Atributos físicos, químicos e biológicos de um Latossolo de cerrado em plantio de espécies florestais

Abstract

Resumo -O objetivo deste trabalho foi avaliar o impacto de plantios fl orestais nos atributos físicos, químicos e biológicos de um Latossolo Vermelho-Amarelo de cerrado. Amostras de solo foram coletadas à profundidade de 0 a 10 cm, em áreas cultivadas há mais de 20 anos com pínus (Pinus tecunumanii), eucalipto (Eucalyptus grandis) ou carvoeiro (Sclerolobium paniculatum). Uma área adjacente de cerrado nativo foi incluída como referência do solo original. Foram observados, em relação ao cerrado, aumentos na densidade do solo sob pínus e eucalipto, redução na macroporosidade sob pínus, menores teores de matéria orgânica sob pínus e eucalipto, além de decréscimos no pH e na saturação por bases e incremento da saturação por alumínio nos cultivos com pínus e carvoeiro. O carbono da biomassa microbiana sob pínus, eucalipto e carvoeiro foi aproximadamente a metade do carbono sob cerrado. Atividades de fosfatase ácida e arilsulfatase foram inibidas pelo pínus e estimuladas pelo carvoeiro. Entre os refl orestamentos avaliados, o pínus promoveu a redução mais acentuada da qualidade do solo de cerrado. As variáveis microbiológicas foram as mais sensíveis em detectar o efeito dos diferentes refl orestamentos na qualidade do solo.Termos para indexação: Eucalyptus grandis, Pinus tecunumanii, Sclerolobium paniculatum, carbono da biomassa microbiana, enzimas do solo, qualidade do solo. Physical, chemical and biological attributes of a cerrado Oxisol under different forest speciesAbstract -The objective of this study was to evaluate the impact of forest plantations on the physical, chemical and microbiological attributes of a cerrado Oxisol. Soil samples were collected at 0-10 cm depth from sites cultivated with pinus (Pinus tecunumanii), eucalyptus (Eucalyptus grandis) and carvoeiro (Sclerolobium paniculatum) for over 20 years. An adjacent native cerrado area was used as a reference of the original soil conditions. It was observed in relation to the native cerrado: increases in soil density under pinus and eucalyptus, reduction in the macroporosity under pinus, lower organic matter contents under pinus and eucalyptus, besides decreases in the soil pH and in the base saturation under pinus and carvoeiro along with an increase in aluminum saturation. Soil microbial biomass carbon under the pinus, eucalyptus and carvoeiro sites was about half of that found under cerrado. The activities of acid phosphatase and arylsulfatase were inhibited by pinus and stimulated by carvoeiro. Among the forest systems evaluated, pinus promoted the greatest reduction on soil quality. The microbiological variables were the most sensitive to detect the effects of these systems on soil quality.

Chemical and Microbiological Attributes Under Different Soil Cover

“…This was also observed by Cardoso et al (2011) in an area of grazing land converted from woody vegetation; by Liu et al (2002) who studied the effect of natural forest, grassland, shrub, secondary forest as forest on soil properties; and by Silva et al (2009) who studied the attributes of a Cerrado Oxisol planted with forest species. According to Gama-Rodrigues et al (2008a), the non-variability of P available in soils under different types of vegetation is associated with the robust stabilization of this element in highly weathered soils.…”

“…Studies with chronosequences of forest to pasture areas in the Amazonia region have shown that the microbial biomass reduced in the soil after three years of establishment of pastures (CENCIANI et al, 2011) and change in the composition of the microbial community (LAMMEL et al, 2015). Similar results were also observed by Silva et al (2009) who reported that MB-C under managed forest was about half of that found under Cerrado. Changes in MB are connected to components of the vegetation, in particular diversity.…”

Relationships between microbial activity and soil physical and chemical properties in native and reforested Araucaria angustifolia forests in the state of São Paulo, Brazil

“…The MBC indicates changes in the soil ecosystem balance (Baretta et al, 2005(Baretta et al, , 2008Silva et al, 2009;Baretta et al, 2010;Kaschuk et al, 2010). The MBC values found in this study were almost double those reported by Baretta (2007) and Bertini (2010) and are within the range of values found by Carvalho et al (2012) in soils under native and reforested Araucaria forests in the State of São Paulo, and within the range found for ecosystems of Atlantic forest (683 -1520 mg C kg -1 soil) (Kaschuk et al, 2010).…”

Biomassa e atividade microbiana em solo sob diferentes sistemas de manejo na região fisiográfica Campos das Vertentes - MG

“…Além dos efeitos associados à remoção da vegetação nativa e intensidade de manejo do solo, as reduções no Cmic, possivelmente, também refletiram alterações associadas à quantidade e à qualidade dos resíduos vegetais disponíveis à microbiota (Gama-Rodrigues et al, 2008;Silva et al, 2009). Isso ficou mais evidente principalmente no sistema CCE, que, apesar de ausência de manejo do solo após o plantio do eucalipto, ainda apresentou Cmic significativamente inferior ao do CN, notadamente na profundidade de 0-10 cm (Quadro 3).…”