7 research outputs found
Exploiting historical rainfall and landslide data in a spatial database for the derivation of critical rainfall thresholds
Critical rainfall thresholds for landslides are
powerful tools for preventing landslide hazard. The
thresholds are commonly estimated empirically starting
from rainfall events that triggered landslides in the past.
The creation of the appropriate rainfall\u2013landslide database
is one of the main efforts in this approach. In fact, an
accurate agreement between the landslide and rainfall
information, in terms of location and timing, is essential in
order to correctly estimate the rainfall\u2013landslide relationships.
A further issue is taking into account the average
moisture conditions prior the triggering event, which reasonably
may be crucial in determining the sufficient
amount of precipitation. In this context, the aim of this
paper is exploiting historical landslide and rainfall data in a
spatial database for the derivation of critical rainfall
thresholds for landslide occurrence in Sicily, southern
Italy. The hourly rainfall events that caused landslides
occurred in the twentieth century were specifically identified
and reconstructed. A procedure was proposed to
automatically convert rain guages charts recorded on paper
tape into digital format and then to provide the cumulative
rainfall hyetograph in digital format. This procedure is
based on a segmentation followed by signal recognition
techniques which allow to digitalize and to recognize the
hyetograph automatically. The role of rainfall prior to the
landslide events was taken into account by including in the analysis the rainfall occurred 5, 15 and 30 days before each
landslide. Finally, cumulated rainfall duration thresholds
for different exceedance probability levels were determined.
The obtained thresholds resulted in agreement with
the regional curves proposed by other authors for the same
area; antecedent rainfall turned out to be particularly
important in triggering landslides
Data from: Conservation priorities of Iberoamerican pig breeds and their ancestors based on microsatellite information
Criollo pig breeds are descendants from pigs brought to the American continent starting with Columbus second trip in 1493. Pigs currently play a key role in social economy and community cultural identity in Latin America. The aim of this study was to establish conservation priorities among a comprehensive group of Criollo pig breeds based on a set of 24 microsatellite markers and using different criteria. Spain and Portugal pig breeds, wild boar populations of different European geographic origins and commercial pig breeds were included in the analysis as potential genetic influences in the development of Criollo pig breeds. Different methods, differing in the weight given to within- and between-breed genetic variability, were used in order to estimate the contribution of each breed to global genetic diversity. As expected, the partial contribution to total heterozygosity gave high priority to Criollo pig breeds, whereas Weitzman procedures prioritized Iberian Peninsula breeds. With the combined within- and between-breed approaches, different conservation priorities were achieved. The Core Set methodologies highly prioritized Criollo pig breeds (Cr. Boliviano, Cr. Pacifico, Cr. Cubano and Cr. Guadalupe). However, weighing the between- and within-breed components with FST and 1-FST, respectively, resulted in higher contributions of Iberian breeds. In spite of the different conservation priorities according to the methodology used, other factors in addition to genetic information also need to be considered in conservation programmes, such as the economic, cultural or historical value of the breeds involved