Revista Chilena de Historia Natural 76 (3): 437-449, 2003
RESEARCH ARTICLE
Biomass partitioning and leaf area of Pinus radiata trees subjected to
silvopastoral and conventional forestry in the VI region, Chile
The effects of silvicultural regimes on leaf area and biomass distribution were analyzed in
16-year old Pinus radiata trees growing in the semiarid zone of Chile. Three stands with different silvopastoral
management were compared with a conventionally managed stand. Data were obtained through destructive sampling of
36 trees and analyzed by MANOVA and regression models of ANCOVA. Results show that the management
regime affects the leaf area. Specific leaf area was affected by both silvicultural regime and crown position. Total
biomass per tree under the silvopastoral regime was 2.1 to 2.5 times larger than in the conventional forestry regime.
However, aboveground biomass partitioning was neither affected by the silvicultural regime nor by the schemes of
silvopastoral management. The most important allometric change was in fine root biomass, which was greater under the
conventional forestry regime than in the silvopastoral one. Fine root biomass increases with a regular distribution of the
plants in the field, and decreases with the clumping of trees. Similarly, the fine root biomass decreases with fertilization.
Both plantation design and fertilization regimes explain the changes in the fine root biomass to components of the crown.
However, crown structure influences the magnitude of these changes.
Key words:
leaf area, biomass,
silvopastoral management, Pinus radiate
