Short-Term Effects of a Wildfire on the Endangered Dupont's Lark Chersophilus duponti in an Arid Shrub-Steppe of Central Spain

In Europe, Dupont’s Lark Chersophilus duponti is a threatened open-habitat bird. Prescribed burning has sometimes been proposed for its conservation, but without evidence of its effectiveness. To evaluate the short-term effects of a summer wildfire on this species, we performed several transect counts in the burnt and unburnt parts of a shrubsteppe in central Spain. The same transects were counted within a three-year interval prior to the fire and were repeated during the first two springs after the fire. We also measured the vegetation during the first two springs after the fire. In the burnt area, we observed a decrease of about 85–100% in Dupont’s Lark abundance, and about 7–15% in the control area. The disappearance of the scrub cover after fire and its slow regeneration, as well as the large increase in grass cover during the second year, may explain the decrease in this habitat-specialist bird species. Fire should be avoided in areas occupied by the Dupont’s Lark, as its negative effects in the short-term may cause local extinctions. However, prescribed burning may be used in neighboring areas to create new open habitats that may be subsequently colonized by this species.

Controlled Complete Suppression of Single-Atom Inelastic Spin and Orbital Cotunneling

The inelastic portion of the tunnel current through an individual magnetic atom grants unique access to read out and change the atom’s spin state, but it also provides a path for spontaneous relaxation and decoherence. Controlled closure of the inelastic channel would allow for the latter to be switched off at will, paving the way to coherent spin manipulation in single atoms. Here, we demonstrate complete closure of the inelastic channels for both spin and orbital transitions due to a controlled geometric modification of the atom’s environment, using scanning tunneling microscopy (STM). The observed suppression of the excitation signal, which occurs for Co atoms assembled into chains on a Cu2N substrate, indicates a structural transition affecting the dz2 orbital, effectively cutting off the STM tip from the spin-flip cotunneling path.