Variations in the profile distribution and protection mechanisms of organic carbon under long-term fertilization in a Chinese Mollisol

被引：67

作者：

Abrar, Muhammad Mohsin ^{[1
]}

Xu, Minggang ^{[1
]}

Shah, Syed Atizaz Ali ^{[1
]}

Aslam, Muhammad Wajahat ^{[2
]}

Aziz, Tariq ^{[3
,4
]}

Mustafa, Adnan ^{[1
]}

Ashraf, Muhammad Nadeem ^{[1
]}

Zhou, Baoku ^{[5
]}

Ma, Xingzhu ^{[5
]}

机构：

[1] Chinese Acad Agr Sci, Inst Agr Resources & Reg Planning, Natl Engn Lab Improving Qual Arable Land, Beijing 100081, Peoples R China

[2] Chinese Acad Sci, Inst Geochem, State Key Lab Environm Geochem, Guiyang 550081, Peoples R China

[3] Univ Agr Faisalabad, Inst Soil & Environm Sci, UAF Sub Campus Depalpur, Faisalabad 38040, Pakistan

[4] Univ Western Australia, Sch Agr & Environm, 35 Sterling Highway, Perth, WA, Australia

[5] Heilongjiang Acad Agr Sci, Inst Environm & Resources, Harbin 150086, Peoples R China

来源：

SCIENCE OF THE TOTAL ENVIRONMENT | 2020年 / 723卷

基金：

中国国家自然科学基金;

关键词：

Long-term fertilization; Organic carbon distribution; SOC fractionation; Stabilization mechanisms; Subsoil; Soil profile; PARTICLE-SIZE FRACTIONS; MAIZE CROPPING SYSTEM; MATTER FRACTIONS; MICROBIAL COMMUNITY; TEMPERATE SOILS; LAND-USE; SEQUESTRATION; MANAGEMENT; SATURATION; MANURE;

D O I：

10.1016/j.scitotenv.2020.138181

中图分类号：

X [环境科学、安全科学];

学科分类号：

08 ; 0830 ;

摘要：

Long term fertilization may have a significant effect on soil organic carbon (SOC) fractions and profile distribution. However, previous research mostly explored the SOC in the topsoil and provided little or no information about its distribution in deeper layers and various protection mechanisms particularly under long-term fertilization. The present study investigated the contents and profile distribution (0-100 cm) of distinct SOC protection mechanisms in the Mollisol (black soil) of Northeast China after 35 years of mineral and manure application. The initial Organic Matter content of the topsoil (0-20 cm) ranged from 26.4 to 27.0 g kg(-1) soil, and ploughing depth was up to 20 cm. A combination of physical-chemical fractionation methods was employed to study various SOC fractions. There were significant variations throughout the profile among the various fractions and protection mechanisms. In topsoil (to 40 cm), mineral plus manure fertilization (MNPK) increased the total SOC content and accounted for 16.15% in the 0-20 cm and 12.34% in the 20-40 cm layer, while the manure alone (M) increased the total SOC by 56.14%, 48.73% and 27.73% in the subsoil (40-60, 60-80 and 80-100 cm, respectively). Moreover, MNPK and M in the topsoil and subsoil, respectively increased the unprotected coarse particulate organic carbon (cPOC) (48% and 26%, respectively), physically protected micro-aggregate (mu agg) (20% and 18%, respectively) and occluded particulate organic carbon (iPOC) contents (279% and 93%, respectively) compared with the control (CK). A positive linear correlation was observed between total SOC and the cPOC, iPOC, physico-biochemically protected NH-mu Silt and physico-chemically protected H-mu Silt (p < 0.01) across the whole profile. Overall, physical, physico-biochemical and physico-chemical protection were the predominant mechanisms to sequester carbon in the whole profile, whereas the biochemical protection mechanisms were only relevant in the topsoil, thus demonstrating the differential mechanistic sensitivity of fractions for organic carbon cycling across the profile. (C) 2020 Elsevier B.V. All rights reserved.

引用

页数：13

共 82 条

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