|Research article from ICN-UN|
|Written by Dennis Pedersen|
|Friday, 29 April 2011 07:03|
Impact of leaf harvest on populations of Lepidocaryum tenue, an Amazonian understory palm used for thatching
Jaime A. Navarro 1* , Gloria Galeano 1 and Rodrigo Bernal 1
1) Instituto de Ciencias Naturales, Universidad Nacional de Colombia, A.A. 7945, Bogotá, Colombia.
Leaves of the palm Lepidocaryum tenue are one of the most prized thatching materials in northwestern Amazonia. We studied the population dynamics of this stoloniferous palm in Colombian Amazonia, using ramet-based Lefkovitch matrices, and assessed the impact of leaf harvest on population structure and dynamics, through experimental defoliation. Leaf production rate of unharvested palms ranged between 0.93 leaves per year in seedlings and 1.71 in adults. Vegetative shoots produced through stolons are more important than seedlings for maintaining the population; stolons act also as a reserve to overcome damage in the population. The potential population growth rate was 8.3 % per year (λ = 1.083). Juveniles had the highest contribution to population growth, and permanence was the most important life parameter. Thus, harvest of leaves for thatching can jeopardize the population if juveniles are also harvested. An initial harvest intensity of more than 50% of the leaves in a crown, or leaving the palm with fewer than four leaves, would have a negative impact on leaf production. Although matrix modeling suggests that all adult ramets can be harvested, this must be taken with caution, as clonal integration may play an important role in population dynamics. Long-term harvest of Lepidocaryum leaves is possible, if plots are harvested in turns of four years, thus allowing palms to recover from the previous harvest. A better control on the quality of the braided tiles sold in the market would also ensure their longer duration, thus reducing the pressure on the resource.
|Last Updated on Friday, 29 April 2011 07:10|