Microclimate and nutrient dynamics in a silvopastoral system of semiarid northeastern Brazil

• Published in: Agroforestry systems Vol. 56; no. 1; pp. 27 - 38
• Main Authors: MENEZES, R. S. C, SALCEDO, I. H, ELLIOTT, E. T
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer 01.10.2002; Springer Nature B.V
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Chemical, physicochemical, biochemical and biological properties; Fundamental and applied biological sciences. Psychology; Grasses; Litter; Microclimate; nutrient dynamics; Organic matter; Pasture; Physics, chemistry, biochemistry and biology of agricultural and forest soils; plant biomass; Prosopis juliflora; Soil; Soil moisture; Soil science; Soils; Trees; Ziziphus; South America; Brazil; America; Neotropical Region; Monocotyledones; Silvopastoral system; Tropical zone; Cenchrus ciliaris; Biogeochemical cycle; Microclimate; Prosopis juliflora; Multipurpose tree; Agroecosystem; Nitrogen cycle; Leguminosae; Gramineae; Organic matter cycle; Mineralization; Semi arid zone; Dicotyledones; Angiospermae; Nutrient; Spermatophyta; Fruit tree; Fodder crop; Rhamnaceae; Agroforestry; Grassland soil
• ISSN: 0167-4366; 1572-9680
• DOI: 10.1023/A:1021172530939

There is little available information on nutrient cycling and the controls of ecosystem processes in land use systems of dry neotropical regions. In this study, we conducted field and glasshouse experiments to investigate the influence of Ziziphus joazeiro and Prosopis juliflora trees on microclimate and nutrient dynamics in pastures ofCenchrus ciliaris in semiarid northeastern Brazil. We found that soil moisture was lower under the crowns of P. juliflora trees during early season in comparison to patches ofC. ciliaris (grass patches), but the presence of Z. joazeiro had no effect on soil moisture. Soil and air temperatures were lower under Z. joazeiro in comparison to grass patches but P. juliflora had little effect on temperature. Losses of P from all litter types were lower under the crowns of Z. joazeiro trees, but losses of biomass and N from litter were not consistently affected by the presence of trees. Soil net N mineralized was greater under both tree species, in comparison to grass patches. However, net soil N mineralized per gram of total soil N was greater under the crowns of the potentially N^sub 2^ fixing P. juliflora, in comparison to grass patches, while there were no significant differences betweenZ. joazeiro crowns and grass patches. In the glasshouse study, plant biomass and nutrient uptake was greater in soil collected under the crowns of both tree species, in comparison to soil from grass patches. Our results indicate that the preservation of native trees or introduction of exotic tree species in C. ciliaris pastures in semiarid northeastern Brazil significantly affects microclimate and the dynamics of litter and soil nutrients, and may contribute to increases in the cycling rate of nutrients in these systems. Index terms: buffel grass, caatinga, nitrogen mineralization, Prosopis juliflora, Ziziphus joazeiro.[PUBLICATION ABSTRACT]