Visions for organic bioenergy production in Denmark

There is a large potential for organic bioenergy production, which can be combined with the present food production and the provision of multiple other goods and services required by society; i.e. a cleaner aquatic environment, or nature values in cultural landscapes. This paper presents six scenarios for bioenergy production from organic farming in Denmark, with a total energy production potential of around 6.7 PJ/yr. This potential is compared to the present energy use of around 2.5 PJ/yr, and the po-tentials for energy savings equalling 0.1-0.5 PJ/yr

Proteiner for fremtiden – græsproteiner. Det nationale bioøkonomispanels anbefalinger

Overblik over rapporten samt Det nationale bioøkonomispanels anbefalinge

Orbital Eccentricity -- Multiplicity Correlation for Planetary Systems and Comparison to the Solar System

The orbit eccentricities of the Solar System planets are unusually low compared to the average of known exoplanetary systems. A power law correlation has previously been found between the multiplicity of a planetary system and the orbital eccentricities of its components, for systems with multiplicities above two. In this study we investigate the correlation for an expanded data sample, by focusing on planetary systems as units (unlike previous studies that have focused on individual planets). Our full data sample contains 1171 exoplanets, in 895 systems, and the correlation between eccentricity and multiplicity is found to follow a clear power law for all multiplicities above one. We discuss the correlation for several individual subsamples, and find that all samples consistently follow the same basic trend regardless of e.g. planet types and detection methods. We find that the eccentricities of the Solar System fit the general trend and suggest that the Solar System might not show uncommonly low eccentricities (as often speculated) but rather uncommonly many planets compared to a "standard" planetary system. The only outlier from the power law correlation is, consistently in all the samples, the one-planet systems. It has previously been suggested that this may be due to additional unseen exoplanets in the observed one-planet systems. Based on this assumption and the power law correlation, we estimate that the probability of a system having 8 planets or more is of the order of 1%, in good agreement with recent predictions from analyses based on independent arguments.Comment: Accepted for publication in MNRAS; added acknowledgemen

Synergies between the expansion of biogas production and organic farming

Synergies between the expansion of biogas production and organic farming

Self-consistent atmosphere modeling with cloud formation for low-mass stars and exoplanets

ChH highlight financial support of the European Community under the FP7 by the ERC starting grant 257431.Context.  Low-mass stars and extrasolar planets have ultra-cool atmospheres where a rich chemistry occurs and clouds form. The increasing amount of spectroscopic observations for extrasolar planets requires self-consistent model atmosphere simulations to consistently include the formation processes that determine cloud formation and their feedback onto the atmosphere. Aims.  Our aim is to complement the Marcs model atmosphere suit with simulations applicable to low-mass stars and exoplanets in preparation of E-ELT, JWST, PLATO and other upcoming facilities. Methods.  The Marcs code calculates stellar atmosphere models, providing self-consistent solutions of the radiative transfer and the atmospheric structure and chemistry. We combine Marcs with a kinetic model that describes cloud formation in ultra-cool atmospheres (seed formation, growth/evaporation, gravitational settling, convective mixing, element depletion). Results. We present a small grid of self-consistently calculated atmosphere models for Teff = 2000-3000 K with solar initial abundances and log(g) = 4:5. Cloud formation in stellar and sub-stellar atmospheres appears for Teff < 2700 K and has a significant effect on the structure and the spectrum of the atmosphere for Teff < 2400 K. We have compared the synthetic spectra of our models with observed spectra and found that they fit the spectra of mid-To late-Type M-dwarfs and early-Type L-dwarfs well. The geometrical extension of the atmospheres (at τ = 1) changes with wavelength resulting in a flux variation of ∼ 10%. This translates into a change in geometrical extension of the atmosphere of about 50 km, which is the quantitative basis for exoplanetary transit spectroscopy.We also test Drift-Marcs for an example exoplanet and demonstrate that our simulations reproduce the Spitzer observations for WASP-19b rather well for Teff = 2600 K, log(g) = 3:2 and solar abundances. Our model points at an exoplanet with a deep cloud-free atmosphere with a substantial day-night energy transport and no temperature inversion.PostprintPeer reviewe

Effect of poplar trees on nitrogen and water balance in outdoor pig production – A case study in Denmark

Nitrate leaching from outdoor pig production is a long-standing environmental problem for surface and groundwater pollution. In this study, the effects of inclusion of poplar trees in paddocks for lactating sows on nitrogen (N) balances were studied for an organic pig farm in Denmark. Vegetation conditions, soil water and nitrate dynamics were measured in poplar and grass zones of paddocks belonging to main treatments: access to trees (AT), no access to trees (NAT) and a control without trees (NT), during the hydrological year April 2015 to April 2016. Soil water drainage for each zone, simulated by two simulation models (CoupModel and Daisy), was used to estimate nitrate leaching from the zones in each paddock. N balances (input minus output) for the treatments were computed and compared

Oplæg til afgrødekode der kan anvendes til græsarealer med vedagtig bevoksning til svin på friland

Formål med at etablere vedagtig bevoksning på græsarealer til frilandssvin: 1) Forbedre dyrevelfærden ved at give grisene adgang til et nærmiljø, der i højere grad afspejler grisens "naturlige" nærmiljø, og som giver grisene langt større mulighed for thermo-regulerende adfærd end på arealer udelukkende med græs. Græsfoderet vil kunne blive suppleret med frugt fra træerne og give beskæftigelse. Det vil derudover have en landskabsæstetisk betydning i forhold til at gøre hytterne mindre synlige i landskabet. Af hensyn til vinterperioden er det ønskeligt, at der også indgår stedsegrønne træer i beplantningerne. 2) Reducere kvælstofudvaskningen ved at etablere vedagtig bevoksning, der forventes at være mere bestandig end græs, der erfaringsmæssigt er meget vanskeligt at bevare på arealer med frilandssvin

Scenarios for use of biogas for heavy-duty vehicles in Denmark and related GHG emission impacts

Biogas may be a promising alternative fuel, mainly for heavy-duty vehicles, that can reduce CO2 emissions via substitution of fossil fuels and further reduce methane emissions from agricultural manure handling. However, as methane is a potent climate gas loss of methane from production to use of biogas is of concern. This study has analysed the potential biomass and biogas production from all Danish organic waste sources under different scenario assumptions for future scenario years. The analysis includes energy demand of the road transportation sector by means of transport and fuel types, and potential use of the limited biogas resource taking into account alternative fuel options available for transportation (electricity, hydrogen, biofuels). Further, the total differences in fuel consumption and GHG emissions due to the replacement of diesel-powered heavy-duty vehicles by gas-powered heavy-duty vehicles are estimated in a well-to-wheel perspective taking into account methane losses

Workshop - Ammonia losses in organic pig production

Methods for estimating ammonia losses from organic pig production in free range systems and in barns with outdoor pen