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The timing and lowering type of walnut genotypes (Juglans regia L.) is one of the important factors that lead to high and constant production. Therefore, the selection of homogame and spring frost tolerant genotypes has been among the most important priorities in breeding programs of walnut. The present paper analyzed the degree of dichogamy and the flowering time of 19 promising genotypes in walnuts from the sandy area, the S-V Oltenia region, Romania. Observations made over two calendar years have shown that the flowering period is influenced by environmental factors, especially temperature. The flowering time has changed from one year to the other, the high temperatures in spring accelerate the evolution of the male flowers,but the female flowers are not greatly influenced by these temperatures. Thus the type of flowering was not constantly, changing according to the climatic conditions of the two years. Knowing the type and timing of flowering of walnut genotypes is very important for pollination, because homogamy types are quite rare in the analyzed population.

Micro and macroalgae are renewable and carbon-neutral sources of energy that can grow naturally or can be cultivated in nutrient-rich wastewater, without compromising the production of food crops. Microalgae use nutrients, accumulate heavy metals and reduce coliform bacteria from wastewater, thus contributing to their phytoremediation. Furthermore, the conversion of algae biomass into biofuels contributes to reducing the dependence on fossil fuels and greenhouse gas emissions in the atmosphere. Depending on the species and cultivation method, microalgae have a very fast growth rate (12 days) and their potential to produce biodiesel is 15 to 300 times higher than that of agricultural and energy crops conventionally used for biofuels. Lipid content in microalgae can reach 75-80% by weight of dry biomass. To produce 39 billion liters of biodiesel, 15 million tons of nitrogen and 2 million tons of phosphorus are required during the growth process of microalgae. From algae cultivated in 500 billion m3 of industrial wastewater, approximately 37 million tons of oil can be extracted that can be transformed into biodiesel. However, there are also challenges in large-scale utilization of microalgae, due to the high energy input, technical difficulties encountered in harvesting unicellular microalgae, and the need for subsequent pretreatment operations to improve lipid extraction. This paper reviews the potential of microalgae species to thrive in wastewater and the technological achievements in converting microalgae biomass for the sustainable biodiesel production. [ABSTRACT FROM AUTHOR]

The differences between the phenology of plants in rural and urban areas are the subject of research all over the world. The aim of this study is to assess the impact of urban conditions and distance from the town center on the phenology of ornamental species: Forsythia x intermedia; Mahonia aquifolium; Spiraea x vanhouttei; Albizia julibrissin; Syringa vulgaris; Chaenomeles japonica, Aesculus hippocastanum; Prunus cerasifera; Catalpa bignonioides; Tilia tomentosa. The study assesed the date of average onset of individual phenological phases of some ornamental species, analyzing the variability of dates when bud-bursting, flowering and fruit-setting occur, in relation to the two areas analyzed, namely the town center and a neighboring area located 5 km from the town center. In order to compare the bud-bursting (09 BBCH), the first open flowers (60 BBCH), the end of flowering (69 BBCH) and the ripe fruit (89 BBCH), the F-Test Two - Sample for Variances test was used. The results show the variation of phenological phases from one species to another, from one area to another and the influence of urban environment on phenology, on vegetation season of the analyzed species, each phenological phase starting earlier in the town center compared to the neighboring area, 5 km away. [ABSTRACT FROM AUTHOR]

The aim of this study is to provide information on the phenology of urban spring season, of some species of ornamental trees and shrubs, in the light of climate changes occurred over the recent decades. Ten species of ornamental shrubs and trees cultivated in two areas of a town located in southwestern Romania were studied. It was found that the spring season phenology of the studied species is dependent on the climatic year, in recording differences between the number of days from November 1 and the beginning of each spring phenophase, both from one species to another and from one climatic year to another, and also from one area to another; the spring phenology starting earlier in the urban area regardless of the species and the climatic year. Higher temperatures, rising from one year to another, are speeding-up the onset and development of spring phenology, regardless of species, and the urban climate through the effect of urban heat island leads to even earlier onset of spring phenophases and shortening of the growing season, so that by phenological differences existing within the species from one climatic year to another and from one climatic zone to another, spring season phenology can be considered an indicator of temperature rise. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the response of the plum rootstock 'Fortival' to the action of rooting biostimulators, using semi-hardwood cuttings. The experience was located in a solarium equipped with artificial mist installation. The cuttings were treated with different hormones (IBA, NAA and Radistim no.2) and reported to control. The results show that among the biostimulators applied to 'Fortival' rootstock cuttings, Radistim no. 2 had a superior influence on the development of the root system, compared to both the control and the other used biostimulators, determining the highest rooting percentage, the highest number of roots, the highest average length of roots/cutting, the highest average length of the rooted segment and the largest volume of roots. The F-Test Two-Sample for Variances shows that the variance of the average length of roots/cutting is higher in the case of chemically treated cuttings, regardless of the used biostimulator, which shows the favorable response of 'Fortival' rootstock to the application of rooting biostimulators used in the study. [ABSTRACT FROM AUTHOR]

The main aim of this paper is to establish how urban environment conditions do influence the development of shrub ornamental plants in terms of their phenology. Spring season phenology of six species of ornamental shrubs and four of trees from an urban area of Muntenia, Romania, was analyzed under the influence of temperature. The analyses were made using correlations and the cold hours accumulated by species were calculated until the flowering bud breaking. The results obtained show that temperature significantly influences the onset of spring phenological phases and their duration. The research will be going on focusing on changes that occur in phenology of species from one year to another, under the influence of variable climatic conditions from year to year, in order to highlight the effect of climate changes on urban phenology. [ABSTRACT FROM AUTHOR]

Waste treatment involves all chemical, physical and biological processes that have the role of modifying certain characteristics of the waste in order to reduce their volume and hazardousness, thus facilitating their recovery. Among the available technologies, composting is presented as one of the most promising options for recycling the organic fraction into a valuable organic fertilizer called compost. In the present paper are presented the main composting methods, namely: passive composting in piles, turned windrow composting, passive aerated windrows, aerated static pile and in - vessel composting. [ABSTRACT FROM AUTHOR]

Anaerobic digestion is a biochemical decomposition process that is used for the treatment and energy recovery from biomass, like organic residues, agricultural and industrial wastes, animal manure and energy crops. The paper presents results of experimental research on the physico-chemical characteristics of the agricultural biomass (corn stalks, wheat straw and alfalfa) that can be used in co-digestion with animal manure in biogas plants. Parameters with a significant role in the process of anaerobic fermentation were assessed: total soluble solids (TSS%), the pH, the moisture content as well as the reducing sugars in the liquid fraction of the tested substrate. [ABSTRACT FROM AUTHOR]

Important challenges in the global water situation, mainly resulting from worldwide population growth and climate change, require novel innovative water technologies in order to ensure a supply of drinking water and reduce global water pollution. For this purpose, highly advanced nanotechnology offers new opportunities in technological developments for advanced water and wastewater technology processes. This paper presents an important method used in the wastewater treatment and in the mineral separation, named the flotation. Also, this paper presents the factors that influence the froth flotation process, such as: nanoparticle hydrophobicity, nanoparticle diameter, particle softness etc. [ABSTRACT FROM AUTHOR]