DOI: 10.1016/j.jag.2016.03.002
Scopus记录号: 2-s2.0-85022091532
论文题名: Effects of the partitioning of diffuse and direct solar radiation on satellite-based modeling of crop gross primary production
作者: Xin Q ; , Gong P ; , Suyker A ; E ; , Si Y
刊名: International Journal of Applied Earth Observation and Geoinformation
ISSN: 15698432
出版年: 2016
卷: 50 起始页码: 51
结束页码: 63
语种: 英语
英文关键词: Carbon cycle
; Crop yield
; Flux tower
; Light use efficiency
; Remote sensing
Scopus关键词: carbon cycle
; crop yield
; diffusion
; light use efficiency
; modeling
; partitioning
; primary production
; remote sensing
; solar radiation
; Glycine max
; Zea mays
英文摘要: Modeling crop gross primary production (GPP) is critical to understanding the carbon dynamics of agro-ecosystems. Satellite-based studies have widely used production efficiency models (PEM) to estimate cropland GPP, wherein light use efficiency (LUE) is a key model parameter. One factor that has not been well considered in many PEMs is that canopy LUE could vary with illumination conditions. This study investigates how the partitioning of diffuse and direct solar radiation influences cropland GPP using both flux tower and satellite data. The field-measured hourly LUE under cloudy conditions was 1.50 and 1.70 times higher than that under near clear-sky conditions for irrigated corn and soybean, respectively. We applied a two-leaf model to simulate the canopy radiative transfer process, where modeled photosynthetically active radiation (PAR) absorbed by canopy agreed with tower measurements (R2 = 0.959 and 0.914 for corn and soybean, respectively). Derived canopy LUE became similar after accounting for the impact of light saturation on leaf photosynthetic capacity under varied illumination conditions. The impacts of solar radiation partitioning on satellite-based modeling of crop GPP was examined using vegetation indices (VI) derived from MODIS data. Consistent with the field modeling results, the relationship between daily GPP and PAR × VI under varied illumination conditions showed different patterns in terms of regression slope and intercept. We proposed a function to correct the influences of direct and diffuse radiation partitioning and the explained variance of flux tower GPP increased in all experiments. Our results suggest that the non-linear response of leaf photosynthesis to light absorption contributes to higher canopy LUE on cloudy days than on clear days. We conclude that accounting for the impacts of solar radiation partitioning is necessary for modeling crop GPP on a daily or shorter basis. © 2016 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/80072
Appears in Collections: 气候变化事实与影响
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作者单位: Ministry of Education Key Laboratory for Earth System Modeling, Tsinghua University, Beijing, China; Key Lab of Urbanization and Geo-simulation, Sun Yat-Sen University, Guangzhou, China; Joint Center for Global Change Studies, Beijing, China; School of Natural Resources, University of Nebraska-LincolnNE, United States
Recommended Citation:
Xin Q,, Gong P,, Suyker A,et al. Effects of the partitioning of diffuse and direct solar radiation on satellite-based modeling of crop gross primary production[J]. International Journal of Applied Earth Observation and Geoinformation,2016-01-01,50