陸面解析による灌漑取水とアラル海の消長に関する応答解析 : アラル海流域の持続可能性向上へ向けて

Abstract

深刻な水資源問題が発生している中央アジアでは, 今後の持続可能な開発へ向けた科学的根拠として, 流域の水資源・需要量や, 各種の対策の効果を推定する手法が必要である. 本研究では, 陸面過程モデルSiBUCを中心としてアラル海縮小を組み込んだ水循環モデルを用い, 灌漑効率や灌漑手法, 灌漑面積等を改善する仮想的な対策を設定し, これらの改善がアラル海水量に与える効果について定量的に推定した. その結果, 過去の灌漑手法が実際より改善されていた場合に, 現在より多くの水がアラル海へ流入し, 持続可能な社会に向けた対策として効果があることが分かった.

As a result of huge-scale irrigation project in the Soviet age, serious water scarcity has occurred in the Aral Sea Basin. Millions people are suffering especially in the downward area and the Aral Sea has shrunk to 10% from 1960's level. Sustainable irrigation project is required and this has to be based on scientific information about feasible water resource and water demand in irrigated farm. These information are necessary as basic and scientific information for sustainable development. In this study, water circulation model has been developed by land surface model with Aral Sea shrinking scheme and historical water balance in the Aral Sea Basin was reproduced. And with the model, scenalio analysis of changing irrigation method was examined. The scenalio was about improving irrigation efficiency and decreasing irrigated area. As a result, positive effects were cleared in all scenalios and the speed of the Aral Sea shrinking was more moderate than real situation.