Data Assimilation for a Geological Process Model Using the Ensemble Kalman Filter

We consider the problem of conditioning a geological process-based computer simulation, which produces basin models by simulating transport and deposition of sediments, to data. Emphasising uncertainty quantification, we frame this as a Bayesian inverse problem, and propose to characterize the posterior probability distribution of the geological quantities of interest by using a variant of the ensemble Kalman filter, an estimation method which linearly and sequentially conditions realisations of the system state to data. A test case involving synthetic data is used to assess the performance of the proposed estimation method, and to compare it with similar approaches. We further apply the method to a more realistic test case, involving real well data from the Colville foreland basin, North Slope, Alaska.Comment: 34 pages, 10 figures, 4 table

Microplastics Accumulation in Recirculating Aquaculture Systems (RAS)

It has in recent years been a shift in the land-based aquaculture production from flow through systems (FTS) to recirculating aquaculture systems (RAS). With emerging use of RAS, it is necessary with knowledge regarding potential issues, whereas one potentially increasing problem is accumulation of microplastics (MP) in the RAS water. The objects of this study were to determine MPs concentration in RAS water, if the MPs originated from within the RAS, and provide a size distribution of the particles. RAS water were sampled in triplicates from three different RAS at three different locations in Norway. The water for each RAS were sampled effluent of the fish tank, effluent of the drum filter, and effluent of the biofilter as well as make-up water and sludge. Bio-media from the corresponding RAS were also sampled. Organic material in the water samples were digested prior to filtration, and filters were stained with Nile Red for quantification. There were found MPs in all the RAS water samples with mean concentration of 61 MP/L at Sunndalsøra RAS, 371 MP/L at the commercial site RAS and 41 MP/L at Kårvika RAS. There were higher concentrations in the RAS water than in the make-up water for all locations, indicating that the MPs originated from within the systems. Sludge samples were only possible to quantify from Kårvika RAS, while sampling were not performed at the commercials site and MPs concentration were too high to perform a count in Sunndalsøra RAS. The sludge samples support that the origin of MPs are within the system, as more MPs leave then enters the RAS. Nuclear magnetic resonance (NMR) spectroscopy analyses gave almost identical signals as their reference, which were the corresponding bio-media. The MPs also showed indistinguishable similarities with polyethylene (PE), which the bio-media were made off. There were found no significant trends regarding concentration at the different sampling sites. All RAS had similar size distribution of the MPs with approximately 75% of the particles being less than 100 μm. In conclusion, there were high concentrations of MPs in RAS which likely were due to shattering of the bio-media. Future research is necessary to determine an accumulation rate, but the high abundance of MPs proves the emerging issue regarding MPs. And although RAS has the potential to be the environmental winner within aquaculture, there still are opportunities for improvement

National Parks and Other Protected Areas: Some Reflections on the Past and Prescriptions for the Future

The World Conservation Strategy stresses the maintenance of essential ecological processes and life-support systems, preservation of genetic diversity, and sustainable use of species and ecosystems—in brief, the integration of conservation with development. The present paper traces shifts in conservation policy, which originnally saw national parks as islands isolated from their surrounding communities, through to the evolving concept of protected areas integrated with development programmes. It stresses the need for protected areas, and notes that only about 2% of the world's continental land-mass can be so classified. It is thereofre imperative for the survival of Nature and Man that a closer linkage be established between protection and development functions in such a way that both are seen as essential from a social and economic viewpoint. The continuing exploitive pressures on living natural resources are noted, and suggestions are made towards mitigating the impact of armed conflict and increasing financing for protected areas in order to achieve conservation and development objective

How can hospitality companies retain their hospitality talents?

The purpose of this thesis is to examine how hospitality companies can retain their hospitality talents. Using a qualitative case study approach to examine hospitality talents ́ criteria for intention of loyalty and to building a career in a particular hospitality company. Using semi- structured interviews, the study investigated 10 Norwegian hospitality students or frontline employees who intended for a career in the hospitality industry. Drawing on the framework of self-determination theory and social exchange theory, the study contributes with knowledge about how to retain hospitality talents by suggesting that the focus and process of retention strategies should reflect inherently motivating needs. Leaders should focus on designing intrinsic motivational job designs and facilitate good social relations. The study also suggests organisations to develop and nurture culture for career development and that leaders should support employees ́ need for development in a different manner than merely the traditional vertical career development focus

Ecological Principles for the Establishment and Management of National Parks and Equivalent Reserves

The central role of ecology in park planning and management is now so well recognized that the establishment of park programmes without ecological advice seems unthinkable. Yet attempts to link ecological principles and planning principles are still fraught with difficulty. Communications between interdisciplinary teams are complex. The Authors of this paper illustrate how the principles of ecology and the practices of park management are interconnected and interdependent. The need for resource inventories as a foundation of park management is explored and emphasized as essential, as is the need for constant monitoring to ensure that conservation goals are attained. Underlying the article are basic convictions that dynamic ecosystems require dynamic management, and that management in the future will be required increasingly to attain specific conservation objective