The amendments may be natural or synthetic and by their origin organic or inorganic. Among amendments, the inorganic ones are recommended, such as gypsum, lime, zeolites and altered rocks, including sand, ceramic, perlite, ash, slag, zeolite, pyrites, dolomite, calcined clay, etc. Fly ash-based zeolites can be used as amendments to improve the use of the soil for agricultural purposes. Generally, there are different methods for the synthesis of new materials using solid waste -fly ashes. Methods are known to be composed of a single stage or two stages. The first method -the conventional -is direct hydrothermal conversion of the mixture of ash and alkaline solution (NaOH or KOH), but only 50% of ashes can be converted into zeolite. The second method consists in mixing the ash with KOH and fusion at elevated temperature. The method leads to an advanced conversion -the type of zeolite depending on treatment conditions. Other studies recommend the conversion of ash using microwave ovens or ultrasound bath; in this case, the conversion time is reduced to 1-2 hours. From these methods, the direct method was proposed to be used in synthesizing zeolites for agriculture, with a part in controlling release of fertilizers and as a soil amendment. The synthesized materials were characterized with respect to microstructure (electronic microscopy SEM) and chemical and mineralogical composition (EDAX, X-ray diffraction). By analyzing the obtained data, one may observe the destruction of the ash network and crystallization of the zeolitic phase, especially in the case of treatment by diffusion. The XRD analysis confirms the presence of zeolite in materials obtained. Good results were also obtained in the case of using ultrasound treatment for zeolite synthesis; also, the time of treatment significantly decreased in this case.

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There is a great need for an efficient geographic information system (GIS) implementation in interdisciplinary domains for providing useful information for scientific and managerial processes of further improving land-use planning and decision making in horticulture. The main goal of this study was the creation of a digital map and GIS application for the Fruit Research Station in Cluj-Napoca, NorthWestern Romania. The benefit of this implementation is a fully integrated land information system, where information is accessed omnipresent for processing, value adding and further analysis. The created model is as a modern solution for obsolete analogue maps, sketches, inventory and land records that are usually unreliable and poorly represented in agricultural productive units. Using the created GIS database and spatial analysis there were obtained a very useful orchard mappings that incorporate management and economical attributes essential in land planning. Future focus and development will be mainly on system maintenance, including system enhancement and upgrading rather than to create a new systems. Under the constant pressures of urban sprawl and land degradation in this area, the paper conducts towards a guideline and model for an effective use of land resources to the best advantage and capacity.

In the highly populated analysed territory, the expansion of the construction zones and the pressure imposed on the slopes by the housing and transport infrastructure led to the appearance and reactivation of mass movement processes that affects the population and the environment. The purpose of this study consist in applying the principles of bivariate statistical analysis in order to determine the dynamic potential of a territory, taking into account the statistical relationship between the independent variables represented by predisposing and triggering factors of landslides (slope, geology, land use etc.) and dependent variables, in this case: landslides. The identification of the degree of validation of the results was determined by calculating the AUROC (Area under the Receiver Operating Characteristic) value, whose value of 0.854 highlights the representativeness of the chosen model. The analysis of landslides susceptibility highlights the inclusion of the territory represented by the hills surrounding Cluj-Napoca metropolitan area, Romania, on the classes of spatial occurrence of these processes.

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The functions and conventional roles of the forests have to be largely reconsidered when such forests are located in the close proximity of urban centres. The subject of this study was to evaluate different natural risks, especially landslides at an experimental study area that is located in Făget Forest, near the city of Cluj-Napoca, North-West of Romania. Although most of this area is stabilized, human activity became in the last period the most aggressive and active factor that can induce changes in slopes stability. The evaluation based on new changes at the terrain and constructions has clearly revealed the effect of the unprecedented urban sprawl and the expansion of infrastructure elements and residential buildings. Landslide susceptibility map was elaborated using a bivariate statistical analysis and the Geographical Information System (GIS) technology on a predetermined path inside the forest, as well as obtaining valuable information about the tree species. Based on 14 surveys, each of them covering an area of 500 m 2 on a longitudinal transect of the forest, there were identified relatively few tree species with a significant share: Carpinus betulus (42.9%), Fagus sylvatica (24.9%), Quercus petraea (23.2%) and other species (9%). Their positive roles in avoiding or limiting the flow on slopes, flooding, landslides are different depending on the position, terrain, forest composition, trees density, slope, exposition, but it is fundamentally beneficial. Furthermore, these species can assure productive (as wood), ameliorative, ecological, landscape, cultural, educational, relaxation roles, and consequently inestimable values.

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