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The Analysis of the Chemical Composition of Precipitation During the Driest Year from the Last Decade

Abstract

In order to investigate the precipitation chemistry, studies were carried out from January 2013 to December 2013 in Odorheiu Secuiesc and Miercurea Ciuc, Eastern Carpathians, Romania. During a period of eleven years (2006 – 2016), 2013 was the driest year. The rainwater samples were analyzed for pH, major anions and cations. HCO3 concentrations were calculated based on the empirical relationship between pH and HCO3 . NH4 +, Ca2+, SO4 2− were the dominant ions in precipitation at both sites. The pH values varied from 6.75 to 7.46 Miercurea Ciuc, and from 6.69 to 7.67 in Odorheiu Secuiesc. The neutralization was mainly brought by Ca2+ and NH4 +. Estimated ratios of sea-salt fraction (SSF), non-sea-salt fraction (NSSF), and results from Spearman’s rank correlation and Principal Component Analysis (PCA), showed that the acidic ions (SO4 2−, NO3 ) were derived from anthropogenic activities, NH4 + from soil fertilization, while Ca2+, Mg2+, K+ originated from terrestrial source. These influence the precipitations ionic content, especially during droughts. Spatial variations and the rim effect of the Eastern Carpathians on precipitation chemistry is also shown.

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The Application of Directional Univariate Structure Functions Analysis for Studying the Spatial Anisotropy of Environmental Variables

Abstract

As anisotropy is a fundamental property of the real-world environmental spatial variables, the conventional omnidirectional variograms and correlograms do not provide means enough to characterise spatial dependence between observations. The purpose of this article is to introduce directional univariate structure functions analysis to explore and quantify the spatial anisotropy of environmental variables. Analysis of six environmental variables within three physical–geographical regions proved the leading role of relief for landscape differentiation; it also defined the size and extension of major landforms responsible for the organisation of spatial pattern. The arrangement of the vegetation patches demonstrated linkage with the major landforms. The other relief derivatives, being prone to noise and artefacts in the original data, showed a random-variable type of behaviour. In the lack of any particular spatially anisotropic structure, the results of the analysis can provide a clue about meaningful distances of interest at finer scales. The approach can also be an exploratory tool for discrete measurements to recognise the features of spatial continuity.

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Application of Geographic Information Systems for Flood Risk Analysis: A Case Study from Accra Metropolitan Area

Abstract

The main objective of the study was to identify high flood risk zones in AMA. The study also used questionnaires to assess local knowledge on what accounts for the high flood risk in their community. Spatial analysis techniques were used to model flood risk based on the following contributory factors; land cover, soil, drainage density, topography and proximity to rivers. The results show that high flood risk areas covered 46.3km2(20%), moderate risk area, 72.9km2(31.6%), low risk area 41.5km2(18%) and very low risk areas, about 6.7km2(2.9%). The high flood risk zones were low-lying areas below 50 meters above sea level and closely associated with poor drainage systems. People perceived not just low-lying areas as a paramount reason accounting for flooding but also very bad waste disposal habit of the public. These offsets the efforts of waste management companies to keep drains free of refuse.

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Approved genetically modified (GM) horticultural plants: A 25-year perspective

Abstract

In this review, we present genetically modified (GM) horticultural events that have passed the regulatory process and have been approved for cultivation or food use in different countries. The first authorization or deregulation of a GM horticultural plant issued 25 years ago initiated a fast expansion of GM organisms (GMO) engineered by using gene transfer technology. The list of GM horticultural species comprises representatives of vegetables, fruit plants and ornamentals. We describe their unique characteristics, often not achievable by conventional breeding, and how they were developed, and the approval process. Information on the adoption of GM horticultural cultivars and sale is accessed if commercialization has occurred. The review comprises, among others, Flavr SavrTM and other tomato cultivars with delayed ripening and improved shelf-life, insect-resistant eggplant (or brinjal), as well as virus-resistant squash, melon and the common bean, and also fruit trees, plum and papaya. Cultivation of the latter was particularly valuable to farmers in Hawaii as it ensured restoration of papaya production devastated earlier by the Papaya ringspot virus (PRSV). In contrast, a plum resistant to sharka (Plum pox virus; PPV) deregulated in the USA is still awaiting commercialization. GM events with improved quality include the recently marketed non-browning apple and high-lycopene pineapple. We also present orange petunia, blue ‘Applause’ rose and Moon-series carnations with a modified purple and violet flower colour. Finally, we discuss prospects of GM horticultural plants, including their development using promising new breeding technologies relying on genome editing and considered as an alternative to the transgenic approach.

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Aspects Regarding the Linseed Oil Culture in Romania in the Context of the Ongoing Climate Change

Abstract

Nowadays, at global level, the linseed oil culture is more important economically than the linseed cultures for fiber. The world's largest linseed production is the linseed oil, followed by the culture for the consumption of seeds and for fibers. In this context, this study presents the evolution and the main trends in the production of the linseed oil for Romania in the period 2008-2017, the analysis being based on the values of specific indicators, namely the areas cultivated with linseeds and the production of the linseed oil achieved at the national level, macro-regions and development regions, both as a total and in the private sector as well. This analysis will be done in the context of the ongoing climate change also affecting Romania's territory. Analysing the results, one can notice that, although after 1990 the cultivated areas have decreased dramatically, since the integration of Romania into the EU, the linseed oil cultivated areas have started to grow. Thus, in 2017, Romania was the sixth EU linseed oil producer in the EU, with the South-East region holding a significant share of the cultivated areas.

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Assessment of phenotypic plasticity of spruce species Picea abies (L.) Karst. and P. obovata (Ledeb.) on provenances tests in European North of Russia

Abstract

Phenotypic plasticity of 22 spruce provenances in three test plots located in the European North of Russia was studied. Parent spruce stands are located within the Russian Plain and are represented by Picea abies (L.) Karst., P. obovata (Ledeb.) and two introgressive hybrids. In the test plots located in the middle and southern taiga subzones P. abies provenances are tested northward of its distribution area and P. obovata provenances are tested within the distribution area and nearby its boundaries. phenotypic plasticity of the spruce provenances was assessed. Straight-line regression coefficient based on survival, diameter, and height was calculated. All provenances are divided into two groups: plastic and non-plastic provenances. High plasticity is observed more often for P. abies and hybrids forms with properties of P. abies. Plastic provenances based on three parameters grow in the Leningrad, Pskov, Vologda, Kostroma and Karelia. Area of parent stands growing is quite small-size and lies between 56º30´ – 61º40´ N and 30º30´ – 42º30´ E. Adaptive provenances of P. obovata and its related hybrids forms grow in the North-Eastern part of the Russian Plain that could be consequence of its distribution in Holocene. Picea abies being the more adaptive species would be more responsive to climate changes in terms of survival and growth rate than P. obovata. Therefore, in case of sustainable climate warming in the Northern areas of the Russian Plain, the further propagation and major distribution of P. abies with further competitive replacement of P. obovata can be expected.

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Assessment of relationships among and within Helichrysum Mill. (Asteraceae) species by using ISSR markers and morphological traits

Abstract

This study conducted to determine relationship among and within Iranian Helichrysum species (Asteraceae). In this study based on ISSR markers, the highest percentage of ISSR loci polymorphism (54.7%) occurred in H. armenium. The highest gene diversity over loci (1.224), Shannon’s Information Index (0.224%) and Expected Heterozygosity (0.142%) occurred in H. armenium (0.18) and the lowest of these parameters (0%) were observed in H. araxinum, H. graveolens, H. persicum and H. psychrophilum. The highest genetic similarity occurred between H. armenium and H. rubicundum (0.989), while the lowest was between H. polyphyllum and H. graveolens (0.213). The analysis of molecular variance (AMOVA), showed significant genetic variation among (24%) and within (76%) species. In morphological analysis traits such as indumentum, resting bud, achene length, achenial papillae, dimension of receptacle and form and apex of phyllaries were main diagnostic features. Results obtained from the morphological cluster were greatly consistent with the molecular data, to elucidating taxonomic relationships, as well as both attributed the higher diversity in H. armenium and H. rubicundum in comparison with other species and also indicated that H. persicum is a member of H. oocephalum species. Totally we confirmed the presence of 18 species in Iran.

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Biogas Production Potential from Animal Manure in Samsun Province of Turkey

Abstract

The aim of this study was to determine biogas amount and the energy value produced from animal manure in Samsun province, Turkey. For this purpose, biogas potential was calculated considering the number of cattle, buffalo and laying hens in the province. Samsun has a total of about 300 thousand cattle, 18 thousand buffalo, and 1.4 million laying hens. From these animals in the province, 2.95 million t of cattle manure, 178 thousand t of buffalo manure, and 40 thousand t of laying hens manure, including the total of 3.2 Mt of manure per year is obtained. Annually, 53.6 Mm3 of biogas can be produced from the usable amount of this manure. The heating value of biogas produced from this manure is about 1.22 PJ. The electricity production from this biogas is about 135 GWhel. These values can provide 4.96% of Samsun’s annual electrical energy consumption (2720 GWhel). The distribution of these calculated amounts by districts was mapped. When districts are listed according to the biogas production amount, the top seven Samsun districts are Bafra (16.2%), Center (16.0%), Carsamba (12.1%), Vezirkopru (11.0%), Terme (7.6%), Alacam (7.4%) and Havza (7.0%).

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Can trail characteristics influence visitor numbers in natural protected areas? A quantitative approach to trail choice assessment

Abstract

Planning for recreational activities in protected areas involves an understanding of multiple and complex factors. Trails constitute the main recreation facility in protected areas. They are an important and common infrastructure that concentrates visitor movement. Their sustainable planning and management requires an understanding of how the visitors made their selection. The aim of this study was to identify the effect of trail attributes on visitor numbers in the Krkonoše Mountains National Park in the Czech Republic. The methods used in this study present an analytical approach involving geographic information system analysis, field monitoring and data analyses using generalised linear models. The results showed the preferential tendencies among visitors to certain trail attributes. Marginal significance and a rather strong variability in preferences (over 10%) were identified for five trail characteristics: the amount of local attractions; diversity of land cover types; dominant land cover along a trail; soil erosion; and the type of trail surface. In our study, we illustrate an analytical framework for the assessment of trail characteristics that can help guide trail analyses and management efforts. On the other hand, our findings raise new research questions and point to the requirements for further research in order to better understand how environmental attributes influence visitor choice and to use this knowledge for trail planning and management.

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The Centennial of Mendel University in Brno and its Faculty of Agrisciences (Editorial)

Abstract

The paper describes the development of Mendel University in Brno and its Faculty of AgriSciences during last 100 years. It shows the present state of the University and Faculty, including facilities used for educational, scientific and other activities. The journal European Countryside owned by the University has been established 10 years ago. It is a highly cited per review periodical in the field of rural development. This special number gave the opportunity to the members of the Advisory Board to co-celebrate the anniversary by means of their own topic related scientific article.

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