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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Hybrid patches of commoning - Unpacking influences of the hydrosocial cycle on commoning in a downstream desert reclamation area : case study in Youssef El Seddik, Egypt / Hybrida utrymmen av kollektivt samarbete - Analys av influenser från den hydrosociala cykeln på kollektiva handlingar i ett nedströms nyodlat ökenområde : fallstudie i Youssef El Seddik, Egypten

Hellström, Benjamin, Sultan, Leila January 2020 (has links)
Water stress is increasing globally, especially affecting arid regions of the world such as Egypt. Due to challenges related to intensifying effects of climate change and a rapidly growing population, the levels of and access to water is a continuous area of concern for the country – making it important to analyze how these water issues are managed. This study connects the hydrosocial cycle and commoning frameworks in analyzing how water is managed in a downstream, desert reclamation area in Fayoum, Egypt – and how this management, or lack thereof, affects the livelihoods of the people living there. In doing so, we examine how possible commoning practices are influenced by factors related to the hydrosocial cycle. Fieldwork has been conducted for this case study by holding participatory workshops, semi-structured interviews, and observations. Our findings imply that the hydrosocial cycle has shaped the management of water in our studied site, which has in turn affected the commoning practices that take place there. The low water levels and the saline quality of the water is what has created the prevalent forms of commoning that can be seen in the community.  The presence of a local agricultural association has also influenced the commoning practices. The quality and levels of water in the area are in part managed by neighbors borrowing irrigation minutes from each other, and by collective olive harvest. To a lesser extent there are also instances of neighbors helping each other with agricultural work throughout the year, and sharing reservoirs. There are indications that these commoning practices play a part in sustaining livelihoods in the community. The commoning practices found in the studied site have emerged in a relatively new social context and can be characterized as context specific patches of commoning, occurring on the peripheries of hybrid institutions – that have largely been shaped by hydrosocial forces. As the hydrosocial cycle is ever-changing, these commoning practices will likely also come to change.
22

Drought analysis with reference to rain-fed maize for past and future climate conditions over the Luvuvhu River catchment in South Africa

Masupha, Elisa Teboho 02 1900 (has links)
Recurring drought conditions have always been an endemic feature of climate in South Africa, limiting maize development and production. However, recent projections of the future climate by the Intergovernmental Panel on Climate Change suggest that due to an increase of atmospheric greenhouse gases, the frequency and severity of droughts will increase in drought-prone areas, mostly in subtropical climates. This has raised major concern for the agricultural sector, particularly the vulnerable small-scale farmers who merely rely on rain for crop production. Farmers in the Luvuvhu River catchment are not an exception, as this area is considered economically poor, whereby a significant number of people are dependent on rain-fed farming for subsistence. This study was therefore conducted in order to improve agricultural productivity in the area and thus help in the development of measures to secure livelihoods of those vulnerable small-scale farmers. Two drought indices viz. Standardized Precipitation Evapotranspiration Index (SPEI) and Water Requirement Satisfaction Index (WRSI) were used to quantify drought. A 120-day maturing maize crop was considered and three consecutive planting dates were staggered based on the average start of the rainy season. Frequencies and probabilities during each growing stage of maize were calculated based on the results of the two indices. Temporal variations of drought severity from 1975 to 2015 were evaluated and trends were analyzed using the non-parametric Spearman’s Rank Correlation test at α (0.05) significance level. For assessing climate change impact on droughts, SPEI and WRSI were computed using an output from downscaled projections of CSIRO Mark3.5 under the SRES A2 emission scenario for the period 1980/81 – 2099/100. The frequency of drought was calculated and the difference of SPEI and WRSI means between future climate periods and the base period were assessed using the independent t-test at α (0.10) significance level in STATISTICA software. The study revealed that planting a 120-day maturing maize crop in December would pose a high risk of frequent severe-extreme droughts during the flowering to the grain-filling stage at Levubu, Lwamondo, Thohoyandou, and Tshiombo; while planting in October could place crops at a lower risk of reduced yield and even total crop failure. In contrast, stations located in the low-lying plains of the catchment (Punda Maria, Sigonde, and Pafuri) were exposed to frequent moderate droughts following planting in October, with favorable conditions noted following the December planting date. Further analysis on the performance of the crop under various drought conditions revealed that WRSI values corresponding to more intense drought conditions were detected during the December planting date for all stations. Moreover, at Punda Maria, Sigonde and Pafuri, it was observed that extreme drought (WRSI <50) occurred once in five seasons, regardless of the planting date. Temporal analysis on historical droughts in the area indicated that there had been eight agricultural seasons subjected to extreme widespread droughts resulting in total crop failure i.e. 1983/84, 1988/89, 1991/92, 1993/94, 2001/02, 2002/03, 2004/05 and 2014/15. Results of Spearman’s rank correlation test revealed weak increasing drought trends at Thohoyandou (ρ = of 0.5 for WRSI) and at Levubu and Lwamondo (ρ = of 0.4 for SPEI), with no significant trends at the other stations. The study further revealed that climate change would enhance the severity of drought across the catchment. This was statistically significant (at 10% significance level) for the near-future and intermediate-future climates, relative to the base period. Drought remains a threat to rain-fed maize production in the Luvuvhu River catchment area of South Africa. In order to mitigate the possible effects of droughts under climate change, optimal planting dates were recommended for each region. The use of seasonal forecasts during drought seasons would also be useful for local rain-fed maize growers especially in regions where moisture is available for a short period during the growing season. It was further recommended that the Government ensure proper support such as effective early warning systems and inputs to the farmers. Moreover, essential communication between scientists, decision makers, and the farmers can help in planning and decision making ahead of and during the occurrence of droughts. / Agriculture, Animal Health and Human Ecology / M. Sc. (Agriculture)

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