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Seasonal and Diurnal Patterns of Spatial Spread, Grouping Dynamics and Influence of Resources on a Free-Ranging Cattle Herd in a Semi-Arid Rangeland in South Texas, USACheleuitte-Nieves, Christopher 2011 August 1900 (has links)
Knowledge of scale-dependent factors that affect the distribution of ungulate herds, such as cattle, is essential for the development of more accurate predictive models of animal movement and the management of sustainable agriculture. Our objectives were to evaluate the seasonal and diurnal patterns of herd spread, explore grouping dynamics, and the influence of dominance ranks, seasonal changes in forage biomass, use of shade, water and supplemental feed areas on cattle distribution. Positional and activity information of eleven free-ranging Bonsmara, Bos taurus, cows were obtained at five minute intervals using Global Positioning System collars. We conducted a total of 12 trials each of three weeks from August 2007 to August 2009 in a 457ha shrub-dominated savanna in South Texas. Spread was obtained by calculating the average Euclidean distance of individuals to the center of the herd. The association software package, ASSOC1, was used to analyze spatio-temporal interactions. Normalized Difference Vegetation Index, an indicator of available forage biomass, was calculated using satellite imagery. Number of GPS fixes was used as an indicator of animal use of shade patches and water and supplemental feeding areas.
In this semi-arid environment, herd spread was greatest and subgroup division occurred during summer when forage biomass was high. Herd spread was the least and shade patches were used more during winter when forage biomass was low. Throughout the year spread was smallest and use of shade patches highest during the midday period compared to other periods of the day. Location of individuals in the center of the herd was not associated with their dominance ranking. There was no significant overall pattern of seasonal changes in cattle use of water and supplemental feeding areas.
Seasonal forage availability and shade patches seem to have a greater influence on herd dispersion patterns and grouping dynamics than any effect of social dominance.
Herd distribution is likely related to changes in forage biomass and temperature fluctuations which drive compensatory night-time feeding and thermoregulatory actions. Accurate ethological studies of herds depend on our ability to understand herd dynamics at multiple scales that affect and are relevant to animal's response to the landscape.
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Restauração florestal versus referência ecológica: utilização de indicadores ecológicos em ambientes ciliares na Floresta Ombrófila Mista / Forest restoration versus ecological reference: use of ecological indicators in riparian environments in Araucaria ForestStedille, Lilian Iara Bet 18 July 2016 (has links)
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Previous issue date: 2016-07-18 / PROMOP / The forest succession is a way to restore disturbed forest. Measure taken
to to the of permanent preservation areas (PPA’s) adequacy, mainly
riparian, wood-producing farms in the Santa Catarina Plateau South
region. Since the need for monitoring of these environments the main
objective of this study was to investigate the passive restoration in
riparian forest on Poço Grande and Campo de Dentro farms, with the
main focus for the survey of the tree composition. Only on the Poço
Grande farm has further study, envolvento environmental
compartmentalization in forest "reference" ecological formed by
fragments into more advanced successional stage and locations in
passive "restoration". Where it was included natural regeneration, seed
bank, the presence of grasses (Ocellochloa rudis (Nees) Zuloaga &
Morrone and Merostachys multiramea Hack), soil and canopy. The
results of the first chapter indicates that compartmentalization on the
farm Poço Grande showed that the sites in "restoration" have lower
density values, basal area, evenness among arboreal, and greater
participation of pioneers and autocóricos individuals. In the second
chapter between 23 variables, the existence of an ecological gradient of
diversity (Shannon index of tree) standing out among the other variables
involved. The second gradient formed is related to the presence of O.
rudis and higher soil pH and effective cation exchange capacity, even
without a relationship with a sector, may influence the formation of a
dense layer of biomass. The tree composition of Poço Grande and
Campo de Dentro farms for years of assessment 2011 and 2016, has
among the species most phytosociologic position. Between evaluated
the sampled species follow the same pattern of ecological groups and
dispersal syndromes, with high participation of zoochorous. Since the
Poço Grande farm, a decrease in the share of late side individuals and
increase climax individuals. Inside the Campo de Dentro farm was an
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increase in the proportion of pioneering individuals and decrease among
individuals climax. In both farms there was an increase of individuals
with syndrome zoochoric dispersion and a decrease of anemochorous
and autocóricos. The methodology of passive restoration proved to be a
promising alternative in locations with favorable landscape. Indicates
continuing the monitoring / A sucessão florestal é uma maneira de restaurar florestas alteradas.
Medida adotada para para a adequação de áreas de preservação
permanente (APP), principalmente ciliares, em fazendas produtoras de
madeira na região do Planalto Sul Catarinense. Visto a necessidade de
monitoramento destes ambientes o objetivo principal deste trabalho foi
investigar a restauração passiva nas áreas ciliares das fazendas Poço
Grande e Campo de Dentro, com enfoque principal para o levantamento
da composição arbórea. Apenas na fazenda Poço Grande tem-se um
estudo mais aprofundado, envolvento a setorização ambiental, em
floresta de “referência” ecológica formada por fragmentos em estádio
sucessional mais avançado e, locais em “restauração” passiva. Onde
incluiu-se o levantamento da regeneração natural, banco de sementes,
presença de gramíneas (Ocellochloa rudis (Nees) Zuloaga & Morrone e
Merostachys multiramea Hack), solos e dossel. Os resultados do
primeiro capítulo indicam que a setorização na fazenda Poço Grande
evidenciou que os locais em “restauração” apresentam menores valores
de densidade, área basal, equabilidade entre adultos, e maior
participação de indivíduos pioneiros e autocóricos. No segundo capítulo
entre 23 variáveis analisadas, a existência de um gradiente ecológico de
diversidade (índice de Shannon de árboreas) sobressaindo-se entre as
demais variáveis envolvidas. O segundo gradiente formado está
relacionado a presença de O. rudis, com maiores valores de pH do solo e
capacidade de troca catiônica efetiva, que mesmo sem uma relação com
algum setor, pode influênciar pela formação de uma densa camada de
biomassa. Ao avaliar a composição arbórea das fazendas Poço Grande e
Campo de Dentro, para os anos de avaliação 2011 e 2016, tem-se a
manutenção das espécies de maiores valores de importância. Entre os
anos avaliados as espécies seguem o mesmo padrão de grupos
ecológicos e síndromes de dispersão, com elevada participação de zoocó
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ricas. Sendo que na fazenda Poço Grande, ocorreu diminuição na
participação dos indivíduos secundários tardios e, aumento de
indivíduos clímax. Na fazenda Campo de Dentro ocorreu aumento na
proporção de indivíduos pioneiro e diminuição entre os indivíduos
clímax. Em ambas fazendas se verificou um aumento de indivíduos com
síndrome de dispersão zoocórica e, uma diminuição de anemocóricos e
autocóricos. A metodologia da restauração passiva mostrou-se como
uma alternativa promissora em locais com paisagem favorável. Indica-se
dar continuidade ao monitoramento
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