*Quantifying climate mitigation benefits of biosphere protection or restoration requires accurate assessment of forest above-ground biomass (AGB). This is usually estimated using tree size-to-mass allometric models calibrated with harvested biomass data.*
*Using three-dimensional laser measurements across the full range of tree size and shape in a typical UK temperate forest, we show that its AGB is 409.9 t ha−1, 1.77 times more than current allometric model estimates. This discrepancy arises partly from the bias towards small trees in allometric model calibration: 50% of AGB in this forest was in less than 7% of the largest trees (stem diameter > 53.1 cm), all larger than the trees used to calibrate the widely used allometric model.*
*We present new empirical evidence that the fundamental assumption of tree size-to-mass scale-invariance is not well-justified for this kind of forest. This leads to substantial biases in current biomass estimates of broadleaf forests, not just in the UK, but elsewhere where the same or similar allometric models are applied, due to overdependence on non-representative calibration data, and the departure of observed tree size-to-mass from simple size-invariant relationships.*
*We suggest that testing the underlying assumptions of allometric models more generally is an urgent priority as this has wider implications for climate mitigation through carbon sequestration. Forests currently act as a carbon sink in the UK. However, the anticipated increase in forest disturbances makes the trajectory and magnitude of this terrestrial carbon sink uncertain. We make recommendations for prioritizing measurements with better characterized uncertainty to address this issue.*
This is great news. But let’s not use it as an excuse not to plant more, especially in cities and high traffic areas. And I say this next bit as someone who cares greatly for the environment. I don’t care about CO2 levels. What we ought to be focusing on is soil quality, particulates absorption, and biodiversity. Focusing on these things would be better as CO2 absorption would just be a consequence of it. Where focusing on CO2 doesn’t necessarily mean those things improve.
This is great news, but it also means the reverse is true – when trees are cut down we lose 1.77x more too (assuming they are burnt or destroyed in other ways to make way for roads, fields etc. If they are turned into furniture I guess it’s moot)
This will be the carbon the government will next remove.
Ancient woodland should get much stricter protection laws then. We cannot lose any more than we already have and the likes of HS2 are a threat to it. We need ancient woodland and it is irreplaceable in our lifetimes, as well as our grandchildren’s lifetimes. If the carbon capture potential is much greater then so do our environmental protection acts.
Its great to see how accurate “green science” actually is (sarcasm)
They measured the charge of the electron in 1908 but its ok to say CO2=bad based on junk science. Close down all the fossil fuel power plants and charge us double.
Tory government looking at ways to chop them down and extract the carbon TODAY.
Lidar? I don’t have time to read the whole article, but the use of Lidar suggests to me this is a correction of the assumed tree sizes in woodlands, the correction being around 1.77x more than before.
It’s not claiming that any chosen tree holds 1.77x more carbon than previously calculated, is it?
If so, it doesn’t mean that trees are more efficient at capturing carbon than previously thought. It means that there is more carbon being captured by exiting forests and woodlands.
This is actually bad news. It means that our calculations of how much woodlands help in keeping carbon out of the atmosphere was over-estimated by 77%. We actually need 77% more tree mass to keep the CO2 to the same levels as first thought.
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https://besjournals.onlinelibrary.wiley.com/doi/10.1002/2688-8319.12197
Abstract
*Quantifying climate mitigation benefits of biosphere protection or restoration requires accurate assessment of forest above-ground biomass (AGB). This is usually estimated using tree size-to-mass allometric models calibrated with harvested biomass data.*
*Using three-dimensional laser measurements across the full range of tree size and shape in a typical UK temperate forest, we show that its AGB is 409.9 t ha−1, 1.77 times more than current allometric model estimates. This discrepancy arises partly from the bias towards small trees in allometric model calibration: 50% of AGB in this forest was in less than 7% of the largest trees (stem diameter > 53.1 cm), all larger than the trees used to calibrate the widely used allometric model.*
*We present new empirical evidence that the fundamental assumption of tree size-to-mass scale-invariance is not well-justified for this kind of forest. This leads to substantial biases in current biomass estimates of broadleaf forests, not just in the UK, but elsewhere where the same or similar allometric models are applied, due to overdependence on non-representative calibration data, and the departure of observed tree size-to-mass from simple size-invariant relationships.*
*We suggest that testing the underlying assumptions of allometric models more generally is an urgent priority as this has wider implications for climate mitigation through carbon sequestration. Forests currently act as a carbon sink in the UK. However, the anticipated increase in forest disturbances makes the trajectory and magnitude of this terrestrial carbon sink uncertain. We make recommendations for prioritizing measurements with better characterized uncertainty to address this issue.*
This is great news. But let’s not use it as an excuse not to plant more, especially in cities and high traffic areas. And I say this next bit as someone who cares greatly for the environment. I don’t care about CO2 levels. What we ought to be focusing on is soil quality, particulates absorption, and biodiversity. Focusing on these things would be better as CO2 absorption would just be a consequence of it. Where focusing on CO2 doesn’t necessarily mean those things improve.
This is great news, but it also means the reverse is true – when trees are cut down we lose 1.77x more too (assuming they are burnt or destroyed in other ways to make way for roads, fields etc. If they are turned into furniture I guess it’s moot)
This will be the carbon the government will next remove.
Ancient woodland should get much stricter protection laws then. We cannot lose any more than we already have and the likes of HS2 are a threat to it. We need ancient woodland and it is irreplaceable in our lifetimes, as well as our grandchildren’s lifetimes. If the carbon capture potential is much greater then so do our environmental protection acts.
Its great to see how accurate “green science” actually is (sarcasm)
They measured the charge of the electron in 1908 but its ok to say CO2=bad based on junk science. Close down all the fossil fuel power plants and charge us double.
Tory government looking at ways to chop them down and extract the carbon TODAY.
Lidar? I don’t have time to read the whole article, but the use of Lidar suggests to me this is a correction of the assumed tree sizes in woodlands, the correction being around 1.77x more than before.
It’s not claiming that any chosen tree holds 1.77x more carbon than previously calculated, is it?
If so, it doesn’t mean that trees are more efficient at capturing carbon than previously thought. It means that there is more carbon being captured by exiting forests and woodlands.
This is actually bad news. It means that our calculations of how much woodlands help in keeping carbon out of the atmosphere was over-estimated by 77%. We actually need 77% more tree mass to keep the CO2 to the same levels as first thought.