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Cecilia T. Satta Sílvia Anglès Esther Garcés Nicola Sechi Silvia Pulina Bachisio Mario Padedda Daniela Stacca Antonella Lugliè 《Estuaries and Coasts》2014,37(3):646-663
The present study identified and quantified dinoflagellate cysts in surface sediments from three Mediterranean lagoons. Sediment samples were recovered from 11 stations in May 2009 at Cabras Lagoon, eight stations in May 2010 at Corru S'Ittiri Lagoon, and five stations in May 2011 at Santa Giusta Lagoon. Fifty-three dinoflagellate cyst morphotypes were identified. Sixteen species are first reports for the lagoons, and two for the Mediterranean Sea. Moreover, a new Scrippsiella species was discovered in Cabras. Seven harmful algal species were identified, primarily belonging to the potentially toxic genus Alexandrium. Total cyst abundance, number of morphotypes, and assemblages varied among lagoons, and each lagoon showed a distinct morphotype composition. A degree of heterogeneity was also detected within lagoon. Cabras and Santa Giusta cyst assemblages were characterised by morphotypes belonging to the autotrophic genus Scrippsiella, whereas Corru S'Ittiri assemblages showed dominance of heterotrophic morphotypes, including Protoperidinium cf tricingulatum. Differentiation among lagoons was also evident according to environmental conditions. Salinity proved to be a fundamental variable in determining total cyst abundance, morphotype number, and composition. This study was among the first to examine dinoflagellate cyst composition in coastal lagoons, especially from the Mediterranean region, and contributed data that increased our knowledge of cyst-producing dinoflagellates in these environments. 相似文献
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Deniz Arca Hulya Keskin Citiroglu Hakan S. Kutoglu Cetin Mekik Tomonori Deguchi 《Natural Hazards》2017,87(1):307-322
Kozlu is a mining town only 5 km away from the main city of Zonguldak and initially was not favored for settlement due to its rugged and hilly topography. However, along with hard coal production in large quantities throughout the years came the industrialization at its full speed with plenty job opportunities which then gave rise to intense population in the region where there were only a few sheds and slums just a century ago. Workers migrating to Kozlu in thousands needed dwellings to live in, but the law, so-called the Coal Basin Restrictions Law which came in effect in 1910, hindered the implementation of zoning plans. Planned housing was not possible in the region not until the abolishment of the law in 1986. During these 76 years, the settlement in the area mostly by the mining and industry workers was carried out without proper zoning plans, usually on demand basis. Today because of this unplanned housing and harsh topography, the Kozlu settlement area (KSA) has a history of being attraction point for many natural and man-made disasters which can be summarized as are topography, geological and carstic structure, mining activities and mass movements. In this study, a settlement suitability map is produced for the study area using a geographic information system. The map produced is designated into four settlement suitability zones, namely suitable to settlement, slightly suitable to settlement, suitable to settlement with precautions and unsuitable to settlement. It clearly shows that 24.73% of the study area lies in suitable and slightly suitable to settlement areas while the bulky rest pertains to suitable to settlement with precautions and unsuitable to settlement. The latest studies show that the 37.5% of the buildings and houses in the KSA are situated on the lithologic units identified as hydrogeological permeable and semipermeable, 7.8% on carstic caverns and a hefty rate of 47.6% on the surfaces deformed by mining-induced subsidence. Therefore, it is needless to claim that the administrators of Kozlu should promptly develop a settlement plan for the welfare of the city. 相似文献
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Natural Hazards - Located in the Mediterranean basin, one of the world’s leading places in terms of forest fires, Turkey is one of the countries where forest fires are experienced very often... 相似文献
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Michele Salis Alan A. Ager Mark A. Finney Bachisio Arca Donatella Spano 《Natural Hazards》2014,71(3):1389-1418
We evaluated the spatiotemporal changes in wildfire regime and exposure in a fire-prone Mediterranean area (Sardinia, Italy) in relation to changes in ignition patterns, weather, suppression activities, and land uses. We also used wildfire simulations to identify fine-scale changes in wildfire exposure of important features on the island. Sardinia experienced a sharp reduction in fire number and area burned between the periods 1980–1994 and 1995–2009. Despite this decrease, losses and fatalities from wildfires continue. This suggests that localized areas and seasons of high wildfire risk persist on the island. Our analysis showed (1) a reduction in area burned (60,000–20,000 ha/year) and ignitions (3,700–2,600 fires/year), (2) an advance of 15 days for the fire season peak, (3) an increase in spring temperatures, and (4) an increase in fire exposure for WUI areas. Little change was noted for land use types and associated fuels. Most likely the reduction in fire activity may be due to a combination of social factors and suppression capabilities. On the other hand, simulation modeling suggested pockets of high wildfire exposure in specific places. The combined empirical analyses and simulation modeling provided a robust approach to understanding the spatiotemporal dynamics of wildfire risk on the island. 相似文献
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