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Long term productivity and conservation of soils is critical for sustaining agricultural ecosystems. The specific objective of the work reported was to determine the effects of long term application of organic and mineral fertilizers on soil enzyme activity as an index of soil biology and biochemistry. Three key soil enzymes involved in intracellular metabolism of microorganisms and two soil enzymes involved in phosphorus metabolism were selected. Actual and potential dehydrogenase, catalase, acid and alkaline phosphatase activities were determined in the 0-20 cm layer of an eroded soil submitted to a complex fertilization experiment. Results showed that addition of mineral fertilizers to organic (green manure and farmyard manure) fertilizers led to a significant increase in each activity because of increased plant biomass production which upon incorporation stimulates soil biological activity. The enzymatic indicators of soil quality calculated from the values of enzymatic activities depending on the kind of fertilizers showed that by the determination of enzymatic activities valuable information can be obtained regarding fertility status of soils. A weak positive correlation between enzymatic indicators of soil quality and maize yield was established. The yield data demonstrate the superiority of farmyard manure which provided greater stability in crop production. Substantial improvement in soil biological activity due to application of organic fertilizers with mineral fertilizers contribute in maintaining the productivity and soil health.

Soil enzymes activities have been considered as sensitive indicators of alteration soil quality by management. In order to obtain new data on the soil enzymological effects of soil management practices, we have determined some enzymatic activities in a preluvosoil submitted to a complex tillage and crop rotation experiment at the Agricultural Research and Development Station in Oradea (Bihor County). Actual and potential dehydrogenase, acid phosphatase and catalase activities were investigated in a split plot experiment where tillage (no-till and conventional tillage) was the main plot and crop rotation (Wheat/Maize, W/M; Soybean/Maize, S/M; Oats-Clover/maize, O-C/M) was the subplot. Soil samples were taken at 0-20, 20-40 and 40-60 cm. Each activity in both non-tilled and conventionally tilled soil under maize crop decreased with increasing sampling depth. It was found that no-till, in comparison with conventional tillage, resulted in insignificantly higher (p]0.10) soil enzymatic activities in the 0-20 cm layer and insignificantly (at least at p]0.10) lower activities in the deeper layers, excepting actual and potential dehydrogenase activities in the 40-60 cm layer, in which these activities were significantly lower(0.02]p]0.01). Based on the absolute values of the enzymatic activities, the enzymatic indicator of soil quality (EISQ) was calculated. The EISQ values ranged between 0.201 and 0.974 indicating the presence of high enzymatic activities in the upper layer and a moderate intensity of the enzymatic activities in the deeper layers. A significant correlation between soil enzyme activities and physical and chemical indicators was established.

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Chemistry in agriculture has been considered for several decades a formula synonymous with progress and development, as chemical engineering, mechanization, irrigation, modern agro-technical processes have contributed to a substantial increase in production. At present, the use of pesticides to increase agricultural productivity is considered to be a global hazard to the environment. This study examines changes in tree tolerance for major diseases and pests, disease and pest behavior, and the changes that occur in the recommended pesticide treatment. The researches were carried out on different species of fruit trees (apple, plum, and almond), cultivated in an intensive system, in five orchards located in Bihor county. The behavior of each species, as well as the behavior of different varieties with respect to tolerance to major diseases and pests, have been observed over the last 5 years (2013-2017). In addition, pesticide residues were monitored from all crops of apple, plum and almond. During 2015-2017, from March to May, the diseases were more virulent, requiring intensive intervention with systemic and contact fungicide combinations to achieve optimal efficiency; this fact has been correlated with the increase in the number of samples containing pesticide residues. This perspective allows an ecological remodeling of current progress in orchard development, including all aspects of environmental protection and the impact on population2 s health.

Grape skin is considered a valuable by-product for antioxidant and antibacterial agent preparation. The grape skin contains some active compounds, such as, dietary fiber, polyphenols, flavonols, and resveratrol; it is commonly used as a nutritional supplement. The main aim of this study was to establish the optimum dose of grape skin flour, to be used as a functional ingredient in the bakery products industry, from both chemical and rheological point of view. The laboratory experiments evaluated the functional potential of wheat flour enriched with grape skin flour, in different proportions, by examining the chemical composition and rheological behaviour of the doughs. Protein, crude fibre, fat, ash and mineral contents were determined. Using �H-NMR spectral technique, the fatty acids composition was determined, especially the concentrations of short-chain saturated fatty acids (C4-C8), di-unsaturated fatty acids, mono-unsaturated fatty acids and long-chain saturated fatty acids (]C8). 1H-NMR spectra were recorded on a Bruker Ascend 400 MHz spectrometer. The rheological behaviour was analyzed using the predefined Chopin + protocol on Mixolab, an equipment of CHOPIN Technologies. Grape skin flour was incorporated into wheat flour at three different levels, 5, 10 and 15% and it was found that incorporation up to a 15% level into the formulation of wheat flour yielded an acceptable product in terms of rheological parameters, with improved chemical, nutritional and functional properties.

Fagus sylvatica is widely distributed across Europe thanks to its high adaptability in a wide variety of soils and climate. Microbial communities are essential for maintaining forest soil quality and are responsible for forest ecosystem functioning; the ability of soil microorganisms to respond to abiotic stressors (e.g. organic carbon losses, water scarcity, temperature changes), is crucial under ongoing environmental changes and also supports tree health. In this study, soil samples were collected from pure beech plots as part of the COST Action project CLIMO to find differences in microbial community characteristics and evaluate the effects of soil properties on microbial communities across altitude, latitude and longitude gradients. Positive relationships were found between organic carbon content and both microbial abundance and dehydrogenase activity. Dehydrogenase and catalase activities were altitude-correlated and microbial activities were longitude-correlated. In the most southern beech plot, microbial community was abundant and displayed high activities. This shows that microbial communities could help tree populations to better adapt to predicted changes in environmental conditions in the future. We suggest that research into forest health and beech performance should also test soil microbial enzymatic activity, in particular under changing climate conditions, to assist in identifying adaptation strategies.

In this paper we provide new data about the soil enzyme activity as a biological process, which is an indicator for impacts of factorial combinations of lime and fertilizers applications. Five plots divided into fifteen subplots were sampled for determination of the enzymatic indicators of soil quality, based on the actual and potential dehydrogenase and catalase activities. The research revealed that limed soil samples, in comparison with unlimed ones, resulted in significantly higher soil enzymatic activities (p[0.05) in the upper (0-20 cm), while in the deeper (20-40 cm) layer, only catalase activity was significantly higher (at least at p[0.02). Mineral fertilization, in comparison with its farmyard manuring, led to an insignificant increase in each of the three enzymatic activities determined, excepting catalase activity which was significantly higher (0.05]p]0.02) in the 0-20 cm layer. Based on the absolute values of the enzymatic activities, the enzymatic indicators of soil quality (EISQ) were calculated. The mineral NPK-fertilization and low dose of lime in the 0-20 cm layer, and mineral NP-fertilization and low dose of lime in the 20-40 cm layer proved to be the best variants of fertilization. The enzymatic indicators of soil quality in these variants reached the highest values: EISQ=0.821 and EISQ=0.889, respectively, indicating the presence of high enzymatic activities. It should be emphasized that a balanced application of lime, mineral fertilizers and farmyard manure leads to the formation of favorable conditions for the development of microorganisms, growth of plants and for an intense and lasting enzymatic activity.