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Volume XVII |

Considerations on the Influence of Micro Urban Heat Islands to the Temperature – Humidity Index During July 2017 in Craiova City Centre

Abstract: According to the National Administration of Meteorology, July 2017 was the hottest July months in the last decade, with one of the longest period with canicular temperatures in the last decades, too. In many regions of Romania, including Oltenia and Craiova city, too, yellow or orange code warning had to be announced. To determine real thermal discomfort sensation felt by the population of Craiova city, experimental research concerning micrometeorological measurements of the real temperature and relative humidity that contribute to the local Temperature – Humidity Index (THI) value was performed. According to the experimental research results, confirmed by using thermovision too, in Craiova city centre, five micro urban heat islands (MUHI) were identified. For three streets and a public square, despite the small mean value of relative humidity, due to the temperature’s high mean value, in these hot spots the THI mean average was 89.97, and for this thermal discomfort sensation, special protection measures would be needed. The same air micrometeorological parameters in these four hot spots were compared with the ones recorded in English Park, where due to vegetation and trees’ shadow, the THI average was 84.11, thus the real thermal discomfort sensation would have made necessary adequate protection measures. In order to study the intensity and spatial pattern of the MUHI, thermal infrared remote sensing (thermovision) was used to observe the surface of MUHI as a complementary indicator of the thermal discomfort sensation with in MUHI. The paper presents relevant interdependence relationships between the near surface air temperatures and pavement/ buildings surface temperatures that have been found for MUHI in Craiova’s city centre. The paper proposes practical methods that could be used to decrease the pavements’ and buildings’ walls temperatures, thus contributing to the decrease of THI in the MUHI within Craiova city centre.

Volume XVII |

The analysis of relationship between microclimate and microbial carbon-dioxide production in the soils of the Tapolca and Gömör-Tornai karst terrains, Hungary

Abstract: In the karst areas, the epikarst system is a very sensitive environment, due to its position at the interface between soil and vadose zone. The epikarst is a weathered zone that develops as a result of both abiotic and biotic processes. In this paper we present the result of the complex investigations of epikarst zone which overlap dolines within two typical karst areas (Gömör-Torna and Tapolca) from Hungary, based on multicriteria analysis techniques (microbiological activity assessed as biomass amount and CO2 production, seasonality of air and soil microclimate, slope orientation and exposition), in order to reveal control factors of karst processes, the territorial and local distinctions of karst dissolution that occur in the epikarst zone. The data were compared, taking into account the human activities’ impact on both sampled study areas. After four years of monitoring, the results show that there are significant seasonal and diurnal variations of physical, chemical and biotic parameters of soil that cover and affect the epikarst zone. Spatial variations of these parameters were recorded as well.

Volume XVII |

Arch dam failure preliminary analysis using HEC-RAS and HEC-GEO RAS modeling. Case study Someșul Rece 1 reservoir

Abstract: This paper presents a preliminary analysis/simulation of the Someşul Rece 1 dam breaking scenario, from the homonym hydrographic basin, located in the north-eastern part of the Apuseni Mountains, at a 0.1 % probability tributary flow rate calculation. The study of the floodplain areas, that occur after the failure of the Someşul Rece 1 dam, was achieved with the help of 1D hydrological modelling. This type of modelling is one of the most complex (Cameron et al., 2006), involving both, the definition of a model with temporal evolution of the dam rupture, and the simulation of a unsteady flow stream in the downstream sector. For the dam analysed area and the downstream sector, several scenarios and modelling of hydrological systems was achieved, with the help of HEC-RAS 5.0.3 software, developed by the Hydrologic Engineering Center (U.S. Army Corps of Engineers).
This free software is the most widely used worldwide in the domain, particularly by the official agencies, having a continuous development, given by the involvement of specialists. The software simplifies the problem of hydrodynamic modelling, due to the limitation to a 1D model. Because the flood obviously has a spatial character, GIS software (ESRI ArcGis with the HEC-GeoRAS extension) were used in determining and defining the hydrographic elements (channel, talweg, banks etc.) and, also, in the representation of the results. Maps of the flood-prone areas have been developed, maps which indicated the magnitude of the estimated accidental flood downstream. The results of the simulation were also used to determine the anticipation time.

Volume XVII |

Playing with water – An introduction to experimental hydrology

Abstract: Water is the most important resource for the humankind, thus understanding hydrological processes could be con-sidered a vital task. Therefore, the main aims of this papers are to assess: (i) the current status of hydrologic field ex-periments; (ii) the techniques and the stages of the field hydrologic experiments at the microscale/plot-scale. Microscale hydrological studies are important both socially and economically as they emphasize the role of key factors (e.g. slope) in the utilization of water resources, the identification of critical hydrological thresholds for mobilizing, the propagation of soil particles in water flows and also the time it takes for pesticides, nutrients, and heavy metals to be mobilized. The key to conducting a successful hydrological microscale experiment lies in performing repeated attempts in the field. From an economic point of view, expedition (temporary) hydrologic field experiments are beneficial, as they shorten the working period and reduce the financial costs of the data acquisition process.
One of the challenges of experimental hydrology is the manipulation of “upscaling” or the statistical approach taken towards gathering and processing data.

Volume XVII |

Estimation of drinking water supply and its future trends in Varanasi city, India

Abstract: The current study shows the estimation of drinking water supply, future trends and related issues in Varanasi City, India. Varanasi (from 25013’N to 25024’N latitudes and from 820 54’E to 830 04’E longitude) is one of the most important and historic city located almost in the Middle Ganga valley in the northern plain of India. For the convenience of civic administration, the city is presently divided into 90 wards and for the purpose of extending adequate and safe water supply facilities to the entire area, the city has been divided presently into 16 water supply zones of which 5 zones lie in the trans-Varuna area and the remaining 11 zones in the cis-Varuna area. The present work is based on the secondary sources of data which are obtained from Water Supply Department (Jal Sansthan), Nagar Nigam (Municipal Corporation) of Varanasi. In the first phase of the study, data pertaining to ward wise generation of water supply is collected from Water Supply Department, NNV (Nagar Nigam Varanasi). Informal focused group discussion, PRA (Participatory Action Research), and observation technique were applied to get the first hand information about the water supply scenario in the city. In the second phase of the study, Arc GIS 10.1 software was used to create maps for estimation of water supply management. The population growth in Varanasi from 2011 to 2041 is estimated to have a growth of 21% in 30 years at a rate of 2.25 % per year. This growth rate is considered in the model from 2011 to 2041 to predict the water demand in the city. The data was collected from various municipalities as per the office records. It is estimated that the amount of drinking water requirement forecasted for 2021, 2031 and 2041 is 0.49, 0.76 and 1.17 Billion liters per day respectively in Varanasi City. These data show that with an increase in population, the water demand is also increasing decade after decade. Increasing population growth rate, decreasing surface water resources, overexploitation of groundwater, deterioration of ground water quality and poor sewage treatment are the major water supply related issues in Varanasi city, India.