alculate NEP before the outbreak and identify the most appropriate conclusion about whether the forest was a carbon sink or a carbon source. Calculate NEP before the outbreak and identify the most appropriate conclusion about whether the forest was a carbon sink or a carbon source. Before the outbreak, the forest was a carbon sink because NEP was less than 0. Before the outbreak, the forest was a carbon sink because NEP was greater than 0. Before the outbreak, the forest was a carbon source because NEP was less than 0. Before the outbreak, the forest was a carbon source because NEP was greater than 0.