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- ItemImpacts of enhanced weathering on biomass production for negative emission technologies and soil hydrology(Katlenburg-Lindau [u.a.] : Copernicus, 2020) De Oliveira Garcia, Wagner; Amann, Thorben; Hartmann, Jens; Karstens, Kristine; Popp, Alexander; Boysen, Lena R.; Smith, Pete; Goll, DanielLimiting global mean temperature changes to well below 2 Ā°C likely requires a rapid and large-scale deployment of negative emission technologies (NETs). Assessments so far have shown a high potential of biomass-based terrestrial NETs, but only a few assessments have included effects of the commonly found nutrient-deficient soils on biomass production. Here, we investigate the deployment of enhanced weathering (EW) to supply nutrients to areas of afforestation-reforestation and naturally growing forests (AR) and bioenergy grasses (BG) that are deficient in phosphorus (P), besides the impacts on soil hydrology. Using stoichiometric ratios and biomass estimates from two established vegetation models, we calculated the nutrient demand of AR and BG. Insufficient geogenic P supply limits C storage in biomass. For a mean P demand by AR and a lowgeogenic-P-supply scenario, AR would sequester 119 Gt C in biomass; for a high-geogenic-P-supply and low-AR-Pdemand scenario, 187 Gt C would be sequestered in biomass; and for a low geogenic P supply and high AR P demand, only 92 GtC would be accumulated by biomass. An average amount of ā¼ 150 Gt basalt powder applied for EW would be needed to close global P gaps and completely sequester projected amounts of 190 Gt C during the years 2006-2099 for the mean AR P demand scenario (2-362 Gt basalt powder for the low-AR-P-demand and for the high-AR-P-demand scenarios would be necessary, respectively). The average potential of carbon sequestration by EW until 2099 is ā¼ 12 GtC (ā¼ 0:2-ā¼ 27 Gt C) for the specified scenarios (excluding additional carbon sequestration via alkalinity production). For BG, 8 kg basaltm2 a1 might, on average, replenish the exported potassium (K) and P by harvest. Using pedotransfer functions, we show that the impacts of basalt powder application on soil hydraulic conductivity and plant-Available water, to close predicted P gaps, would depend on basalt and soil texture, but in general the impacts are marginal. We show that EW could potentially close the projected P gaps of an AR scenario and nutrients exported by BG harvest, which would decrease or replace the use of industrial fertilizers. Besides that, EW ameliorates the soil's capacity to retain nutrients and soil pH and replenish soil nutrient pools. Lastly, EW application could improve plant-Available-water capacity depending on deployed amounts of rock powder - adding a new dimension to the coupling of land-based biomass NETs with EW. Ā© 2020 Royal Society of Chemistry. All rights reserved.
- ItemChanges in alpine plant growth under future climate conditions(MĆ¼nchen : European Geopyhsical Union, 2010) Rammig, A.; Jonas, T.; Zimmermann, N.E.; Rixen, C.Alpine shrub- and grasslands are shaped by extreme climatic conditions such as a long-lasting snow cover and a short vegetation period. Such ecosystems are expected to be highly sensitive to global environmental change. Prolonged growing seasons and shifts in temperature and precipitation are likely to affect plant phenology and growth. In a unique experiment, climatology and plant growth was monitored for almost a decade at 17 snow meteorological stations in different alpine regions along the Swiss Alps. Regression analyses revealed highly significant correlations between mean air temperature in May/June and snow melt out, onset of plant growth, and plant height. These correlations were used to project plant growth phenology for future climate conditions based on the gridded output of a set of regional climate models runs. Melt out and onset of growth were projected to occur on average 17 days earlier by the end of the century than in the control period from 1971ā2000 under the future climate conditions of the low resolution climate model ensemble. Plant height and biomass production were expected to increase by 77% and 45%, respectively. The earlier melt out and onset of growth will probably cause a considerable shift towards higher growing plants and thus increased biomass. Our results represent the first quantitative and spatially explicit estimates of climate change impacts on future growing season length and the respective productivity of alpine plant communities in the Swiss Alps.
- ItemDesigning Hierarchical ZSM-5 Materials for Improved Production of LPG Olefins in the Catalytic Cracking of Triglycerides(New York, NY : Hindawi, 2019) Vu, Xuan Hoan; Armbruster, UdoLPG olefins (propene and butenes) are key building blocks in the petrochemical industry whose demand has been expanding steadily in recent years. The use of FCC (fluid catalytic cracking) units for conversion of triglycerides is a promising option for the future to boost production of LPG olefins. However, a need for innovative cracking catalysts is rising due to the different nature between petroleum and biomass-derived feedstocks. In this study, series of hierarchical ZSM-5 materials, namely, mesoporous ZSM-5, nanosized ZSM-5, and composite ZSM-5 were prepared, aiming to enhance the production of LPG olefins along with transportation fuels. Mesoporous ZSM-5 materials were synthesized by the postsynthetic modifications involving base treatment and subsequent acid washing, whereas nanosized ZSM-5 and composite ZSM-5 were synthesized by the direct-synthetic routes for a comparative purpose. The obtained materials were characterized by XRD, FTIR, N2 sorption, TEM, AAS, ICP-AES, and NH3-TPD, and their catalytic performance was assessed in the cracking of triolein as a representative of triglycerides under FCC conditions. It was found that the subsequent strong acid washing step of alkaline treated ZSM-5 for removal of aluminum debris and external acid sites is needed to improve the catalytic performance. The resulting mesoporous ZSM-5 material shows higher yields of the desired products, i.e., gasoline and LPG olefins than its parent, commercial ZSM-5 at the almost complete conversion (ca. 90 wt.%). The selectivity toward LPG olefins is also enhanced over all the hierarchical ZSM-5 materials, particularly high for composite ZSM-5 (ca. 94 wt.%). The improved diffusion and lowered acidity of the hierarchical ZSM-5 materials might be responsible for their superior catalytic performance. Ā© 2019 Xuan Hoan Vu and Udo Armbruster.
- ItemThe global technical potential of bio-energy in 2050 considering sustainability constraints(Amsterdam : Elsevier, 2010) Haberl, H.; Beringer, T.; Bhattacharya, S.C.; Erb, K.-H.; Hoogwijk, M.Bio-energy, that is, energy produced from organic non-fossil material of biological origin, is promoted as a substitute for non-renewable (e.g., fossil) energy to reduce greenhouse gas (GHG) emissions and dependency on energy imports. At present, global bio-energy use amounts to approximately 50 EJ/yr, about 10% of humanity's primary energy supply. We here review recent literature on the amount of bio-energy that could be supplied globally in 2050, given current expectations on technology, food demand and environmental targets ('technical potential'). Recent studies span a large range of global bio-energy potentials from ā30 to over 1000 EJ/yr. In our opinion, the high end of the range is implausible because of (1) overestimation of the area available for bio-energy crops due to insufficient consideration of constraints (e.g., area for food, feed or nature conservation) and (2) too high yield expectations resulting from extrapolation of plot-based studies to large, less productive areas. According to this review, the global technical primary bio-energy potential in 2050 is in the range of 160-270 EJ/yr if sustainability criteria are considered. The potential of bio-energy crops is at the lower end of previously published ranges, while residues from food production and forestry could provide significant amounts of energy based on an integrated optimization ('cascade utilization') of biomass flows. Ā© 2010 Elsevier B.V.
- ItemCharacterization of Bathyarchaeota genomes assembled from metagenomes of biofilms residing in mesophilic and thermophilic biogas reactors(London : BioMed Central Ltd., 2018) Maus, I.; Rumming, M.; Bergmann, I.; Heeg, K.; Pohl, M.; Nettmann, E.; Jaenicke, S.; Blom, J.; PĆ¼hler, A.; SchlĆ¼ter, A.; Sczyrba, A.; Klocke, M.Background: Previous studies on the Miscellaneous Crenarchaeota Group, recently assigned to the novel archaeal phylum Bathyarchaeota, reported on the dominance of these Archaea within the anaerobic carbohydrate cycle performed by the deep marine biosphere. For the first time, members of this phylum were identified also in mesophilic and thermophilic biogas-forming biofilms and characterized in detail. Results: Metagenome shotgun libraries of biofilm microbiomes were sequenced using the Illumina MiSeq system. Taxonomic classification revealed that between 0.1 and 2% of all classified sequences were assigned to Bathyarchaeota. Individual metagenome assemblies followed by genome binning resulted in the reconstruction of five metagenome-assembled genomes (MAGs) of Bathyarchaeota. MAGs were estimated to be 65-92% complete, ranging in their genome sizes from 1.1 to 2.0 Mb. Phylogenetic classification based on core gene sets confirmed their placement within the phylum Bathyarchaeota clustering as a separate group diverging from most of the recently known Bathyarchaeota clusters. The genetic repertoire of these MAGs indicated an energy metabolism based on carbohydrate and amino acid fermentation featuring the potential for extracellular hydrolysis of cellulose, cellobiose as well as proteins. In addition, corresponding transporter systems were identified. Furthermore, genes encoding enzymes for the utilization of carbon monoxide and/or carbon dioxide via the Wood-Ljungdahl pathway were detected. Conclusions: For the members of Bathyarchaeota detected in the biofilm microbiomes, a hydrolytic lifestyle is proposed. This is the first study indicating that Bathyarchaeota members contribute presumably to hydrolysis and subsequent fermentation of organic substrates within biotechnological biogas production processes.
- ItemUnderstanding the uncertainty in global forest carbon turnover(Katlenburg-Lindau [u.a.] : Copernicus, 2020) Pugh, Thomas A.M.; Rademacher, Tim; Shafer, Sarah L.; Steinkamp, Jƶrg; Barichivich, Jonathan; Beckage, Brian; Haverd, Vanessa; Harper, Anna; Heinke, Jens; Nishina, Kazuya; Rammig, Anja; Sato, Hisashi; Arneth, Almut; Hantson, Stijn; Hickler, Thomas; Kautz, Markus; Quesada, Benjamin; Smith, Benjamin; Thonicke, KirstenThe length of time that carbon remains in forest biomass is one of the largest uncertainties in the global carbon cycle, with both recent historical baselines and future responses to environmental change poorly constrained by available observations. In the absence of large-scale observations, models used for global assessments tend to fall back on simplified assumptions of the turnover rates of biomass and soil carbon pools. In this study, the biomass carbon turnover times calculated by an ensemble of contemporary terrestrial biosphere models (TBMs) are analysed to assess their current capability to accurately estimate biomass carbon turnover times in forests and how these times are anticipated to change in the future. Modelled baseline 1985-2014 global average forest biomass turnover times vary from 12.2 to 23.5 years between TBMs. TBM differences in phenological processes, which control allocation to, and turnover rate of, leaves and fine roots, are as important as tree mortality with regard to explaining the variation in total turnover among TBMs. The different governing mechanisms exhibited by each TBM result in a wide range of plausible turnover time projections for the end of the century. Based on these simulations, it is not possible to draw robust conclusions regarding likely future changes in turnover time, and thus biomass change, for different regions. Both spatial and temporal uncertainty in turnover time are strongly linked to model assumptions concerning plant functional type distributions and their controls. Thirteen model-based hypotheses of controls on turnover time are identified, along with recommendations for pragmatic steps to test them using existing and novel observations. Efforts to resolve uncertainty in turnover time, and thus its impacts on the future evolution of biomass carbon stocks across the world's forests, will need to address both mortality and establishment components of forest demography, as well as allocation of carbon to woody versus non-woody biomass growth. Ā© 2020 SPIE. All rights reserved.
- ItemDraft Genome Sequence of a New Oscillospiraceae Bacterium Isolated from Anaerobic Digestion of Biomass(Washington, DC : American Society for Microbiology, 2020) Pascual, Javier; Hahnke, Sarah; Abendroth, Christian; Langer, Thomas; Ramm, Patrice; Klocke, Michael; Luschnig, Olaf; Porcar, ManuelHere, we present the genome sequence and annotation of the novel bacterial strain HV4-5-C5C, which may represent a new genus within the family Oscillospiraceae (order Eubacteriales). This strain is a potential keystone species in the hydrolysis of complex polymers during anaerobic digestion of biomass. Ā© 2020 Pascual et al.
- ItemUncertainty of biomass contributions from agriculture and forestry to renewable energy resources under climate change(Stuttgart : Gebrueder Borntraeger Verlagsbuchhandlung, 2015) Gutsch, M.; Lasch-Born, P.; LĆ¼ttger, A.B.; Suckow, F.; Murawski, A.; Pilz, T.
- ItemZielflƤchenorientierte, prƤzise Echtzeit-Fungizidapplikation in Getreide(Darmstadt : KTBL, 2015) Dammer, Karl-Heinz; Hamdorf, AndrĆ©; Ustyuzhanin, Anton; Schirrmann, Michael; Leithold, Peer; Leithold, Hermann; Volk, Thomas; Tackenberg, MariaIm Rahmen eines Verbundprojektes wurden Echtzeit-Applikationstechnologien mit berĆ¼hrungslosen Sensoren fĆ¼r prƤzise Fungizid-Spritzungen in Getreide entwickelt. Das Entscheidungshilfe- System proPlant expert.classic bzw. die Internetversion proPlant expert.com (proPlant GmbH) empfiehlt geeignete Fungizide und Dosierungen fĆ¼r ein bestimmtes Infektionsszenario der acht wichtigsten Blatt- und Ćhrenkrankheiten von Winterweizen. Das Precision- Farming-Modul āFungizidā, welches auf dem Terminal in der Traktorenkabine lƤuft, steuert das prƤzise Spritzverfahren. Das Modul bestimmt die lokale Zielapplikationsmenge wƤhrend des Spritzens durch Nutzung des lokalen Ultraschallsensorwerts als Eingabeparameter. In den Jahren 2013 und 2014 wurden Feldversuche in Winterweizen durchgefĆ¼hrt, um die Beziehung zwischen den Sensorwerten (Ultraschall- und Kamerasensor) und den Pflanzenparametern PflanzenoberflƤche (Leaf Area Index, LAI) sowie Biomasse zu analysieren. Diese sind fĆ¼r einen ƶrtlich angepassten variablen Fungizideinsatz zur Bemessung der Spritzmenge wichtig. Die Messungen wurden mehrmals wƤhrend der Vegetationsperiode an visuell ausgewƤhlten Stichprobenpunkten entsprechend der unterschiedlichen Bestandsdichte durchgefĆ¼hrt. Nach Ćnderungen an der Sensortechnik konnten fĆ¼r 2014 signifikante lineare Regressionsmodelle zur Beschreibung der Beziehung zwischen den Sensorwerten und den zwei Pflanzenparametern LAI sowie Biomasse gefunden werden.
- ItemSpatially explicit analysis identifies significant potential for bioenergy with carbon capture and storage in China([London] : Nature Publishing Group UK, 2021) Xing, Xiaofan; Wang, Rong; Bauer, Nico; Ciais, Philippe; Cao, Junji; Chen, Jianmin; Tang, Xu; Wang, Lin; Yang, Xin; Boucher, Olivier; Goll, Daniel; PeƱuelas, Josep; Janssens, Ivan A.; Balkanski, Yves; Clark, James; Ma, Jianmin; Pan, Bo; Zhang, Shicheng; Ye, Xingnan; Wang, Yutao; Li, Qing; Luo, Gang; Shen, Guofeng; Li, Wei; Yang, Yechen; Xu, SiqingAs China ramped-up coal power capacities rapidly while CO2 emissions need to decline, these capacities would turn into stranded assets. To deal with this risk, a promising option is to retrofit these capacities to co-fire with biomass and eventually upgrade to CCS operation (BECCS), but the feasibility is debated with respect to negative impacts on broader sustainability issues. Here we present a data-rich spatially explicit approach to estimate the marginal cost curve for decarbonizing the power sector in China with BECCS. We identify a potential of 222āGW of power capacities in 2836 counties generated by co-firing 0.9 Gt of biomass from the same county, with half being agricultural residues. Our spatially explicit method helps to reduce uncertainty in the economic costs and emissions of BECCS, identify the best opportunities for bioenergy and show the limitations by logistical challenges to achieve carbon neutrality in the power sector with large-scale BECCS in China.