Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8488361 | Agriculture, Ecosystems & Environment | 2011 | 11 Pages |
Abstract
It is a well-established concept that nitrogen (N) limits plant growth and ecosystem production. However, whether N limits land carbon (C) sequestration - particularly in soil, the largest pool in the land - remains highly controversial. We conducted a meta-analysis to synthesize 257 studies published in the literature with 512 paired comparisons to quantify the changes of ecosystem C processes in response to N addition. Our results show that N addition significantly increased aboveground, belowground, and litter C pools by 35.7, 23.0, and 20.9%, respectively, across all the studies. Despite the substantial increases in C inputs from vegetation to soil system, N addition resulted in no significant change in C storage of both organic horizon and mineral soil in forests and grasslands, but a significant 3.5% increase in agricultural ecosystems, largely due to less contribution from aboveground production and increases in DOC and soil respiration. Thus, N stimulation of C storage primarily occurred in plant pools but little in soil pools. Moreover, N-induced change in soil C storage was positively related to changes in belowground production but not to those in aboveground growth. Our global synthesis also suggests that earth system models need to treat soil C inputs from aboveground and belowground sources differentially for soil C sequestration in response to N deposition and fertilization.
Related Topics
Life Sciences
Agricultural and Biological Sciences
Agronomy and Crop Science
Authors
Meng Lu, Xuhui Zhou, Yiqi Luo, Yuanhe Yang, Changming Fang, Jiakuan Chen, Bo Li,