Research Article

Temporal Variation of N Isotopic Composition of Decomposing Legume Roots and Its Implications to N Cycling Estimates in Tracer Studies in Agroforestry Systems

Figure 3

Simulated change of plant 15N after input of 15N-labelled decomposing residue in the residue application (RA; a, c, e) and full interaction experiments (FI; b, d, f), when the residue is considered to consist of (a, b) a single fraction with uniform C : N and 15N, (c, d) two fractions with different C : N but uniform 15N, and (e, f) two fractions with different C : N and 15N. Simulations were conducted with proportionally equal N uptake from soil inorganic N sources (Sf = 0) and by optimising the N source factor in the simulations. Vertical bars indicate the standard error of mean for the observations ( and for the RA and FI experiments, resp.). For explanations and parameter values, see text and Table 2.
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