Volume XVII |

Soil pollution prevention and control measures in China

Abstract: Soil pollution is a major problem in China. This paper de-scribes the policies that the government has undertaken to remedy the situation, by either preventing additional pollution, or reducing the existing pollution levels. First, China is honing the legal framework to protect arable lands, control sources of pollution, and assess, manage and clean up polluted sites. Second, the government has made steps to improve the identification and monitoring of pollution sources. Third, the government has promoted chemical and biological technologies to lower the level of soil pollution. In spite of these efforts, there are still considerable challenges. First, China has considerable economic, social, and environmental diversity, so uniform top-down designed policies are likely to face considerable problems in many areas. Second, the local institutions trusted with the soil pollution cleanup have little understanding about clean soil standards, the right technology for soil inspection and treatment, and the management strategies for vast areas of land. In addition, the costs of cleaning up the land are staggering, with estimates ranging from CNY 6 to 11 trillion, with little potential for cost recovery from soil rehabilitation.

Volume XVII |

Lateral migration of the Jiu river course between 1864 and 2018. Case study: Craiova – Zăval sector

Abstract: During the last 154 years, the Jiu river course that stretches from its confluence with the Amaradia down to the outlet has undergone serious lateral and length changes. The main purpose of this article is to highlight these changes, to determine their magnitude, and to understand the future evolution of the Jiu course.
The results of our analysis showed that from 1864 until 2018, the Jiu river became shorter in the lower section, decreasing with 38.1 km, from 134 km to 95.9 km. The shorten-ing of the course happened gradually. Thus, between 1864 and 1910, the length of the course decreased by 25.6 km, from 134 km to 108.4 km. From 1910 until 1970 there was a shortening of 11.9 km and between 1970 and 2018, the river shortened its course by about 0.6 km. The greatest lateral distance between its historical and present channels showed a maximum of 11.22 km on the outlet.

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.