Flooding tolerance of four tropical peatland tree species in a nursery trial

Abstract

In order to facilitate hydrological restoration efforts, initiatives have been conducted to promote tree growth in degraded and rewetted peatlands in Indonesia. For this initiatives to be successful, tree seedlings need to be able to survive flooding episodes, with or without shade. We investigated the survival of different shading and water levels under controlled conditions in a nursery, with artificial rainwater and with peat soils as the medium. The research focused on the fllowing questions (i) whether trees can grow on flooded peat soils; and (ii) which plant traits allow plants to cope with inundation, with or without shade. The four tree species compared ( Shorea balangeran, Cratoxylum arborescens, Nephelium lappaceum, and Durio zibethinus ) include two natural poineer and two farmer-preferred fruit trees. The experiment used as a split-split plot design with 48 treatment combinations and at least 13 tree-level replicates. The study found that S. balangeran and C. arborescens developed adventitious roots to adapt to the inundated conditions. D. zibethinus, S. balangeran and N. lappaceum grew best under moderate (30%) shading levels, while C. arborescens grew best in full sunlight.