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Abstract

The increased use of Holstein genetic material in the Irish dairy herd has consequences for beef production. In all, 42 spring-born steers [14 Holsteins (HO), 14 Friesian (FR) and 14 Charolais × Holstein-Friesian (CH)] were reared to slaughter at between 26 and 37 mo of age. Carcass weight was higher and the lipid concentration of m. longissimus thoracis et lumborum was lower (P < 0.05) for CH than the dairy breeds. Overall acceptability tended to be lower (P = 0.055) while tenderness, texture and chewiness were lower (P < 0.05) for CH compared with the dairy breeds. The proportion of C16:1 in the total lipid tended to be lower (P = 0.055) for CH than the dairy breeds. Replacing male offspring of traditional “Irish” Friesian bulls with offspring from a genetically superior (from a dairy perspective) strain of Holstein bull had no commercially important impact on beef nutritional or eating quality.

Abstract

The impact of regulated drip-irrigation on productivity and fruit quality of tomato ‘Tofane’ has been studied under a warm dry desert climate in southern Algeria. Yield, fruit weight and size, water content and parameters of fruit quality – total soluble solids, phenolic compounds, carotenoids, vitamin C, pH and titratable acidity were determined. Two irrigation treatments were applied in 2012 and 2013: T1, optimal irrigation (100% evapotranspiration – ETc) during the whole growth period (growth stages I, II and III); T2, optimal irrigation during I and II stages, and regulated deficit irrigation (67% ETc) during stage III (from fruit set to full fruit maturity of first and second bunch). T1 treatment during the whole season showed the highest values of soil water potential (Ψsoil), between −0.02 MPa and −0.06 MPa, on depths of 0.3 and 0.6 m, respectively. During stage III, regulated deficit irrigation caused the lowest Ψsoil values, which were between −0.1 MPa and −0.12 MPa on a soil depth of 0.3 and 0.6 m, respectively. Deficit irrigation caused significant decrease of water content in fruits and not significant decrease of fruit weight and size, as well as fruit yield while water saving for irrigation amounted to 10%. Comfort-irrigated tomato plants produced fruits containing significantly higher titratable acidity, total soluble solids and vit. C content. There was a tendency to decrease carotenoid content and increase phenolic content in both years of the study. Due to the possibility of water saving with not significant yield decrease, it seems that the reduction of water use in growth stage III would be an adequate strategy for tomato cultivation in hot, dry climate.

Abstract

Ultrafiltration of skim cow’s milk with a UF10-PAN membrane at volume reduction ratios (VRRs) of 2 and 3 was performed. The ultrafiltration retentates obtained were used for production of probiotic yoghurts with three different starters. A control sample was prepared using skim cow’s milk. All yoghurts were analysed according to the following parameters: titratable acidity, dry matter, organoleptic characteristics, number of specific microorganisms (Lactobacillus bulgaricus and Streptococcus thermophilus) and the total count of viable lactic acid bacteria for 28 d of storage. The results showed that the increase in the VRR during ultrafiltration increased the titratable acidity, as well as the dry matter of all yoghurts. Ultrafiltration concentration led to an increase in the count of viable lactic acid bacteria in all yoghurts which improved their functional properties. The highest values of the total number of viable lactic acid bacteria were determined in yoghurts obtained with starter 1CM, followed by starters MZ2 and ZD for both VRRs. Probiotic yoghurts with the highest organoleptic evaluation were obtained from ultrafiltration retentates at VRR = 2 and starters 1CM and MZ2.

Abstract

The properties of biomass-based fuel and combustion tests showed that logging residues are promising renewable energy sources. The data used in this study were collected from four clear-felling areas in Järvselja Training and Experimental Forest Centre, Southeast Estonia in 2013–2014. Logging was carried out by harvesters in Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies [L.] Karst.), silver birch (Betula pendula Roth.) and black alder (Alnus glutinosa L. Gaertn.) dominated stands with a small admixture of other tree species according to the cut-to-length method and logging residues were placed in heaps. The aim of this research is to assess different characteristics of logging residues (quantity, moisture content, energetic potential, ash content and amount) in clear-felling areas. The highest load of slash was measured on the birch dominated study site, where the dry weight of the logging residues was 29 t ha−1. Only the branch fraction moisture content on the black alder dominated site (35.4%) was clearly different from respective values on other sites (21.6–25.4%). The highest calorific value of the residues was assessed with the residues from the birch dominated site, where in moist sample it was 365 GJ ha−1 and in dry matter 585 GJ ha−1. The heating value of the fresh residues is highest in coniferous trees. The highest ash content in branch segments was registered for the black alder dominated site. Järvselja data indicate higher quality in conifer dominated sites, yet a higher load of logging residues in broadleaf dominated stands.

Abstract

This study focused on the occurrence of xylophagous beetles and nematodes in the different parts of Pinus sylvestris L. trees of different health condition in the pure stands in Zhytomyr region (Central Polissya). Stem fragments with thin, thick and transitional bark, branches and twigs were examined in each of 12 model trees. Xylophagous beetles were identified by adults or by galleries. Nematodes were isolated from wood samples in the laboratory using the Baermann method and identified by morphometric characteristics. Among 10 species of xylophagous beetles, Ips acuminatus (frequency 16.7%; dominance 17.9%) and I. sexdentatus (frequency 11.1%, dominance 54.6%) dominated, which prefer the fragments with thin and thick bark respectively. No xylophagous beetle was found in the healthy and slightly weakened trees. Among 15 nematode species, 40% were saproxylic, 33.3% entomophilic, 13.3% phytophagous, and by 6.7% predators and species associated with fungi. An entomophilic nematodes Cryptaphelenchus macrogaster f. acuminati was common in all parts of stem and branches (frequency of occurrence 25–33.3%). An entomophilic nematodes Parasitorhabditis acuminati and a predator Fuchsia buetschlii acuminati had the highest frequency of occurrence (41.7%) under the thin bark and in the branches. The frequency of these species in colonized with xylophagous insects stem fragments with thin bark was significantly higher than in respective not colonized fragments.

Abstract

The argan tree is a multi-purpose tree (fruit tree, medicinal, cosmetic, and pastoral plant) found in the semi-arid and arid regions of North Africa. It is under strong human pressure such as the impact of population growth, crop expansion, overgrazing, and wood and fruit exploitation that are also the main causes of desertification in the rest of the world. Over the years, interest in this beneficial tree and demand for its products have increased: especially with the increase in the price of argan oil, which is now one of the most expensive and much in demand oils in the world. This increase has led to many socio-political, economic and cultural changes at the national, regional and local levels, especially in farming behaviour and the habits of the local population. This bibliographic research was therefore conducted in order to analyse the various changes and their consequences on the planning, conservation, and management methods implemented in the argan tree area and their effects on the habits of the local population in order to ensure the sustainability of the Argan Tree Biosphere Reserve in Morocco. Indeed, the aims of this study were, firstly, to analyse the change dynamic of argan forest area in the ABR; and secondly, to investigate the impact of various socio-political, economic and cultural changes resulting from increased prices of argan oil on planning, conservation, and management methods of argan tree ecosystem and on the habits of the local population.

Abstract

Over the years, it has been the subject of discussions whether efficiency-oriented interventions contribute to an equity distribution of wealth across regions and whether equity orientation is a source of inefficiency. While efficiency refers to the maximization of growth in the national economy, convergence-oriented policy is focused on equalizing the level of development at interregional level. The case of Georgia was studied as a developing country facing various challenges in terms of economic growth and regional divergence. This article provides an overview of the economic development trends taking place in the regions of Georgia and reveals the high level of divergence within the country. A logarithmic model was created and used to run simulations to predict the possible results of convergence-oriented policy in Georgia. In order to make the forecast we estimated GDP per capita and average growth rates in all the Georgian regions. Use of the model allowed us to answer two main questions: (1) If the last 5 and 10 year average growth rates are maintained, how long will it take for the poorest region to converge to the wealthiest one? (2) What should be the minimum growth rate in the poorest region for the upcoming 5, 10 and 20 years in order to converge to the wealthiest capital? Results of the calculations showed that convergence between regions can only be achieved by slowing down economic growth in relatively wealthier regions and by focusing on the development of the poorest ones. The results of the study revealed that the convergence process will be faster for the regions with medium or big cities and growth centres. Therefore, creating competitive growth centres would be a reasonable regional policy objective to promote fast economic growth and future convergence without redirecting the growth process from more developed areas to lagging ones.

Abstract

Norway spruce (Picea abies [L.] Karst.) and silver fir (Abies alba Mill.) are main tree species of Central Europe that are currently highly vulnerable in times of global climate change. The research deals with the effect of climate and air pollution on radial growth of silver fir and Norway spruce in mixed age-varied (56 – 146 years) forests in the Jeseníky Protected Landscape Area, the Czech Republic. The objectives were to evaluate biodiversity, structure and production, specifically interaction of radial growth of fir and spruce to air pollution (SO2, NOX, tropospheric ozone) and climatic factors (precipitation, air temperature). Concentration of SO2 and NOX had negative effect on radial growth of fir, while radial growth of spruce was more negatively influenced by tropospheric ozone. Fir showed higher variability in radial growth and was more sensitive to climatic factors compared to spruce. On the other hand, fir was relatively adaptable tree species that regenerated very well when the pressure of stress factors subsided (air pollution load, Caucasian bark beetle, frost damage). Low temperature was a limiting factor of radial growth in the study mountainous area, especially for fir. Fir was significantly sensitive to late frost, respectively, spruce to winter desiccation and spring droughts with synergism of air pollution load. Generally, older forest stands were more negatively influenced by air pollution load and climatic extremes compared to young trees.

Abstract

The study was conducted in pure Scots pine (Pinus sylvestris L.) forests and mixed forests of Scots pine and silver birch (Betula pendula Roth.) within the Chernihiv Polissya physiographic region of Ukraine. The aim of the study was a comparative analysis of forest mensuration characteristics and health condition of pine and mixed pine-birch stands planted on formerly arable lands and cutover areas after pine stands infected by annosum root rot. It was found that in pine stands planted on formerly arable land, the average diameter of living trees in the root rot disease focus was 1–6% larger and the average diameter of dead trees was 11–23% larger than those outside the disease focus. Due to the pathological loss inside the disease foci, the pine stand density was much lower – by 14–38% and the growing stock volume was 16–35% less as compared to the outside areas. Mixed pine-birch stands (with a predominance of pine trees), established on the cutover areas after pine stands affected by root rot, had a 20% greater stock volume and the birch-pine stands (with birch predominance) in the clear-cuts had 18% greater stock volume than pure pine stands inside the root rot disease area. The pine trees were assessed as “weakened” in the mixed stands and as “severely weakened” in the pure pine stand inside the disease focus. The birch trees in mixed stands were characterized as “healthy”.

Abstract

Climate change is a major global issue, which is becoming increasingly important on the international scene. As it has a direct impact on ecosystems and societies. Water is at the heart of these changes. The aim of this article was to capture all the microeconomic and macroeconomic effects of resource availability, and to propose a sequential dynamic computable general equilibrium (CGE) model that takes into account long-term changes in the availability of the primary resource (water supply) with regard to population growth (demand). The results show that the very negative effects on the economy of water shortages could be counteracted by the introduction of a marginal cost demand management policy. This makes it possible to better manage the scarcity of this resource. In fact, the model shows that when Algeria is facing water deficits, the marginal cost tariff policy reverses the trends of an economy that would maintain a tariff policy at average cost. Total investment increases, and total welfare deteriorates less. The drop in the price of water (input and final good), generated by the transition from an average cost pricing to a marginal cost pricing, generates an expansion of many sectors, and stimulates economic activity which reduces the rate of unemployment.