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Hannu Fritze - One of the best experts on this subject based on the ideXlab platform.
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Impact of forest machinery on soil physical properties and microbiology of forestry-drained peatlands
2016Co-Authors: Dmitrii Lepilin, Bryn Kimura, Jori Uusitalo, Raija Laiho, Hannu Fritze, Ari Laurén, Eeva-stiina TuittilaAbstract:Treatment 2 Treatment 1 (Control) Introduction Forestry-drained peatlands occupy approximately 5.7 million ha and represent almost one fourth of the total forest surface in Finland. They are subjected to the same silvicultural harvesting operations as Upland Forests. However, although the potential of timber harvesting to cause detrimental effects on soil is well documented in Upland Forests, the knowledge on environmental impact of harvesting machinery on peat soils is still lacking.
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Cadmium in Upland Forests after vitality fertilization with wood ash—a summary of soil microbiological studies into the potential risk of cadmium release
Biology and Fertility of Soils, 2005Co-Authors: Jonna Perkiömäki, Hannu FritzeAbstract:The use of wood ash in forestry has been questioned because of the potential risk associated with its cadmium (Cd) content (1–30 mg kg^−1). In agriculture, wood ash is only allowed for use as a fertilizer when its Cd content is below 3 mg kg^−1. This restriction has not been applied to forest soils and there is a lack of knowledge about the potentially harmful effects of the Cd in wood ash on forest ecosystems. This paper summarizes our recent studies on the microbial communities of boreal coniferous forest humus exposed to Cd-containing wood ash treatment. The main objectives of our studies were to test if the Cd in wood ash has the potential to affect the humus layer microflora of coniferous Upland Forests and if it has the potential to enter the human food chain. These objectives were tested both in laboratory and field experiments with ash and ash spiked with Cd (in laboratory 400 or 1,000 mg Cd kg^−1 as CdO or CdCl_2; in field 400 mg Cd kg^−1 as CdO). In one study the dissolution of ash was accelerated by irrigating it with simulated acid rain (SAR). Wood ash increased humus layer pH and microbial activities (respiration or thymidine incorporation rates) and changed its microfloral community structure (Biolog, PLFA, 16S or 18S rDNA PCR-DGGE) in both laboratory and field experiments. Spiking ash with Cd induced no further changes in the above-mentioned variables compared to ash alone. The Cd added with wood ash did not become bioavailable as detected with a bacterial biosensor Bacillus subtilis BR151(pTOO24). The form and level of Cd added in the ash had no further effect on the microbiological variables studied. Irrigation of ash with SAR did not increase the amount of bioavailable Cd, although the dissolution rate of the ash was increased. The concentration of Cd in soil water and in the berries of Vaccinium uliginosum and V. vitis-idaea , and the amount of humus bioavailable Cd did not increase with applied ash or ash spiked with Cd although the ash spiked with Cd increased the amount of humus total and extractable Cd in the 4-year field study. Only the ash spiked with Cd and not the unspiked “normal” wood ash resulted in significantly higher Cd concentrations in the mushroom Lactarius rufus and a slight increase in the berries of Empetrum nigrum (first year only). In conclusion, the Cd in wood ash did not become bioavailable and harmful to forest soil microbes, or leach into the humus layer even when treated with simulated acid rain. It is thus safe to use wood ash as a fertilizer in Forests. However, since wood ash adds Cd to the environment, it is recommended that the same sites should not be fertilized with wood ash more than once. The effects of wood ash (3 t ha^−1) on forest soil humus layer microbes are long-term, lasting at least 20 years, and probably longer if higher application dose and/or hardened ash is used.
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cadmium in Upland Forests after vitality fertilization with wood ash a summary of soil microbiological studies into the potential risk of cadmium release
Biology and Fertility of Soils, 2005Co-Authors: Jonna Perkiömäki, Hannu FritzeAbstract:The use of wood ash in forestry has been questioned because of the potential risk associated with its cadmium (Cd) content (1–30 mg kg−1). In agriculture, wood ash is only allowed for use as a fertilizer when its Cd content is below 3 mg kg−1. This restriction has not been applied to forest soils and there is a lack of knowledge about the potentially harmful effects of the Cd in wood ash on forest ecosystems. This paper summarizes our recent studies on the microbial communities of boreal coniferous forest humus exposed to Cd-containing wood ash treatment. The main objectives of our studies were to test if the Cd in wood ash has the potential to affect the humus layer microflora of coniferous Upland Forests and if it has the potential to enter the human food chain. These objectives were tested both in laboratory and field experiments with ash and ash spiked with Cd (in laboratory 400 or 1,000 mg Cd kg−1 as CdO or CdCl2; in field 400 mg Cd kg−1 as CdO). In one study the dissolution of ash was accelerated by irrigating it with simulated acid rain (SAR). Wood ash increased humus layer pH and microbial activities (respiration or thymidine incorporation rates) and changed its microfloral community structure (Biolog, PLFA, 16S or 18S rDNA PCR-DGGE) in both laboratory and field experiments. Spiking ash with Cd induced no further changes in the above-mentioned variables compared to ash alone. The Cd added with wood ash did not become bioavailable as detected with a bacterial biosensor Bacillus subtilis BR151(pTOO24). The form and level of Cd added in the ash had no further effect on the microbiological variables studied. Irrigation of ash with SAR did not increase the amount of bioavailable Cd, although the dissolution rate of the ash was increased. The concentration of Cd in soil water and in the berries of Vaccinium uliginosum and V. vitis-idaea, and the amount of humus bioavailable Cd did not increase with applied ash or ash spiked with Cd although the ash spiked with Cd increased the amount of humus total and extractable Cd in the 4-year field study. Only the ash spiked with Cd and not the unspiked “normal” wood ash resulted in significantly higher Cd concentrations in the mushroom Lactarius rufus and a slight increase in the berries of Empetrum nigrum (first year only). In conclusion, the Cd in wood ash did not become bioavailable and harmful to forest soil microbes, or leach into the humus layer even when treated with simulated acid rain. It is thus safe to use wood ash as a fertilizer in Forests. However, since wood ash adds Cd to the environment, it is recommended that the same sites should not be fertilized with wood ash more than once. The effects of wood ash (3 t ha−1) on forest soil humus layer microbes are long-term, lasting at least 20 years, and probably longer if higher application dose and/or hardened ash is used.
Jonna Perkiömäki - One of the best experts on this subject based on the ideXlab platform.
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Cadmium in Upland Forests after vitality fertilization with wood ash—a summary of soil microbiological studies into the potential risk of cadmium release
Biology and Fertility of Soils, 2005Co-Authors: Jonna Perkiömäki, Hannu FritzeAbstract:The use of wood ash in forestry has been questioned because of the potential risk associated with its cadmium (Cd) content (1–30 mg kg^−1). In agriculture, wood ash is only allowed for use as a fertilizer when its Cd content is below 3 mg kg^−1. This restriction has not been applied to forest soils and there is a lack of knowledge about the potentially harmful effects of the Cd in wood ash on forest ecosystems. This paper summarizes our recent studies on the microbial communities of boreal coniferous forest humus exposed to Cd-containing wood ash treatment. The main objectives of our studies were to test if the Cd in wood ash has the potential to affect the humus layer microflora of coniferous Upland Forests and if it has the potential to enter the human food chain. These objectives were tested both in laboratory and field experiments with ash and ash spiked with Cd (in laboratory 400 or 1,000 mg Cd kg^−1 as CdO or CdCl_2; in field 400 mg Cd kg^−1 as CdO). In one study the dissolution of ash was accelerated by irrigating it with simulated acid rain (SAR). Wood ash increased humus layer pH and microbial activities (respiration or thymidine incorporation rates) and changed its microfloral community structure (Biolog, PLFA, 16S or 18S rDNA PCR-DGGE) in both laboratory and field experiments. Spiking ash with Cd induced no further changes in the above-mentioned variables compared to ash alone. The Cd added with wood ash did not become bioavailable as detected with a bacterial biosensor Bacillus subtilis BR151(pTOO24). The form and level of Cd added in the ash had no further effect on the microbiological variables studied. Irrigation of ash with SAR did not increase the amount of bioavailable Cd, although the dissolution rate of the ash was increased. The concentration of Cd in soil water and in the berries of Vaccinium uliginosum and V. vitis-idaea , and the amount of humus bioavailable Cd did not increase with applied ash or ash spiked with Cd although the ash spiked with Cd increased the amount of humus total and extractable Cd in the 4-year field study. Only the ash spiked with Cd and not the unspiked “normal” wood ash resulted in significantly higher Cd concentrations in the mushroom Lactarius rufus and a slight increase in the berries of Empetrum nigrum (first year only). In conclusion, the Cd in wood ash did not become bioavailable and harmful to forest soil microbes, or leach into the humus layer even when treated with simulated acid rain. It is thus safe to use wood ash as a fertilizer in Forests. However, since wood ash adds Cd to the environment, it is recommended that the same sites should not be fertilized with wood ash more than once. The effects of wood ash (3 t ha^−1) on forest soil humus layer microbes are long-term, lasting at least 20 years, and probably longer if higher application dose and/or hardened ash is used.
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cadmium in Upland Forests after vitality fertilization with wood ash a summary of soil microbiological studies into the potential risk of cadmium release
Biology and Fertility of Soils, 2005Co-Authors: Jonna Perkiömäki, Hannu FritzeAbstract:The use of wood ash in forestry has been questioned because of the potential risk associated with its cadmium (Cd) content (1–30 mg kg−1). In agriculture, wood ash is only allowed for use as a fertilizer when its Cd content is below 3 mg kg−1. This restriction has not been applied to forest soils and there is a lack of knowledge about the potentially harmful effects of the Cd in wood ash on forest ecosystems. This paper summarizes our recent studies on the microbial communities of boreal coniferous forest humus exposed to Cd-containing wood ash treatment. The main objectives of our studies were to test if the Cd in wood ash has the potential to affect the humus layer microflora of coniferous Upland Forests and if it has the potential to enter the human food chain. These objectives were tested both in laboratory and field experiments with ash and ash spiked with Cd (in laboratory 400 or 1,000 mg Cd kg−1 as CdO or CdCl2; in field 400 mg Cd kg−1 as CdO). In one study the dissolution of ash was accelerated by irrigating it with simulated acid rain (SAR). Wood ash increased humus layer pH and microbial activities (respiration or thymidine incorporation rates) and changed its microfloral community structure (Biolog, PLFA, 16S or 18S rDNA PCR-DGGE) in both laboratory and field experiments. Spiking ash with Cd induced no further changes in the above-mentioned variables compared to ash alone. The Cd added with wood ash did not become bioavailable as detected with a bacterial biosensor Bacillus subtilis BR151(pTOO24). The form and level of Cd added in the ash had no further effect on the microbiological variables studied. Irrigation of ash with SAR did not increase the amount of bioavailable Cd, although the dissolution rate of the ash was increased. The concentration of Cd in soil water and in the berries of Vaccinium uliginosum and V. vitis-idaea, and the amount of humus bioavailable Cd did not increase with applied ash or ash spiked with Cd although the ash spiked with Cd increased the amount of humus total and extractable Cd in the 4-year field study. Only the ash spiked with Cd and not the unspiked “normal” wood ash resulted in significantly higher Cd concentrations in the mushroom Lactarius rufus and a slight increase in the berries of Empetrum nigrum (first year only). In conclusion, the Cd in wood ash did not become bioavailable and harmful to forest soil microbes, or leach into the humus layer even when treated with simulated acid rain. It is thus safe to use wood ash as a fertilizer in Forests. However, since wood ash adds Cd to the environment, it is recommended that the same sites should not be fertilized with wood ash more than once. The effects of wood ash (3 t ha−1) on forest soil humus layer microbes are long-term, lasting at least 20 years, and probably longer if higher application dose and/or hardened ash is used.
Roger W. Ruess - One of the best experts on this subject based on the ideXlab platform.
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Seasonal Patterns of Climate Controls Over Nitrogen Fixation by Alnus viridis subsp. Fruticosa in a Secondary Successional Chronosequence in Interior Alaska
Ecoscience, 2009Co-Authors: Jennifer S. Mitchell, Roger W. RuessAbstract:Abstract: Patterns of and controls over N2 fixation by green alder were studied in post-fire, mid-succession, and white spruce Upland Forests in interior Alaska, focusing on the hypothesis that ecosystem-level nitrogen (N) inputs decrease with successional development. N2-fixation rates tracked plant phenology during the 1997 (drought) and 1998 (normal precipitation) growing seasons. The best model for predicting acetylene reductase activity (ARA, µmol C2H4·g noduleDWT-1·h-1) across all stands and sampling periods included a linear response to soil temperature and a quadratic response to Julian day (r2 = 0.23, P < 0.0001). There were few significant relationships between seasonal maximum values for ARA and measured leaf traits; however, we did detect an inverse correlation between foliar N to P ratio and seasonal maximum ARA. During 1998, stands with higher maximum ARA had higher soil %N, and maximum ARA was positively correlated with subcanopy %P in O and A soil horizons. During 1997, leaf %P and N resor...
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N_2 fixing alder (Alnus viridis spp. fruticosa) effects on soil properties across a secondary successional chronosequence in interior Alaska
Biogeochemistry, 2009Co-Authors: Jennifer S. Mitchell, Roger W. RuessAbstract:Green alder ( Alnus viridis ssp. fruticosa ) is a dominant understory shrub during secondary successional development of Upland Forests throughout interior Alaska, where it contributes substantially to the nitrogen (N) economy through atmospheric N_2 fixation. Across a replicated 200+ year old vegetation chronosequence, we tested the hypotheses that green alder has strong effects on soil chemical properties, and that ecosystem-level N inputs via N_2 fixation decrease with secondary successional stand development. Across early-, mid-, and late-successional stands, alder created islands of elevated soil N and carbon (C), depleted soil phosphorus (P), and more acidic soils. These effects translated to the stand-level in response to alder stem density. Although neither N_2 fixation nor nodule biomass differed among stand types, increases in alder densities with successional time translated to increasing N inputs. Estimates of annual N inputs by A. viridis averaged across the Upland chronosequence (6.6 ± 1.2 kg N ha^−1 year^−1) are substantially less than inputs during early succession by Alnus tenuifolia growing along Alaskan floodplains. However, late-succession Upland Forests, where densities of A. viridis are highest, may persist for centuries, depending on fire return interval. This pattern of prolonged N inputs to late successional Forests contradicts established theory predicting declines in N_2-fixation rates and N_2-fixer abundance as stands age.
Diana L. Olson - One of the best experts on this subject based on the ideXlab platform.
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riparian and adjacent Upland Forests burned synchronously during dry years in eastern oregon 1650 1900 ce usa
International Journal of Wildland Fire, 2020Co-Authors: Grant L. Harley, Emily K. Heyerdahl, James D. Johnston, Diana L. OlsonAbstract:Riparian Forests link terrestrial and freshwater communities and therefore understanding the landscape context of fire regimes in these Forests is critical to fully understanding the landscape ecology. However, few direct studies of fire regimes exist for riparian Forests, especially in the landscape context of adjacent Upland Forests or studies of long-term climate drivers of riparian forest fires. We reconstructed a low-severity fire history from tree rings in 38 1-ha riparian plots and combined them with existing fire histories from 104 adjacent Upland plots to yield 2633 fire scars sampled on 454 trees. Historically (1650–1900), low-severity fires burned more frequently in Upland than in riparian plots, but this difference was not significant (P = 0.15). During more than half of the fire years at both sites, fires were extensive and burned synchronously in riparian and Upland plots, and climate was significantly dry during these years. However, climate was not significantly dry when fires burned in only one plot type. Historically, entire riparian zones likely burned in these two study sites of the Blue Mountains during dry years. This study suggests that riparian and Upland Forests could be managed similarly, especially given the projected increases to fire frequency and intensity from impending climate change.
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Riparian and adjacent Upland Forests burned synchronously during dry years in eastern Oregon (1650–1900 CE), USA
International Journal of Wildland Fire, 2020Co-Authors: Grant L. Harley, Emily K. Heyerdahl, James D. Johnston, Diana L. OlsonAbstract:Riparian Forests link terrestrial and freshwater communities and therefore understanding the landscape context of fire regimes in these Forests is critical to fully understanding the landscape ecology. However, few direct studies of fire regimes exist for riparian Forests, especially in the landscape context of adjacent Upland Forests or studies of long-term climate drivers of riparian forest fires. We reconstructed a low-severity fire history from tree rings in 38 1-ha riparian plots and combined them with existing fire histories from 104 adjacent Upland plots to yield 2633 fire scars sampled on 454 trees. Historically (1650–1900), low-severity fires burned more frequently in Upland than in riparian plots, but this difference was not significant (P = 0.15). During more than half of the fire years at both sites, fires were extensive and burned synchronously in riparian and Upland plots, and climate was significantly dry during these years. However, climate was not significantly dry when fires burned in only one plot type. Historically, entire riparian zones likely burned in these two study sites of the Blue Mountains during dry years. This study suggests that riparian and Upland Forests could be managed similarly, especially given the projected increases to fire frequency and intensity from impending climate change.
Jennifer S. Mitchell - One of the best experts on this subject based on the ideXlab platform.
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Seasonal Patterns of Climate Controls Over Nitrogen Fixation by Alnus viridis subsp. Fruticosa in a Secondary Successional Chronosequence in Interior Alaska
Ecoscience, 2009Co-Authors: Jennifer S. Mitchell, Roger W. RuessAbstract:Abstract: Patterns of and controls over N2 fixation by green alder were studied in post-fire, mid-succession, and white spruce Upland Forests in interior Alaska, focusing on the hypothesis that ecosystem-level nitrogen (N) inputs decrease with successional development. N2-fixation rates tracked plant phenology during the 1997 (drought) and 1998 (normal precipitation) growing seasons. The best model for predicting acetylene reductase activity (ARA, µmol C2H4·g noduleDWT-1·h-1) across all stands and sampling periods included a linear response to soil temperature and a quadratic response to Julian day (r2 = 0.23, P < 0.0001). There were few significant relationships between seasonal maximum values for ARA and measured leaf traits; however, we did detect an inverse correlation between foliar N to P ratio and seasonal maximum ARA. During 1998, stands with higher maximum ARA had higher soil %N, and maximum ARA was positively correlated with subcanopy %P in O and A soil horizons. During 1997, leaf %P and N resor...
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N_2 fixing alder (Alnus viridis spp. fruticosa) effects on soil properties across a secondary successional chronosequence in interior Alaska
Biogeochemistry, 2009Co-Authors: Jennifer S. Mitchell, Roger W. RuessAbstract:Green alder ( Alnus viridis ssp. fruticosa ) is a dominant understory shrub during secondary successional development of Upland Forests throughout interior Alaska, where it contributes substantially to the nitrogen (N) economy through atmospheric N_2 fixation. Across a replicated 200+ year old vegetation chronosequence, we tested the hypotheses that green alder has strong effects on soil chemical properties, and that ecosystem-level N inputs via N_2 fixation decrease with secondary successional stand development. Across early-, mid-, and late-successional stands, alder created islands of elevated soil N and carbon (C), depleted soil phosphorus (P), and more acidic soils. These effects translated to the stand-level in response to alder stem density. Although neither N_2 fixation nor nodule biomass differed among stand types, increases in alder densities with successional time translated to increasing N inputs. Estimates of annual N inputs by A. viridis averaged across the Upland chronosequence (6.6 ± 1.2 kg N ha^−1 year^−1) are substantially less than inputs during early succession by Alnus tenuifolia growing along Alaskan floodplains. However, late-succession Upland Forests, where densities of A. viridis are highest, may persist for centuries, depending on fire return interval. This pattern of prolonged N inputs to late successional Forests contradicts established theory predicting declines in N_2-fixation rates and N_2-fixer abundance as stands age.
