Keyword: Water Balance Model, Discharge Map, Water Resource Distribution Map
Abstract
In 21th century, food problem may become much more serious due to the
increasing world population. The number of nations importing grains continues to grow
steadily. Since water resource is done of the most important limiting factor, quantitative
analysis of available water resource is necessary to evaluate the potential growth of
agricultural productivity that is enhanced by irrigation system. A hydrological model based
on "Water Balance Model" is proposed in this paper to simulate monthly water resource
distribution at global scale using Remote Sensing data and GIS. Water Resource Distribution
Map is being generated by means of hydrological model. The result has been verified using
runoff data of great rivers of Asia. Global map of water resource may help in planning of
irrigation system in order to enhance the agricultural productivity as well as food demand of
increasing world population.
1.Background and Purpose
Demand for water is growing rapidly as populations and industrial activities expand
and irrigated agriculture continues to increase. World Resources Institute reports that
from 1940 to 1990, withdrawals of freshwater from rivers, lakes, underground aquifers
increased. Many current patterns of water withdrawals are clearly unsustainable, such
as pumping from subsoil aquifers at rates far greater than they are recharged.
Freshwater habitats are threatened by water shortages, which are already critical in
some regions. And it is posing obstacles to sustainable development of human society
itself.
The future availability of water for human use depends on how water resources are
managed. Especially, in water-shortage regions, pressures on management of water
resources will become more important. According to estimate by World Resources
Institute, 1 billion to 2.4 billion people (13 to 20 percent of the projected world
population) will live in water-scarce countries by 2050. Africa and some countries in the
western Asia appear particularly vulnerable in the population explosion. Therefore,
water resources map at a global scale is strongly required to support the improvement
of water use efficiency, avoiding wasteful water use, preserving supplies and planning
irrigation system.
In this research, firstly the authors produced “Discharge Map” using a hydrological
model based on "Water Balance Model" and “DDM(Drainage Direction Matrix)”. Next,
authors proposed a model for estimating water resources on the basis of “Discharge
Map”, then, examined the reliability of the model and finally produced “Water Resource
Distribution Map”. Figure 2-1 shows flowchart of this research.
Figure 2-1 Flowchart of This Research
2.Data set
Table 2-1 shows data sets used in this research.
Table2-1 Data Set in this research
| Variable
| Content description
| Source
| Form
| Resolution
|
| Annual Water balance
| water balance (mm/y)
| Chiba University
| raster
| 30 minutes
|
| GTOPO30
| DEM on global scale (m)
| U.S.Geological SurveyEROS Data Center
| raster
| 30 seconds
|
| DCW (Digital Chart of World)
| Drainage Network
| ESRI Incorporation Global Coverage GIS Database
| vector
| -
|
