Restoration for increasing biodiversity in areas intended for
sustainable use faces several challenges. One major challenge is developing
strategies that minimize restoration costs while increasing effectiveness, being
at the same time culturally acceptable for those implementing them.
The current research focused on restoration of diverse pine forests in abandoned
agricultural fields being reforested for sustainable timber extraction. The
effect of Lupinus elegans patches on
understory plant species richness was tested at two different scales, the patch
scale and the site scale. Lupinus elegans
was chosen because is a successional legume species that traditionally is
recognized for its soil improvement capabilities.
At the patch scale, species richness was higher at patch borders (20 ± 1 species), than within patches (17 ±
1 species) or control plots (18 ± 1 species). At the site scale, our
restoration site had the highest number of understory species after two years
with 57 species, in contrast neighboring sites had only 12 species and 19 species. The
closest forest remnant had 36 species. In our
restoration site several species were present that were absent in neighboring
reforestation sites in particular bird dispersed species, such as Solanum
spp and Crataegus pubescens.
Spontaneous recruitment tree species also occurred (Pinus pseudostrobus and Crataegus pubescens). Soil nitrogen
increased within Lupinus elegans
patches (59 kg/ha) and control patches (55.7 kg/ha) in
comparison with initial soil concentrations (42.7 Kg/ha).
Our results suggest that use of species that play relevant ecological
and cultural roles in restorations are an efficient strategy for increasing
diversity.