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Distribution of cold and temperate ice and water in glaciers at Nordenskiöld Land, Svalbard, according to data on ground-based radio-echo sounding

Abstract

The distribution of cold and temperate ice and water in polythermal glaciers is an important characteristic in studying their thermal regime, hydrology, and response to climate change. Data analysis of ground-based radio-echo sounding of 16 glaciers in Nordenskiöld Land in Spitsbergen shows that 5 of them are of cold type and 12 are of polythermal type. The mean thickness of cold and temperate ice in polythermal glaciers varies from 11±2 to 66±6 m and from 6±2 to 96±9 m, respectively, and their ratio varies from 0.30 to 5.31. The volume of temperate ice in polythermal glaciers varies from 0.0009 to 3.733 (±10%) km3. With water content of 2% in temperate ice in these glaciers they might contain in total up to ~93.5 × 106 m3 of liquid water. Radar data suggest the greater water content or greater size of water inclusions in near-bottom temperate ice.

Open access
Financing Low-income Housing in Bulawayo, Zimbabwe: Implications for the Right to the City and Inclusivity

Abstract

Accessing finances for housing has been a major problem for people on low-incomes and this has been weighing heavily on them as they try to access housing. Financial institutions in the city of Bulawayo are failing to come up with financial products that suit low-income clients. There are an estimated 110000 low-income residents among the estimated 250000 residents of Cowdray Park low-density residential area in Bulawayo. This has also affected their right to the city as they have been excluded from the housing delivery system. There are so many initiatives that have been available to those on a low-income but these initiatives have rarely benefited the urban poor of the city. This research has examined how the financial services that exist in the housing sector have been crafted to benefit the urban poor. The research employed a mixed methods approach to the inquiry, where a questionnaire was the main quantitative method used and in-depth interviews and observations were the qualitative methods that complemented it. The research found that there are various financial services that are available in Zimbabwe, but these financial facilities rarely help the urban poor. The majority of the poor have been managing without any financial support and this has been stalling their access to housing. Most housing products are fashioned along neo-liberal economic principles that have very little to offer the urban poor. This has therefore denied the urban poor in the city of Bulawayo their right to the city. Most cities in Zimbabwe are struggling to satisfy their housing demand as they have long housing waiting lists. Research therefore recommends the crafting of financial facilities that are best targeted on the urban poor, and are specially adapted to their financial conditions.

Open access
Fire occurrence and the current state of palaeofire reconstructions based on sedimentary charcoal from natural archives in Poland

Abstract

Due to rising temperatures worldwide many areas are threatened with increasing numbers of fire occurrence. Poland is among these areas and is projected to experience over the next century an increase in both heat stress and wildfire activity with the potential to turn its fire-resistant forests into fire-prone forests. This paper aims to provide an introduction to the conditions favourable to fire occurrence in Poland, summarising the research on sedimentary charcoal analysis and reviewing fire reconstructions based on natural archives from Poland. Here, natural wildfires occurred at the beginning of the Holocene but, due to changes in climate (wetter summers) and vegetation after 6550 BC, the main trigger of fire occurrence became human activity, mainly as a result of forest clearance for agrarian purposes. However, there is evidence that prolonged droughts also triggered wildfires. Over recent decades, according to existing data, arson (44.85%) and negligence (34.43%) have been the most common causes of fire occurrence in Poland.

Open access
Footprints of past geological events recorded in the petrography and mineralogy of rocks from the Krucze Skały excavation (Karkonosze Mountains, SW Poland)

Abstract

The Krucze Skały excavation is located within the Izera-Kowary Unit, which is a subdivision of the Karkonosze-Izera Massif. Traces of numerous geological events have previously been recognised and described in other locations within this unit. In this specific location only pegmatitic intrusions have been tested tested until now. This research considers the geological history recorded in the petrography and mineralogy of all remaining rocks. Samples collected along the excavation were analysed using a polarising microscope and the XRD method. During the examination, records of the magmatic genesis of these rocks protolith, as well as evidence of MP-LT and LP-HT metamorphism, metasomathosis and hydrothermal activity were found.

Open access
Formation of soil structure in long-term fertilised sandy soil: Role of the manganese oxides

Abstract

We investigated the role of Mn oxides on the soil structure (contents of dry and water-stable aggregates) of sandy soil under a controlled long-term fertilisation experiment. We examined two experiments: a 94-year-term experiment with: no fertilisers, NPK fertilisers, and CaNPK fertilisers; and a 25-year-term experiment that included: farmyard manure and no mineral fertilisation, farmyard manure + NPK fertilisers, and farmyard manure + CaNPK fertilisers. The results showed that in the 94-year-term trial, Mn oxides were increased in CaNPK treatment. In the 25-year-term experiment, the farmyard manure combined with NPK decreased total Mn and its oxides. In the 94-year-term experiment, the content of dry-sieved macro-aggregates (DSAma) and water-stable macro-aggregates increased due to fertilisation. The result of our study suggests that Mn oxides had positive effects mainly on higher size classes of DSAma and did not have any effect on water-stable aggregate contents.

Open access
Light pollution in the night sky of Toruń in the summer season

Abstract

The paper presents results of research on light pollution in the night sky of Toruń. A permanent network of measuring stations has been established in the city, consisting of 24 sites representing various types of land development and land cover: single-family housing, city centre, multi-family housing, areas overgrown with vegetation and open areas. Within this network, a repeatable direct measurement of the sky brightness using an SQM photometer was carried out over a period of three consecutive months in the summer season, i.e. from June to September 2017. The measurement sessions were conducted in similar weather and astronomical conditions. Based on the obtained data, a spatial distribution of light pollution was determined, ranges of values obtained during the measurements were provided, and the results were additionally referred to the distinguished land cover categories and land development types.

Open access
Luanda’s Slums: An overview based on poverty and gentrification

Abstract

Slum redevelopment is occurring at a rapid pace in many African cities. This paper examines the urban development of contemporary Luanda, the capital of Angola. Central to this examination is an analysis of the city’s slums according to Foucault’s concept of governmentality. The focus is on the chaotic urban development that has resulted from the civil war and on the effects of poverty and gentrification in many of Luanda’s slums. The policy of violence towards slum population adopted by the municipality appears to define a technology of domination, the subjection of the individual to the formation of the state. However, with the high earnings obtained from oil production, the country clearly has the resources needed to fund investments in electricity and utility systems. The continuing persistence of slums and a housing policy based on neglect signifies a form of governmentality, adopted as a means of government coercion and a way of dominating the poor population. The paper closes with a set of policy implications for action.

Open access
Methodological aspects of pH and EC measurements in geothermal water

Abstract

A proper methodology for collecting samples of geothermal water makes it possible not only to determine the hydrochemical characteristics of the water, but also to assess its temporal and spatial variability. The knowledge about the concentration of selected elements as well as the values of field measurements can help to indicate their impact on other environments and the processes that occur in a geothermal system. An important issue is the quality of the results obtained from in-situ measurements of unstable parameters, i.a. pH and electrical conductivity (EC). The results of measurements presented in the paper were completed with the use of three different devices in hot and cooled raw geothermal water (field test). The research was performed during two seasons of increased (winter) and lower (summer) exploitation of geothermal water. The percentage difference between EC at temperatures of 22°C and 75°C was 3.27%; however, for the pH the observed percentage difference was only 0.26%. An additional experiment was carried out on a laboratory scale to indicate the influence of temperature changes on pH and EC measurements.

Open access