RESUMO
The coastlines of many Arabian cities are now dominated by structures such as seawalls, breakwaters and jetties as urbanization has expanded rapidly in the region. Coastal development has substantially degraded the mangrove forests, saltmarshes, seagrass meadows, oyster beds and coral reefs that traditionally provided invaluable ecosystem goods and services to coastal trading villages of the Arabian Gulf. Regional awareness of environmental issues is growing, however, and local governments are increasingly promoting more sustainable urban development. The use of ecological engineering approaches, along with improved environmental policies, may mitigate some past impacts, and will potentially create new development projects with greater ecological benefits for more sustainable growth in the future. In this paper, we discuss past coastal development in the Gulf, and offer advice on how ecological engineering could be used to enhance the ecological benefits of coastal infrastructure, particularly by encouraging the colonization of juvenile corals and fishes. Such approaches can encourage more sustainable development of this increasingly urbanized seascape.
Assuntos
Conservação dos Recursos Naturais/métodos , Recifes de Corais , Desenvolvimento Sustentável , Animais , Antozoários , Cidades , Ecossistema , Política Ambiental , Peixes , Oceano Índico , Campos de Petróleo e Gás , Ostreidae , UrbanizaçãoRESUMO
The clownfish-sea anemone symbiosis has been a model system for understanding fundamental evolutionary and ecological processes. However, our evolutionary understanding of this symbiosis comes entirely from studies of clownfishes. A holistic understanding of a model mutualism requires systematic, biogeographic, and phylogenetic insight into both partners. Here, we conduct the largest phylogenetic analysis of sea anemones (Order Actiniaria) to date, with a focus on expanding the biogeographic and taxonomic sampling of the 10 nominal clownfish-hosting species. Using a combination of mtDNA and nuDNA loci we test (1) the monophyly of each clownfish-hosting family and genus, (2) the current anemone taxonomy that suggests symbioses with clownfishes evolved multiple times within Actiniaria, and (3) whether, like the clownfishes, there is evidence that host anemones have a Coral Triangle biogeographic origin. Our phylogenetic reconstruction demonstrates widespread poly- and para-phyly at the family and genus level, particularly within the family Stichodactylidae and genus Stichodactyla, and suggests that symbioses with clownfishes evolved minimally three times within sea anemones. We further recover evidence for a Tethyan biogeographic origin for some clades. Our data provide the first evidence that clownfish and some sea anemone hosts have different biogeographic origins, and that there may be cryptic species of host anemones. Finally, our findings reflect the need for a major taxonomic revision of the clownfish-hosting sea anemones.
Assuntos
Filogenia , Anêmonas-do-Mar/classificação , Anêmonas-do-Mar/genética , Simbiose/fisiologia , Animais , Antozoários/fisiologia , Evolução Biológica , DNA Mitocondrial/genética , Modelos BiológicosRESUMO
Worldwide, ISO 14001 certification for organizations has become the norm, but the Arab world accounts for an insignificant portion of all the certified organizations. There is a dearth of research on environmental management systems (EMS) in Arab and emerging countries and in public organizations. The objectives of this research are to: (1) examine the key drivers and challenges related to implementation of ISO 14001 certified EMS in the United Arab Emirates, an emerging Arab country and (2) compare and contrast these drivers and challenges between private and public organizations. We adopt an explorative, qualitative methodology, using semi-structured interviews with environmental managers in 11 organizations (6 private and 5 public) from different industrial sectors. Drivers of EMS certification were mostly similar between private and public organizations, with some differences. Compliance with regulations and standards, and increasing environmental performance were the main drivers for ISO 14001 certification in both private and public organizations. Commitment to sustainability was more important for public organizations. Cost reduction, competitors, leadership commitment and customers' demands were shared drivers, but more stressed by private organizations. Local community and employees' pressures were reported by private organizations only. The challenges to ISO 14001 implementation were similar for private and public organizations. They were: a lack of qualified human resources, practical challenges associated with implementation, a lack of regulations, a lack of support from management, and high costs. Our findings have implications for managers, academics, consultants, and policy makers in the UAE and other emerging markets.
Assuntos
Indústrias , Certificação , Consultores , Humanos , Liderança , Oriente MédioRESUMO
OBJECTIVE: In this study, we compared how users locate physical and equivalent three-dimensional images of virtual objects in a cave automatic virtual environment (CAVE) using the hand to examine how human performance (accuracy, time, and approach) is affected by object size, location, and distance. BACKGROUND: Virtual reality (VR) offers the promise to flexibly simulate arbitrary environments for studying human performance. Previously, VR researchers primarily considered differences between virtual and physical distance estimation rather than reaching for close-up objects. METHOD: Fourteen participants completed manual targeting tasks that involved reaching for corners on equivalent physical and virtual boxes of three different sizes. Predicted errors were calculated from a geometric model based on user interpupillary distance, eye location, distance from the eyes to the projector screen, and object. RESULTS: Users were 1.64 times less accurate (p < .001) and spent 1.49 times more time (p = .01) targeting virtual versus physical box corners using the hands. Predicted virtual targeting errors were on average 1.53 times (p < .05) greater than the observed errors for farther virtual targets but not significantly different for close-up virtual targets. CONCLUSION: Target size, location, and distance, in addition to binocular disparity, affected virtual object targeting inaccuracy. Observed virtual box inaccuracy was less than predicted for farther locations, suggesting possible influence of cues other than binocular vision. APPLICATION: Human physical interaction with objects in VR for simulation, training, and prototyping involving reaching and manually handling virtual objects in a CAVE are more accurate than predicted when locating farther objects.
Assuntos
Percepção de Forma/fisiologia , Desempenho Psicomotor/fisiologia , Tato/fisiologia , Interface Usuário-Computador , Adulto , Simulação por Computador , Feminino , Humanos , Masculino , Estimulação Física , Visão Binocular/fisiologia , Adulto JovemRESUMO
Expert opinion was assessed to identify current knowledge gaps in determining future changes in Arabian/Persian Gulf (thereafter 'Gulf') coral reefs. Thirty-one participants submitted 71 research questions that were peer-assessed in terms of scientific importance (i.e., filled a knowledge gap and was a research priority) and efficiency in resource use (i.e., was highly feasible and ecologically broad). Ten research questions, in six major research areas, were highly important for both understanding Gulf coral reef ecosystems and also an efficient use of limited research resources. These questions mirrored global evaluations of the importance of understanding and evaluating biodiversity, determining the potential impacts of climate change, the role of anthropogenic impacts in structuring coral reef communities, and economically evaluating coral reef communities. These questions provide guidance for future research on coral reef ecosystems within the Gulf, and enhance the potential for assessment and management of future changes in this globally significant region.
Assuntos
Conservação dos Recursos Naturais , Recifes de Corais , Pesquisa , Animais , Antozoários/crescimento & desenvolvimento , Biodiversidade , Mudança Climática , Previsões , Oceano ÍndicoRESUMO
Virtual Reality environments have the ability to present users with rich visual representations of simulated environments. However, means to interact with these types of illusions are generally unnatural in the sense that they do not match the methods humans use to grasp and move objects in the physical world. We demonstrate a system that enables users to interact with virtual objects with natural body movements by combining visual information, kinesthetics and biofeedback from electromyograms (EMG). Our method allows virtual objects to be grasped, moved and dropped through muscle exertion classification based on physical world masses. We show that users can consistently reproduce these calibrated exertions, allowing them to interface with objects in a novel way.