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Number of results: 12
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Abstract

The abundance of water has certainly been a very important resource for the development of the Po Valley and has necessitated, more than once, interventions of regulation and drainage that have contributed strongly to imprint a particular conformation on the land. Already in Roman times there were numerous projects of canalisation and intense and diligent commitment to the maintenance of the canals, used for navigation, for irrigation and for the working of the mills. The need to control the excessive amount of water present was the beginning of the exploitation of this great font of richness that was constantly maintained in subsequent eras. In the early Middle Ages, despite the conditions of political instability and great economic and social difficulty, the function of the canals continued to be of great importance, also because the paths of river communication often substituted land roads, then left abandoned. After the 11th century A.D. the resumption of agricultural activity was conducive to the intense task of land reclamation of the Lombardian countryside and of commitment by the cities to amplify their waterways with the construction of new canals and the improvement of those already existing. The example given by Milan, a city lacking a natural river, that equipped itself with a dense network of canal, used in various ambits of the city life (defence, hygiene, agriculture, transport, milling systems) and for connections with the surrounding territory, can be considered as emblematic. In the surrounding countryside, the activity of the Cistercian monks of Chiaravalle represents one of the situations more indicative of how land reclamation and waterways contributed fundamentally to the organisation of the territory over the span of the ages.

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Giuliana Fantoni
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Abstract

The present work deals with population-based meiotic studies on eight species belonging to four genera of the family Commelinaceae from different regions of Kangra Valley which is well known for its rich floristic diversity. At the world level, different cytotypes for four species such as Commelina hasskarlii (2n = 22, 60), C. kurzii (2n = 60), Murdannia nudiflora (2n = 24) and M. spirata (2n = 24) have been recorded for the first time at various ploidy levels. Additionally, from India, the new chromosome count for Tradescantia pallida (2n = 24) has been reported at the tetraploid level. The course of meiosis has been found to be normal in all the populations of Commelina benghalensis, C. paludosa, Murdannia nudiflora and M. spirata while four species, Commelina hasskarlii, C. kurzii, Cyanotis cristata and Tradescantia pallida have shown a normal to abnormal meiotic course in different populations. These meiotic abnormalities have revealed a clear effect on the pollen size and pollen fertility.
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Harpreet Kaur
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Abstract

Australia to kraj bardzo bogaty w zasoby naturalne. Jest znaczącym eksporterem rud żelaza, boksytów, miedzi, złota, niklu oraz cynku. Kraj ten eksportuje także rudy uranu czy też węgiel kamienny i gaz ziemny. We własnym zakresie wykorzystuje również surowiec energetyczny, jakim jest węgiel brunatny. Podobnie jak w Polsce, służy on do produkcji energii elektrycznej zapewniając przy tym bezpieczeństwo energetyczne państwa. Pomimo znacznej odległości dzielącej te dwa kraje, mają one ze sobą wiele wspólnego. Zarówno Australia, jak i Polska opiera swoją elektroenergetykę w większości na rodzimych zasobach węgla kamiennego i brunatnego. Obydwa kraje osiągnęły także zbliżony poziom udziału OZE w miksie energetycznym. Podobny jest również poziom rocznego wydobycia węgla brunatnego. W artykule dokonano porównania górnictwa i energetyki opartej na węglu brunatnym w Australii i w Polsce. Analiza dotyczy ostatnich 20 lat, przy czym szczególną uwagę zwrócono na zmiany, jakie zaszły w tej branży po 2010 roku. Wskazano podobieństwa i różnice występujące w obydwu krajach w zakresie warunków geologiczno-górniczych wydobycia węgla brunatnego oraz jednostkowej efektywności i emisji dwutlenku węgla podczas produkcji energii elektrycznej. Opisano także stan i perspektywy rozwoju trzech kompleksów górniczo-energetycznych węgla brunatnego zlokalizowanych w Latrobe Valley w stanie Wiktoria w południowo-wschodniej Australii.
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Authors and Affiliations

Zbigniew Kasztelewicz
Mateusz Sikora
Maciej Zajączkowski
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Abstract

Palynological and archaeobotanical analyses were conducted on excavated sediments from Tse Dura, a Later Stone Age rock shelter in north-central Nigeria with the aim of reconstructing the environment conditions at the site within the last millennium. From 933 ± 29 BP to 802 ± 29 BP, the environment alternated between Guinea savanna with dry conditions, and secondary and riverine forests with humid conditions. During these periods of environmental fluctuations, the LSA populations engaged in the management of economic plants the most significant of which included Dioscorea spp. Pennisetum glaucum and Elaeis guineensis, and exploited wild plants such as Pavetta crassipes, Sarcocephalus latifolius and Lophira cf. lanceolata for dietary and ethnomedicinal purposes. Around 310 ± 30 BP cal, the environment became very wet after which it was succeeded by a drier period. It was during this period that Sorghum bicolor became prominent, and the environment attained its current status dominated by Guinea savanna elements and secondary forests.
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Orijemie Emuobosa Akpo
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Abstract

The aim of the article is to determine the main factors responsible for development of Podkarpackie Voivodeship in the last 15 years and to answer the question whether they were suffi ciently strong impulse to divert the region from its development model. The main method used for identifying the factors that determine the development of the region was individual, in-depth interviews with the main actors on the regional scene, supported by desk research analysis (of the voivodeship’s strategic and operational documents) and statistical data analysis (Central Statistical Office and Eurostat). The research highlights the importance of the immobile and intangible development factors – a high quality of strategic thinking of local and especially regional authorities and consistent implementation of development policies, a high level of social capital, extensive networks and the ability to co-operate – which have helped to eliminate the limitations resulting from the weakness of other factors.

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Authors and Affiliations

Anna Dąbrowska
Jacek Szlachta
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Abstract

The aim of the study was to assess the content of soluble forms of fertilizer nutrients (N, P, K) in the cultivated soil layer up to 20 cm deep from agricultural land in the river valley, and the concentration of these nutrients in the surface wa-ters of the Raszynka River.

In the years 2016–2017, the surface water samples from the Raszynka Rriver (17 points) and soil (19 points) were col-lected from agricultural areas near the Raszynka River.

The surface water samples were collected once a month during the March–October 2016–2017. The contents of nitro-gen (Ntot, NO3-N and NH4-N), phosphorus (Ptot, PO4-P), total organic carbon (TOC and K and Ca) in soils and in waters were determined in the sample solutions.

It was shown that river water was of low quality due to the high concentration of nitrogen and phosphorus and electri-cal conductivity (EC). The most polluted were the waters of the lower section of the river located in the vicinity of arable land and agricultural built-up areas. The soluble forms of nutrients content in the cultivated soil layer was varied dependingon the kind of nutrient, way of agricultural land use, and the term of soil sampling. The content of dissolved P forms in the soil was the highest in autumn on arable lands after harvesting of vegetables (GO-W: 10.24 mg Ptotꞏkg–1 in D.M.) and this component may migrate with surface runoff and increase the risk of surface water eutrophication.

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Authors and Affiliations

Irena Burzyńska
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Abstract

Various components of surface texture are identified, namely form, waviness and roughness. Separation of these components is done by digital filtering. Several problems exist during analysis of two-process surfaces. Therefore the Gaussian robust profile filtering technique was established and has been studied here. The computer generated 2D profiles and 3D surface topographies having triangular scratches as well as measured stratified surfaces were subjected to filtration. However even robust filter applications cause distortion of profiles having valleys wider than 100 μm. In order to minimize the distortion associated with wide and deep valleys, the robust filter should be modified. A special procedure was elaborated for minimizing distortion of roughness profiles caused by filtration. Application of this method to analyses of several profiles was presented. The difference between 1-D and 2-D filtering of surface topography using the same kind of filter was discussed. As a result we found that modification of a 2-D surface topography filter was not necessary.

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Authors and Affiliations

Paweł Pawlus
Paweł Dobrzański
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Abstract

The research was conducted at the Kwiatków site,1 in the Koło Basin (Central Poland). It included a fragment of a low terrace and the valley floor of the Warta river valley. The archaeological investigation documented over 100 wells that archaeological material indicates are associated with the Przeworsk culture. Geomorphological, lithological and geochemical studies were carried out at the archaeological sites and their surroundings. Selected for the presentation were two wells whose fillings were carefully tested and subjected to geochemical and lithological analyses. The wells showed a slightly different content of artifacts, as well as differences in their grain-size distributions, the structure of their filling deposits, and their geochemistry. This allows us to conclude that the two wells were used differently, but also probably about a different course for how each well was filled after the end of its operation.

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Authors and Affiliations

Magdalena Piotrowska
Daniel Okupny
Juliusz Twardy
Jacek Forysiak

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