The Experts below are selected from a list of 306 Experts worldwide ranked by ideXlab platform
Roderick J. Fensham - One of the best experts on this subject based on the ideXlab platform.
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Fire after a mast year triggers mass recruitment of slender mulga (Acacia aptaneura), a desert shrub with heat‐stimulated germination
American Journal of Botany, 2017Co-Authors: Boyd R. Wright, Roderick J. FenshamAbstract:PREMISE OF THE STUDY: Fire typically triggers extensive regeneration of plants with heat-stimulated germination by causing short periods of intense Soil Heating. If plants with heat-stimulated germination are also subject to seed predation and display mast-seeding cycles, postfire recruitment may be contingent on the seedfall density of prefire masts, and on whether granivores are satiated at the time of fire.
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Fire after a mast year triggers mass recruitment of slender mulga (Acacia aptaneura), a desert shrub with heat‐stimulated germination
American Journal of Botany, 2017Co-Authors: Boyd R. Wright, Roderick J. FenshamAbstract:PREMISE OF THE STUDY: Fire typically triggers extensive regeneration of plants with heat-stimulated germination by causing short periods of intense Soil Heating. If plants with heat-stimulated germination are also subject to seed predation and display mast-seeding cycles, postfire recruitment may be contingent on the seedfall density of prefire masts, and on whether granivores are satiated at the time of fire.
Boyd R. Wright - One of the best experts on this subject based on the ideXlab platform.
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Fire after a mast year triggers mass recruitment of slender mulga (Acacia aptaneura), a desert shrub with heat‐stimulated germination
American Journal of Botany, 2017Co-Authors: Boyd R. Wright, Roderick J. FenshamAbstract:PREMISE OF THE STUDY: Fire typically triggers extensive regeneration of plants with heat-stimulated germination by causing short periods of intense Soil Heating. If plants with heat-stimulated germination are also subject to seed predation and display mast-seeding cycles, postfire recruitment may be contingent on the seedfall density of prefire masts, and on whether granivores are satiated at the time of fire.
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Fire after a mast year triggers mass recruitment of slender mulga (Acacia aptaneura), a desert shrub with heat‐stimulated germination
American Journal of Botany, 2017Co-Authors: Boyd R. Wright, Roderick J. FenshamAbstract:PREMISE OF THE STUDY: Fire typically triggers extensive regeneration of plants with heat-stimulated germination by causing short periods of intense Soil Heating. If plants with heat-stimulated germination are also subject to seed predation and display mast-seeding cycles, postfire recruitment may be contingent on the seedfall density of prefire masts, and on whether granivores are satiated at the time of fire.
A. Lükewille - One of the best experts on this subject based on the ideXlab platform.
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The CLIMEX Soil-Heating experiment: Soil response after 2 years of treatment
Biology and Fertility of Soils, 1999Co-Authors: P. S. J. Verburg, W. K. P. Van Loon, A. LükewilleAbstract:Most model predictions concerning the response of boreal forest ecosystems to climate change are inferred from small-scale experiments on artificial, simplified systems. Whole-ecosystem experiments designed to validate these models are scarce. We experimentally manipulated a small forested catchment in southern Norway by increasing Soil temperature (+3 °C in summer to +5 °C in winter) using Heating cables installed at 1 cm depth in the litter layer. Especially nitrification in the 0 to 10-cm Soil layer increased as a result of the climate manipulation. Betula litter, produced after exposing trees for 2 years to ambient and elevated CO2 in greenhouses, was incubated for 1 year in the manipulated catchment. Exposure to elevated CO2 did not affect the C/N ratio or decomposition of the Betula litter, but lignin content decreased by 10%. We found no effect of elevated temperature on litter decomposition, probably due to desiccation of the litter. The Heating cables caused a permanent increase in Soil temperature in this Soil layer, but when Soils were dry, the temperature difference between control and heated plots decreased with increasing distance from the cables. When Soils were wet, no gradients in temperature increase occurred.
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The CLIMEX Soil-Heating experiment: Soil response after 2 years of treatment
Biology and Fertility of Soils, 1999Co-Authors: P. S. J. Verburg, W. K. P. Van Loon, A. LükewilleAbstract:Most model predictions concerning the response of boreal forest ecosystems to climate change are inferred from small-scale experiments on artificial, simplified systems. Whole-ecosystem experiments designed to validate these models are scarce. We experimentally manipulated a small forested catchment in southern Norway by increasing Soil temperature (+3 °C in summer to +5 °C in winter) using Heating cables installed at 1 cm depth in the litter layer. Especially nitrification in the 0 to 10-cm Soil layer increased as a result of the climate manipulation. Betula litter, produced after exposing trees for 2 years to ambient and elevated CO2 in greenhouses, was incubated for 1 year in the manipulated catchment. Exposure to elevated CO2 did not affect the C/N ratio or decomposition of the Betula litter, but lignin content decreased by 10%. We found no effect of elevated temperature on litter decomposition, probably due to desiccation of the litter. The Heating cables caused a permanent increase in Soil temperature in this Soil layer, but when Soils were dry, the temperature difference between control and heated plots decreased with increasing distance from the cables. When Soils were wet, no gradients in temperature increase occurred.
Trofim C Maximov - One of the best experts on this subject based on the ideXlab platform.
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above and below ground responses of four tundra plant functional types to deep Soil Heating and surface Soil fertilization
Journal of Ecology, 2017Co-Authors: Peng Wang, Juul Limpens, Daan Blok, Trofim C Maximov, Frank Berendse, Liesje Mommer, Jasper Van Ruijven, Ake Nauta, Gabriela SchaepmanstrubAbstract:1.Climate warming is faster in the Arctic than the global average. Nutrient availability in the tundra Soil is expected to increase by climate warming through 1) accelerated nutrient mobilization in the surface Soil layers, and 2) increased thawing depths during the growing season which increases accessibility of nutrients in the deeper Soil layers. Both processes may initiate shifts in tundra vegetation composition. It is important to understand the effects of these two processes on tundra plant functional types. 2.We manipulated Soil thawing depth and nutrient availability at a Northeast-Siberian tundra site to investigate their effects on above and belowground responses of four plant functional types (grasses, sedges, deciduous shrubs and evergreen shrubs). Seasonal thawing was accelerated with Heating cables at ~15 cm depth without warming the surface Soil, whereas nutrient availability was increased in the surface Soil by adding slow-release NPK fertilizer at ~5 cm depth. A combination of these two treatments was also included. This is the first field experiment specifically investigating the effects of accelerated thawing in tundra ecosystems. 3.Deep Soil Heating increased the aboveground biomass of sedges, the deepest-rooted plant functional type in our study, but did not affect biomass of the other plant functional types. In contrast, fertilization increased aboveground biomass of the two dwarf shrub functional types, which both had very shallow root systems. Grasses showed the strongest response to fertilization, both above and belowground. Grasses were deep-rooted, and they showed the highest plasticity in terms of vertical root distribution, as grass root distribution shifted to deep and surface Soil in response to deep Soil Heating and surface Soil fertilization, respectively. 4.Synthesis - Our results indicate that increased thawing depth can only benefit deep-rooted sedges, while the shallow-rooted dwarf shrubs as well as flexible-rooted grasses take advantage of increased nutrient availability in the upper Soil layers. Our results suggest that grasses have the highest root plasticity, which enables them to be more competitive in rapidly changing environments. We conclude that root vertical distribution strategies are important for vegetation responses to climate-induced increases in Soil nutrient availability in Arctic tundra, and that future shifts in vegetation composition will depend on the balance between changes in thawing depth and nutrient availability in the surface Soil.
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Above‐ and below‐ground responses of four tundra plant functional types to deep Soil Heating and surface Soil fertilization
Journal of Ecology, 2017Co-Authors: Peng Wang, A.l. Nauta, Gabriela Schaepman-strub, Juul Limpens, Daan Blok, Trofim C Maximov, Frank Berendse, Jasper Ruijven, Liesje Mommer, Monique M. P. D. HeijmansAbstract:1.Climate warming is faster in the Arctic than the global average. Nutrient availability in the tundra Soil is expected to increase by climate warming through 1) accelerated nutrient mobilization in the surface Soil layers, and 2) increased thawing depths during the growing season which increases accessibility of nutrients in the deeper Soil layers. Both processes may initiate shifts in tundra vegetation composition. It is important to understand the effects of these two processes on tundra plant functional types. 2.We manipulated Soil thawing depth and nutrient availability at a Northeast-Siberian tundra site to investigate their effects on above and belowground responses of four plant functional types (grasses, sedges, deciduous shrubs and evergreen shrubs). Seasonal thawing was accelerated with Heating cables at ~15 cm depth without warming the surface Soil, whereas nutrient availability was increased in the surface Soil by adding slow-release NPK fertilizer at ~5 cm depth. A combination of these two treatments was also included. This is the first field experiment specifically investigating the effects of accelerated thawing in tundra ecosystems. 3.Deep Soil Heating increased the aboveground biomass of sedges, the deepest-rooted plant functional type in our study, but did not affect biomass of the other plant functional types. In contrast, fertilization increased aboveground biomass of the two dwarf shrub functional types, which both had very shallow root systems. Grasses showed the strongest response to fertilization, both above and belowground. Grasses were deep-rooted, and they showed the highest plasticity in terms of vertical root distribution, as grass root distribution shifted to deep and surface Soil in response to deep Soil Heating and surface Soil fertilization, respectively. 4.Synthesis - Our results indicate that increased thawing depth can only benefit deep-rooted sedges, while the shallow-rooted dwarf shrubs as well as flexible-rooted grasses take advantage of increased nutrient availability in the upper Soil layers. Our results suggest that grasses have the highest root plasticity, which enables them to be more competitive in rapidly changing environments. We conclude that root vertical distribution strategies are important for vegetation responses to climate-induced increases in Soil nutrient availability in Arctic tundra, and that future shifts in vegetation composition will depend on the balance between changes in thawing depth and nutrient availability in the surface Soil.
P. S. J. Verburg - One of the best experts on this subject based on the ideXlab platform.
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The CLIMEX Soil-Heating experiment: Soil response after 2 years of treatment
Biology and Fertility of Soils, 1999Co-Authors: P. S. J. Verburg, W. K. P. Van Loon, A. LükewilleAbstract:Most model predictions concerning the response of boreal forest ecosystems to climate change are inferred from small-scale experiments on artificial, simplified systems. Whole-ecosystem experiments designed to validate these models are scarce. We experimentally manipulated a small forested catchment in southern Norway by increasing Soil temperature (+3 °C in summer to +5 °C in winter) using Heating cables installed at 1 cm depth in the litter layer. Especially nitrification in the 0 to 10-cm Soil layer increased as a result of the climate manipulation. Betula litter, produced after exposing trees for 2 years to ambient and elevated CO2 in greenhouses, was incubated for 1 year in the manipulated catchment. Exposure to elevated CO2 did not affect the C/N ratio or decomposition of the Betula litter, but lignin content decreased by 10%. We found no effect of elevated temperature on litter decomposition, probably due to desiccation of the litter. The Heating cables caused a permanent increase in Soil temperature in this Soil layer, but when Soils were dry, the temperature difference between control and heated plots decreased with increasing distance from the cables. When Soils were wet, no gradients in temperature increase occurred.
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The CLIMEX Soil-Heating experiment: Soil response after 2 years of treatment
Biology and Fertility of Soils, 1999Co-Authors: P. S. J. Verburg, W. K. P. Van Loon, A. LükewilleAbstract:Most model predictions concerning the response of boreal forest ecosystems to climate change are inferred from small-scale experiments on artificial, simplified systems. Whole-ecosystem experiments designed to validate these models are scarce. We experimentally manipulated a small forested catchment in southern Norway by increasing Soil temperature (+3 °C in summer to +5 °C in winter) using Heating cables installed at 1 cm depth in the litter layer. Especially nitrification in the 0 to 10-cm Soil layer increased as a result of the climate manipulation. Betula litter, produced after exposing trees for 2 years to ambient and elevated CO2 in greenhouses, was incubated for 1 year in the manipulated catchment. Exposure to elevated CO2 did not affect the C/N ratio or decomposition of the Betula litter, but lignin content decreased by 10%. We found no effect of elevated temperature on litter decomposition, probably due to desiccation of the litter. The Heating cables caused a permanent increase in Soil temperature in this Soil layer, but when Soils were dry, the temperature difference between control and heated plots decreased with increasing distance from the cables. When Soils were wet, no gradients in temperature increase occurred.