Does Elevated [CO] Only Increase Root Growth in the Topsoil? A FACE Study with Lentil in a Semi-Arid Environment.

Atmospheric carbon dioxide concentrations [CO] are increasing steadily. Some reports have shown that root growth in grain crops is mostly stimulated in the topsoil rather than evenly throughout the soil profile by e[CO], which is not optimal for crops grown in semi-arid environments with strong reliance on stored water. An experiment was conducted during the 2014 and 2015 growing seasons with two lentil () genotypes grown under Free Air CO Enrichment (FACE) in which root growth was observed non-destructively with mini-rhizotrons approximately every 2-3 weeks.

Assessing crop residue phosphorus speciation using chemical fractionation and solution 31P nuclear magnetic resonance spectroscopy.

At physiological maturity, nutrients in crop residues can be released to the soil where they are incorporated into different labile and non-labile pools while the remainder is retained within the residue itself. The chemical speciation of phosphorus (P) in crop residues is an important determinant of the fate of this P. In this study, we used chemical fractionation and (31)P nuclear magnetic resonance (NMR) spectroscopy, first separately and then together, to evaluate the P speciation of mature oat (Avena sativa) residue.