Chemical footprints of anthropogenic nitrogen deposition on recent soil C : N ratios in Europe

Abstract. Long-term human interactions with the natural landscape have produced a plethora of trends and patterns of environmental disturbances across time and space. Nitrogen deposition, closely tracking energy and land use, is known to be among the main drivers of pollution, affecting both freshwater and terrestrial ecosystems. We present a statistical approach for investigating the historical and geographical distribution of nitrogen deposition and the impacts of accumulation on recent soil carbon-to-nitrogen ratios in Europe. After the second Industrial Revolution, large swaths of land emerged characterized by different atmospheric deposition patterns caused by industrial activities or intensive agriculture. Nitrogen deposition affects soil C : N ratios in a still recognizable way despite the abatement of oxidized and reduced nitrogen emissions during the last 2 decades. Given a seemingly disparate land-use history, we focused on ~ 10 000 unmanaged ecosystems, providing statistical evidence for a rapid response of nature to the chronic nitrogen supply through atmospheric deposition

Social tipping dynamics in the energy system

The fast growth in renewables has led to an economic tipping point for the adoption of renewables. However, we do not observe a corresponding reduction in fossil fuel demand. The tipping point has not led to a system-wide energy transition. This paper reviews how the cost tipping point in renewables can initiate other social tipping dynamics in the energy transition and it presents energy communities as a promising and fast-growing niche environment that can exploit and foster such tipping dynamics

Simulation of EPR and Time Resolved EPR lineshapes in partially ordered phases

Simulation of magnetic resonance spectra of probes in partially ordered glasses requires in principle a numerical integration on the full set of three Euler angles Ohm=(alpha beta gamma) from a laboratory fixed to a molecule fixed reference frame. It is shown that it is possible to manage efficiently this problem by using the algebraic properties of the Wigner matrix elements. This analysis is applied to time resolved EPR (TREPR) spectra of a series of bis-adducts of C-60 in the ordered glass of a nematic liquid crystal solvent. A paramagnetic triplet state is created by light excitation and TREPR spectra are obtained with the external magnetic field set parallel or perpendicular to the director n of the mesophase. The preferred orientation in the mesophase of the triplet state zero field tensor is determined