Increased site fertility and litter decomposition rate in high-pollution sites in the San Bernardino Mountains

Abstract

Some possible factors causing enhanced litter decomposition in high-pollution sites in the San Bernardino Mountains of southern California were investigated. Nitrogen concentration of soil, as well as foliage and litter of ponderosa pine (Pinus ponderosa Laws.) and Jeffrey pine (Pinus jeffreyi Grev. & Balf.) were greater in high-pollution plots than in moderate- or low-pollution plots. Nitrogen concentration of soil, foliage, and litter of ponderosa pine (ozone-sensitive), and of the ozone-tolerant species, sugar pine (Pinus lambertiana Dougl.) and incense cedar (Calocedms decurrens [Torr.] Florin.), were all higher at a higher pollution site than at a moderate-pollution site. The rate of litter decomposition for all three species was also greater at the high-pollution site. Results suggest that the primary factor causing enhanced decomposition of L-layer litter in high-pollution plots is greater site fertility, leading to the production of foliage and litter that is higher in N than litter from moderate- or low-pollution plots.

Citation

Fenn, Mark E. 1991. Increased site fertility and litter decomposition rate in high-pollution sites in the San Bernardino Mountains. Forest Science 37(4):1163-1181