Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.

Comparative Phenological Studies of Trees in Tropical Wet and Dry Forests in the Lowlands of Costa Rica

Gordon W. Frankie, Herbert G. Baker and Paul A. Opler
Journal of Ecology
Vol. 62, No. 3 (Nov., 1974), pp. 881-919
DOI: 10.2307/2258961
Stable URL: http://www.jstor.org/stable/2258961
Page Count: 39
  • Read Online (Free)
  • Download ($18.00)
  • Subscribe ($19.50)
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Comparative Phenological Studies of Trees in Tropical Wet and Dry Forests in the Lowlands of Costa Rica
Preview not available

Abstract

During 1969-70, 185 tree species at a Wet forest site and 113 species at a Dry forest site in Costa Rica were systematically observed for changes in leafing, flowering and fruiting. (1) At the Wet forest site, the greatest amount of leaf fall in the overstorey and understorey trees occurred primarily during the first (more severe) dry season. At that time, 17% of the tree species from both storeys lost leaves. (2) At the Dry forest site, the period of greatest leaf fall coincided with the long dry period; at that time 75% of the species lost leaves. (3) Most Wet forest species flushed large quantities of new leaves during the first dry season. This was in contrast to the Dry forest site where most species flushed leaves at the onset of the first rainy season. (4) Two apparent flowering peaks in the overstorey tree species and three apparent flowering peaks in the understorey tree species were recorded during the year at the Wet forest site. These major flowering periods in both layers occurred during wet as well as dry seasons, and two of the peak periods of the overstorey appeared to be out of phase with two of the understorey. The species at the Wet forest site were well represented by both `seasonal' and `extended' flowering species. (5) At the Dry forest site, two peak periods of flowering activity were recognized. One extensive period occurred during the long dry season and a second peak period was recorded at the onset of the rainy season. Most species were of a `seasonal' rather than `extended' flowering nature. (6) With regard to Wet forest fruiting, substantial numbers of species (at least 37) from both storeys were in mature fruit during each month, but a peak in fruiting occurred in both layers during the second dry season (August-October); the fruiting peaks of the two storeys were separated by one month. The disseminules of most Wet forest species were not adapted for wind dispersal. (7) A peak period in the production of mature fruit occurred during the latter part of the long dry season at the Dry forest site. A significant proportion (31%) of the Dry forest species had disseminules adapted for wind dispersal. (8) When phenological patterns of vicarious species of the two forests were compared, only flowering patterns showed similarity (11/27 species). Leafing and fruiting patterns of vicarious species tended to follow the general trends of the respective forest ecosystems. (9) Periodicity patterns of most species in common between the two forest sites were similar. (10) The phenological patterns recorded are discussed in relation to climatic `triggers' (proximate factors) and plant-animal interactions (ultimate factors).

Page Thumbnails

  • Thumbnail: Page 
881
    881
  • Thumbnail: Page 
882
    882
  • Thumbnail: Page 
883
    883
  • Thumbnail: Page 
884
    884
  • Thumbnail: Page 
885
    885
  • Thumbnail: Page 
886
    886
  • Thumbnail: Page 
887
    887
  • Thumbnail: Page 
888
    888
  • Thumbnail: Page 
889
    889
  • Thumbnail: Page 
890
    890
  • Thumbnail: Page 
891
    891
  • Thumbnail: Page 
892
    892
  • Thumbnail: Page 
893
    893
  • Thumbnail: Page 
894
    894
  • Thumbnail: Page 
895
    895
  • Thumbnail: Page 
896
    896
  • Thumbnail: Page 
897
    897
  • Thumbnail: Page 
898
    898
  • Thumbnail: Page 
899
    899
  • Thumbnail: Page 
900
    900
  • Thumbnail: Page 
901
    901
  • Thumbnail: Page 
902
    902
  • Thumbnail: Page 
903
    903
  • Thumbnail: Page 
904
    904
  • Thumbnail: Page 
905
    905
  • Thumbnail: Page 
906
    906
  • Thumbnail: Page 
907
    907
  • Thumbnail: Page 
908
    908
  • Thumbnail: Page 
909
    909
  • Thumbnail: Page 
910
    910
  • Thumbnail: Page 
911
    911
  • Thumbnail: Page 
912
    912
  • Thumbnail: Page 
913
    913
  • Thumbnail: Page 
914
    914
  • Thumbnail: Page 
915
    915
  • Thumbnail: Page 
916
    916
  • Thumbnail: Page 
917
    917
  • Thumbnail: Page 
918
    918
  • Thumbnail: Page 
919
    919