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Recently, some localized heavy rainfall events which are especially affected by global climate change causing urban flooding has brought a lot of disaster. On the other hand, urban river water pollution derived from non-point source distributred with urban surface has been becoming relatively important after point source pollutant reduction. In this study, effectiveness of the real time control (RTC) of urban storage system for both purpose of flood prevention and pollutant reduction is estimated by continuous simulation with prediction of the latest RADAR precipitation system..

In Kyoto Basin, high quality and abundant groundwater has been used for drinks, industry, or agriculture. However, in 20th century, there were some problems like the land subsidence because of groundwater exploitation in rapid economic growth. On the other hand, circumstances surrounding groundwater are changing. For example, extreme meteorological phenomenon such as the local heavy rain or the abnormal drought causes more frequent disaster. There are many researches about climate change impact on river flow, but there are a few about impact on the groundwater environment. Therefore, in this study, in order to use groundwater sustainably, we assess global climate change impact on groundwater environment. We use two dimensional saturated groundwater flow model, it is generally used, and we assess climate change impact on groundwater environment quantitatively by ensemble climate experiment.

In recent years, generation of urban flooding has become a problem. On the other hand, water pollution of urban river due to the influx of pollutants from non-point source also has become a problem. Therefore, in this study, to make effective use the big tunnel rainwater storage facility, named Donryu" in Nishi -hadukashi river basin, in both purpose of preventing flood and pollution and to propose control strategy, the optimal application strategy of RADAR forecasting information is estimated by a probabilistic analysis of flooding risk derived from the error of predicted rainfall."

In order to evaluate groundwater environment for appropriate and sustainable use, impact assessment should be carried out with considering global climate change in future by using groundwater flow and water quality model. In this study, generally used type of two dimensional saturated groundwater flow model and advection-dispersion equation for Total Nitrogen (T-N) are used. Precipitation data is supplied from GCM calculation results (MRI-AGCM3.2s), where single mesh can almost cover study area because spatial resolution of this data is 20km. In order to obtain probabilistic estimation from simulation results calculated by a lot of precipitation information, rainfall data surrounding meshes of target area are applied. A risk of groundwater drawdown and water quality deterioration is evaluated with time and space domain by using multiple calculation results. These results are analyzed by using of probabilistic distribution function (PDF).

京都盆地水系における将来的な水資源の利用可能性や水環境の保全対策を検討・実施するためには、地下水利用の現状を把握するとともに, 水質汚染状態を管理する必要がある。地下水は一度汚染されると短期間での汚染改善は困難であり, 汚染状態の継続は長期間に及ぶため, 水資源の安全な利用の観点からも地下水質の継続的な監視が求められる。さらに, 地震等災害時の緊急用水としての地下水利用可能性を検討するためには, 時空間的な水位・水質分布特性の解析が重要となる。そこで, 本研究では, 京都盆地水系における平面二次元および準三次元の地下水流動・水質解析を行い、汚染源からの物質伝播の時空間的な影響範囲の予測について検討した。, It is important to investigate and analyze the groundwater Quality conservation and utilization of the water resources. Especially, it refers to water resource management for the future and emergency water supply. In former study, analysis of groundwater quality in Kyoto basin indicated water quality of wells located around the basin belongs to different water quality type than surface water. It requires another pollutant sources than surface water recharge for groundwater quality management. So, in this study the quasi three-dimensional model is applied for analysis of groundwater quality in Kyoto Basin.

京都盆地水系の地下水は古来より飲料用や産業用に利用され，その良好な水質は多くの名水・名井として保全・活用されてきた。高度経済成長期の過剰な揚水による盆地南部域での地盤沈下は，その後の規制により沈静化してきたが，現在も湧水の消失や散布肥料・工場排水等による水質汚染などの問題がみられる。本研究では，京都盆地の地下水動態を明らかにし，今後の地下水利用の適正化を図ることで，持続可能な水資源としての利用を進めるために，表流水と地下水間の水・物質挙動の解析を行った。まず京都盆地における地下水の既存の水質観測データ，および独自の連続観測のデータからヘキサダイアグラムによる水質分類を行い，表流水の地下水への影響を評価した。次に連続観測のデータを用いて数値シミュレーションモデル計算結果のフィ?ドバックを行い，水収支と汚染物質動態の両面からモデルの改良を試みた。, The groundwater in Kyoto basin has been utilized for the domestic and industrial use, because of stable water temperature and good water quality. The ground subsidence in the southern part of the Kyoto basin by an excessive pumping during the high economic growth period has been made quiet by the legal restriction afterwards, but there remain some problems such as spring water depletion and water pollution in present. In this study, water budget and pollutant balance between surface water and groundwater in Kyoto basin are observed and analyzed for sustainable utilization of groundwater resources. The groundwater flow is simulated by the two-dimensional saturation groundwater model, and ground water quality is also simulated by the advection and diffusion water quality model. These numerical simulation models are improved by feedback loop between each model output for the concordance of water budget and pollutant balance.

新疆ウイグル自治区のほとんどは乾燥地域であり，耕地開発・工業開発および気候変動等の影響で河川表流水の減少，地下水位低下などにより生活用水の確保難や水質悪化，農地の荒廃等の深刻な問題が発生している。そのため，将来的な水資源の確保および水環境の保全に対する有効な対策を検討する必要があるが，タリム河流域における水・物質循環構造に関しては物理的な現象解明はほとんど進んでいない。そこで，本研究では飽和平面二次元地下水流動モデルを用いて，タリム河流域全体の地下水水位および流動特性の解析をおこない，流域全体における水資源利用に伴う地下水流動状況の変化について検討した。, Tarim River, which is one of the longest inland rivers in China, mainly supplies water resources for the human society and the agricultural activity in Teklimakan Desert. Water resources and water environment in Tarim river basin are fundamentally poor because of arid area condition. Furthermore increasing of irrigation water and pollutant load inflow derived from national development projects in this area brings much damage on the Tarim basin environment. Especially, river surface flow in downstream area was intermittently dried up and groundwater level has been gradually dropped. Groundwater flow analysis in Tarim river basin was carried out by the numerical model and water resources conservation measures were discussed.

近年，都市部での局地的集中豪雨による内水浸水等の被害が顕在化しており，本研究で対象とする西羽束師川流域でも治水対策の一貫として大型地下トンネル貯留施設が建設中である。一方，流域内の市街化が進みさまざまな負荷源から流出する汚濁物質により河川水質は汚染されているが，非特定負荷源からの汚濁負荷に関する実態調査が皆無であり，削減対策の検討のための基礎的情報が不足している。そこで，本研究では雨水流出・汚濁負荷流出の実態調査とその流出解析およびモデル化を行った。その結果，対象流域内の雨水流出および汚濁負荷流出機構の特性を明らかにするとともに，今後の調査の要点，負荷削減策についての検討を行った。, In this study, availability analysis is focused to use the flood control system for pollutant reduction derived from non-point sources. Big tunnel stormwater storage system named "Donryu" is under construction in Nishihadukashi river basin for flood prevention. This paper shows that basic investigations of stormwater and pollutant runoff in this basin continuously carried out from 2004 to clarify the runoff characteristics and effectiveness of pollutant reduction measures. Water level and water quality are automatically monitored by electric sensors. Continuous stormwater samplings were carried out in several rainfall events. Stormwater and pollutant runoff analysis by numerical models had good performance to simulate observed data. Some water quality characteristics are defined by the observation and simulation. Finally, pollutant reduction measures in near future are discussed.

将来的な水資源確保と水環境保全のために，河川流域における水文循環を水系の一環として捉え，経年的な変化を知り将来予測を行うことは重要である。そこで，本研究では京都市内を流れる鴨川水系を対象として，河川の流量および水質，河床中の地中水の水位および水質観測を行い，これに基づいて河川と地中水との間の水および物質挙動の解明を目的とした解析を行った。その結果，対象領域においては河川流量に対して地下水からの流量影響が10～20％程度存在するとともに，湧水における全窒素濃度は河川水と比較すると3倍程度であることが明らかとなった。そこで河川流出と地下水流動を結合した統合流出モデルを構築し，観測値を基に計算パラメータを決定した。最後に統合流出モデルに物質循環モデルを導入して対象領域での水・物質循環構造について考察を行った。, The continuous runoff analysis through dry and wet condition is demanded in order to clarify water budget and material balance in large area. The water budget model between river water and groundwater based on the continuous observation of river water quality and quantity, and two-dimensional groundwater analysis was carried out. The result shows that the amount of groundwater exchanged with river water in the observation area was 10 to 20％ of that of river water. It indicates that interaction between river water and groundwater is significant on the water budget and material balance in river basin.

新疆ウイグル自治区は典型的な乾燥地域であり，水資源が乏しく，生態環境も脆弱である。中国中央政府の西部大開発による経済発展と移民人口の爆発的な増加に伴い，この地域の水資源環境は急速に悪化しており，水資源賦損量の確保と水質汚染防止は緊急の課題となっている。本論文では，新疆ウイグル自治区南部のタクラマカン砂漠の北を流れるタリム河流域を対象として，これまでに行われてきた複数の調査資料を収集・整理し，タリム河の水量・水質環境の現況を分析するとともに，今後の水利用増大に伴う水資源環境の変化に対応した対策の検討をおこなう。, Water resources and water environment are poor, because Xin Jiang area is almost covered by arid area. National project has been bringing economic development and population increasing in this area. Tarim River, which is one of the longest inland rivers in China, mainly supplies water resources for human society and agricultural activity. River water environment has been damaged by increasing of irrigation water and pollutant load inflow River water quality management policies should be quickly established for water resources conservation in near future

近年，下水道の整備などにより家庭や工場といった発生源が特定できる特定汚染源（Point Source）からの汚濁負荷流出が削減され，晴天時の公共用水域の水質改善が図られてきた。しかし，地表面等に堆積した汚濁負荷流出に伴い流出する非特定汚染源（Non-Point Sources）からの汚濁負荷流出については十分な対策がとられていない。特に，都市活動などによって晴天時に都市表面に堆積した大気降下物が，降雨に伴い河川へと流出する過程について解明することは，今後の河川水質を評価するうえで重要である。本研究では，晴天時において都市表面に堆積する大気降下物に着目し，その堆積量に影響を与える要因について考察を行った。まず，対象流域とした京都市内における自動車交通量データや大気汚染データを収集し，その傾向や特性について分析した。また，京都市内において大気降下物堆積量についての観測を行い，その分析結果により，自動車交通量や気象条件などが大気降下物堆積量に与える影響などについて考察を行った。, Dry depositions are important to estimate the impact of storm water runoff to urban water quality. The investigation and analysis of dry depositions in urban area was carried out in this study Results showed that dry depositions weight are more related to urban mobile transportation and air pollution than dry weather duration. Combination of air pollution advection and diffusion model and pollutant deposition model were modified for accurate estimation of dry depositions.