The paper presents a series of results regarding the application of GNSS technology for measuring displacements to earth dams. An appropriate horizontal and vertical deformation-tracking network must be established for the rapid monitoring of earthmoving movements. Data obtained from the monitoring network can be used in the earth dam stability analysis program. Periodic tracking of earth dams using GNSS technology provides high accuracy of spatial distortions. The results of the paper show the application of GNSS technology to monitor the deformations of the Podisu earth dam located on the Sheep Valley River in Iasi County. In the first stage of research (2019 and 2020), the local geodetic tracking network was created. To monitor the dam, four control landmarks were placed on the crest of dam and seven landmarks on the downstream slope. In the second stage of the research (year 2021) the measurements of the displacements at the earth dam were performed. The GNSS monitoring method has the advantage of positioning the target quickly, statically, and with high accuracy. The measurements used fixed stations located at two points in the local geodetic network. Four Trimble GNSS receivers were used for the measurements. The resulting data was processed using the Trimble Business Centre program. The obtained results were analysed in comparison with those existing in the design documentation and technical expertise of the dam. The results highlight the presence of displacements on the crest of a dam and slopes of the dam. The final findings highlight the performance of GNSS technology in the monitoring process, where it provides millimetre-accurate accuracy with high spatial and temporal accuracy.

The paper presents the current way of elaboration of the topographical and cadastral documentation needed in the process of tracking the behavior of hydrotechnical constructions such as earth dam. The studied area is represented by the accumulation of Pârcovaci located in the Deleni territorial administrative unit in Iași county. Using topo-geodetic measurements the magnitude of the vertical displacement of the studied construction were determined. The measurements were performed during the exploitation period of the dam, during 23 series of observations. Thus, there were highlighted the displacements of landmarks located on coping dam, downstream slope and outlet tower. Charts of evolution over time of vertical deformation have been made according to field observation. Also, the suface of the land corresponding to the whole of the accumulation of Pârcovaci was registered at Office of Cadastre and Real Estate Advertising Iași, through first registration documentation. This has made precise spatial delimitation of the set of lands and construction of studied area, and the whole land was recorded in the land book by assigning a unique cadastral number.

In this paper we tried to study the values of radiant temperatures (Land Surface Temperature) and NDVI (Normalized Difference Vegetation Index) for areas occupied by buildings and green spaces. The area affected by the Urban Heat Island (UHI) was also determined. Study Area, Iasi, the largest city in eastern Romania, is geographically situated on latitude 47°12'N to 47°06'N and longitude 27°32'E to 27°40'E. LST is an estimate of ground temperature and is important to identify change in environment. An important parameter in global climate change is rapid urbanization which leads to an increase in Land Surface Temperature (LST). The urban heat island (UHI) represents the phenomenon of higher atmospheric and surface temperatures occurring in urban area or metropolitan area than in the surrounding rural zones due to urbanization. It also been found that night UHI is more powerful than day. At night the LST values for SUHI varies between 24.5°C-25.9°C, and during the day between 35°C-38.7°C. With the development of remote sensing technology, it has become an important approach to urban heat island research. MODIS and Landsat data were used to estimate the LST and NDVI. From the analysis of the images it can be seen that the temperatures in SUHI are lower where there are green spaces around the buildings, and temperatures are higher in the non-UHI area, where inside or around the green spaces there are surfaces built or covered with concrete. Statistical data show very average temperatures for areas affected by UHI, 37.8°C for daytime and 24.6°C for night.