Emergy of tree agroforestry systems in southern Lempira, Honduras

摘要

Resource use and sustainability of three agroforestry systems (Secondary Woods – BS; Fell and Burn – TQ; and Quesungal Conservation mode – SAQ) were evaluated by analyzing data from fifteen 200 m2 plots (14° 05' N; 88° 30' W), making use of transformity values reported in other related studies. The highest emergy values were observed for the variable rain (1.35E15 sej/ha per year); and the largest emergy differences were found in eroded soils, especially those of TQ. BS and SAQ exhibited a greater Environmental Load Ratio than TQ (0.63, 0.14 and 0.02, respectively). TQ showed the largest Ecological Footprint Index value, followed by SAQ and BS. Emergy Sustainability Index for TQ was 34.8, whereas SAQ and BS reached respective values of 135.6 and 4,123.8. The latter two data, as compared to the former, reveal how these systems (SAQ and BS) favor the use of local renewable resources.