Restoration of Agriculture in Pinatudo Laser Areas
Grant-in-Aid for international Scientific Research
|Allocation Type||Single-year Grants|
|Research Institution||TOHOKU UNIVERSITY|
NANZYO Masami Faculty of Agriculture, Tohoku University Associate Professor, 農学部, 助教授 (60218071)
メンドーザ D フィリピン大学, 農学部, 助教授
SAMONTE Henry P. Faculty of Agriculture, University of Philippines, 農学部, 教授
KANNO Hitoshi Faculty of Agriculture, Tohoku University, 農学部, 助手 (30250731)
KIMURA Kazuhiko Faculty of Agriculture, Tohoku University, 農学部, 助手 (10183302)
ITO Toyoaki University Farm, Tohoku University, 附属農場, 助教授 (10176349)
MIZUNO Tadaharu Dep. of Dairy Farming, Hokkaido College of Arts, 酪農科, 教授 (90229708)
KANAZAWA Shinjiro Faculty of Agriculture, Kagoshima University, 農学部, 助教授 (10011967)
CHINO Mitsuo Faculty of Agriculture, Tokyo University, 農学部, 教授 (10007677)
MENDOZA Danilo Faculty of Agriculture, University of Philippines
|Project Period (FY)
Completed(Fiscal Year 1995)
|Budget Amount *help
¥3,300,000 (Direct Cost : ¥3,300,000)
Fiscal Year 1995 : ¥3,300,000 (Direct Cost : ¥3,300,000)
|Keywords||Mt. Pinatubo / Lahar / Volcanic ash / Corn / Rice / Controlled availability fertilizer / Pioneer plant / Agriculture|
In 1991, Mt. Pinatubo, Phillipines erupted and a large amount of volcanic ash deposited in the Zambales Mountain Area. The deposit of volcanic ash is eroded down to the agricultural area of the Central Plain of Luzon as lahar in the rainy season. About 90,000 ha of agricultural and residential areas were affected by the lahar deposits and the hazard was still continuing in the rainy season of 1995.
Survey of the lahar deposits and pioneer plants in the lahar-affected area was carried out in Bamban valley, Tarlac Province. The lahar deposits consist of almost pure volcanic ash. The rock type of the volcanic ash is dacitic to andesitic. The major mineral components are non-colored volcanic glass and feldspar. Qualtz, hornblend, magnetite, and biotite was included as minor minerals. Since the content of available phosphorus by Truog's method was as high as 50-60 mgP_2O_5/100g, apatite was considered to be included in the volcanic ash.
Particle size distribution was coarse-sandy to silty. Although the silty materials contained 10 to 15% of clay, the major minerals in the clay fraction was volcanic glass. Very small amount of smectite, vermiculite and halloysite was also included in the clay fraction. The content of halloysite was highly variable.
Major pioneer plant was wild sugarcane with lesser population of leguminous plants. Population of these pioneer plants was high in the far places from the major lahar stream and was low in the major stream where deposition and erosion is repeated frequently.
Rice, corn, and peanut cultivation was examined using controlled-availability fertilizers (CAFs) in the concrete plots filled with lahar deposits. CAFs were effective for corn plants in the infertile and coarse-textured lahar deposits. In the rice plots, plant growth was not so good even in the CAFs plot due to iron deficiency.
Research Products (4results)