@article {KNZ001119,
	title = {Photosynthetic traits in C3 and C4 grassland species in mesocosm and field environments},
	journal = {Environmental and Experimental Botany},
	volume = {60},
	year = {2007},
	pages = {412 -420},
	abstract = {The North American tallgrass prairie is composed of a diverse mix of C3 and C4 plant species that are subject to multiple resource limitations. C4 grasses dominate this ecosystem, purportedly due to greater photosynthetic capacity and resource-use efficiency associated with C4 photosynthesis. We tested the hypothesis that intrinsic physiological differences between C3 and C4 species are consistent with C4 grass dominance by comparing leaf gas exchange and chlorophyll fluorescence variables for seven C4 and C3 herbaceous species (legumes and non-legumes) in two different settings: experimental mesocosms and natural grassland sites. In the mesocosms, C4 grasses had higher photosynthetic rates, water potentials and water-use efficiency than the C3 species. These differences were absent in the field, where photosynthetic rates declined similarly among non-leguminous species. Thus, intrinsic photosynthetic advantages for C4 species measured in resource-rich mesocosms could not explain the dominance of C4 species in the field. Instead, C4 dominance in this ecosystem may depend more on the ability of the grasses to grow rapidly when resources are plentiful and to tolerate multiple limitations when resources are scarce.},
	keywords = {LTER-KNZ, A:Ci curves, C3, C4, Chlorophyll fluorescence, gas exchange, Konza, tallgrass prairie},
	doi = {10.1016/j.envexpbot.2006.12.012},
	author = {Jesse B. Nippert and Fay, P.A. and Alan K. Knapp}
}
@article {KNZ00486,
	title = {Stomatal and photosynthetic responses to variable light in sorghum, soybeans and eastern gammagrass},
	journal = {Physiologia Plantarum},
	volume = {94},
	year = {1995},
	pages = {613 -620},
	abstract = {We studied photosynthetic and stomatal responses of grain sorghum (Sorghum bicolor [L.] Moench cv. Pioneer 8500), soybean (Glycine max L. cv. Flyer) and eastern gamagrass (Tripsacum dactyloides L.) during experimental sun and shade periods simulating summer cloud cover. Leaf gas exchange measurements of field plants showed that short-term (5 min) shading of leaves to 300{\textendash}400 μmol m-2 s-1 photosynthetic photon flux density reduced photosynthesis, leaf temperature, stomatal conductance, transpiration and water use efficiency and increased intercellular CO2 partial pressure. In all species, photosynthetic recovery was delayed when leaves were reilluminated, apparently by stomatal closure. The strongest stomatal response was in soybean. Photosynthetic recovery was studied further with soybeans grown indoors (maximum photosynthetic photon flux density 1 200 μmol m-2 s-1). Plants grown indoors had responses to shade similar to those of field plants, except for brief nonstomatal limitation immediately after reillumination. These responses indicated the importance of the light environment during leaf development on assimilation responses to variable light, and suggested different limitations on carbon assimilation in different parts of the soybean canopy. Photosynthetic oxygen evolution recovered immediately upon reillumination, indicating that the light reactions did not limit soybean photosynthetic recovery. While shade periods caused stomatal closure and reduced carbon gain and water loss in all species, the consequences for carbon gain/water loss were greatest in soybean. The occurrence of stomatal closure in all three species may arise from their shared phenologies and herbaceous growth forms.},
	keywords = {LTER-KNZ, A:Ci curves, eastern gamagrass, Glycine max, induction, light, oxygen evolution, photosynthesis, sorghum, Sorghum bicolor, soybean, Stomatal Conductance, Tripsacum dactyloides, Water use efficiency},
	doi = {10.1111/j.1399-3054.1995.tb00975.x},
	author = {Fay, P.A. and Alan K. Knapp}
}
