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Abstract

Iran, being located in arid and semi-arid regions, faces an increase in human demand for water, and the global climate change has led to the excessive use of groundwater. China, India and Iran were ranked from first to third, respectively, in excessive groundwater consumption in 2005. The effects of effective parameters on groundwater recharge such as precipitation, surface recharge and well water harvesting in the Karvan aquifer are assessed. Groundwater flow models have typically been and are being adopted since the beginning of this millennium to better manage groundwater resources. The decrease in groundwater level and the potential environmental hazards thereof have made the researchers here to apply the Groundwater Modelling System (GMS software) in 3D in the subject area. This modelling is calibrated and validated for 86 months at steady and unsteady states. In this study, six scenarios are defined as both an increase and a decrease of 30% in precipitation, both an increase and a decrease of 30% in surface recharge, an increase of 10% in well water harvesting and a decrease of 30% in well water harvesting. The best scenario is selected for the subject area water management.

Abstract

This article analyses the accuracy of the presentation of forests on Polish topographic maps. Four test polygons were selected, differing in forest coverage and spatial distribution of forest areas in order to improve the objectivity of the study. All the polygons were located in Roztocze. Four maps were tested: System 1965 (1:50 000), GUGIK80 (1:100 000), PUWG92 (1:10 000), and VMap L2 (1:50 000). The forest areas from the maps and aerial photographs were vectorised; then the photographs were converted into an orthophotomap that constituted the reference material. All materials were coherent in terms of content validity. After vectorising the range of the forests, sampling was conducted within the hexagonal fields. A comparison of the obtained values provided the basis for maps that presented the errors. The analysis permitted several conclusions to be drawn, generally stating that the credibility of maps within the scope of presenting forest areas depends on the scale and purpose of the map, and that any analyses based on these maps should assume that the results should have higher tolerance levels.

Abstract

The main issue of the study was to determine the importance of the climate factor for migration flows in Russia, as well as its impact on the intraregional level. The article also discusses the possible prospects that global warming may bring to Siberia. According to the results, the climate factor does not have a crucial influence on the decision to relocate in Russia, but it remains one of the most important, along with economic, social and political factors. At the regional level, the climate factor is less important than the agglomeration factor and others. The impact of global warming has now affected the overall increase in temperatures in Siberia, which is not yet sufficient to generate additional migration flows.

Abstract

The purpose of the article is to present the concept of using social media (SM) as data sources and communication tools, useful at the various stages of planning, implementing and monitoring the effects of tourism development on a local level. The first part discusses the stages of planning, then presents the characteristics of SM, along with a discussion of the issues presented in the literature to this date. The next part presents data sources and methods of research on SM and functions that they can perform in tourism. The concept presented, on the one hand, reviews the perspectives of practical use of SM as a communication tool and source of data and, on the other hand, the challenges related to the need to further deepen research on tourism planning methods that are adequate to the continuously changing environment.

Abstract

The Lagos Lagoon is under increased pressure from growth in human population, growing demands for natural resources, human activities, and socioeconomic factors. The degree of these activities and the impacts are directly proportional to urban expansion and growth. In the light of this situation, the objectives of this study were: (i) to estimate through satellite imagery analysis the extent of changes in the Lagos Lagoon environment for the periods 1984, 2002, 2013 and 2019 using Landsat-derived data on land cover, Land Surface Temperature (LST), Normalised Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI); and (ii) to evaluate the relationship between the derived data and determine their relative influence on the lagoon environment. The derived data were subjected to descriptive statistics, and relationships were explored using Pearson's correlation and regression analysis. The effect of land cover on LST was measured using the Contribution Index and a trend analysis was carried out. From the results, the mean LSTs for the four years were 22.68°C (1984), 24.34°C (2002), 26.46°C (2013) and 28.40°C (2019). Generally, the mean LSTs is in opposite trend with the mean NDVIs and EVIs as associated with their dominant land cover type. The strongest positive correlations were observed between NDVI and EVI while NDVI had the closest fit with LST in the regression. Built-up areas have the highest contributions to LST while vegetation had a cooling influence. The depletion in vegetative cover has compromised the biodiversity of this environment and efforts are required to reverse this trend.

Kurzfassung

Am Beispiel des politisch-planerischen Diskurses zu ehemaligen Planungen für ein großflächiges Einkaufszentrum in der Mainzer Innenstadt wird der potenzielle Mehrwert diskurs- und gouvernementalitätstheoretischer Zugänge zu raumbezogenen Fragestellungen erörtert. Insbesondere werden die diskursiven Mechanismen der Einschreibung einer unternehmerischen und depolitisierten Konzeption urbaner Räume in scheinbar neutrale und objektive Techniken raumbezogener Wirkungsanalysen herausgearbeitet. Die damit verbundene Sichtweise auf städtische Räume als Wettbewerbseinheiten, die durch raumwirtschaftliche Gesetzmäßigkeiten determiniert sind, wird jedoch gleichzeitig durch Gegendiskurse aufgebrochen, die das Bewahren ortsspezifisch gewachsener baulicher Strukturen zum Maßstab von Stadtentwicklungspolitik machen. Die Fallstudie verdeutlicht damit, wie mithilfe diskursanalytischer Zugänge die raumbezogenen Wissensordnungen freigelegt werden können, die die politischplanerische Steuerung gegenwärtiger Stadtentwicklungsprozesse anleiten.

Abstract

Dipole-dipole electrical resistivity tomographic method was applied to investigate the subsurface cavities at Staff Welfare Hospital & School Quetta. A total of 890-meter profile line was covered along five smaller profile lines and fracture zones with maximum 21 meters interval. The cavity system along profile line-1 and 2 was very restricted and had no direct impact on infrastructure while major cavity beneath the building was traced at profile line-3 and line-4 thus constituting a ~20m wide cavity system with 3-4 small interconnected cavities between depths of 7 to 21 meters. This system was also traced at profile line-4 at a depth of 10 meters having a reduced width of 10m. At profile line-5, a few other cavities were detected that proved imperceptible due to limitations in data acquisition. To conclude, the cavity systems traced in profile line-3 and profile line-4 were the most perilous ones and are commonly the foremost reason for building collapse.

Abstract

This study examined the contribution of wildlife tourism and conservation to employment generation and sustainable livelihoods of a community residing adjacent to the Kgalagadi Transfrontier Park, Southern Africa. Adopting a qualitative approach, semi-structured interviews were conducted with tourism stakeholders and focus group discussions with members of the community. The findings reveal wildlife tourism to have positively contributed towards providing diverse employment opportunities for the community. Additionally, the livelihood diversification strategies largely involved integrating the cultural and natural resources with the wilderness experience of the region. However, a major concern is the significant lack of linkages between wildlife tourism and the local economy of the community. While the study concludes wildlife tourism to be an important economic sector for the community, it recommends further integration of micro and small local businesses into wildlife tourism so as to enhance the contribution of the Park and wildlife tourism to community livelihoods.

Abstract

Caravan parks are a largely overlooked theme in tourism scholarship. In South Africa, as in several other countries, local governments assumed an historical role in the establishment of caravan parks. Municipal caravan parks are assets which could be leveraged for tourism growth and local development. The planning and management of caravan parks in South Africa can be understood as an element of asset management by local governments. It is shown that across most of South Africa municipal ownership of caravan parks is of declining significance as compared to the dominance of privately owned parks. The coastal province of the Western Cape is the biggest focus for caravanning and for the location of all caravan parks, including for the largest cluster of municipal owned caravan parks in South Africa. Research interviews were conducted with local stakeholders concerning contemporary planning and management of caravan parks. The results reveal that most local municipalities currently are struggling to manage appropriately and optimally maximise for local development the operations of municipal caravan parks. Many municipalities are considering different options for privatisation through selling off or leasing parks to private sector investors.