Variability and controls of soil CO2fluxes under different tillage and crop residue managements in a wheat-maize double-cropping system

被引：2

作者：

Qiu, Qingyan ^{[1
]}

Wu, Lanfang ^{[2
]}

Hu, Yalin ^{[1
]}

Lai, Derrick Yuk Fo ^{[3
]}

Wang, Weiqi ^{[4
]}

Xu, Yanyan ^{[2
]}

Mgelwa, Abubakari Said ^{[1
,5
,6
]}

Li, Binbin ^{[2
]}

机构：

[1] Fujian Agr & Forestry Univ, Coll Forest, Forest Ecol Stable Isotope Ctr, Fuzhou 350002, Peoples R China

[2] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Yucheng Comprehens Expt Stn, 11A,Datun Rd, Beijing 100101, Peoples R China

[3] Chinese Univ Hong Kong, Dept Geog & Resource Management, Hong Kong, Peoples R China

[4] Fujian Normal Univ, Key Lab Humid Subtrop Ecogeog Proc, Minist Educ, Fuzhou 350007, Peoples R China

[5] Mwalimu Julius K Nyerere Univ Agr & Technol, Coll Nat Resources Management & Tourism, POB 976, Musoma, Tanzania

[6] Chinese Acad Sci, Inst Appl Ecol, Key Lab Forest Ecol & Management, Shenyang 110164, Liaoning, Peoples R China

来源：

ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH | 2020年 / 27卷 / 36期

关键词：

Soil CO(2)flux; Soil depth; Conventional tillage; No tillage; Crop residue application; CARBON-DIOXIDE EMISSIONS; DISSOLVED ORGANIC-CARBON; GREENHOUSE-GAS EMISSIONS; LONG-TERM TILLAGE; NO-TILLAGE; CO2; EMISSIONS; WINTER-WHEAT; CONSERVATION TILLAGE; SEASONAL-VARIATIONS; MICROBIAL BIOMASS;

D O I：

10.1007/s11356-020-10437-4

中图分类号：

X [环境科学、安全科学];

学科分类号：

08 ; 0830 ;

摘要：

The spatial and temporal variability of soil CO(2)emissions from agricultural soils is inherently high. While tillage and crop residue practices play vital roles in governing soil CO(2)emission, their effects on the variability of soil CO(2)fluxes across depths and seasons are still poorly understood. To address this, an experiment consisting of four treatments, namely conventional tillage with (CT+) and without crop residue application (CT-), as well as no tillage with (NT+) and without crop residue application (NT-), was conducted to investigate soil CO(2)fluxes at top 40 cm soils with 10-cm depth intervals in a winter wheat-summer maize rotation system in the North China Plain. Our results showed soil CO(2)fluxes increased with depth in both the wheat- and maize-growing seasons. However, the dominant factors in regulating soil CO(2)fluxes changed with soil depth and seasons. In the wheat-growing season, increase in soil CO(2)fluxes with depth was attributed to the increase of dissolved organic carbon-to-nitrogen ratio (DOC/DON) and a decline in soil DON concentration along the soil profile. These factors explained about 55-96% of the total variation in soil CO(2)fluxes at different soil depths. In the maize-growing season, the dominant factors were soil DOC/DON ratio, soil DON concentrations, and soil moisture. These factors explained approximately 79-96% of the total variation in soil CO(2)fluxes along the soil depth. Greater soil CO(2)fluxes (except at 30-40 cm depth) were observed in NT- than CT- treatments. Furthermore, crop residue application enhanced soil CO(2)fluxes across different depths, but the enhancement was more prominent in CT+ than NT+. Moreover, soil CO(2)fluxes in the maize-growing season were greater than those in the wheat-growing season. Our results demonstrate that the effects of tillage regimes and crop residue management practices on soil CO(2)emissions are not confined only to the plough layer but can extend to soils of over 30 cm depths. We also need to revisit the general conventional view that no tillage can significantly reduce soil CO(2)emissions compared with conventional tillage for better climate change mitigation.

引用

页码：45722 / 45736

页数：15

共 70 条

[1] No-tillage lessens soil CO2 emissions the most under arid and sandy soil conditions: results from a meta-analysis [J].