Leucaena macrophylla: An ecosystem services provider?

Abstract

Leucaena macrophylla, a tree native to southern Mexico’s tropical dry forest, belongs to a genus that is popular worldwide as a component of agroforestry systems. However, despite appreciation by local communities, this species is poorly studied and has not been evaluated as a multipurpose tree in its native range. This work evaluated whether L. macrophylla has the qualities necessary to serve as a multipurpose tree for agroforestry systems and a provider of ecosystem services in its original distribution, specifically, in soil nutrient amelioration and recovery, fuelwood production, and provision of quality livestock fodder. Leaves contained high values of nitrogen and calcium, and litter decomposition was relatively rapid (~50 % of mass lost over first 6 months). Despite somewhat low wood density, this species’ high calorific value and low ash and moisture contents yielded a relatively high firewood value index (FVI = 2,594.65), suggesting high potential as a fuelwood. In terms of fodder quality, protein and digestible fiber contents were high and in vitro digestibility was adequate, as was condensed tannin concentration. It is important to mention, however, that L. macrophylla showed higher-than-ideal contents of lignin, both in fresh leaves and in litter. However, this apparently does not drastically reduce overall quality (i.e. decomposition rate and in vitro digestibility), and appropriate management techniques such as composting can mitigate its effects. Given its potential for providing a variety of ecosystem services, we recommend that L. macrophylla be installed in agroforestry systems in its native range to evaluate its effect on crop productivity.