Colombiaʼs agriculture, forestry and other land use sector accounts for nearly half of its total greenhouse gas (GHG) emissions. The importance of smallholder deforestation is comparatively high in relation to its regional counterparts, and livestock agriculture represents the largest driver of primary forest depletion. Silvopastoral systems (SPSs) are presented as agroecological solutions that synergistically enhance livestock productivity, improve local farmers' livelihoods and hold the potential to reduce pressure on forest conversion. The department of Caquetá represents Colombia's most important deforestation hotspot. Targeting smallholder livestock farms through survey data, in this work we investigate the GHG mitigation potential of implementing SPSs for smallholder farms in this region. Specifically, we assess whether the carbon sequestration taking place in the soil and biomass of SPSs is sufficient to offset the per-hectare increase in livestock GHG emissions resulting from higher stocking rates. To address these questions we use data on livestock population characteristics and historic land cover changes reported from a survey covering 158 farms and model the carbon sequestration occurring in three different scenarios of progressively-increased SPS complexity using the CO 2 fix model. We find that, even with moderate tree planting densities, the implementation of SPSs can reduce GHG emissions by 2.6 Mg CO 2e ha −1 yr −1 in relation to current practices, while increasing agriculture productivity and contributing to the restoration of severely degraded landscapes.

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Optical integrated quantum computing protocols, in particular using the dual-rail encoding, require that waveguides cross each other to realize, e.g., SWAP or Toffoli gate operations. We demonstrate efficient adiabatic crossings. The working principle is explained using simulations, and several test circuits are fabricated in silicon nitride (SiN) to characterize the coupling performance and insertion loss. Well-working crossings are found by experimentally varying the coupler parameters. The adiabatic waveguide crossing (WgX) outperforms a normal directional coupler in terms of spectral working range and fabrication variance stability. The insertion loss is determined using two different methods: using the transmission and by incorporating crossings in microring resonators. We show that the latter method is very efficient for low-loss photonic components. The lowest insertion loss is 0.18 dB (4.06%) enabling high-fidelity NOT operations. The presented WgX represents a high-fidelity (96.2%) quantum NOT operation.

Die Darstellung des Hochgebirges in der Malerei nahm ihren Anfang im späten 17. Jahrhundert. Unter den frühen Pionieren ragt Felix Meyer von Winterthur hervor, dessen Gletscheransichten im Zusammenhang mit den naturwissenschaftlichen Forschungen vor allem Johann Jakob Scheuchzers zu sehen sind. Einen Höhepunkt bilden die über 150 Alpendarstellungen, die der Aargauer Caspar Wolf im Auftrag des Berner Verlegers Abraham Wagner zwischen 1774 und 1778 ausführte. In ihnen manifestiert sich ein grosses Interesse nicht nur für die Topographie der Alpen, sondern auch für deren geologischen Aufbau und für die Wirkungsmechanismen in der Natur. Wolfs Gemälde sind schönster bildlicher Ausdruck der seit der Mitte des 18. Jahrhunderts aufkommenden Alpenbegeisterung, die wesentlich auf den Schriften von Haller und Rousseau beruhte und die zu einem rapiden Aufschwung des Tourismus in der Schweiz führte.