Navigation Links
Soil's carbon storage capacity investigated

Madison, WI July 28, 2008--As atmospheric CO2 levels rise, methods to mitigate these increases are becoming very important. Three studies published in the July-August 2008 issue of Soil Science Society of America Journal explore the potential roles of soils as a C sink in different regions in the Western Hemisphere. Scientists from Alberta Agriculture and Rural Development (Canada), the National Institute of Agricultural Technology, the University of Buenos Aires (Argentina), and University of California, Davis (USA) have investigated soil C balance in distinct agroecosystems under different management practices including soil tillage, N fertilization, elimination of fallow, and establishment of grass. In each case, C sequestration occurred in response to higher C input to soil; however, increase in SOC was confined to labile fractions such as the light fraction and larger soil aggregates.

Investigation: Canada

In southeastern Alberta, a long-term study showed previously that eliminating summer fallow or establishing grass significantly increased soil organic C after 6 yr. In the 12th year of the study, total organic C and light fraction C were determined in three rotations with summer fallow, two continuously cropped rotations and grass. All rotations had subtreatments with different levels of fertilization. The light fraction of soil C was obtained using density separation and consisted mostly of non-decomposed root and straw fragments.

Although soil organic C was increased by elimination of summer fallow, fertilization, and establishment of grass, gains in soil organic C between Years 6 and 12 were negligible in all treatments except the fertilized grass treatment. Most of the gains in total soil organic C were due to increased light fraction C. The results indicate that much of the gain in soil organic C in response to improved practices on semiarid prairie soils likely occurs within one decade.

The full article is available for no charge for 30 days following the date of this summary. View the abstract at:

Investigation: Argentina

In the semiarid portion of the Pampas, scientist compared no-till management to a conventional tillage system (disk-tillage). Emissions of CO2-C from the soil and crop C inputs were determined, estimating soil C balance under both tillage systems.

As a part of this study, a field experiment was performed during 6 yr on an Entic Haplustoll where no-till and disk-tillage was applied to a soil cropped under a common rotation in the region (oat + hairy vetch, corn, wheat, oat). From Year 3 to 6 in situ CO2-C fluxes were measured and C inputs from above and below ground plant residues were estimated.

Results showed that in the semiarid environment of the study C sequestration occurred under no-till. The sequestration process was attributed to the effect of tillage systems on crop productivity rather than on the mineralization intensity of soil organic pools.

The full article is available for no charge for 30 days following the date of this summary. View the abstract at:

Investigation: United States

In Kentucky (USA) a study was conducted in a corn agroecosystem experiment to test the soil C saturation concept which postulates that there is an upper limit to the equilibrium soil C level of mineral soils even when soil C input is increased. In this experiment, a gradient of soil C input was produced with four N fertilizer application rates under two tillage systems, no-till and moldboard plowing. To investigate if physical protection of organic C leads to soil C saturation, C stabilization in soil fractions that differ in C stabilization potential was determined, and the relationship between soil C input and soil organic C was analyzed.

Total soil organic C was positively related to C input, and this was primarily due to C stabilization in larger soil aggregates. In both tillage systems, however, C in the two smallest soil size fractions did not increase with greater C input. Moreover, in three soil fractions further separated from larger soil aggregates, C associated with particulate organic matter and microaggregates increased with C input, but there was no increase in C associated with silt-plus-clay, which was the smallest soil size fraction.

Haegeun Chung at University of California, Davis, the first author of the study conducted in Kentucky (USA), stated "Our results indicate that soil fractions with low C stabilization potential show C saturation. Therefore, we need to consider soil C saturation levels to better predict the change in C sink capacity and fertility of soils when soil C input increases under higher plant production or organic amendment."

The full article is available for no charge for 30 days following the date of this summary. View the abstract at


Contact: Sara Uttech
Soil Science Society of America

Related biology news :

1. Experts to provide peek of Smithsonian soils exhibit
2. Senate resolution shines spotlight on the importance of soils
3. Reforestation using exotic plants can disturb the fertility of tropical soils
4. Specially-designed soils could help combat climate change
5. Compost can turn agricultural soils into a carbon sink, thus protecting against climate change
6. Tropical soils impede landmine detection
7. Earths soils bear unmistakable footprints of humans
8. Alliance for a Green Revolution in Africa commits 180M to revive farmers depleted soils
9. New insights into the fate of antiparasitics in manure and manured soils
10. Chemical compound present in detergents produce bacteria alterations in agricultural soils
11. CU researcher engineers sorghum that grows in poisonous soils
Post Your Comments:
(Date:11/12/2015)...   Growing need for low-cost, easy to ... paving the way for use of biochemical sensors ... in clinical, agricultural, environmental, food and defense applications. ... medical applications, however, their adoption is increasing in ... emphasis on improving product quality and growing need ...
(Date:11/9/2015)... 9, 2015  Synaptics Inc. (NASDAQ: SYNA ), ... broader entry into the automotive market with a comprehensive ... pace of consumer electronics human interface innovation. Synaptics, industry-leading ... for the automotive industry and will be implemented in ... Europe , Japan , and ...
(Date:10/29/2015)... , Oct. 29, 2015 Daon, a ... that it has released a new version of its ... in North America have already ... v4.0 also includes a FIDO UAF certified server ... already preparing to activate FIDO features. These customers include ...
Breaking Biology News(10 mins):
(Date:11/24/2015)... ... November 24, 2015 , ... This fall, global software solutions leader ... five states to develop and pitch their BIG ideas to improve health and wellness ... competing for votes to win the title of SAP's Teen Innovator, an all-expenses paid ...
(Date:11/24/2015)... , Nov. 24, 2015 /PRNewswire/ - Aeterna Zentaris ... today that the remaining 11,000 post-share consolidation (or ... Warrants (the "Series B Warrants") subject to the ... on November 23, 2015, which will result in ... giving effect to the issuance of such shares, ...
(Date:11/24/2015)... /CNW Telbec/ - ProMetic Life Sciences Inc. (TSX: PLI) (OTCQX: ... Pierre Laurin , President and Chief Executive Officer of ProMetic, ... Jaffray 27 th Annual Healthcare Conference to be held ... st , at 8.50am (ET) and ProMetic,s ... day. The presentation will be available live via a webcast ...
(Date:11/24/2015)... ... ... Whitehouse Laboratories is pleased to announce that it has completed construction on ... to basic USP 61, USP 62 and USP 51 testing specific to raw materials ... micro testing performed by one supplier. Management has formally announced that the ...
Breaking Biology Technology: