Search results for "Geographic Distribution"
showing 10 items of 37 documents
The genusThymus(Lamiaceae) in Sicily
2015
An update on the taxonomy and geographic distribution of the genus Thymus in Sicily is given. This study is based on literature, herbarium and field investigations. In total, five taxa belonging to Thymus sect. Serpyllum (Th. richardii subsp. nitidus, Th. longicaulis and Th. praecox subsp. parvulus) and Th. sect. Hyphodromi (Th. spinulosus and Th. paronychioides) occur in Sicily. For each one, information about taxonomy, habitat, phenology, chromosome number and distribution are provided. Furthermore, the name Thymus pedicillatus Lojac. is here typified. Finally, an analytical key for the identification of the studied taxa is proposed.
Social Network Analysis and Qualitative Interviews for Assessing Geographic Characteristics of Tourism Business Networks.
2015
This study integrates quantitative social network analysis (SNA) and qualitative interviews for understanding tourism business links in isolated communities through analysing spatial characteristics. Two case studies are used, the Surselva-Gotthard region in the Swiss Alps and Longyearbyen in the Arctic archipelago of Svalbard, to test the spatial characteristics of physical proximity, isolation, and smallness for understanding tourism business links. In the larger Surselva-Gotthard region, we found a strong relationship between geographic separation of the three communities on compartmentalization of the collaboration network. A small set of businesses played a central role in steering col…
Geovisualizing the sail-to-steam transition through vessel movement data
2017
International audience; Technological transitions in the maritime and port industries go along with increased transport and economic efficiency, resulting in faster movements and longer travelled distances. Yet, such transformations may also enhance disparities between winners and loosers, should they be ports or shipping companies. This research focuses on the particular case of the transition from sail to steam over the period 1890-1925, which witnesses the rapid replacement of sailing vessels, the latter concentrating 65% of the world fleet in 1890 but only 3.5% in 1925. It applies a variety of measures to compare how these two layers overlap in the network (at links and ports) and what …
Geodiversity and geoheritage: Detecting scientific and geographic biases and gaps through a bibliometric study
2019
Abstract Many scientists have recognized that there is diversity in nature, including biodiversity, geodiversity, and pedodiversity. Studies in biodiversity date back as far as the 1700s, but geodiversity and pedodiversity studies are much more recent, dating to the late 1970s to early 1980s. Given that we are now approaching 40 years of geodiversity and geoheritage work, this study was undertaken to determine areas that have been well addressed and where current gaps are. This was accomplished by reviewing the publications in the journal “Geoheritage”, the Scopus and Google Scholar databases, and established geoparks according to UNESCO records. It was found that geodiversity studies typic…
Eupelmus spermophilus Silvestri (Hymenoptera: Chalcidoidea), an Indigenous Olive Seed Wasp Potentially Harmful to Olive Growing in the Western Cape, …
2021
The objectives of this study were the specific taxonomic confirmation of the main olive seed wasp (OSW) attacking commercial olives in the Western Cape, to investigate monitoring methods and seasonal occurrence of OSW, to determine the potential economic damage of infestations, and to ascertain the geographic distribution of OSW in the regions where olives are cultivated in the Western Cape. Morphological and molecular methods were used to identify all the species obtained from cultivated olives at two trial sites near Stellenbosch and Agter-Paarl. Eupelmus spermophilus Silvestri (Hymenoptera: Chalcidoidea) was by far the most frequent and widespread olive seed wasp. Monitoring with yellow …
Ammonite extinction and nautilid survival at the end of the Cretaceous
2014
One of the puzzles about the end-Cretaceous extinctions is why some organisms disappeared and others survived. A notable example is the differential extinction of ammonites and survival of nautilids, the two groups of co-occurring, externally shelled cephalopods at the end of the Cretaceous. To investigate the role of geographic distribution in explaining this outcome, we compiled a database of all the occurrences of ammonites and the nautilid genus Eutrephoceras in the last 0.5 m.y. of the Maastrichtian. We also included recently published data on ammonite genera that appear to have briefly survived into the Paleocene. Using two metrics to evaluate the geographic range of each genus (first…
Two new antarctic species of the genus Schizotricha Allman, 1883 (Cnidaria, Hydrozoa)
1998
Two new antarctic species of the genus Schizotricha Allman have been studied. The material comes from the Scotia Sea (Antarctica) and was collected by the Spanish antarctic expedition `Antartida 8611'. Both species are described and figured and the systematic position is discussed. A general survey of the geographical and bathymetrical distribution of the antarctic and subantarctic species of the genus is given. Finally, a key for the identification of the antarctic and subantarctic species of the genus, together with a comparative table including main features, are presented.
On two new species of Oswaldella Stechow, 1919 (Cnidaria, Hydrozoa) from Bransfield Strait (Antarctica)
1998
Two species of the genus Oswaldella Stechow, 1919 new to science (Oswaldella crassa sp. nov. and O.␣curiosa sp. nov.) were studied. Both species are described and figured; their systematic position amongst the remaining species of the genus is discussed. The material originates from the Bransfield Strait area (Antarctica) and was collected during the United States Antarctic Research Program with R.V. Eltanin. A comparative table listing the main features of the known species of Oswaldella is presented. Finally, a general survey of geographical and bathymetrical distribution of the known species of Oswaldella is given.
Is Spain a lumpy country? A dynamic analysis of the ‘lens condition’
2008
We implement the ‘lens condition’ of Deardoff (1994) to investigate whether lumpiness, an excessively uneven geographic distribution of production factors, is large enough to allow for regional specialization of production at different factor prices. Using data from 50 Spanish provinces over the period 1964 to 2001, we show that Spain evolved from being a lumpy economy to a state where lumpiness no longer mattered.
Biogeographic patterns of belemnite body size responses to episodes of environmental crisis
2019
Body size changes have been investigated through episodes of environmental crisis among several groups of organisms but the relative contribution of within-lineage size changes, selective extinction and origination of taxa on these patterns is still being debated. Rapid warming, anoxia, and perturbations of the carbon cycle linked with volcanic activity, as well as their impact on marine diversity are well documented for the Pliensbachian-Toarcian (Pli-Toa) boundary and for the Toarcian Oceanic Anoxic Event (T-OAE). Belemnites were a very abundant and successful cephalopod group in the Mesozoic oceans playing a paramount role in the oceanic trophic webs. Belemnites have mainly been studied …