Carbon Sequestration in Pastures, Silvo-Pastoral Systems and Forests in Four Regions of the Latin American Tropics

background

77% of agricultural land in the tropical Americas is used for pasture (including silvo-pasture and Argo-silvo-pasture), making carbon stocks in this land type an important consideration. This paper presents three-year research results on the evaluation of soil carbon stocks (SCS) in long-established pasture and silvo-pastoral systems (10-16 years under commercial production), native forests and degraded land in four regions of tropical Americas.

research goals & methods

In the tropical Andean hillsides, Colombia, SCS from pastures were statistically lower than those from native forest, but higher than those from natural regeneration of a degraded pasture (fallow land), degraded pasture and mixed-forage bank. In contrast, in the humid tropical forest of the Atlantic Coast, Costa Rica, pasture or silvo-pastoral systems with native or planted pasture species showed statistically higher SCS than native forest. Similar rankings were found in the humid tropical forest of Amazonia, Colombia where improved Brachiaria pastures (monoculture and legume-associated) showed statistically higher SCS than native forest. In the sub-humid tropical forest of the Pacific Coast, Costa Rica no statistical differences in SCS were found between land-use systems.

conclusions & takeaways

In tropical ecosystems, improved pasture and silvo-pastoral systems show comparable or even higher SCS than those from native forests, depending on climatic and environmental conditions, and represent attractive alternatives as C-improved systems.