THE PRODUCTIVE AREAS AND TRANSPORTING PROCESS OF WASH LOAD IN MOUNTAINOUS DRAINAGE BASINS

Abstract

There are the following important factors in treating the problems of wash load inmountainous drainage basins. First, where are the production areas of wash load? Secondly, what is the mechanics of erosion in the area under consideration? Thirdly, How can weevaluate the distribution of discharge all over drainage basin? This paper concerns the firstsubject of the three.The range of particle sizes of wash load is discussed first with theoretical backgroundsand many field studies. We propose it is enough for us to take the finer particles intoconsideration than 100μm diameter in the study of wash load. It is clarified from variousfield investigations that the wash load is mainly produced in stream channels and on bareslopes. The eroding processes at the production areas of wash load are also discussed onthe basis of data.There are the following important factors in treating the problems of wash load inmountainous drainage basins. First, where are the production areas of wash load? Secondly,what is the mechanics of erosion in the area under consideration? Thirdly, How can weevaluate the distribution of discharge all over drainage basin? This paper concerns the firstsubject of the three.The range of particle sizes of wash load is discussed first with theoretical backgroundsand many field studies. We propose it is enough for us to take the finer particles intoconsideration than 100μm diameter in the study of wash load. It is clarified from variousfield investigations that the wash load is mainly produced in stream channels and on bareslopes. The eroding processes at the production areas of wash load are also discussed onthe basis of data