Spelling suggestions: "subject:"coexistence mechanisms"" "subject:"koexistence mechanisms""
1 |
The role of heterogeneity in spatial plant population dynamicsvan Waveren, Clara-Sophie 24 October 2016 (has links)
No description available.
|
2 |
Coleta de recursos gluc?dios por vespas sociais: mecanismos que regem seu padr?o de atividade di?rioS?, Cassia Alves de 21 March 2013 (has links)
Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2016-03-12T00:12:47Z
No. of bitstreams: 1
Disserta??o - C?ssia Alves de S?.pdf: 408040 bytes, checksum: a24d9c29b600bca2f7903bdca077b81c (MD5) / Made available in DSpace on 2016-03-12T00:12:47Z (GMT). No. of bitstreams: 1
Disserta??o - C?ssia Alves de S?.pdf: 408040 bytes, checksum: a24d9c29b600bca2f7903bdca077b81c (MD5)
Previous issue date: 2013-03-21 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The daily activity pattern of social wasps can be influenced by different mechanisms such as environmental restrictions or interspecific interactions. However, the importance of interspecific interactions on the determination of the daily activity patterns may decrease on habitats with high environmental complexity. In this sense, we evaluated two hypotheses in order to understand what factors affect the daily activity patterns of social wasps: 1) The abundance overlap of different species during the day is lower when environmental complexity is greater, and 2) Thermal restrictions may constrain wasp activity. We counted the abundance of several wasp species foraging throughout the day on extrafloral nectaries in two plantations of caupi bean: on esurrounded by a pasture matrix (low structural complexity) and the other surrounded by fruit trees (high structural complexity). Afterwards, we evaluated the abundance overlap during the day, the abundance variations per hour and the preferential time of start and end of day activity. Temporal overlapping between species during the day was high for both plantations. The majority of species had a bimodal abundance pattern, with one abundance peak during the morning and the other during the afternoon. Species of major size started their activity during later hours, while species of minor size were active on every hour. These results indicate two scenarios: first, competition seems to below in these communities and second, temperature seems to be particularly restrictive for the activity of species of greater size. / A coleta de recursos gluc?dios pelas vespas sociais ao longo do dia pode variar como resposta a diferentes mecanismos, podendo responder a restri??es ambientais ou a intera??es interespec?ficas. Por?m, a import?ncia relativa das intera??es interespec?ficas pode ser reduzida em sistemas com maior complexidade ambiental. Para compreender esse efeito, avaliamos as seguintes hip?teses: 1) A sobreposi??o nos hor?rios de forrageamento das esp?cies de vespas sociais ao longo do dia ? menor quando a complexidade ambiental ? maior e 2) o padr?o de atividade di?rio das vespas ao longo do dia ? determinado por restri??es ambientais. Para isso, quantificamos a abund?ncia de diferentes esp?cies de vespas sociais forrageando em nect?rios extraflorais em duas planta??es de do feij?o caupi: uma circundada por matriz de pasto (baixa complexidade estrutural) e outra por frut?feras (alta complexidade estrutural). Iniciamos as observa??es e coletas ao longo do dia, depois que os NEFs do feij?o estavam ativos, e avaliamos o padr?o de sobreposi??o temporal de abund?ncia, o padr?o de abund?ncia em cada hor?rio, bem como a rela??o entre o hor?rio de in?cio e fim de atividade e o tamanho de cada esp?cie. A sobreposi??o temporal foi alta para as duas ?reas. O padr?o de abund?ncia foi bimodal ao longo do dia. As esp?cies de maior tamanho entraram em atividade em hor?rios mais tardios enquanto as esp?cies de pequeno tamanho n?o apresentaram um padr?o de inicio e fim de atividade. Esses resultados indicam que a competi??o entre esp?cies de vespas sociais ? baixa, permitindo a alta sobreposi??o do hor?rio de atividade nas duas ?reas. J? a temperatura parece restringir o hor?rio de atividade para vespas de grande porte.
|
Page generated in 0.0757 seconds