140 resultados para Woodlands
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The mean annual litterfall at two dry woodland sites in central Queensland was 1129 kg ha(-1) for an open E. populnea F. Muell. woodland (n = 2 years), and 2318 kg ha(-1) for a woodland dominated by E. cambageana Maiden (n = 1 year). Leaves formed the largest component of total litterfall, which varied seasonally with a spring-summer maximum. Annual litterfall at these sites conformed with a pattern of decreasing litter production with declining annual rainfall, consistent with a range of eucalypt-dominated communities.
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The spatial and breeding dynamics of koalas in sub-tropical woodlands at Blair Athol in central Queensland were intensively monitored between 1993 and 1998. Genetic relationships among koalas at this locality were studied to determine the breeding dynamics of males, including whether 'resident' or 'transient' males dominate as sires. Males and females were radio-collared and tracked periodically throughout each year of the study. Genotypes from hypervariable microsatellite loci identified uniquely all individuals and were used to analyse parentage as well as to determine population genetic parameters when compared with other regional localities. Koalas at Blair Athol comprise a population in genetic equilibrium. Gene diversity estimates show the population to be similar to other populations found in similar habitat in the region, and estimates of genetic differentiation among four regional populations showed that gene flow conforms to a model of isolation by distance. Analysis of parentage found that both resident and transient males sired about equal numbers of offspring. Familial DNA analysis revealed multiple paternities of successive young in this population. The conclusion from this study is that 'resident' status among males does not confer any advantage for parentage.
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The composition and the seasonality of the natural populations of Drosophila species in relation to the climatic variables temperature and rainfall were analyzed from September 1998 through October 1999 by monthly collections, in two woodlands in the Northwest of the State of São Paulo, Brazil. The diversity dominance component curves were inclined, reflecting low diversity and high dominance of few species. Among the 25 species recorded, Drosophila sturtevanti Duda, 1927 was the most frequent and abundant. On the opposite to data in literature, D. paranaensis Barros, 1950 abundance and frequency were greater than those from D. mercatorum Patterson & Wheeler, 1942. A positive correlation between abundance and rainfall was observed for D. nebulosa Sturtevant, 1916. These data are indicative of changes in the populations structure due to new adaptive strategies arised in response to environmental modifications.
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Strong winds, ice, snow and tornadoes are natural occurrences in Iowa forests. When severe, storms can cause extensive damage to forests by uprooting, wounding, bending and breaking trees. Storm damage management should involve a quick assessment to determine the extent of the damage, the need and potential for salvage, and woodland management efforts to return the woodland to a productive status.
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This report is on the effects of the tax reforam act of 1986 on timber production activites.
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PM2002B: People own wooded acreages and woodlands for a variety of reasons that may include: timber production, firewood production, recreation, wildlife habitat, aesthetics, and alternative forest products. Most of Iowa’s forestland is privately held, and the majority of ownership is fragmented into an average of ten acres (Forest Reserve Survey, 2004). In fact, the average size of an individual forest or woodlot ownership has been steadily declining for several years due in part to population growth, urban sprawl, and changes in land ownership. Studies indicate that the probability of a sustainable woodlot decreases as the population increases. At the same time, most woodlot owners want to be good stewards and protect and enhance the forest that they own. To achieve this goal, careful forest planning and management is required especially when managing the land for multiple objectives.
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Pamphlet describing the plant garlic mustard and it's threat to Iowa woodland and wildlife
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Garlic mustard is a rapidly spreading, highly invasive non-native plant. It was introduced from Europe in mid-1800 for medicinal and herbal uses. Came to the United States without predatory beetles or other natural controls. Threatens to rob us of healthy, diverse native woodlands.
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PEOPLE OWN WOODED ACREAGES and woodlands for a variety of reasons that may include: timber production, firewood production, recreation, wildlife habitat, aesthetics, and alternative forest products. Most of Iowa’s forestland is privately held, and the majority of ownership is fragmented into an average of ten acres (Forest Reserve Survey, 2004). In fact, the average size of an individual forest or woodlot ownership has been steadily declining for several years due in part to population growth, urban sprawl, and changes in land ownership. Studies indicate that the probability of a sustainable woodlot decreases as the population increases. At the same time, most woodlot owners want to be good stewards and protect and enhance the forest that they own. To achieve this goal, careful forest planning and management is required especially when managing the land for multiple objectives.