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Efeito de borda em um contexto de Florestas Urbanas: Resultantes estruturais de usos pret?ritos do solo / Edge effect in urban forests: structural resultants of land use history.Monteiro, Flavia de Carvalho Dias 25 March 2008 (has links)
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Previous issue date: 2008-03-25 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPQ / The Atlantic Rain Forest is one of the world?s most endangered biomes. Long before its
discovery by western civilization, the forest had already been occupied and used by native
populations. The increasing occupation of this biome has generated landscapes composed of
a mosaic of forests of different ages that resulted from its usage and that overlap in space and
time. Remaining fragments are still subject to manmade impacts including edge effects.
Based on these concepts, a study was conducted aiming at understanding the edge effects, on
structure and composition, of two areas of Atlantic Rain Forest in the Pedra Branca State Park
in Rio de Janeiro, RJ; one located in the valley basins (Ca?ambe river basin), and the other at
the limit of the drainage (Grande river basin). At each area, were choosed two sites; one near
to the edge and other over 100m from the edge (forest interior). The sites were: valley basin?s
edge (Bfv), valley basin?s interior (Ifv), limit of the drainage?s edge (Bdd) and limit of the
drainage?s interior (Idd). Changes caused by the existence of a edge, included the assess of a
biotic edge effects, using for it changes in the species richness, individuals density, diameter
and height. Individual trees and shrubs with diameter at breast height (dbh) > 5 cm were
sampled within 32 plots of 10 x 10 m for a total sample size of 0.32 ha. The samples yielded
309 individuals of 77 species, 70 genera and 32 families. The total basal area was 28,89 m2/ha
and density was 966 ind./ha. Leguminosae, Meliaceae e Sapotaceae were found to be the
richest families. The number of total species is comparable to the referenced values for
preserved forests, inventoried in the southeast. The edges species richness (Bfv and Ifv)
similar to the interiors species richness (Ifv and Idd). Mean diameter varied form 32, 9 cm and
36,2 cm in the edges and 42,2 cm and 53,1 cm in the forests interiors. Probably, the sampled
edges finds itself in a state of natural regeneration and represents an inicial successional state,
different to the intermediary sucessional state in the interiors. The index of S?rensen
between the four sites may occurs due to the different slope orientation, geomorphologic
situation and land use history. / A Mata Atl?ntica ? um dos biomas mais amea?ados do mundo. Desde antes de sua descoberta
pelo ocidente, a floresta j? era utilizada e apropriada por popula??es nativas. Com a
intensifica??o da ocupa??o deste bioma, geraram-se paisagens compostas por mosaicos de
florestas de diferentes idades, provenientes de usos diversos, que se sobrep?em no tempo e no
espa?o. Os fragmentos remanescentes est?o ainda sujeitos a v?rios impactos antr?picos, tais
como os efeitos de borda. Desta forma, procura-se analisar como a din?mica homem-natureza
exerce suas influ?ncias na transforma??o da paisagem. Procurou-se compreender os efeitos de
borda na estrutura e composi??o de duas ?reas de Mata Atl?ntica, localizadas no Parque
Estadual de Pedra Branca na cidade do Rio de Janeiro, RJ; uma localizada no fundo de vale
(bacia do rio Ca?ambe) e a outra no divisor de drenagem (bacia do rio Grande). Em cada ?rea
de estudo, foram selecionados 2 s?tios amostrais; um adjacente ? borda e o outro distante a
cerca de 100 metros da borda (interior de floresta). Os quatro s?tios amostrais foram
denominados borda de fundo de vale (Bfv), interior de fundo de vale (Ifv), borda do divisor
de drenagem (Bdd) e interior do divisor de drenagem (Idd). As mudan?as provocadas pela
exist?ncia de uma borda envolveram avalia??es de efeitos biol?gicos, utilizando como
ferramenta a riqueza de esp?cies, a densidade, estrutura diam?trica e de tamanho dos
indiv?duos. Para a amostragem das ?reas, foram implantadas 32 parcelas, de 100 m? (0,32 ha),
sendo que o crit?rio de inclus?o adotado foi DAP ? 5 cm. Foram amostrados 309 indiv?duos
de 77 esp?cies, 70 g?neros e 32 fam?lias. A ?rea basal total foi de 28,89 m2/ha e densidade de
966 ind./ha. Leguminosae, Meliaceae e Sapotaceae apresentaram os maiores valores de
riqueza de esp?cies. O n?mero total de esp?cies amostradas foi compat?vel com forma??es
assemelhadas do sudeste Brasileiro. As bordas apresentaram uma riqueza de esp?cies pr?xima
? das ?reas interioranas. Os di?metros m?dios variaram entre 32,9 cm e 36,2 cm nas bordas e
42,2 cm e 53,1cm nos interiores de floresta. Provavelmente, as bordas amostradas encontramse
em est?gio de regenera??o natural, representando grupos sucessionais iniciais, distintos
daqueles que ocorrem no interior da floresta. A n?o similaridade das ?reas, aferida com o uso
do ?ndice de S?rensen mostrou que cada uma das ?reas ? constitu?da por conjuntos de
esp?cies caracter?sticas. Estes resultados podem ser atribu?dos ?s diferentes orienta??es de
encosta, situa??o geomorfol?gica e aos usos pret?ritos das ?reas.
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Efeito de borda em um contexto de florestas urbanas: resultantes estruturais de usos pret?ritos do solo / Edge effect in urban forests: structural resultants of land use historyDIAS, Flavia de Carvalho 25 March 2008 (has links)
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Previous issue date: 2008-03-25 / CNPq / The Atlantic Rain Forest is one of the world?s most endangered biomes. Long before its discovery by western civilization, the forest had already been occupied and used by native populations. The increasing occupation of this biome has generated landscapes composed of a mosaic of forests of different ages that resulted from its usage and that overlap in space and time. Remaining fragments are still subject to manmade impacts including edge effects. Based on these concepts, a study was conducted aiming at understanding the edge effects, on structure and composition, of two areas of Atlantic Rain Forest in the Pedra Branca State Park in Rio de Janeiro, RJ; one located in the valley basins (Ca?ambe river basin), and the other at the limit of the drainage (Grande river basin). At each area, were choosed two sites; one near to the edge and other over 100m from the edge (forest interior). The sites were: valley basin?s edge (Bfv), valley basin?s interior (Ifv), limit of the drainage?s edge (Bdd) and limit of the drainage?s interior (Idd). Changes caused by the existence of a edge, included the assess of a biotic edge effects, using for it changes in the species richness, individuals density, diameter and height. Individual trees and shrubs with diameter at breast height (dbh) > 5 cm were sampled within 32 plots of 10 x 10 m for a total sample size of 0.32 ha. The samples yielded 309 individuals of 77 species, 70 genera and 32 families. The total basal area was 28,89 m2/ha and density was 966 ind./ha. Leguminosae, Meliaceae e Sapotaceae were found to be the richest families. The number of total species is comparable to the referenced values for preserved forests, inventoried in the southeast. The edges species richness (Bfv and Ifv) similar to the interiors species richness (Ifv and Idd). Mean diameter varied form 32, 9 cm and 36,2 cm in the edges and 42,2 cm and 53,1 cm in the forests interiors. Probably, the sampled edges finds itself in a state of natural regeneration and represents an inicial successional state, different to the intermediary sucessional state in the interiors. The index of S?rensen between the four sites may occurs due to the different slope orientation, geomorphologic situation and land use history. / A Mata Atl?ntica ? um dos biomas mais amea?ados do mundo. Desde antes de sua descoberta pelo ocidente, a floresta j? era utilizada e apropriada por popula??es nativas. Com a intensifica??o da ocupa??o deste bioma, geraram-se paisagens compostas por mosaicos de florestas de diferentes idades, provenientes de usos diversos, que se sobrep?em no tempo e no espa?o. Os fragmentos remanescentes est?o ainda sujeitos a v?rios impactos antr?picos, tais como os efeitos de borda. Desta forma, procura-se analisar como a din?mica homem-natureza exerce suas influ?ncias na transforma??o da paisagem. Procurou-se compreender os efeitos de borda na estrutura e composi??o de duas ?reas de Mata Atl?ntica, localizadas no Parque Estadual de Pedra Branca na cidade do Rio de Janeiro, RJ; uma localizada no fundo de vale (bacia do rio Ca?ambe) e a outra no divisor de drenagem (bacia do rio Grande). Em cada ?rea de estudo, foram selecionados 2 s?tios amostrais; um adjacente ? borda e o outro distante a cerca de 100 metros da borda (interior de floresta). Os quatro s?tios amostrais foram denominados borda de fundo de vale (Bfv), interior de fundo de vale (Ifv), borda do divisor de drenagem (Bdd) e interior do divisor de drenagem (Idd). As mudan?as provocadas pela exist?ncia de uma borda envolveram avalia??es de efeitos biol?gicos, utilizando como ferramenta a riqueza de esp?cies, a densidade, estrutura diam?trica e de tamanho dos indiv?duos. Para a amostragem das ?reas, foram implantadas 32 parcelas, de 100 m? (0,32 ha), sendo que o crit?rio de inclus?o adotado foi DAP ? 5 cm. Foram amostrados 309 indiv?duos de 77 esp?cies, 70 g?neros e 32 fam?lias. A ?rea basal total foi de 28,89 m2/ha e densidade de 966 ind./ha. Leguminosae, Meliaceae e Sapotaceae apresentaram os maiores valores de riqueza de esp?cies. O n?mero total de esp?cies amostradas foi compat?vel com forma??es assemelhadas do sudeste Brasileiro. As bordas apresentaram uma riqueza de esp?cies pr?xima ? das ?reas interioranas. Os di?metros m?dios variaram entre 32,9 cm e 36,2 cm nas bordas e 42,2 cm e 53,1cm nos interiores de floresta. Provavelmente, as bordas amostradas encontram-se em est?gio de regenera??o natural, representando grupos sucessionais iniciais, distintos daqueles que ocorrem no interior da floresta. A n?o similaridade das ?reas, aferida com o uso do ?ndice de S?rensen mostrou que cada uma das ?reas ? constitu?da por conjuntos de esp?cies caracter?sticas. Estes resultados podem ser atribu?dos ?s diferentes orienta??es de encosta, situa??o geomorfol?gica e aos usos pret?ritos das ?reas.
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Past and present management influences the seed bank and seed rain in a rural landscape mosaicAuffret, Alistair G., Cousins, Sara A. O. January 2011 (has links)
1. Seed bank and seed rain represent dispersal in time and space. They can be important sources of diversity in the rural landscape, where fragmented habitats are linked by their histories. 2. Seed bank, seed rain and above-ground vegetation were sampled in four habitat types (abandoned semi-natural grassland (ABA), grazed former arable field (FAF), mid-field islet (MFI) and grazed semi-natural grassland (SNG)) in a rural landscape in southern Sweden, to examine whether community patterns can be distinguished at large spatial scales and whether seed bank and seed rain are best explained by current, past or intended future vegetation communities. 3. We counted 54 357 seedlings of 188 species from 1190 seed bank and 797 seed rain samples. Seed bank, seed rain and above-ground vegetation communities differed according to habitat. Several species characteristic of managed grassland vegetation were present in the seed bank, seed rain and vegetation of the other habitats. 4. The seed banks of SNGs and the seed rain of the FAFs were generally better predicted by the surrounding above-ground vegetation than were the other habitat types. The seed rain of the grazed communities was most similar to the vegetation in the FAFs, while the seed banks of the abandoned grasslands most resembled the vegetation in SNGs. 5. Gap availability and seed input could be limiting the colonisation of target species in FAFs, while remnant populations in the seed bank and the presence of grassland specialists in the above-ground vegetation indicate that abandoned grasslands and mid-field islets could be valuable sources of future diversity in the landscape after restoration. 6. Synthesis and applications. SNG communities are able to form seed banks which survive land-use change, but their seed rain does not reflect their above-ground communities. It is important that grassland plants set seed. By connecting existing grasslands with restoration targets, increased disturbance in the target habitats would allow for colonisation via the seed bank or seed rain, while decreased grazing intensity would benefit seed production in the source grasslands. Otherwise, landscape-wide propagule availability might increase with a more varied timing and intensity of management.
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Faktory určující rozšíření druhů suchých trávníků / Factors determining distribution of species in dry grasslandsPrůchová, Dana January 2010 (has links)
Factors determining distribution of species in semi-natural grasslands Survival and colonization of plant species in fragmented landscapes are topic of many recent studies. Most of them deal with one or just a few species or with overall species diversity. There are also a lot of studies devoted to the effect of abiotic characteristics and other parameters of fragmented habitat patches. Studies that would enable to evaluate behaviour of a large number of individual species are still relatively rare, especially in case of grassland species. Comparison of species traits in conjunction with the knowledge of type of historical land use and abiotic requirements of species can be a key to understanding of current species dispersal and their regional dynamic in fragmented landscape. This method of prediction of species dispersal can be a good implement for landscape planning and conservation of species and also their habitats. Goal of my thesis was to determine which traits of species influence response of species on land-use history in fragmented habitat of dry grasslands. I tried to use effect of land-use history without effect of environmental factors on species composition in phytosociological relevés. Then I tried to explain the reaction of species through their traits. I focused partially on traits...
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Effects of Agricultural Land-use on Forest Development, Herb Community Composition and Spatial DynamicsHolmes, Marion Andrews January 2017 (has links)
No description available.
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Assessing the Impacts of Balsam Woolly Adelgid (Adelges Piceae Ratz.) and Anthropogenic Disturbance on the Stand Structure and Mortality of Fraser Fir (Abies Fraseri (Pursh) Poir.) in the Black Mountains, North CarolinaMcManamay, Rachel Harris 04 June 2009 (has links)
Over the past several decades, naturally occurring populations of Fraser fir (Abies fraseri) in the Black Mountains of North Carolina have been heavily impacted by both direct and indirect anthropogenic disturbances, including logging and logging- associated fires, and high mortality rates due to the introduction of the exotic insect, balsam woolly adelgid (BWA) (Adelges piceae). The decline in Fraser fir is particularly concern because it serves as a foundation species within the spruce-fir forests of the Southern Appalachian Mountains. Our objectives for this research were to 1) use current stand structure to infer whether Fraser fir trees are experiencing a cycle of regeneration-mortality that will lead to eventual decline of the population, 2) determine what role, if any, the site-specific geographic variables of slope, elevation, aspect, and land use history have on stand structure, mortality, and BWA infestation level, and 3) analyze repeat aerial photography to examine broad trends of spruce-fir forest cover change caused by anthropogenic disturbance and the BWA. In order to understand stand structure, mortality, and infestation levels, we conducted detailed field surveys of Fraser fir trees throughout the Black Mountains using 44, fixed-radius circular sampling plots. These plots were placed throughout a series of aspects, elevations, and disturbance types in order to understand geographic variability among these variables. An analysis of 4 repeat aerial photographs and corroborating ground photographs revealed broad spatio-temporal trends of spruce-fir regeneration and mortality from 1954 to 2006. Our results indicate that Fraser fir stands at higher elevations are currently in a state of recovery; whereas stands at lower elevations appear to be more susceptible to BWA-induced mortality. Changes in forest cover area from 1954 to 2006 were influenced greatly by direct and indirect anthropogenic disturbance. Our results call attention to the significant impact that direct and indirect anthropogenic disturbance has had on Fraser fir stand structure, but also provide evidence for the ability of an imperiled ecosystem to recover from high rates of insect caused mortality. / Master of Science
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Long-term forest carbon storage and structural development as influenced by land-use history and reforestation approachUrbano, Andrea Rose 01 January 2016 (has links)
Temperate forests are an important carbon sink, yet there is uncertainty regarding land-use history effects on biomass accumulation and carbon storage potential in secondary forests. Understanding long-term biomass dynamics is important for managing forests as carbon sinks and for co-benefits such as watershed protection and biodiversity. However there are many unanswered questions regarding these dynamics in northeastern U.S. forests: How have secondary forests of the U.S. Northeast recovered post nineteenth century agricultural abandonment? How has the region's extensive land-use history influenced long-term structural development and aboveground carbon storage? To answer these questions, we employed a longitudinal study based on twelve years of empirical data (2001-2013) from the Marsh-Billings-Rockefeller (MBR) National Historical Park in Woodstock, VT. MBR Park was the first parcel of land to actively be reforested in the eastern U.S., and as such, its diverse forest mosaic reflects a history of alternate reforestation approaches and varied successional trajectories indicative of secondary forest recovery occurring across the broader northeastern forest landscape. We also used 150 years of documentary data from park management records. This research evaluates the effects of reforestation approaches (planting vs. natural regeneration), management regimes (long-term low-to-intermediate harvest intensities at varied harvest frequencies), and stand development pathways on biomass outcomes. We generated biometrics representative of stand structural complexity, including the H' structural diversity index, and aboveground biomass (live trees, snags, and downed coarse woody debris pools) estimates. Multivariate analyses evaluated the predictive strength of reforestation approach, management history, and site characteristics relative to aboveground carbon pools and stand structural complexity.
Classification and Regression Tree (CART) analysis ranked reforestation approach (plantation or natural regeneration) as the strongest predictor of long-term mean total aboveground carbon storage, while harvest frequency, and stand age were selected as secondary variables. CART ranked forest percent conifer (a metric closely associated with reforestation approach) as the strongest predictor of H' index, while harvest intensity, and harvest frequency were selected as secondary variables. Increases in harvest intensity can significantly reduce aboveground carbon storage. Our results suggest that a variety of long-term recovery pathways converge on high levels of aboveground carbon storage, including both conifer plantations and naturally regenerated hardwood stands, but choice of silvicultural management approach can dramatically alter those trajectories. Importantly, total aboveground biomass (i.e., carbon) co-varied with H' (r2 = 0.25), and thus, our dataset showed a positive relationship between forest carbon storage and structural complexity, supporting the concept of multifunctional forestry emphasizing late-successional habitats.
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Restauração de florestas tropicais em paisagens rurais: a influência do solo e cobertura florestal adjacente / Tropical forest restoration in rural landscapes: the influence of soil and adjacent forest coverageToledo, Renato Miazaki de 03 April 2017 (has links)
A restauração ecológica tem sido requisitada a para proteção de biodiversidade e serviços ecossistêmicos. Este desafio é enfrentado com suporte de grandes avanços de ordem teórica e prática, bem como incentivos financeiros e políticas específicas. No entanto, ainda restam incertezas quanto aos fatores que influenciam a trajetória da restauração de florestas tropicais, comprometendo a eficiência no uso de recursos limitados. Visando contribuir para o desenvolvimento metodológico da restauração florestal, e favorecer a identificação de metas de restauração adequadas, estudamos o efeito de características do solo e do contexto de paisagem na restauração de Mata Atlântica, buscando respostas para três questões: Como as áreas disponíveis para restauração se estão distribuídas com relação ao gradiente de degradação, em uma região amplamente antropizada? Qual a importância de características do solo e da cobertura florestal no processo de recuperação? E qual é o efeito da idade de fragmentos adjacentes na regeneração que se estabele em restaurações florestais? Utilizando bases de dados geográficos e estatísticas de terras agrícolas, observamos que os projetos de restauração tendem a se estabelecer sobre paisagens altamente degradadas. Combinando informações de sensoriamento remoto, com a caracterização de solo e da vegetação, em áreas abrangidas pelo mesmo programa de restauração florestal, verificamos que a recuperação de biomassa é afetada pela granulometria, pela cobertura do florestal, e pela interação entre granulometria e composição química dos solos. Também verificamos que a idade da cobertura florestal adjacente afeta a frequência de diferentes atributos. Nossos resultados corroboram a necessidade de avaliação em escala detalhada para a previsão dos resultados da restauração, e sugerem aprimoramentos metodológicos. Considerando que, em paisagens rurais, a adjacência à florestas maduras e a disponibilidade de solos conservados tendem a ser recursos mais raros, políticas de restauração de Mata Atlântica devem prever metas alternativas para as condições mais adversas, e técnicas para melhoria de condições do solo e conservação de remanescentes para possibilitar a recuperação de florestas tropicais em áreas adequadas / Ecological restoration is addressing concerns surrounding threats to ecosystem services and biodiversity. Support for this endeavor comes from substantial conceptual and practical advances, and policy initiatives and monetary incentives. Still, it remains unclear what are the main factors influencing tropical forest restoration. This lack of knowledge can compromise the willingness to restore and waste limited resources. To improve the knowledge base and aid identification of appropriate restoration targets, we studied the effect of soil and landscape context on tropical forest restoration, focusing in three main questions. We first asked: How the potential land supply for restoration is spatially distributed in the range of disturbance contexts of a highly degraded tropical region? Secondly, we asked: How important are soil properties and forest adjacency for biomass uptake and community assembly during early tropical forest restoration? And at last: What is the effect of the age of adjacent forests patches on the forest regeneration established in restoration sites? Using georeferenced databases and rural lands statistics, we observed that forest restoration is likely to be located within highly degraded landscapes. Combining remote sensing, with soil and vegetation survey undertaken in forest restoration sites that were implemented by the same program, we found that biomass recovery is affected by soil texture, surrounding forest coverage and the interaction between soil texture and soil chemical composition. We also found that the age of surrounding forest coverage affected the regenerating plant community, influencing species groups relative density, as related to seed dispersal syndrome, seed size and habitat specialization. Our results corroborate the need for fine scale evaluations to predict restoration outcomes, and anticipate methodological refinement. Given projections for decreasing presence of old-growth forests and increasing soil degradation in tropical rural landscapes, restoration policies likely need to consider alternative restoration targets for adverse conditions, coupled with improving soil conditions and protecting forest remnants to allow moist tropical forest recovery in appropriate areas
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German immigrants in Dubois County, Indiana, and the temperance movement of the 1850sHoffman, Aaron January 1997 (has links)
In the 1850s, many of Indiana's native-born Protestant population perceived the traditions and customs of German immigrants, specifically those concerning drinking alcoholic beverages and beer, as a threat to their "American way of life." They believed that the Germans' public drinking habits and behavior were the source of social problems causing instability and disorder prevalent in many of their communities. Although these problems were caused by Indiana's rapid industrialization and urbanization, older-stock Hoosiers blamed them on the readily identifiable immigrants. During the 1850s, temperance advocates in Indiana sought to force the German immigrants to conform to native-born Anglo-American culture to solve these problems of societal order and control. The temperance movement in Indiana was a fight to impose American cultural values on immigrants. Though temperance was a powerful social and political force in Indiana in the 1850s, it could not alter the tight-knit German Catholic community of Dubois County.The numerical strength of the German community and their strong opposition to assimilation hindered the temperance movement in Dubois County. The prominent role of the local Catholic Church and the Germans' common ethnic and cultural identity were two main factors in keeping temperance out of the county. Other significant factors were the permanent nature of the Germanimmigrants' settlement, the rural isolation of the county, the domination of the local Democratic party, and the prominence of beer in the German-Americans' culture.This study is historically important for several reasons. First, the reaction of this specific community to the antebellum temperance campaign provides a more complete understanding of how German immigrants in Indiana and the Midwest dealt with the problems of assimilation. Second, by focusing on a rural area, the German reaction to the issues of assimilation and temperance can be identified and examined independent of the urban problems of industrialization, overcrowding, and unemployment. Finally, it also constitutes the only known interpretation of the Indiana temperance movement from the perspective of those it most affected: the immigrants themselves. / Department of History
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Land use history promotes shifts in composition and increases the functional vulnerability of urban forestsPyles, Marcela Venelli 21 February 2018 (has links)
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Previous issue date: 2018-02-21 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A urbanização está transformando rapidamente nosso mundo e ameaçando a manutenção das funções do ecossistema, como biodiversidade e produção primária. Este estudo teve como objetivo compreender como diferentes histórias de uso da terra afetam a composição funcional e a diversidade das florestas urbanas e quão funcionalmente vulneráveis são essas florestas a futuros distúrbios. Utilizamos dados de nove florestas urbanas com diferentes históricos de uso da terra (HUT), agrupadas em três categorias de intensidade com três florestas em cada: desnudamento do solo (alta intensidade de HUT), cultivo (intensidade média de HUT) e sem histórico de uso da terra (baixa intensidade de HUT) e de três florestas maduras não urbanas (controle), para fins de comparação, todas situadas na Floresta Atlântica Brasileira. Abordamos duas questões: (i) em que medida as florestas urbanas com diferentes históricos de uso da terra diferem na composição e diversidade funcional e (ii) qual é a consequência do histórico de uso da terra na resistência e resiliência funcional das florestas urbanas? A primeira pergunta foi respondida através da categorização de espécies em grupos funcionais e pelos índices de riqueza funcional e dispersão; e a segunda através de uma análise de resistência, baseada em redundância funcional, e uma análise de resiliência, baseada na diversidade de resposta de espécies. Como prevemos, as florestas urbanas mostraram alterações na composição funcional, independente do histórico de uso. No entanto, efeitos negativos sobre a quantidade e diversidade funcional foram apenas encontrados em florestas com uso prévio da terra mais intenso (desnudamento do solo e cultivo). Apenas as florestas urbanas com histórico de uso da terra tiveram reduções significativas na redundância funcional e na diversidade de respostas das espécies. Surpreendentemente, as florestas urbanas sem histórico de uso da terra são capazes de manter altos níveis de diversidade e segurança funcional, semelhantes aos encontrados nas florestas não urbanas. Concluímos que, embora as florestas urbanas ainda possam servir como reservatórios de diversidade funcional e apresentar alguma segurança no fornecimento de suas funções diante de futuros distúrbios, a intensidade o uso prévio da terra é determinante para a redução, homogeneização e vulnerabilidade funcional dessas florestas. / Urbanisation is rapidly transforming our world and threatening the maintenance of ecosystem functions as biodiversity and primary production. This study aimed to understand how different land-use histories affect functional composition and diversity of urban forests and how functionally vulnerable are these forests to future disturbances. We used data from nine urban forests with different land-use histories (LUH) grouped in three intensity categories with three forests in each: soil denudation (high intensity LUH), cropland (medium intensity LUH) and without land use history (low intensity LUH) and from three non-urban mature forests (control), for comparison purposes, all situated in the Brazilian Atlantic forest. We addressed two questions: (i) to what extent do urban forests with different land-use histories differ in functional composition and diversity metrics?; and (ii) how functionally vulnerable are these forests to future disturbances? The first was answered from the species categorization into functional groups and by the functional richness and dispersion indices; and the second through a resistance analysis based on functional redundancy and a resilience analysis based on species response diversity. As we predict, urban forests showed differences in functional composition, regardless of the land use history. However, negative effects on the amount and diversity of functions were only related to the more intense previous land use (cropland and denudation LUH). Only urban forests with some land use history had significant reductions in functional redundancy and species response diversity. Surprisingly, urban forests without land use history are able to maintain high levels of functional diversity and safety, similar to those found in nonurban forests. We conclude that, although urban forests can still serve as reservoirs of functional diversity and may present some safety in the provision of their functions in the face of future disturbances, the intensity of land use history is determinant for the functional reduction, homogenization and vulnerability of these urban forests.
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