| 1. |
- Bou Kheir, Rania, et al.
(författare)
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Definition of landscape erosion units using a structural classification OASIS of Landsat TM satellite imageries, case study Lebanon.
- 2006
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Konferensbidrag (refereegranskat)abstract
- Soil erosion by water is a major cause of landscape degradation in semi-humid to semi-arid Mediterranean environments. Terrain particularly susceptible to the phenomenon witness a combination of erosive soil, unconsolidated rock type, steep slope, high rainfall intensity, active tectonic movement, rapid land use change and intense human interference. Current erosion models (e.g. USLE, RUSLE) are based on defining values to some of the factors described above followed by a plain multiplication between these parameters to assess erosion in tons/year. However the factors relative influence is uncertain and in addition, most of them have not been thoroughly validated. Instead a methodology is here proposed that involves the construction of landscape units and study their resistance to erosion through the analysis of satellite imageries and digital thematic maps. The structural classification system, OASIS (Organisation et Analyse de la Structure des Informations Spatialisées), is based on the identification of fuzzy groups defined spatially according to the neighbourhood context. These groups were derived from a Landsat TM (30*30 m) satellite image covering a representative region of Lebanon. Several fuzzy groups were distinguished related to bare soils (seven types), vegetated areas (four types) and urban zones, and distributed into 386 compacted polygons. Thematic erosion information that are added to these polygons are geological substrate, soil type, slope, drainage density, annual precipitation, and constructed information i.e. vegetation cover density, rock infiltration and movement, soil infiltration, soil water-retention capacity and soil erodibility. To report attribute information of all these maps on polygons deduced from the interpretation of satellite imageries and prevent error multiplication, three decision rules of visual interpretation were defined: (1) dominance rule – a given terrain polygon is characterized by the thematic unit that is dominant in the area; (2) unimodality rule – if, on a large terrain polygon, a bimodal population exists for a theme, it is divided into two new polygons; and (3) scarcity conservation rule – if, on a large terrain polygon, there is a theme occupying a small area that does not exist elsewhere, it is saved in a new polygon. This approach results in the division of the 955 km2 study area into 10 homogeneous, synchronized and well synthesized erosion units. A statistical validation (error matrices) conducted on the landscape map proves its efficiency in representing the real world, much better than going through an overlay (intersection) of GIS layers. The developed approach seems applicable to other areas of the country, thus constituting a tool for soil conservation planning and sustainable management.
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| 2. |
- Brogaard, Sara, et al.
(författare)
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Primary production of Inner Mongolia, China, between 1982 and 1999 estimated by a satellite data-driven light use efficiency model
- 2005
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Ingår i: Global and Planetary Change. - : Elsevier BV. - 1872-6364 .- 0921-8181. ; 45:4, s. 313-332
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Tidskriftsartikel (refereegranskat)abstract
- Declining biological production as a part of an ongoing land degradation process is considered a severe environmental problem in the dry northern and northwestern regions of China. The aim of this study is to develop and adapt a satellite data-driven gross primary production model called Lund University light use efficiency model (LULUE) to temperate conditions in order to map gross primary production (GPP) for the Grasslands of Inner Mongolia Autonomous Region (IMAR), China, from 1982 to 1999. The water stress factor included in the original model has been complemented with two temperature stress factors. In addition, algorithms that allocate the proportions of C3/C4 photosynthetic pathways used by plants and that compute temperature-based C3 maximum efficiency values have been incorporated in the model. The applied light use efficiency (LUE) model is using time series of the Normalized Difference Vegetation Index (NDVI), CLouds from AVHRR (CLAVR) from the 8-km resolution NOAA Pathfinder Land Data Set (PAL). Quasi-daily rainfall and monthly minimum and maximum temperatures, together with soil texture information, are used to compute water limitations to plant growth. The model treats bare soil evaporation and actual transpiration separately, a refinement that is more biophysically realistic, and leads to enhanced precision in our water stress term, especially across vegetation gradients. Based on ground measurements of net primary production (NPP) at one site, the LULUE reproduces the variability of primary production better than CENTURY or NDVI alone. Mean annual GPP between 1982 and 1999 range from about 100 g/m(2) in desert regions in the west to about 4000 g/m(2) in the northeast of IMAR, and the coefficient of variation for GPP is highest near the margins of the deserts in the west where rainfall is erratic. Linear trends fitted through the 18-year time series reveal that the western regions have encountered no change, while a large area in the center of the IMAR shows marked increases in GPP. In the northeast, negative trends in GPP are noted and coincide with rainfall trends. Though the high inter-annual variability in primary production undermines the identification of significant trends, we could not isolate any general decline in grassland primary production.
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| 3. |
- Lubida, Alex, et al.
(författare)
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Applying the theory of planned behavior to explain geospatial data sharing for urban planning and management : Cases from urban centers in Tanzania
- 2015
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Ingår i: African Geographical Review. - : Informa UK Limited. - 1937-6812 .- 2163-2642. ; 34:2, s. 165-181
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Tidskriftsartikel (refereegranskat)abstract
- This paper illustrates the potential use of the theory of planned behavior as a guiding framework for understanding intentions and behavior in geospatial data sharing in Tanzania. A structured questionnaire survey, was constructed and sent to local governments as well as academic and private organizations that are major producers and/or users of geodata. The questionnaire covered issues of how collection of geodata is financed, management of geospatial data, and compatibility of spatial data-sets. The theory was found to be generally effective in accounting for intentions to share geospatial data in Tanzania (p <.01). Results show potential for data sharing between local governments and other organizations in Tanzania, and it is suggested that creating awareness among spatial data stakeholders and the establishment of a spatial data infrastructure policy framework will speed up geospatial data sharing.
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| 4. |
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| 5. |
- Nardi, Maria Andrea, et al.
(författare)
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Environmental Change in Conflict and Post-conflict Northern Uganda: A Geographical Analysis to Understand Prospects for Sustainable Peace and Development in the Region
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Ingår i: The Journal of Environment & Development. - 1552-5465.
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Tidskriftsartikel (refereegranskat)abstract
- Armed conflicts are acknowledged for their effects on the environment, includingecosystem degradation and biodiversity loss, but also ecological restoration. Bothprocesses impact post-conflict opportunities for peace and development. The armed conflict in Northern Uganda (1986–2008) profoundly affected local communities and their natural environment. While some areas suffered environmental degradation others underwent ecological restoration. Understanding this historical pattern is crucial for post-conflict natural resource management and peace and development prospects. This article aims to analyse vegetation changes in Northern Uganda during and after the conflict, exploring potential drivers of such changes and their implications for sustainable peace and development. Utilising remote sensing analysis and literature review, we observe a post-conflict ‘greening’ trend alongside a more equal vegetation deterioration and restoration spatial distribution. We propose that if these trends are driven by agriculture expansion, the way this is organised and articulated with natural vegetation will be central for peace and development.
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| 6. |
- Nardi, Maria Andrea, et al.
(författare)
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Nature of Peace: An Interdisciplinary Enquiry into Research at the Intersection of Nature, Peace and Post-Conflict
- 2019
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The nexus between the environment, natural resources and (armed) violence has been researched since the end of the nineties, however major theoretical and empirical gaps still exists in research on the precise role of nature or the natural environment during post-conflict and/or peacebuilding, particularly in relation to those countries that have undergone internal armed conflict.This paper presents a state of the art in research conducted at the intersection of nature, peace and post-conflict. It is based on a systematic research review of more than a hundred articles published in English on conceptual and theoretical questions and case studies from all over the world.The aim here is to contribute to enhance the knowledge we have about the relevance of nature or natural environment in peace and post-conflict studies. We seek to do so by trying to answer the following questions:a. What are the main theoretical and empirical gaps in current research in the intersection of peace, post-conflict and nature?b. Is it necessary to develop alternative notions of nature and / or peace in order to expand the academic research field and the political possibilities of peace?The study presented here is the result of the interdisciplinary research project “The Nature of Peace: exploring links between the natural environment and peace in post-conflict societies”, supported by the Pufendorf Institute for Advanced Studies at Lund University, Sweden, between September 2017 and April 2018.
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| 7. |
- Olafsdottir, Rannveig, et al.
(författare)
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A GIS Approach to Evaluating Ecological Sensitivity for Tourism Development in Fragile Environments. A Case Study from SE Iceland
- 2009
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Ingår i: Scandinavian Journal of Hospitality and Tourism. - : Informa UK Limited. - 1502-2250 .- 1502-2269. ; 9:1, s. 22-38
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Tidskriftsartikel (refereegranskat)abstract
- Expansion of tourism in the northern periphery regions provides innovative resources for an economic boost to many of the peripheral communities. The northern ecosystems are however extremely vulnerable. It is therefore of vital importance for such communities to plan the growth of tourism along sustainable lines in order to secure long-term economic benefit from tourism. Geographical Information Systems (GIS) can handle multiple spatial criteria and provide a tool for the allocation of resources between conflicting demands and aid decision-makers in planning. Despite increased use of GIS in environmental planning and management, the application of GIS to tourism planning is still limited. This study aims to develop a methodology to generate a Tourism Decision Support System (TDSS) to aid planning of sustainable tourism. A GIS model was developed based on classification of identified impact factors and variables, as well as selected classification algorithms that were used to assess categories of ecological sensitivity that may aid decision makers in planning and managing sustainable tourism in sensitive areas that are facing the risk of being subjected to ecological degradation.
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| 8. |
- Ólafsdóttir, Rannveig, et al.
(författare)
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Assessing hiking trails condition in two popular tourist destinations in the Icelandic highlands
- 2013
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Ingår i: Journal of Outdoor Recreation and Tourism. - : Elsevier BV. - 2213-0780. ; 3-4, s. 57-67
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Tidskriftsartikel (refereegranskat)abstract
- Nature-based tourism in the fragile Arctic environments is emerging as a major environmental concern, mainly due to extreme seasonality in these locations, the lack of suitable infrastructures and planning, and its interference with fragile ecosystems. In Iceland tourism has increased exponentially during the past decades, causing more environmental impacts on the country's natural recourses. Hiking is one of the most popular tourist activities in Iceland, especially in the interior highlands. This study had two goals: to map the current status of hiking trail conditions in two popular tourist destinations of the southern highlands, Pórsmörk and Fjallabak Nature Reserve (FNR); and to examine the relationship between trail condition assessment and local physical properties, such as elevation, gradient, soil type, and vegetation cover, in GIS. The current status of the hiking trails is much worse in the Pórsmörk area, where over 30% of the trail system is classified as being in bad and very bad condition, compared to 12% for the FNR. Of the analyzed physical properties only elevation has a clear relationship with hiking trail condition in both study sites and gradient in the Pórsmörk area. Importantly, severe conditions never apply to a whole trail, suggesting that trail conditions are a function of trampling magnitude and local physical properties. Hence, when maintaining hiking trails in vulnerable environments, such as the Icelandic highlands, a holistic understanding of the environmental impact of trampling is critical. Management implications When nature-based tourism enters very fragile environments, good monitoring techniques become even more important. Such is the case on hiking trails in the highlands of Iceland, where the study produced the following findings: Monitoring the conditions of hiking trails is vital for understanding the major causes of trail degradation in the Icelandic highlands. Implementing a visual field assessment with a condition scale based on simplified classification system, a whole trail system can easily and cost-effectively be monitored and changes recorded. Visual interpretation of the spatial patterns of a trails' condition can further aid managers to identify problem areas and to avoid this type of area in future planning.During new trail design, steep slopes should be avoided as trampling easily intensifies solifluction and thus contributes to soil instability and soil erosion. In flat areas trails should be designed so hikers do not easily walk off the trails and thus increase the area of their impact.Inevitably, the number of users contributes the most to trail degradation. Therefore in the most vulnerable areas of the highlands the flow and number of tourists should be restricted.Gathering high resolution geographical data for use in Geographical Information Systems (GIS) are important in order to monitor and track changes of hiking trail conditions. The possibilities to analyze spatially distributed data and relationships between variables further provides better understanding of cause and effect regarding tourism impact in sensitive natural environments.
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| 9. |
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| 10. |
- Olafsdottir, Rannveig, et al.
(författare)
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How Wild is Iceland? Wilderness Quality with Respect to Nature-based Tourism
- 2011
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Ingår i: Tourism Geographies. - : Informa UK Limited. - 1461-6688 .- 1470-1340. ; 13:2, s. 280-298
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Tidskriftsartikel (refereegranskat)abstract
- The Icelandic highlands are one of the few places left in Europe where tourists can experience pristine wilderness. During the past decades the highlands have, however, witnessed a rapid expansion in natural resource exploitation. This study attempts to evaluate the pristine condition of Icelandic wilderness by testing different methods of identifying and analysing wilderness with respect to nature-based tourism. The wilderness areas were mapped with respect to proximity to anthropogenic structures (proximity analysis) as well as what is actually visible in the landscape in relation to topography (viewshed analysis). When analysed with respect to proximity, result maps indicate that wilderness covers a little less than 34 percent of Iceland. When assessed at a national scale, results from the viewshed analysis show similar results. However, evaluation of the two methods tested indicates that the viewshed analysis gives a more dynamic image of the Icelandic wilderness areas, whereas the proximity analysis simply highlights static buffer zones relative to the network of anthropogenic features. It is concluded that a viewshed analysis provides a more qualitative result regarding the Icelandic wilderness resource at a local scale with respect to nature-based tourism.
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