@article{oai:soar-ir.repo.nii.ac.jp:00011113, author = {清水, 邦夫}, journal = {信州大学農学部紀要}, month = {Sep}, note = {1) To make use of electric dam, to study on the run off, is more convenient, correct and uncost method than other methods. Because at electric dam we can easily get datas of long period of discharge and precipitation, if that dam was built long ago. 2) If the area is broad and have high mountains, that area have variable precipitations at the same time in oneself. So we must correct the precipitations to the mean precipitation of the area. At Miura dam of the Kiso river I use 1.2 to correct the precipitation at that dam to the mean precipitation of the area. At 3 gages of the Krobe river and at Minochi dam of the Sai river I use 1.5, 1.7, 1.8 and 1.5. 3) At Miura dam year rate of run off is 85％, at 3 gage of the Krobe are 73％, 67％ and 68％, and at Minochi dam is 86％. Monthly rate of run off in snow melt season is higher than monthly rates in other season. At these rivers monthly rate in snow melt season is higher than 100％. Especially at Krobe river the monthly rate in snow melt season is as tentimes large as the monthly rate in snow season. In discharge of 100 km area, the highest discharge is smaller at the same condition, if total area is larger, and dry discharge is higher. Because in broad area a part of precipitation makes sauce of water. If in discharge data daily discharge unit uses unit of ㎥/sec, we are convenient to Use K＝60x60x24/A(A＝area ㎥) 4) The relation of daily intesity of precipitation to daily rate of run off is,at Miura dam, (x＝daily intensity of precipitation y=daily rate of run off) in snow season y＝a/x＋b in snow melt season and nomal season y＝a/x+becx+d. (a. b. c. d. e ＝ constant) 5) In flood time, if area is larger, houre between peak of precipitaion and peak of flood is longer. Example, the houre between peak of precipitation and peak of flood at Miura is 0～1 houre but the houre at Minochi is 11 houres. In snow melt season, flood of larger rate of run off causes some times. 6) Statistic distribution of daily discharge (except flood daily discharge) is poisson distribution or logarithmic nomal distribution. 7) At some area we experience large erosion of earth, and chemical mateirals with run off of water. Example, at Minochi dam earth of 2,311,906㎥ was accumulated for 11 years. 8) I get next determination by study in small text area. a) The earth wets more, so water speed of infiltration to earth becomes slower, and large part of precipitation becomes surface run off, so some time on the slope area surface erosion causes. b) Iay and silt are easy to run off with the run off of water., Article, 信州大学農学部紀要 4: 1-62(1953)}, pages = {1--62}, title = {流出についての研究}, volume = {4}, year = {1953} }