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The long-term cattle impact on soil methanotrophs was investigated at cattle overwintering area located at the ecofarm in the South Bohemia. Four sets of soil samples were sampled in spring and fall of 2009 and 2010. Differences in methanotrophic community structure among experimental sites and were investigated by DGGE and MISA. Real-Time PCR was used for estimation of quantity of Type I methanotrophs. The CARD-FISH method was used to estimate the percentage shared and cell counts of Type I and Type II methanotrophs among all prokaryotic cells. Substantial part of the thesis was focused on optimization of methods used.

Utah ranchers commonly face risks to their livelihoods. The objective of this work was to determine if ranchers could make profitable improvements to private land forage given the combined threat of low beef prices, drought, and possible loss of public grazing. We used linear programming (LINDO) to identify the most profitable solutions for private land investment with an 11-year simulation. Operations were divided into small, medium, and large size classes. Various forage improvements and public permits were options. Two phases of a beef price cycle (peak and trough) and 2 precipitation patterns (wet and drought) were combined as joint favorable or unfavorable scenarios. Simulations were run for each size class of operation under each scenario with a 0, 50, or 100% cut in public grazing. The analysis was based upon a partial ranch budget, namely, cattle and forage revenue less forage investment costs. Under the favorable scenario of adequate precipitation and higher beef prices, all operations followed similar patterns of increasing herd size, retaining calves for sale as yearlings, selling alfalfa hay and barley, and treating various forages for enhanced production. All operations exhibited a positive net present value (NPV) over the 11 years. Reduction in access to public permits, however, reduced NPV more for medium-size operations most dependent on public grazing. Under the unfavorable scenario, operation size affected response to combined effects of drought and low beef prices. Small and medium operations decreased brood herds while large operations tended to increase brood herds. Reductions in public grazing lowered NPV more for the small and medium operations compared to the large operations. Work revealed 3 thresholds that could limit profitability of forage investment. These included: (1) dependency on public grazing for> 15% of total annual forage; (2) operation size <2001 >acres; and (3) beef prices of Across all scenarios and operations it was generally profitable to improve 4 forage types that filled gaps at different seasons to the year: wet meadow, alfalfa hay, irrigated pasture, and crested wheatgrass. Irrigated pasture was most important when precipitation was high, illustrating risks of irrigation in this dry environment.

The experiments described in this thesis were designed to assess changes in pasture dynamics (biomass and species composition of pasture) of grazing land on the Southern Tablelands of ACT and NSW, after 16 combinations of rabbit control treatments had been applied. The rabbit control performed by CSIRO Division of Wildlife and Ecology consisted of all combinations of presence-absence of Poisoning (using sodium monofluoroacetate, 1080: POIS), Ripping (ripping warrens using a tractor fitted with ripping tynes: RIP), Fumigation (pressure fumigation using chloropicrin: FUM) and repeated follow-up fumigation (using phostoxin pellets one, six and eighteen months after completion of the initial treatment: ANN). The pasture was assessed before treatments were applied, and every six months after rabbit control treatments. Treatment combinations were assigned randomly in a 24 factorial design on a total of 32 sites. There was a significant increase of pasture biomass at the RIP+ANN treatment at post-treatment sample 5. The analysis of covariance did not detect any other significant increase or decrease of pasture biomass for any rabbit control treatment, at any posttreatment sample. A significant increase of grass species occurred for the treatments of POIS+RIP+FUM, POIS and RIP+ANN for the post-treatment samples of 1, 3 and 5 respectively. There was a significant increase of thistles at the rabbit control treatments of POIS+RIP+FUM+ANN (post-treatment sample 1), RIP, ANN, RIP+FUM, RIP+FUM+ANN and POIS+RIP+FUM+ANN (post-treatment sample 3) and RIP and FUM+ANN (post-treatment sample 5). A significant increase of weeds occurred at FUM (post-treatment sample 3) and at FUM+ANN (post-treatment sample 5). No significant changes in the amount of herbs or legumes was apparent for any rabbit control treatment or post-treatment sample. There were no significant decreases for any species group. Except for the significant results for post-treatment sample 1, all significant increases of biomass for any species group occurred during spring (post-treatment sample 3 and 5) which suggests a growth phase during spring then subsequent dieback (particularly for thistles and weeds), as any change was not detected in the following autumn sample. No strong trend is evident for any particular rabbit control treatments, or any combination of treatments. Analysis of covariance revealed that the rabbit control treatment of RIP+ANN showed significant increases in both total biomass of pasture and grass biomass during post-treatment sample 5. This treatment reduced the number of active entrances the most. Significant positive correlations were found between pasture biomass (total) with grass, herb, legume, thistle and weed species groups. Significant negative correlations between grass biomass and the number of active entrances were found when the rabbit control had been highly effective in reducing the number of active entrances. When rabbit control had not been very successful, there was a significant positive but low correlation with the number of active entrances. There was no significant relationship between the number of active entrances with the weight of rabbit dung pellets. It is reasoned that they are different measures of rabbit abundance. More rabbit dung pellets were found closer to the warren than further away from the warren, but there was no correlation between rabbit dung and pasture biomass. Rainfall was above average for most of the experiment, biomass increased accordingly, and rabbit control was highly successful. The resulting changes in the pasture were difficult to detect, although some increases in species composition groups occurred. It is reasoned that the changes observed are partly attributable to seasonal conditions, and to high rainfall. Grazing by domestic animals, sheep and cattle, had been found to be consistent throughout the experiment.

Landwirtschaftliche Expansion und Intensivierung treiben die Umwandlung natürlicher Ökosysteme weltweit. Bis heute ist unklar, inwieweit politische Maßnahmen negative Folgen für die Umwelt minimieren können. Die Kombination mit Szenarien-Analysen kann ein Rahmen zur Unterstützung von Planungsprozessen schaffen, um potentielle Auswirkungen von politischen Maßnahmen zu erforschen. Das Ziel dieser Dissertation war es, die Triebkräfte der Veränderung von Argentiniens Agrarlandschaften zu verstehen, potentielle zukünftige Landnutzungsveränderungen zu analysieren und den Einfluss ökonomischer und naturschutzbezogener politischer Maßnahmen auf diese zu erfassen. Im ersten Teil der Dissertation wurden die Triebkräfte landwirtschaftlichen Landnutzungswandels mittels eines Nettoertrags-Modells ermittelt. Danach wurde der Einfluss von ökonomischen und naturschutzbezogenen Maßnahmen auf zukünftige Landnutzungsveränderungen sowie auf die Konnektivität von Waldgebieten mit Hilfe von Landnutzungs-Szenarien analysiert. Die Ergebnisse zeigen, dass landwirtschaftliche Intensivierung von ökonomischen Maßnahmen getrieben ist, während landwirtschaftliche Expansion durch naturräumliche Eigenschaften und Zonierungsprogramme jenseits der Profitmaximierung determiniert wird. Politische Maßnahmen mögen einen geringeren Einfluss auf Landnutzungswandel haben als bisher erwartet. Die Entwicklung von Agrarland konzentriert sich auf Gebiete mit hoher Priorität für den Umweltschutz. Zonierungsprogramme wie das Argentinische Waldgesetz stellen wirkungsvolle Maßnahmen dar, um umweltschädigenden Entwicklungen vorzubeugen. Die Erkenntnisse zeigen, dass Naturschutz nicht zwingend im Konflikt mit ökonomischer Entwicklung steht, denn mittels Landschaftsplanung kann die Konnektivität von Waldgebieten auch unter gleichbleibenden Abholzungsraten bewahrt werden. Die Dissertation zeigt den Mehrwert von a-priori Evaluierungen der potentiellen Einflüsse von Maßnahmen auf Landnutzungswandel. / Agricultural expansion and intensification drive the conversion of natural areas worldwide. Yet, it is not clear where and how much production would need to expand and intensify to meet future demands and how policies may help minimizing environmental trade-offs. Particularly the latter requires an understanding of the underlying forces that drive agricultural land-use changes. This offers a framework for planners and decision makers to explore potential impacts from policies, especially in very dynamic regions. Argentina, where agricultural expansion and intensification result in dramatic conversions of natural areas, is a good example of a dynamic human-environment system. The goal of this thesis was to understand the drivers of agricultural land-use change and to explore future trajectories of land-use change, and how economic and conservation policies may impact them. This thesis examines drivers of agricultural land-use changes using a net returns model of agricultural production. Then, it evaluates the effects of economic and conservation policies on future land-use changes and on the connectivity of forests by developing scenarios of future land-use change. Results highlight that agricultural intensification in Argentina is driven by economic interventions, whereas agricultural expansion primarily responds to environmental characteristics and zonation programs. Economic policies may have less power in governing land use changes than previously thought, as results suggest that there are other factors, than profit maximization, influencing land conversions. Future agricultural development would occur in priority areas for conservation in Argentina, but zonation policies, such as the Forest Law, appear to be powerful in limiting potential environmental trade-offs. Conservation planning does not necessarily need to conflict with economic development, since under similar deforestation rates; landscape planning can preserve forest connectivity in the Chaco.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Júlio de Castilhos City has undergone significant transformations in its rural space last decades. It has happened because of large lands retraction and extensive cattle ranching in favour of Soya new agriculture. The partial fragmentation of cattle breeding and its reorganization has occurred in three main forms: land rent, land sell and expropriation when non-productive land. It was carried out by Instituto Nacional de Colonização e Reforma Agrária (INCRA) because they were not taking their social function. The rural settlements made possible the introduction and the development of family farm in Júlio de Castilhos City and consequently the diversification of agricultural production. This research aimed at understanding the processes held responsible for the dynamics of Júlio de Castilhos rural space and its resulting conflits from 1960 to 2007. Moreover, it was analyzed productive, landing and socioeconomic transformations responsible for the formation of rural lands. The methodology is analytical and descriptive, based on field researches, through observation and interviews with farmers, landowners and other qualified informants. / O município de Júlio de Castilhos sofreu transformações significativas em seu espaço rural nas últimas décadas. Isso ocorreu devido à retração do latifúndio, domínio da pecuária extensiva, em favor da agricultura moderna da soja. A fragmentação parcial dos criatórios de gado e sua reestruturação ocorreram através de três formas predominantes: o arrendamento, a venda das propriedades e a desapropriação das terras improdutivas, realizada pelo Instituto Nacional de Colonização e Reforma Agrária INCRA, pois não estavam exercendo sua função social. Os assentamentos rurais possibilitaram a introdução e o desenvolvimento da agricultura familiar no Município e a conseqüente a diversificação da produção agrícola. Compreender os processos responsáveis pela dinâmica do espaço rural do Município e os conflitos decorrentes, no período entre 1960 a 2007, analisando as transformações produtivas, fundiárias e socioeconômicas responsáveis pela formação dos territórios rurais constituem os objetivos desta pesquisa. A metodologia é analítica-descritiva, fundamentada em trabalhos de campo, através de observações e entrevistas com os agricultores e proprietários rurais, além de outros informantes qualificados.

The aim of this thesis is to compare the National Footprint Accounts of the Czech Republic in the section of cropland and grazing land for the year 2007 based on globally available data and data available in the Czech Republic, and also to compare these National Footprint Accounts of the Czech Republic based on nationally available data from the years 2007 and 2013. This thesis used the method of calculation of the National Footprint Accounts developed by Global Footprint Network. The ecological footprint of cropland of the Czech Republic is lower according to national data compared to global data while the ecological footprint of grazing land is higher. According to national data, the ecological footprint of both cropland and grazing land of the Czech Republic was lower in 2013 compared to 2007. This work gives an opportunity to compare the calculation of the ecological footprint and biocapacity of cropland and grazing land based on different data sources and to compare the results based on data from 2007 and 2013. Powered by TCPDF (www.tcpdf.org)

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