天津地面沉降区土水比论述

天津市地面沉降分布广,沉降速率大。本文针对当前地面沉降研究和防治过程中所遇到的勘查资料严重缺乏、禁采难以全面实现等难题,提出了土水比指标量。通过概念分析和对多年数据的分析,认为土水比可以检验地下水开采量数据的统计精度,指示地下水资源补给及土层释水条件,并表明沉降的严重程度,反映地下水资源的保障程度。建议在沉降防治工作中,以土水比作为指标,通过相关分析模型来制定压采量。     

Diel Patterns in Chlorophyll <Emphasis Type="Italic">a</Emphasis> Specific Absorption Coefficient and Absorption Efficiency Factor of Picoplankton

Diel patterns in the chlorophyll a specific absorption coefficient of surface picoplankton, a*_pico (γ) (m²·[mg chlorophyll a]⁻¹), were studied at 7 stations under daily cycle of in situ light condition in the western subarctic Pacific and Japan Sea. All the data were normalized by dividing the anomaly with daily averaged a*_pico (γ). Opposite diel patterns were observed for the normalized a*_pico (443) and a*_pico (675) with maximum toward dawn or dusk and minimum toward midday at 4 stations under low-irradiance (LI) conditions and vice versa at 3 stations under high-irradiance (HI) conditions. The absorption efficiency factors at red absorption peak, Q _a (675), were determined by reconstruction with intracellular chlorophyll a concentration and cell diameter. The normalized Q _a (675) also showed diel pattern with maximum toward midday and minimum toward dawn or dusk under LI. The diel pattern in a*_pico (675) and Q _a (675) were primarily caused by changes in intracellular chlorophyll a concentration due to photoadaptation under LI. The diel pattern in a*_pico (443) was influenced by pigmentation, as recognized by blue to red ratio [a*_pico (443)/a*_pico (675)] under HI. This study proposed that the opposite diel pattern in a*_pico (γ) might occur for a wide range of algal species. The results presented here have important consequences for the interpretation of diel variations in optical properties observed in the open ocean.     

南海大鹏湾夜光藻种群在其生态群落中的地位和功能

分析了１９９１年上半年南海大鹏湾盐田水域夜光菏和浮游动、植物之间的种群动态关系，结果表明，在春季高峰期３月至５月初，调查海域共出现１２个夜光藻和浮游动、植物高峰。其中，以发生４次赤潮的夜光藻种群占主导地位，其次是枝角类的鸟啄尖头蚤，其最高数量高达９６２３８ｉｎｄ／ｍ＾３。相比之下，在夜光藻和枝角类岛啄尖头捕食压力的影响下，浮游植物的春季高峰并不显著。调查结果表明夜光藻的过度繁殖，不但对产浮游性卵的     

Application of Monte-Carlo statistical experiments in design of ocean engineering——Estimating the parameters, models and probabilities

Recently, some results have been acquired with the Monte- Carlo statistical experiments in the design of ocean en gineering. The results show that Monte-Carlo statistical experiments can be widely used in estimating the parameters of wave statistical distributions, checking the probability model of the long- term wave extreme value distribution under a typhoon condition and calculating the failure probability of the ocean platforms.     

CO<Subscript>2</Subscript> Flux Measurements over the Sea Surface by Eddy Correlation and Aerodynamic Techniques

The measurements of the vertical transport of CO₂ were carried out over the Sea of Japan using the specially designed pier of Kyoto University on September 20 to 22, 2000. CO₂ fluxes were measured by the eddy correlation and aerodynamic techniques. Both techniques showed comparable CO₂ fluxes during sea breeze conditions: −0.001 to −0.08 mg m⁻²s⁻¹ with the mean of −0.05 mg m⁻²s⁻¹. This means that the measuring site satisfies the fetch requirement for meteorological observations under sea breeze conditions. Moreover, the eddy diffusivity coefficient used in the aerodynamic technique is found to be consistent with the coefficient used in the eddy correlation technique. The present result leads us to conclude that the aerodynamic technique may be applicable to underway CO₂ flux measurements over the ocean and may be used in place of the bulk technique. The important point is the need to maintain a measuring accuracy of CO₂ concentration difference of the order of 0.1 ppmv on the research vessels or the buoys.     

Deformation Patterns of an Accretionary Wedge in the Transition Zone from Subduction to Collision Offshore Southwestern Taiwan

Swath bathymetry data and seismic reflection profiles have been used to investigate details of the deformation pattern in the area offshore southwestern Taiwan where the Luzon subduction complex encroaches on the passive Chinese continental margin. Distinctive fold-and-thrust structures of the convergent zone and horst-and-graben structures of the passive margin are separated by a deformation front that extends NNW-ward from the eastern edge of the Manila Trench to the foot of the continental slope. This deformation front gradually turns into a NNE–SSW trending direction across the continental slope and the Kaoping Shelf, and connects to the frontal thrusts of the mountain belt on land Taiwan. However, the complex Penghu submarine canyon system blurs the exact location of the deformation front and nature of many morphotectonic features offshore SW Taiwan. We suggest that the deformation front offshore SW Taiwan does not appear as a simple structural line, but is characterized by a series of N–S trending folds and thrusts that terminate sequentially in an en-echelon pattern across the passive Chinese continental slope. A number of NE–SW trending lineaments cut across the fold-and-thrust structures of the frontal accretionary wedge and exhibit prominent dextral displacement indicative of the lateral expulsion of SW Taiwan. One of the prominent lineaments, named the Yung-An lineament, forms the southeastern boundary of the upper part of the Penghu submarine canyon, and has conspicuous influence over the drainage pattern of the canyon     

Seasonal and Spatial Variations of Total Mass Flux around Coral Reefs in the Southern Ryukyus,Japan

Total mass flux, size distribution of sediment particles and some chemical components such as total carbon (TC), total nitrogen (TN) and calcium carbonate (CaCO₃) were monitored monthly using a multi-cup sediment traps at seven coral reef sites (6 reef flat and 1 reef slope) of the Marine Protected Areas around Ishigaki, Kohama, Kuroshima and Iriomote Islands in the southern Ryukyus, Japan from September 2000 to September 2001. The size distribution of trapped sediments revealed mostly uni-modal fine sand to mud in the reef flat and gravelly to coarse sand in the reef slope. The total mass flux ranged between 0.54 to 872 gm⁻²d⁻¹, and showed a pronounced seasonality (high in summer-autumn and low in spring) at each site, which was consistent with the rainfall and typhoon regime. Exceptionally high values were observed on the reef slope (Iriomote) in February–March 2001 (1533 gm⁻²d⁻¹) owing to a large amount of bottom sediment re-suspension. On the reef flat (Todoroki South and North; Ishigaki), values obtained in July–August 2001 (872 gm⁻²d⁻¹) and August–September 2001 (800 gm^{− 2}d⁻¹) indicate the high terrestrial discharge from Todoroki River. Trapped sediment particles consist of CaCO₃ (1.2–27.1%) and a non-carbonate fraction (98.8–72.9%), which contains total carbon (4.9–26%), carbonate carbon (CO₂-C) (0.2–3.1%) and non-carbonate carbon (NC-C) (7.9–25.6%). Total nitrogen content was in the range 0.02–0.48%. TN is contained mainly in the carbonate fraction and NC-C may be contained in the non-carbonate fraction. The low TN/OC ratio of the trapped sediments suggests that they were mostly of terrestrial origin and that both fractions migrated. The high total mass flux derived from Todoroki River exceeded the threshold at which a lethal effect on coral community is caused. The results stress the importance of conducting seasonal studies of sedimentation over more than one year and at more than one location in south Japan coral reef ecosystems to gain an understanding of the processes controlling the total mass fluxes and their nutrients content, also to develop an awareness of how to prevent the damage of coral reef ecosystems and, if it does occur, to allow mitigation measures to be undertaken.     

真鲷的营养需要及配合饲料的研究初报

本文综述了真鲷的营养需要，研究了不同植物蛋白源对真鲷生长的影响，并在此基础上设计了三种饲料配方，试验结果表明Ｉ号饲料配方的增长率最高。     

海水中砷标准物质的研制

本文介绍了海水中砷标准物质的研制过程，其中包括溶液的配制、均匀性和稳定性检验，标样的分析方法。并对标准物质的定值数据进行统计处理，两种浓度的定值结果分别为：１．００μｇ／ｃｍ３±０．０４μｇ／ｃｍ３和５１．０μｇ／ｄｍ３±２．６μｇ／ｄｍ３。两种浓度砷标准物质的稳定期均为一年     

长江三角洲晚更新世末期古土壤与古环境

长江三角洲地区第一暗绿色硬粘土层是上海地区主要建筑持力层之一，也是划分全新统与更新统的标志层，前人已做过大量研究，但尚缺乏古土壤方面的系统研究工作。本文首次从古土壤学的角度系统研究了该层的古土壤特征，通过粒度分析发现有粘粒的生成，微形态研究发现有粘粒及铁锰、碳酸盐等化学组分的迁移与淀积，化学全量分析得出该层的硅铝率为２．８０～３．３７，说明该层已发生较强的成土作用，可以确认该层为古土壤层，并进一步把该层划分为４个Ｂ层、３个Ａ层，亦即该层为复合古土壤层。根据该层的成土特征，将其命名为古潮土