Stakeholder perspectives on barriers to landslide risk governance

European Union directives as well as national legislation are placing great emphasis on the inclusion of stakeholder perspectives in the governance of risks from natural hazards. This should help decision makers formulate better policies. However, to date, there is little information on stakeholders’ perspectives with respect to landslide risk governance. This paper addresses the gap by reporting on research in Nocera Inferiore, Italy. The research is based on a documentary analysis, 43 semi-structured interviews and a survey submitted to 373 residents. The political instability, the unfairness of national funding allocation across municipalities and the residents’ lack of knowledge about risk assessment and emergency planning are some of the main barriers to effective risk governance. Moreover, there are divergent, sometimes even opposite, stakeholders’ views on several issues, such as the relevance of illegal development in risky areas. The results highlight the importance of addressing these divergent views and including the plurality of voices as a prerequisite for inclusive risk governance. The research provided essential background information for a participatory process, which was designed to support decisions on landslide risk mitigation measures in Nocera Inferiore (Linnerooth-Bayer et al. this issue). The methodology will be of more general interest to researchers and policymakers intent upon including stakeholder perspectives in natural risk governance.

     

Mycobiota associated with the rhodophyte alien species Asparagopsis taxiformis (Delile) Trevisan de Saint‐Léon in the Mediterranean Sea

This study is the first to investigate and characterize the mycobiota associated with the alien species Asparagopsis taxiformis, a rhodophyte classified as one of the ‘100 worst invasive species’ in the Mediterranean Sea by the Hellenic Center for Marine Research, as it threatens biodiversity. Fungal endophyte and epiphyte communities were investigated on algal specimens from two sampling sites on the island of Linosa (Marine Protected Area Isole Pelagie, Italy). 87% of the 24 specimens that were analysed for epiphytes displayed a microfungal colonization. No endophytes were found. Only a small amount of microfungi was found to be associated with this alga. Only five fungal taxa were isolated; two of which are sporadically associated with the alga, while three, Eurotium rubrum, Cladosporium cladosporioides and Cladosporium pseudocladosporioides, seem to be related to A. taxiformis. This scarcity could be related to algal chemical composition.     

Thermal Regime of Rock and its Relation to Snow Cover in Steep Alpine Rock Walls: Gemsstock,Central Swiss Alps

Snow cover influences the thermal regime and stability of frozen rock walls. In this study, we investigate and model the impact of the spatially variable snow cover on the thermal regime of steep permafrost rock walls. This is necessary for a more detailed understanding of the thermal and mechanical processes causing changes in rock temperature and in the ice and water contents of frozen rock, which possibly lead to rock wall instability. To assess the temporal and spatial evolution and influence of the snow, detailed measurements have been carried out at two selected points in steep north‐ and south‐facing rock walls since 2012. In parallel, the one‐dimensional energy balance model SNOWPACK is used to simulate the effects of snow cover on the thermal regime of the rock walls. For this, a multi‐method approach with high temporal resolution is applied, combining meteorological, borehole rock temperature and terrain parameter measurements. To validate the results obtained for the ground thermal regime and the seasonally varying snowpack, the model output is compared with near‐surface rock temperature measurements and remote snow cover observations. No decrease of snow depth at slope angles up to 70° was observed in rough terrain due to micro‐topographic structures. Strong contrasts in rock temperatures between north‐ and south‐facing slopes are due to differences in solar radiation, slope angle and the timing and depth of the snow cover. SNOWPACK proved to be useful for modelling snow cover–rock interactions in smooth, homogenous rock slopes.     

Tether orientation control for lunar elevator

This study focuses on spatial motion of the lunar elevator which is studied in the framework of elliptical restricted three-body problem. Analysis of dynamics of a spacecraft anchored to the Moon by a tether is done assuming that the tether’s length can be changed according to a prescribed law. The goal is to find the control laws that allow one to compensate for the eccentricity of the orbits, i.e., to maintain the pendulum at a fixed angle with respect to the Earth–Moon direction. The results have shown that the fixed orientation of the tether can be kept for several configurations of the system; some of these configurations are found to be stable. The obtained results can be applied to study the properties and possible configurations of the lunar elevator, as well as applications for small planets and asteroids.     

Dating recent floodplain sediments in the Hawkesbury‐Nepean River system,eastern Australia using single‐grain quartz OSL

Two fluvial sediment cores taken from a floodplain of the Hawkesbury‐Nepean River system in the Sydney region, eastern Australia are dated using Optically Stimulated Luminescence (OSL) to provide a reliable chronology essential for the management and planning of water resources. Nine charcoal ¹⁴C (AMS) dates constrain these OSL ages. Quartz extracted from seven OSL samples from each of the cores was measured using both single‐grain and multi‐grain OSL techniques. Three of the single‐grain natural dose distributions appear to be well bleached, but the others appear to be incompletely bleached to various degrees. Three minimum‐age models (MAM, MAM_UL and IEU) are applied to the single‐grain dose distributions. We conclude that these models give consistent age estimates. For one of the cores it appears to be necessary to use a minimum‐age model to obtain accurate ages, but in the other core incomplete bleaching is probably less important than postdepositional mixing and mixing during sampling. As a result, the burial age is probably best estimated using the weighted average of the individual single‐grain dose estimates. The application of multi‐grain OSL techniques to these samples results in an average apparent age overestimation of ～200 years, which is significant for these samples, but negligible for sediments older than a few thousand years. The intention is that the chronology obtained in this study will be used in conjunction with a proxy flood record, derived from floodplain sediments, to gain an understanding of the long‐term variability in periods of high and low rainfall in eastern Australia.     

Meso-scale variability of coastal suprabenthic communities in the southern Tyrrhenian Sea (western Mediterranean)

Meso-scale spatial variability of coastal suprabenthic communities inhabiting muddy bottoms at 50–80 m depth in three gulfs of northern Sicily (Western Mediterranean) was here investigated. Although similar as concerns the hydrological and oceanographic conditions, the three areas, that encompass a large portion of the continental shelf (135 km), are characterized by different geo-morphological features. In addition, they are subjected to different trawl fishery pressures. The Gulf of Castellammare is a semi-enclosed bay, where the trawling activity has been banned since 1990. The Gulf of Termini Imerese and the Gulf of Sant’Agata are open areas, subjected to high trawl fishing intensity. In terms of density, gammarid amphipods showed differences among the three gulfs; in terms of biomass, cumaceans and amphipods were more abundant in the Gulf of Castellammare than in the other two areas. Multivariate analyses provided evidence for separation of suprabenthic assemblages between the Gulf of Castellammare and the other two gulfs. The Gulf of Castellammare seemed to host the most diversified and stable community according to α- and β-diversity indices. In the same way the low value of δ¹³C vs. δ¹⁵N correlation found in the gulf of Castellammare, which evidences the occurrence of several food sources, supports the idea of a higher stability in the semi-enclosed, trawl-ban area. In the other two areas δ¹³C vs. δ¹⁵N correlations were high, suggesting the existence of a pelagic source sustaining the suprabenthic communities. This is also confirmed by the lower δ¹³C concentrations found in suprabenthic species. Taking into account the homogeneous oceanographic conditions among gulfs, other factors, such as geo-morphology and trawling pressure should be involved in the observed differences among the three areas in terms of assemblage structure, diversity, and trophodynamics of suprabenthic communities.     

Shallow fault segmentation of the Alpine fault zone,New Zealand revealed from 2- and 3-D GPR surveying

Where they are preserved, landforms that have been truncated and offset by past fault movements provide potentially valuable quantitative data that can be used to estimate slip rates. At such locations, it is important to investigate the fault zone in sufficient detail to understand how displacements are accommodated on individual fault strands. At a site along a northern section of the Alpine fault zone on the South Island of New Zealand, surface mapping of a series of faulted river terraces and channels has revealed a complicated and poorly understood paleoearthquake history. We have acquired high-resolution 2- and 3-D ground-penetrating radar (GPR) data over a large area (~ 500 × 500 m) of the terraces to map along-strike changes in shallow (<20 m) fault zone morphology. By identifying distinct reflection patterns within the topographically migrated 3-D GPR volumes and extrapolating them to the longer and more widely spaced GPR profiles, we determined the subsurface extent of two main structural/depositional facies that were juxtaposed by three left-stepping en-echelon fault strands. Two regions of warped strata are interpreted to result from transpressive folding between the overlapping strands, where displacement is transferred from one fault to the next. We suggest that diffuse deformation between the overlapping fault tips results in anomalously low estimates for horizontal and vertical fault displacements of some geomorphic features.     

Last glacial ice‐rafted debris off southwestern Europe: the role of the British–Irish Ice Sheet

Ice‐rafted debris (IRD) seeded into the ocean from Northern Hemisphere ice sheets is found in ocean cores along the southwestern European margin through the last glacial period. It is known that the origin of this IRD, especially off Iberia, can vary between North America and western Europe during short‐lived episodes of greatly enhanced iceberg flux, known as Heinrich events, although in most Heinrich events the IRD has a North American source. During the longer times of much lower IRD fluxes between Heinrich events, use of an intermediate complexity climate model, coupled to an iceberg dynamic and thermodynamic model, shows that background levels of IRD most likely originate from western Europe, particularly the British–Irish Ice Sheet. Combining modelling with palaeoceanographic evidence supports reconstructions of a short‐lived, but substantial, Celtic and Irish Sea Ice Stream around 23 ka. Copyright © 2010 John Wiley & Sons, Ltd.