Long-term declines in nutritional quality of tropical leaves.

Journal Article (Journal Article)

Global change is affecting plant and animal populations and many of the changes are likely subtle and difficult to detect. Based on greenhouse experiments, changes in temperature and rainfall, along with elevated CO2, are expected to impact the nutritional quality of leaves. Here, we show a decline in the quality of tree leaves 15 and 30 years after two previous studies in an undisturbed area of tropical forest in Kibale National Park, Uganda. After 30 years in a sample of multiple individuals of ten tree species, the mature leaves of all but one species increased in fiber concentrations, with a mean increase of 10%; tagged individuals of one species increased 13% in fiber. After 15 years, in eight tree species the fiber of young leaves increased 15%, and protein decreased 6%. Like many folivores, Kibale colobus monkeys select leaves with a high protein-to-fiber ratio, so for these folivores declining leaf quality could have a major impact. Comparisons among African and Asian forests show a strong correlation between colobine biomass and the protein-to-fiber ratio of the mature leaves from common tree species. Although this model, predicts a 31% decline in monkey abundance for Kibale, we have not yet seen these declines.

Full Text

Duke Authors

Cited Authors

  • Rothman, JM; Chapman, CA; Struhsaker, TT; Raubenheimer, D; Twinomugisha, D; Waterman, PG

Published Date

  • March 2015

Published In

Volume / Issue

  • 96 / 3

Start / End Page

  • 873 - 878

PubMed ID

  • 26236882

Electronic International Standard Serial Number (EISSN)

  • 1939-9170

International Standard Serial Number (ISSN)

  • 0012-9658

Digital Object Identifier (DOI)

  • 10.1890/14-0391.1

Language

  • eng