title: Nutrients in soil solution following selective logging of a humid tropical 'terra firme' forest north of Manaus, Brazil.
abstract: Sustainable use of the Amazon forest for timber production is conditioned by the effect of logging on the system's nutrient cycling. This paper reports the results of a soil moisture and soil water chemistry monitoring campaign before and immediately after a selective logging which removed 35 m(3) wood/ha. Soil moisture was measured using tensiometers, and soil water chemistry using suction samplers in five disturbance classes: tractor tracks, clearing centres, clearing edges, forest edges and untouched forest. The results show that the soil under the tractor tracks and clearings contained more moisture than under the untouched forest. The suction samplers extracted substantially more nitrate, ammonium, calcium, magnesium and potassium from the clearing centres, the tractor tracks and the clearing edges than from the forest sites. The results are explained in terms of altered microbial activity, changes in crown interception and uptake by roots.
authors.affiliation: Projeto BIONTE, Institute Nacional de Pesquisas da Amazônia, Caixa Postal 478, Cep 69011-970, Manaus/AM, Brazil.
authors.forename: W
authors.initials: W
authors.lastname: Mello Ivo
authors.forename: S
authors.initials: S
authors.lastname: Ferreira
authors.forename: Y
authors.initials: Y
authors.lastname: Biot
authors.forename: S
authors.initials: S
authors.lastname: Ross