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Radiation use efficiency values estimation based on the biomass increment (one approach) and on NPP from eddy covariance (two approaches) estimation of NPP brings the values of 0.13, 0.40, and 0.47 g (C) MJ −1 , respectively. The productivity of terrestrial ecosystems is primarily reliant on the absorption of solar radiation energy and its conversion into biomass. Monteith (1977) first introduced the concept of radiation use efficiency (RUE), which expresses the effectiveness of a plant stand to use solar radiation for the formation of new biomass and to maintain existing biomass. The presented paper uses a long-term, decadal, time series of biomass data, which is based on forest inventory data and an allometric relation, and on the application of eddy covariance (EC) estimation of Net Primary Production (NPP). These approaches provide different values of light use efficiency (LUE). LUE is based on direct carbon exchange estimation, LUE i , which denotes instantaneous efficiency based on the relationship between the daily sum of incident global radiation (GR i ) and NPP and LUES, calculated as the ratio between the sum of NPP and the sum of GR i per growing season. RUE is based on direct yearly biomass increment expressed in carbon units (carbon = 0.5 × biomass) divided by the sum of GR i per year. The obtained values amount to 0.13, 0.40, and 0.47 g(C) MJ−1 for RUE, LUES, and LUE i , respectively. The higher value of LUE i reflects a direct relation with the efficiency of photosynthetic carbon pumping. In contrast, the RUE value, based on biomass inventories, is the result of woody mass formation that is caused by several mutually related physiological processes and “wastages” of radiation utilization.

Abstract This work describes the influence of biological concrete shielding model on neutron flux in reactor pressure vessel simulator placed in VVER-1000 transport benchmark. It includes an analysis and a comparison of experimental and calculated values of neutron flux. The thermal neutron fluxes in RPV simulator were measured when the reactor vessel or biological shielding was cladded in a cadmium foil absorbing thermal neutrons. The calculations have been performed using both CENDL 3.1 and ENDF/B VII nuclear data libraries.

We introduce a field survey method to assess the conservation condition of landscapes. Using a popular rapid assessment format, this study defines observable “stressed states” identified through the use of general metrics to gauge landscape degradation. Fifteen metrics within six thematic categories were selected through a literature review and extensive field trials. Field tests on the Greek island of Samothraki show a strong correlation between a single expert’s scores and five assessor’s scores at 35 landscape sites. Only three of the metrics did not maintain a high consistency among assessors; however, this is explained by the difficulty of interpreting certain anthropogenic stressors (such as livestock grazing) in Mediterranean semi-natural landscapes with culturally-modified vegetation patterns. The protocol and proposed index, with five conservation condition classes, identified areas of excellent and good quality, and reliably distinguished the most degraded landscape conditions on the island. Uncertainties and difficulties of the index are investigated, and further research and validation are proposed. The protocol effectively goes beyond a traditional visual aesthetic assessment; it can be used both by experts and non-scientists as a conservation-relevant multi-disciplinary procedure to support a holistic landscape diagnosis. The combination of an on-site experiential survey and its simple integrative format may be useful as a screening-level index, and for promoting local participation, landscape literacy and educational initiatives.

Heating and cooling using aquifer thermal energy storage (ATES) has hardly been applied outside the Netherlands, even though it could make a valuable contribution to the energy transition. The Climate-KIC project "Europe-wide Use of Energy from aquifers" - E-USE(aq) - aimed to pave the way for Europe-wide application of ATES, through the realization and monitoring of six ATES pilot plants across five different EU countries. In a preceding paper, based on preliminary results of E-USE(aq), conclusions were already drawn, demonstrating how the barriers for this form of shallow geothermal energy can be overcome, and sometimes even leveraged as opportunities. Based on final pilot project results, key economic and environmental outcomes are now presented. This paper starts with the analysis of specific technological barriers: unfamiliarity with the subsurface, presumed limited compatibility with existing energy provision systems (especially district heating), energy imbalances and groundwater contamination. The paper then shows how these barriers have been tackled, using improved site investigation and monitoring technologies to map heterogeneous subsoils. In this way ATES can cost-efficiently be included in smart grids and combined with other sources of renewable (especially solar) energy, while at the same time achieving groundwater remediation. A comparative assessment of economic and environmental impacts of the pilots is included, to demonstrate the sustainability of ATES system with different renewables and renewable-based technologies. The paper concludes with an assessment of the market application potential of ATES, including in areas with water scarcity, and a review of climate beneficial impact.

The objective of this paper is to present a new methodology for predicting the critical flashover voltage of polluted insulators based on fuzzy logic. The prediction contains not only the estimated value, but also the respective confidence interval based on the re-sampling method. Various parameters, such as the number and the base width of the triangular membership functions used for the fuzzification process, etc., are assigned different values in order to optimize the estimation of the critical flashover voltage. Additionally, different methods for training the fuzzy system are applied and compared for their appropriateness in accurately predicting the critical flashover voltage.

Overtourism is appearing more and more often in large world-famous cities and in many rural regions, where the infrastructure capacity is insufficient for large numbers of visitors. In rural communities, this creates resistance to tourism, traffic congestion, or damage to nature. Therefore, destinations experiencing tourism growth must have a strategy to prevent and limit the harmful effects of overtourism. The article presents a methodology that first identifies manifestations of overtourism in a destination and then uses a standardized procedure to evaluate the usability of different types of strategies in a selected destination. This procedure should lead to the creation of a comprehensive plan guaranteeing the sustainable development of tourism in the destination. The use of the methodology is explained at 12 rural locations in the Czech Republic, which were selected concerning the diversity of manifestations of overtourism.

Abstract In the present paper, linear hydroelastic analysis is performed for the assessment of the behavior of a Flexible Floating Breakwater (FFB), which represents not only a structure for shore protection but also a device for wave energy production with the utilization of a linear hydraulic Power Take-Off mechanism (PTO). The linear hydroelastic analysis is conducted in frequency domain with a radiation/diffraction 3D hydrodynamic model considering the effect of the flexibility of the FFB as well as the damping associated with the energy extraction by the PTO mechanism. A framework for this analysis is proposed and demonstrated, which includes three components: (a) a 3D structural model for an initial eigenvalue analysis, (b) a 3D hydrodynamic model for the hydroelastic analysis and (c) a numerical analysis for the calculation of the forces associated with the PTO and, also, for the estimation of the generated power. FFB consists of a grid of flexible floating modules connected flexibly in two directions by: (a) connectors with known properties and (b) hydraulic Power Take-Off mechanisms with known linear damping characteristics. The PTO mechanisms can be oriented in any possible direction in space. The investigation of the FFBs’ behavior is executed for two grids with different number of modules as well as for different combinations of translational and rotational stiffness of the FFB's connectors and different damping coefficients of PTO. The combined effect of wave energy extraction, behavior and a desired level of protection by the FFB is illustrated.

In the context of discussed global climate change the emphasis is placed mainly on the adaptability of the water management methodology at present time. Therefore a questionnaire inquiry oriented to the perception of the climate change impact and current state of adaptation strategies implementation was carried out and evaluated. The research was realised among the water management experts in six large transboundary basins: Elbe, Rhine, Guadiana, Amudaria, Orange and Nile. The questionnaire was divided into six parts concerning for example: expected climate change impacts, adaptation measures, drivers for development of adaptation strategy, adaptation barriers etc. Responses were evaluated with rating and the dominant answers and lists of priority were established. Results were evaluated looking for overall conclusions in all or almost all regions, as well as conclusions for each region. The main benefit of the research lies in the evaluation based principally on the opinions of policy makers, stakeholders and water managers in the river basins not on the climate scenarios. The outcomes have proved understanding of the climate change impact issue over all six basins, only the approach to adaptation is partly different. The historical development of water management in the basin influences the perception as well.