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Sven Dänicke - One of the best experts on this subject based on the ideXlab platform.
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The effect of free air Carbon Dioxide Enrichment and nitrogen fertilisation on the chemical composition and nutritional value of wheat and barley grain
Archives of animal nutrition, 2013Co-Authors: Stefanie Wroblewitz, Hans-joachim Weigel, Liane Hüther, Remigius Manderscheid, Hermann Wätzig, Sven DänickeAbstract:A rising atmospheric CO2 concentration might influence the nutrient composition of feedstuffs and consequently the nutritional value for livestock. The present study investigates the effects of atmospheric CO2 Enrichment on the chemical composition and nutritional value of winter wheat cv. “Batis” and winter barley cv. “Theresa”. Both cereals were grown at two different atmospheric CO2 concentrations (ambient CO2 [AMBI]: 380 ppm and enriched CO2 [free air Carbon Dioxide Enrichment, FACE]: 550 ppm) for two growing seasons. The influence of two different nitrogen (N) fertilisation levels (adequate N supply [N100] and nearly 50% of adequate N supply [N50]) were studied as well. A significant effect was observed for the crude protein content, which declined at FACE condition in a range of 8–16 g kg−1 in wheat and of 10–20 g kg−1 in barley. A reduced N fertilisation level resulted in a strong reduction of crude protein concentration in both cereal species. In wheat, a decrease in N supply significantly enhance...
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Effects of the thermal environment on metabolism of deoxynivalenol and thermoregulatory response of sheep fed on corn silage grown at enriched atmospheric Carbon Dioxide and drought
Mycotoxin Research, 2012Co-Authors: Malte Lohölter, Hans-joachim Weigel, Ulrich Meyer, Martin Erbs, Gerhard Flachowsky, Susanne Döll, Remy Manderscheid, Martin Höltershinken, Sven DänickeAbstract:Future livestock production is likely to be affected by both rising ambient temperatures and indirect effects mediated by modified growth conditions of feed plants such as increased atmospheric CO_2 concentrations and drought. Corn was grown at elevated CO_2 concentrations of 550 ppm and drought stress using free air Carbon Dioxide Enrichment technology. Whole plant silages were generated and fed to sheep kept at three climatic treatments. Differential blood count was performed. Plasma DON and de-epoxy-DON concentration were measured. Warmer environment increased rectal and skin temperatures and respiration rates ( p
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Effects of free air Carbon Dioxide Enrichment and drought stress on the feed value of maize silage fed to sheep at different thermal regimes
Archives of animal nutrition, 2012Co-Authors: Malte Lohölter, Hans-joachim Weigel, Remigius Manderscheid, Ulrich Meyer, Martin Erbs, Gerhard Flachowsky, Sven DänickeAbstract:Information about the effects of rising atmospheric CO2 concentration and drought on the feed value of maize silage and interactions with the thermal environment during feeding is limited. A free air Carbon Dioxide Enrichment facility was operated in a maize field to generate an elevated CO2 concentration of 550 ppm. Drought was induced by the exclusion of precipitation in one half of all experimental plots. Plants were harvested, chopped and ensiled. In a balance experiment on sheep, the nutrient digestibility was determined for three climatic treatments (temperate, temperature humidity index (THI) 57-63; mild heat, THI 68-71; severe heat, THI 75-80). The CO2 concentration and drought did not alter the crude nutrient content of silage dry matter (DM) or nutrient and organic matter (OM) digestibility. Drought increased the concentration of deoxynivalenol (DON, p < 0.001). The drought-associated increase of DON was reduced by CO2 Enrichment (p = 0.003). The lowest digestibility of acid detergent fibre (p = 0.024) and neutral detergent fibre (p = 0.005) was observed during the coldest climate. OM digestibility increased during mild heat (p = 0.023). This study did not indicate considerable alterations of the feed value of maize silage due to increased atmospheric CO2 and drought. Enriched CO2 may decrease DON contaminations during drought. The thermal environment during the balance experiment did not interact with feeding maize silage grown under elevated CO2, but may affect cell wall and OM digestibility.
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Effects of free air Carbon Dioxide Enrichment and drought stress on the rumen in sacco degradability of corn silage harvested at various times
Landbauforschung Volkenrode, 2012Co-Authors: Malte Lohölter, Hans-joachim Weigel, Remigius Manderscheid, Ulrich Meyer, Martin Erbs, Gerhard Flachowsky, Peter Lebzien, Sven DänickeAbstract:The present study investigated the effects of increased atmospheric CO2 concentration, drought stress and har-vest date on the rumen in sacco dry matter degradabil-ity of corn silage. A free air Carbon Dioxide Enrichment facility (FACE) was operated in a field to generate a CO2 concentration of 550 ppm in three treatment plots. Three plots served as control. All plots were divided into two semicircles to produce drought stress by the exclusion of precipitation in one half each. Corn plants were harvested at three dates (26 August, 12 September, 29 September 2008), chopped, ensiled, dried and ground. The in sacco degradability after 2, 4, 8, 16, 24, 48 and 96 h was evalu-ated using six non-lactating rumen cannuled Holstein cows. The potential dry matter degradability, the sum of water soluble and degradable unsoluble fraction, was not affected by CO2 elevation. A low CO2 effect below 1 % unit was found on the effective degradability, which is cal-culated in consideration of an assumed rate of passage from the rumen. Drought did not alter the potential de-gradability, but the kinetics of dry matter degradation and decreased the effective degradability by 2 % units. Harvest date affected all degradation parameters. Later harvest was related to an increased potential but reduced effec-tive degradability. The potential degradability had close inverse relationships to neutral detergent fibre concentra-tion (r = -0.74, P < 0.01) but was positively correlated to starch (r = 0.80, P < 0.01) and DM (r = 0.80, P < 0.01). The correlations between effective degradability and crude nutrients were generally not significant. Harvest date will remain an important factor influencing the feed value of corn silage, but the effects of elevated CO2 concentration and drought stress did not indicate considerable impacts.
Keith F. Lewin - One of the best experts on this subject based on the ideXlab platform.
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characteristics of free air Carbon Dioxide Enrichment of a northern temperate mature forest
Global Change Biology, 2020Co-Authors: Kris Hart, J. Nagy, Giulio Curioni, Phillip J. Blaen, Nicholas J. Harper, Peter Miles, Keith F. Lewin, Edward J. Bannister, Xiaoming Cai, Rick M ThomasAbstract:In 2017, the Birmingham Institute of Forest Research (BIFoR) began to conduct Free Air Carbon Dioxide Enrichment (FACE) within a mature broadleaf deciduous forest situated in the United Kingdom. BIFoR FACE employs large-scale infrastructure, in the form of lattice towers, forming 'arrays' which encircle a forest plot of ~30 m diameter. BIFoR FACE consists of three treatment arrays to elevate local CO2 concentrations (e[CO2 ]) by +150 µmol/mol. In practice, acceptable operational Enrichment (ambient [CO2 ] + e[CO2 ]) is ±20% of the set point 1-min average target. There are a further three arrays that replicate the infrastructure and deliver ambient air as paired controls for the treatment arrays. For the first growing season with e[CO2 ] (April to November 2017), [CO2 ] measurements in treatment and control arrays show that the target concentration was successfully delivered, that is: +147 ± 21 µmol/mol (mean ± SD) or 98 ± 14% of set point Enrichment target. e[CO2 ] treatment was accomplished for 97.7% of the scheduled operation time, with the remaining time lost due to engineering faults (0.6% of the time), CO2 supply issues (0.6%) or adverse weather conditions (1.1%). CO2 demand in the facility was driven predominantly by wind speed and the formation of the deciduous canopy. Deviations greater than 10% from the ambient baseline CO2 occurred 80 µmol/mol (i.e. >53% of the treatment increment) into control arrays accounted for <0.1% of the Enrichment period. The median [CO2 ] values in reconstructed three-dimensional [CO2 ] fields show Enrichment somewhat lower than the target but still well above ambient. The data presented here provide confidence in the facility setup and can be used to guide future next-generation forest FACE facilities built into tall and complex forest stands.
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Characteristics of free air Carbon Dioxide Enrichment of a northern temperate mature forest.
Global change biology, 2019Co-Authors: Kris Hart, J. Nagy, Giulio Curioni, Phillip J. Blaen, Nicholas J. Harper, Peter Miles, Keith F. Lewin, Edward J. Bannister, Xiaoming Cai, Rick ThomasAbstract:In 2017, the Birmingham Institute of Forest Research (BIFoR) began to conduct Free Air Carbon Dioxide Enrichment (FACE) within a mature broadleaf deciduous forest situated in the United Kingdom. BIFoR FACE employs large-scale infrastructure, in the form of lattice towers, forming 'arrays' which encircle a forest plot of ~30 m diameter. BIFoR FACE consists of three treatment arrays to elevate local CO2 concentrations (e[CO2 ]) by +150 µmol/mol. In practice, acceptable operational Enrichment (ambient [CO2 ] + e[CO2 ]) is ±20% of the set point 1-min average target. There are a further three arrays that replicate the infrastructure and deliver ambient air as paired controls for the treatment arrays. For the first growing season with e[CO2 ] (April to November 2017), [CO2 ] measurements in treatment and control arrays show that the target concentration was successfully delivered, that is: +147 ± 21 µmol/mol (mean ± SD) or 98 ± 14% of set point Enrichment target. e[CO2 ] treatment was accomplished for 97.7% of the scheduled operation time, with the remaining time lost due to engineering faults (0.6% of the time), CO2 supply issues (0.6%) or adverse weather conditions (1.1%). CO2 demand in the facility was driven predominantly by wind speed and the formation of the deciduous canopy. Deviations greater than 10% from the ambient baseline CO2 occurred 80 µmol/mol (i.e. >53% of the treatment increment) into control arrays accounted for
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design and application of a free air Carbon Dioxide Enrichment facility
Agricultural and Forest Meteorology, 1994Co-Authors: Keith F. Lewin, G.r. Hendrey, J. Nagy, R L LamorteAbstract:Growth chambers and other enclosures used in plant physiology and growth studies tend to introduce chamber effects that alter the microclimate around the plants compared with the natural environment. A free-air (chamberless) Carbon Dioxide Enrichment (FACE) system has been developed by Brookhaven National Laboratory (BNL) to provide controlled fumigation conditions while minimizing the potential to impose a discernible chamber effect. This system is capable of exposing large numbers of field-grown plants to elevated levels of atmospheric Carbon Dioxide (CO2) from seedling emergence until physiologic maturity. A FACE User Facility was established at the Maricopa Agricultural Center, University of Arizona, for continuous Enrichment of CO2 at a set point of 550 μmol mol−1 during daylight hours throughout the cotton crop growing seasons of 1989–1991. The facility consisted of four circular BNL FACE arrays and associated equipment placed in a commercial cotton plantation. FACE array diameters of 23, 25, and 27 m were tested. The FACE facility included the ability to operate the experimental plots under two watering regimes using an automated, sub-surface irrigation system. CO2 was stored in a 48 000 kg receiver and vaporized with a heat exchanger that used water at ambient temperature as the energy source. The 1 min average CO2 concentration was held to within ±20% of the set point more than 98% of the time that the arrays were operating during all three seasons. In 1991, the long term average CO2 concentration measured at 63 points throughout the volume of a 20 m diameter experimental plot (ground to canopy top) centered within a 25 m diameter FACE array was 568 μmol mol−1. All of the FACE arrays operated for more than 99% of the planned experimental period in 1991. These 3 years of operation have demonstrated that the BNL FACE technology can be used as a basis for a large scale facility devoted to studying the fate of Carbon in the terrestrial environment.
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free air Carbon Dioxide Enrichment development progress results
Plant Ecology, 1993Co-Authors: G.r. Hendrey, Keith F. Lewin, J. NagyAbstract:Credible predictions of climate change depend in part on predictions of future CO2 concentrations in the atmosphere. Terrestrial plants are a large sink for atmospheric CO2 and the sink rate is influenced by the atmospheric CO2 concentration. Reliable field experiments are needed to evaluate how terrestrial plants will adjust to increasing CO2 and thereby influence the rate of change of atmospheric CO2. Brookhaven National Laboratory (BNL) has developed a unique Free-Air CO2 Enrichment (FACE) system for a cooperative research program sponsored by the U.S. Department of Energy and U.S. Department of Agriculture, currently operating as the FACE User Facility at the Maricopa Agricultural Center (MAC) of the University of Arizona. The BNL FACE system is a tool for studying the effects of CO2 Enrichment on vegetation and natural ecosystems, and the exchange of Carbon between the biosphere and the atmosphere, in open-air settings without any containment. The FACE system provides stable control of CO2 at 550 ppm ± 10%, based on 1-min averages, over 90% of the time. In 1990, this level of control was achieved over an area as large as 380 m2, at an annual operating cost of $668 m−2. During two field seasons of Enrichment with cotton (Gossypium hirsutum) as the test plant, Enrichment to 550 ppm CO2 resulted in significant increases in photosynthesis and biomass of leaves, stems and roots, reduced evapotranspiration, and changes in root morphology. In addition, soil respiration increased and evapotranspiration decreased.
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brookhaven national laboratory free air Carbon Dioxide Enrichment facility
Critical Reviews in Plant Sciences, 1992Co-Authors: Keith F. Lewin, G.r. Hendrey, Zbigniew KolberAbstract:When evaluating the effects of gases on crops, forests or other ecosystems, the experimenter is faced with the problem of trying to produce an exposure regime in which only the variables chosen to be investigated are altered, while other features of the remaining edaphic environment remain in a natural state. This type of experiment has often been hampered by an inability to create an experimental environment free of artifacts introduced by the structures and equipment used to expose the target ecosystem to the test gas. These are generally described as {open_quotes}chamber effects{close_quotes} and include changes in wind velocity, humidity, temperature, light quality or intensity, and soil variables. In the quest for a more realistic experimental design, researchers have moved their plant fumigation studies from the highly controlled and unnatural environment of the greenhouse or growth chamber to open-top chambers. The primary benefit of this shift has been to reduce experimental artifacts associated with soil variables. Many of the other limitations of chambers have remained. 7 refs., 3 figs.
Gang Liu - One of the best experts on this subject based on the ideXlab platform.
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An indica rice genotype showed a similar yield enhancement to that of hybrid rice under free air Carbon Dioxide Enrichment
Scientific reports, 2015Co-Authors: Chunwu Zhu, Dan Wang, Jianguo Zhu, Gang LiuAbstract:Since 1959, the concentrations of atmospheric Carbon Dioxide [CO2] have increased from approximately 318 to 400 μmol mol−1 and, depending on the anthropogenic emission rates, may reach 1000 μmol mol−1 by the end of the century1. Because the photosynthetic rate in C3 species under the current levels of ambient [CO2] is still below physiological saturation levels, it is anticipated that photosynthesis, and consequently productivity, for most crops will be stimulated by the higher atmospheric [CO2]2. In theory, an increase in [CO2] from 380 μmol mol−1 to 550 μmol mol−1 projected for the year 2050 would increase C3 photosynthesis by 38%3, as indicated by many experimental and analytical studies4,5. Many early FACE studies have shown that rice yield increases (9–15%) were lower than expected due to photosynthetic acclimation5,6,7,8. In addition, researchers have found marked differences among rice cultivar responses to elevated [CO2]9,10,11,12. Hence, active selection and breeding for high CO2 responsiveness among rice varieties may provide a simple and direct strategy for increasing global yields and maintaining food security with climate change, but this potential has not received sufficient attention until recently13. China rice-FACE studies have already revealed hybrid rice genotypes with a greater yield enhancement (above 30%) under elevated [CO2] than conventional rice cultivars9,11. Previous FACE studies in Japan and China previously demonstrated that japonica rice exhibits a weak response to elevated [CO2]5,6,7,8. Therefore, we hope to find an indica rice genotype that has a similarly high enhancement under elevated CO2 as that exhibited by hybrid rice and that can be used under future climatic conditions. Yangdao 6 Hao has large panicles, a high yield potential, resistance to disease and pathogens, and an anti-lodging ability, which suggest that this cultivar may be an important gene resource for rice breeding14. Hence, we chose this cultivar as the study subject. The aim of this study was to investigate whether the indica rice under consideration has a similarly strong response to elevated [CO2] as hybrid rice using FACE (free air Carbon Dioxide Enrichment) treatment.
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Responses of rice (Oryza sativa) growth and its C, N and P composition to FACE (free-air Carbon Dioxide Enrichment) and N, P fertilization
Ying yong sheng tai xue bao = The journal of applied ecology, 2002Co-Authors: Zubin Xie, Jianguo Zhu, Gang Liu, Yali Zhang, Yong Han, Qing Zeng, Zucong CaiAbstract:FACE (Free-air Carbon Dioxide Enrichment) was used to study the effects of elevated CO 2 on rice (Oryza sativa) growth,tissue C/N,N and P concentration and uptake at different development stages under two N and two P levels. Results showed that elevated CO 2 increased dry matter accumulation in rice stem, ear and root. Leaf dry matter was increased at tillering stage and no significant effect was found at jointing, heading and ripening stages. N concentration of stem and leaf was decreased. Ear N concentration at heading stage was increased but was decreased at ripening stage. No significant effect was found on root N concentration at tillering stage but root N concentration at jointing, heading and ripening was decreased. Leaf P concentration at jointing, heading and ripening was increased but no significant effect was found on P concentration in stem, ear and root. C content in various tissues changed unremarkably and the ratio of C over N (C/N) was increased. Elevated CO 2 significantly increased P uptake in aboveground tissues; and increased N uptake, but the difference was not statistically significant. N and P fertilization had no significant effect on various tissue dry biomass. Tissue N content at higher N fertilization was higher than at lower N fertilization but no such effect of P fertilization on tissue P content was found. At higher N fertilization, elevated CO 2 increased the ratio of below-ground biomass over above-ground biomass at ripening stage. Possible reasons are discussed for the differences of tissue N and P content and the ratio of below-ground biomass over above-ground biomass between elevated and ambient atmospheric CO 2 concentrations.
Christian Korner - One of the best experts on this subject based on the ideXlab platform.
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through enhanced tree dynamics Carbon Dioxide Enrichment may cause tropical forests to lose Carbon
Philosophical Transactions of the Royal Society B, 2004Co-Authors: Christian KornerAbstract:The fixation and storage of C by tropical forests, which contain close to half of the globe's biomass C, may be affected by elevated atmospheric CO2 concentration. Classical theoretical approaches assume a uniform stimulation of photosynthesis and growth across taxa. Direct assessments of the C balance either by flux studies or by repeated forest inventories also suggest a current net uptake, although magnitudes sometimes exceed those missing required to balance the global C cycle. Reasons for such discrepancies may lie in the nature of forest dynamics and in differential responses of taxa or plant functional types. In this contribution I argue that CO2 Enrichment may cause forests to become more dynamic and that faster tree turnover may in fact convert a stimulatory effect of elevated CO2 on photosynthesis and growth into a long-term net biomass C loss by favouring shorter-lived trees of lower wood density. At the least, this is a scenario that deserves inclusion into long-term projections of the C relations of tropical forests. Species and plant functional type specific responses ('biodiversity effects') and forest dynamics need to be accounted for in projections of future C storage and cycling in tropical forests.
Hans-joachim Weigel - One of the best experts on this subject based on the ideXlab platform.
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The effect of free air Carbon Dioxide Enrichment and nitrogen fertilisation on the chemical composition and nutritional value of wheat and barley grain
Archives of animal nutrition, 2013Co-Authors: Stefanie Wroblewitz, Hans-joachim Weigel, Liane Hüther, Remigius Manderscheid, Hermann Wätzig, Sven DänickeAbstract:A rising atmospheric CO2 concentration might influence the nutrient composition of feedstuffs and consequently the nutritional value for livestock. The present study investigates the effects of atmospheric CO2 Enrichment on the chemical composition and nutritional value of winter wheat cv. “Batis” and winter barley cv. “Theresa”. Both cereals were grown at two different atmospheric CO2 concentrations (ambient CO2 [AMBI]: 380 ppm and enriched CO2 [free air Carbon Dioxide Enrichment, FACE]: 550 ppm) for two growing seasons. The influence of two different nitrogen (N) fertilisation levels (adequate N supply [N100] and nearly 50% of adequate N supply [N50]) were studied as well. A significant effect was observed for the crude protein content, which declined at FACE condition in a range of 8–16 g kg−1 in wheat and of 10–20 g kg−1 in barley. A reduced N fertilisation level resulted in a strong reduction of crude protein concentration in both cereal species. In wheat, a decrease in N supply significantly enhance...
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Effects of the thermal environment on metabolism of deoxynivalenol and thermoregulatory response of sheep fed on corn silage grown at enriched atmospheric Carbon Dioxide and drought
Mycotoxin Research, 2012Co-Authors: Malte Lohölter, Hans-joachim Weigel, Ulrich Meyer, Martin Erbs, Gerhard Flachowsky, Susanne Döll, Remy Manderscheid, Martin Höltershinken, Sven DänickeAbstract:Future livestock production is likely to be affected by both rising ambient temperatures and indirect effects mediated by modified growth conditions of feed plants such as increased atmospheric CO_2 concentrations and drought. Corn was grown at elevated CO_2 concentrations of 550 ppm and drought stress using free air Carbon Dioxide Enrichment technology. Whole plant silages were generated and fed to sheep kept at three climatic treatments. Differential blood count was performed. Plasma DON and de-epoxy-DON concentration were measured. Warmer environment increased rectal and skin temperatures and respiration rates ( p
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Effects of free air Carbon Dioxide Enrichment and drought stress on the feed value of maize silage fed to sheep at different thermal regimes
Archives of animal nutrition, 2012Co-Authors: Malte Lohölter, Hans-joachim Weigel, Remigius Manderscheid, Ulrich Meyer, Martin Erbs, Gerhard Flachowsky, Sven DänickeAbstract:Information about the effects of rising atmospheric CO2 concentration and drought on the feed value of maize silage and interactions with the thermal environment during feeding is limited. A free air Carbon Dioxide Enrichment facility was operated in a maize field to generate an elevated CO2 concentration of 550 ppm. Drought was induced by the exclusion of precipitation in one half of all experimental plots. Plants were harvested, chopped and ensiled. In a balance experiment on sheep, the nutrient digestibility was determined for three climatic treatments (temperate, temperature humidity index (THI) 57-63; mild heat, THI 68-71; severe heat, THI 75-80). The CO2 concentration and drought did not alter the crude nutrient content of silage dry matter (DM) or nutrient and organic matter (OM) digestibility. Drought increased the concentration of deoxynivalenol (DON, p < 0.001). The drought-associated increase of DON was reduced by CO2 Enrichment (p = 0.003). The lowest digestibility of acid detergent fibre (p = 0.024) and neutral detergent fibre (p = 0.005) was observed during the coldest climate. OM digestibility increased during mild heat (p = 0.023). This study did not indicate considerable alterations of the feed value of maize silage due to increased atmospheric CO2 and drought. Enriched CO2 may decrease DON contaminations during drought. The thermal environment during the balance experiment did not interact with feeding maize silage grown under elevated CO2, but may affect cell wall and OM digestibility.
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Effects of free air Carbon Dioxide Enrichment and drought stress on the rumen in sacco degradability of corn silage harvested at various times
Landbauforschung Volkenrode, 2012Co-Authors: Malte Lohölter, Hans-joachim Weigel, Remigius Manderscheid, Ulrich Meyer, Martin Erbs, Gerhard Flachowsky, Peter Lebzien, Sven DänickeAbstract:The present study investigated the effects of increased atmospheric CO2 concentration, drought stress and har-vest date on the rumen in sacco dry matter degradabil-ity of corn silage. A free air Carbon Dioxide Enrichment facility (FACE) was operated in a field to generate a CO2 concentration of 550 ppm in three treatment plots. Three plots served as control. All plots were divided into two semicircles to produce drought stress by the exclusion of precipitation in one half each. Corn plants were harvested at three dates (26 August, 12 September, 29 September 2008), chopped, ensiled, dried and ground. The in sacco degradability after 2, 4, 8, 16, 24, 48 and 96 h was evalu-ated using six non-lactating rumen cannuled Holstein cows. The potential dry matter degradability, the sum of water soluble and degradable unsoluble fraction, was not affected by CO2 elevation. A low CO2 effect below 1 % unit was found on the effective degradability, which is cal-culated in consideration of an assumed rate of passage from the rumen. Drought did not alter the potential de-gradability, but the kinetics of dry matter degradation and decreased the effective degradability by 2 % units. Harvest date affected all degradation parameters. Later harvest was related to an increased potential but reduced effec-tive degradability. The potential degradability had close inverse relationships to neutral detergent fibre concentra-tion (r = -0.74, P < 0.01) but was positively correlated to starch (r = 0.80, P < 0.01) and DM (r = 0.80, P < 0.01). The correlations between effective degradability and crude nutrients were generally not significant. Harvest date will remain an important factor influencing the feed value of corn silage, but the effects of elevated CO2 concentration and drought stress did not indicate considerable impacts.
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Soil Carbon isotopic composition and soil Carbon content in an agroecosystem during six years of Free Air Carbon Dioxide Enrichment (FACE).
Isotopes in environmental and health studies, 2008Co-Authors: Anette Giesemann, Hans-joachim WeigelAbstract:The Free Air Carbon Dioxide Enrichment (FACE) experiment conducted at the Federal Agricultural Research Centre (FAL) in Braunschweig in an arable crop rotation (total duration six years) allowed us to trace Carbon (C) input in the soil C pool, as the CO2, used in the experiment to increase the atmospheric CO2 concentration, was depleted in 13C. Accurate assessment of the C input by means of stable C isotope analysis requires detailed knowledge on the spatial distribution of both the C isotopic composition and the C content in the soil C. Assumed changes in these parameters were examined. CO2 Enrichment treatment over a six year period resulted in a clear trend towards an increase of soil C content in the uppermost 10 cm of soil. About 4.9% of the soil C present under ambient air conditions, and 10.7% present under elevated CO2 conditions were determined as new input. However, the results are not statistically significant yet. †Revised version of a paper presented at the 30th Annual Meeting of the German A...