Posdoc, University College Dublin(UCD)
We are trying to find new mix design for artificial marine structures which is ecologically friendly
Research has shown that it is possible to promote biodiversity on artificial coastal structures through engineering design interventions, with potential for achieving associated socio-economic benefits – this is called ecological engineering (or eco-engineering). Although a wealth of ‘proof-of-concept’ evidence exists globally, eco-engineering designs have rarely been implemented in full-scale developments and many questions remain about their potential value and scope of application. A survey of stakeholder opinions in England and Wales indicated that a lack of awareness of and confidence in the evidence supporting these eco-engineering solutions is a key barrier to their implementation. In the last decades, the prevalence of artificial marine structures along natural shorelines has increased significantly. In some parts of the world, more than half of the available natural shoreline has been covered by these structures. Epibiotic diversity has been shown to decrease significantly on submerged artificial structures due to the reduced environmental heterogeneity of artificial environments. Natural rocky shores provide microhabitats through their rough surfaces, pits, rock pools and crevices. In contrast, modern building materials typically fail to provide many of these features. The ecological value of artificial coastal infrastructure could be increased through careful design of pre–fabricated ecological engineering units. Material selection is a crucial parameter in the design of these units. Reinforced concrete plays an important role in the design process due to its ease of production, relatively low cost and its suitability for mass construction. To maximise the potential of concrete to support biodiversity and natural capital, binder composition, aggregate type, and texture are considered to be important parameters. To investigate these parameters, an experimental programme has been developed which is focusing on a number of different concrete designs. Key engineering parameters, such as strength, chloride diffusion coefficient, and their ecological colonisation performance are evaluated.
Abstract: We present a preliminary predictive model of Oldowan stone artefact and scavenged larger mammal bone assemblages for 11 landscape facets modeled earlier to occur across a large portion (> 300 km2) of the paleo-Olduvai Basin during lowermost Bed II times. This second phase of model-building is based on our earlier characterizations of the basin's landscape ecostructure and the inter-facet distribution of key resources and hazards probably encountered by Late Pliocene hominids (Peters & Blumenschine, 1995, 1996). Our current extension of the model of hominid-landscape interactions specifies additional theoretical components, including: (1) the assumed capabilities of Oldowan hominids (presumably Homo habilis, primarily); (2) the landscape-facet-specific tasks they carried out; (3) the immediate stone and bone task residues they produced; and (4) the predicted composition, condition, density, and clustering of stone artefact and butchered and unbutchered bone assemblages for each facet. We develop ecological linkages between these new and formerly reported modeling components, the most fundamental of which is the facet-specific degree of tree/shrub cover abundance, and the correlated degree of competition among larger carnivores and hominids for scavengeable larger mammal carcasses. These factors condition variability among landscape facets in scavenging opportunities encountered by hominids, which in our model is the major predictor of bone and stone artefact assemblage composition. The predictive value of scavenging reflects the bias of paleoanthropological traces toward technology and butchery in their landscape context, but the model is surprisingly insensitive to what are usually thought to be critical social components of hominid land use. The predictions for the traces of hominid-landscape interactions modeled herein can be tested in the future against the landscape archaeological sample being excavated from lowermost Bed II by the Olduvai Landscape Paleoanthropology Project.
Pub.: 03 Jul '98, Pinned: 06 Jul '18