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1	COMPARING THE COMPOSITION OF SAPROXYLIC BEETLE FAUNA ON OLD HOLLOW OAKS BETWEEN TWO TIME PERIODS Kamboyi, Chipango January 2019 (has links) Oak habitats are rich in saproxylic species, but the habitat is declining with loss of diversity due to encroachment which decrease the vitality of oaks. The present explorative study compared results from a study conducted in 1994, with present species communities to observe if there has been change in species composition and what factors that can explain species diversity and composition. The results revealed that the overall species composition between 1994 and 2018 has changed. There were 130 species recorded in 2018 compared to 108 species in 1994 (31 new species were recorded in 2018, and 9 species lost from the study in 1994). There was a high species turnover recorded per individual tree, and the species composition between the living and encountered dead trees did not differ. Species composition was affected by canopy cover, and trunk circumference (CCA P-value 0.001 and 0.014 respectively). Unlike 1994, there were no variables in 2018 that could explain the association with species numbers. Warmer conditions recorded during the sampling period have probably led to increased flight activity of beetles and therefore increasing chances of capturing more species and individuals. The warmer conditions possibly shadowed the effects of the explanatory variables in explaining the changes in species numbers. Perhaps the change in species composition could also be attributed to existing management interventions that may be supporting an increasing species number of saproxylic beetles, however no strong conclusions could be drawn. Management interventions such as the recruitment of new oaks should be encouraged and intensified in order to provide habitats and support stable populations as the loss of oaks may lead to increased risk of extinction of the saproxylic beetles in the study area. Saproxylic beetles Guilds Species composition Canopy Cover Forest Regrowth Trunk Circumference Cavity size. Species turnover Ecology Ekologi
2	Regeneração florestal após desmatamento: estudo da região de Santarém, Pará, Brasil / Regrowth forest after deforestation: study on Santarém region, Para, Brazil Menezes, Diego Pinheiro de 15 March 2017 (has links) A superfície da terra foi modificada nos últimos 50 anos mais do que em qualquer outro período da História, mais intensa e rápida nos trópicos pela expansão das frentes de ocupação humana sobre floresta madura. A Amazônia brasileira, caracterizada pela alternância de ciclos econômicos extrativistas, exemplifica esse processo. Entre o abandono de áreas degradadas e a abertura de novas frentes de ocupação, ocorre a regeneração florestal. A floresta secundária tem uma reconhecida importância para o restabelecimento das funções dos ecossistemas e dos estoques de nutrientes perdidos da floresta madura, mas ignorados por muitos anos de taxas oficiais de desmatamento na Amazônia brasileira. Este estudo apresenta uma abordagem utilizando Análise de Imagens Baseada em Objetos Geográficos (GEOBIA) para classificar os estágios de sucessão secundária numa área com cerca de 11.124 km² na região de Santarém (Pará, Brasil). Dentre os resultados, foram produzidas 19 diferentes classificações cobrindo o período 1984 a 2016, que permitiu identificar a redução da floresta madura e da floresta secundária devido à expansão da fronteira agrícola. Outro resultado relevante foi a modelagem de uma árvore de decisão aplicável às imagens de refletância de superfície coletadas pelos satélites LANDSAT, processando esses atributos de classificação em um aplicativo de mineração de dados / The earth surface was modified in the last 50 years more than in any other period of the History, more intense and fast in the tropics by the expansion of human occupation frontiers on the mature forest. The Brazilian Amazon, characterized by alternating extractive economic cycles, exemplifies this process. Between the degraded areas abandonment and the new occupation fronts, forest regeneration takes place. The secondary forest has a recognized importance for the restoration of ecosystem functions and the nutrient stocks lost from the mature forest but ignored for many years of official deforestation rates in the Brazilian Amazon. In this study, an approach using Geographic Object-Based Imaging Analysis (GEOBIA) is presented to classify the stages of secondary succession in an area with near 11,124 km² on Santarém region (Pará State, Brazil). Among the results, 19 different classifications were produced covering the period 1984 to 2016, which allowed identify the reduction of mature forest and secondary forest due to agricultural frontier expansion. Another relevant result was the modeling of a decision tree applicable to surface reflectance images collected by the LANDSAT satellites, processing these classifications attributes in a data mining software Deforestation Desmatamento Floresta secundária Forest regrowth Geographic object-based image analysis Regeneração florestal Secondary forest
3	Regeneração florestal após desmatamento: estudo da região de Santarém, Pará, Brasil / Regrowth forest after deforestation: study on Santarém region, Para, Brazil Diego Pinheiro de Menezes 15 March 2017 (has links) A superfície da terra foi modificada nos últimos 50 anos mais do que em qualquer outro período da História, mais intensa e rápida nos trópicos pela expansão das frentes de ocupação humana sobre floresta madura. A Amazônia brasileira, caracterizada pela alternância de ciclos econômicos extrativistas, exemplifica esse processo. Entre o abandono de áreas degradadas e a abertura de novas frentes de ocupação, ocorre a regeneração florestal. A floresta secundária tem uma reconhecida importância para o restabelecimento das funções dos ecossistemas e dos estoques de nutrientes perdidos da floresta madura, mas ignorados por muitos anos de taxas oficiais de desmatamento na Amazônia brasileira. Este estudo apresenta uma abordagem utilizando Análise de Imagens Baseada em Objetos Geográficos (GEOBIA) para classificar os estágios de sucessão secundária numa área com cerca de 11.124 km² na região de Santarém (Pará, Brasil). Dentre os resultados, foram produzidas 19 diferentes classificações cobrindo o período 1984 a 2016, que permitiu identificar a redução da floresta madura e da floresta secundária devido à expansão da fronteira agrícola. Outro resultado relevante foi a modelagem de uma árvore de decisão aplicável às imagens de refletância de superfície coletadas pelos satélites LANDSAT, processando esses atributos de classificação em um aplicativo de mineração de dados / The earth surface was modified in the last 50 years more than in any other period of the History, more intense and fast in the tropics by the expansion of human occupation frontiers on the mature forest. The Brazilian Amazon, characterized by alternating extractive economic cycles, exemplifies this process. Between the degraded areas abandonment and the new occupation fronts, forest regeneration takes place. The secondary forest has a recognized importance for the restoration of ecosystem functions and the nutrient stocks lost from the mature forest but ignored for many years of official deforestation rates in the Brazilian Amazon. In this study, an approach using Geographic Object-Based Imaging Analysis (GEOBIA) is presented to classify the stages of secondary succession in an area with near 11,124 km² on Santarém region (Pará State, Brazil). Among the results, 19 different classifications were produced covering the period 1984 to 2016, which allowed identify the reduction of mature forest and secondary forest due to agricultural frontier expansion. Another relevant result was the modeling of a decision tree applicable to surface reflectance images collected by the LANDSAT satellites, processing these classifications attributes in a data mining software Desmatamento Floresta secundária Regeneração florestal Deforestation Forest regrowth Geographic object-based image analysis Secondary forest
4	Zur zeitlichen Prognose, räumlichen Verteilung und Heilungsdynamik von durch Wühlmäuse (Erdmaus, Microtus agrestis L., Rötelmaus, Clethrionomys glareolus Schreb. und Feldmaus, Microtus arvalis Pallas ) verursachten Nageschäden an Forstpflanzen / On the temporal prognosis, spatial distribution and healing dynamics of damage on young forest plants, caused by voles (Field vole, Microtus agrestis L., bank vole, Clethrionomys glareolus Schreb., and common vole, Microtus arvalis Pallas). Krueger, Frank 02 October 2002 (has links) No description available. 570 Biowissenschaften Biologie Forest Sciences and Forest Ecology Kurzschwanzmaus Microtinae Arvicolidae Microtus agrestis Microtus arvalis Clethrionomys glareolus Überschirmung Baumrindennahrung Nageschaden Forstverjüngung Forstjungwuchs Forstkultur Mäuseprognose Köder 100-Fallennächte Überwallung Pflanzeninhaltsstoffe Nährstoffe Kohlenhydrate Proteinaminosäure Tannine Phenole Attraktivität Voles Bark Barkfeeding Gnawing-damage Canopy-shading Forest-regrowth Wound-healing Vole-prognosis Bait Trapnight Chemical compounds Nutrients Carbon-hydrates Phenoles Tannins Attractivity 48.40 Forstwirtschaft 48.63 Nützlinge Schädlinge 48.99 Forstwirtschaft: Sonstiges

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