Location: Southwest Watershed ResearchTitle: Global and time-resolved monitoring of crop photosynthesis with chlorophyll fluorescence Author
|Moran, Mary - Susan|
|Ponce Campos, G.|
Submitted to: Proceedings of the National Academy of Sciences
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/24/2014
Publication Date: 3/25/2014
Citation: Gaunter, L., Zhang, Y., Jung, M., Joiner, J., Voight, M., Berry, J., Frankenberg, C., Huete, A., Zarco-Trejada, P., Lee, J., Moran, M.S., Ponce Campos, G., Beer, C., Camps-Vall, G., Buchmann, N., Gianelle, D., Klumpp, K., Cescatti, A., Baker, J.M., Griggis, T. 2014. Global and time-resolved monitoring of crop photosynthesis with chlorophyll fluorescence. Proceedings of the National Academy of Sciences. 111(14):E1327-E1333. doi: 10.1073/pnas.1320008111. Interpretive Summary: With increasing food demand, it is critical to know the status of global food supply. A new satellite has just been launched to make worldwide measurements of cropland productivity. Based on these measurements, we found that the US Western Corn Belt is producing at a rate 50–75% higher than previously predicted, and in fact, is the highest producing ecosystem on the planet. Our results contribute to the understanding of the global carbon cycle in general, and to food security in particular.
Technical Abstract: Global monitoring of agricultural productivity is critical in a world under a continuous increase of food demand. Here we have used new spaceborne retrievals of chlorophyll fluorescence, an emission quantity intrinsically linked to photosynthesis, to derive spatially explicit photosynthetic uptake rates of the crop belts worldwide. Our estimates of annual crop primary productivity are substantially higher (50–75%) than results from carbon cycle models in some large agricultural regions, such as the US Western Corn Belt, where we detect the highest fluorescence of all ecosystems on the planet. These findings are supported by an independent validation against yield statistics. Our results highlight the need for observational inputs to quantify photosynthetic activity, particularly over highly cultivated land, with implications on the global carbon cycle and food security.