Aboveground Biomass and Nutrients in Young Plantations of Indigenous Trees on Infertile Soils in Costa Rica

Abstract

Aboveground-tree biomass and nutrient content (nitrogen, phosphorus, calcium, magnesium and potassium) were measured in Cvear-old stands of four indigenous tree s~ecies: Smuhnodendron micr&tachywn Pcepp. et .End]. (gx S. excels& Harms), ~ochysia gua-remaIemis Donn. Smith (ex I! hondurensis S m m e ) , Vochysia f e m i ---. nea Mart and ~~e r o n i h alchorneoides (0), growing on hferiile 6 1 s in an experimental plantation in the Atlantic humid lowlands of Costa Rica Biomass and nutrient content among Ihe species, and among aboveground w e parts, forest-floor litter and understory vegelation were compared, as key factors that can be manipulated with different effects on site nubient conservation. Biomass and stemwood annual increments of the four species were similar to those reported for ocher Florencia Montagnini is Associate Rofessor of Tropical Ecology, Yale University, School of Forestry and Environmental Studies, 370 Rospect Street, New Haven. CT 065 11. JOURNAL OF SUSTAINABLE FORESTRYtropical tree plantations in the humid tropics. S. microstach~wn had the highest accumulation of N in stem, branch and total aboveground tree biomass. L! guatemalensis had the highest accumulation of Ca and Mg in the biomass, while H. alchomeoides had the highest stem K and P. In spite of heir relatively lower N tissue collcentrations. V. ferruginea and H. alchorneoides showed a high potential for N recycling due to its more even distribution in stems, branches and leaves. Nument accumulation by the understory in S. microstachywn and H. alchorneoides plots was 0.8-7.746 of aboveground see biomass numents.?he forest-floor litter repsented a major compartment for nutrient accumulation and recycling under the four species, especially for N, Ca, Mg and P.

Seed rain under tree islands planted to restore degraded lands in a tropical agricultural landscape

“…Trees also facilitate movement of birds and bats through agricultural landscapes (McDonnell and Stiles 1983, Nepstad et al 1991, Estrada et al 1993, Guevara and Laborde 1993, Wunderle 1997, Harvey 2000b). In addition, trees serve to overcome a range of barriers to seedling establishment by shading out competitive grasses (Parrotta 1992, Guariguata et al 1995, ameliorating microclimatic conditions (Guevara et al 1992, Parrotta 1995, Holl 1999, Nepstad et al 1999, and improving soil chemical and physical properties (Sanchez et al 1985, Montagnini and Sancho 1994, Ashton et al 1997. Establishing and maintaining plantations of trees, however, can be an expensive and labor-intensive endeavor.…”