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Arquitetura de copas de espécies da caatinga: Um reflexo do estresse hídrico na vegetação do semiárido brasileiro / Tree crowns architecture of Caatinga species: a reflection of the hydric stress in the semiarid lands.Cavalcante, Carolline Barros 27 February 2014 (has links)
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Previous issue date: 2014-02-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The crown architecture is influenced by genetic and environmental factors, which are intermediated by plant hormones. In order to avoid radiation excess and water loss through transpiration, the species from arid lands such as Caatinga developed survival strategies. In Caatinga lands, the species were grouped according to their leaf phenology and it’s expected that the different phenologic patterns be related to the morphologic characteristics of the plant, including its crown. In this case, this study aimed to characterize the crown architecture of groups having different leaf phenologies from Caatinga and understand the existing relations. Nine crown species were represented, being three evergreen, three 2- to 3-month deciduous and three 4- to 6-month, and for each species three individuals were analyzed, totaling up 27. For each individual, it was accounted the number of connectors, regular, final and emission nodes, besides the distances between the different kinds of nodes. The results showed that among the analyzed groups, the greatest averages to the number of nodes and connectors were found in the 2- to 3-month-old deciduous group, followed by the evergreen group, and finally the 4- to 6-month-old deciduous group. What concerns the distances, only the distance between the final adjoining nodes differed among the groups, in a way that the evergreen trees showed the lowest average. The less segmented deciduous canopies of 4-6 months facilitate the quick distribution of resources throughout the plant, while canopies more segmented, as 2-3 months avoid self-shading of leaves along the branches. Evergreen species showed complexity of canopy reduced with self-shading avoiding excessive water loss, indicating a relationship between leaf phenology and canopy architecture in species of the Caatinga. / A arquitetura copa é influenciada por fatores genéticos e ambientais, que são intermediados por hormônios vegetais. Para evitar o excesso de radiação e a perda de água por transpiração, as espécies de ambientes áridos como a Caatinga desenvolveram estratégias de sobrevivência. Na Caatinga, as espécies foram agrupadas de acordo com a sua fenologia foliar e espera-se que os diferentes padrões fenológicos estejam relacionados às características morfológicas da planta, inclusive de sua copa. Sendo assim, objetivo deste estudo foi caracterizar a arquitetura da copa de grupos com diferentes fenologias foliares da Caatinga e compreender as relações existentes. Foram representadas as copas nove espécies, sendo três perenifólias, três decíduas de 2-3 meses e três decíduas de 4-6 meses e para cada espécie foram analisados três indivíduos, totalizando 27. Para cada indivíduo foi contabilizado o número de conectores, nós regulares, nós finais e nós de emissão, além das distâncias entre os diferentes tipos de nós. Os resultados mostraram que entre os grupos analisados, as maiores médias para o número de nós e conectores foram apresentadas pelo grupo das decíduas de 2-3 meses, seguido pelo grupo das perenifólias e por fim, pelo grupo das decíduas de 4-6 meses. Para as distâncias, apenas a distância entre nós finais vizinhos diferiu entre os grupos, de modo que o grupo das perenifólias apresentou a menor média. As copas menos segmentadas das decíduas de 4-6 meses facilitam a distribuição de recursos por toda a planta de forma rápida, enquanto que copas mais segmentadas, como das decíduas de 2-3 meses evitam o autosombreamento das folhas ao longo dos ramos. Espécies perenifólias apresentaram complexidade de copa reduzida, com autosombreamtento evitando a perda excessiva de água, evidenciando uma relação entre a fenologia foliar e a arquitetura da copa em espécies da Caatinga.
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Automatisk gallringsuppföljning i olika beståndstyper : Ingående beståndsvariablers inverkan på precisionen hos programvaran hprGallringHäggeborg, Johan January 2017 (has links)
För att kontrollera så gallringar utförs på ett korrekt sätt genomförs kontinuerliga kvalitetskontroller, dels som enkla egenuppföljningar av maskinförarna men även som mer omfattande gallringsuppföljningar av skogsbolag och skogsägarföreningar. Eftersom dessa kontroller är tidskrävande så görs i dagsläget enbart stickprovskontroller. Skogforsk har utvecklat ett program vid namn hprGallring, som utifrån skördardata beräknar beståndsvariabler och gör en prognos för det kvarvarande beståndet. Syftet med den här studien har varit att undersöka om precisionen i hprGallring är tillräckligt bra för att vara tillfredsställande och på så vis kunna minska ner det manuella arbetet. Resultaten pekar på att hprGallring nästan alltid överskattar grundytan och volym något. Allra tydligast blir det i gallringar som är riktade mot ett visst trädslag, dvs. när trädslagsfördelningen i gallringsuttaget skiljer sig avsevärt från trädslagsfördelningen i det ursprungliga beståndet. I dessa fall stämmer även den prognostiserade trädslagsfördelningen i det kvarvarande beståndet dåligt. / Continuous controls are made to see if the thinning is done as specified. This is made by self-controls by the harvester drivers or more comprehensive controls by the logging companies. Those controls are done by random samples since they are very time consuming. Skogforsk has developed software named hprGallring, which uses harvester data and mathematical algorithms to calculate stand variables and forecasting the remaining stand after thinning. The purpose with this study has been to investigate if hprGallrings forecast is good enough to reduce the manual work. The results show that hprGallring seems to overestimate the basal area and volume. This is most obvious in stands were the thinning are concentrated against a specific sort of wood. The forecast for tree composition in the remaining stand are in these cases very inaccurate.
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