observations are first projected to subsurface levels, followed by horizontal OI at each level. While in Scheme 2, the remotely sensed SSTs are first optimally interpolated to all grid points at the surface, followed by projecting gridded SSTs to subsurface levels. Scheme 3 assumes that the mixed layer is well mixed and has a uniform temperature vertically. In Scheme 4, SST is propagated to subsurface levels using a linear relationship of temperature between any two neighboring depths (Scheme 4a) or between surface and subsurface (Scheme 4b), which is derived by empirical orthogonal function (EOF) technique. To verify the results of the four schemes, the authors use the hydrographic data from two cruises during the South China Sea Monsoon Experiment in April and June 1998. It was shown that all four schemes could improve the SST field by reducing about 50% of the root mean square errors (RMSEs). All but Scheme 3 can improve model thermocline structure that is too diffused otherwise, though the RMSEs increase in the thermocline, especially for Scheme 2 when the model has opposite bias between upper layers and lower layers. Scheme 3 fails in the subsurface depth by increasing the thermocline depth, especially when there is a cold model bias. Projecting SST downward by EOF technique can deepen the depth of assimilation especially in Scheme 4a. Both Schemes 4a and b can correct the bias in the mixed layer and do not change the vertical thermal structure.     

镇安二台子金矿控矿规律研究与盲矿体预测

在总结二台子金矿成矿规律的基础上,采用信息量和特征分析方法对矿区及外围进行了综合预测.之后,运用地球化学与构造应力分析相结合方法,对已知矿体进行了深部预测并定位.