Abstract. We present here the results of a 4-year environmental monitoring program at Ascunsȃ Cave (southwestern Romania) designed to help us understand how climate information is transferred through the karst system and archived by speleothems. The air temperature inside the cave is around 7 • C, with slight differences between the upper and lower parts of the main passage. CO 2 concentrations in cave air have a seasonal signal, with summer minima and winter maxima. These might indicate the existence of an organic matter reservoir deep within the epikarst that continues to decompose over the winter, and CO 2 concentrations are possibly modulated by seasonal differences in cave ventilation.The maximum values of CO 2 show a rise after the summer of 2014, from around 2000 to about 3500 ppm, following a rise in surface temperature. Using two newly designed types of water-air equilibrators, we were able to determine the concentration of CO 2 dissolved in drip water by measuring its concentration in the equilibrator headspace and then using Henry's law to calculate its concentration in water. This method opens the possibility of continuous data logging using infrared technology, without the need for costly and less reliable chemical determinations. The local meteoric water line (δ 2 H = 7.7 δ 18 O + 10.1), constructed using monthly aggregated rainfall samples, is similar to the global one, revealing the Atlantic as the strongly dominant vapor source. The deuterium excess values, as high as 17 ‰, indicate that precipitation has an important evaporative component, possibly given by moisture recycling over the European continent. The variability of stable isotopes in drip water is similar at all points inside the cave, suggesting that the monitored drip sites are draining a homogenous reservoir. Drip rates, as well as stable isotopes, indicate that the transfer time of water from the surface is on the order of a few days.

Abstract. We present here the results of a four year environmental monitoring program at Ascunsă Cave, Romania, intended to understand how climate information is transferred through the karst system and archived in speleothems. The air temperature inside the cave is around 7 °C, with slight differences between the upper and lower parts of the main passage. Relative humidity measurements were hampered by condensation on the capacitive sensors we used, thus we consider it to be close to 100 %. The local meteoric water line (δ2H = 7.7 δ18O + 10.1), constructed using monthly aggregated rainfall samples, is similar to the global one, revealing the Atlantic as the strongly dominant vapor source. The δ2H excess values, as high as 17 ‰, indicate that precipitation has an important evaporative component, possibly given by moisture recycling over the European continent. CO2 concentrations in cave air have a seasonal signal, with summer minima and winter maxima. This might be indicative of an organic matter reservoir deep within the epikarst that continues to decompose over the winter, possibly modulated by seasonal differences in cave ventilation. The maximum values of CO2 show a rise after the summer of 2014, from around 2000 ppm to about 3500 ppm. An analogous rise is seen in drip water stable isotopes and chemical elements such as Sr and Mg. The variability of stable isotopes and chemical elements is similar at all points inside the cave, indicating that they are draining a homogenous reservoir. Using two newly designed types of water/air equilibrators we were able to determine drip water dissolved CO2, by measuring its concentration in the equilibrator headspace and then using Henry's law to calculate its concentration in water. This opens the possibility of continuous data logging using infrared technology without the need of costly and less reliable chemical determinations.

As a living environment or biotope of the human species, urban structures must meet not only the economic, social and political rights of the people, but also their biological and neurophysiologic requirements. A new scientific approach to urban planning is biourbanism or organic urbanism, which considers the urban environment as being a hyper-complex living thing. From the scientific point of view, this approach opens the way to new scenarios for urban planning research. The aim of the study is to promote this modern concept of urban planning for Bucharest City in the context of its climate vulnerability. The objectives of our investigation are the following: analyzing the dynamic of climate conditions of the city, highlighting the weather risks for the population and devising scenarios for implementing the concept in Bucharest. The research methodology focused on the following: the discussion of conceptual framework based on specialty literature, the calculation of bioclimatic indices in order to assess the city's vulnerability to climate conditions and the presentation of "biourban" improvement models applicable to urban fabric samples. The study reveals the vulnerability of Bucharest City in relation to the specific risks associated to the weather phenomena of the summer season (high temperatures and moisture deficit), as argument in favour of preparing implementation scenarios for biourbanism ideas.

No abstract

No abstract