As an experiment, I thought I’d try posting some science instead of nonsense or mountains. From Nurture (Peter van der Sleen et al., Nature Geoscience 8, 24–28 (2015) doi:10.1038/ngeo2313):
The biomass of undisturbed tropical forests has likely increased in the past few decades1, 2, probably as a result of accelerated tree growth. Higher CO2 levels are expected to raise plant photosynthetic rates3 and enhance water-use efficiency4, that is, the ratio of carbon assimilation through photosynthesis to water loss through transpiration. However, there is no evidence that these physiological responses do indeed stimulate tree growth in tropical forests. Here we present measurements of stable carbon isotopes and growth rings in the wood of 1,100 trees from Bolivia, Cameroon and Thailand. Measurements of carbon isotope fractions in the wood indicate that intrinsic water-use efficiency in both understorey and canopy trees increased by 30–35% over the past 150 years as atmospheric CO2 concentrations increased. However, we found no evidence for the suggested concurrent acceleration of individual tree growth when analysing the width of growth rings. We conclude that the widespread assumption of a CO2-induced stimulation of tropical tree growth may not be valid.
This is a partial antidote to the CO2-is-plant-food people, but also to the ZOMG-crop-yields-are-falling people, since increased water efficiency is good. Mind you, not all plants are exactly the same, so it may not apply to the crops we care about in the circumstances we care about. Biology is complex, no?
from ScienceBlogs http://ift.tt/1Dc3QIH
As an experiment, I thought I’d try posting some science instead of nonsense or mountains. From Nurture (Peter van der Sleen et al., Nature Geoscience 8, 24–28 (2015) doi:10.1038/ngeo2313):
The biomass of undisturbed tropical forests has likely increased in the past few decades1, 2, probably as a result of accelerated tree growth. Higher CO2 levels are expected to raise plant photosynthetic rates3 and enhance water-use efficiency4, that is, the ratio of carbon assimilation through photosynthesis to water loss through transpiration. However, there is no evidence that these physiological responses do indeed stimulate tree growth in tropical forests. Here we present measurements of stable carbon isotopes and growth rings in the wood of 1,100 trees from Bolivia, Cameroon and Thailand. Measurements of carbon isotope fractions in the wood indicate that intrinsic water-use efficiency in both understorey and canopy trees increased by 30–35% over the past 150 years as atmospheric CO2 concentrations increased. However, we found no evidence for the suggested concurrent acceleration of individual tree growth when analysing the width of growth rings. We conclude that the widespread assumption of a CO2-induced stimulation of tropical tree growth may not be valid.
This is a partial antidote to the CO2-is-plant-food people, but also to the ZOMG-crop-yields-are-falling people, since increased water efficiency is good. Mind you, not all plants are exactly the same, so it may not apply to the crops we care about in the circumstances we care about. Biology is complex, no?
from ScienceBlogs http://ift.tt/1Dc3QIH
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