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Sophie Zechmeisterboltenstern - One of the best experts on this subject based on the ideXlab platform.
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microbial functionality as affected by experimental warming of a temperate Mountain Forest soil a metaproteomics survey
Applied Soil Ecology, 2017Co-Authors: Andreas Schindlbacher, Stephan Fuchs, Dong Liu, Katharina M Keiblinger, Uwe Wegner, Hanyin Sun, Christian Lassek, Katharina Riedel, Sophie ZechmeisterboltensternAbstract:Abstract Soil microbes play an important role in terrestrial carbon (C) cycling, but their functional response to global warming remains yet unclear. Soil metaproteomics has the potential to contribute to a better understanding of warming effects on soil microbes as proteins specifically represent active microbes and their physiological functioning. To quantify warming effects on microbial proteins and their distribution among different functional and phylogenetic groups, we sampled Forest soil that had been artificially warmed (+4 °C) during seven consecutive growing seasons and analyzed its metaproteomic fingerprint and linked to soil respiration as a fundamental ecosystem service. Bacterial protein abundances largely exceeded fungal abundances at the study site but protein abundances showed only subtle differences among control and warmed soil at the phylum and class level, i.e. a temperature-induced decrease in Firmicutes , an increase in Agaricomycetes and Actinobacteria , and a decrease in the Asco/Basidiomycota ratio. Community function in warmed soil showed a clear trend towards increased proteins involved in microbial energy production and conversion, related to the increased CO 2 efflux from warmed soil as a result of stress environmental conditions. The differences in community function could be related to specific phyla using metaproteomics, indicating that microbial adaptation to long-term soil warming mainly changed microbial functions, which is related to enhanced soil respiration. The response of soil respiration to warming (+35% soil CO 2 efflux during sampling) has not changed over time. Accordingly, potential long-term microbial adaptations to soil warming were too subtle to affect soil respiration rates or, were overlaid by other co-varying factors (e.g. substrate availability).
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experimental warming effects on the microbial community of a temperate Mountain Forest soil
Soil Biology & Biochemistry, 2011Co-Authors: Andreas Schindlbacher, A S Rodler, Melanie Kuffner, Barbara Kitzler, Angela Sessitsch, Sophie ZechmeisterboltensternAbstract:Soil microbial communities mediate the decomposition of soil organic matter (SOM). The amount of carbon (C) that is respired leaves the soil as CO2 (soil respiration) and causes one of the greatest fluxes in the global carbon cycle. How soil microbial communities will respond to global warming, however, is not well understood. To elucidate the effect of warming on the microbial community we analyzed soil from the soil warming experiment Achenkirch, Austria. Soil of a mature spruce Forest was warmed by 4 °C during snow-free seasons since 2004. Repeated soil sampling from control and warmed plots took place from 2008 until 2010. We monitored microbial biomass C and nitrogen (N). Microbial community composition was assessed by phospholipid fatty acid analysis (PLFA) and by quantitative real time polymerase chain reaction (qPCR) of ribosomal RNA genes. Microbial metabolic activity was estimated by soil respiration to biomass ratios and RNA to DNA ratios. Soil warming did not affect microbial biomass, nor did warming affect the abundances of most microbial groups. Warming significantly enhanced microbial metabolic activity in terms of soil respiration per amount of microbial biomass C. Microbial stress biomarkers were elevated in warmed plots. In summary, the 4 °C increase in soil temperature during the snow-free season had no influence on microbial community composition and biomass but strongly increased microbial metabolic activity and hence reduced carbon use efficiency.
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root trenching a useful tool to estimate autotrophic soil respiration a case study in an austrian Mountain Forest
European Journal of Forest Research, 2010Co-Authors: Eugenio Diazpines, Andreas Schindlbacher, Michael Pfeffer, Robert Jandl, Sophie Zechmeisterboltenstern, Agustin RubioAbstract:We conducted a trenching experiment in a Mountain Forest in order to assess the contribution of the autotrophic respiration to total soil respiration and evaluate trenching as a technique to achieve it. We hypothesised that the trenching experiment would alter both microbial bio- mass and microbial community structure and that Wne roots (less than 2 mm diameter) would be decomposed within one growing season. Soil CO 2 eZux was measured roughly biweekly over two growing seasons. Root presence and morphology parameters, as well as the soil microbial com- munity were measured prior to trenching, 5 and 15 months after trenching. The trenched plots emitted about 20 and 30% less CO2 than the control plots in the Wrst and second growing season, respectively. Roots died in trenched plots, but root decay was slow. After 5 and 15 months, Wne root biomass was decreased by 9% (not statistically diVerent) and 30%, (statistically diVerent) respectively. When we corrected for the additional trenched-plot CO 2 eZux due to Wne root decomposition, the autotrophic soil respiration rose to »26% of the total soil respiration for the Wrst grow- ing season, and to »44% for the second growing season. Soil microbial biomass and community structure was not altered by the end of the second growing season. We con- clude that trenching can give accurate estimates of the auto- trophic and heterotrophic components of soil respiration, if methodological side eVects are accounted for, only.
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nitrogen dynamics of a Mountain Forest on dolomitic limestone a scenario based risk assessment
Environmental Pollution, 2008Co-Authors: Robert Jandl, Friedl Herman, Stefan Smidt, Klaus Butterbachbahl, Michael Englisch, Klaus Katzensteiner, Manfred J Lexer, Friederike Strebl, Sophie ZechmeisterboltensternAbstract:Abstract The dominant nitrogen (N) fluxes were simulated in a Mountain Forest ecosystem on dolomitic bedrock in the Austrian Alps. Based on an existing small-scale climate model the simulation encompassed the present situation and a 50-yr projection. The investigated scenarios were current climate, current N deposition (SC1) and future climate (+2.5 °C and +10% annual precipitation) with three levels of N deposition (SC2, 3, 4). The microbially mediated N transformation, including the emission of nitrogen oxides, was calculated with PnET-N-DNDC. Soil hydrology was calculated with HYDRUS and was used to estimate the leaching of nitrate. The expected change of the Forest ecosystem due to changes of the climate and the N availability was simulated with PICUS. The incentive for the project was the fact that Forests on dolomitic limestone stock on shallow Rendzic Leptosols that are rich in soil organic matter are considered highly sensitive to the expected environmental changes. The simulation results showed a strong effect due to increased temperatures and to elevated levels of N deposition. The outflux of N, both as nitrate (6–25 kg N ha−1 yr−1) and nitrogen oxides (1–2 kg N ha−1 yr−1), from the Forest ecosystem are expected to increase. Temperature exerts a stronger effect on the N2O emission than the increased rate of N deposition. The main part of the N emission will occur as N2 (15 kg N ha−1 yr−1). The total N loss is partially offset by increased rates of N uptake in the biomass due to an increase in Forest productivity.
Marieke Sassen - One of the best experts on this subject based on the ideXlab platform.
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fuelwood collection and its impacts on a protected tropical Mountain Forest in uganda
Forest Ecology and Management, 2015Co-Authors: Marieke Sassen, Douglas Sheil, Kenneth E. GillerAbstract:Local communities who live close to protected tropical Forests often depend on them for woodfuel, their main source of energy. The impacts of fuelwood extraction in humid Forests are rarely studied, yet the extraction of wood for fuel can impact Forest structure, function and biodiversity. We assessed the effects of fuelwood collection on the Forest of Mt Elgon National Park (Uganda). We interviewed 192 households about fuelwood use and surveyed dead wood in 81 plots inside the park. Forest was the most important source of fuelwood. People collected on average between 1.1 and 2.0m3 of fuelwood per capita per year. Other activities involving wood fuel extraction from the Forest included illegal commercial fuelwood harvesting and charcoal making. Quantities of dead wood were affected by fuelwood collection up to at least 1000m inside the boundary of the park. Depletion of dead wood inside the park was greater in the sites where the population was most dense. Nevertheless, people who planted more trees on their own land perceived land outside the park to be important and valued old growth Forest less as a source of fuelwood. Highly-preferred tree species were most depleted, particularly when they were also valued timber trees, such as Prunus africana, Popocarpus milianjianus, Allophylus abyssinicus and Olea spp. Locally dominant species were less affected. Impacts varied among sites depending on the history of agricultural encroachment and locally-specific Forest uses, e.g. harvesting of trees for poles or use of the Forest land for grazing. Allowing the collection of dead wood in Forests is double-edged as it creates opportunities for other activities that are more damaging. Demand for wood fuel from tropical Forests is still likely to grow in the foreseeable future. Our results indicate that the Forest may become more degraded as a result, with negative consequences for the people who depend on the Forest and for conservation. Research into local ecological and cultural contexts and perceptions concerning costs and benefits can help devise more sustainable management options, including alternative sources of fuel.
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fuelwood collection and its impacts on a protected tropical Mountain Forest in uganda
Forest Ecology and Management, 2015Co-Authors: Marieke Sassen, Douglas Sheil, Kenneth E. GillerAbstract:Local communities who live close to protected tropical Forests often depend on them for woodfuel, their main source of energy. The impacts of fuelwood extraction in humid Forests are rarely studied, yet the extraction of wood for fuel can impact Forest structure, function and biodiversity. We assessed the effects of fuelwood collection on the Forest of Mt Elgon National Park (Uganda). We interviewed 192 households about fuelwood use and surveyed dead wood in 81 plots inside the park. Forest was the most important source of fuelwood. People collected on average between 1.1 and 2.0m3 of fuelwood per capita per year. Other activities involving wood fuel extraction from the Forest included illegal commercial fuelwood harvesting and charcoal making. Quantities of dead wood were affected by fuelwood collection up to at least 1000m inside the boundary of the park. Depletion of dead wood inside the park was greater in the sites where the population was most dense. Nevertheless, people who planted more trees on their own land perceived land outside the park to be important and valued old growth Forest less as a source of fuelwood. Highly-preferred tree species were most depleted, particularly when they were also valued timber trees, such as Prunus africana, Popocarpus milianjianus, Allophylus abyssinicus and Olea spp. Locally dominant species were less affected. Impacts varied among sites depending on the history of agricultural encroachment and locally-specific Forest uses, e.g. harvesting of trees for poles or use of the Forest land for grazing. Allowing the collection of dead wood in Forests is double-edged as it creates opportunities for other activities that are more damaging. Demand for wood fuel from tropical Forests is still likely to grow in the foreseeable future. Our results indicate that the Forest may become more degraded as a result, with negative consequences for the people who depend on the Forest and for conservation. Research into local ecological and cultural contexts and perceptions concerning costs and benefits can help devise more sustainable management options, including alternative sources of fuel.
Kenneth E. Giller - One of the best experts on this subject based on the ideXlab platform.
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fuelwood collection and its impacts on a protected tropical Mountain Forest in uganda
Forest Ecology and Management, 2015Co-Authors: Marieke Sassen, Douglas Sheil, Kenneth E. GillerAbstract:Local communities who live close to protected tropical Forests often depend on them for woodfuel, their main source of energy. The impacts of fuelwood extraction in humid Forests are rarely studied, yet the extraction of wood for fuel can impact Forest structure, function and biodiversity. We assessed the effects of fuelwood collection on the Forest of Mt Elgon National Park (Uganda). We interviewed 192 households about fuelwood use and surveyed dead wood in 81 plots inside the park. Forest was the most important source of fuelwood. People collected on average between 1.1 and 2.0m3 of fuelwood per capita per year. Other activities involving wood fuel extraction from the Forest included illegal commercial fuelwood harvesting and charcoal making. Quantities of dead wood were affected by fuelwood collection up to at least 1000m inside the boundary of the park. Depletion of dead wood inside the park was greater in the sites where the population was most dense. Nevertheless, people who planted more trees on their own land perceived land outside the park to be important and valued old growth Forest less as a source of fuelwood. Highly-preferred tree species were most depleted, particularly when they were also valued timber trees, such as Prunus africana, Popocarpus milianjianus, Allophylus abyssinicus and Olea spp. Locally dominant species were less affected. Impacts varied among sites depending on the history of agricultural encroachment and locally-specific Forest uses, e.g. harvesting of trees for poles or use of the Forest land for grazing. Allowing the collection of dead wood in Forests is double-edged as it creates opportunities for other activities that are more damaging. Demand for wood fuel from tropical Forests is still likely to grow in the foreseeable future. Our results indicate that the Forest may become more degraded as a result, with negative consequences for the people who depend on the Forest and for conservation. Research into local ecological and cultural contexts and perceptions concerning costs and benefits can help devise more sustainable management options, including alternative sources of fuel.
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fuelwood collection and its impacts on a protected tropical Mountain Forest in uganda
Forest Ecology and Management, 2015Co-Authors: Marieke Sassen, Douglas Sheil, Kenneth E. GillerAbstract:Local communities who live close to protected tropical Forests often depend on them for woodfuel, their main source of energy. The impacts of fuelwood extraction in humid Forests are rarely studied, yet the extraction of wood for fuel can impact Forest structure, function and biodiversity. We assessed the effects of fuelwood collection on the Forest of Mt Elgon National Park (Uganda). We interviewed 192 households about fuelwood use and surveyed dead wood in 81 plots inside the park. Forest was the most important source of fuelwood. People collected on average between 1.1 and 2.0m3 of fuelwood per capita per year. Other activities involving wood fuel extraction from the Forest included illegal commercial fuelwood harvesting and charcoal making. Quantities of dead wood were affected by fuelwood collection up to at least 1000m inside the boundary of the park. Depletion of dead wood inside the park was greater in the sites where the population was most dense. Nevertheless, people who planted more trees on their own land perceived land outside the park to be important and valued old growth Forest less as a source of fuelwood. Highly-preferred tree species were most depleted, particularly when they were also valued timber trees, such as Prunus africana, Popocarpus milianjianus, Allophylus abyssinicus and Olea spp. Locally dominant species were less affected. Impacts varied among sites depending on the history of agricultural encroachment and locally-specific Forest uses, e.g. harvesting of trees for poles or use of the Forest land for grazing. Allowing the collection of dead wood in Forests is double-edged as it creates opportunities for other activities that are more damaging. Demand for wood fuel from tropical Forests is still likely to grow in the foreseeable future. Our results indicate that the Forest may become more degraded as a result, with negative consequences for the people who depend on the Forest and for conservation. Research into local ecological and cultural contexts and perceptions concerning costs and benefits can help devise more sustainable management options, including alternative sources of fuel.
Victoria Ochoa - One of the best experts on this subject based on the ideXlab platform.
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human impacts drive Forest structure and diversity insights from mediterranean Mountain Forest dominated by abies pinsapo boiss
European Journal of Forest Research, 2011Co-Authors: Juan Carlos Linares, Jose A Carreira, Victoria OchoaAbstract:Environmental factors and land-use are likely interacting to drive Forest structure and species diversity, making it difficult to disentangle their separate impacts. Both components influence the resilience and stability of Mountain Forests in the Mediterranean Basin, since secular land-use has shaped stands structure and Forests dynamics are constrained to the environment. Approaches covering environmental factors and contrasting land-uses are still needed to understand their implications on Forest dynamics. We investigated patterns of environmental variables, stand structure and biodiversity in Forest dominated by Abies pinsapo for 61 stands over their whole range. In addition, since land-use by local inhabitant could be a key factor, logging intensity was quantified by stumps basal area and recent land-use history was investigated. Partial redundancy analysis (pRDA) was conducted to assess to which degree the structural attributes are related to environmental characteristics and/or the land-use in the main A. pinsapo Forests. Environmental characteristics accounted for 13% of the total variance, while the contrasting land-use (Spain vs. Morocco) and the stumps basal area, as indicator of human logging, accounted for 23% of the total variance. Trees species diversity was near 5 times higher in Moroccan stands than in stands from south Spain. According to recent human logging, Spanish stands have been strictly protected, but Moroccan stands showed widespread axe-logging by local inhabitant over the smaller tree sizes. Our results suggest that the preservation of a minor perturbation regimen by local populations enhance and help to preserve the whole biodiversity of this relict habitat.
Paula Regina Corain Lopes - One of the best experts on this subject based on the ideXlab platform.
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a portable low cost relaxed eddy accumulation rea system for quantifying ecosystem level fluxes of volatile organics
Atmospheric Environment, 2020Co-Authors: C Sarkar, Andrew Turnipseed, S Shertz, T Karl, Mark J Potosnak, Jianhui Bai, D Serca, Damien Bonal, Benoit Burban, Paula Regina Corain LopesAbstract:Abstract Quantification of biogenic volatile organic compound (BVOC) fluxes into the atmosphere is crucial to understand their role in atmospheric oxidation and biogeochemical cycles. BVOC flux measurements were carried out in nine Forest ecosystems using a relaxed eddy accumulation (REA) based sampling system, which is easily transportable, simple to operate and designed to be low-cost and therefore can easily be deployed at multiple remote locations. The REA measurements were carried out during daytime between 06:00 and 18:30 (Local Time) with a flux averaging period of 30 min. A detailed description of the REA sampling setup, operational procedure and validation by comparison with full eddy covariance (EC) BVOC flux measurements is provided. BVOC flux measurements from established long-term carbon and water flux tower sites in nine Forest ecosystems are compared including Manitou Forest Observatory in Colorado, USA (pine woodland Forest), Niwot Ridge AmeriFlux site in Colorado, USA (subalpine Forest), Deer Canyon Preserve in New Mexico, USA (pinyon-juniper Forest), Lei bamboo Forest site near Taihuyuan, China, Qianyanzhou ChinaFLUX site in China (pine Forest), Baskett Wildfire Refuge MOFlux site in Missouri, USA (deciduous oak Forest), University of Michigan Biological Station PROPHET site in Michigan, USA (mixed deciduous Forest), Changbai Mountain Forest Research Station in China (mixed deciduous Forest) and the Guyaflux site (GF-Guy) in French Guiana (tropical rainForest). BVOC flux measurements using our REA setup confirm dominance of 2,3,2- methylbutenol (2,3,2-MBO) at the Manitou Forest Observatory and Niwot Ridge sites in Colorado. Monoterpene fluxes measured by REA showed good agreement (within ±10%) with monoterpene fluxes measured by PTR-MS at the Manitou Forest Observatory. The MOFlux site in Missouri was dominated by isoprene emissions (average flux of ∼9.5 mg m−2 h−1) whereas the Deer Canyon site was dominated by α-pinene emissions (average flux ∼ 0.73 mg m−2 h−1). Mixed deciduous Forest sites at the PROPHET Station in Michigan and Changbai Mountain Forest Research Station in China primarily emitted isoprene along with some α-pinene, β-pinene and d-Limonene. Isoprene and α-pinene were the dominant BVOCs emitted from the subtropical Lei bamboo plantation at the Taihuyuan site in China while the pine Forest site at Qianyanzhou in China were dominated by α-pinene emissions along with significant isoprene. BVOC measurements across different seasons (during 2009–2011) at a tropical Forest site in French Guiana (Guyaflux site) revealed the dominance of isoprene emissions during all seasons. Irrespective of the type of the Forest ecosystem, α-pinene was among the dominant monoterpenes emitted from all nine Forests.