Authorship：Last author   Language：Japanese   Publishing type：Research paper (scientific journal)  

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Authorship：Last author   Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejj.23-16189

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Authorship：Last author   Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejj.23-16065

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejj.23-16063

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Authorship：Last author   Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejj.23-16143

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Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

In this study, we examine the possibility of proactive floodwater diversion to fields via backwater in numerical experiments using multiple elevation data products with different spatial resolutions and explore the optimal timing of water diversion from the perspective of crop calendars. This study targeted the Ida River System Land Improvement District, which has beneficiary lands on both banks of the Ida River, one of the tributaries of the Jinzu River that flows through Toyama and Gifu Prefectures in the Hokuriku and Chubu Regions of Japan. First, a comparison of the elevation data products revealed that photogrammetric data can capture microtopography, such as the footpaths between rice paddies and drainage channels around a field. Numerical experiments using two elevation data products, 5m DEM and LP-derived approximately 5m DEM, showed that flood peaks were reduced downstream in both cases using 5m DEM and LP approximately 5m DEM by directing floodwaters. Interviews with land improvement districts and a review of previous studies revealed that the ear-burst period is particularly vulnerable to flooding. Although the effect of flood peak reduction is reduced due to flooding of the field, it is possible that floodwater can be channeled during the ripening period in August and in late September and October when the ears have been harvested.

DOI： 10.3390/w15234139

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Hydrology and Water Resources  

DOI： 10.3178/hrl.17.77

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Language：Japanese  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

Abstract

In Thailand, floods are occurring more frequently due to climate change, and recent economic development and population growth may have altered the way in which people interact with floods, including migration to other regions. In this study, we analyzed the relationship between flooding and population distribution across Thailand from 2005 to 2019 to improve measures for minimizing flood damage. We used population distribution point data from 2009 to 2019 produced by Oak Ridge National Laboratory to analyze trends in population movement and distribution, by examining whether population sizes were greater than, less than, or equal to estimated values in regions throughout Thailand. The results suggest that floods in 2011 and 2017 caused temporary migration to areas that were not inundated or to the metropolitan Bangkok area. Flood responses changed after the 2011 floods, which have been described as the worst flood in Thai history. Next, we examined the relationship between the number of regions with lower than estimated population and flood data for the previous year including precipitation, inundated area, and deaths caused by flooding. Inundation area had a significant impact on population decline, with correlation coefficients of 0.426 and 0.501 for the north and northeast, respectively. The number of deaths caused by flooding in a given year also led to a population decline in the following year. However, precipitation did not exhibit the same trend. Therefore, population demographics after floods have shown regional characteristics in recent years, with Thai people shifting from a flood-tolerance lifestyle to a flood-avoidance lifestyle, mainly in local urban areas and the metropolitan Bangkok area.

DOI： 10.1186/s40645-023-00569-9

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Other Link： https://link.springer.com/article/10.1186/s40645-023-00569-9/fulltext.html

Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Hydrology and Water Resources  

DOI： 10.3178/jjshwr.36.1756

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejj.23-27019

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Authorship：Last author   Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejj.23-27018

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Authorship：Last author   Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejj.23-27029

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Language：Japanese  

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J-GLOBAL

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J-GLOBAL

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Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Hydrology and Water Resources  

DOI： 10.3178/jjshwr.35.1725

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Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Hydrology and Water Resources  

DOI： 10.3178/hrl.16.67

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Language：Japanese  

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Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejer.78.5_i_317

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Publishing type：Research paper (scientific journal)   Publisher：Fuji Technology Press Ltd.  

This paper presents a case study comparing the latest algorithm version of Global Satellite Mapping of Precipitation (GSMaP) data with C-band and X-band Multi-Parameter (MP) radar as high-resolution rainfall data in terms of localized heavy rainfall events. The study also obliged us to clarify the spatial and temporal resolution of GSMaP data using high-accuracy ground-based radar, and evaluate the performance and reporting frequency of GSMaP satellites. The GSMaP_Gauge_RNL data with less than 70 mm/day of daily rainfall was similar to the data of both radars, but the GSMaP_Gauge_RNL data with over 70 mm/day of daily rainfall was not, and the calibration by rain-gauge data was poor. Furthermore, both direct/indirect observations by the Global Precipitation Measurement/Microwave Imager (GPM/GMI) and the frequency thereof (once or twice) significantly affected the difference between GPM/GMI data and C-band radar data when the daily rainfall was less than 70 mm/day and the hourly rainfall was less than 20 mm/h. Therefore, it is difficult for GSMaP_Gauge to accurately estimate localized heavy rainfall with high-density particle precipitation.

DOI： 10.20965/jdr.2021.p0786

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.geothermics.2021.102073

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.gsd.2021.100555

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

DOI： 10.1002/hyp.14005

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：IOP Publishing  

Abstract

Thailand plays a central economic and policy-making role in Southeast Asia. Although climate change adaptation is being mainstreamed in Thailand, a well-organized overview of the impacts of climate change and potential adaptation measures has been unavailable to date. Here we present a comprehensive review of climate-change impact studies that focused on the Thai water sector, based on a literature review of six sub-sectors: riverine hydrology, sediment erosion, coastal erosion, forest hydrology, agricultural hydrology, and urban hydrology. Our review examined the long-term availability of observational data, historical changes, projected changes in key variables, and the availability of economic assessments and their implications for adaptation actions. Although some basic hydrometeorological variables have been well monitored, specific historical changes due to climate change have seldom been detected. Furthermore, although numerous future projections have been proposed, the likely changes due to climate change remain unclear due to a general lack of systematic multi-model and multi-scenario assessments and limited spatiotemporal coverage of the study area. Several gaps in the research were identified, and ten research recommendations are presented. While the information contained herein contributes to state-of-the-art knowledge on the impact of climate change on the water sector in Thailand, it will also benefit other countries on the Indochina Peninsula with a similar climate.

DOI： 10.1088/1748-9326/abce80

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Other Link： https://iopscience.iop.org/article/10.1088/1748-9326/abce80/pdf

Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.76.1_153

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Language：Japanese   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Hydrology and Water Resources  

DOI： 10.3178/hrl.14.136

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Authorship：Lead author   Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Hydrology and Water Resources  

DOI： 10.3178/jjshwr.33.193

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Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：International Association for Hydro-Environment Engineering and Research (IAHR)  

Climate change is one of the most pressing threats to sustainable development across the globe. There are expected to have significant effects on water resources planning and management, especially in estuary areas. The objective of this study is to evaluate of the vulnerability and adaptability for water management in eastern Thailand. The model is developed using Mike11 software, and calibrated and validated by historical matching utilizing data for the period 2013-2014. The study covered the area from Kgt.3 station, Prachinburi Province to the river estuary at the Gulf of Thailand. The model was divided into two parts, hydrodynamic (HD) module and advection-dispersion (AD) module. Calibration of each part was done by adjusting its important coefficients. It was observed that the Manning's coefficient (n) and coefficient dispersion of mass were in the range of 0.025-0.035 and 100-1,400 m2/s, respectively. The results of comparison between models and observation data revealed order of forecasting error (R2) in the range of 0.88-0.99 for water level and 0.81-0.99 for salinity. For model application, the RCP2.6 and 8.5 scenarios from IPCC report were simulated, sea water level rising in the year of 2100 were 1.04 and 1.34 m, respectively. Maximum salinity at Bangkhanag regulator, Chachoengsao Province was 13.48-13.66 g/l, exceeding standard for raw, tap and agriculture water. The increased of salinity also affects the growth of plants in the estuaries areas. These studies note the importance of water demand management through formal or informal institutions, regulations, and other approaches to adapt to the impacts of climate change. Results of this study can be used as guidelines for the management of water resources and agriculture of the Bang Pakong River and Eastern Economic Corridor (EEC) areas, Thailand.

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：International Association for Hydro-Environment Engineering and Research (IAHR)  

Since August 2016, we have carried out more than two years of on-site observations and water quality analyses in the lower reaches of the Chao Phraya River in Thailand. The water quality characteristics were assessed based on automatically collected water quality and water level data, obtained from the Thai government. In addition to these results, we investigated changes in water quality by comparing our results to those of previously reported field observations and water quality analyses. According to our results, water quality characteristics vary significantly with the season due to changes in natural discharge in the rainy season and constant discharge by the Chao Phraya Dam during the dry season. In the dry season, the salinity intrusion range was larger, with high salinity, and the water had low temperatures and oxygen contents. During the rainy season, the salinity intrusion range was suppressed, and the water had low salinity, high temperature, and high oxygen contents. The longitudinal river pH was alkaline. Previously, the salinity of the water was high from the mouth of the river to a distance of 100 km downstream, and had a high oxygen content at distances from 150 to 350 km from the river mouth and low oxygen near the river mouth. The pH of the water was alkaline longitudinally along the river, with the value decreasing from upstream to downstream. There were no significant differences between the water quality characteristics detected in this study and those reported previously.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：FUJI TECHNOLOGY PRESS LTD  

The objectives of this study are to conduct an analysis on rainfall change tendencies, calculate the inundation in the basins of Mun and Chi Rivers in the northeastern region of Thailand, and clarify the flood risk in the long term, taking the spatial characteristics of flooding into consideration. To grasp the rainfall change tendencies, two statistical analyses are conducted using the Mann-Kendall test and the generalized extreme value distribution. The inundation analysis is conducted using the Rainfall-Runoff-Inundation (RRI) model. As a result of the statistical analysis on the rainfall characteristics, it can be observed that the annual rainfall has significant increasing tendencies at the significance level of 5% in a wide area of the upper reaches. In addition, inundation calculation indicates that the maximum inundation depth and inundation area have increased in recent years.

DOI： 10.20965/jdr.2019.p1337

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHULALONGKORN UNIV, FAC ENGINEERING  

We used a spatially interpolated gridded dataset produced by the Thai Meteorological Department (TMD) to explore long-term rainfall trends. We placed data from 1981-2017 into a 0.5 grid using the Kriging method. Long-term trends in maximum daily and monthly rainfall, and total annual rainfall, were analyzed using the nonparametric Mann Kendall trend test. Chumphon, Lamphun, Nakhon, Sawan, and Buriram provinces exhibited significant positive trends in the annual maximum daily rainfall (p<0.05, p<0.01). The coastal area of Chachoengsao Province exhibited a significant negative trend (p<0.05). January rainfall showed a negative trend throughout Thailand. Annual rainfall showed a positive trend in many regions, especially in northern, northeastern, and southern areas. The eastern region exhibited a negative trend but statistical significance was not attained. The 10-, 30-, 50-, and 100-year daily rainfall probabilities were estimated using the Generalized Extreme Value method. The eastern side of the southern region exhibited remarkably high rainfall

DOI： 10.4186/ej.2019.23.6.461

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER HEIDELBERG  

The supply of sediment to Ichkeul Lake has decreased due to the construction of several reservoirs in the upstream reaches of the rivers that flow into it. Furthermore, it is necessary to control lake sediment outflow in order to preserve the ecological balance of the lake. Soil stabilization methods could be used to prevent the erosion of bottom sediment. Therefore, this study explored the physical and mechanical condition of the lake bed in situ to aid the identification of an effective erosion prevention scheme based on solidification methods. Two locations on the lake bottom were investigated and compared: one where the sediment dried up in summer, and the other where the sediment was saturated with water throughout the year. Undisturbed samples were collected using a thin-walled stainless steel tube sampler. The shear strength and its depth distribution in the lake bed were measured using the vane shear test. The depth distributions of the shear strength at the two sampling locations studied were found to be rather different. The shear strength was highest in the surface layer at the location that was dry in summer, whereas the shear strength was lowest in the surface layer at the location that was always wet. The shear strength of the surface layer (20 mm depth) at the wet/dry location was 3.3 kPa and there was 93.1% moisture, while the shear strength at this depth at the permanently wet location was 1.8 kPa and there was 95.7% moisture. The strength of the wet/dry sediment, which underwent shrinkage when drying, was greater than that of the permanently wet sediment. This finding could facilitate the classification of areas that require soil improvement as well as the rational design of an erosion prevention plan.

DOI： 10.1007/s41207-019-0125-x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：FUJI TECHNOLOGY PRESS LTD  

A large scale flood disaster occurred in Southern Thailand in December, 2016 and January, 2017, resulting in 95 deaths. The majority of the 15 provinces in Southern Thailand suffered from the disaster and extensive, long-term damage was caused which distinguished this flood event from previous flood disasters. This paper reports the findings of a field survey conducted in February, 2017 and analyzes the precipitation phenomena by using ground rainfall data as well as satellite rainfall data because there were not enough ground rain gauges set in this region. Results revealed that this precipitation event had the highest intensity out of all precipitation events occurring over the last 11 years.

DOI： 10.20965/jdr.2018.p0793

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

When X-band MP radar has observed high intensity rainfall area, QPE(Quantitative Precipitation Estimation) of X-band MP radar(X-MP) can't often observe with high accuracy. In fact, QPE of X-MP has underestimated against Rain-gauge data and C-band radar data at JMA Asakura by heavy rain in the Northern-Kyushu region on July 2017. So, this study is to clarify observation characteristics of X-MP using this event such as including high intensity rainfall area. This study has used horizontal polarization (Zh) and specific differential phase shift(Kdp) as polarization parameter of X-MP.

DOI： 10.11520/jshwr.31.0_136

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Language：Japanese  

DOI： 10.3178/jjshwr.30.373

CiNii Books

J-GLOBAL

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Language：English   Publishing type：Research paper (scientific journal)  

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J-GLOBAL

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CiNii Books

J-GLOBAL

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

<p>&emsp;Rain-gauge stations have been operated by many agencies, but temporal and spatial characteristics of the rain-gauge network have not been studied sufficiently. We studied the observation system and some characteristics of the rain-gauge network throughout Japan using available observed data of the Japan Meteorological Agency (JMA), the Water and Disaster Management Bureau under the Ministry of Land, Infrastructure, Transport and Tourism (MLIT), and local governments (L-Gov).<br>&emsp;Analysis results obtained using available observed data show different installed characteristics of rain-gauge networks among L-Gov observation systems. The JMA rain-gauge network decreased to 58 rain-gauge stations during 2008-2014. Most abandoned rain-gauge stations shared common features: rain-gauge stations were installed at high altitude, with high observation and maintenance costs. Regarding historical stored rainfall data of rain-gauge networks, approximately 90 % of JMA and MLIT rain-gauge stations have less than a 40-year historical store of data, with no missing rainfall data (hourly, daily, and annual).</p>

DOI： 10.3178/jjshwr.30.43

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J-GLOBAL

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DOI： 10.2208/jscejer.73.I_149

J-GLOBAL

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DOI： 10.2208/jscejhe.73.I_235

J-GLOBAL

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DOI： 10.2208/jscejhe.73.I_67

J-GLOBAL

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DOI： 10.2208/jscejer.73.I_31

J-GLOBAL

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

Heavy snowfall is one of the natural disaster, and may seriously affect the human and social economic activity. So, we have to observed as snowfall data using some the observation method such as rain-gauge station, C-band radar, X-band Multi-Parameter radar and Global Satellite Mapping of Precipitation(GSMaP).<br />The purpose of this study is clarify to the observation characteristics using rain-gauge, C-band radar, X-band MP radar and GSMaP data during heavy snowfall. In particular GSMaP data, this study used GSMaP_MVK and GSMaP_Gauge.

DOI： 10.11520/jshwr.30.0_69

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

&emsp;The Uchikawa River (UR), located in the Hokuriku region of Japan, has water pollution and odor annoyance caused by a density current. The UR connects to the Toyama Bay at three points. Therefore, almost no flow takes place in this river. Moreover, details of the flow mechanisms of the UR are poorly understood. The UR stream regime was observed using the Acoustic Doppler Current Profiler (ADCP), which has supported simulation of the UR current mechanism using computational fluid dynamics analysis. First, ADCP observations revealed a backward current of all layers immediately before a saline wedge run up in the Western UR (WUR). Second, a simulation model was produced using the three-dimensional volume of fluid (VOF) method. Numerical analysis results show partial reproduction of the backward current of all layers.

DOI： 10.3178/jjshwr.29.251

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Language：English   Publisher：FUJI TECHNOLOGY PRESS LTD  

This article reports on the public forum conducted by the authors at the Third United Nations World Conference on Disaster Risk Reduction, held in Sendai City, Miyagi Prefecture, Japan, from March 14 to 18, 2015. The conference included case studies of recent water-related disasters in the Southeast Asia region, reviews of academic research, and a description of the current situation about measures for risk reduction. This article also clarifies the relationship between the various recommendations proposed in the public forum and the Sendai Framework for Disaster Risk Reduction 2015-2030 (the Sendai framework), in order to identify the efforts that are necessary for the implementation of the Sendai framework.

DOI： 10.20965/jdr.2016.p0394

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J-GLOBAL

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

We tried to know the&nbsp;rainfall characteristics in the<br>Nishi-Chugoku mountains in western Japan analyzing the long term and intensive observation<br>period data of stations (12 stations) of AMeDAS, Kitahiroshima town, and<br>Hiroshima University.&nbsp; As a result, we<br>obtained the following things:<br>1 The rainfall amount depends on the altitude and the geomorphological opening area ratio.<br>2 The drought year depends on the rainfall amounts in July and August.<br>3 The return period of the drought year was estimated to be within 10 years.<br>4 The higher altitude stations had the higher hourly rainfall intensity in a day.<br>5 There was no remarkable difference of the 10 minutes period rainfall among all the stations.&nbsp;<br>

DOI： 10.11520/jshwr.29.0_70

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

This study clarify water source in Kurobe River basin by multivariable analysis. Ten dissolved ions data were used for analyze characteristics of water in Kurobe River basin. AS a result Kurobe River basin showed 96.8% of characteristics until 4st principal component.

DOI： 10.11520/jshwr.29.0_98

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

The Chao Phraya River basin (CPRB) in Thailand had a massive flooding in 2011, which affected on not only Thai socio-economics but also global supply-chain of industrial production. &nbsp;In order to propose a new reservoir operation system on science-based which can be easily put into practice, we studied a reservoir optimum operation for Bhumibol reservoir in the CPRB. &nbsp; This paper proposed a new reservoir management method which is based on historical largest inflow and flow capacity of downstream. In this paper, the Using historical hydrological data, a usefulness of the new reservoir operation method was verified. As a result, only the operation which has biggest flood control capacity could control the flood in 2011. However, all validation cases were not able to obtain both flood control and maintaining irrigation capacity.<br>

DOI： 10.11520/jshwr.29.0_108

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

The areal rainfall using rain-gauge data have only to observed data by the rain-gauge station as point data.<br>However, for local rainfall, such as to pass a part of river basin, the areal rainfall using rain-gauge data may not be able to estimate high accuracy.<br>Although missing data of X-band Multi-Parameter radar have more than that of C-band radar, there are not to clarify affect the areal rainfall of that radar.<br>This study was compared the areal rainfall of rain-gauge data and radar data by local rainfall.<br>Moreover, this study also have clarify to the relationship between missing data of X-MP and difference value of C-band data and X-MP data.

DOI： 10.11520/jshwr.29.0_73

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

The Chao Phraya River basin (CPRB) in Thailand had a massive flooding in 2011, which affected on not only Thai socio-economics but also global supply-chain of industrial production. The Thai government is planning watershed management for the CPRB. In order to propose a new reservoir operation system on science-based which can be easily put into practice, we studied a reservoir optimum operation for Bhumibol and Sirikit reservoirs in the CPRB. This paper proposed the new reservoir operation method that daily release discharge were decided by using the day before storage volume data. A usefulness of the reservoir operation method was verified using historical hydrological data. As a result, the proposed reservoir operation method could contribute stabilization of storage volume.

DOI： 10.2208/jscejhe.71.I_1423

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Other Link： https://jlc.jst.go.jp/DN/JLC/20019957850?from=CiNii

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：ELSEVIER SCIENCE BV  

The parameter estimation (PEST) method was used to estimate the spatial distribution of permeability coefficients in a high-permeability area of the Kurobe River alluvial fan in Toyama Prefecture, Japan. We considered spatial resolution, estimated period, soil structure, recharge source, and boundary conditions in the model. Numerical experiments produced estimated permeability coefficients that were consistent with the observed data and those of previous studies under all conditions. However, the estimated groundwater levels were lower than those of previous studies. Spatial resolution and the number of foundation layers did not have a large effect on estimates of the vertical permeability coefficient (k(z)). However, recharge source and boundary conditions were important for estimating permeability coefficients. Finally, the estimates of specific storage (S-s) and specific yield (S-y) were similar to the observed data under all conditions. (C) 2015 Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license.

DOI： 10.1016/j.proenv.2015.04.032

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&emsp;This study was designed to clarify the accuracy of X-band multi-parameter radar (X-MP) over the Hokuriku region using rain gauge data and quantitative precipitation estimation (QPE) by C-band radar. Moreover, this study used results of the correlation coefficient and estimate error for QPE accuracy analysis.<br>&emsp;Temporal analysis revealed that X-MPs provide observation data with high accuracy for short-term downpours, but results for long-term and light rainfall or regions distant from the radar site were less accurate.<br>&emsp;Spatial analysis showed the X-MP data accuracy was observable with sufficient accuracy within a range of 2.25 × 2.25 km as the center of each rain gauge station. The X-MP data accuracy has less than the C-band radar data accuracy beyond a 20 km radius from the radar site.<br>&emsp;Quantitative analysis of the rainy season and snowy season, total precipitation of X-MP and C-band radar were overestimated from that of the rain gauge station, it was especially overestimated significantly during the snowy season.

DOI： 10.3178/jjshwr.28.221

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Language：English   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

&emsp;Most severe disasters have included extreme rainfall intensity. Consequently, it is necessary to develop rainfall observation technology that provides observations over a large area over a short-term, with high accuracy. This study was conducted to clarify the accuracy of X-band multi-parameter radar (X-MP) over the Hokuriku region using rain-gauge data collected by the Japan Meteorological Agency (JMA) and the Water and Disaster Management Bureau under the Ministry of Land, Infrastructure, Transport and Tourism (MLIT). Additionally, this study analyzed results in terms of installed altitudes of rain-gauge stations and distance from the radar site to the rain-gauge station.<br>&emsp;Results of statistical analyses show that the distance from the radar site engenders lower accuracy of the X-MP.However the X-MP data accuracy was equal to that of rain-gauge data within a 20 km radius from the radar site. Although the X-MPs provide observations with high accuracy for rainfall observation, snowfall observation was less accurate. Therefore,quantitative snowfall estimation might improve the observation accuracy of the X-MP. Examination of the Z-R relation and the K_DP-R relation shows that Z-R might provide better accuracy than K_DP-R beyond a 30 km radius from the radar site. Results suggest the necessity of using and analyzing more observation data.

DOI： 10.3178/jjshwr.27.67

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Language：Japanese   Publisher：Japanese Association of Groundwater Hydrology  

DOI： 10.5917/jagh.55.21

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

&nbsp;In recent years, water related disaster risks have increased all over the world, therefore both non-structural and structural measures for flood management have been carried out. However, it is difficult to take thorough measures; therefore appropriate watershed management is being reconsidered. The unregulated peak discharge that used as important value for watershed management especially flood management is calculated using historical heavy rainfall data. Quantity of rainfall data is more plenty than river discharge data, however the hyetograph need to extend for making design flood discharge and hydrologic model has uncertainty issues. This paper proposes a new making method for flood exceeding the designed level using waveform of historical flood discharge data. The Jinzu River basin was selected for this study, which is basis of social and economic in Toyama prefecture. As a result of numerical simulation, high flood risk area was clarified in this basin. Finally, the existing design flood discharge 9700 m³/s was 1/150 return period; however the value was 1/500 return period estimated using the GEV distribution in this study. As the result of comparison between 10 probability distribution functions, the calculated probable discharges had large differences.

DOI： 10.2208/jscejer.69.I_131

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Language：English   Publisher：Japan Society of Civil Engineers  

Climate changes induced by global warming are a worldwide concern. In some regions, the risk of serious floods is expected to increase under a changing climate during the 21st century. This study examined the potential impacts of climate change in the Chao Phraya River Basin (CPRB), Thailand, using the MRI-AGCM3.1 and 3.2 datasets, developed by the Meteorological Research Institute (MRI) of the Japan Meteorological Agency, as inputs to a watershed hydrologic model. The results indicated that future river discharges will increase owing to increased rainfall in the upper mountainous region and in the Nan, Yom, and Wang river basins. Furthermore, a significant increase in annual inflow to the Bhumibol reservoir was projected in the late 21st century, whereas drought conditions may occur in the Pasak River Basin in the future.

DOI： 10.2208/jscejhe.69.I_55

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

To understand the characteristics and seasonal changes in flowing artesian wells in the Kurobe River alluvial fan (KRAF), the discharge, water quality, and isotope ratio of 23 flowing wells were observed for 18 months from March 2011. This paper newly reports the monthly discharge and water quality of these flowing wells. Variation in water flow at 10-minute intervals is also presented. All wells exhibited the same seasonal changes, and no spatial difference in water quality was found. Analysis of isotope ratios indicated that three wells located on the left bank of the KRAF were recharged from difference sources than the other wells that were recharged by the Kurobe River. Comparison with previous water quality measurements taken 10 to 20 years ago showed that the water quality had not changed. However, further research is needed to clarify long-term trends of the flowing water discharges.

DOI： 10.2208/jscejhe.69.I_589

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

The Chao Phraya River basin, the largest basin in Thailand, is located in the centre of the northern part of the country. This basin has two large-scale reservoirs: the Bhumibol Reservoir on the Ping River and the Sirikit Reservoir on the Nan River. A comparison of the annual and monthly flow regimes downstream from the reservoirs before and after reservoir development showed a constant increase in low flow and a drastic decrease in high flow. The spectrum of the daily discharge was analysed using the fast Fourier transform on data collected in the area of Nakhon Sawan and immediately downstream from the Bhumibol Reservoir after the reservoir was constructed. The flow at Nakhon Sawan had a periodic characteristic of 7? days. The water released from the Bhumibol Reservoir at hydrological station P.12 also had a periodic characteristic of 7?days. Reservoir operations have a significant impact on the hydrological cycles. The effect of human activities is evident in the spectrum analysis of recorded historical discharge data. Copyright (C) 2012 John Wiley & Sons, Ltd.

DOI： 10.1002/hyp.9345

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Language：Japanese   Publishing type：Research paper (scientific journal)  

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

To clarify the spatial characteristics of rain-gauge network over Japan, we studied some characteristics of rain-gauge network over Japan using available data observed by the Japan Meteorological Agency (JMA), the Water and Disaster Management Bureau under the Ministry of Land, Infrastructure, Transport and Tourism (WDMB-MLIT) and Local Government (L-Gov). Additional spatial analysis was also used available digital national land information (DEM, topographical slop, land use, surface geology, major road, natural park). As a result of spatial analysis using some digital national land information and observation blank zone, more than altitude 500m area couldn't be installed rain-gauge stations. Some observation blank zones have been topographical slop were rich in ups and downs. Rain-gauge stations weren't installed in only limited land use or surface geology. Moreover, many rain-gauge stations tend to be installed near the major road. Therefore, some observation blank zones could install rain-gauge stations.

DOI： 10.2208/jscejhe.68.I_415

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

To grasp the temporal change of hydraulic phenomena in tidal area of the Uchikawa River during saltwater intrusion into the river, a long-term observation was carried out using the ADCP. As a result, detailed vertical velocity distributions of two-layer flows with salt-wedge type in tidal area of the Uchikawa River were observed. It was found that saline water with weakly-mixed type made intrusions into the Uchikawa River regardless of seasonal and/or tidal effects. Especially, time series of flow velocity had periodicities during salinity intrusion. Furthermore, flows in both upper and lower layers were laminar flow and showed F_d1&asymp;0.4 in the front part of saline wedge, and then turbulent flow zone within F_d1&le;0.4, 10⁴&le;Re_1,2&le;10⁵ was observed when fresh and saline two layers had been stable. It can be inferred from previous studies that it is possible to estimate the interfacial resistance coefficient fi using the proposed Iwasaki number &phi; function for the tidal area of the Uchikawa River.

DOI： 10.2208/jscejhe.68.I_1327

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

To clarify the present situation of water environment in the Uchikawa River in Toyama, field observations (water quality, flow velocity distribution and plankton sampling) have been carried out continually since 2009. Water quality in the Uchikawa River had been aggravated due to the development of well-drained paddy fields and new ports in and around the river basin from 1960s. Regardless of a water reclamation program, water quality in the Uchikawa River does not show a drastic improvement.Due to the effect of purification water from the Nishi-Uchikawa River, upward flows of seawater and vertical water quality changes in the Higashi-Uchikawa River were found from the investigation results of water quality. It was also found that the spatial distribution of plankton was influenced by the water flows. The existence of both freshwater and marine (brackish) algae in the river indicates that the resources subsidizing food web are provided through the multi-directional water flow.

DOI： 10.2208/jscejhe.67.I_1663

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

Rain-gauge stations have been operated by many agencies, thus temporal and spatial characteristics of rain-gauge network have not been studied. We studied the observation density of rain-gauge network over Japan using available data observed by Japan Meteorological Agency (JMA), the River Bureau under Ministry of Land, Infrastructure, Transport and Tourism (RB-MLIT) and local governments (L-Gov). As a result of analysis of elevation, rain-gauge stations have been installed at a constant rate by each elevation class of the topography, and Japan has no rain-gauge stations over altitude 2500m. As a result of observation density by mesh analysis, approximately 70% of rain-gauge stations could observe rainfall data. In addition, we analyzed between DID and flood/drought disaster in recent years and observation density over Japan.

DOI： 10.2208/jscejhe.67.I_295

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Language：Japanese   Publishing type：Research paper (scientific journal)  

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

To clarify the properties of the thermal environment of a water-retentive artificial turf system (W-ATS), we estimated the hydrologic parameters of thermal conductivity, heat capacity, and surface albedo of the W-ATS and natural grass. We measured surface temperature and evaporation of the W-ATS and natural grass using a model experiment. <BR>As the results, the properties of the thermal environment of the W-ATS were as follows. Thermal conductivity of the W-ATS was lower than that of natural grass and it is difficult for the W-ATS to convey a radiant heat to the ground. Heat capacity of the W-ATS was lower than that of natural grass, and it contributed that surface temperature change of the W-ATS is larger. Therefore, surface temperature of the W-ATS was higher than that of natural grass in the daytime and lower at the nighttime. Albedo of the W-ATS was one fourth of that of natural grass and reflected shortwave radiation from the WATS surface was lower than that from natural grass surface. These results indicate that the WATS leads to the rise of soil temperature. Furthermore, it was found that evaporation of the W-ATS was one fourth of evapotranspiration of natural grass.

DOI： 10.3178/jjshwr.23.18

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Language：Japanese   Publishing type：Research paper (scientific journal)  

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

Fukuoka University constructed a football field using a new-type artificial turf with improved soil on May 2007 in order to mitigate urban heat-island phenomenon and urban flooding. To clarify hydrometeorological environment in the football field, we installed the hydro-meteorological observation system inside the football field. Furthermore, potential evaporation from the football field was measured using the model experiment.<BR>As a result of the hydro-meteorological observation, meteorological environment over the artificial turf was analogous with environment over natural grass. In the nighttime, air temperature over the artificial turf was about 5 degree Celsius lower than in urban area. Moreover, runoff ratio of the field was 12%-14.5% and a lag time between peaks of a flood and a maximum rainfall was 4hours. As a result of the evaporation model experiment, evaporation rate from our proposed artificial turf system was slowly and continuously during 10 days. The new-type football field contributes to the mitigation of urban heat environment and urban flooding.

DOI： 10.2208/prohe.52.265

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

We carry out the microclimate field observation collaborated closely with local residents in the downtown of Tokyo in order to study the effect of watering on urban climatic environment. Local residents sprinkled recycled water which was rainfall and/or bath water in summer. Then we measured air temperature, humidity, solar radiation, aerosol number, wind velocity and wind direction all the day. We could observe atmospheric phenomena before/after watering. The following conclusions were obtained: 1) Air temperature at almost all observation stations were started to decrease immediately after watering started. Area-averaged air temperature declined by 0.5 deg. C. After Watering, it took an average time of 60 minitues to relapse to the air temperature immediately before the sprinkling. 2) Surface temperature of roadway decreased from 50 deg. C to 40 deg. C compared between before and after Watering. Assuming the surface of roadway could be black body, long-wave radiation declined from 620 W/m^2 to 510 W/m^2 compared between before and after watering. Heat environment mitigation action by watering could be divided into &ldquo;fall of air temperature&rdquo; and &ldquo;restraint of radiation&rdquo;.

DOI： 10.2208/prohe.52.277

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

We have estimated natural runoff independent of human activities using a watershed hydrological model for the Chao Phraya River basin, Kingdom of Thailand. In order to assess the flood control and water supply capacities of two large scale reservoirs, the observed daily river discharge have been compared to the estimated values. We observed that the reservoirs' operation affected not only the increase of low flow but also the stabilization of river discharge. We estimated that the peak discharge at Hydrological Station C.2 (Nakhon Sawan city), which is the most important station for water related policies, would decrease by a maximum of 57.8% of maximum discharge and an average of 42.4 % of maximum discharge due to reservoir operations. Moreover, small and middle scale flooding was decreased by about 40 % and large scale flooding was decreased by about 35 % due to the development of the two large scale reservoirs.

DOI： 10.3178/jjshwr.20.145

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Other Link： https://jlc.jst.go.jp/DN/JALC/00298669941?from=CiNii

Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

To understand the long term change in river flow is basic information in order to estimate water resources in region and/or watershed. One of ways to obtained above mentioned information from river flow data is the flow-duration curve. It is too difficult to grasp the condition of the watershed using the flow-duration curve because the flow-duration curve depends on rainfall. <BR>In this paper, we propose a new flow-duration curve which does not depend on rainfall. This new flow-duration curve was estimated by runoff ratio using moving average runoff and rainfall. <BR>As a result of new flow-duration curve, the difference among three case study watershed's flow regime can be observed clearly. A new flow-duration curve, which we proposed, could clarify the watershed conditions like land use and/or soil characteristics using only historical river flow and rainfall data.

DOI： 10.2208/prohe.51.379

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

Human activities such as urbanization, reservoir development and deforestation affect on the watershed hydrological circulation. The purpose of this study is to clarify the impact of controlled landfill system on the watershed hydrological circulation. In this paper, the Seibu landfill system and the Zuibaiji River basin in Fukuoka prefecture was selected for this study. <BR>As a result, we observed that outflow rate of leachte treatment plant was fairly constant independent of precipitation variation. Moreover, we estimated the rain-runoff mechanism at Fukuoka Seibu (Nakata) landfill site. We suggest that the controlled landfill system is going to affect on the watershed hydrological circulation in the near future.

DOI： 10.3178/jjshwr.20.530

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Language：Japanese   Publishing type：Research paper (scientific journal)  

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

In order to assess the effect of human activities, such as land use change and large-scale reservoir development on river flow regime, we have developed a hydrological circulation model using MIKE11 for the Chao Phraya River basin. We have tested the effectiveness of this model. River discharge and water level during 1956-1962 when large-scale development had not been carried out in the Chao Phraya River basin yet were simulated using MIKE11.This model was able to estimate the river discharge and water level with a high degree of accuracy. Comparisons with the actual measurements have proved the validity of our model.

DOI： 10.3178/jjshwr.19.212

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Other Link： https://jlc.jst.go.jp/DN/JALC/00278525540?from=CiNii

Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

In order to the mitigation effect on urban heated environment of urban park, the microclimate observations have been carried out in an urban park and its surrounding in Tokyo since 1998. We have installed the 17m height observation tower with the sensors to measure air temperature and humidity at each 2m within the forest during 1st-30th July 2005. And also 19 measurement systems for air temperature and humidity were installed inside and outside the forest. As a result, the existence of clearly high- temperature and humidity layers were caught in canopy layer during the daytime. This means the exchanges of latent and sensible heat were very active in the canopy layer. In night, specific humidity near the ground was higher than that of upper layer because of continued evaporation from the ground surface. Moreover, when the flux of solar radiation was less than 300W/m² (e.g. cloudy day and nighttime), air temperature inside the forest was lower than outside the forest; maximum difference was 5 degrees Celsius. However, there was stark difference air temperature between inside and outside the forest during the sunshine daytime. We can not clearly identify the mitigation effect on urban heated environment of urban park in this field observation.

DOI： 10.2208/prohe.50.505

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Language：Japanese   Publishing type：Research paper (scientific journal)  

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Publishing type：Research paper (scientific journal)  

To grasp the temporal and spatial distribution characteristics of the pan evaporation amount in the Chao Phraya River basin, in the Kingdom of Thailand, the writers performed an analysis over a period of 19 years, from 1982 to 2000, where data related to the target area were available. Geographic, seasonal, and annual changes were studied. As a result of performing trend tests on annual changes, negative trends were found in 24 out of 27 observation stations. Furthermore, nine of those locations had a significant negative trend. As a result of performing tests of concurrent rainfall over the same period, although there were positive trends in 8 locations and negative trends in 19 locations, no significant trend - either positive or negative - was obtained. This result does not match a finding that precipitation increase decreases pan evaporation in the United States, a finding that can be derived from the complementary relationship. Journal of Hydrologic Engineering © ASCE.

DOI： 10.1061/(ASCE)1084-0699(2005)10:3(205)

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

The social experiment was carried out for the purpose of the mitigation of the heat island effect by watering on August 18th to 25th. The microclimate observation has been carried out at watering area in Eastern Tokyo. As the results, the effect of the watering on the thermal environment in urban area was evaluated as decreasing effect on temperature. The following results were obtained; 1) The temperature variation in the daytime is included to be different every site because of the dispersion of surface temperature. 2) The air temperature in the experiment area is from 2 to 9 [degree] higher than temperature in thermometer shelter by the effect of long radiation. 3) The temperature decrease instantaneously when watering starts. 4) The temperature decreases 0.66 [degree] on average, 1.93 [degree] on maximum after the watering. 5) Total amount of decreasing temperature is decreased linearly by the distance from the point of watering.

DOI： 10.2208/prohe.49.367

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

The goal of our study is to clarify the effect of the human activities on water resources and water circulation. The Chao Phraya River basin was selected for this study. The Chao Phraya River basin, the largest basin in Kingdom of Thailand is located in central and northern part of Thailand. This basin has two large-scale dams named Bhumibol Dam across the Ping River and Sirikit Dam across the Nan Riven This large storage dams are beneficial to the country for generating electricity and discharging water for the irrigation project areas and flood mitigation on both banks of the Ping, Nan and the Chao Phraya rivers.<BR>This paper has evaluated the water usage and flood control facilities of Bhumibol Dam. As the results of comparing the annual change of monthly runoff before and after dam construction, the minimum runoff increased drastically and the maximum runoff decreased.<BR>As the results of numerical analysis, it is clarified the water usage has become stable and the high water has decreased by the operation of Bhumibol Dam.

DOI： 10.2208/prohe.49.457

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Language：Japanese   Publishing type：Research paper (scientific journal)  

The second largest flood in 2002 occurred in the Chao Phraya River basin, Kingdom of Thailand. The field survey was carried out in the middle and lower part of the Chao Phraya River basin two weeks after the peak of the flood terminated. The result indicated that middle basin, especially Ang Thong, Ayutthaya and Sing Buri cities had suffered a heavy damage. In the meantime, there was little serious damage from the inundation by river water in Bangkok city that is located in the lower basin area. The following two factors are mentioned as the reason; (1) In Bangkok, the flood discharge had been reduced by the time it reached the lower basin area because of the overtopping in the middle basin. (2) The flood discharge has been degreasing in the downstream of the Chao Phraya River basin year by year since the Bhumibol and the Sirikit dams were constructed in the upper basin. In addition, the evaluation of the provability was carried out on the flood in 2002 using the generalization extreme value distribution. The flood was estimated under the 10-year return period discharge and it turned out the flood with the high possibility of occurrence.

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Other Link： http://dl.ndl.go.jp/info:ndljp/pid/10751837

Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

This paper aims to find out changes with temporal and spatial distribution in pan-evaporation in the Chao Phraya River in Kingdom of Thailand. The monthly pan-evaporation data during the 1982-2000 period was obtained from all-available observatories and analyzed. The following results were obtained: (1) the pan-evaporation value is the highest in the lower Chao Phraya River basin which is closer to the ocean, and its value is gradually degreases in upper basin; (2) the March-May period sees much evaporation than other months of the year; (3) and trend tests show significant decrease in pan-evaporation in 24 out of 27 observatories.<br>The trend tests on annual precipitation over the Chao Phraya River Basin in the corresponding period show that no significant decreasing or increasing trends at any stations. This result does not match a finding that precipitation increase decreases pan-evaporation in the U.S.A. (Lawrimore and Peterson; 2000), which finding can be derived from the complementary relationship (Brutsaert and Parlange; 1998). The reason for decrease in pan-evaporation without any precipitation change could be degrease in the solar radiation, which cannot be confirmed because of lack of data.

DOI： 10.3178/jjshwr.17.468

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

The large-scale social experiment, which many citizens including media representative participated for evaluating the effects of the watering on the &ldquo;Heat Island Effect&rdquo;, was carried out in Tokyo Metropolitan in Aug. 25 2003. About 14000l. water were sprinkled for about 20 minutes from noon. Air temperature and humidity were measured by moving observation system and fixed observation system at watering area in Eastern Tokyo. After the watering, the air temperature difference between outside and inside of watering area increases, and its difference was about 0.5&deg;C. Temperature of watering area is lower than the temperature of outside area of watering after the watering. The effect of the watering was verified using the numerical simulation based on MM5. As a result of this analysis, air temperature degreased 2-2.5&deg;C in watering area after the watering.

DOI： 10.2208/prohe.48.193

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

The purpose of this paper is to evaluate the effect of the human activities on water resourcesand hydrological cycle. The Chao Phraya River basin was selected for this study. The Chao Phraya River basin, the largest basin in Kingdom of Thailand is located in central and northern part of Thailand. This basin has two large-scale dams named Bhumibol Dam across the Ping River and Sirikit Dam across the Nan River. This large storage dams are beneficial to the country for generatingelectricity and discharging water for the irrigation project areas and flood mitigation on both banks of the Ping, Nan and the Chao Phraya rivers.<BR>There is no the long-term increase and decrease tendency of the precipitation. As the results of comparing the annual change of monthly runoff before and after dam construction, the minimum runoff increased and the maximum runoff degreased.<BR>As the results of spectrum analysis using FFT, after the Bhumibol dam was constructed, the daily runoff in Nakhon Sawan had period characteristics in 3.5days and 7days and the released water from the Bhumibol dam had period characteristics in 2.5days, 3.5 days and 7days. Dam operation effected on the hydrological cycle considerably.

DOI： 10.2208/prohe.48.481

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Publisher：Japan Society of Civil Engineers  

Local scientists and engineers in Thailand have recognized and pointed out a decreasing trend in discharge in the Chao Phraya river in recent years. However, no solid data or analysis to show a decline has been reported. This study is to find trends in river discharge data and to analyze significant causes of the trend. The following results were obtained:(1) As a result of examining discharge at 10 gauging stations in the Chao Phraya river basin, the significant decline of the annual discharge is found at 8 stations out of the ten;(2) 17 out of 18 sub-basins of the Chao Phraya river basin have no tendency in annual rainfall change, but the only one sub-basin in the upper Yom river basin has tendency of declining rainfall according to the Kendall rank test at 95% significance level;(3) and it is considered that major cause of the discharge decline is a change of the land use to cropland such as the orchard from paddy field rather than rainfall.

DOI： 10.2208/prohe.47.205

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Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

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Publisher：Japan Society of Civil Engineers  

The purpose of this study is to clarify the role of forest in urban area from a viewpoint of urban environment by observing the leaf temperature and micrometeorological factors, such as air temperature, wind speed, humidity, solar radiation, soil heat, and CO₂ concentration. In the midsummer of August 2000, the micrometeorological observation was carried out at Koishikawa Korakuen Gardens (in Bunkyo-ku Tokyo, Japan) for a week. The following results were obtained: 1) In the daytime, the leaf temperature rapidly lowered, when some critical conditions were exceeded. In the nighttime, the air and leaf temperature were almost the same. 2) When the flux of solar radiation increased above about 400W/m², the leaf temperature lowered linearly with it. 3) Within VPD (vapor pressure deficit) became higher than 4hPa, the leaf temperature rapidly lowered further than the air temperature. 4) Simultaneously with this, the carbon dioxide concentration began to lower.

DOI： 10.2208/prohe.45.265

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Language：Japanese   Publisher：土木学会  

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J-GLOBAL

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Language：Japanese   Publisher：土木学会  

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Language：Japanese  

DOI： 10.3178/jjshwr.30.237

J-GLOBAL

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J-GLOBAL

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

&amp;nbsp;The purpose of this study is to compare the elementary composition of the beach sand in the KUROBE river with bowling core sample in UNADUKI &amp;nbsp;lake observed H24,H25, and H26 using handheld X-ray fluoresence.As a result, recovery of the beach sand&amp;nbsp;wad the influence of cooperation sand elimination in the UNADUKI dam.The relation of the beach sand and &amp;nbsp;bowling core sample is gained very similar tendency.

DOI： 10.11520/jshwr.29.0_89

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Language：Japanese   Publisher：電力土木技術協会  

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Language：Japanese  

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Language：Japanese   Publisher：土木学会  

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DOI： 10.2208/jscejer.71.I_37

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Language：Japanese   Publisher：土木学会  

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Language：Japanese   Publisher：土木学会  

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Language：Japanese   Publisher：土木学会  

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Language：Japanese   Publisher：土木学会  

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

To propose a new reservoir operation for large scale dam reservoir in&nbsp;<br>Thailand, the Bhumibol and Sirikit dam reservoirs in the Chaophraya River&nbsp;<br>basin were selected for this study.

DOI： 10.11520/jshwr.26.0.78.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

the complex two layerd flows happen in the estuary. The upper and lower&nbsp;reaches in HIGASHI UCHIKAWA RIVER connect with the sea. So, the speed of flow is small and the water pollution happened. To clarify the complex flow, the sea - Channel - Closed water body combination model based on the closed conduit flow was developed, and study how to increase the speed of flow.&nbsp;

DOI： 10.11520/jshwr.26.0.44.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

This paper reports that characteristics of seasonal change in discharge and water quality of artesian well in the Kurobe alluvial fan.

DOI： 10.11520/jshwr.25.0.190.0

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Language：Japanese   Publisher：GEOCHEMICAL SOCIETY OF JAPAN  

DOI： 10.14862/geochemproc.59.0.305.0

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Language：Japanese   Publisher：水文・水資源学会  

DOI： 10.11520/jshwr.25.0.58.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

This study shows&nbsp;results of further discussions&nbsp;based on the analysed data of investigation and observations in June, August and September in 2011in the Sanriku area attacked by Tsunami on March 11 in 2011.&nbsp;&nbsp;We measured&nbsp;chrolide ion concentaration in a few wells and analysed isotope of groundwater.&nbsp; As a result, we pointed out&nbsp;that &nbsp;unconfined groundwater for water supply was pollueted by sea water of Tsunami..

DOI： 10.11520/jshwr.25.0.200.0

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J-GLOBAL

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J-GLOBAL

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.24.0.91.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.24.0.36.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.24.0.139.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.24.0.105.0

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Language：Japanese  

J-GLOBAL

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Language：Japanese   Publisher：Toyama Prefectural University  

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.23.0.135.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.23.0.34.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.23.0.139.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.22.0.122.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.22.0.33.0

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Language：Japanese   Publisher：体育施設出版  

CiNii Books

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.21.0.107.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.21.0.60.0

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Language：Japanese   Publisher：水文・水資源学会  

CiNii Books

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.20.0.130.0

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Language：Japanese   Publisher：日本下水道協会  

CiNii Books

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.20.0.55.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.20.0.5.0

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Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.19.0.7.0

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Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

We will open the PUB research batabase on our website. The scientific plan of PUB is to reduce the reduction in predictive uncertainty. It is very important to grasp the the uncertainty of hydrologic data in order to predict and estimate the discharge. This paper is discussed about the data quality.

DOI： 10.11520/jshwr.18.0.20.0

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Language：Japanese   Publisher：水文・水資源学会  

CiNii Books

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Language：Japanese   Publisher：水文・水資源学会  

CiNii Books

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Language：Japanese   Publisher：水文・水資源学会  

DOI： 10.11520/jshwr.17.0.78.0

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Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.17.0.216.0

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Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.16.0.194.0

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Language：Japanese   Publisher：水文・水資源学会  

DOI： 10.11520/jshwr.16.0.64.0

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Language：Japanese   Publisher：水文・水資源学会  

DOI： 10.11520/jshwr.16.0.196.0

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Language：Japanese   Publisher：水文・水資源学会  

DOI： 10.11520/jshwr.15.0.186.0

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