How Tillage and Fertilization Influence Soil N 2 O Emissions after Forestland Conversion to Cropland

Xiao Ren, Bo Zhu, Hamidou Bah and Syed Turab Raza
Additional contact information
Xiao Ren: Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China
Bo Zhu: Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China
Hamidou Bah: Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China
Syed Turab Raza: Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China

Sustainability, 2020, vol. 12, issue 19, 1-17

Abstract: Soil nitrous oxide (N 2 O) emissions are influenced by land use adjustment and management practices. To meet the increasing socioeconomic development and sustainable demands for food supply, forestland conversion to cropland occurs around the world. However, the effects of forestland conversion to cropland as well as of tillage and fertilization practices on soil N 2 O emissions are still not well understood, especially in subtropical regions. Therefore, field experiments were carried out to continuously monitor soil N 2 O emissions after the conversion of forestland to cropland in a subtropical region in Southwest China. One forestland site and four cropland sites were selected: forestland (CK), short-term croplands (tillage with and without fertilization, NC-TF and NC-T), and long-term croplands (tillage with and without fertilization, LC-TF and LC-T). The annual cumulative N 2 O flux was 0.21 kg N ha −1 yr −1 in forestland. After forestland conversion to cropland, the annual cumulative N 2 O flux significantly increased by 76‒491%. In the short-term and long-term croplands, tillage with fertilization induced cumulative soil N 2 O emissions that were 94% and 235% higher than those from tillage without fertilization. Fertilization contributed 63% and 84% to increased N 2 O emissions in the short-term and long-term croplands, respectively. A stepwise regression analysis showed that soil N 2 O emissions from croplands were mainly influenced by soil NO 3 − and NH 4 + availability and WFPS (water-filled pore space). Fertilization led to higher soil NH 4 + and NO 3 − concentrations, which thus resulted in larger N 2 O fluxes. Thus, to reduce soil N 2 O emissions and promote the sustainable development of the eco-environment, we recommend limiting the conversion of forestland to cropland, and meanwhile intensifying the shift from grain to green or applying advanced agricultural management practices as much as possible.

Keywords: land use change; tillage; fertilization; N 2 O fluxes; subtropical region (search for similar items in EconPapers)
JEL-codes: O13 Q Q0 Q2 Q3 Q5 Q56 (search for similar items in EconPapers)
Date: 2020
References: View references in EconPapers View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/2071-1050/12/19/7947/pdf (application/pdf)
https://www.mdpi.com/2071-1050/12/19/7947/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jsusta:v:12:y:2020:i:19:p:7947-:d:419612

Access Statistics for this article

Sustainability is currently edited by Ms. Alexandra Wu

More articles in Sustainability from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().