气候变化领域集成服务门户(CCPortal): Are there memory effects on greenhouse gas emissions (CO2; N2O and CH4) following grassland restoration?

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DOI	10.5194/bg-18-1481-2021
	Are there memory effects on greenhouse gas emissions (CO2; N2O and CH4) following grassland restoration?
	Merbold L.; Decock C.; Eugster W.; Fuchs K.; Wolf B.; Buchmann N.; Hörtnagl L.
发表日期	2021
ISSN	17264170
起始页码	1481
结束页码	1498
卷号	18 期号:4
英文摘要	A 5-year greenhouse gas (GHG) exchange study of the three major gas species (CO2, CH4 and N2O) from an intensively managed permanent grassland in Switzerland is presented. Measurements comprise 2 years (2010 and 2011) of manual static chamber measurements of CH4 and N2O, 5 years of continuous eddy covariance (EC) measurements (CO2-H2O - 2010-2014), and 3 years (2012-2014) of EC measurement of CH4 and N2O. Intensive grassland management included both regular and sporadic management activities. Regular management practices encompassed mowing (three to five cuts per year) with subsequent organic fertilizer amendments and occasional grazing, whereas sporadic management activities comprised grazing or similar activities. The primary objective of our measurements was to compare pre-plowing to post-plowing GHG exchange and to identify potential memory effects of such a substantial disturbance on GHG exchange and carbon (C) and nitrogen (N) gains and losses. In order to include measurements carried out with different observation techniques, we tested two different measurement techniques jointly in 2013, namely the manual static chamber approach and the eddy covariance technique for N2O, to quantify the GHG exchange from the observed grassland site. Our results showed that there were no memory effects on N2O and CH4 emissions after plowing, whereas the CO2 uptake of the site considerably increased when compared to pre-restoration years. In detail, we observed large losses of CO2 and N2O during the year of restoration. In contrast, the grassland acted as a carbon sink under usual management, i.e., the time periods 2010-2011 and 2013-2014. Enhanced emissions and emission peaks of N2O (defined as exceeding background emissions 0.21±0.55 nmolm-2 s-1 (SE=0.02) for at least 2 sequential days and the 7 d moving average exceeding background emissions) were observed for almost 7 continuous months after restoration as well as following organic fertilizer applications during all years. Net ecosystem exchange of CO2 (NEECO2) showed a common pattern of increased uptake of CO2 in spring and reduced uptake in late fall. NEECO2 dropped to zero and became positive after each harvest event. Methane (CH4) exchange fluctuated around zero during all years. Overall, CH4 exchange was of negligible importance for both the GHG budget and the carbon budget of the site. Our results stress the inclusion of grassland restoration events when providing cumulative sums of C sequestration potential and/or global warming potential (GWP). Consequently, this study further highlights the need for continuous long-term GHG exchange observations as well as for the implementation of our findings into biogeochemical process models to track potential GHG mitigation objectives as well as to predict future GHG emission scenarios reliably. © Author(s) 2021.
scopus关键词	carbon cycle; carbon dioxide; carbon emission; environmental restoration; grassland; greenhouse gas; methane
来源期刊	Biogeosciences
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/177219
作者单位	Grassland Sciences Group, Department of Environmental Systems Science, Institute of Agricultural Sciences, ETH Zurich, Universitätsstrasse 2, Zurich, 8092, Switzerland; Mazingira Centre, International Livestock Research Institute (ILRI), Old Naivasha Road, P.O. Box 30709, Nairobi, 00100, Kenya; Sustainable Agroecosystems Group, Department of Environmental Systems Science, Institute of Agricultural Sciences, ETH Zurich, Universitätsstrasse 2, Zurich, 8092, Switzerland; Institute of Meteorology and Climate Research (IMK-IFU), Karlsruhe Institute of Technology (KIT), Kreuzeckbahnstrasse 19, Garmisch-Partenkirchen, 82467, Germany; Research Division for Agroecology and Environment, Agroscope, Reckenholzstrasse 191, Zurich, 8046, Switzerland; Department of Natural Resources Management and Environmental Sciences, California Polytechnic State University, San Luis Obispo, CA, United States
推荐引用方式 GB/T 7714	Merbold L.,Decock C.,Eugster W.,et al. Are there memory effects on greenhouse gas emissions (CO2; N2O and CH4) following grassland restoration?[J],2021,18(4).
APA	Merbold L..,Decock C..,Eugster W..,Fuchs K..,Wolf B..,...&Hörtnagl L..(2021).Are there memory effects on greenhouse gas emissions (CO2; N2O and CH4) following grassland restoration?.Biogeosciences,18(4).
MLA	Merbold L.,et al."Are there memory effects on greenhouse gas emissions (CO2; N2O and CH4) following grassland restoration?".Biogeosciences 18.4(2021).