Management of irrigated agriculture to increase organic carbon storage in soils

Manejo de la Agricultura de irrigación para Incrementar el Almacenaje de Carbono Orgánico en los Suelos

Entry, James A. and Sojka, R.E. and Shewmaker, Glenn E. (2002) Management of irrigated agriculture to increase organic carbon storage in soils. Soil Science Society of America Journal. 66:1957-1964.

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Abstract

Increasing the amount of C in soils may be one method to reduce
the concentration of CO2 in the atmosphere. We measured organic
C stored in southern Idaho soils having long term cropping histories
that supported native sagebrush vegetation (NSB), irrigated moldboard
plowed crops (IMP), irrigated conservation-chisel-tilled crops
(ICT), and irrigated pasture systems (IP). The CO2 emitted as a result
of fertilizer production, farm operations, and CO 2 lost via dissolved
carbonate in irrigation water, over a 30-yr period, was included. Net
organic C in ecosystems decreased in the order IP > ICT > NSB >
IMP. In this study, if NSB were converted to IMP, 0.15 g C m- 2
would be emitted to the atmosphere, but if converted to IP 3.56 g C
m 2 could be sequestered. If IMP land were converted to ICT, 0.95 g
C m 2 could be sequestered in soil and if converted to IP 3.71 g C
m 2 could be sequestered. There are 2.6 x 108 ha of land worldwide
presently irrigated. If irrigated agriculture were expanded 10% and
the same amount of rainfed land were converted back to native grassland,
an increase of 3.4 x 109 Mg C (5.9% of the total C emitted in
the next 30 yr) could potentially be sequestered. The total projected
release of CO2 is 5.7 X 10'" Mg C worldwide during the next 30
yr. Converting rainfed agriculture back to native vegetation while
modestly increasing areas in irrigated agriculture could have a significant
impact on CO2 atmospheric concentrations while maintaining or
increasing food production.

Item Type:	Article
NWISRL Publication Number:	1085
Subjects:	Soil > Chemistry Mass Import - autoclassified (may be erroneous)
Depositing User:	Dan Stieneke
Date Deposited:	20 Nov 2010 21:50
Last Modified:	09 Nov 2016 18:27
Item ID:	144
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/144