Premium
A branch bag and CO 2 control system for long‐term CO 2 enrichment of mature Sitka spruce [ Picea sitchensis (Bong.) Carr.]
Author(s) -
BARTON C. V. M.,
LEE H. S. J.,
JARVIS P. G.
Publication year - 1993
Publication title -
plant, cell and environment
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.646
H-Index - 200
eISSN - 1365-3040
pISSN - 0140-7791
DOI - 10.1111/j.1365-3040.1996.tb02072.x
Subject(s) - horticulture , photosynthesis , chemistry , stomatal conductance , botany , photosynthetically active radiation , picea abies , biology
This paper describes the construction and performance of branch bags and a CO 2 control system used to fumigate branches of mature Sitka spruce trees with air enriched in CO 2 (700 μmolmol ‐1 ). It contains some examples of results obtained using the system over the course of the first two growing seasons. The branch bags have run continuously for 2 years with very few problems. CO 2 concentrations were within 20 μmol mol ‐1 of the target concentration for more than 90% of the time. Temperatures within the bags were slightly higher than ambient (1–2 °C) and this had some effect on phenology. Attenuation of quantum flux density (photosynthetically active radiation) was 10–15%. The branch bag system has enabled investigation into the effects of elevated CO 2 on mature tissue without the problems and expense of fumigating whole trees. Growth in elevated CO 2 resulted in an increase in starch and a decrease in soluble protein content of needles. Stomatal conductance was higher in elevated CO 2 grown needles, and there was some evidence of an increase in photosynthetic capacity.