DOI: 10.5194/hess-20-3859-2016
Scopus记录号: 2-s2.0-84988697972
论文题名: Incorporation of globally available datasets into the roving cosmic-ray neutron probe method for estimating field-scale soil water content
作者: Alexander Avery W ; , Finkenbiner C ; , Franz T ; E ; , Wang T ; , Nguy-Robertson A ; L ; , Suyker A ; , Arkebauer T ; , Muñoz-Arriola F
刊名: Hydrology and Earth System Sciences
ISSN: 10275606
出版年: 2016
卷: 20, 期: 9 起始页码: 3859
结束页码: 3872
语种: 英语
Scopus关键词: Biomass
; Calibration
; Cosmology
; Neutrons
; Organic carbon
; Probes
; Soil moisture
; Soils
; Statistical tests
; Uncertainty analysis
; Vegetation
; Accurate estimation
; Calibration equations
; Calibration parameters
; Error propagation analysis
; In-situ calibration
; Low-energy neutrons
; Scientific discipline
; Soil organic carbon
; Cosmic rays
; biomass
; bulk density
; data set
; estimation method
; forest ecosystem
; global perspective
; grassland
; in situ measurement
; MODIS
; Monte Carlo analysis
; organic carbon
; soil carbon
; soil texture
; soil water
; vegetation index
; water content
; United States
; Glycine max
; Zea mays
英文摘要: The need for accurate, real-time, reliable, and multi-scale soil water content (SWC) monitoring is critical for a multitude of scientific disciplines trying to understand and predict the Earth's terrestrial energy, water, and nutrient cycles. One promising technique to help meet this demand is fixed and roving cosmic-ray neutron probes (CRNPs). However, the relationship between observed low-energy neutrons and SWC is affected by local soil and vegetation calibration parameters. This effect may be accounted for by a calibration equation based on local soil type and the amount of vegetation. However, determining the calibration parameters for this equation is labor- and time-intensive, thus limiting the full potential of the roving CRNP in large surveys and long transects, or its use in novel environments. In this work, our objective is to develop and test the accuracy of globally available datasets (clay weight percent, soil bulk density, and soil organic carbon) to support the operability of the roving CRNP. Here, we develop a 1km product of soil lattice water over the continental United States (CONUS) using a database of in situ calibration samples and globally available soil taxonomy and soil texture data. We then test the accuracy of the global dataset in the CONUS using comparisons from 61 in situ samples of clay percent (RMSE = 5.45wt%, R2 = 0.68), soil bulk density (RMSE = 0.173g cm-3, R2 = 0.203), and soil organic carbon (RMSE = 1.47wt%, R2 = 0.175). Next, we conduct an uncertainty analysis of the global soil calibration parameters using a Monte Carlo error propagation analysis (maximum RMSE ∼ 0.035 cm3 cm-3 at a SWC = 0.40 cm3 cm-3). In terms of vegetation, fast-growing crops (i.e., maize and soybeans), grasslands, and forests contribute to the CRNP signal primarily through the water within their biomass and this signal must be accounted for accurate estimation of SWC. We estimated the biomass water signal by using a vegetation index derived from MODIS imagery as a proxy for standing wet biomass (RMSE < 1kgm-2). Lastly, we make recommendations on the design and validation of future roving CRNP experiments. © Author(s) 2016.
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/78728
Appears in Collections: 气候变化事实与影响
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作者单位: School of Natural Resources, University of Nebraska-Lincoln, Lincoln, NE, United States; Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE, United States; Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, NE, United States
Recommended Citation:
Alexander Avery W,, Finkenbiner C,, Franz T,et al. Incorporation of globally available datasets into the roving cosmic-ray neutron probe method for estimating field-scale soil water content[J]. Hydrology and Earth System Sciences,2016-01-01,20(9)