Testing DNDC model for simulating soil respiration and assessing the effects of climate change on the CO2 gas flux from Irish agriculture
Testing DNDC model for simulating soil respiration and assessing the effects of climate change on the CO2 gas flux from Irish agriculture
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DOI：
10.1016/j.gloplacha.2011.05.011
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发表时间：
2011-08-01
影响因子：
3.9
通讯作者：
Williams, M.
中科院分区：
文献类型：
--
作者：
Abdalla, M.;Kumar, S.;Williams, M.
模拟模型对于研究气候变化对陆地生态系统温室气体排放的潜在影响很有价值。DNDC（脱硝-脱组分模型）进行了测试，从邻近的牧场和耕地在爱尔兰中部地区的土壤呼吸观测数据。大约50年前，耕地从草地转变为草地，自2003年以来，采用两种不同的耕作制度进行管理：传统耕作和减少耕作。这两个领域都位于相同的土壤类型，归类为自由排水桑迪壤土来自河流冰川砾石与低土壤持水能力。2003年1月至2005年8月进行了土壤呼吸测量。对三种气候情景进行了研究，一种是实地气象站测量的气候数据基线，另一种是爱尔兰社区气候变化联合会（C4 I）根据哈德利中心全球气候模式（HadCM（3））和政府间气候变化专门委员会（IPCC）A1 B排放情景预测的高低温敏感性情景。本研究的目的是使用测量的土壤呼吸速率，以验证DNDC模型估计从这些关键的爱尔兰土壤中的CO2排放，研究未来气候变化对CO2排放的影响，并估计排放的不确定性，由于使用不同的未来气候预测。结果表明，DNDC模型可以可靠地估计土壤呼吸从两个领域检查。该模型低估了从牧场每年测量的CO2排放量仅为13%（模型效率：ME = 0.6，均方根误差：RMSE = 1.9，平均绝对误差：MAE = 6.3）与常规耕作和少耕的模型效率相比，差异有9%（ME = 0.6; RMSE = 1.6和MAE = 2.4）和8%（ME = 0.23; RMSE = 1.8和MAE = 2.9）。短期土地利用变化对土壤CO2排放没有显著影响。使用高温度敏感性的情况下，未来的碳排放量将增加15%的牧场和14%和16%的耕地传统和减少耕作制度，分别。然而，在低温度敏感性的情况下，较低的增加C流出的6%的牧场和5%的耕地进行了预测。计算出的年CO2排放量的不确定性，使用高，低温敏感性的情况下，9%的牧场和8%的耕地。(C)2011 Elsevier B. V.保留所有权利。
Simulation models can be valuable to investigate potential effects of climate change on greenhouse gas emissions from terrestrial ecosystems. DNDC (the DeNitrification-DeComposition model) was tested against observed soil respiration data from adjacent pasture and arable fields in the Irish midlands. The arable field was converted from grassland approximately 50 years ago and managed since 2003 under two different tillage systems; conventional and reduced tillage. Both fields were located on the same soil type, classified as a free draining sandy loam soil derived from fluvial glacial gravels with low soil moisture holding capacity. Soil respiration measurements were made from January 2003 to August 2005. Three climate scenarios were investigated, a baseline of measured climatic data from a weather station at the field site, and high and low temperature sensitivity scenarios predicted by the Community Climate Change Consortium for Ireland (C4I) based on the Hadley Centre Global Climate Model (HadCM(3)) and the Intergovernment Panel on Climate Change (IPCC) A1B emission scenario. The aims of this study were to use measured soil respiration rates to validate the DNDC model for estimating CO2 efflux from these key Irish soils, investigate the effects of future climate change on CO2 efflux and estimate the efflux uncertainties due to using different future climate projections. The results indicate that the DNDC model can reliably estimate soil respiration from the two fields examined. The model underestimated annual measured CO2 efflux from the pasture by only13% (model efficiency: ME = 0.6; root mean square error: RMSE = 1.9 and mean absolute error: MAE = 6.3) and that from the arable conventional and reduced tillage by 9% (ME = 0.6; RMSE = 1.6 and MAE = 2.4) and 8% (ME = 0.23; RMSE = 1.8 and MAE = 2.9), respectively. Short-term land use change had no significant effects on CO2 effluxes from soil. Using the high temperature sensitivity scenario, future C effluxes would increase by 15% for the pasture and 14 and 16% for the arable conventional and reduced tillage systems, respectively. However, under the low temperature sensitivity scenario, lower increases in the C efflux of 6% for the pasture and 5% for the arable field were predicted. The calculated annual CO2 efflux uncertainties for using the high and low temperature sensitivity scenarios were 9% for the pasture and 8% for the arable field. (C) 2011 Elsevier B.V. All rights reserved.