当前位置: X-MOL 学术Biogeosciences › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Simulating measurable ecosystem carbon and nitrogen dynamics with the mechanistically defined MEMS 2.0 model
Biogeosciences ( IF 4.9 ) Pub Date : 2021-05-26 , DOI: 10.5194/bg-18-3147-2021
Yao Zhang , Jocelyn M. Lavallee , Andy D. Robertson , Rebecca Even , Stephen M. Ogle , Keith Paustian , M. Francesca Cotrufo

For decades, predominant soil biogeochemical models have used conceptual soil organic matter (SOM) pools and only simulated them to a shallow depth in soil. Efforts to overcome these limitations have prompted the development of the new generation SOM models, including MEMS 1.0, which represents measurable biophysical SOM fractions, over the entire root zone, and embodies recent understanding of the processes that govern SOM dynamics. Here we present the result of continued development of the MEMS model, version 2.0. MEMS 2.0 is a full ecosystem model with modules simulating plant growth with above- and belowground inputs, soil water and temperature by layer, decomposition of plant inputs and SOM, and mineralization and immobilization of nitrogen (N). The model simulates two commonly measured SOM pools – particulate and mineral-associated organic matter (POM and MAOM, respectively). We present results of calibration and validation of the model with several grassland sites in the US. MEMS 2.0 generally captured the soil carbon (C) stocks (R2 of 0.89 and 0.6 for calibration and validation, respectively) and their distributions between POM and MAOM throughout the entire soil profile. The simulated soil N matches measurements but with lower accuracy (R2 of 0.73 and 0.31 for calibration and validation of total N in SOM, respectively) than for soil C. Simulated soil water and temperature were compared with measurements, and the accuracy is comparable to the other commonly used models. The seasonal variation in gross primary production (GPP; R2= 0.83), ecosystem respiration (ER; R2= 0.89), net ecosystem exchange (NEE; R2= 0.67), and evapotranspiration (ET; R2= 0.71) was well captured by the model. We will further develop the model to represent forest and agricultural systems and improve it to incorporate new understanding of SOM decomposition.

中文翻译:

通过机械定义的MEMS 2.0模型模拟可测量的生态系统碳和氮动力学

几十年来,主要的土壤生物地球化学模型使用概念性土壤有机质(SOM)池,并且仅对土壤中的浅层深度进行了模拟。克服这些局限性的努力促使开发了新一代SOM模型,包括MEMS 1.0,它代表了整个根域上可测量的生物物理SOM分数,体现了对控制SOM动力学的过程的最新理解。在这里,我们介绍了MEMS模型2.0版的持续开发结果。MEMS 2.0是一个完整的生态系统模型,其模块模拟地上和地下输入的植物生长,土壤水和层的温度,植物输入和SOM的分解以及氮(N)的矿化和固定化。该模型模拟了两个通常测量的SOM池-颗粒物和与矿物相关的有机物(分别为POM和MAOM)。我们介绍了在美国多个草原站点对模型进行校准和验证的结果。MEMS 2.0通常会捕获土壤碳(C)存量(R 2分别为0.89和0.6(分别用于校准和验证)及其在整个土壤剖面中POM和MAOM之间的分布。模拟的土壤N与测量值相匹配,但精度比土壤C更低(SOM中总N的校准和验证的R 2分别为0.73和0.31)。将模拟的土壤水和温度与测量值进行比较,其精度与其他常用的模型。初级生产总值(GPP; R 2 =  0.83),生态系统呼吸作用(ER; R 2 =  0.89),生态系统净交换量(NEE; R 2 =  0.67)和蒸散量(ET;R 2 =  0.71)被模型很好地捕获了。我们将进一步开发代表森林和农业系统的模型,并对其进行改进以纳入对SOM分解的新理解。
更新日期:2021-05-26
down
wechat
bug