Jun 16, 2011 ... Title: Evaluation of fraction of absorbed photosynthetically active radiation products for different canopy radiation transfer regimes: methodology ...
Treesearch
... and is responsible for developing the leaf area index (LAI) and fraction of absorbed photosynthetically active radiation (FPAR) products. ...
NASA Website
The quantity of radiation potentially available for photosynthesis that is captured by the crop is best described as absorbed photosynthetically active radiation (PAR). Absorbed PAR (APAR) is the difference between descending and ascending fluxes. The fou...
National Technical Information Service (NTIS)
... understanding of the photosynthetic productivity of a crop (Sinclair and ... 17 photosynthetically active radiation (PAR) absorbed by the canopy. More ...
DTIC Science & Technology
Most models of crop growth and yield require an estimate of canopy leaf area index (LAI) or absorption of radiation. Relationships between photosynthetically active radiation (PAR) absorbed by corn canopies and the spectral reflectance of the canopies wer...
MODIS FPAR/LAI is the Fraction of Absorbed Photosynthetically Active radiation that a plant canopy absorbs for photosynthesis and growth in the 0.4 0.7nm ...
Exploring Photosynthesis with NASA Remote Sensing Data, Shenandoah National ... stands for the Fraction of Absorbed Photosynthetically Active Radiation. ...
... TCARI) The spectral index TCARI is used in remote sensing to estimate the absorbed photosynthetically active radiation. ...
Estimating the fraction of absorbed photosynthetically active radiation (APAR) at FIFE with airborne bidirectional spectral reflectance data. J. Geophys. ...
Spectral reflectance data of corn and soybeans were highly correlated with leaf area index and absorbed photosynthetically active radiation (PAR). Above ground phytomass and grain yields were predicted with absorbed PAR cumulated during the growing season...
the other index (NDVI) being more related to absorbed photosynthetically active radiation (APAR) and %green parameters such as leaf area index (LAI), fraction of absorbed photosynthetic active radiation (fPAR), net and temporal patterns of vegetation ...
E-print Network
In photosynthesis, the number of photons absorbed in the 400 700 nm spectral range is estimated and is referred to as photosynthetic active radiation (PAR). ...
indices have been used to estimate absorbed photosynthetically active radiation (PAR), providing time photosynthetically active radiation (PAR) from sunrise to noon to obtain assimilation responses to irradiation (i Meteorology 100 (2000) 35�48 Fig. 5. Net canopy ...
The mean annual quantities of photosynthetically active radiation (PAR) absorbed during various stage of regeneration of a tropical rain forest in the upper Rio Negro region of Colombia and Venezuela were estimated for the intervals between clearcut and 1...
The fraction, of photosynthetically active radiation absorbed by vegetation, F sub ipar, is an important requirement for estimating vegetation biomass productivity and related quantities. This was an integral part of a large international effort; the Firs...
Dec 27, 2001... sum longitude: sum period: sum 0 -9999.000000 -9999.000000 Average of Fractional absorbed Photosynthetically Active Radiation (FPAR). ...
Feb 7, 2010... Float32 missing_value -9999.000000; String long_name "Average of Fractional absorbed Photosynthetically Active Radiation (FPAR). ...
... and normalized difference vegetation indices and the biophysical parameters fraction of absorbed photosynthetically active radiation (APAR) and ...
Research product elements: Leaf area index. Fractional absorbed. PRELIMINARY. DESIGN REV!EW. 5124193 photosynthetically active radiation. 21. SCIENCE. DIN[:ll .
NDVI as an Indicator of Drought. Satellite remote sensors can quantify what fraction of the photosynthetically active radiation is absorbed by vegetation. ...
Moreover, BigFoot maps land cover, LAI, fraction absorbed photosynthetic active ... Finally, BigFoot takes important steps to enhance the goals of GTOS. ...
Jun 2, 2000 ... Today's image is a MODIS data product called "Fraction of Photosynthetically Active Radiation," which is a measure of the proportion of the ...
Ecosystem Characterization Products. " Spectral Vegetation Indices. " Fraction Absorbed Photosynthetically-Active Radiation (fAPAR). " Leaf Area Index (LAI) ...
... available field information into broad categories representing different radiative transfer regimes. This strategy greatly helps the interpretation of ... ...
NBII National Biological Information Infrastructure
Providing an indication of overall landscape greenness which can linked with estimates of Absorbed Photosynthetic Active Radiation (APAR) to provide good ...
Leaves of the dominant grass species of the ISCLP FIFE site reflect and transmit radiation in a like
NASA Technical Reports Server (NTRS)
Jul 7, 2011 ... Estimating the fraction of absorbed photosynthetically active ... 10.1029/ 95JD01045 � Cahalan R.F., D. Silberstein, and J. B. Snider (1995). ...
Photosynthetically Active Radiation absorbed by vegetation (FPAR) are 1-km at- launch products pro- vided on a daily and 8-day basis. LAI defines an im- ...
... the spatial variability and temporal dynamics of the photosynthetic active radiation absorbed (APAR) by the canopy, a descriptor of ... radiation. Plains intercepted 37% and hills 14% less photosynthetic ...
photosystems absorbing photons, and PAR is the photosynthetic active radiation (Genty et al. 1989). Beer et al, the photosynthetic re- sponses of zooxanthellae in the coenosarc and the polyp tissue of Acropora nobilis were damage to photosystem II. Introduction Heterogeneous distribution of ...
images against changes in the fraction of incident photosynthetically active radiation that is absorbed photosynthetically active radiation that is absorbed by the canopy (fAPAR), and a broadband normalized difference and sky above the ROI and understory or forest floor ...
radiation (PAR) as well as between Chl and PAR absorbed by photosynthetically active ("green") vegetation of absorbed photosynthetically active radiation in crops. Geophys. Res. Lett. 32:L17403. doi:10.1029/2005GL and utilization of solar radiation and, consequently, drive ...
The primary motivation of this research activity is to document the feasibility of deriving global fields of LAI (leaf area index) and FPAR (fraction of photosynthetically active radiation absorbed by vegetation) from atmosphere corrected ESA (European Sp...
One of the objectives of the Oregon Transect Ecosystem Research (OTTER) project is the remotely sensed determination of the seasonal variation of leaf area index (LAI) and absorbed photosynthetically active radiation (APAR). These measurements are require...
Normalized difference vegetation index (NDVI) data, acquired at two-meter resolution by an airborne ADAR System 5500, were compared with fraction of photosynthetically active radiation (FPAR) absorbed by commercial vineyards in Napa Valley, California. An...
Jun 16, 2011... phenology from the advanced very high resolution radiometer (AVHRR) as a means to ... The fraction absorbed of photosynthetically active radiation (FPAR) by ... The periods of highest detection frequency were 1987-1989, ...
A procedure to estimate biomass production of a crop from the proportion of photosynthetic active energy (PAR) absorbed by the canopy (Sigma i) is outlined. It is shown that Sigma i is functionally linked to the radiometric response of the crop, and an an...
... DHR for near-infrared band (DHR-NIR), fractional absorbed photosynthetically active radiation (FPAR), DHR-based normalized difference vegetation index ...
The objective of our effort was to collect and archive data on LAI (leaf area index) and FPAR (Fraction of Photosynthetically active Radiation absorbed by vegetation) at the EOS Core validation sites as well as to validate and evaluate global fields of LA...
G. Asrar, M. Fuchs, E. T. Kanemasu, and J. L. Hatfield, ''Estimating absorbed photosynthetic active radiation and leaf area index from spectral reflectance ...
The mean annual quantities of photosynthetically active radiation (PAR) absorbed during various stage of regeneration of a tropical rain forest in the upper Rio Negro region of Colombia and Venezuela were estimated for the intervals between clearcut and 1, 3, 10, 20, 35, 60, 80, and 200 years of growth. The forest phytomass and ...
Energy Citations Database
MODIS observations also allow scientists to track two vital signs of Earths vegetation. At Boston University, a team of researchers is using MODIS data to create global estimates of the green leaf area of Earths vegetation and how much sunlight the leaves are absorbing. Called LAI, for Leaf Area Index, and FPAR, for Fraction of absorbed ...
NSDL National Science Digital Library
Abstract: Primary productivity and photosynthetic activity measured with 13C ... BIOSPHERE >VEGETATION >PHOTOSYNTHETICALLY ACTIVE RADIATION [Definition] ...
forests are optically darker than other vegetation types, allowing them to absorb more solar radiation, the quantum flux Q, of photosynthetically active radiation (PAR) absorbed by canopy leaves, and the quantum speed [Chanzy and Bruckler, 1993], although the latter tends to be very low at the forest floor [Wilson
Levels of polypeptides participating in the photosynthetic light and dark reactions have been measured during fruit ripening in tomato. Photosynthetic proteins were identified by Western blot analysis with heterologous antibodies. The concentrations of proteins of photosystem (PS) I (14 kilodaltons), of PSII (47-kilodalton reaction center protein, ...
PubMed Central
Sunlight damages photosynthetic machinery, primarily photosystem II (PSII), and causes photoinhibition that can limit plant photosynthetic activity, growth and productivity. The extent of photoinhibition is associated with a balance between the rate of photodamage and its repair. Recent studies have shown that light absorption by the ...
PubMed
The goals of this study are (a) to investigate relationships between light use efficiency (LUE) and crop biophysical characteristics: chlorophyll content, green leaf area index and total leaf area index; (b) to find way to assess remotely gross primary production and LUE. We studied incident light use efficiency, efficiency of use of the total absorbed light, and efficiency ...
NASA Astrophysics Data System (ADS)
Relationship. Between Measures of Absorbed and Reflected. Radiation and the Photosynthetic. Capacity of Boreal Forest Canopies and Understories. 2.3 Contact ...
Net photosynthesis, growth, and ultraviolet (uv) radiation absorbance were determined for the first leaf of Cucurbita pepo L. exposed to two levels of uv-B irradiation and a uv-B radiation-free control treatment. Absorbance by extracted flavonoid pigments and other uv-B radiation-absorbing compounds from the first leaves increased with ...
Net photosynthesis, growth, and ultraviolet (UV) radiation absorbance were determined for the first leaf of Cucurbita pepo L. exposed to two levels of UV-B irradiation and a UV-B radiation-free control treatment. Absorbance by extracted flavonoid pigments and other UV-B radiation-absorbing compounds from the first leaves increased with ...
By using a portable photosynthetic system (CIRAS-2), this paper studied the photosynthetic characters of 3-year-old Cotinus coggygria var. cinerea under effects of different soil water regime (enough supply, light stress, medium stress, and heavy stress) and light intensity. Soil water regime had significant effects on the ...
A useful parameter to estimate terrestrial primary productivity, that can be sensed from space, is the daily averaged fraction of Photosynthetically Available Radiation (PAR) absorbed by plants. To evaluate this parameter, investigators have relied on the...
Primary productivity and photosynthetic activity, UM0809 ... OCEANS > OCEAN OPTICS > PHOTOSYNTHETICALLY ACTIVE RADIATION � Parameter Definition ...
Abstract: Primary productivity and photosynthetic activity measured with 13C ... BIOSPHERE > VEGETATION > PHOTOSYNTHETICALLY ACTIVE RADIATION � Parameter ...
... wavelength band 400�700 nm. This produces a climatology of photosynthetically active radiation for each month of ... at high southern latitudes and to produce a climatology of photosynthetically active ra...
Contents: Problems of works on the study of photosynthetic activity of plants as a factor of productivity; The bases of the quantitative theory of the photosynthetic activity of sowings; The role of solar radiation in the photosynthetic activity of crops;...
Continuous depletion of the stratospheric ozone layer has resulted in an increase in ultraviolet-B (UV-B; 280-315 nm) radiation on the earth's surface which inhibits photochemical and photobiological processes. However, certain photosynthetic organisms have evolved mechanisms to counteract the toxicity of ultraviolet or high photosynthetically ...
Gross primary productivity (GPP) often is estimated at regional scales by multiplying the amount of photosynthetically active radiation (PAR) absorbed by the plant canopy (PARa) by light-use efficiency (eg; GPP/PARa). Mass flux techniques are being used to calculate eg. Flux-based estimates of eg ...
Technology Transfer Automated Retrieval System (TEKTRAN)
Gross primary productivity (GPP) often is estimated at regional and global scales by multiplying the amount of photosynthetically active radiation (PAR) absorbed by the plant canopy (PARa) by a light-use efficiency (eg) which is modeled as a function of air temperature (Ta) and other environmental c...
Chlorophylls absorb photosynthetically active radiation and thus function as vital pigments for photosynthesis, which makes leaf chlorophyll content (Cab) useful for monitoring vegetation productivity and an important indicator of the overall plant physiological condition. This study investigates th...
: Artemisia zum, A. mon- dahurica, Ther- frigida, Leonto- golicum mopsis dahurica, podium ochro leu- shrubs: Festuca plant ica, S. glareosa lovii, Clistogenes lenensis, Koelaria speciesb forbs: Artemisia squarrosa: Caragan a Oxytropis spp. crum , Oxytropis spp., Artemisia shrubs: Caragana spp. spp. spp. Typical dry 50
The photoactivity of active bacteriochlorophyll and the absorption spectrum of bacteriochlorophyll absorbing at 800 nm are temporarily lost at low pH but partially regenerated by increasing the pH within a certain time limit. This pH-induced modification ...
In this activity students measure photosynthetically available radiation (PAR). Students determine the solar input by calculating the amount of heat absorbed by a known mass of water exposed to a known cross-sectional area of sunlight. Students discuss the variables influencing their measurements, the reasons why solar input might ...
The problem of how the scale, or spatial resolution, of reflectance data impacts retrievals of vegetation leaf area index (LAI) and fraction absorbed photosynthetically active radiation (PAR) has been investigated. We define the goal of scaling as the pro...
of photosynthetically active radiation absorbed by vegetation (FPAR). The algorithm consists of a main procedure{page } MODIS SEMI-ANNUAL REPORT: JUN/30/97 - DEC/31/97 Radiative Transfer Based Synergistic MODIS a radiative transfer based synergistic algorithm for estima- tion of global leaf area index (LAI) and fraction
of photosynthetically active radiation absorbed by vegetation (FPAR). The algorithm consists of a main procedureMODIS QUARTERLY REPORT: JUN/30/97 - SEP/30/97 Radiative Transfer Based Synergistic MODIS a radiative transfer based synergistic algorithm for estimation of global leaf area index (LAI) and fraction
) and fraction of photosynthetic active radiation absorbed by vegetation (FPAR) from atmospherically correctedMODIS QUARTERLY REPORT: JAN/01/97 --- MAR/31/97 Radiative Transfer Based Synergistic MODIS a radiative transfer based synergistic algorithm for the estimation of global leaf area index (LAI
) and fraction of absorbed photosynthetically active radiation (e.g. DeFries et al., 2000; Pauwels & Wood, 2000 source was forest floor evaporation from the upland stands. The second source was forest wetland soil to wet the forest floor. The soil surface evaporation fluxes were determined using a soil resistance
Determinations of the rate of photosynthesis were made in barley and maize leaves treated with INH, DNP, 2,4-D or CMU. 1 ppm of the chemicals in nutritive solution was absorbed by roots during 24 or 48 hours in both dark and light conditions. After this p...
The objective of this study was to examine to test the relationship between net ecosystem fluxes and absorbed photosynthetically active radiation (PAR) as a method of estimating production at regional scales from field-scale data. The Soil Moisture Experiment 2005 was conducted in Walnut Creek Water...
area/m2 ground area) and absorbed photosynthetically active radiation (Asrar et al. 1984, Wiegand et al. ... than 3 m2 leaf area per m2 of vineyard floor (between- row spaces ..... Agricultural and Forest Meteorology 44,. 245260. Nemani, R.R. ...
