Potential of global cropland phytolith carbon sink from optimization of cropping system and fertilization

Zhaoliang Song; Jeffrey F Parr; Fengshan Guo

doi:10.1371/journal.pone.0073747

Potential of global cropland phytolith carbon sink from optimization of cropping system and fertilization

PLoS One. 2013 Sep 16;8(9):e73747. doi: 10.1371/journal.pone.0073747. eCollection 2013.

Authors

Zhaoliang Song¹, Jeffrey F Parr, Fengshan Guo

Affiliation

¹ Zhejiang Provincial Key Laboratory of C Cycling in Forest Ecosystems and C Sequestration, Zhejiang Agricultural and Forestry University, Lin'an, Zhejiang, China ; School of Environment and Resources, Zhejiang Agricultural and Forestry University, Lin'an, Zhejiang, China ; State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, Guizhou, China.

Abstract

The occlusion of carbon (C) by phytoliths, the recalcitrant silicified structures deposited within plant tissues, is an important persistent C sink mechanism for croplands and other grass-dominated ecosystems. By constructing a silica content-phytolith content transfer function and calculating the magnitude of phytolith C sink in global croplands with relevant crop production data, this study investigated the present and potential of phytolith C sinks in global croplands and its contribution to the cropland C balance to understand the cropland C cycle and enhance long-term C sequestration in croplands. Our results indicate that the phytolith sink annually sequesters 26.35 ± 10.22 Tg of carbon dioxide (CO2) and may contribute 40 ± 18% of the global net cropland soil C sink for 1961-2100. Rice (25%), wheat (19%) and maize (23%) are the dominant contributing crop species to this phytolith C sink. Continentally, the main contributors are Asia (49%), North America (17%) and Europe (16%). The sink has tripled since 1961, mainly due to fertilizer application and irrigation. Cropland phytolith C sinks may be further enhanced by adopting cropland management practices such as optimization of cropping system and fertilization.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Carbon Sequestration / physiology*
Crops, Agricultural / metabolism*
Environmental Monitoring
Fertilization*

Grants and funding

The authors are grateful for support from the National Natural Science Foundation of China (Grant No. 41103042), the Zhejiang Province Key Science and Technology Innovation Team (No. 2010R50030), and the Opening Project of State Key Laboratory of Environmental Geochemistry (SKLEG9011). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.