Hydrological regions in monsoon Asia

Abstract

Abstract:Monsoon Asia is characterized by its diversity of natural and social environments. These environments range from humid tropics to arid regions and there exist associated various hydrological phenomena. This paper attempts to characterize the hydrological regions of monsoon Asia based on the water budget calculated using grid-based global datasets. A map of hydrological regions is created by ranking the value of water surplus and deficit. A humid zone with large water surplus extending from Southeast Asia to the Japanese archipelago, rapid transition from humid to arid environments in eastern China, and an arid region surrounded by a humid region in continental Southeast Asia are the most remarkable features in monsoon Asia. The map reveals that an essential characteristic of monsoon Asia is the proximity of the arid and humid environments. Many water problems and water management practices in a region can be easily understood by plotting them on a map. The boundaries of several large river basins are superimposed on the map, and examined for the water budget and flow regimes. The results are found to explain the regional characteristics of the seasonal runoff regimes satisfactorily. The importance of using a spatial framework for the comparative hydrological study in Monsoon Asia is highlighted.

A comparative overview of weathering intensity and HCO3− flux in the world's major rivers with emphasis on the Changjiang, Huanghe, Zhujiang (Pearl) and Mississippi Rivers

“…The total area of the drainage basin is 1.81 Â10 6 km 2 , or nearly 20% of the total area of China, and it alone sustains a population of 420 million. In the Changjiang basin, annual precipitation (1253 mm yr À1 ) greatly exceeds the evaporation loss (801 mm yr À1 ) (Kondoh et al, 2004). Because of the weathering of the abundant carbonate rocks in the drainage basin, Ca 2+ ($1.5 mM), Mg 2+ ($0.6 mM) and HCO 3 À ($1.9 mM) concentrations are rather high in the river water, while pH is slightly basic ($7.9).…”

Simulating monthly streamflow for the Upper Changjiang, China, under climatic change scenarios / Simulation du débit mensuel du Haut Changjiang, en Chine, sous des scénarios de changement climatique

“…Most parts of Upper Changjiang basin lie in an area of water surplus, particularly in the north (Kondoh et al, 2004). The exception is its headwater zone on the Tibetan Plateau which is an area of water deficit.…”

Dampak Perubahan Penutupan Lahan Terhadap Evapotranspirasi Aktual

“…The result of monthly 0 E analysis has been used together with monthly precipitation and soil water holding capacity ( c W ) on the next step to calculate a E as shown in Figure 2 and the detail could be referred to Thornthwaite and Mather (1957) and Kondoh et al (2004).…”