Encyclopedia of soils science / Энциклопедия наук о почвах

This entry explains the use of emergy analysis to evaluate systems and compare resource use, environmental loading, and sustainability. This method allows the free contributions of the environment to be compared directly with the purchased inputs from the economy. Results summarized from agriculture and forestry systems indicate that extensive amounts of indirect energy were dissipated to yield agricultural and forest products and that timber typically requires less indirect energy than crops.

Timber production had higher average yields than agricultural crops, demonstrating that forests yield a greater amount of solar emergy per unit of economic input than crop systems. The average environmental loading of agricultural crops was greater than that of forests, revealing that crop production relies much more heavily on non-renewable and purchased inputs than forestry. Finally, the sustainability of forestry systems was much greater than crops, indicating that forests are more sustainable than cropland. <...>