Relationships between daytime carbon dioxide uptake and absorbed photosynthetically active radiation for three different mountain/plains ecosystems
نویسندگان
چکیده
منابع مشابه
Response of Canopy Solar-Induced Chlorophyll Fluorescence to the Absorbed Photosynthetically Active Radiation Absorbed by Chlorophyll
Solar-induced chlorophyll fluorescence (SIF), which can be used as a novel proxy for estimating gross primary production (GPP), can be effectively retrieved using ground-based, airborne and satellite measurements. Absorbed photosynthetically active radiation (APAR) is the key bridge linking SIF and GPP. Remotely sensed SIF at the canopy level (SIFcanopy) is only a part of the total SIF emission...
متن کاملUsing hyperspectral vegetation indices to estimate the fraction of photosynthetically active radiation absorbed by corn canopies
The fraction of photosynthetically active radiation (FPAR) absorbed by vegetation – a key parameter in crop biomass and yields as well as net primary productivity models – is critical to guiding crop management activities. However, accurate and reliable estimation of FPAR is often hindered by a paucity of good field-based spectral data, especially for corn crops. Here, we investigate the relati...
متن کاملfAPAR (fraction of Absorbed Photosynthetically Active Radiation) estimates at various scale
This paper reviews the several methods available for estimating the fAPAR, both at local and large scale. The fAPAR definition is first discussed with regards to the directionality of the incident radiation. Then, the several techniques to estimate fAPAR from local ground measurements are reviewed with emphasis on the sampling strategy. We then describe methodologies to upscale fAPAR measuremen...
متن کاملNew developments in the remote estimation of the fraction of absorbed photosynthetically active radiation in crops
[1] The fraction of absorbed photosynthetically active radiation, fAPAR, is an important biophysical characteristic in models of gas exchange between the terrestrial boundary layer and the atmosphere, as well as in the analysis of vegetation productivity. Synoptic estimation of fAPAR has been performed by using NDVI as a linear proxy of fAPAR, despite the saturation of NDVI at fAPAR beyond 0.7....
متن کاملPhotosynthetically active radiation: measurements and modelling
Photosynthetically-active radiation is a necessary input in applications dealing with plant physiology, biomass production and natural illumination in greenhouses. Unfortunately, a worldwide routine network for the measurement of photosynthetically-active radiation is not yet established and it is often calculated as a constant ratio of the broadband solar radiation. This ratio is affected by m...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Geophysical Research
سال: 2002
ISSN: 0148-0227
DOI: 10.1029/2001jd001181