Modelling the effects of moisture on barley straw and root decomposition in the field

Olof Andrén, Eliel steen, K. Rajkai

Research output: Contribution to journalArticle

45 Citations (Scopus)

Abstract

In a field experiment with barley on a clay soil, four treatments were compared: the control (C) was not nitrogen fertilized or irrigated; drought treatment (D) was identical to C, except that screens had been installed to divert rainwater; irrigation (I) and irrigation-fertilization (IF) treatments were irrigated using a drip-tube system, with liquid fertilizer (260kg N ha-1yr-1) applied daily in IF according to predicted plant uptake. Litter-bags with barley straw were buried in all treatments at 10 cm depth on 19 May 1988 and sampled five times during the growing season. Decomposition rates were calculated assuming exponential decay. The rates were highly dependent on soil moisture, and the constants ranged from 0.54% day-1 in D to 0.92% day-1 in IF. A simulation model with driving variables based on Q10 temperature dependence and a log-linear relationship between soil water tension and activity was fitted to the same data set. The rate constants became quite similar between the four treatments, ranging from 1.1 to 1.3% optimum day-1. Thus it was concluded that the assumptions and parameters used for temperature and moisture dependence were valid. Roots collected from each of the four treatments on four occasions were put in litter-bags, buried in the soil and taken up after about 20 days. Observed root decomposition rates were lowest in D. The rates for all treatments were highest early in the growing season and decreased thereafter. When temperature and moisture effects were compensated for using the climatic correction factors for barley straw, the decreasing trend remained, which was attributed to reduced decomposability of the roots during the growing season. The results indicate that using a constant value for root decomposability when calculating root turnover can give misleading results.

Original languageEnglish
Pages (from-to)727-736
Number of pages10
JournalSoil Biology and Biochemistry
Volume24
Issue number8
DOIs
Publication statusPublished - 1992

Fingerprint

barley straw
Straw
Hordeum
Irrigation
barley
straw
Moisture
Soil
Fertilization
moisture
irrigation
decomposition
Decomposition
degradation
growing season
Soils
modeling
Temperature
bags
liquid fertilizers

ASJC Scopus subject areas

  • Soil Science
  • Biochemistry
  • Ecology
  • Earth and Planetary Sciences(all)
  • Environmental Science(all)

Cite this

Modelling the effects of moisture on barley straw and root decomposition in the field. / Andrén, Olof; steen, Eliel; Rajkai, K.

In: Soil Biology and Biochemistry, Vol. 24, No. 8, 1992, p. 727-736.

Research output: Contribution to journalArticle

@article{dd97edc7204e45b2aff2968e5dc9bd23,
title = "Modelling the effects of moisture on barley straw and root decomposition in the field",
abstract = "In a field experiment with barley on a clay soil, four treatments were compared: the control (C) was not nitrogen fertilized or irrigated; drought treatment (D) was identical to C, except that screens had been installed to divert rainwater; irrigation (I) and irrigation-fertilization (IF) treatments were irrigated using a drip-tube system, with liquid fertilizer (260kg N ha-1yr-1) applied daily in IF according to predicted plant uptake. Litter-bags with barley straw were buried in all treatments at 10 cm depth on 19 May 1988 and sampled five times during the growing season. Decomposition rates were calculated assuming exponential decay. The rates were highly dependent on soil moisture, and the constants ranged from 0.54{\%} day-1 in D to 0.92{\%} day-1 in IF. A simulation model with driving variables based on Q10 temperature dependence and a log-linear relationship between soil water tension and activity was fitted to the same data set. The rate constants became quite similar between the four treatments, ranging from 1.1 to 1.3{\%} optimum day-1. Thus it was concluded that the assumptions and parameters used for temperature and moisture dependence were valid. Roots collected from each of the four treatments on four occasions were put in litter-bags, buried in the soil and taken up after about 20 days. Observed root decomposition rates were lowest in D. The rates for all treatments were highest early in the growing season and decreased thereafter. When temperature and moisture effects were compensated for using the climatic correction factors for barley straw, the decreasing trend remained, which was attributed to reduced decomposability of the roots during the growing season. The results indicate that using a constant value for root decomposability when calculating root turnover can give misleading results.",
author = "Olof Andr{\'e}n and Eliel steen and K. Rajkai",
year = "1992",
doi = "10.1016/0038-0717(92)90246-T",
language = "English",
volume = "24",
pages = "727--736",
journal = "Soil Biology and Biochemistry",
issn = "0038-0717",
publisher = "Elsevier Limited",
number = "8",

}

TY - JOUR

T1 - Modelling the effects of moisture on barley straw and root decomposition in the field

AU - Andrén, Olof

AU - steen, Eliel

AU - Rajkai, K.

PY - 1992

Y1 - 1992

N2 - In a field experiment with barley on a clay soil, four treatments were compared: the control (C) was not nitrogen fertilized or irrigated; drought treatment (D) was identical to C, except that screens had been installed to divert rainwater; irrigation (I) and irrigation-fertilization (IF) treatments were irrigated using a drip-tube system, with liquid fertilizer (260kg N ha-1yr-1) applied daily in IF according to predicted plant uptake. Litter-bags with barley straw were buried in all treatments at 10 cm depth on 19 May 1988 and sampled five times during the growing season. Decomposition rates were calculated assuming exponential decay. The rates were highly dependent on soil moisture, and the constants ranged from 0.54% day-1 in D to 0.92% day-1 in IF. A simulation model with driving variables based on Q10 temperature dependence and a log-linear relationship between soil water tension and activity was fitted to the same data set. The rate constants became quite similar between the four treatments, ranging from 1.1 to 1.3% optimum day-1. Thus it was concluded that the assumptions and parameters used for temperature and moisture dependence were valid. Roots collected from each of the four treatments on four occasions were put in litter-bags, buried in the soil and taken up after about 20 days. Observed root decomposition rates were lowest in D. The rates for all treatments were highest early in the growing season and decreased thereafter. When temperature and moisture effects were compensated for using the climatic correction factors for barley straw, the decreasing trend remained, which was attributed to reduced decomposability of the roots during the growing season. The results indicate that using a constant value for root decomposability when calculating root turnover can give misleading results.

AB - In a field experiment with barley on a clay soil, four treatments were compared: the control (C) was not nitrogen fertilized or irrigated; drought treatment (D) was identical to C, except that screens had been installed to divert rainwater; irrigation (I) and irrigation-fertilization (IF) treatments were irrigated using a drip-tube system, with liquid fertilizer (260kg N ha-1yr-1) applied daily in IF according to predicted plant uptake. Litter-bags with barley straw were buried in all treatments at 10 cm depth on 19 May 1988 and sampled five times during the growing season. Decomposition rates were calculated assuming exponential decay. The rates were highly dependent on soil moisture, and the constants ranged from 0.54% day-1 in D to 0.92% day-1 in IF. A simulation model with driving variables based on Q10 temperature dependence and a log-linear relationship between soil water tension and activity was fitted to the same data set. The rate constants became quite similar between the four treatments, ranging from 1.1 to 1.3% optimum day-1. Thus it was concluded that the assumptions and parameters used for temperature and moisture dependence were valid. Roots collected from each of the four treatments on four occasions were put in litter-bags, buried in the soil and taken up after about 20 days. Observed root decomposition rates were lowest in D. The rates for all treatments were highest early in the growing season and decreased thereafter. When temperature and moisture effects were compensated for using the climatic correction factors for barley straw, the decreasing trend remained, which was attributed to reduced decomposability of the roots during the growing season. The results indicate that using a constant value for root decomposability when calculating root turnover can give misleading results.

UR - http://www.scopus.com/inward/record.url?scp=0027061168&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0027061168&partnerID=8YFLogxK

U2 - 10.1016/0038-0717(92)90246-T

DO - 10.1016/0038-0717(92)90246-T

M3 - Article

AN - SCOPUS:0027061168

VL - 24

SP - 727

EP - 736

JO - Soil Biology and Biochemistry

JF - Soil Biology and Biochemistry

SN - 0038-0717

IS - 8

ER -