Evaluation of Inhibitory Effect by Adaptation Measures for Red Soil Runoff from Farmland due to Heavy Rainfall
Noriyuki Yasufuku*, Kohei Araki**, Kiyoshi Omine***, Kenichiro Okumura*, and Kohei Iwami*
744 Motooka, Nishi-ku, Fukuoka, Japan
**University of Yamanashi, Yamanashi, Japan
***Nagasaki University, Nagasaki, Japan
As the climate begins changing due to global warming, heavy rainfalls have become more frequent. These are, in turn, increasing the red soil runoff that has increasingly damaged the marine products and tourist industries. Over 85% of all such runoff is from farmland. Working with local farmers, we conducted field experiments in Ginoza Village in Okinawa’s Matsuda district to better understand the inhibitory effects on red soil runoff of different potential adaptation measures. Effectiveness of the adaptation methods conducted are discussed based on the obtained results. Further, a physical model is presented for simply estimating the sediment volume due to soil erosion by using the grain size distribution. The model can give a good agreement with the measured maximum particle sizes of the red soils discharged from farmland.
-  Japan Meteorological Agency, “Rainfall intensity and form” (in Japanese), http://www.jma.go.jp/jma/kishou/know/yougotextunderscore hp /mboxamehyo.html [accessed March 22, 2015]
-  K. Araki, K. Okumura, N. Yasufuku, and K. Omine, “Studies on the inhibitory effect by various adaptation measures for red soil runoff from farmland on field tests, Unsaturated Soils : Research & Applications,” 6th Int. Conf. on Unsaturated Soils (UNSAT2014), pp. 1447-1452, 2014.
-  K. Okumura, K. Araki, N. Yasufuku, K. Omine, and K. Iwami, “Evaluation of the various adaptation measures to inhibit the red soil runoff based on field test,” JS-Okinawa 2013 7th Int. Joint Symposium on Problematic Soils and Geoenvironment in Asia, pp. 25-30, 2013.
-  Okinawa Prefectural Government, Department of Environmental and Community Affairs, Environmental Preservation Division, “Outline of Okinawa prefecture red soils runoff prevention measures basic plan,” p.1 (in Japanese), http://www.pref.okinawa.lg.jp /site/kankyo/hozen/documents/02textunderscore kihonkeikakutextunderscore gaiyoutextunderscore 131213 .pdf [accessed March 22, 2015]
-  Okinawa Prefectural Government, Department of Environmental and Community Affairs, Environmental Preservation Division, “Summary version of commissioned business report of sea areas monitoring survey for red soils runoff prevention,” p.3.2-12(58) (in Japanese), http://www.pref.okinawa.jp/site/kankyo/hozen/mizu textunderscore tsuchi/h25redsoilmonitoringresult.html [accessed March 22, 2015]
-  Y. Kanda, (in Japanese), http://www.inamori.kagoshima-u.ac.jp /kanda/ronbuntextunderscore activity03textunderscore 02textunderscore 02.html [accessed March 22, 2015]
-  K. Araki, K. Okumura, N. Yasufuku, and K. Omine, “A consideration on inhibitory effect of red soil runoff by various adaptation measures on field tests,” 10th JGS Symposium on Environmental Geotechnics, pp. 221-226, 2013 (in Japanese).
-  K. Okumura, K. Araki, N. Yasufuku, K. Omine, and H. Hazarika, “Studies on the inhibitory effect of red soil runoff by various adaptation measures on field tests,” Int. Joint Symposium on Urban Geotechnics for Sustainable Development, pp. 140-143, 2012.
-  K. Araki, K. Okumura, N. Yasufuku, and K. Omine “Proposal of a method for probabilistic evaluation of the volume change during the centrifugal water retention test,” JGS Symposium on Uncertainty at Soil Testing and Surveying, pp. 101-108, 2012 (in Japanese).
-  K. Iwami, K. Araki, N. Yasufuku, R. Ishikura, H. Hazarika, and K. Okumura, “Basic study on surface water and grain size distribution of red soil runoff,” 68th JSCE Annual meeting, 2013 (in Japanese).
-  Japan Meteorological Agency, http://www.data.jma.go.jp/obd/stats/ etrn/index.php?prectextunderscore no=91&blocktextunderscore no=1374&year=&month=& day=&view [accessed March 22, 2015]
-  N. Yasufuku, K. Omine, K. Araki, and K. Murayama, “Introduction of adaptation Measures to prepare for increasing of the risk of red soil runoff due to climate change,” 9th JGS Symposium on Environmental Geotechnics, pp. 201-206, 2011 (in Japanese).
-  S. Ikeda, “Watershed management and red clay out suppression system related research and development in Okinawa,” AJSCE in 2004fy “priority research agenda” report, pp. 1-23, 2004 (in Japanese).
-  T. Shiono, K. Tamashiro, N. Haraguchi, and T. Miyamoto, “Use of vegetation filter strips for reducing sediment discharge during a rainstorm, participatory strategy for soil and water conservation,” Institute of Environmental Rehabilitation and Conservation, pp. 55-58, 2004.
-  K. Araki, N. Yasufuku, K. Murayama, K. Omine, and H. Hazarika, “Modeling for outflow of soil sediments considering grain size distribution,” The 2nd Japan-Korea Joint Workshop on Unsaturated Soils and Ground, pp. 151-160, 2011.
-  K. Iwami, K. Araki, N. Yasufuku, and K. Vilayvong, “Characteristics of Red Soil Loss during Short Time Heavily Rain,” JS-Okinawa 2013 7th Int. Joint Symposium on Problematic Soils and Geoenvironment in Asia, pp. 131-134, 2013.
-  K. Iwami, K. Araki, N. Yasufuku, R. Ishikura, and H. Hazarika, “Soil runoff model and its application by focusing soil particle mechanics equilibrium,” JSCE-west annual meeting, No.III-86, 2015 (in Japanese).
-  D. Gallipoli, A. Gens, J. Vanet, and E. Romero, “Role of Degree of Saturation on the Normally Consolidated Behavior of Unsaturated Soils,” Proc. 3rd Int. Conf. on Unsaturated Soils, pp. 115-120, 2002.
-  H. Yamaguchi, “Soil Mechanics,” Gihodoshuppan, pp. 38-40, 2004.