Carbon flow from C-labeled clover and ryegrass residues into a residue-associated microbial community under field conditions
نویسندگان
چکیده
Microbial colonization of soil-incorporated, C-labeled, crimson clover and ryegrass straw residues was followed under western Oregon field conditions from late summer (September) to the following early summer (mid-June) by measuring the C content of phospholipid fatty acid (PLFA) extracted from residues recovered from soil. Residue type influenced the rate of appearance of specific PLFA during early decomposition, with branch chain bacterial PLFA (i15:0, a15:0, i16:0) appearing on clover and ryegrass residues in October and November, respectively. By April, additional PLFA (16:1o5, 16:1o7, cy17:0, 18:0, 18:1o9) had appeared on both residues. Between April and June, microbial community structure shifted again with significant increases (cy17:0, 18:0, 18:1o9), and decreases (18:1o7+10Me18:0) detected in the quantities of specific PLFA on both residue types. In the case of clover, the PLFA-C was derived primarily from residue C (85–100%), whereas in the case of ryegrass, both residue C (57–66%), and soil C contributed substantially to the PLFA-C. r 2006 Elsevier Ltd. All rights reserved.
منابع مشابه
Carbon flow from C-labeled straw and root residues into the phospholipid fatty acids of a soil microbial community under field conditions
To better understand how residue quality and seasonal conditions influence the flow of C from both root and straw residues into the soil microbial community, we followed the incorporation of C-labeled crimson clover (Trifolium incarnatum) and ryegrass (Lolium multiflorum) root and straw residues into the phospholipid fatty acids (PLFA) of soil microbial biomass. After residue incorporation unde...
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