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91.
Pavlova viridis sp. nov. is described on the basis of light and electron microscope observations. The material was collected from the coast
of haiyang county of Shandong, China. It is characterized by 1) yellowish green to green chloroplast, 2) rudimentary short
flagellum 0.3 μm long and hook-shaped, 3) long flagellum with small spherical knob-scales, 4) absence of pyrenoid and stigma,
and 5) marine habitat. This new species andP. salina seem to be most closely related to each other but their colour, the insertion of their three appendages, the shape of their
knob scales, and their cell periplasts are quite different from one another.
Contribution No. 1879 from the Institute of Oceanology, Academia Sinica 相似文献
92.
资源环境领域的信息化与本土化 总被引:2,自引:2,他引:0
陈述彭 《地球信息科学学报》2001,3(2):37-40
本文重点论述了资源环境领域的深层研究问题;同时提出用信息化推动现代化的观点,进而对地球信息科学与数字地球的战略进行了概要地分析。 相似文献
93.
For ecosystem modelling of the Boreal forest it is important to include processes associated with low soil temperature during spring‐early summer, as these affect the tree water uptake. The COUP model, a physically based SVAT model, was tested with 2 years of soil and snow physical measurements and sap flow measurements in a 70‐year‐old Scots pine stand in the boreal zone of northern Sweden. During the first year the extent and duration of soil frost was manipulated in the field. The model was successful in reproducing the timing of the soil warming after the snowmelt and frost thaw. A delayed soil warming, into the growing season, severely reduced the transpiration. We demonstrated the potential for considerable overestimation of transpiration by the model if the reduction of the trees' capacity to transpire due to low soil temperatures is not taken into account. We also demonstrated that the accumulated effect of aboveground conditions could be included when simulating the relationship between soil temperature and tree water uptake. This improved the estimated transpiration for the control plot and when soil warming was delayed into the growing season. The study illustrates the need of including antecedent conditions on root growth in the model in order to catch these effects on transpiration. The COUP model is a promising tool for predicting transpiration in high‐latitude stands. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
94.
This paper is a continuation of previous research, which obtained a convenient solution for arbitrary surface fluxes before ponding. By means of Fourier Transformation this has been extended to derive analytical solutions of a linearized Richards' equation for arbitrary input fluxes after surface saturation. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
95.
辽宁东、西部地质上诸多差异并非是原地升降运动造成的,而是二个异地岩块经郯庐断裂大规模左旋平移运动迁移到一起的结果。辽东半岛原曾与鲁西-徐淮地区处于相同的古纬度。郯庐断裂北延的主干断裂应是抚顺-敦化断裂,它在辽宁境内是地层区划的重要界线。郯庐断裂在太古宙末期即已出现,曾多次变换其平移方向,最近一次大规模左行平移活动的高峰期是在晚侏罗世晚期-早白垩世,结束于孙家湾组或泉头组堆积之前。 相似文献
96.
本文论述了土壤形成过程中应具有的一些质的特征,从而证明了流动砂丘并非属于土壤,而只是地质作用的非土形成物或成土母质。在此基础上,对流动砂丘上土壤的形成发育演变方向以及在土壤分类中的地位和命名等问题进行了探讨。 相似文献
97.
98.
青藏高原夏季地面有效辐射随高度的变化 总被引:1,自引:1,他引:0
根据1979年5-8月青藏高原热源观测资料,作者分析了高原上长波辐射随海拔高度的变化特点.地面辐射随海拔的的变化很缓慢,大气逆辐射随高度增高而很快减小,地面有效辐射在观测高度范围内(500米以下)则随着测点增高而增大.因此,如果将平原地区观测资料配合的计算有效辐射公式用于高原,其值将系统性偏低.为了表示平原与高原不同高度有效辐射的差别情况,作者根据观测资料求得了地面有效辐射与海拔高度的关系式. 相似文献
99.
100.
Summary. We present polarization diagrams of the particle motions at the free surface of an isotropic half-space generated by incident shear waves from a local buried point source. The reflectivity technique is used to calculate synthetic seismograms from which the particle motions are plotted. The particle motions are examined over a range of epicentral distances in a uniform isotropic half-space for different source frequencies and polarization angles, and for different Poisson's ratios. The particle motions due to a curved wavefront possess different characteristics from those generated by plane wavefronts at corresponding incidence angles. A curved wavefront generates a local SP -phase: a P -headwave which propagates along the free surface, and arrives shortly before the direct S -wave. These two arrivals give rise to cruciform particle motions in the sagittal and horizontal planes, which could be misinterpreted as anisotropy-induced shear-wave splitting. An examination of the particle motion in the transverse plane, mutually orthogonal to the sagittal and horizontal planes, can be used to discriminate between isotropic and anisotropic interpretations. The amplitude of the SP -phase is enhanced when it propagates in a low-velocity surface layer overlying the source layer, and may then become the dominant phase on radial-component seismograms. The presence of even a single surface layer may introduce considerable complexity into the seismogram, and we examine the effects of layer thickness, velocity contrast, and source depth on the corresponding polarization diagrams. Reliable information on the source and propagation path characteristics of shear waves from a buried local point source can only be obtained from free-surface records if they are recorded within a very limited epicentral distance range. 相似文献