skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Effects of atmospheric CO/sub 2/ enrichment on the growth and mineral nutrition of Quercus alba seedlings in nutrient-poor soil

Journal Article · · Plant Physiol.; (United States)
OSTI ID:6896946

One-year-old dormant white oak (Quercus alba L.) seedlings were planted in a nutrient-deficient forest soil and grown for 40 weeks in growth chambers at ambient (362 microliters per liter) or elevated (690 microliters per liter) levels of CO/sub 2/. Although all of the seedlings became severely N deficient, CO/sub 2/ enrichment enhanced growth by 85%, with the greatest enhancement in root systems. The growth enhancement did not increase the total water use per plant, so water-use efficiency was significantly greater in elevated CO/sub 2/. Total uptake of N, S, and B was not affected by CO/sub 2/, therefore, tissue concentrations of these nutrients were significantly lower in elevated CO/sub 2/. An increase in nutrient-use efficiency with respect to N was apparent in that a greater proportion of the limited N pool in the CO/sub 2/-enriched plants was in fine roots and leaves. The uptake of other nutrients increased with CO/sub 2/ concentration, and P and K uptake increased in proportion to growth. Increased uptake of P by plants in elevated CO/sub 2/ may have been a result of greater proliferation of fine roots and associated mycorrhizae and rhizosphere bacteria stimulating P mineralization. The results demonstrate that a growth response to CO/sub 2/ enrichment is possible in nutrient-limited systems, and that the mechanisms of response may include either increased nutrient supply or decreased physiological demand. 30 references, 2 figures, 4 tables.

Research Organization:
Oak Ridge National Lab., TN
DOE Contract Number:
AC05-84OR21400
OSTI ID:
6896946
Journal Information:
Plant Physiol.; (United States), Vol. 82
Country of Publication:
United States
Language:
English