The photosynthetic characteristics of saplings of eight canopy tree species in a disturbed neotropical rain forest

Title:

The photosynthetic characteristics of saplings of eight canopy tree species in a disturbed neotropical rain forest

Creator:

Vera, N. E., Finegan, B., and Newton, A. C.

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:8975cc0b-3320-4cf1-9b84-130053639080
uuid:8975cc0b-3320-4cf1-9b84-130053639080
issn:0300-3604
doi:10.1023/A:1007076103204

Subject:

Costa Rica, guilds, hemispherical photograph, logging, modelling, silviculture, and sustainable management

Type:

model:article and TEXT

Format:

bez média and svazek

Description:

Foliar gas exchange characteristics, understorey microclimate, and crown irradiation were assessed for saplings of eight canopy tree species in two plots of neotropical rain forest with different degrees of canopy opening. Species studied belonged to different putative guilds: shade intolerants (both short-lived--pioneers--and long-lived), intermediates, and shade-tolerants. A considerable overlap was recorded between species in values of the photosynthetic rate per unit leaf area (PN). The highest median PN (1.26 µmol m-2 s-1) was recorded in the pioneer Croton killipianus, while slightly lower median values were recorded in Simarouba amara and Pentaclethra macroloba, and markedly lower values in two species of Vochysiaceae (Qualea paraense and Vochysia ferruginea), both putative intolerants. Highest median stomatal conductance (gs) was also shown by C. killipianus, while S. amara, P. macroloba, and L. procera exhibited intermediate values, and the lowest gs was shown by V. ferruginea and Q. paraense. Overall irradiance and crown irradiation, PN, and gs of saplings were higher in the plot which had previously received a silvicultural treatment. Most values of photosynthetic photon flux density (PPFD) were <100 µmol m-2 s-1 in both plots, with shortlived peaks of up to 2000 µmol m-2 s-1 in the treated plot. When the relationship between PN and irradiance (I) was examined by fitting PN/I curves, the degree of fit varied markedly between species, values of the regression coefficient r2 were between 0.09 and 0.51. No significant differences between species were recorded in Pmax and species also demonstrated little variation in the predicted values of dark respiration (RD), values varying between -0.51 and -1.46 µmol m-2 s-1 in Q. paraense and Minquartia guianensis, respectively. Fitted values of apparent quantum efficiency were also fairly uniform, generally falling within the range 0.02-0.03 mol(CO2) mol-1(photon). and N. E. Vera, B. Finegan, A. C. Newton.

Language:

Multiple languages

Rights:

http://creativecommons.org/licenses/by-nc-sa/4.0/
policy:public

Coverage:

407-422

Source:

Photosynthetica | 1999 Volume:36 | Number:3

Harvested from:

CDK

Metadata only:

false