1,011 research outputs found

    Contribution towards understanding the categorisation of landforms.

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    Dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Science in Geospatial Technologies.Categorisation in the geographic domain, including landform categorisation, is more subject to influence by cultural, linguistic, environmental and individual factors, than other domains. The study presented in this dissertation investigates the influence of landscape variation on the landform categories used by non-experts. Video-elicitation methods were used in interviews with inhabitants of two distinct landscape types, in Portugal. One study site was mountainous and topographically varied, while the other consisted of more homogenous, gently undulating terrain. Interview responses indicated that participants used more landform terms in descriptions of familiar landscapes. Specific place recognition was another stimulant for an increase in landform categorisation detail. Additionally, the participant group from the more homogeneous landscape had a smaller landform vocabulary, and primarily used variations on a core set of landform terms to describe topographic eminences. The other group had a much larger and more varied vocabulary.(...

    Geomorphometric segmentation of complex slope elements for detailed digital soil mapping in southeast Brazil

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    Hillslope elements have considerable potential in predicting soil properties and types in the landscape, making them likely to be a useful basis for detailed soil mapping. The goal of this research was to apply a previously developed digital hillslope position (DHP) model, calibrate it as needed to a Brazilian landscape, and test its utility as a basis for identification of detailed soil map units. The study area covers 2500 ha and is located on the border between the municipalities of Piracicaba and Santa Bárbara d\u27Oeste, São Paulo state, Brazil. A digital elevation model, with spatial resolution of 5 m, was used to obtain slope gradient, profile curvature and relative elevation with different analysis scales. Hierarchical rules for these digital terrain derivatives were used to segment the landscape into hillslope positions. The user-calibrated hillslope position model was verified against local experience by identifying the hillslope position in the field and comparing it with the model classification using the Kappa statistic and a confusion matrix. Soil samples were collected across multiple hillslopes with different lithologies. The samples were analyzed for chemical composition and soil particle size separates. The measured soil properties were assessed for statistical significance by variance analysis among hillslope position, parent material, and the interaction between the two. Student\u27s t-tests were performed iteratively across each hillslope position within a given parent material to identify specifically which soil properties were significantly different among the hillslope position map units. Variance analysis of soil samples located within the respective parent material map units identified significant differences for all soil properties measured, but only for some soil properties when categorized by DHP. Focusing on the parent material with a sufficient quantity of samples, there was always at least one hillslope position that was significantly different from the others for each soil property. Because each of these map units presented a significant difference in at least one soil property, they are useful for detailed soil mapping

    ‘This is not the jungle, this is my barbecho’ : semantics of ethnoecological landscape categories in the Bolivian Amazon

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    This work was supported from the ‘Forschungskredit’ by the University of Zurich [grant number FK-13-104]; Hans Vontobel Foundation; Maya Behn-Eschenburg Foundation; Ormella Foundation; and Parrotia Foundation.Peer reviewedPublisher PD

    Geomorphic Control on Soil Erosion – a Case Study in the Subarnarekha Basin, India

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    Geomorphology depicts the qualitative and quantitative characteristics of both terrain and landscape features combined with the processes responsible for its evolution. Soil erosion by water involves processes, which removes soil particles and organic matter from the upper sheet of the soil surface, and then transports the eroded material to distant location under the action of water. Very few studies have been conducted on the nature and dynamics of soil erosion in the different geomorphologic features. In the present investigation, an attempt has been made to assess the control of geomorphologic features on the soil loss. Universal Soil Loss Equation (USLE) was used to determine soil loss from the various geomorphological landforms. Principal component analysis (PCA) was implemented on the USLE parameters to determine the degree of association between the individual principal components and the USLE-derived soil loss. Results obtained from the investigation signify the influence of the various landforms on soil erosion. PC5 is found to be significantly correlated with the USLE-derived soil loss. The results ascertained significant association between the soil loss and geomorphological landforms, and therefore, suitable strategies can be implemented to alleviate soil loss in the individual landforms

    Inventory and Characterization of the Riparian Zone of the Current and Jacks Fork Rivers

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    The ecological, recreational, and economic value of the 134 mile (216 km) riparian corridor within the Ozark National Scenic Riverways (ONSR) is of great interest to land managers and conservationists. Recent interest in applying ecosystem management to forest systems has necessitated a fresh look at the tools and methods in use to assess existing patterns of plant community structure and diversity. The purpose and objective of the study described in this report was to initiate a series of vegetation studies that could be integrated with existing research and management infonnation on the riparian vegetation in the ONSR. Defining the compositional and spatial attributes of the riparian corridor were at the core of our research efforts. We used multivariate analysis and ordination techniques to characterize the composition and distribution of woody and herbaceous vegetation within the ONSR

    Semantic Representation of Context for Description of Named Rivers in a Terminological Knowledge Base

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    The description of named entities in terminological knowledge bases has never been addressed in any depth in terminology. Firm preconceptions, rooted in philosophy, about the only referential function of proper names have presumably led to disparage their inclusion in terminology resources, despite the relevance of named entities having been highlighted by prominent figures in the discipline of terminology. Scholars from different branches of linguistics depart from the conservative stance on proper names and have foregrounded the need for a novel approach, more linguistic than philosophical, to describing proper names. Therefore, this paper proposed a linguistic and terminological approach to the study of named entities when used in scientific discourse, with the purpose of representing them in EcoLexicon, an environmental knowledge base designed according to the premises of Frame-based Terminology. We focused more specifically on named rivers (or potamonyms) mentioned in a coastal engineering corpus. Inclusion of named entities in terminological knowledge bases requires analyzing the context that surrounds them in specialized texts because these contexts convey specialized knowledge about named entities. For the semantic representation of context, this paper thus analyzed the local syntactic and semantic contexts that surrounded potamonyms in coastal engineering texts and described the semantic annotation of the predicate-argument structure of sentences where a potamonym was mentioned. The semantic variables annotated were the following: (1) semantic category of the arguments; (2) semantic role of the arguments; (3) semantic relation between the arguments; and (4) lexical domain of the verbs. This method yielded valuable insight into the different semantic roles that named rivers played, the entities and processes that participated in the events educed by potamonyms through verbs, and how they all interacted. Furthermore, since arguments are specialized terms and verbs are relational constructs, the analysis of argument structure led to the construction of semantic networks that depicted specialized knowledge about named rivers. These conceptual networks were then used to craft the thematic description of potamonyms. Accordingly, the semantic network and the thematic description not only constituted the representation of a potamonym in EcoLexicon, but also allowed the geographic contextualization of specialized concepts in the terminological resource.PID2020-118369GB-I00 Spanish Ministry of Science and InnovationA-HUM-600-UGR20 Andalusian Ministry of EconomyFPU grant given by the Spanish Ministry of Educatio
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