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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.
1

Cultivation ridges in theory and practice : cultural ecological insights from Ireland /

Myers, Michael David, January 1998 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 1998. / Vita. Includes bibliographical references (leaves 535-571). Available also in a digital version from Dissertation Abstracts.
2

Landscape genetics of highly disturbed arable systems : insights gained from investigating a small mammal species

Wilson, Amanda January 2014 (has links)
A large proportion of the earth's surface is dedicated to food production, and agriculture is widely acknowledged to influence local biodiversity via habitat loss and degradation. Landscape genetics is an emerging field which can provide detailed understanding of how wildlife populations are influenced by landscape configuration and composition but the approach is yet to be fully integrated with agroecology. When addressing landscape genetics questions, small mammals may provide insight; they may act as model organisms, they are abundant, they are relatively easy to sample and they may have important ecological roles within arable ecosystems. This thesis merged the study of arable landscapes, landscape genetics and small mammals, to develop what is known about the landscape genetics of wild species in this dynamic habitat type. To decide upon a study organism, small mammals were surveyed at an example arable field site. Wood mice (Apodemus sylvaticus) were found to be the most abundant species and a microsatellite marker multiplex was developed for genotyping individuals. Two aspects of their landscape genetics in arable habitat were investigated. First, the possibility of temporal patterns in fine scale genetic structure of arable populations was explored, since this had not been investigated previously. Next, inter-population genetic differentiation was examined to determine whether arable habitat acted as a barrier to gene flow for this species. At the fine scale, three genetically distinct clusters of wood mice were identified and temporal variation in the spatial pattern was confirmed. There was no evidence that arable habitat acted as a barrier to gene flow for this species in comparison to populations in urban habitat, which showed significant differentiation. It is hoped that the landscape genetic insights provided by this thesis will encourage greater momentum for conducting landscape genetics studies in agricultural habitat.
3

Způsob hospodaření a složení plodinové struktury v historických souvislostech vývoje zájmového území Stropnice / Farming structure and composition of the crop in the historical context of the development of the area Stropnice

SALLAIOVÁ, Věra January 2010 (has links)
Historical data analysis are among the most fundamental methods of investigating the past in response to today, and comparing the results and planning for the future. Farming methods and crop composition structures are evolving according to the evolution of the state or country. Thanks to these findings, we can assess whether changes in how they influence management of negative or positive, and according to plan strategy for the next farming. This work was aimed at studying changes in the way of management in a historical context (since the 19th century to the present), and changes in crop structure. Size of area farmed varied depending on changes in the way management and the total revenues. During the world wars and after a general decline of crops. During collectivization and the emergence of new technologies has increased. After collectivization occurs decline and today yields are rising again. Increasing yields of grass land and pasture for the past few years, this research did not prove the contrary, it is apparent their decline and increase in other crops such as wheat, corn or potatoes.
4

Mapping Connectivity in the Swedish Agricultural Landscape

Franzén, William January 2020 (has links)
The changes that Swedish agriculture has undergone during the 20th century has resulted in strongly increased productivity, but at the cost of more intensive environmental impacts. One of these is loss of biodiversity, which is driven by, e.g., usage of pesticides and loss and fragmentation of habitats. A vital process for resilient ecosystems is the possibility for species to move between habitats, known as connectivity. One approach to increase connectivity is through strategic perennialization in the agricultural landscape. The aim of this thesis is to map structural connectivity in agricultural landscapes in two major agricultural regions in Sweden and explore options for enhancing connectivity by strategic perennialization. Objectives include the development of a model to map structural connectivity in the Swedish agricultural landscape, identify landscapes where conditions for biodiversity can be improved by strengthening the structural connectivity, and investigate the potential to improve the conditions for biodiversity by introducing perennial crops in the agricultural landscape. The resulting model is based on circuit theory using the software Circuitscape, in which land cover is treated as electric circuits, which are assigned resistance based on the permeability of different types of land cover. The resistance in the developed model is based partly on human impact and partly on structural differences from areas of high biological values, or value cores, between which connectivity is modelled, in terms of object height- and cover. Two agricultural production areas were investigated, Skåne plains and Västra Götaland plains, as well as a testing area in Skåne county. Connectivity maps were created and analysed, and potential areas for strategic perennialization were identified. A strategic perennialization scenario was also modelled in the testing area. Since the application of the model is structural connectivity, uncertainties regarding how well it relates to functional connectivity varies between species. Structural connectivity has nonetheless been shown to facilitate functional connectivity in several aspects. No significant difference in connectivity could be found in the trial area following the introduction of strategic perennialization, but this is most likely due to assumptions behind area selection. Therefore, other approaches for identifying promising locations for strategic perennialization, based on connectivity maps, need to be explored. / <p>2020-06-13</p>
5

Interakce člověka a krajiny: dopady společenskopolitických změn na zemědělství a krajinu Česka / Interaction of man and landscape: impacts of socio-political changes to the landscape and agriculture in Czechia

Zavadil, Tomáš January 2020 (has links)
This diploma thesis is an analysis of the influence of specific socio-political changes to the landscape and agriculture in Czechia. The chosen socio-political changes are the beginning of communist regime in 1948 and the transformation of the whole society after the end of communist regime in 1989. The main idea used in this thesis was the concept of driving forces and the other used concepts were social capital, agricultural diversification and intensification and extensification of the landscape. Detailed presentation of the influence of specific socio- political changes in agriculture and landscape was made by a case study in administrative region Tábor. The used concepts were described In the opening part as well as the main stages of development of agriculture and landscape in Czechia and in the model area. The main method used in the case study were semi-structured interviews with farmers, who were active in agriculture before 1948 and in the time of the research. According to the results of the research the influence of institutional driving forces significantly increased in comparison to the period before 1948. The results also showed to important role of non-productive functions of current agriculture. . Keywords: landscape, agriculture, driving forces, land use, intensification and...
6

Die reichstrukturierte Agrarlandschaft - ein unbeachteter Lebensraum für die gefährdete Europäische Wildkatze (Felis silvestris)

Jerosch, Saskia 20 July 2021 (has links)
Seit Ende des 20. Jahrhunderts wird eine Ausbreitung der solitär lebenden und streng geschützten Europäischen Wildkatze (Felis silvestris) registriert, die sich auch aus den bewaldeten Lebensräumen in die weitgehend offene Agrarlandschaft erstreckt. Kenntnisse über Lebensraumansprüche in diesen Landschaftsausschnitten liegen bisher für die Art nicht vor. Ziel der Studie ist es, erstmalig Daten zur Raumnutzung aus einem bisher kaum bekannten Lebensraum zu erfassen. Der ökologische Erkenntnisgewinn soll Empfehlungen für lebensraumverbessernde Maßnahmen in landwirtschaftlich geprägten Kulturlandschaften erbringen, die auch den Individuenaustausch zwischen Populationen der Art fördern. Die Ergebnisse der Telemetriestudie in der Goldenen Aue belegen eine regelmäßige Nutzung der reichstrukturierten Agrarlandschaft durch etablierte Individuen. Darüber hinaus wurde ein erfolgreiches Reproduktionsereignis dokumentiert. Das Geschlechterverhältnis und die Altersstruktur der erfassten Tiere (n = 11) waren ausgeglichen. Die Aktionsraumgrößen der Kater stimmten weitgehend mit dem in bewaldeten Lebensräumen ermittelten Raumanspruch männlicher Wildkatzen überein. Weibliche Wildkatzen nutzten in der reichstrukturierten Agrarlandschaft deutlich (um ca. 60 %) kleinere Streifgebiete als ihre Artgenossinnen in den bewaldeten Lebensräumen. Die Studie bestätigt die strenge Bindung der Wildkatze an deckungsbietende Strukturen. Die Analyse zur Habitatnutzung ergaben geschlechterspezifische Unterschiede: Während weibliche Wildkatzen in dem agrarisch dominierten Landschaftsausschnitt eher eine Bindung an flächige Strukturelemente, wie Feldgehölze- und kleine Waldinseln sowie aus der Nutzung genommene Streuobstwiesen zeigten, nutzten Kater hier lineare Elemente, wie strukturreiche Uferstreifen von Still-, und Fließgewässern sowie Weg- und Ackersäume intensiver. Die Daten belegen, dass der bisher unbeachtete Lebensraum – die reichstrukturierte Agrarlandschaft - durchaus alle wichtigen Lebensraumfunktionen für die Europäische Wildkatze erfüllen kann. Ein Grund für die geringe Größe der weiblichen Streifgebiete ist eine streng auf qualitativ hochwertige Habitatstrukturen begrenzte Lebensraumnutzung. Dabei scheint neben der Nahrungsverfügbarkeit ein ausreichend hohes Angebot deckungsbietender Strukturen in der Strauch- bis Baumklasse ausschlaggebend für eine Etablierung von Weibchen zu sein. In landwirtschaftlich geprägten Kulturlandschaften ist bei einer Mindestausstattung an deckungsbietenden Habitaten mit dem Vorkommen etablierter und reproduzierender Wildkatzen zu rechnen, insbesondere in der Peripherie besiedelter Waldlebensräume. Eine Prüfung der artenschutzrechtlichen Verträglichkeit im Rahmen der planungsrechtlichen Eingriffsregelung sollte zukünftig auch auf die angrenzenden Offenlandschaften (bis zu 4km) von bewaldeten Lebensräumen ausgeweitet werden. Als lebensraumverbessernde Maßnahme wird grundsätzlich eine Erhöhung der Strukturvielfalt in der Agrarlandschaft durch Schaffung oder/und Erhaltung von kleinräumigen Strukturen wie Feldgehölzen, Hecken und breiten Feld-Gewässerrainen mit aufkommender Sukzession empfohlen. Darüber hinaus gewährt dies einen Individuenaustausch zwischen räumlich getrennt voneinander liegenden (Teil)Populationen. / Since the end of the twentieth century, the solitary and strictly protected European wildcat (Felis silvestris) has spread from wooded habitats across the largely open agricultural landscape. Knowledge about habitat requirements in these landscape sections is not yet available for the species. The aim of the study is, for the first time, to generate space use data from so far less known habitat. The ecological gain of knowledge should provide recommendations for habitat-improving measures in agriculturally influenced cultural landscapes, which also promote the exchange of individuals between populations of the species. The results from the Golden Aue prove a regular use of a richly structured agricultural landscape by established individuals. In addition, a successful reproduction event was documented. The sex ratio and the age structure of the recorded animals (n = 11) were balanced. The home range sizes of males were largely consistent with the space requirement determined in wooded habitats. In a richly structured agricultural landscape, female animals clearly used (about 60 %) smaller home ranges than their conspecifics in the wooded habitats. The study confirms the strict binding of the wildcat to cover-providing structures. Gender differences were found: While females were more likely to be bound to areal structural elements such as copses, orchards and small forest islands, males used linear elements more extensively than females, such as structurally rich riparian strips of waterbodies and field margins in the agricultural landscape. The data show that the so far neglected habitat - the richly-structured agricultural landscape - can fulfill all important habitat functions for the European wildcat. One reason for the small female home ranges is probably an exclusive use of high-quality habitats, which in addition to the food availability also provide sufficient hiding places. In agricultural landscapes, assuming at least a minimum of cover habitats, the presence of established and reproducing wildcats can be expected, at least in the periphery of forest habitats. Increasing structural diversity in the agricultural landscape through the creation or / and preservation of small-scale structures such as copses, hedgerows and broad field-watercourses with emerging succession is recommended as habitat-improving measures. In addition, it provides for an exchange of individuals between spatially separated (sub) populations. In the future, an examination of the species protection compatibility in the context of the planning intervention regulations should also be extended to the adjacent open landscapes (up to 4 km) of forested habitats.

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