The effect of land cover change on river flow and inundation is one of the most important issues in river basin management. The Jobaru River is located in Saga Prefecture. From 1948 to 2005, due to high demand in residential areas, the Jobaru River basin had been affected by changes in land cover. Barren areas tended to turn into forest in the mountainous sub-basin, while in the plain sub-basin, paddy fields turned into urban or built-up land. If these changes continue, it is feared that they will affect the flow of the Jobaru River. Therefore, in this book, we will look at the effect of land cover changes on the hydrological processes in the Jobaru River basin. In doing so, we hope to utilize its results as a step for integrated river basin management planning.
All this time, handling of the Jobaru River environment has been more focused on the mountainous sub-basin. On the other hand, there was less attention to the plain sub-basin. The changes of land cover from agricultural land to urban areas in the plain sub-basin had significant effects on increasing the discharge in the downstream of the Jobaru River basin. Still, it does not influence the discharge in the Jobaru River outlet. To manage the flood in the Jobaru River, we should consider the land cover changes not only in the mountainous sub-basin but also in the plain sub-basin, and the discharge should be considered not only in the river but also in the land area. This result can be applied to river basin management.
This book provides a reference about how the effect of land cover changes can be an important part of the integrated Jobaru River basin management. This will be a useful step for future integrated river basin management, which is expected to be used as the foundation for the sustainable development of the Jobaru River basin in the future.
