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Title: The Jasper Ridge elevated CO{sub 2} experiment: Root acid phosphatase activity in Bromus hordeaceus and Avena barbata remains unchanged under elevated [CO{sub 2}]

Abstract

Root acid phosphatase activity increases phosphate available to plants by cleaving phosphate esters in soil organic matter. Because of increased plant growth potential under elevated [CO{sub 2}], we hypothesized that high [CO{sub 2}]-grown plants might exhibit higher phosphatase activity than low [CO{sub 2}]-grown plants. We assayed phosphatase activity in two species grown on two substrates (Bromus on serpentine soil and Bromus and Avena on sandstone soil) under high and low [CO{sub 2}] and under several nutrient treatments. Phosphatase activity was expressed per gram fresh weight of roots. Phosphatase activity of Bromus roots (on sandstone) was first assayed in treatments where only P and K, or only N, were added to soil. Bromus roots in this case showed strong induction of phosphatase activity when N only had been added to soil, indicating that Bromus regulated its phosphatase activity in response to phosphate availability. Both Bromus and Avena growing in sandstone, and Bromus growing in serpentine, showed enhanced phosphatase activity at high nutrient (N, P, and K) levels over that at low nutrient levels, but no differences between phosphatase activity were apparent between [CO{sub 2}] treatments. The increased phosphatase activity at high N, P, and K may indicate enhanced {open_quotes}growth demand{close_quotes} (reflectedmore » in higher biomass) in both Avena and Bromus. In contrast, though Bromus {open_quotes}growth demand{close_quotes} (biomass) increased under high [CO{sub 2}] on sandstone, phosphatase activity did not increase.« less

Authors:
 [1];  [2]
  1. Univ. of California, Berkeley, CA (United States)
  2. Stanford Univ., CA (United States)
Publication Date:
OSTI Identifier:
95760
Report Number(s):
CONF-9507129-
Journal ID: BECLAG; ISSN 0012-9623; TRN: 95:004728-0025
Resource Type:
Journal Article
Resource Relation:
Journal Name: Bulletin of the Ecological Society of America; Journal Volume: 76; Journal Issue: 2; Conference: 80. anniversary of the transdisciplinary nature of ecology, Snowbird, UT (United States), 30 Jul - 3 Aug 1995; Other Information: PBD: Jun 1995
Country of Publication:
United States
Language:
English
Subject:
56 BIOLOGY AND MEDICINE, APPLIED STUDIES; 55 BIOLOGY AND MEDICINE, BASIC STUDIES; 54 ENVIRONMENTAL SCIENCES; ACID PHOSPHATASE; ENZYME ACTIVITY; PLANT GROWTH; COMPARATIVE EVALUATIONS; CARBON DIOXIDE; BIOLOGICAL EFFECTS; ECOLOGICAL CONCENTRATION; ROOTS; CLIMATIC CHANGE

Citation Formats

Cardon, Z.G., and Jackson, R. The Jasper Ridge elevated CO{sub 2} experiment: Root acid phosphatase activity in Bromus hordeaceus and Avena barbata remains unchanged under elevated [CO{sub 2}]. United States: N. p., 1995. Web.
Cardon, Z.G., & Jackson, R. The Jasper Ridge elevated CO{sub 2} experiment: Root acid phosphatase activity in Bromus hordeaceus and Avena barbata remains unchanged under elevated [CO{sub 2}]. United States.
Cardon, Z.G., and Jackson, R. 1995. "The Jasper Ridge elevated CO{sub 2} experiment: Root acid phosphatase activity in Bromus hordeaceus and Avena barbata remains unchanged under elevated [CO{sub 2}]". United States. doi:.
@article{osti_95760,
title = {The Jasper Ridge elevated CO{sub 2} experiment: Root acid phosphatase activity in Bromus hordeaceus and Avena barbata remains unchanged under elevated [CO{sub 2}]},
author = {Cardon, Z.G. and Jackson, R.},
abstractNote = {Root acid phosphatase activity increases phosphate available to plants by cleaving phosphate esters in soil organic matter. Because of increased plant growth potential under elevated [CO{sub 2}], we hypothesized that high [CO{sub 2}]-grown plants might exhibit higher phosphatase activity than low [CO{sub 2}]-grown plants. We assayed phosphatase activity in two species grown on two substrates (Bromus on serpentine soil and Bromus and Avena on sandstone soil) under high and low [CO{sub 2}] and under several nutrient treatments. Phosphatase activity was expressed per gram fresh weight of roots. Phosphatase activity of Bromus roots (on sandstone) was first assayed in treatments where only P and K, or only N, were added to soil. Bromus roots in this case showed strong induction of phosphatase activity when N only had been added to soil, indicating that Bromus regulated its phosphatase activity in response to phosphate availability. Both Bromus and Avena growing in sandstone, and Bromus growing in serpentine, showed enhanced phosphatase activity at high nutrient (N, P, and K) levels over that at low nutrient levels, but no differences between phosphatase activity were apparent between [CO{sub 2}] treatments. The increased phosphatase activity at high N, P, and K may indicate enhanced {open_quotes}growth demand{close_quotes} (reflected in higher biomass) in both Avena and Bromus. In contrast, though Bromus {open_quotes}growth demand{close_quotes} (biomass) increased under high [CO{sub 2}] on sandstone, phosphatase activity did not increase.},
doi = {},
journal = {Bulletin of the Ecological Society of America},
number = 2,
volume = 76,
place = {United States},
year = 1995,
month = 6
}
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