1
|
Fang L, Deng Y, Lakshmanan P, Liu W, Tang X, Zou W, Zhang T, Wang X, Xiao R, Zhang J, Chen X, Su X. Selective increase of antibiotic-resistant denitrifiers drives N 2O production in ciprofloxacin-contaminated soils. JOURNAL OF HAZARDOUS MATERIALS 2024; 479:135673. [PMID: 39217949 DOI: 10.1016/j.jhazmat.2024.135673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Revised: 08/02/2024] [Accepted: 08/26/2024] [Indexed: 09/04/2024]
Abstract
Agricultural systems significantly contribute to global N2O emissions, which is intensified by excessive fertilization and antibiotic residues, attracting global concerns. However, the dynamics and pathways of antibiotics-induced soil N2O production coupled with microbial metabolism remain controversial. Here, we explored the pathways of N2O production in agricultural soils exposed to ciprofloxacin (CIP), and revealed the underlying mechanisms of CIP degradation and the associated microbial metabolisms using 15N-isotope labeling and molecular techniques. CIP exposure significantly increases the total soil N2O production rate. This is attributed to an unexpected shift from heterotrophic and autotrophic nitrification to denitrification and an increased abundance of denitrifiers Methylobacillus members under CIP exposure. The most striking strain M. flagellatus KT is further discovered to harbor N2O-producing genes but lacks a N2O-reducing gene, thereby stimulating denitrification-based N2O production. Moreover, this denitrifying strain is probably capable of utilizing the byproducts of CIP as carbon sources, evidenced by genes associated with CIP resistance and degradation. Molecular docking further shows that CIP is well ordered in the catalytic active site of CotA laccase, thus affirming the potential for this strain to degrade CIP. These findings advance the mechanistic insights into N2O production within terrestrial ecosystems coupled with the organic contaminants degradation.
Collapse
Affiliation(s)
- Linfa Fang
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400715, China
| | - Yue Deng
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400715, China
| | - Prakash Lakshmanan
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400715, China; Guangxi Key Laboratory of Sugarcane Genetic Improvement, Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences, Nanning 530007, China; Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture and Rural Affairs, Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences, Nanning 530007, China; Queensland Alliance for Agriculture and Food Innovation, University of Queensland, St Lucia, QLD 4067, Australia
| | - Weibing Liu
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400715, China
| | - Xiufeng Tang
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, Shanghai, China
| | - Wenxin Zou
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400715, China
| | - Tong Zhang
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400715, China
| | - Xiaozhong Wang
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400715, China
| | - Ran Xiao
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400715, China
| | - Jinbo Zhang
- School of Geography, Nanjing Normal University, Nanjing 210023, China; Liebig Centre for Agroecology and Climate Impact Research, Justus Liebig University, Germany
| | - Xinping Chen
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400715, China; Key Laboratory of Low-carbon Green Agriculture in Southwestern China, Ministry of Agriculture and Rural Affairs, Chongqing 400715, China
| | - Xiaoxuan Su
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400715, China.
| |
Collapse
|
2
|
Han B, Yao Y, Liu B, Wang Y, Su X, Ma L, Liu D, Niu S, Chen X, Li Z. Relative importance between nitrification and denitrification to N 2 O from a global perspective. GLOBAL CHANGE BIOLOGY 2024; 30:e17082. [PMID: 38273569 DOI: 10.1111/gcb.17082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 11/19/2023] [Accepted: 11/21/2023] [Indexed: 01/27/2024]
Abstract
Nitrous oxide (N2 O) is a potent greenhouse gas, and its mitigation is a pressing task in the coming decade. However, it remains unclear which specific process between concurrent nitrification and denitrification dominates worldwide N2 O emission. We snagged an opportunity to ascertain whence the N2 O came and which were the controlling factors on the basis of 1315 soil N2 O observations from 74 peer-reviewed articles. The average N2 O emission derived from nitrification (N2 On ) was higher than that from denitrification (N2 Od ) worldwide. The ratios of nitrification-derived N2 O to denitrification-derived N2 O, hereof N2 On :N2 Od , exhibited large variations across terrestrial ecosystems. Although soil carbon and nitrogen content, pH, moisture, and clay content accounted for a part of the geographical variations in the N2 On :N2 Od ratio, ammonia-oxidizing microorganisms (AOM):denitrifier ratio was the pivotal driver for the N2 On :N2 Od ratios, since the AOM:denitrfier ratio accounted for 53.7% of geographical variations in N2 On :N2 Od ratios. Compared with natural ecosystems, soil pH exerted a more remarkable role to dictate the N2 On :N2 Od ratio in croplands. This study emphasizes the vital role of functional soil microorganisms in geographical variations of N2 On :N2 Od ratio and lays the foundation for the incorporation of soil AOM:denitrfier ratio into models to better predict N2 On :N2 Od ratio. Identifying soil N2 O derivation will provide a global potential benchmark for N2 O mitigation by manipulating the nitrification or denitrification.
Collapse
Affiliation(s)
- Bingbing Han
- Key Laboratory of Low-Carbon Green Agriculture, Ministry of Agriculture and Rural Affairs, Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, and Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Yanzhong Yao
- Key Laboratory of Low-Carbon Green Agriculture, Ministry of Agriculture and Rural Affairs, Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, and Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Bin Liu
- Key Laboratory of Low-Carbon Green Agriculture, Ministry of Agriculture and Rural Affairs, Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, and Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Yini Wang
- Key Laboratory of Low-Carbon Green Agriculture, Ministry of Agriculture and Rural Affairs, Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, and Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Xiaoxuan Su
- Key Laboratory of Low-Carbon Green Agriculture, Ministry of Agriculture and Rural Affairs, Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, and Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Lihua Ma
- Key Laboratory of Low-Carbon Green Agriculture, Ministry of Agriculture and Rural Affairs, Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, and Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Dunyi Liu
- Key Laboratory of Low-Carbon Green Agriculture, Ministry of Agriculture and Rural Affairs, Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, and Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Shuli Niu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Xinping Chen
- Key Laboratory of Low-Carbon Green Agriculture, Ministry of Agriculture and Rural Affairs, Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, and Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Zhaolei Li
- Key Laboratory of Low-Carbon Green Agriculture, Ministry of Agriculture and Rural Affairs, Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, and Academy of Agricultural Sciences, Southwest University, Chongqing, China
| |
Collapse
|
3
|
Zheng J, Sakata T, Fujii K. Deciphering nitrous oxide emissions from tropical soils of different land uses. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 862:160916. [PMID: 36526175 DOI: 10.1016/j.scitotenv.2022.160916] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 12/08/2022] [Accepted: 12/09/2022] [Indexed: 06/17/2023]
Abstract
Tropical regions are hotspots of increasing greenhouse gas emissions associated with land-use change. Although many field studies have quantified soil fluxes of nitrous oxide (N2O; a potent greenhouse gas) from various land uses, the driving mechanisms remain uncertain. Here, we used tropical soils of diverse land uses and actively manipulated the soil moisture (35%, 60%, and 95% water-filled pore space [WFPS]) and substrate supply (control, nitrate, and nitrate plus glucose) to investigate the responses of N2O emissions with short-term incubations. We then identified key factors regulating N2O emissions out of a series of soil physicochemical and biological factors and explored how these factors interacted to drive N2O emissions. Land-use changes from primary forest to oil palm or Acacia plantation risks emitting more N2O, whereas low emissions could be maintained by conversion to Macaranga forest or Imperata grassland; these laboratory observations were corroborated by a literature synthesis of field N2O measurements across tropical regions. Soil redox potential (Eh) and labile organic nitrogen (LON; amino acid mixture, arginine, and urea) mineralization were among the factors with greatest influence on N2O emissions. In contrast to common understandings, the control of WFPS over N2O emissions was largely indirect, and acted through Eh. The mineralization of LON, particularly arginine, potentially played multiple roles in N2O production (e.g., bottlenecks of nitrifier-denitrification or simultaneous nitrification-denitrification versus substrate competition for co-denitrification). Structural equation models suggest that soil-environmental factors of different levels (from distal including land use, soil moisture, and pH to proximal such as LON mineralization) drive N2O emissions through cascading interactions. Overall, we show that, despite identical initial soil conditions, land conversion can substantially alter the N2O emission potential. Also, collectively considering soil-environmental regulators and their interactions associated with land conversion is crucial to predict and design mitigation strategies for N2O emissions from land-use change.
Collapse
Affiliation(s)
- Jinsen Zheng
- Forestry and Forest Products Research Institute, Tsukuba 305-8687, Japan.
| | - Tadashi Sakata
- Forestry and Forest Products Research Institute, Tsukuba 305-8687, Japan
| | - Kazumichi Fujii
- Forestry and Forest Products Research Institute, Tsukuba 305-8687, Japan.
| |
Collapse
|
4
|
Li Y, Liang Y, Zhang H, Liu Y, Zhu J, Xu J, Zhou Z, Ma J, Liu K, Yu F. Variation, distribution, and diversity of canonical ammonia-oxidizing microorganisms and complete-nitrifying bacteria in highly contaminated ecological restoration regions in the Siding mine area. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 217:112274. [PMID: 33930771 DOI: 10.1016/j.ecoenv.2021.112274] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 04/12/2021] [Accepted: 04/18/2021] [Indexed: 06/12/2023]
Abstract
Canonical ammonia-oxidizing archaea (AOA), ammonia-oxidizing bacteria (AOB) and complete-nitrifying bacteria (comammox) exist in a variety of ecosystems. However, little is known about AOA, AOB and comammox or their contributions to nitrification in the soils of heavily degraded and acidic mine regions. In the present study, the activity, richness, diversity and distribution patterns of AOA, AOB and comammox in the Siding mine area were investigated. Nemerow's multifactor pollution index (PN) values indicated that the soil in all three areas in the Siding mine area was highly contaminated by Cd, Pb, Zn, Mn and Cu. The AOA, AOB and comammox amoA gene copy numbers exhibited significant positive correlations with Pb and Zn levels and PN values, which indicated that the populations of AOA, AOB and comammox underwent adaptation and reproduction in response to pollution from multiple metals in the Siding mine area. Among them, the abundance of AOA was the highest, and AOA may survive better than AOB and comammox under such severely pollution-stressed and ammonia-limited conditions. The phyla Thaumarchaeota and Crenarchaeota may play vital roles in the soil ammonia oxidation process. Unlike AOA, AOB may use soil available phosphorus to help them compete for NH3 and other limiting nutrients with AOA and heterotrophs. Moreover, soil organic matter was the main factor influencing the species diversity of AOB, the β-diversity of AOB and comammox, and the community composition of AOA, AOB and comammox. Our research will help to explain the role and importance of AOA, AOB and comammox in the different ecological restoration regions in the Siding mine area.
Collapse
Affiliation(s)
- Yi Li
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, China; College of Environment and Resources, Guangxi Normal University, 541004 Guilin, China; Innovation Institute of Sustainable Development, Guangxi Normal University, 541004 Guilin, China
| | - Ying Liang
- College of Environment and Resources, Guangxi Normal University, 541004 Guilin, China
| | - Haichun Zhang
- College of Life Science, Guangxi Normal University, 541004 Guilin, China
| | - Yuan Liu
- College of Environment and Resources, Guangxi Normal University, 541004 Guilin, China
| | - Jing Zhu
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, China; College of Environment and Resources, Guangxi Normal University, 541004 Guilin, China
| | - Jie Xu
- College of Life Science, Guangxi Normal University, 541004 Guilin, China
| | - Zhenming Zhou
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, China; College of Environment and Resources, Guangxi Normal University, 541004 Guilin, China
| | - Jiangming Ma
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, China; College of Life Science, Guangxi Normal University, 541004 Guilin, China; Innovation Institute of Sustainable Development, Guangxi Normal University, 541004 Guilin, China
| | - Kehui Liu
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, China; College of Life Science, Guangxi Normal University, 541004 Guilin, China; Innovation Institute of Sustainable Development, Guangxi Normal University, 541004 Guilin, China.
| | - Fangming Yu
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, China; College of Environment and Resources, Guangxi Normal University, 541004 Guilin, China; Innovation Institute of Sustainable Development, Guangxi Normal University, 541004 Guilin, China.
| |
Collapse
|
5
|
Yang L, Zhu G, Ju X, Liu R. How nitrification-related N 2O is associated with soil ammonia oxidizers in two contrasting soils in China? THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 770:143212. [PMID: 33257072 DOI: 10.1016/j.scitotenv.2020.143212] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 10/13/2020] [Accepted: 10/17/2020] [Indexed: 06/12/2023]
Abstract
As a key process contributing to N2O emissions, nitrification is regulated by soil microbes and mainly affected by soil pH, NH3 availability, temperature and O2 availability. Current knowledge gaps include how nitrification-related N2O is associated with soil microbes in different pH soils. In the current study, a microcosm incubation experiment was conducted with two contrasting soils of different pH (5.08, 8.30) under controlled conditions. The soils were amended with ammonium sulphate ((NH4)2SO4, 50 mg N kg-1) combined with or without nitrification inhibitors and incubated under 20 °C, 65% water hold capacity (WHC) for three weeks. N2O fluxes, mineral nitrogen (N) concentrations and ammonia oxidizers populations were measured during the incubation to investigate the correlations of nitrification-related N2O with ammonia oxidizers. The nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) was used to inhibit nitrification albeit to various inhibition effects with different soils. Acetylene (0.1% v/v C2H2), an inhibitor of AOA and AOB ammonia monooxygenase (AMO), was used to distinguish N2O emissions by nitrifiers and denitrifiers. 1-octyne (5 μM aqueous), a selective specific AOB inhibitor, was used to assess the relative contributions of AOA and AOB to N2O emissions. The results showed that N2O yield for AOA and AOB varied with soil pH. AOB was the key microbial player in alkaline soil, contributing about 85% of nitrification-related N2O. Conversely, about 78% of nitrification-related N2O was contributed by AOA in acidic soil. Furthermore, there was a significant and positive relationship between mineral N (NO2-, NO3-), AOA and AOB populations and nitrification-related N2O in alkaline soil. However, in acidic soil, NO3- concentration and AOA had significantly positive relationships with nitrification-related N2O. To conclude, soil pH was a key factor affecting the contribution of ammonia oxidizers to nitrification-related N2O emissions. AOA-related N2O production dominated at low pH (5.08), while AOB-related N2O was favored in alkaline soil (pH 8.3).
Collapse
Affiliation(s)
- Liuqing Yang
- Beijing Key Laboratory of Farmyard Soil Pollution Prevention-control and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
| | - Gaodi Zhu
- College of Environmental and Resource Sciences, Zhejiang A&F University, Hangzhou 311300, China
| | - Xiaotang Ju
- College of Tropical Crops, Hainan University, Haikou 570228, China; Beijing Key Laboratory of Farmyard Soil Pollution Prevention-control and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.
| | - Rui Liu
- Beijing Key Laboratory of Farmyard Soil Pollution Prevention-control and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.
| |
Collapse
|
6
|
Zhang P, Wen T, Hu Y, Zhang J, Cai Z. Can N Fertilizer Addition Affect N 2O Isotopocule Signatures for Soil N 2O Source Partitioning? INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18095024. [PMID: 34068614 PMCID: PMC8126104 DOI: 10.3390/ijerph18095024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 04/22/2021] [Accepted: 04/27/2021] [Indexed: 11/24/2022]
Abstract
Isotopocule signatures of N2O (δ15Nbulk, δ18O and site preference) are useful for discerning soil N2O source, but sometimes, N fertilizer is needed to ensure that there is
enough N2O flux for accurate isotopocule measurements. However, whether fertilizer affects these measurements is unknown. This study evaluated a gradient of NH4NO3 addition on N2O productions and isotopocule values in two acidic subtropical soils. The results showed that N2O production rates obviously amplified with increasing NH4NO3 (p < 0.01), although a lower N2O production rate and an increasing extent appeared in forest soil. The δ15Nbulk of N2O produced in forest soil was progressively enriched when more NH4NO3 was added, while becoming
more depleted of agricultural soil. Moreover, the N2O site
preference (SP) values collectively elevated with increasing NH4NO3 in both soils, indicating that N2O contributions changed. The increased N2O production in agricultural soil was predominantly due to the added NH4NO3 via autotrophic nitrification and fungal denitrification (beyond 50%), which significantly
increased with added
NH4NO3, whereas soil organic nitrogen contributed most to N2O production in forest soil, probably via heterotrophic nitrification. Lacking the characteristic
SP
of heterotrophic nitrification,
its
N2O contribution
change
cannot be accurately identified yet. Overall, N fertilizer should be applied strictly according to the field application rate or N deposition amount when using isotopocule signatures to estimate soil N2O processes.
Collapse
Affiliation(s)
- Peiyi Zhang
- School of Geography Science, Nanjing Normal University, Nanjing 210023, China; (P.Z.); (Y.H.); (J.Z.); (Z.C.)
| | - Teng Wen
- School of Geography Science, Nanjing Normal University, Nanjing 210023, China; (P.Z.); (Y.H.); (J.Z.); (Z.C.)
- Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, China
- Key Laboratory of Virtual Geographic Environment (Nanjing Normal University), Ministry of Education, Nanjing 210023, China
- Correspondence: ; Tel.: +86-25-8589-1203
| | - Yangmei Hu
- School of Geography Science, Nanjing Normal University, Nanjing 210023, China; (P.Z.); (Y.H.); (J.Z.); (Z.C.)
| | - Jinbo Zhang
- School of Geography Science, Nanjing Normal University, Nanjing 210023, China; (P.Z.); (Y.H.); (J.Z.); (Z.C.)
- Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, China
- Key Laboratory of Virtual Geographic Environment (Nanjing Normal University), Ministry of Education, Nanjing 210023, China
| | - Zucong Cai
- School of Geography Science, Nanjing Normal University, Nanjing 210023, China; (P.Z.); (Y.H.); (J.Z.); (Z.C.)
- Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, China
- Key Laboratory of Virtual Geographic Environment (Nanjing Normal University), Ministry of Education, Nanjing 210023, China
| |
Collapse
|
7
|
Wang W, Han L, Zhang X, Wei K. Plastic film mulching affects N 2O emission and ammonia oxidizers in drip irrigated potato soil in northwest China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 754:142113. [PMID: 32920397 DOI: 10.1016/j.scitotenv.2020.142113] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Revised: 08/25/2020] [Accepted: 08/29/2020] [Indexed: 06/11/2023]
Abstract
In soil, ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) are regarded as key factors mediating nitrous oxide (N2O) production and emission. However, there are scarce reports about the effect of film mulching on ammonia oxidizers, and the biological nitrification process of N2O emission is unclear. This study was based on potato field experiments under different mulching films, including polyethylene mulching film (PM), transparent degradable mulching film (TDM), black degradable mulching film (BDM), and bare land (CK). AOB and AOA abundances were estimated using real-time PCR, and their diversity and community structure were measured using high-throughput sequencing. Result revealed that the total N2O emission from CK was 12.32%-41.03% higher than that from film mulching soil. Under film mulching, according to total N2O emission from soil and N2O concentration in soil treatments were ordered as PM > BDM > TDM, and N2O production was closely correlated with copy numbers of the amoA gene. BDM significantly increased the number of amoA-AOB gene copies (P < 0.01), and PM significantly increased the those of amoA-AOA (P < 0.01). BDM and TDM increased AOB operational taxonomic units (OTUs), Chao1, Simpson, and Shannon indices, while PM increased the AOA OTUs and Chao1 index. Variations in AOA abundance and diversity were closely related to soil mineral N and temperature changes induced by polyethylene film mulching (P < 0.05), whereas AOB showed no significant association with soil properties. Meanwhile, we did not find a distinct treatment effect on AOB community structure. Our findings indicate that (i) degradable film mulching increased AOB abundance and diversity and N2O concentration, but obviously reduced N2O emissions, and (ii) AOA were more sensitive than AOB to polyethylene mulching film.
Collapse
Affiliation(s)
- Wen Wang
- College of Life Science, Yulin University, Chongwen Road No.4, Yulin, 719000, Shaanxi, China.
| | - Lu Han
- College of Life Science, Yulin University, Chongwen Road No.4, Yulin, 719000, Shaanxi, China
| | - Xiong Zhang
- College of Life Science, Yulin University, Chongwen Road No.4, Yulin, 719000, Shaanxi, China
| | - Ku Wei
- College of Life Science, Yulin University, Chongwen Road No.4, Yulin, 719000, Shaanxi, China
| |
Collapse
|