森林立地学会誌 森林立地50(2), 2008, 141〜152
Jpn.J.For.Environment 50(2), 141−152 2008
Rehabilitation of degraded tropical rainforest in Peninsular Malaysia with
a multi-storied plantation technique of indigenous dipterocarp species
Arifin Abdu1)・Sota Tanaka2)・ Shamshuddin Jusop3)・ Nik Muhamad Majid4)
Zahari Ibrahim5)・Katsutoshi Sakurai6)
1) The United
Graduate School of Agricultural Sciences, Ehime University
2) Graduate
School of Kuroshio Science, Kochi University
3) Faculty of
Agriculture, University Putra Malaysia
4) Faculty of
Forestry, University Putra Malaysia
5) Forestry
Department Peninsular Malaysia
6) Faculty of
Agriculture, Kochi Uninersity
The rehabilitation of degraded tropical rainforest was
studied in the Chikus Forest Reserve, Perak,
Peninsular Malaysia. Growth performance and soil fertility status were assessed
for two indigenous dipterocarp species, Shorea
leprosula and S. parvifolia
planted under a secondary forest in
1994 and under an abandoned Acacia
mangium plantation in 1992 with a multi–storied plantation technique. The
assessment was conducted with a special reference to two indices; soil
fertility index (SFI) and soil evaluation factor (SEF), which are commonly used
for soil fertility assessment in relation to the succession of secondary forests
in humid tropical regions. The results showed that among various
inter-spacing planting, moderate planting spacing of 20 m in the secondary
forest and 15 m in A. mangium plantation
resulted in most favorable growth of both species. The significant correlation
between SFI and growth performance suggested that the applicability of the SFI
as an index for estimating soil fertility and site quality for rehabilitation
of degraded forestland with a multi-storied plantation technique. However, any
correlation was not found with the SEF. It is concluded that, the soil
fertility status evaluated by the SFI can play an important role for
determining the growth of planted dipterocarp species.
Key words: Acacia mangium plantation, forest rehabilitation, growth performance,
multi–storied forest, site quality, soil fertility
Arifin Abdu・田中壮太・Shamshuddin Jusop・Nik Muhamad Majid・Zahari Ibrahim・櫻井克年:在来フタバガキ樹種を用いた複層植林技術による半島マレーシアの荒廃熱帯雨林の修復
マレーシア・ペラ州チクス森林保護区において,荒廃した熱帯雨林の修復を目的とした複層植林技術による植林試験の評価を行った。二次林および放棄されたAcacia mangium植林地に植栽された在来フタバガキ2種(Shorea leprosula,S. parvifolia)について,二次林では12年後の,A. mangium植林地では14年後の生育状況を調べた。同時に土壌分析を行い,土壌肥沃度指標(soil fertility index, SFI)と土壌評価因子(soil evaluation factor, SEF)を算出した。これらの指標は,一般に,湿潤熱帯地域の二次林植生の遷移に関連して使用されているものである。植林試験は,さまざまな植栽間隔で行われたが,二次林では20mの間隔で,一方,A. mangiumでは15 mで,植栽樹の生育は最も良好であった。SFIについて土壌肥沃度と植栽樹の生育に有意な相関関係が認められことから,複層植林技術による植林において,SFIは,土壌肥沃度と地位評価の有効な指標となりうることが示唆された。一方,SEFには,そのような関係はみられなかった。これらのことから,林冠下の光強度に加えて,SFIにより評価される土壌肥沃度が,フタバガキ植栽樹の生育に重要であると考えられた。