Patch Size Research Papers - Academia.edu (original) (raw)

Habitat fragmentation accompanies habitat loss, and drives additional biodiversity change; but few global biodiversity models explicitly analyse the effects of both fragmentation and loss. Here we propose and test the hypothesis that, as... more

Habitat fragmentation accompanies habitat loss, and drives additional biodiversity change; but few global biodiversity models explicitly analyse the effects of both fragmentation and loss. Here we propose and test the hypothesis that, as fragment area increases, species density (the number of species in a standardised plot) will scale with an exponent given by the difference between the exponents of the species-area relationships for islands (z ~ 0.25) and in contiguous habitat (z ~ 0.15), and test whether scaling varies between land uses. We also investigate the scaling of overall abundance and rarefaction-based richness, as some mechanisms make different predictions about how fragment area should affect them. The relevant data from the taxonomically and geographically broad PREDICTS database were used to model the three diversity measures, testing their scaling with fragment area and whether the scaling exponent varied among land uses (primary forest, secondary forest, plantation forest, cropland and pasture). In addition, the consistency of the response of species density to fragment area was tested across three well represented taxa (Magnoliopsida, Hymenoptera and 'herptiles'). Species density and total abundance showed area-scaling exponents of 0.07 and 0.16, respectively, and these exponents did not vary significantly among land uses; rarefaction-based richness by contrast did not increase consistently with area. These results suggest that the area-scaling of species density is driven by the area-scaling of total abundance, with additive edge effects (species moving into the small fragments from the surroundings) opposing-but not fully overcoming-the effect of fragment area on overall density of individuals. The interaction between fragment area and higher taxon (plants, vertebrates and invertebrates), which remained in the rarefied richness model, indicates that mechanisms may vary among groups.

We analyzed population dynamics and birth seasonality of wild bonobos at Wamba, Democratic Republic of the Congo, based on 20 years of observations (1976–1996). Wamba Bonobo infant mortality is much lower than that reported for... more

We analyzed population dynamics and birth seasonality of wild bonobos at Wamba, Democratic Republic of the Congo, based on 20 years of observations (1976–1996). Wamba Bonobo infant mortality is much lower than that reported for chimpanzees. This seemes to be related to several socioecological characteristics of bonobos: the use of abundant fruit and herbaceous foods, larger food patch size, female feeding priority, and the absence of infanticide. The mean interval between live births of 4.8 years is shorter than those reported for chimpanzees, and some females simultaneously carried and nursed two successive offspring. Mother–offspring conflicts, such as refusal of suckling attempts and interference with mothers' copulation, which are common in chimpanzees, are rare in Wamba bonobos. A birth peak seems to occur during the light rainy season from March to May, just after the season with the least rainfall. This timing of births is similar to those reported for chimpanzee populations, and might benefit both mother and offspring by maximizing the amount of time before the next dry season.

Peter T. Wolter1,2,* and Mark A. White1 1Center for Water and the Environment, Natural Resources Research Institute, University of Minnesota Duluth, Duluth, MN 55811, USA; 2Current address: University of Wisconsin – Green Bay, 2420... more

Peter T. Wolter1,2,* and Mark A. White1 1Center for Water and the Environment, Natural Resources Research Institute, University of Minnesota Duluth, Duluth, MN 55811, USA; 2Current address: University of Wisconsin – Green Bay, 2420 Nicolet Drive, Green Bay, WI 54311, ...

The soundscape, which is defined as the entire acoustic environment of an area, is a relevant biosemiotic ingredient of environmental complexity. It is composed of geophonies, anthrophonies, and biophonies where, in temperate biomes,... more

The soundscape, which is defined as the entire acoustic environment of an area, is a relevant biosemiotic ingredient of environmental complexity. It is composed of geophonies, anthrophonies, and biophonies where, in temperate biomes, birds are the major producers of the latter. The soundscape is heterogeneous in terms of space and time, and is affected by landscape features such as vegetation

... Patches in the Roosting and Foraging Ecology ... of isolated forest patches were not used as often as edges of forest patches close to mature forest, and the close adherence of northern long-earedbats and Indiana bats to hedgerows... more

... Patches in the Roosting and Foraging Ecology ... of isolated forest patches were not used as often as edges of forest patches close to mature forest, and the close adherence of northern long-earedbats and Indiana bats to hedgerows while commuting suggests that ...

We evaluated a comprehensive set of natural and land-use attributes that represent the major facets of urban development at fish monitoring sites in the rapidly growing Raleigh-Durham, North Carolina metropolitan area. We used principal... more

We evaluated a comprehensive set of natural and land-use attributes that represent the major facets of urban development at fish monitoring sites in the rapidly growing Raleigh-Durham, North Carolina metropolitan area. We used principal component and correlation analysis to obtain a nonredundant subset of variables that extracted most variation in the complete set. With this subset of variables, we assessed

In this study, the finite element method is used to analyse the behaviour of repaired cracks with bonded composite patches in mode I and mixed mode by computing the stress intensity factors at the crack tip. The effects of the patch size... more

In this study, the finite element method is used to analyse the behaviour of repaired cracks with bonded composite patches in mode I and mixed mode by computing the stress intensity factors at the crack tip. The effects of the patch size and the adhesive properties on the stress intensity factors variation were highlighted. The plot of the stress intensity

Clive A. McAlpine1,* and Teresa J. Eyre2 1School of Geography, Planning and Architecture, and The Ecology Centre, The University of Queensland, Brisbane, 4072, Australia; 2Sustainable Forestry Sciences Unit, Queensland Parks and Wildlife... more

Clive A. McAlpine1,* and Teresa J. Eyre2 1School of Geography, Planning and Architecture, and The Ecology Centre, The University of Queensland, Brisbane, 4072, Australia; 2Sustainable Forestry Sciences Unit, Queensland Parks and Wildlife Service, Indooroopilly, 4068, ...

Birds play vital roles as seed dispersers helping to maintain and restore plant communities. With restoration increasingly key to global conservation, it is important to understand the landscape attributes and bird community... more

Birds play vital roles as seed dispersers helping to maintain and restore plant communities. With restoration increasingly key to global conservation, it is important to understand the landscape attributes and bird community characteristics that most influence avian seed dispersal in human-altered landscapes. We examined bird community structure and seed-dispersal patterns in agricultural countryside in Costa Rica that is typical of