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Physical Sciences and Mathematics Commons™
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Articles 1 - 8 of 8
Full-Text Articles in Physical Sciences and Mathematics
Gas Exchange Measurements In The Unsteady State, Aaron J. Saathoff, Jonathan Mark Welles
Gas Exchange Measurements In The Unsteady State, Aaron J. Saathoff, Jonathan Mark Welles
School of Natural Resources: Faculty Publications
Leaf level gas exchange is a widely used technique that provides real-time measurement of leaf physiological properties, including CO2 assimilation (A), stomatal conductance to water vapour (gsw) and intercellular CO2 (Ci). Modern open-path gas exchange systems offer greater portability than the laboratory-built systems of the past and take advantage of high-precision infrared gas analyzers and optimized system design. However, the basic measurement paradigm has long required steadystate conditions for accurate measurement. For CO2 response curves, this requirement has meant that each point on the curve needs 1–3 min and a full response curve …
Parallel Seasonal Patterns Of Photosynthesis, Fluorescence, And Reflectance Indices In Boreal Trees, Kyle R. Springer, Ran Wang, John A. Gamon
Parallel Seasonal Patterns Of Photosynthesis, Fluorescence, And Reflectance Indices In Boreal Trees, Kyle R. Springer, Ran Wang, John A. Gamon
School of Natural Resources: Faculty Publications
Tree species in the boreal forest cycle between periods of active growth and dormancy alter their photosynthetic processes in response to changing environmental conditions. For deciduous species, these changes are readily visible, while evergreen species have subtler foliar changes during seasonal transitions. In this study, we used remotely sensed optical indices to observe seasonal changes in photosynthetic activity, or photosynthetic phenology, of six boreal tree species. We evaluated the normalized difference vegetation index (NDVI), the photochemical reflectance index (PRI), the chlorophyll/carotenoid index (CCI), and steady-state chlorophyll fluorescence (FS) as a measure of solar-induced fluorescence (SIF), and compared these …
Parallel Seasonal Patterns Of Photosynthesis, Fluorescence, And Reflectance Indices In Boreal Trees, Kyle R. Springer, Ran Wang, John A. Gamon
Parallel Seasonal Patterns Of Photosynthesis, Fluorescence, And Reflectance Indices In Boreal Trees, Kyle R. Springer, Ran Wang, John A. Gamon
School of Natural Resources: Faculty Publications
Tree species in the boreal forest cycle between periods of active growth and dormancy alter their photosynthetic processes in response to changing environmental conditions. For deciduous species, these changes are readily visible, while evergreen species have subtler foliar changes during seasonal transitions. In this study, we used remotely sensed optical indices to observe seasonal changes in photosynthetic activity, or photosynthetic phenology, of six boreal tree species. We evaluated the normalized difference vegetation index (NDVI), the photochemical reflectance index (PRI), the chlorophyll/carotenoid index (CCI), and steady-state chlorophyll fluorescence (FS) as a measure of solar-induced fluorescence (SIF), and compared these …
Productivity, Absorbed Photosynthetically Active Radiation, And Light Use Efficiency In Crops: Implications For Remote Sensing Of Crop Primary Production, Anatoly A. Gitelson, Yi Peng, Timothy J. Arkebauer, Andrew E. Suyker
Productivity, Absorbed Photosynthetically Active Radiation, And Light Use Efficiency In Crops: Implications For Remote Sensing Of Crop Primary Production, Anatoly A. Gitelson, Yi Peng, Timothy J. Arkebauer, Andrew E. Suyker
School of Natural Resources: Faculty Publications
Vegetation productivity metrics such as gross primary production (GPP) at the canopy scale are greatly affected by the efficiency of using absorbed radiation for photosynthesis, or light use efficiency (LUE). Thus, close investigation of the relationships between canopy GPP and photosynthetically active radiation absorbed by vegetation is the basis for quantification of LUE. We used multiyear observations over irrigated and rainfed contrasting C3 (soybean) and C4 (maize) crops having different physiology, leaf structure, and canopy architecture to establish the relationships between canopy GPP and radiation absorbed by vegetation and quantify LUE. Although multiple LUE definitions are reported in the literature, …
Photosynthetic Response Of Soybean To Twospotted Spider Mite (Acari: Tetranychydae) Injury, Adeney De Freitas Bueno, Regiane Cristina Oliveira De Freitas Bueno, Paul David Nabity, Leon George Higley, Odair Aparecido Fernandes
Photosynthetic Response Of Soybean To Twospotted Spider Mite (Acari: Tetranychydae) Injury, Adeney De Freitas Bueno, Regiane Cristina Oliveira De Freitas Bueno, Paul David Nabity, Leon George Higley, Odair Aparecido Fernandes
School of Natural Resources: Faculty Publications
The twospotted spider mite Tetranychus urticae Koch is a common pest on soybean plants. To clarify plantarthropod interaction on mite-soybean system, leaf fluorescence, photosynthetic responses to variable carbon dioxide levels, and chlorophyll content were evaluated. Significant photosynthetic rate reduction was observed due to stomatal limitation. Stomatal closure was the major plant physiological response. As a consequence, there was reduction in photosynthetic rates. Surprisingly, plants did not show chlorophyll content reduction associated with photosynthetic impairment. No differences in fluorescence data indicate that T. urticae injury did not impair the function of light harvesting and photoelectron transport. These results showed that T. …
Photosynthesis And Stomatal Conductance Related To Reflectance On The Canopy Scale, S. B. Verma
Photosynthesis And Stomatal Conductance Related To Reflectance On The Canopy Scale, S. B. Verma
School of Natural Resources: Faculty Publications
No abstract provided.
Modeling Canopy Photosynthesis: Scaling Up From A Leaf To Canopy In A Temperate Grassland Ecosystem, S. B. Verma
Modeling Canopy Photosynthesis: Scaling Up From A Leaf To Canopy In A Temperate Grassland Ecosystem, S. B. Verma
School of Natural Resources: Faculty Publications
No abstract provided.
Simultaneous Determination Of Short-Period Photosynthesis And Evapotranspiration (Horticulture And Forestry Progress Report No. 91), Norman J. Rosenberg
Simultaneous Determination Of Short-Period Photosynthesis And Evapotranspiration (Horticulture And Forestry Progress Report No. 91), Norman J. Rosenberg
School of Natural Resources: Faculty Publications
No abstract provided.