Planting mahogany in canopy gaps created by commercial harvesting |
| |
Authors: | J. do C.A. Lopes S.B. Jennings N.M. Matni |
| |
Affiliation: | 1. Embrapa Amazônia-Oriental, CP 48, Belém, Pará 66.095-100, Brazil;2. Oxfam GB, Oxfam House, John Smith Drive, Oxford OX4 2JY, UK;3. Nordisk Timber Ltda., CP 1541, Belém, Pará 66.820-000, Brazil |
| |
Abstract: | Attempts at natural forest management of mahogany (Swietenia macrophylla King) have so far met with limited success, whilst many plantations are beset by the shoot borer Hypsipyla spp. In this paper we present preliminary results of an approach to enrichment planting that aims to balance economic returns (rapid growth and good silvicultural form) with intervention costs and changes to forest structure. Mahogany seedlings were planted in gaps created by selective timber harvesting and that ranged in vertical projected area from 91 to 542 m2 (mean = 257 m2). Seedlings grew within the matrix of gap regrowth, with limited control of competing vegetation. Sixty-one percent of seedlings had survived by 4.4 years (equivalent to an annual mortality rate of 10.5% year−1), and had reached a mean height of 4.5 m. Stocking levels of mahogany were similar to that of naturally regenerated commercial species in unplanted gaps of the same age, but mahogany seedlings were significantly taller. The incidence of shoot borer attack on mahogany stems was relatively low (54.7%), but, more importantly, most damaged stems (58%) responded by producing a single replacement leader. The cost of the proposed methodology (US$ 94 per gap over 4.4 years) was low compared to the high value of mahogany timber relative to other species in the forest. The implications of planting mahogany in gaps for forest management and the potential benefits to conservation of the species are considered. |
| |
Keywords: | Brazilian Amazon Canopy gaps Height growth Hypsipyla Silviculture Swietenia macrophylla |
本文献已被 ScienceDirect 等数据库收录! |
|