SABIIA - Sistema Aberto e Integrado de Informação em Agricultura (Sabiia)

Wear, David; U.S. Forest Service; dwear@fs.fed.us; Pye, John; U.S. Forest Service; jpye@fs.fed.us; Riitters, Kurt; U.S. Forest Service; kriiitters@fs.fed.us.

Methods are developed for forecasting the effects of population and economic growth on the distribution of interior forest habitat. An application to the southeastern United States shows that models provide significant explanatory power with regard to the observed distribution of interior forest. Estimates for economic and biophysical variables are significant and consistent with theory. Forecasts of interior forest based on the population and economic growth projected for the region are displayed by ecological section and province and by metropolitan statistical area (MSA). Loss of interior forests is expected to be especially high in certain ecological sections, including the southern Appalachian Piedmont in North and South Carolina, the Gulf prairies...

Tipo: Peer-Reviewed Reports

Palavras-chave: Fragmentation; Interior forest; Land use forecasts; North Carolina; South Carolina; Florida; Texas.

Ano: 2004

Detecting Critical Scales in Fragmented Landscapes

Keitt, Timothy; State University of New York at Stony Brook; Timothy.Keitt@StonyBrook.Edu; Urban, Dean L; Duke University; deanu@pinus.env.duke.edu; Milne, Bruce T; University of New Mexico; bmilne@sevilleta.unm.edu.

We develop methods for quantifying habitat connectivity at multiple scales and assigning conservation priority to habitat patches based on their contribution to connectivity. By representing the habitat mosaic as a mathematical "graph," we show that percolation theory can be used to quantify connectivity at multiple scales from empirical landscape data. Our results indicate that connectivity of landscapes is highly scale dependent, exhibiting a marked transition at a characteristic distance and varying significantly for organisms with different dispersal behavior. More importantly, we show that the sensitivity and importance of landscape pattern is also scale dependent, peaking at scales associated with the percolation transition. In addition, the...

Tipo: Peer-Reviewed Reports

Palavras-chave: Connectivity; Conservation in fragmented landscapes; Dispersal; Fragmentation; Habitat connectivity vs. dispersal distance; Landscape; Landscape graphs; Metapopulation; Percolation; Quantifying habitat connectivity at multiple scales; "stepping stone" patch; Strix occidentalis lucida..

Ano: 1997

Cumulative Effects of Barriers on the Movements of Forest Birds

St. Clair, Colleen Cassady; University of Alberta; cstclair@ualberta.ca.

Although there is a consensus of opinion that habitat fragmentation has deleterious effects on animal populations, primarily by inhibiting dispersal among remaining patches, there have been few explicit demonstrations of the ways by which degraded habitats actually constrain individual movement. Two impediments are primarily responsible for this paucity: it is difficult to separate the effects of habitat fragmentation (configuration) from habitat loss (composition), and conventional measures of fragmented habitats are assumed to be, but probably are not, isotropic. We addressed these limitations by standardizing differences in forest cover in a clearly anisotropic configuration of habitat fragmentation by conducting a homing experiment with three species...

Tipo: Peer-Reviewed Reports

Palavras-chave: Banff National Park; Golden-crowned Kinglet; Red-breasted Nuthatch; Yellow-rumped Warbler; Barriers; Connectivity; Corridor; Forest cover; Fragmentation; Habitat loss; Movement of forest birds; Roads.

Ano: 2001

Lack of Agreement on Fragmentation Metrics Blurs Correspondence between Fragmentation Experiments and Predicted Effects

Bogaert, Jan; University of Antwerp; jan.bogaert@ua.ac.be.

The direct correspondence between landscape fragmentation and its effects is still the subject of debate. Many widely accepted hypotheses are not supported by experiments. The issue of fragmentation measurement is addressed here. To predict the effects of fragmentation, it is essential to quantify the pattern of fragmentation. Despite the increased use of spatial analysis and available measures, experts have not yet reached an agreement on how to measure patterns of fragmented landscapes and, thus, unambiguous translation of experimental findings into conservation or management guidelines is hampered.

Tipo: Peer-Reviewed Reports

Palavras-chave: Fragmentation; Landscape metric; Spatial pattern.

Ano: 2003

Elevated Levels of Herbivory in Urban Landscapes: Are Declines in Tree Health More Than an Edge Effect?

Christie, Fiona J; University of Sydney; christie@bio.usyd.edu.au; Hochuli, Dieter F; University of Sydney; dieter@bio.usyd.edu.au.

Urbanization is one of the most extreme and rapidly growing anthropogenic pressures on the natural world. Urban development has led to substantial fragmentation of areas of natural habitat, resulting in significant impacts on biodiversity and disruptions to ecological processes. We investigated the levels of leaf damage caused by invertebrates in a dominant canopy species in urban remnants in a highly fragmented urban landscape in Sydney, Australia, by assessing the frequency and extent of chewing and surface damage of leaves in urban remnants compared to the edges and interiors of continuous areas of vegetation. Although no difference was detected in the frequency of leaves showing signs of damage at small, edge, and interior sites, small sites suffered...

Tipo: Peer-Reviewed Reports

Palavras-chave: Urban landscapes; Herbivory; Invertebrates; Urbanization; Remnant vegetation; Fragmentation; Leaf damage; Australia.

Ano: 2005

Quantifying the Road-Effect Zone: Threshold Effects of a Motorway on Anuran Populations in Ontario, Canada

Eigenbrod, Felix; Geomatics and Landscape Ecology Research Laboratory, Department of Biology, Carleton University, Ottawa, Canada; felix.eigenbrod@gmail.com; Hecnar, Stephen J.; Department of Biology, Lakehead University, Thunder Bay, Ontario, Canada; shecnar@lakeheadu.ca; Fahrig, Lenore; Geomatics and Landscape Ecology Research Laboratory, Department of Biology, Carleton University, Ottawa, Ontario Canada; lfahrig@ccs.carleton.ca.

Tipo: Peer-Reviewed Reports

Palavras-chave: Accessible habitat; Amphibian decline; Anuran populations; Ecological thresholds; Forests; Fragmentation; Habitat loss; Piecewise regression; Road ecology..

Ano: 2009

Animal Dispersal in Fragmented Habitat: Measuring Habitat Connectivity, Corridor Use, and Dispersal Mortality

Brooker, Lesley; CSIRO Sustainable Ecosystems; lesley.brooker@csiro.au; Brooker, Michael; CSIRO Wildlife and Ecology; M.Brooker@per.dwe.csiro.au; Cale, Peter; CSIRO Wildlife and Ecology; P.Cale@per.dwe.csiro.au.

We used a spatially explicit dispersal simulation to generate movement frequencies and distances for comparison with real dispersal frequencies collected in the field from two habitat-specific, sedentary bird species. The relationship between these two data sets allowed us to (1) test the hypothesis that the study species used corridor routes during dispersal; (2) measure the degree of reliance on corridor continuity; (3) estimate the rate of dispersal mortality with respect to distance traveled, and (4) give examples of how the model can be used to assess habitat connectivity with respect to similarly behaved species. We found that Blue-breasted Fairy-wrens and White-browed Babblers both used corridor routes during dispersal. Blue-breasted Fairy-wrens...

Tipo: Peer-Reviewed Reports

Palavras-chave: Animal dispersal; Blue-breasted Fairy-wren; Dispersal model; Dispersal mortality; Fragmentation; Habitat connectivity; Malurus pulcherrimus; Pomatostomus superciliosus; Spatially explicit dispersal; Vegetation corridors; White-browed Babbler..

Ano: 1999

Patch Size and Population Density: the Effect of Immigration Behavior

Bowman, Jeff; Ontario Ministry of Natural Resources; jeff.bowman@mnr.gov.on.ca; Cappuccino, Naomi; Carleton University; ncappucc@ccs.carleton.ca; Fahrig, Lenore; Carleton University; lfahrig@ccs.carleton.ca.

Many habitat fragmentation experiments make the prediction that animal population density will be positively related to fragment, or patch, size. The mechanism that is supposed to result in this prediction is unclear, but several recent reviews have demonstrated that population density often is negatively related to patch size. Immigration behavior is likely to have an important effect on population density for species that do not show strong edge effects, for species that have low emigration rates, and during short-term habitat fragmentation experiments. We consider the effect that different kinds of immigration behaviors will have on population density and we demonstrate that only a minority of possible scenarios produce positive density vs. patch size...

Tipo: Peer-Reviewed Reports

Palavras-chave: Colonization; Connectivity; Dispersal; Edge; Emigration; Experiment; Fragmentation; Immigration; Individuals-area relationships; Insular; Island biogeography; Landscape.

Ano: 2002

Using structured decision making with landowners to address private forest management and parcelization: balancing multiple objectives and incorporating uncertainty

Ferguson, Paige F. B.; Department of Biological Sciences, University of Alabama; Warnell School of Forestry and Natural Resources, University of Georgia; pfferguson@ua.edu; Conroy, Michael J; Warnell School of Forestry and Natural Resources, University of Georgia; mconroy@uga.edu; Chamblee, John F; Department of Anthropology, University of Georgia; chamblee@uga.edu; Hepinstall-Cymerman, Jeffrey; Warnell School of Forestry and Natural Resources, University of Georgia; jhepinst@uga.edu.

Parcelization and forest fragmentation are of concern for ecological, economic, and social reasons. Efforts to keep large, private forests intact may be supported by a decision-making process that incorporates landowners’ objectives and uncertainty. We used structured decision making (SDM) with owners of large, private forests in Macon County, North Carolina. Macon County has little land use regulation and a history of discordant, ineffective attempts to address land use and development. We worked with landowners to define their objectives, identify decision options for forest management, build a Bayesian decision network to predict the outcomes of decisions, and determine the optimal and least-desirable decision options. The optimal forest...

Tipo: Peer-Reviewed Reports

Palavras-chave: Bayesian decision network; Conservation easement; Decision analysis; Forestry; Fragmentation; Heritage; Present-use value; Sustainability; Timber harvest.

Ano: 2015

Land-Use and Land Cover Dynamics in South American Temperate Grasslands

Understanding Fragmentation: Getting closer to 42

In the Río de la Plata grasslands (RPG) biogeographical region of South America, agricultural activities have undergone important changes during the last 15–18 years because of technological improvements and new national and international market conditions. We characterized changes in the landscape structure between 1985–1989 and 2002–2004 for eight pilot areas distributed across the main regional environmental gradients. These areas incorporated approximately 35% of the 7.5 × 105 km&#178 of the system. Our approach involved the generation of land-use and land cover maps, the analysis of landscape metrics, and the computation of annual transition probabilities between land cover types. All of the...

Tipo: Peer-Reviewed Reports

Palavras-chave: Campos; Fragmentation; Grasslands; Land use; Landscape dynamics pampas; Remote sensing; Spatial metrics.

Ano: 2008

Bissonette, John; Utah State University; john.bissonette@usu.edu; Storch, Ilse; Wildlife Research and Management Unit, Technical University of Munich and Max Pl; ilse.storch@t-online.de.

Tipo: Peer-Reviewed Reports

Palavras-chave: Disturbance metrics; Fragmentation; Pulsed resources; Spatial dynamics; Temporal dynamics.

Ano: 2003

Monitoring Current Status of and Trends in Boreal Forest Land Use in Russian Karelia

Burnett, Charles; University of Salzburg; charles.burnett@sbg.ac.at; Fall, Andrew; Simon Fraser University; fall@cs.sfu.ca; Tomppo, Erkki; Finnish Forest Research Institute; Erkki.Tomppo@metla.fi; Kalliola, Risto; University of Turku; risto.kalliola@utu.fi.

Some of the last remaining near-natural boreal forest landscapes in northern Europe can be found in the Russian Karelia near its border with Finland. Currently, these forests are facing strong exploitation pressure in the form of extensive clearcuts. Demand for conservation is also high. We characterize the boreal forest landscape in the region and assess the impacts of past and potential management actions through a mapping and modeling study that synthesizes methods from landscape ecology, remote sensing, and simulation modeling. The forests of the study area were mapped using techniques for interpreting multitemporal satellite images and detecting changes. The species composition and structure of the forests were estimated using the multisource...

Tipo: Peer-Reviewed Reports

Palavras-chave: Karelia; Russia; Finland; Boreal forest; Conservation policy; Dynamic modeling; Fragmentation; Land use; GIS.

Ano: 2003

Relationship between fragmentation, degradation and native and exotic species richness in an Andean temperate forest of Chile

Gayana Botánica

ROJAS,ISABEL; BECERRA,PABLO; GÁLVEZ,NICOLÁS; LAKER,JERRY; BONACIC,CRISTIÁN; HESTER,ALISON.

Human impact such as forest fragmentation and degradation may have strong effects on native and exotic plant communities. In addition, these human-caused disturbances occur mostly in lowlands producing greater fragmentation and degradation there than in higher elevations. Plant invasion should be greater in more fragmented and degraded forests and hence lowlands should be more invaded than higher elevations. In turn, native species richness should be negatively related to fragmentation and degradation and hence greater in higher elevations within a forest type or elevation belt. We assessed these hypotheses in an Andean temperate forest of southern Chile, Araucanía Region. We recorded the vascular plant composition in twelve fragments of different size,...

Tipo: Journal article

Palavras-chave: Fragmentation; Forest degradation; Elevation gradient; Invasion; Plant diversity.

Ano: 2011

URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432011000200006

The importance of isolated patches for maintaining local bird biodiversity and ecosystem function: a case study from the Pernambuco Center of Endemism, Northeast Brazil

Campos,Leila F. A. S.; Teixeira,Bruno P.; Efe,Márcio A..

ABSTRACT The Atlantic Forest has been highly fragmented, with the Pernambuco Center of Endemism (PCE) one of the priority areas for conservation. The Mata do Cedro forest, located in Alagoas state, northeastern Brazil, is a forest fragment within the PCE surrounded by a matrix of sugarcane that acts as a refuge for several threatened bird species, some of which are endemic to the region. Here, we characterize the bird community in Mata do Cedro using measures of species abundance, frequency of occurrence, habitat use and sensitivity to human disturbance. The functional role of species was investigated with a functional dendrogram. We registered 111 species, most resident and forest dependent. The most representative trophic categories were insectivores...

Sexual and asexual reproduction in Didemnum rodriguesi (Ascidiacea, Didemnidae)

Palavras-chave: Atlantic Forest; Fragmentation; Functional groups; Community structure; Alagoas.

Ano: 2018

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212018000100221

Ritzmann,Nicole F.; Rocha,Rosana M. da; Roper,James J..

Sexual and asexual reproduction and associated population dynamics were investigated in the colonial ascidian Didemnum rodriguesi Rocha & Monniot, 1993 (Didemnidae) in southern Brazil. Investment in sexual (production of new individuals) and asexual (colony growth) reproduction was compared between seasons. Permanently marked quadrats were repeatedly photographed to measure changes in colonies. Eggs and larvae were counted monthly in collected colonies. This species alternates seasonally between sexual (summer) and asexual (winter) reproduction. In summer, colonies were smaller, brooded eggs and larvae and recruitment rates were greater, while in winter, colony size was larger and eggs and larvae were absent. There is a relationship between...

Reproductive success of Trypoxylon (Trypargilum) lactitarse (Hymenoptera: Crabronidae) in a fragmented landscape

Palavras-chave: Reproductive investment; Sexual reproduction; Fragmentation; Tunicates.

Ano: 2009

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212009000100015

Oliveira,Grayce Kelly Costa; Elias,Marcos Antonio da Silva; Bergamini,Leonardo Lima; Franceschinelli,Edivani Villaron.

ABSTRACT Fragmentation of natural vegetation often implies a reduction in local species richness and abundance. The resources used by bees and wasps for feeding and nesting are distributed quite irregularly in fragmented environments, which influences their foraging behavior, occurrence patterns and reproductive success. The objective of the present work was to determine if the size of native vegetation remnants influences the reproductive success of the solitary wasp species Trypoxylon (Trypargilum) lactitarse Saussure, 1867. Trap-nests were established along the edges of forest fragments of different sizes located in municipalities in the central region of the state of Goiás, Brazil. The nests were used to quantify nesting rate, number of cells with...

The phyllostomid bat (Mammalia, Chiroptera) assemblage in a fragmented landscape in Midwestern Brazil

Palavras-chave: Fragmentation; Reproductive success; Trap-nests.

Ano: 2020

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212020000100204

Odon,Anderson; Bordignon,Marcelo O.; Dornelles,Guilherme D. P..

ABSTRACT Bats are the second largest order of mammals, with varying feeding habits and great ecological significance. Anthropization has several important effects on animal communities and the Brazilian Cerrado, a Neotropical savannah, has been severely affected by human activity. The objective of this study was to evaluate phyllostomid bat assemblage distributions in the different landscape formations of a modified savannah. Using mist nets, we performed 36 sampling nights between 2015 and 2016. The sampling effort was 23,328 m².h and was equally distributed over three landscape formations: a large fragment, riparian forest, and small fragments. We compared capture rates, richness, diversity, similarity, and feeding guilds for the three formations. We...