Backcountry Campsite Environmental Changes and Effective Monitoring Practices: A Case Study in Kenai Fjords National Park

This report examines existing backcountry campsites’ resource conditions over a five-year period in Kenai Fjords National Park (KEFJ), Alaska. Using campsite ecological monitoring techniques, 101 campsites were assessed for area size, vegetation cover loss, condition class assessments, as well as other indicator variable measurements. This research utilized parametric, non-parametric, robust linear regression, and principal component analysis statistical approaches to inform park managers of: Spatial and temporal patterns in changing campsite ecological variable conditions. Predicted annual variability of each ecological variable by campsite, beach, and bay. Opportunities for possible improvements in the efficiency of the current monitoring protocol by identifying: An optimal sampling frequency. Key ecological variables to sample. Areas of concern to focus sampling efforts. An optimal sampling frequency. Key ecological variables to sample. Areas of concern to focus sampling efforts. Patterns in changing campsites were difficult to discern until examined by park region (i.e., bay). Tree damage, mineral soil exposure, and root exposure were indicator variables sensitive to change while campsite area displayed changes in some locations. Future monitoring protocols should replace the rapid and complete assessments with a streamlined comprehensive protocol that reduces the number of indicator variables to include: rapid campsite area measurements, tree damage, vegetation cover loss, tent rock counts, trail counts, condition class ratings, and ghost tree damage. Campsite assessments should be conducted at a three to five-year sampling interval and revised if large significant changes occur or there is a significant change in the level of visitor use. As parks and protected areas continue to see increases in visitation and overnight use, the potential for recreational impacts increases without the appropriate management strategies. Our conclusions provide evidence to determine suitable management approaches and can be applied to future monitoring protocols to ease the burden of time intensive and expensive sampling

Nonlinear coupling of continuous variables at the single quantum level

We experimentally investigate nonlinear couplings between vibrational modes of strings of cold ions stored in linear ion traps. The nonlinearity is caused by the ions' Coulomb interaction and gives rise to a Kerr-type interaction Hamiltonian H = n_r*n_s, where n_r,n_s are phonon number operators of two interacting vibrational modes. We precisely measure the resulting oscillation frequency shift and observe a collapse and revival of the contrast in a Ramsey experiment. Implications for ion trap experiments aiming at high-fidelity quantum gate operations are discussed

EIT ground-state cooling of long ion strings

Electromagnetically-induced-transparency (EIT) cooling is a ground-state cooling technique for trapped particles. EIT offers a broader cooling range in frequency space compared to more established methods. In this work, we experimentally investigate EIT cooling in strings of trapped atomic ions. In strings of up to 18 ions, we demonstrate simultaneous ground state cooling of all radial modes in under 1 ms. This is a particularly important capability in view of emerging quantum simulation experiments with large numbers of trapped ions. Our analysis of the EIT cooling dynamics is based on a novel technique enabling single-shot measurements of phonon numbers, by rapid adiabatic passage on a vibrational sideband of a narrow transition