三田市フラワータウンにおける孤立二次林と土壌環境

抄録

The distribution of dominant forest types, their community structures and soil conditions were investigated in the fragmented secondary forest on a hill slope in Flower Town, Sanda City, Hyogo Prefecture, Japan. The dominant tree species in the fragmented secondary forest were Pinus densiflora at the top and upper part of slope, and Quercus serrata at the lower part of slope. Pinus densiflora was distributed on the thin and hard soil. On the other hand, Quercus serrata was distributed on the thick and soft soil. The forest vegetation of the fragmented secondary forest was classified into the following three forest types on the basis of their physiognomy and vegetation height: 1. Medium-tree Pinus forest (height 10-13m ; younger), 2. Tall-tree Pinus forest (height 16-18m), 3. Quercus forest. Surface soil moisture status (measured by tensiometric method) was compared among the three forest types. The soil moisture status of vegetation types in heavy-rainfall term maintained a lower level of under pF value 1.8. In light-rainfal lterm, it maintained a higher level of more than pF value 1.8, in the order of Plot No.l (Medium-tree Pinus forest), Plot No.2 (Tall-tree Pinus forest), Plot No.3 (Quercus forest).