3 resultados para Conservation of forests and aquatic ecosystems
em Universidad de Alicante
Resumo:
Background. The extraction of salt from seawater by means of coastal solar salterns is a very well-described process. Moreover, the characterization of these environments from ecological, biochemical and microbiological perspectives has become a key focus for many research groups all over the world over the last 20 years. In countries such as Spain, there are several examples of coastal solar salterns (mainly on the Mediterranean coast) and inland solar salterns, from which sodium chloride is obtained for human consumption. However, studies focused on the characterization of inland solar salterns are scarce and both the archaeal diversity and the plant communities inhabiting these environments remain poorly described. Results. Two of the inland solar salterns (termed Redonda and Penalva), located in the Alto Vinalopó Valley (Alicante, Spain), were characterized regarding their geological and physico-chemical characteristics and their archaeal and botanical biodiversity. A preliminary eukaryotic diversity survey was also performed using saline water. The chemical characterization of the brine has revealed that the salted groundwater extracted to fill these inland solar salterns is thalassohaline. The plant communities living in this environment are dominated by Sarcocornia fruticosa (L.) A.J. Scott, Arthrocnemum macrostachyum (Moris) K. Koch, Suaeda vera Forsk. ex Gmelin (Amaranthaceae) and several species of Limonium (Mill) and Tamarix (L). Archaeal diversity was analyzed and compared by polymerase chain reaction (PCR)-based molecular phylogenetic techniques. Most of the sequences recovered from environmental DNA samples are affiliated with haloarchaeal genera such as Haloarcula, Halorubrum, Haloquadratum and Halobacterium, and with an unclassified member of the Halobacteriaceae. The eukaryote Dunaliella was also present in the samples. Conclusions. To our knowledge, this study constitutes the first analysis centered on inland solar salterns located in the southeastern region of Spain. The results obtained revealed that the salt deposits of this region have marine origins. Plant communities typical of salt marshes are present in this ecosystem and members of the Halobacteriaceae family can be easily detected in the microbial populations of these habitats. Possible origins of the haloarchaea detected in this study are discussed.
Resumo:
The process of seed dispersal of many animal-dispersed plants is frequently mediated by a small set of biotic agents. However, the contribution that each of these dispersers makes to the overall recruitment may differ largely, with important ecological and management implications for the population viability and dynamics of the species implied in these interactions. In this paper, we compared the relative contribution of two local guilds of scatter-hoarding animals with contrasting metabolic requirements and foraging behaviours (rodents and dung beetles) to the overall recruitment of two Quercus species co-occurring in the forests of southern Spain. For this purpose, we considered not only the quantity of dispersed seeds but also the quality of the seed dispersal process. The suitability for recruitment of the microhabitats where the seeds were deposited was evaluated in a multi-stage demographic approach. The highest rates of seed handling and predation occurred in those microhabitats located under shrubs, mostly due to the foraging activity of rodents. However, the probability of a seed being successfully cached was higher in microhabitats located beneath a tree canopy as a result of the feeding behaviour of beetles. Rodents and beetles showed remarkable differences in their effectiveness as local acorn dispersers. Quantitatively, rodents were much more important than beetles because they dispersed the vast majority of acorns. However, they were qualitatively less effective because they consumed a high proportion of them (over 95%), and seeds were mostly dispersed under shrubs, a less suitable microhabitat for short-term recruitment of the two oak species. Our findings demonstrate that certain species of dung beetles (such as Thorectes lusitanicus), despite being quantitatively less important than rodents, can act as effective local seed dispersers of Mediterranean oak species. Changes in the abundance of beetle populations could thus have profound implications for oak recruitment and community dynamics.
Resumo:
Cultural heritage sites all over the world are at risk due to aggressive urban expansion, development, wars and general obsolescence. Not all objects are recorded in detail although they may have social and historical significance. For example more emphasis is placed on the recording of castles and palaces than on crofters’ cottages or tenement blocks, although their history can be just as rich. This paper will investigate the historic fabric of Aberdeen through the use of digital scanning, supported by a range of media including old photographs and paintings. Dissemination of social heritage through visualisations will be explored and how this can aid the understanding of space within the city or specific area. Focus will be given to the major statues/monuments within the context of the city centre, exploring their importance in their environment. In addition studying why many have been re-located away from their original site, the reasons why, and how we have perhaps lost some of the social and historical importance of why that monument was first located there. It will be argued that Digital Media could be utilised for much more than re-creation and re-presentation of physical entities. Digital scanning, in association with visualisation tools, is used to capture the essence of both the cultural heritage and the society that created or used the sites in association with visualisation tools and in some way re-enacting the original importance placed upon the monument in its original location, through adoption of BIM Heritage.