Ulster University Logo

Ulster Institutional Repository

Plant effects on soil N mineralization are mediated by the composition of multiple soil organic fractions

Biomedical Sciences Research Institute Computer Science Research Institute Environmental Sciences Research Institute Nanotechnology & Advanced Materials Research Institute

Fornara, D. A., Bardgett, R, Steinbeiss, S, Zak, D. R., Gleixner, G and Tilman, D (2010) Plant effects on soil N mineralization are mediated by the composition of multiple soil organic fractions. Ecological Research, DOI 10.1007/s11284-010-0777-0 . [Journal article]

[img]PDF
Indefinitely restricted to Repository staff only.

375Kb

URL: http://www.springerlink.com/content/t56055v0260x4198/

DOI: DOI 10.1007/s11284-010-0777-0

Abstract

Despite the topic of soil nitrogen (N) mineralization being well-studied, very few studies have addressed the relative contribution of different plant and soil variables in influencing soil N mineralization rates, and thus the supply of inorganic N to plants. Here, we used data from a well-studied N-limited grassland to address the relative effects of six plant and soil variables on net and on gross rates of soil N mineralization. We also addressed whether plant effects on soil N mineralization were mediated by changes in C and N concentrations of multiple soil organic matter (SOM) fractions. Regression analyses show that key plant traits (i.e., plant C:N ratios and total root mass) were more important than total C and N concentrations of bulk soil in influencing N mineralization. This was mainly because plant traits influenced the C and N concentration (and C:N ratios) of different SOM fractions, which in turn were significantly associated with changes in net and gross N mineralization. In particular, C:N ratios of a labile soil fraction were negatively related to net soil N mineralization rates, whereas total soil C and N concentrations of more recalcitrant fractions were positively related to gross N mineralization. Our study suggests that changes in belowground N-cycling can be better predicted by simultaneously addressing how plant C:N ratios and root mass affect the composition and distribution of different SOM pools in N-limited grassland systems.

Item Type:Journal article
Faculties and Schools:Faculty of Life and Health Sciences
Faculty of Life and Health Sciences > School of Environmental Sciences
Research Institutes and Groups:Environmental Sciences Research Institute
Environmental Sciences Research Institute > Terrestrial Ecology
ID Code:16417
Deposited By:Dr Dario Fornara
Deposited On:23 Nov 2010 15:26
Last Modified:23 Nov 2010 15:26

Repository Staff Only: item control page