Treesearch

Plant community succession alters the quantity and chemistry of organic inputs to soils. These differences in organic input may trigger changes in soil fertility and fauna1 activity. We examined earthworm density and community structure along a successional sequence of plant communities in abandoned tropical pastures in Puerto Rico. The chronological sequence of these plant communities were pasture, grass-vine-fern, shrub-small tree, and forest. Earthworm density was the highest in pasture (831 worms m-’ in top 0.25 m soil), decreased as secondary succession proceeded, and reached the...

Patterns of plant and animal diversity were studied in a 10-year-old native species reforestation area at a bauxite-mined site at porto Trombetas in western Para State, Brazil. Understorey and overstorey floristic composition and structure, understorey light conditions, forest floor development and soil properties were evaluated in a total of 38 78.5-m2

(IITF-SM; 80 ). Notes: Part of the Silvics Manual Series, under SO-ITF-SM.

Abundance of the Puerto Rican Vireo (Vireo Zutimeri) in Guanica Forest, Puerto Rico, has declined gradually over the period 1973-1996 as determined by constant effort mist netting. Concurrent studies of breeding vireos show low nesting success, primarily due to parasitism by Shiny Cowbirds (Molothrus bonariensis). This decline may reflect the rather recent entry of the cowbird into Guanica Forest during the breeding season, as other factors (vegetation change, rainfall) do not seem to explain the decline. As a single island endemic, it is important that the cause of this decline be...