The Effect of Soil Erosion Control by Pineapple Vegitation on Pineapple Orchard (Fundamental Studies on Farm land Conservation in Okinawa IX.) (Department of Agricultural Engineering)

以上の結果を要約すると次のとおりである。1.調査したパインアップルの根群域は深さにおいて20cm程度, 広がりは根株を中心として半径約40cmの範囲にあり, 根は土壌硬度約25mmの所まで伸びている。2.供試株根65個全体の緊縛強度の平均値は31kgであるが, 生育令36ケ月までのものについては緊縛強度との間に極めて高い相関関係(r=0.923)がある。3.被覆率は被覆巾(縦・横)の積の関数として表わされ, 両者の間には極めて高い相関(r=0.865)がある。4.生育令3ケ月と10ケ月の供試株1個の平均被覆面積はそれぞれ1242cm^2,2788cm^2で, 栽植様式を4000本/10α(密植型)とすると被覆率は50%, 110%となる。The purpose of this study is to investigate the effect of erosion control by pineapple vegetation. In the present paper the author measured the soil holding capacity of pineapple roots and the degree of vegetative cover of pineapples. The results obtained are as follows : 1. The distribution of pineapple roots is 20cm deep and almost 40cm wide around the stem. 2. The average soil compact strength of the sample is 31kg and there is a very high correlation (r=0.923) between the age (under 36 months old) of a pineapple and it's root strength. 3. The covering ratio of a pineapple is described as the function of projective width and there is a very high correlation (r=0.865) between the two. 4. A sample shows that the projective covering areas of the age of 3 month and 10 month are 1242(cm)^2,and 2788(cm)^2,and their covering ratios are 50% and 110% under the densely cropped condition (4000stem/10a) respectively