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EFFECT OF WATER FLOW ON LARVAL SETTLEMENT IN THE NAGURA AMPARU TIDAL LAGOON

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EFFECT OF WATER FLOW ON LARVAL SETTLEMENT IN THE NAGURA AMPA...

QUASI-3D SOLVER OF MEANDERING RIVER FLOWS BY CIP-SOROBAN SCHEME IN CYLINDRICAL COORDINATES WITH SUPPORT OF BOUNDARY FITTED COORDINATE METHOD

16th IAHR-APD Congress and 3rd Symposium of IAHR-ISHS

作者： Atsushi Kawachi tadaharu ishikawa Tokyo Institute of Tecnology 4259 Nagatsuta-cho Midori-ku Yokohama Kanagawa Japan

This study analyses settlement process of megalopa, which is final stage of crab larva, on a tidal lagoon based on population sampling of juvenile crabs and numerical simulation of larval settlement. Population sampling was carried out 3 times in settlement period, detailed distribution of the juveniles were grasped. The observed results indicated many megalopae have settled down at around points of 0.2 meters elevation. In addition, it seemed that the positions where many juveniles inhabited are near stagnation point. Then, to grasp the relationship between larval settlement and flow field, numerical tracer chasing by 2-D Lagrangian model was conducted. This study brought up tractive force as settlement parameter of tracer. By comparison the distribution, the calculated result with considering tractive force agreed with the observed result. Additionally, the results in spring tide are more reasonable than neap and middle tides, thus, megalopae may reinvade to the lagoon and settle down in the spring tide practically.

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QUASI-3D SOLVER OF MEANDERING RIVER FLOWS BY CIP-SOROBAN SCH...

Meteorological Data Generation for the Numerical Simulation of Stratified Flow in the Joumine Reservoir, Tunisia

16th IAHR-APD Congress and 3rd Symposium of IAHR-ISHS

作者： Keisuke Yoshida tadaharu ishikawa Dr. Eng. Tokyo Institute of Technology Japan

A new numerical solver is developed for the quasi-3D flow model to simulate meandering river flows. This solver can investigate the flows in an arbitrary curved river channel, by means of the adaptive CIP-Soroban (CIP-S) scheme in a cylindrical coordinate system with support of a boundary fitted coordinate (BFC) system. Time development of water velocity in an advection phase is computed by the orthogonal curvilinear coordinate system without any transformation of the governing equations, whereas a non-advection phase such as the continuity equation is solved by the BFC method, so that the mass conservation is fully satisfied and the water level is accurately calculated. From the verification of this solver on the meandering virtual river flows compared with the original BFC method, it is shown that the proposed solver accurately predicts the main flow profile in the regularly curved section of the flows, and that the horizontal velocity vectors both at the free-surface and at the bottom are reasonably predicted with the effect of the secondary currents in the curved section of the virtual river with some tributary streams.

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Journal of Environmental Science and Engineering(B) 2014年第4期3卷 173-180页

作者： tadaharu ishikawa Kakeru Takahira Mingyang Wang Mitsuteru Irie Department of Environmental Science and Technology Tokyo Institute of Technology Yokohama 226-8502 Japan Central Nippon Expressway Company Limited Nagoya 460-0003 Japan The Alliance for Research on North Africa University of Tsukuba Tsukuba 305-8572 Japan

Dynamic numerical simulation of water conditions is useful for reservoir management. In remote semi-arid areas, however, meteorological and hydrological time-series data needed for computation are not frequently measured and must be obtained using other information. This paper presents a case study of data generation for the computation of thermal conditions in the Joumine Reservoir, Tunisia. Data from the Wind Finder web site and daily sunshine duration at the nearest weather stations were utilized to generate cloud cover and solar radiation data based on meteorological correlations obtained in Japan, which is located at the same latitude as Tunisia. A time series of inflow water temperature was estimated from air temperature using a numerical filter expressed as a linear second-order differential equation. A numerical simulation using a vertical 2-D (two-dimensional) turbulent flow model for a stratified water body with generated data successfully reproduced seasonal thermal conditions in the reservoir, which were monitored using a thermistor chain.

关键词：动态数值模拟数据生成气象站突尼斯水库分层流时间序列数据二阶微分方程

洪泛区湿地水面积遥感监测新方法研究——以向海自然保护区为例

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东北师大学报（自然科学版） 2006年第1期38卷 108-113页

作者：何春光崔丽娟石川忠晴盛连喜东北师范大学湿地生态与植被恢复重点实验室吉林长春130024 中国林业科学院湿地研究中心北京100091 东京工业大学大学院综合理工学研究科

洪泛区湿地不仅具有区域洪水调蓄的生态功能,而且为各类珍稀濒危水禽提供重要的栖息生境.因此,如何能够突破传统的观测手段,运用更新、更快、更准确的手段,对洪泛区湿地水面积进行测算,从而为决策者制定相应的政策提供科学的依据成为当... 详细信息

洪泛区湿地不仅具有区域洪水调蓄的生态功能,而且为各类珍稀濒危水禽提供重要的栖息生境.因此,如何能够突破传统的观测手段,运用更新、更快、更准确的手段,对洪泛区湿地水面积进行测算,从而为决策者制定相应的政策提供科学的依据成为当前湿地监测方法研究的一个重点.利用美国陆地卫星影像(Landsat-TM)数据,通过建立一种简单有效的湿地水面积信息提取指数,提取了霍林河下游洪泛区湿地的水面分布信息.结合地面常规观测获取的向海水库的水面积,验证了该指数的可靠性.结果显示了该指数在湿地水面积定量测算中的技术优势,为洪泛区湿地水资源的监测评价与可持续利用,以及湿地水禽生境的管理和保护,提供了更可靠的技术保证.

关键词：洪泛区湿地水面积遥感监测新方法向海自然保护区

Effects of Reed Rootstocks on Hydraulic Properties of Surface Soil in the Shuangtai Estuary Wetland, Northeast China

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Journal of Environmental Science and Engineering(A) 2015年第4期4卷 169-176页

作者： Qian Lin tadaharu ishikawa Ryosuke Akoh Fenglin Yang Shushen Zhang Department of Environmental Science and Technology Tokyo Institute of Technology Yokohama 226-8502 Japan School of Environmental and Biological Science Dalian University of Technology Dalian 116024 China

A set of field experiments was conducted to investigate the effects of reed rootstocks on hydraulic properties of surface soils in the Shuangtai Estuary Wetland, Northeast China. The soil particle size distribution and rootstock content were analyzed, and the vertical soil water profile was monitored by using a multisensory capacitance system. Hydraulic conductivity of the surface soil layer was estimated by in si-tu infiltration. The soil was silt loam with less sand; soil texture was consistent though the vertical profile, but bulk density was lower in the upper 20 cm, where the fine roots were concentrated. The surface soil moisture profile changed dynamically, and variation in vertically integrated soil moisture was consistent with observed precipitation and estimated evaporation. Infiltration capacity was 30 cm·d-1, much larger than typical hydraulic conductivity values for silt loam with less sand. These findings suggest that fine annual roots change the soil matrix and hydraulic conductivity in surface soils. A vertical one-dimensional water transport model was presented based on Richard"s equation. Model parameters were estimated from the soil analyses and literature data. The computation accurately reproduced the dynamic changes in moisture in surface soils containing large volumes of fine rootstock.

关键词：表层土壤水力特性河口湿地根茎芦苇东北中国水力传导系数

浅水型湖泊水温日成层现象的初步探讨——以太湖为例

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四川环境 2008年第3期27卷 45-48页

作者：张玉超钱新石川忠晴孔繁翔南京大学环境学院污染控制与资源化研究国家重点实验室南京210093 东京工业大学环境科学与工程专攻中国科学院南京地理与湖泊研究所南京210000

水温是湖泊环境研究中的重要物理参数之一。本文以典型浅水型湖泊———太湖为研究对象,根据连续定点监测资料,分析了太湖的水温结构及其影响因素,证明了日成层现象的存在,并从物理、化学和生物学角度论述了水温分层现象对湖泊水质的影响。

关键词：水温日成层太湖水质

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太湖水温分层现象的监测与分析

环境科学与管理 2008年第6期33卷 117-121页

作者：张玉超钱新钱瑜陆根法石川忠晴南京大学环境学院污染控制与资源化国家重点实验室江苏南京210093 东京工业大学大学院综合理工学研究科

水温是湖泊环境研究中的重要物理参数之一。湖泊中水温的状况及其分层现象将直接或间接的影响到湖库水环境中的各种物理、化学和生物过程。深水型湖泊的温度成层现象为众多学者所公认,也是研究热点之一,而浅水型湖泊的温度成层温差小、... 详细信息

水温是湖泊环境研究中的重要物理参数之一。湖泊中水温的状况及其分层现象将直接或间接的影响到湖库水环境中的各种物理、化学和生物过程。深水型湖泊的温度成层现象为众多学者所公认,也是研究热点之一,而浅水型湖泊的温度成层温差小、持续时间短,因此鲜有此方面的研究。本文以典型浅水湖泊??太湖为研究对象,根据现场近3个月的监测资料,分析了太湖的水温结构,证明了太湖水温日成层现象的存在,并对太湖日成层现象发生规律及其影响因素做了初步的探讨。

关键词：水温日成层太湖浅水湖泊