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Permanent plots for the study of natural regeneration after fire of Pinus halepensis Miller in dunal environment
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Study of some ecological factors acting in dunal environment after fire: solar radiation and thermal profiles of the soil
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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Istruzioni per l'esecuzione dei rilievi al suolo nei boschi di neoformazione
Get PDFA shift in the traditional land-use system of the Alps resulted in the widespread abandonment of agricultural lands and recovery of secondary woodlands.
Our study area, located in the Southern-Central Alps and extended for about 6000 km2, provided the opportunity to study this trend and suggest strategies for restoration ecology and sylviculture.
In order to estimate the secondary woodland area, we adopted a two-stages sampling design. In the first stage, 100 cells were randomly selected with replacement in a 4 km regularly spaced grid according to a probability depending on an auxiliary variable; in the second stage, 100 sample points were drawn randomly within each selected cell; the 10000 sampling points were then surveyed on 1973 and 1999 orthophotos to estimate the area of secondary woodlands.
These woodlands covered approximately 3% of the study area.
The 291 sample points located on naturally or artificially reforested abandoned land were surveyed further on the ground, recording ecological, biometrical, management and landscape attributes.
This report concerns the instructions for the field surveys
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