The effect of organic structures on the water stability of macro-aggregates.
| dc.contributor.author | Monreal, C.M. | |
| dc.contributor.author | Campbell, C.A. | |
| dc.contributor.author | Anderson, D.W. | |
| dc.contributor.author | Schnitzer, M. | |
| dc.date.accessioned | 2018-09-13T17:56:33Z | |
| dc.date.available | 2018-09-13T17:56:33Z | |
| dc.date.issued | 1993-02-25 | |
| dc.description.abstract | A study was conducted to identify the chemical structures of soil organic matter and examine their effect on the water stability of macro-aggregates (>250 um) in a SiL Brown Chernozem under wheat-fallow (WF) and continuous wheat (CW) . The proportion of water stable macro-aggregates were determined by wet sieving. Chemical structures of soil organic matter were characterized by pyrolysis field ionization mass spectrometry (Py-FIMS), and grouped into seven classes: carbohydrates, phenolic and lignin monomers, lignin dimers, lipids + alkanes and alkenes, sterols, alkyl aromatic and N-compounds. In comparison with CW, there was a reduction in the proportion of macro-aggregates and an increase of micro-aggregates in the WF crop rotation. Sixty-five percent of all the soil organic matter (SOM) was identified by Py-FIMS. The average concentration of each class of compound in whole soil and macro-aggregate samples ranged between 0.1 and 15% of the total identified SOM. Carbohydrates, phenolic, and lignin monomers were the most abundant compounds (>10%). Linear regression models (r2 ~ 0.96, p=0.05) showed that the stability of macro-aggregates was highly correlated with the concentration of the least abundant (<3. 5%) structures of sterols, lipids and lignin dimers. These compounds are metabolic products of plants and soil organisms. | en_US |
| dc.description.version | Non-Peer Reviewed | |
| dc.identifier.uri | http://hdl.handle.net/10388/10481 | |
| dc.language.iso | en | en_US |
| dc.relation.ispartof | Soils and Crops Workshop | |
| dc.rights | Attribution-NonCommercial-NoDerivs 2.5 Canada | * |
| dc.rights.uri | http://creativecommons.org/licenses/by-nc-nd/2.5/ca/ | * |
| dc.title | The effect of organic structures on the water stability of macro-aggregates. | en_US |
| dc.type | Presentation | en_US |