CAATINGA AND THE OPPORTUNITY IN MITIGATING GREENHOUSE GAS EMISSIONS BY AGRO-PASTORAL ACTIVITIES

Abstract

Climatic changes caused by anthropogenic greenhouse gas emissions are the most significant themes at present. Agriculture and livestock have been identified as one of the sources of greenhouse gas emissions. This is especially true for cattle due to their emission of methane (CH4), enterically-derived and from wastes, and to the emission of nitrous oxide (N2O) from pastures and grain production. Methane from ruminants is mainly the product of processes involving microorganisms in the rumen. They use nutrients from ingested food as substrates and produce several compounds as products of metabolism, methane included. The emission of methane is therefore directly related to ruminant animals´ diet. The emission of nitrous oxide is related to animals´ solid and liquid wastes through the transformation of urine-urea into N2O. Feeding methods have to be more efficient and adequate, warranting the rumen´s correct functioning, so that the product of ruminant animals would be more efficient, sustainable and environmentally friendly. The Brazilian caatinga or shrubland has a wide range of trees and shrubs, and, therefore, forage sources with different characteristics from those of the common pastureland. The above is due to nutritional aspects such as compounds derived from secondary metabolism of vegetal species which may be directly perceived in the animal´s performance and methane emission.