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Open access

Francesco Poggi

Abstract

The aim of this article is to examine the interactions among main cities and the rural communities subordinate to them in central Italy during Late Middle Age. Premise of my work is the refusal of the assumption that cities and towns interacted between them as a whole. I choose Orvieto and its subordinate town of Bagnoregio in 1303 and 1304 as case study to enlighten that parties and faction based in the city and in the town interacted in ways that it is impossible to reduce to the dichotomy master- servant: this links as a whole shaped the dialogue between the city and its subordinates.

Open access

Ali Najafifar, Jaafar Hosseinzadeh and Abdolali Karamshahi

Abstract

Soil moisture plays a key role in the ecological capability of arid and semi-arid woodland. Reducing soil moisture due to frequent droughts causes pest prevalence and disease outbreak and the consequence of forest dieback. On the other hand, soil moisture is strongly correlated with the amount of radiation received on the Earth's surface. The sun's radiation is traditionally described often by aspect and sometimes by toposhape. The use of the hillshade map for estimating solar radiation is possible through developing GIS. The present study aimed to compare the relationship and the ability of these indices to describe the phenomenon of arid and semi-arid woodland decline better and more accurately in a case study in the west of Iran. To this aim, the aspect and toposhape layers were generated in 5 and 12 classes, respectively. Then, the hillshade map in range of 0-255 was made during the peak of summer heat. The comparison of the dieback ratio in the three characteristic histograms showed that the shade index, unlike the other two indicators, had a significant effect on forest drought (R2=0.91 for linear equation and R2=0.94 for quadratic equation). The results indicated that the application of hillshade in describing and analysing ecological processes by relying on soil moisture such as woodland dieback is superior to the other two indicators. It is suggested that this index be used to obtain a risk model to predict woodlands dieback which are under the pressure of frequent droughts due to climate change or other mortal factors.

Open access

Sheriza Mohd Razali, Ahmad Ainuddin Nuruddin and Marryanna Lion

Abstract

Mangroves critically require conservation activity due to human encroachment and environmental unsustainability. The forests must be conserving through monitoring activities with an application of remote sensing satellites. Recent high-resolution multispectral satellite was used to produce Normalized Difference Vegetation Index (NDVI) and Tasselled Cap transformation (TC) indices mapping for the area. Satellite Pour l’Observation de la Terre (SPOT) SPOT-6 was employed for ground truthing. The area was only a part of mangrove forest area of Tanjung Piai which estimated about 106 ha. Although, the relationship between the spectral indices and dendrometry parameters was weak, we found a very significant between NDVI (mean) and stem density (y=10.529x + 12.773) with R2=0.1579. The sites with NDVI calculated varied from 0.10 to 0.26 (P1 and P2), under the environmental stress due to sand deposition found was regard as unhealthy vegetation areas. Whereas, site P5 with NDVI (mean) 0.67 is due to far distance from risk wave’s zone, therefore having young/growing trees with large lush green cover was regard as healthy vegetation area. High greenness indicated in TC means, the bands respond to a combination of high absorption of chlorophyll in the visible bands and the high reflectance of leaf structures in the near-infrared band, which is characteristic of healthy green vegetation. Overall, our study showed our tested WV-2 image combined with ground data provided valuable information of mangrove health assessment for Tanjung Piai, Johor, Malay Peninsula.

Open access

Woon Hang Lee, Saiful Arif Abdullah and Shukor Bin Md Nor

Abstract

Unabated land use changes in developing countries have imperilled the urban ecosystem resilience. An urban protected area is one of the critical systems to absorb disturbance regimes in the metropolitan area, but it is increasingly pressured by urbanization. Therefore, assessing their land use and landscape pattern changes are pivotal to identify the conservation capacity. We developed land use maps for Klang Gate, Bukit Kutu, and Sungai Dusun wildlife reserves to assess their spatial and temporal land use changes between 1988 and 2012. The degree of fragmentation, the intensity of human impact and structural connectedness for these wildlife reserves were also quantified. The findings revealed that Klang Gate which located adjacent to the highly urbanizing area experienced a very significant loss of forest while built-up area and commercial agriculture gradually encroached into the reserve. It also has a higher degree of fragmentation and human impact than the other two reserves. Human impact inside of Klang Gate was concomitant to the outside. However, Bukit Kutu almost undisturbed and Sungai Dusun was slightly intruded by commercial agriculture. The results help different stakeholders, such as managing authorities and policy planners to strategize new land use planning that utilize limited land-based resources for future economic and social development. As the findings showed that urban protected areas alone are not sufficient in maintaining the urban ecosystem; therefore new conservation planning that integrates other urban green spaces at their surrounding is critical to ameliorating the conservation on a long-term basis.

Open access

Praveen Kumar Rai, Prafull Singh, Varun Narayan Mishra, Anisha Singh, Bhartendu Sajan and Arjun Pratap Shahi

Abstract

An assessment of Varuna river basin of India was performed to study the various drainage parameters in GIS platform. The delineation of drainage network is possible either physically from topographic sheets or with the help data of Digital Elevation Model (DEM) by methods for calculation techniques. Extraction of the basin and sub-basins, stream network has been produced to evaluate the drainage characteristics in the study zone. The entire Varuna river basin has been subdivided into 3 sub-watersheds and 41 morphometric parameters have been computed under four broad categories i.e. drainage network, basin geometry, drainage texture, and relief characteristics. The morphometric analysis has been performed and different parameters have been correlated with each other to understand their underlying connection and their role over the basin hydro geomorphology. The study discloses different types of morphometric analysis and how they influence the soil and topography of the basin. The investigation and estimation of basin morphometry and relief parameters in GIS will be of massive utility in catchment area advancement, understanding the watershed for natural resource evaluation, planning and administration at any scale. The outcomes thus generated equip us with significant knowledge and may also provide an input that are essential in decision making for watershed planning and drainage development of the watershed.

Open access

Katarína Demková, Martin Hais and Magda Edwards-Jonášová

Abstract

Landscape structure is determined by human activities and natural processes. Despite both influences are described in many studies, there remains still question, how the landscape structure reflects the individual socio-economic predictors. To answer this question we compared landscape structure, with emphasis on non-forest woody vegetation, of two states, however, with common socio-economic and political history. Non-forest woody vegetation represents characteristic feature in rural landscape, which increases water retention, biodiversity and bio-migration using green structures. In our study we supposed, that non-forest woody vegetation will have high sensitivity to societal changes and nature conservation measures. On an example of border region in former Czechoslovakia we compared three classes of non-forest woody vegetation (solitaires, patches and linear elements) in three time horizons (1950, 1986, 2011). The most significant differences in spatial structure of non-forest woody vegetation between countries were in the number and area of solitaires, which decreased during the entire period. However, the largest solitaire decrease was in 1950-1986, mainly in correspondence with socialist collective farming. Moreover, the decrease was higher in the Slovak part compared to the Czech part. The primary reason for this was the removal of non-forest woody vegetation on one side and the joining crowns into bigger patches on the other side. The current trend of increasing area of patch and linear elements is related to natural succession. We assume that the main drivers of different development in non-forest woody vegetation in the border region after the split of Czechoslovakia were different management measures applied in nature and landscape conservation and social development.

Open access

Michael Polczynski and Mark Polczynski

Abstract

In 1630, Guillaume Le Vasseur, sieur de Beauplan, travelled to the lands of Poland-Lithuania to begin a seventeen-year military career in the Crown army. The purpose of the Beauplan’s Ukraine (BU) project is to provide a set of open access, georeferenced databases for the populated places, rivers, river fords, river rapids, islands, forests, mountains, valleys, and travel paths that are shown on a selection of maps created by Beauplan. The purpose of this document is to describe how these databases and related materials can be accessed and applied by scholars, with the ultimate goal of this work being to convert the rich source of information provided by Beauplan’s maps into a viable instrument for the laboratory of the historian of south-eastern Europe in Early Modern times.

Open access

Andrzej Pytlik

Abstract

At present, the suspended monorail systems constitute a very common means of transportation in the Polish hard coal mines. The main advantages of the suspended monorail include the independence of the route from the working floor surface irregularities and the possibility to transport cargo of significant mass and size.

The masses and dimensions of machines and devices transported via monorail have increased considerably in recent times. This particularly concerns the transport of longwall system elements. In Poland, the maximum speed of suspended monorail travel is 2 m/s. Due to the fact that preparations are currently underway to increase the maximum speed above 2 m/s, it is necessary to inspect what influence it will have on work safety and mining support stability.

Current operational experience and tests have shown that dynamic loads induced by the suspended monorail transportation have a significant influence on the roadway support stability, working protection durability and on the monorail operators. This is particularly true during the emergency braking of a suspended monorail by means of a braking trolley, where the overloads reach 3g.

Bench tests of the selected steel arch and rock bolt support elements utilised in the Polish hard coal mines were conducted in order to determine the resistance of steel arch and rock bolt supports to static and dynamic loads.

The article presents the results of the tests conducted on a steel arch support in the form of the sliding joints of an ŁP/V29 yielding roadway support, which is commonly employed in the Polish hard coal mines. Tests of elements of the threaded bolts with trapezoidal threads over the entire rod length were conducted as well.

The conducted strength tests of steel arch and rock bolt support elements under static and dynamic loading have shown that dynamic loading has decisive influence on the support’s retaining of its stability. Support element stability decreases along with the increase of the impact velocity. This concerns both the steel arch support and the rock bolt support.

Open access

Alaa H. J. Al-Rkaby

Abstract

Waste material such as used tires is increasing every year, which poses environmental problems. However, such material has been used in several geotechnical applications as alternative lightweight backfill in highway embankments and/or behind retaining walls, providing environmental, economic and technical benefits. These applications require knowledge of engineering properties of soil-tire rubber mixtures. The present study aims to show the possibility of tire rubber usage in sand by evaluating the shear strength and deformability of sand mixed with granulated rubber, in weight percentages between 0 and 50%. The tire rubber content was found to influence the stress-strain and deformation behavior of the mixtures. The shear strength of sand mixed with 10% or 20% tire rubber was higher than that measured for sand only. However, the trend for TRC = 30–50% was different. Samples with a rubber content of 30-50% exhibited a rapid decrease in the stress ratio compared with that of sand. The major principal strain at maximum stress ratio was found to increase with increasing tire rubber content. However, it was observed that the lateral strains (minor and intermediate principal strains) of samples reduced significantly with the addition of tire rubber to the sand.

Open access

Wiesław Ostrowski, Dariusz Dukaczewski and Anna Markowska

Abstract

The authors present a comparative analysis of presentation of build-up areas with conventional symbols on 60 civil European topographic maps. The above-mentioned maps are in different scales, from 1:10,000 to 1:100,000, and have been published in nineteen European countries and the autonomous community of Catalonia. The analysis has proved that the scope of characteristics of build-up areas presented on the analysed maps was very diverse, from qualitative and quantitative point of view (e.g. there were between 2 and 25 different categories on 1:10,000 maps). The 1:10,000 and 1:50,000 maps generally contain more information on the characteristics of build-up areas than 1:25,000 maps. The characteristics themselves are also very diversified (e.g. only 6 of them appear on more than half of the analysed maps – most often churches).

Polish maps stand out due to the fact that they contain particularly rich and consistent representation of both physiognomic characteristics and general functional characteristics of buildings and build-up areas at all the analysed scales.