Comparison of gridded precipitation datasets for rainfall-runoff and inundation modeling in the Mekong River Basin.

Precipitation, as a primary hydrological variable in the water cycle plays an important role in hydrological modeling. The reliability of hydrological modeling is highly related to the quality of precipitation data. Accurate long-term gauged precipitation in the Mekong River Basin, however, is limited. Therefore, the main objective of this study is to assess the performances of various gridded precipitation datasets in rainfall-runoff and flood-inundation modeling of the whole basin. Firstly, the performance of the Rainfall-Runoff-Inundation (RRI) model in this basin was evaluated using the gauged rainfall. The calibration (2000-2003) and validation (2004-2007) results indicated that the RRI model had acceptable performance in the Mekong River Basin. In addition, five gridded precipitation datasets including APHRODITE, GPCC, PERSIANN-CDR, GSMaP (RNL), and TRMM (3B42V7) from 2000 to 2007 were applied as the input to the calibrated model. The results of the simulated river discharge indicated that TRMM, GPCC, and APHRODITE performed better than other datasets. The statistical index of the annual maximum inundated area indicated similar conclusions. Thus, APHRODITE, TRMM, and GPCC precipitation datasets were considered suitable for rainfall-runoff and flood inundation modeling in the Mekong River Basin. This study provides useful guidance for the application of gridded precipitation in hydrological modeling in the Mekong River basin.

The importance of mangrove forest in tsunami disaster mitigation.

Tsunamis and storm surges have killed more than one million people and some three billion people currently live with a high risk of these disasters, which are becoming more frequent and devastating worldwide. Effective mitigation of such disasters is possible via healthy coastal forests, which can reduce the energy of tsunamis. In recent years, these natural barriers have declined due to adverse human and natural activities. In the past 20 years, the world has lost almost 50 per cent of its mangrove forests, making them one of the most endangered landscapes. It is essential to recover them and to use them as a shield against a tsunami and as a resource to secure optimal socio-economic, ecological and environmental benefits. This paper examines the emerging scenario facing mangrove forests, discusses protection from tsunamis, and proposes a way to improve the current situation. We hope that practical tips will help communities and agencies to work collectively to achieve a common goal.