C and N Cycling and Greenhouse Gases Emission in Agroecosystem

A special issue of Atmosphere (ISSN 2073-4433). This special issue belongs to the section "Biosphere/Hydrosphere/Land–Atmosphere Interactions".

Deadline for manuscript submissions: closed (31 October 2018) | Viewed by 43483

Special Issue Editor

Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan
Interests: organic matter management to enable soil carbon storage and improved crop productivity; appropriate land use management of peatlands
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Special Issue Information

Dear Colleagues,

The agriculture sector is an important source of greenhouse gas (CO2, CH4 and N2O) emissions to the atmosphere. IPCC reported that global anthropogenic greenhouse gases emission in 2010 increased to 49 Gt CO2 yr-1, in which CO2 emission from agriculture, forestry and other land uses accounts for 11%, and CH4 and N2O emissions from agriculture account for 8% and 4%, respectively. These emissions are caused by agricultural management practices, including landuse change, tillage, harvest, slash and burn, application of chemical fertilizer and manure, irrigation and drainage, grazing and animal husbandry, which influence C and N cycling in agroecosystems. However, some of agricultural management practices can mitigate environmental impacts, for example, manure and residue applications in upland field can enhance soil C sequestration, intermittent irrigation in paddy field can reduce CH4 emission, and increasing N use efficiency can reduce N2O emissions. An agroecosystem is, not only present as an ecosystem under agricultural management, but also connected to other ecosystems, including natural ecosystems. Therefore, comparative studies between agroecosystem and natural ecosystem, or synthetic studies in agricultural watersheds, are crucial to understand the magnitude of impacts from agricultural land use and management practices. Studies on the relationship between microbial activities (aerobic and anaerobic organic matter decomposition, nitrification and denitrification) and climate factors (temperature, precipitation, humidity, etc.) and soil environmental factors (soil temperature, soil moisture, groundwater level, soil pH, SOC, SON, mineral nitrogen, water soluble organic carbon, etc.) are also important to parameterization for simulation models. I would like to invite all of you, studying C and N cycling and greenhouse gas emissions in agroecosystems, to contribute your papers to this Special Issue.

Prof. Dr. Ryusuke Hatano
Guest Editor

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Keywords

  • C and N cycling in agroecosystem
  • greenhouse gases emission
  • landuse changes
  • agricultural management practices
  • soil C sequestration

Published Papers (10 papers)

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Research

18 pages, 1944 KiB  
Article
Effects of Grazing Pattern on Ecosystem Respiration and Methane Flux in a Sown Pasture in Inner Mongolia, China
by Baoling Mei, Hongyu Yue, Xunhua Zheng, William H. McDowell, Qingshan Zhao, Zaixing Zhou and Zhisheng Yao
Atmosphere 2019, 10(1), 5; https://doi.org/10.3390/atmos10010005 - 26 Dec 2018
Cited by 6 | Viewed by 3249
Abstract
The establishment of sown pasture is an important agricultural practice in many landscapes. Although both native grassland and sown pasture play a key role in the global carbon cycle, due to lack of data and field experiments, our understanding of grassland CH4 [...] Read more.
The establishment of sown pasture is an important agricultural practice in many landscapes. Although both native grassland and sown pasture play a key role in the global carbon cycle, due to lack of data and field experiments, our understanding of grassland CH4 fluxes and CO2 emissions remains limited, especially when it comes to sown pasture. We measured ecosystem respiration and CH4 fluxes in response to a variety of potential drivers (soil temperature, soil moisture, ammonium nitrogen, nitrate nitrogen and dissolved organic carbon) in CG (continuous grazing), RG (rotational grazing) and UG (ungrazed) plots in sown grassland for one year in Inner Mongolia. Fluxes of CH4 and ecosystem respiration were measured using static opaque chambers and gas chromatography. Grazing significantly reduced ecosystem respiration (p < 0.01), and grazing pattern significantly influenced respiration in CG and RG plots (p < 0.01). We find that the sown grassland is a net sink for atmospheric CH4. No influence of grazing pattern was observed on CH4 flux in CG, RG and UG (p > 0.05). Soil temperature is the most important factor influencing ecosystem respiration and CH4 flux in the sown grassland, with soil moisture playing a secondary role to soil temperature. Variation in levels of ammonium nitrogen, nitrate nitrogen and dissolved organic carbon had little influence on ecosystem respiration or CH4 flux (except in UG plots). The values obtained for ecosystem respiration of grasslands have a large uncertainty range, which may be due to spatial variability as well as differences in research methods. Mean CH4 fluxes measured only during the growing season were much higher than the annual mean CH4 fluxes. Full article
(This article belongs to the Special Issue C and N Cycling and Greenhouse Gases Emission in Agroecosystem)
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12 pages, 1153 KiB  
Article
Effects of Forage Rice Cultivation on Carbon and Greenhouse Gas Balances in a Rice Paddy Field
by Fumiaki Takakai, Masahiro Kobayashi, Takashi Sato, Kentaro Yasuda and Yoshihiro Kaneta
Atmosphere 2018, 9(12), 504; https://doi.org/10.3390/atmos9120504 - 19 Dec 2018
Cited by 3 | Viewed by 3602
Abstract
The effects of conversion from staple rice to forage rice on carbon and greenhouse gas (GHG) balances in a paddy field were evaluated. A staple rice plot without the application of livestock manure compost (LMC, S − M plot) and forage rice plots [...] Read more.
The effects of conversion from staple rice to forage rice on carbon and greenhouse gas (GHG) balances in a paddy field were evaluated. A staple rice plot without the application of livestock manure compost (LMC, S − M plot) and forage rice plots with and without the application of LMC, derived mainly from cattle (2 kg−FW m−2, F + M and F − M plots, respectively), were established. CH4 and N2O fluxes and CO2 flux from a bare soil plot for organic matter decomposition (OMD) were measured. The carbon budget was calculated by subtracting the OMD, CH4 emission, and harvested grain and straw (forage rice only) from the net primary production and LMC. The net GHG balance was calculated by integrating them as CO2 equivalents. There were no significant differences in GHG flux among the plots. Compared to the carbon loss in the S − M plot, the loss increased by harvesting straw and was mitigated by LMC application. The net GHG emission in the F + M plot was significantly lower than that in other plots (1.78 and 2.63−2.77 kg CO2-eq m−2 year−1, respectively). There is a possibility that GHG emissions could be suppressed by forage rice cultivation with the application of LMC. Full article
(This article belongs to the Special Issue C and N Cycling and Greenhouse Gases Emission in Agroecosystem)
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16 pages, 1418 KiB  
Article
Temporal Dynamics of Nitrous Oxide Emission and Nitrate Leaching in Renovated Grassland with Repeated Application of Manure and/or Chemical Fertilizer
by Arata Nagatake, Ikabongo Mukumbuta, Kaho Yasuda, Mariko Shimizu, Masahito Kawai and Ryusuke Hatano
Atmosphere 2018, 9(12), 485; https://doi.org/10.3390/atmos9120485 - 07 Dec 2018
Cited by 4 | Viewed by 3133
Abstract
Managed grassland is occasionally renovated to maintain plant productivity by killing old vegetation, ploughing, and reseeding. This study aimed to investigate the combined effect of grassland renovation and long-term manure application on the temporal dynamics of nitrous oxide (N2O) emission and [...] Read more.
Managed grassland is occasionally renovated to maintain plant productivity by killing old vegetation, ploughing, and reseeding. This study aimed to investigate the combined effect of grassland renovation and long-term manure application on the temporal dynamics of nitrous oxide (N2O) emission and nitrate nitrogen (NO3–N) leaching. The study was conducted from September 2013 to September 2016 in a managed grassland renovated in September 2013. In this grassland, two treatments were managed—chemical fertilizer application (F treatment) and the combined application of chemical fertilizer and beef cattle manure (MF treatment)—for eight years before the renovation. The control treatment without fertilization (CT) was newly established in the F treatment. The soil N2O flux was measured using a closed chamber method. A leachate sample was collected using a tension-free lysimeter that was installed at the bottom of the Ap horizon (25 cm deep), and total NO3–N leaching was calculated from leachate NO3–N concentration and drainage volume was estimated by the water balance method. In the first year after renovation, the absence of plant nitrogen uptake triggered NO3–N leaching following rainfall during renovation and increased drainage water after thawing. NO3–N movement from topsoil to deeper soil enhanced N2O production and emission from the soil. N2O emission in MF treatment was 1.6–2.0 times larger than those of CT and F treatments, and NO3–N leaching in MF treatment was 2.3–2.6 times larger than those of CT and F treatments in the first year. Mineral nitrogen release derived from long-term manure application increased NO3–N leaching and N2O emission. In the second year, N2O emission and NO3–N leaching significantly decreased from the first year because of increased plant N uptake and decreased mineral nitrogen surplus, and no significant differences in N2O emission and NO3–N leaching were observed among the treatments. In the second and third years, NO3–N leaching was regulated by plant nitrogen uptake. There were no significant differences in NO3–N leaching among the treatments, but N2O emission in MF treatment was significantly smaller than in the F treatment. Long-term manure application could be a possible option to mitigate N2O emission in permanent grassland; however, the risk of increased NO3–N leaching and N2O emission in the renovation year induced by manure nitrogen release should be noted. Full article
(This article belongs to the Special Issue C and N Cycling and Greenhouse Gases Emission in Agroecosystem)
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14 pages, 2219 KiB  
Article
Variation in Soil Properties Regulate Greenhouse Gas Fluxes and Global Warming Potential in Three Land Use Types on Tropical Peat
by Kiwamu Ishikura, Untung Darung, Takashi Inoue and Ryusuke Hatano
Atmosphere 2018, 9(12), 465; https://doi.org/10.3390/atmos9120465 - 27 Nov 2018
Cited by 20 | Viewed by 4334
Abstract
This study investigated spatial factors controlling CO2, CH4, and N2O fluxes and compared global warming potential (GWP) among undrained forest (UDF), drained forest (DF), and drained burned land (DBL) on tropical peatland in Central Kalimantan, Indonesia. Sampling [...] Read more.
This study investigated spatial factors controlling CO2, CH4, and N2O fluxes and compared global warming potential (GWP) among undrained forest (UDF), drained forest (DF), and drained burned land (DBL) on tropical peatland in Central Kalimantan, Indonesia. Sampling was performed once within two weeks in the beginning of dry season. CO2 flux was significantly promoted by lowering soil moisture and pH. The result suggests that oxidative peat decomposition was enhanced in drier position, and the decomposition acidify the peat soils. CH4 flux was significantly promoted by a rise in groundwater level, suggesting that methanogenesis was enhanced under anaerobic condition. N2O flux was promoted by increasing soil nitrate content in DF, suggesting that denitrification was promoted by substrate availability. On the other hand, N2O flux was promoted by lower soil C:N ratio and higher soil pH in DBL and UDF. CO2 flux was the highest in DF (241 mg C m−2 h−1) and was the lowest in DBL (94 mg C m−2 h−1), whereas CH4 flux was the highest in DBL (0.91 mg C m−2 h−1) and was the lowest in DF (0.01 mg C m−2 h−1), respectively. N2O flux was not significantly different among land uses. CO2 flux relatively contributed to 91–100% of GWP. In conclusion, it is necessary to decrease CO2 flux to mitigate GWP through a rise in groundwater level and soil moisture in the region. Full article
(This article belongs to the Special Issue C and N Cycling and Greenhouse Gases Emission in Agroecosystem)
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16 pages, 2787 KiB  
Article
Comparison of Closed Chamber and Eddy Covariance Methods to Improve the Understanding of Methane Fluxes from Rice Paddy Fields in Japan
by Nongpat Chaichana, Sonoko Dorothea Bellingrath-Kimura, Shujiro Komiya, Yoshiharu Fujii, Kosuke Noborio, Ottfried Dietrich and Tiwa Pakoktom
Atmosphere 2018, 9(9), 356; https://doi.org/10.3390/atmos9090356 - 15 Sep 2018
Cited by 20 | Viewed by 5301
Abstract
Greenhouse gas flux monitoring in ecosystems is mostly conducted by closed chamber and eddy covariance techniques. To determine the relevance of the two methods in rice paddy fields at different growing stages, closed chamber (CC) and eddy covariance (EC) methods were used to [...] Read more.
Greenhouse gas flux monitoring in ecosystems is mostly conducted by closed chamber and eddy covariance techniques. To determine the relevance of the two methods in rice paddy fields at different growing stages, closed chamber (CC) and eddy covariance (EC) methods were used to measure the methane (CH4) fluxes in a flooded rice paddy field. Intensive monitoring using the CC method was conducted at 30, 60 and 90 days after transplanting (DAT) and after harvest (AHV). An EC tower was installed at the centre of the experimental site to provide continuous measurements during the rice cropping season. The CC method resulted in CH4 flux averages that were 58%, 81%, 94% and 57% higher than those measured by the EC method at 30, 60 and 90 DAT and after harvest (AHV), respectively. A footprint analysis showed that the area covered by the EC method in this study included non-homogeneous land use types. The different strengths and weaknesses of the CC and EC methods can complement each other, and the use of both methods together leads to a better understanding of CH4 emissions from paddy fields. Full article
(This article belongs to the Special Issue C and N Cycling and Greenhouse Gases Emission in Agroecosystem)
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14 pages, 1315 KiB  
Article
Changes of Soil C Stock under Establishment and Abandonment of Arable Lands in Permafrost Area—Central Yakutia
by Alexey R. Desyatkin, Shinya Iwasaki, Roman V. Desyatkin and Ryusuke Hatano
Atmosphere 2018, 9(8), 308; https://doi.org/10.3390/atmos9080308 - 08 Aug 2018
Cited by 6 | Viewed by 3780
Abstract
Central Yakutia is in one of the most northern agricultural centers of the world. In this territory a notable area of arable land was made by removing the boreal Taiga with the primary purpose of crop cultivation. Such a method of cultivation significantly [...] Read more.
Central Yakutia is in one of the most northern agricultural centers of the world. In this territory a notable area of arable land was made by removing the boreal Taiga with the primary purpose of crop cultivation. Such a method of cultivation significantly changes soil total carbon (STC, soil organic carbon + soil carbonate carbon) balance, because of the destroyed upper humus horizon. Soil organic carbon (SOC) of cultivated arable lands is almost a half of that in forest. In abandoned arable lands with grass vegetation, the recovery of SOC has increased to 30% in comparison with cultivated arable lands. On arable lands recovering with new growth of trees, the SOC is related to the abandonment period. Soil carbonates carbon (SCC) content was significantly lower than SOC and showed significant difference among abandoned and other types of arable lands. Objectives of this study are to identify how STC stocks change in response to conversion of the forests to agricultural land and to analyze the arable land system’s recovery process after abandonment. Furthermore, after transformation of forest to arable land, a significant decrease of STC was observed, primarily due to mechanical loss after plant residue removal. It was also identified that the restoration and self-recovery of STC in abandoned arable lands of Central Yakutia continuously and slightly increase. Grass vegetation regenerates STC for 20 years. While the difference of average STC of forests and cultivated arable lands reached 41%, a new growth of forest on some abandoned arable land follows the tendency of STC decrease due to a low productivity level and suppressing effect on grass vegetation. Full article
(This article belongs to the Special Issue C and N Cycling and Greenhouse Gases Emission in Agroecosystem)
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11 pages, 839 KiB  
Article
Application of Farmyard Manure Rather Than Manure Slurry Mitigates the Net Greenhouse Gas Emissions from Herbage Production System in Nasu, Japan
by Akinori Mori
Atmosphere 2018, 9(7), 261; https://doi.org/10.3390/atmos9070261 - 12 Jul 2018
Cited by 4 | Viewed by 4252
Abstract
In Japan, it is important to recycle the nutrients in manure for forage production because most dairy cattle are fed inside, mainly with imported grain and home-grown roughage. To understand the overall effect of manure use on grassland on the net greenhouse gas [...] Read more.
In Japan, it is important to recycle the nutrients in manure for forage production because most dairy cattle are fed inside, mainly with imported grain and home-grown roughage. To understand the overall effect of manure use on grassland on the net greenhouse gas (GHG) emission and GHG intensity of herbage production systems, the integrated evaluation of emissions of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) is essential. The objective of this study was to compare the net GHG emissions (expressed in CO2-eq ha−1 y−1) and GHG intensity (expressed in CO2-eq Mg–1 dry matter yield) of herbage production based on manure slurry + synthetic fertilizer (slurry system) with that based on farmyard manure + synthetic fertilizer (FYM system). Calculations of net GHG emissions and GHG intensity took into account the net ecosystem carbon balance (NECB) in grassland, the CH4 and N2O emissions from grassland, and GHG emissions related to cattle waste management, synthetic fertilizer manufacture, and fuel consumption for grassland management based on literature data from previous studies. The net GHG emissions and GHG intensity were 36% (6.9 Mg CO2-eq ha−1 y−1) and 41% (0.89 Mg CO2-eq Mg−1), respectively, lower in the FYM system. Full article
(This article belongs to the Special Issue C and N Cycling and Greenhouse Gases Emission in Agroecosystem)
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18 pages, 1461 KiB  
Article
Impact of Management Practices on Methane Emissions from Paddy Grown on Mineral Soil over Peat in Central Hokkaido, Japan
by Habib Mohammad Naser, Osamu Nagata, Sarmin Sultana and Ryusuke Hatano
Atmosphere 2018, 9(6), 212; https://doi.org/10.3390/atmos9060212 - 31 May 2018
Cited by 4 | Viewed by 4805
Abstract
This study was carried out at Kita-mura near Bibai located in central Hokkaido, Japan, with the intention of investigating the effects of different agronomical managements on CH4 emissions from paddy fields on mineral soil over peat under farmers’ actual management conditions in [...] Read more.
This study was carried out at Kita-mura near Bibai located in central Hokkaido, Japan, with the intention of investigating the effects of different agronomical managements on CH4 emissions from paddy fields on mineral soil over peat under farmers’ actual management conditions in the snowy temperate region. Four fields were studied, including two fields with twice drainage (D1-M and D2-M) and also a single-drainage field (D3-S) under annual single-cropping and a paddy-fallow-paddy crop rotation as their systems. The other field was under single cropping annual with continuous flooding (CF-R) in the pattern of soybean (upland crop)-fallow-paddy. The mineral-soil thickness of these soil-dressed peatland fields varied from 20 to 47 cm. The amount of crop residues leftover in the fields ranged from 277 to 751 g dry matter m−2. Total CH4 emissions ranged from 25.3 to 116 g CH4-C m−2 per growing season. There was a significant relationship between crop-residue carbon (C) and total CH4 emissions during the rice-growing season. Methane fluxes from paddy soils had a strong interaction between readily available C source for methanogens and anaerobic conditions created by water management. Despite the differences in water regime and soil type, the average values of straw’s efficiency on CH4 production in this study were significantly higher than those of southern Japan and statistically identical with central Hokkaido. Our results suggest that the environmental conditions of central Hokkaido in association with crop-residue management had a significant influence on CH4 emission from paddy fields on mineral soil over peat. Rotation soybean (upland)-to-paddy followed by drainage-twice practices also largely reduces CH4 emission. However, mineral-soil dressing on peat could have a significant impact on suppression of CH4 emissions from beneath the peat reservoir. Full article
(This article belongs to the Special Issue C and N Cycling and Greenhouse Gases Emission in Agroecosystem)
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16 pages, 1492 KiB  
Article
Returning Tea Pruning Residue and Its Biochar Had a Contrasting Effect on Soil N2O and CO2 Emissions from Tea Plantation Soil
by Aung Zaw Oo, Shigeto Sudo, Khin Thuzar Win, Akira Shibata, Tomohito Sano and Yuhei Hirono
Atmosphere 2018, 9(3), 109; https://doi.org/10.3390/atmos9030109 - 15 Mar 2018
Cited by 12 | Viewed by 5455
Abstract
A laboratory incubation experiment is conducted for 90 days under controlled conditions where either pruning residue or its biochar is applied to determine which application generates the lowest amount of greenhouse gas from tea plantation soil. To study the effect of incorporation depth [...] Read more.
A laboratory incubation experiment is conducted for 90 days under controlled conditions where either pruning residue or its biochar is applied to determine which application generates the lowest amount of greenhouse gas from tea plantation soil. To study the effect of incorporation depth on soil N2O and CO2 emissions, experiment 1 is performed with three treatments: (1) control; (2) tea pruning residue; and (3) residue biochar mixed with soil from two different depths (0–5 cm and 0–10 cm layers). In experiment 2, only the 0–10 cm soil layer is used to study the effect of surface application of tea pruning residue or its biochar on soil N2O and CO2 emissions compared with the control. The results show that biochar significantly increases soil pH, total C and C/N ratio in both experiments. The addition of pruning residue significantly increases soil total C content, cumulative N2O and CO2 emissions after 90 days of incubation. Converting pruning residue to biochar and its application significantly decreases cumulative N2O emission by 17.7% and 74.2% from the 0–5 cm and 0–10 cm soil layers, respectively, compared to their respective controls. However, biochar addition increases soil CO2 emissions for both the soil layers in experiment 1. Surface application of biochar to soil significantly reduces both N2O and CO2 emissions compared to residue treatment and the control in experiment 2. Our results suggest that converting pruning residue to biochar and its addition to soil has the potential to mitigate soil N2O emissions from tea plantation. Full article
(This article belongs to the Special Issue C and N Cycling and Greenhouse Gases Emission in Agroecosystem)
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2445 KiB  
Article
Effects of N Fertilizer Application on Soil N2O Emissions and CH4 Uptake: A Two-Year Study in an Apple Orchard in Eastern China
by Baohua Xie, Jiangxin Gu, Junbao Yu, Guangxuan Han, Xunhua Zheng, Yu Xu and Haitao Lin
Atmosphere 2017, 8(10), 181; https://doi.org/10.3390/atmos8100181 - 21 Sep 2017
Cited by 19 | Viewed by 4607
Abstract
Land use changes from cropland to orchards in Eastern China have raised serious concerns about the regional nitrogen (N) cycle and greenhouse gas balance. We measured soil nitrous oxide (N2O) emissions and methane (CH4) uptake using manual static chambers [...] Read more.
Land use changes from cropland to orchards in Eastern China have raised serious concerns about the regional nitrogen (N) cycle and greenhouse gas balance. We measured soil nitrous oxide (N2O) emissions and methane (CH4) uptake using manual static chambers in an apple orchard. The primary aims were to assess the effect of N fertilizer application on gas fluxes and quantify the site-specific N2O emission factor (EFd). Field experiments were arranged in a randomized block design with three N input rates (0, 800 and 2600/2000 kg N ha−1 year−1). We found that orchard soils were a negligible CH4 sink (−1.1 to −0.4 kg C ha−1 year−1). Annual N2O emissions responded positively to N input rates, ranging from 34.1 to 60.3 kg N ha−1 year−1. EFd ranged from 1.00% to 1.65% with a mean of 1.34%. The extremely large background emissions of N2O (34.1–34.3 kg N ha−1 year−1) most likely originated from nitrate accumulation in the soil profile because of historical overuse of N fertilizer. We conclude that (1) site-specific EFd is suitable for assessing regional direct N2O emissions from upland orchards; and (2) conventional fertilization regimes must be avoided, and reduced N input rates are recommended in the study region. Full article
(This article belongs to the Special Issue C and N Cycling and Greenhouse Gases Emission in Agroecosystem)
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