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Samuel L. O. Quin - One of the best experts on this subject based on the ideXlab platform.
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calluna vulgaris dominated upland heathland sequesters more co2 annually than grass dominated upland heathland
Science of The Total Environment, 2015Co-Authors: Rebekka R E Artz, Samuel L. O. Quin, Andrew Coupar, Sarah J. WoodinAbstract:Abstract It has been shown in many habitats worldwide, that a shift in vegetation composition between woody shrub and graminoid dominance can influence carbon (C) cycling. Due to land management practices and environmental change, UK upland heath vegetation has historically undergone shifts in dominance from the woody dwarf shrub Calluna vulgaris (Calluna) to species poor graminoid swards. The consequences of this for C sequestration are unknown. We compared annual net ecosystem exchange (NEE) of carbon dioxide (CO2) between building phase Calluna- and grass-dominated communities within three upland heaths in Scotland, measuring c. monthly over a year. Light and temperature response curves were generated, and the parameters derived were applied to continuous light and temperature data to extrapolate CO2 fluxes over the full year and generate estimates of annual CO2 sequestration for each vegetation type. Grass-dominated communities had higher ecosystem respiration rates than Calluna-dominated communities, attributed to Graminoids having greater metabolic demands and producing more labile litter which decomposes readily. Both communities had similar gross primary productivity over the year; the net result being higher NEE within the Calluna-dominated than the grass-dominated community (− 2.36 ± 0.23 and − 1.78 ± 0.18 μmol CO2 m− 2 s− 1 respectively). Modelled CO2 fluxes over a year showed both communities to be CO2 sinks. The Calluna-dominated community sequesters − 3.45 ± 0.96 t C ha− 1 yr− 1, double that sequestered by the grass-dominated community at 1.61 ± 0.57 t C ha− 1 yr− 1. Potential rate of C sequestration by upland heath is comparable to that of woodland and the increase in total sequestration that could be gained from habitat restoration may equate to c. 60% of the annual UK C sink attributed to forest land management. National C sequestration by heathlands is also more than double that by peatlands. Management of graminoid-dominated upland heath should promote Calluna re-establishment, thus providing a C benefit in addition to benefits to biodiversity, grazing and sporting interests.
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Restoration of upland heath from a graminoid- to a Calluna vulgaris-dominated community provides a carbon benefit
Agriculture Ecosystems & Environment, 2014Co-Authors: Samuel L. O. Quin, Rebekka R E Artz, Andrew Coupar, Nick A. Littlewood, Sarah J. WoodinAbstract:Abstract Restoration of degraded upland habitats has the potential to improve carbon (C) sequestration, thus helping offset national greenhouse gas emissions. Here we test the hypotheses (1) that degraded upland heath, dominated by Graminoids, will have higher rates of soil respiration and smaller C pools than long established, Calluna vulgaris (Calluna) dominated upland heath, and (2) that restoration of degraded heath will increase carbon pools and decrease soil respiration towards that of “target” Calluna heath. Soil respiration and total and recalcitrant C stocks in above- and below-ground vegetation and in the topsoil (to a depth of 15 cm) were estimated at seven upland sites in Northern England and Scotland. Three vegetation types were present at each site; graminoid-dominated upland heath that had formerly been Calluna-dominated upland heath (“degraded”); restored upland heath, converted from graminoid to dwarf shrub dominance (“restored”) and long-established, Calluna-dominated (“target”) upland heath. Soil respiration did not differ between the three vegetation types. Degraded areas contained a larger C pool in the vegetation but a lower soil C pool and total C stock than target areas. Restored areas held similar vegetation, soil and total C stocks to those of target areas. All areas had similar pools of recalcitrant C in their vegetation, but both target and restored areas contained more recalcitrant C in the soil, and in total, than degraded areas. The C benefit of restoration varied between sites, partly due to the abundance of Molinia caerulea in degraded vegetation at some sites, but the overall C benefit of restoring Calluna-dominated upland heath was 0.60 ± 0.70 t C ha−1 yr−1 since restoration. Restoration also increased the size of the recalcitrant C pool, which will increase C residence time and hence soil C accumulation in the longer term. Thus restoration of degraded areas is a valid option for promoting C sequestration within upland heath.
Sarah J. Woodin - One of the best experts on this subject based on the ideXlab platform.
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calluna vulgaris dominated upland heathland sequesters more co2 annually than grass dominated upland heathland
Science of The Total Environment, 2015Co-Authors: Rebekka R E Artz, Samuel L. O. Quin, Andrew Coupar, Sarah J. WoodinAbstract:Abstract It has been shown in many habitats worldwide, that a shift in vegetation composition between woody shrub and graminoid dominance can influence carbon (C) cycling. Due to land management practices and environmental change, UK upland heath vegetation has historically undergone shifts in dominance from the woody dwarf shrub Calluna vulgaris (Calluna) to species poor graminoid swards. The consequences of this for C sequestration are unknown. We compared annual net ecosystem exchange (NEE) of carbon dioxide (CO2) between building phase Calluna- and grass-dominated communities within three upland heaths in Scotland, measuring c. monthly over a year. Light and temperature response curves were generated, and the parameters derived were applied to continuous light and temperature data to extrapolate CO2 fluxes over the full year and generate estimates of annual CO2 sequestration for each vegetation type. Grass-dominated communities had higher ecosystem respiration rates than Calluna-dominated communities, attributed to Graminoids having greater metabolic demands and producing more labile litter which decomposes readily. Both communities had similar gross primary productivity over the year; the net result being higher NEE within the Calluna-dominated than the grass-dominated community (− 2.36 ± 0.23 and − 1.78 ± 0.18 μmol CO2 m− 2 s− 1 respectively). Modelled CO2 fluxes over a year showed both communities to be CO2 sinks. The Calluna-dominated community sequesters − 3.45 ± 0.96 t C ha− 1 yr− 1, double that sequestered by the grass-dominated community at 1.61 ± 0.57 t C ha− 1 yr− 1. Potential rate of C sequestration by upland heath is comparable to that of woodland and the increase in total sequestration that could be gained from habitat restoration may equate to c. 60% of the annual UK C sink attributed to forest land management. National C sequestration by heathlands is also more than double that by peatlands. Management of graminoid-dominated upland heath should promote Calluna re-establishment, thus providing a C benefit in addition to benefits to biodiversity, grazing and sporting interests.
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Restoration of upland heath from a graminoid- to a Calluna vulgaris-dominated community provides a carbon benefit
Agriculture Ecosystems & Environment, 2014Co-Authors: Samuel L. O. Quin, Rebekka R E Artz, Andrew Coupar, Nick A. Littlewood, Sarah J. WoodinAbstract:Abstract Restoration of degraded upland habitats has the potential to improve carbon (C) sequestration, thus helping offset national greenhouse gas emissions. Here we test the hypotheses (1) that degraded upland heath, dominated by Graminoids, will have higher rates of soil respiration and smaller C pools than long established, Calluna vulgaris (Calluna) dominated upland heath, and (2) that restoration of degraded heath will increase carbon pools and decrease soil respiration towards that of “target” Calluna heath. Soil respiration and total and recalcitrant C stocks in above- and below-ground vegetation and in the topsoil (to a depth of 15 cm) were estimated at seven upland sites in Northern England and Scotland. Three vegetation types were present at each site; graminoid-dominated upland heath that had formerly been Calluna-dominated upland heath (“degraded”); restored upland heath, converted from graminoid to dwarf shrub dominance (“restored”) and long-established, Calluna-dominated (“target”) upland heath. Soil respiration did not differ between the three vegetation types. Degraded areas contained a larger C pool in the vegetation but a lower soil C pool and total C stock than target areas. Restored areas held similar vegetation, soil and total C stocks to those of target areas. All areas had similar pools of recalcitrant C in their vegetation, but both target and restored areas contained more recalcitrant C in the soil, and in total, than degraded areas. The C benefit of restoration varied between sites, partly due to the abundance of Molinia caerulea in degraded vegetation at some sites, but the overall C benefit of restoring Calluna-dominated upland heath was 0.60 ± 0.70 t C ha−1 yr−1 since restoration. Restoration also increased the size of the recalcitrant C pool, which will increase C residence time and hence soil C accumulation in the longer term. Thus restoration of degraded areas is a valid option for promoting C sequestration within upland heath.
Victor M. Santana - One of the best experts on this subject based on the ideXlab platform.
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models for predicting fire ignition probability in Graminoids from boreo temperate moorland ecosystems
International Journal of Wildland Fire, 2016Co-Authors: Victor M. Santana, Rob H. MarrsAbstract:An increase in both the frequency and severity of wildfires in boreo–temperate ecosystems is predicted. Therefore, to develop efficient fire rating systems, the relationship between the fuel moisture content (FMC) of vegetation and ignition thresholds needs to be determined. We developed fire ignition probability models for three graminoid species collected in central England, but common in boreo–temperate ecosystems (Eriophorum angustifolium, E. vaginatum and Molinia caerulea). Specifically, we assessed through laboratory experiments (1) seasonal differences between early spring and late summer in fuel traits such as height, fuel load, fuel bulk density and dead fuel load proportion, and (2) the role of these fuel traits, environmental conditions and dead FMC in determining the probability of ignition. There were seasonal differences in fuel traits among species, with an increase in dead fuel load proportion after winter. The dead FMC was the only variable determining initial sustained ignitions. However, the seasonal differences in dead fuel were not sufficient to affect the FMC threshold at which Graminoids start to ignite. Graminoids begin to ignite at high levels of dead FMC, and there are differences between species (from 36.1% to 48.1%). This work assists in improving fire ignition predictions in graminoid-dominated ecosystems by providing warnings based on critical moisture thresholds.
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Models for predicting fire ignition probability in Graminoids from boreo–temperate moorland ecosystems
International Journal of Wildland Fire, 2016Co-Authors: Victor M. Santana, Rob H. MarrsAbstract:An increase in both the frequency and severity of wildfires in boreo–temperate ecosystems is predicted. Therefore, to develop efficient fire rating systems, the relationship between the fuel moisture content (FMC) of vegetation and ignition thresholds needs to be determined. We developed fire ignition probability models for three graminoid species collected in central England, but common in boreo–temperate ecosystems (Eriophorum angustifolium, E. vaginatum and Molinia caerulea). Specifically, we assessed through laboratory experiments (1) seasonal differences between early spring and late summer in fuel traits such as height, fuel load, fuel bulk density and dead fuel load proportion, and (2) the role of these fuel traits, environmental conditions and dead FMC in determining the probability of ignition. There were seasonal differences in fuel traits among species, with an increase in dead fuel load proportion after winter. The dead FMC was the only variable determining initial sustained ignitions. However, the seasonal differences in dead fuel were not sufficient to affect the FMC threshold at which Graminoids start to ignite. Graminoids begin to ignite at high levels of dead FMC, and there are differences between species (from 36.1% to 48.1%). This work assists in improving fire ignition predictions in graminoid-dominated ecosystems by providing warnings based on critical moisture thresholds.
Rob H. Marrs - One of the best experts on this subject based on the ideXlab platform.
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models for predicting fire ignition probability in Graminoids from boreo temperate moorland ecosystems
International Journal of Wildland Fire, 2016Co-Authors: Victor M. Santana, Rob H. MarrsAbstract:An increase in both the frequency and severity of wildfires in boreo–temperate ecosystems is predicted. Therefore, to develop efficient fire rating systems, the relationship between the fuel moisture content (FMC) of vegetation and ignition thresholds needs to be determined. We developed fire ignition probability models for three graminoid species collected in central England, but common in boreo–temperate ecosystems (Eriophorum angustifolium, E. vaginatum and Molinia caerulea). Specifically, we assessed through laboratory experiments (1) seasonal differences between early spring and late summer in fuel traits such as height, fuel load, fuel bulk density and dead fuel load proportion, and (2) the role of these fuel traits, environmental conditions and dead FMC in determining the probability of ignition. There were seasonal differences in fuel traits among species, with an increase in dead fuel load proportion after winter. The dead FMC was the only variable determining initial sustained ignitions. However, the seasonal differences in dead fuel were not sufficient to affect the FMC threshold at which Graminoids start to ignite. Graminoids begin to ignite at high levels of dead FMC, and there are differences between species (from 36.1% to 48.1%). This work assists in improving fire ignition predictions in graminoid-dominated ecosystems by providing warnings based on critical moisture thresholds.
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Models for predicting fire ignition probability in Graminoids from boreo–temperate moorland ecosystems
International Journal of Wildland Fire, 2016Co-Authors: Victor M. Santana, Rob H. MarrsAbstract:An increase in both the frequency and severity of wildfires in boreo–temperate ecosystems is predicted. Therefore, to develop efficient fire rating systems, the relationship between the fuel moisture content (FMC) of vegetation and ignition thresholds needs to be determined. We developed fire ignition probability models for three graminoid species collected in central England, but common in boreo–temperate ecosystems (Eriophorum angustifolium, E. vaginatum and Molinia caerulea). Specifically, we assessed through laboratory experiments (1) seasonal differences between early spring and late summer in fuel traits such as height, fuel load, fuel bulk density and dead fuel load proportion, and (2) the role of these fuel traits, environmental conditions and dead FMC in determining the probability of ignition. There were seasonal differences in fuel traits among species, with an increase in dead fuel load proportion after winter. The dead FMC was the only variable determining initial sustained ignitions. However, the seasonal differences in dead fuel were not sufficient to affect the FMC threshold at which Graminoids start to ignite. Graminoids begin to ignite at high levels of dead FMC, and there are differences between species (from 36.1% to 48.1%). This work assists in improving fire ignition predictions in graminoid-dominated ecosystems by providing warnings based on critical moisture thresholds.
Johanna E Freeman - One of the best experts on this subject based on the ideXlab platform.
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plant functional group composition on restored longleaf pine wiregrass pinus palustris aristida stricta savannas with a history of intensive agriculture
Natural Areas Journal, 2017Co-Authors: Johanna E Freeman, Kent Williges, Amber G Gardner, Erin H LeoneAbstract:ABSTRACT: We monitored plant community assembly during the first five years of longleaf pine—wiregrass (Pinus palustris—Aristida stricta) savanna restoration on four former bahiagrass (Paspalum notatum) pastures in peninsular Florida, which were restored via removal of exotic vegetation followed by mechanical planting with a wild-harvested native seed mix. We sampled randomly selected vegetation quadrats in each restored pasture annually, as well as randomly selected quadrats in each of four reference sites. All species were assigned to one of five functional groups (C4 Graminoids, C3 Graminoids, forbs, legumes, or shrubs) and one of three floristic quality categories (characteristic, pioneer, or weedy). Five years after restoration, we found that native C4 Graminoids had supplanted the sod-forming P. notatum as the dominant Graminoids on all sites. Restored sites had higher average C4 graminoid and forb cover than reference sites, but lower average species richness in both categories. Reference sites had...
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Plant Functional Group Composition on Restored Longleaf Pine—Wiregrass (Pinus palustris—Aristida stricta) Savannas with a History of Intensive Agriculture
Natural Areas Journal, 2017Co-Authors: Johanna E Freeman, Kent Williges, Amber G Gardner, Erin H LeoneAbstract:ABSTRACT: We monitored plant community assembly during the first five years of longleaf pine—wiregrass (Pinus palustris—Aristida stricta) savanna restoration on four former bahiagrass (Paspalum notatum) pastures in peninsular Florida, which were restored via removal of exotic vegetation followed by mechanical planting with a wild-harvested native seed mix. We sampled randomly selected vegetation quadrats in each restored pasture annually, as well as randomly selected quadrats in each of four reference sites. All species were assigned to one of five functional groups (C4 Graminoids, C3 Graminoids, forbs, legumes, or shrubs) and one of three floristic quality categories (characteristic, pioneer, or weedy). Five years after restoration, we found that native C4 Graminoids had supplanted the sod-forming P. notatum as the dominant Graminoids on all sites. Restored sites had higher average C4 graminoid and forb cover than reference sites, but lower average species richness in both categories. Reference sites had...
