O crescimento populacional humano e o consumismo exacerbado têm elevado as demandas na produção de alimentos e gerado uma intensificação rural, se tornando um dos principais direcionadores do declínio da biodiversidade. O manejo de gado está se intensificando e expandindo, muitas vezes às custas da derrubada de áreas florestais. Mas manejar o gado em campos naturais pode ser uma estratégia para a conservação desses ecossistemas. Os métodos de manejo determinam as comunidades de campos, de forma que baixa pressão de pastejo parece promissor para a conservação. De modo geral, direcionadores ambientais tendem a gerar padrões na diversidade em grande escala, enquanto a competição contribui para determinar a coexistência local. Contudo, os processos de montagem das comunidades podem diferir entre regiões. Assim, especialmente filtros ambientais e interações bióticas atuam dinamicamente e direcionam o padrão da comunidade. As espécies que persistem se diferenciam especialmente em grupos alimentares conforme os recursos disponíveis, e competem dentro desses grupos conforme os nichos dos consumidores se sobrepõem. Além disso, as características morfológicas individuais podem facilitar ou restringir sua habilidade em persistir em um ambiente, ao passo que mediam os processos ecossistêmicos. Os insetos representam o maior componente da biodiversidade em ecossistemas terrestres, e são considerados sensíveis às condições ambientais. Coleoptera é a ordem de insetos com maior riqueza em espécies, que abrange uma larga extensão de grupos funcionais, e são sensíveis às variações ambientais. O objetivo desta Tese foi testar se as comunidades de Coleoptera refletem diferenças nas pressões pastoris exercidas pelo gado. Essa Tese revela resultados inéditos para cada uma das abordagens empregadas, especialmente considerando a escala regional do experimento. A diversidade de besouros residentes do solo mostrou um padrão geral com relação positiva ao pastejo enquanto os residentes da vegetação demonstraram uma relação negativa ao pastejo. Os herbívoros residentes da vegetação são bastante sensíveis ao pastejo do gado, e declinam com o aumento da intensidade, enquanto que os predadores residentes da vegetação parecem responder positivamente a uma vegetação mais arbustiva do que de gramíneas. Além disso, parece que, potencialmente, os besouros também respondem com seus atributos morfológicos às diferenças na estrutura da vegetação conforme a intensidade de pastejo. O pastejo de baixa intensidade parece uma boa opção para beneficiar a conservação da biodiversidade. Contudo, manejar campos naturais com apenas uma técnica não permite conservar igualmente os besouros campestres. / Human population growth and exacerbated consumerism have raised the demands on food production and generated rural intensification, becoming one of the main drivers of biodiversity decline. Livestock management is intensifying and expanding, often at the cost of clearing forested areas. However, managing livestock in natural grasslands may be a strategy for the conservation of these ecosystems. Management methods determines the communities in grasslands, so that low pressure grazing seems promising for conservation. In general, environmental drivers tend to generate diversity patterns at large scales, while competition contributes to determining local coexistence. However, the assembly processes of communities may differ between regions. Thus, environmental filters and biotic interactions, especially, act dynamically and direct the community pattern. Species may persist when different, especially according to feeding groups, and compete within these groups when consumer niches overlap. In addition, individual morphological traits may facilitate or restrict a species ability to persist in an environment, while at the same time mediating ecosystem processes. Insects represent the largest component of biodiversity in terrestrial ecosystems, and have been considered sensitive to environmental conditions. Coleoptera is the insect order with the largest species richness, covering a wide range of functional groups, and are sensitive to environmental variations. The aim of this thesis was to test whether Coleoptera assemblages reflect differences in the pastoral pressures exerted by livestock. Ground-dwelling beetle diversity showed a general pattern of positive relationship with grazing while grass-dwellers showed a negative relationship with grazing. Grass-dweller herbivores are quite sensitive to livestock effects, and decline with increasing grazing intensity, while grass-dweller predators appear to respond positively to scrubs rather than to grass vegetation. In addition, it seems that, potentially, beetles also respond with their morphological traits to differences in vegetation structure according to grazing intensity. Some of these results are unprecedented, especially considering the regional scale of the experiment. Low intensity grazing seems to be a good option to benefit biodiversity conservation. However, managing grasslands with a single technique would not provide grassland beetles conservation equally.

Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2018-05-21T16:23:31Z No. of bitstreams: 1 Ingo Hübel_.pdf: 3839162 bytes, checksum: 96ef72eff66abad33169ea566c1b3c53 (MD5) / Made available in DSpace on 2018-05-21T16:23:31Z (GMT). No. of bitstreams: 1 Ingo Hübel_.pdf: 3839162 bytes, checksum: 96ef72eff66abad33169ea566c1b3c53 (MD5) Previous issue date: 2009-05-29 / Aracruz Celulose S/A / A implantação de monoculturas de eucalipto é muito criticada e tratada como responsável pela degradação do solo e por importantes mudanças biológicas. No Rio Grande do Sul a conservação dos campos se limita basicamente às Áreas de Preservação Permanente – APP, que prevêem a preservação de uma faixa de 30 m de vegetação ciliar a partir dos cursos d’água e também de áreas de reserva legal. Este estudo investiga as possíveis mudanças na diversidade, composição e abundância de espécies vegetais campestres em função da proximidade com plantações de eucalipto. O estudo foi realizado na fazenda Formosa, situada no município de São Gabriel, RS. Foram escolhidas três áreas com interface entre monocultura de eucalipto e campo e três áreas de campo sem plantio de eucalipto (controle). Um total de 120 parcelas fixas de 1 m x 1 m foi aleatorizado em transecções lineares a 5 e 30 m a partir da borda do eucalipto e do limite da APP nas áreas controle. Com auxílio de um quadro gradeado de 10 em 10 cm foi feito o levantamento da cobertura-abundância de todas as espécies vasculares presentes, além do levantamento de fatores de ambiente. No inventário foram encontradas 145 espécies vegetais campestres. A riqueza e diversidade de espécies apresentaram o mesmo padrão para as áreas com eucalipto, sendo que na monocultura a riqueza foi maior na borda e menor no interior em relação à APP adjacente, que apresentou riqueza intermediária e não diferiu entre si nas distâncias a partir da borda. Esse gradiente não é observado para áreas sem eucalipto. Em conjunto estes resultados sugerem um efeito da monocultura sobre a diversidade de espécies adjacente. A composição e abundância-cobertura de espécies variaram significativamente entre os ambientes avaliados. Fatores de ambiente como umidade relativa, compactação do solo e inclinação do terreno foram importantes na determinação da composição e abundância-cobertura de espécies nas APPs. Os resultados deste trabalho demonstram que apenas a manutenção de APPs com áreas de vegetação campestre não garante a manutenção da integridade biológica dos campos. / The establishment of monocultures of eucalyptus is criticized and regarded as responsible for soil degradation and significant biological changes. In Rio Grande do Sul, south Brazil, the conservation of grasslands is confined to areas of permanent preservation - APP's, defined by current legislation as the riparian vegetation extending 30 m from both sides of watercourses. This study investigates the possible changes induced by eucalyptus plantations on adjacent grassland APPs. The study was conducted in Formosa ranch, located in the municipality of São Gabriel, RS. Three areas with the interface between eucalyptus plantations and grassland APPs, and three other areas without eucalyptus plantations (control areas) were chosen for the study. A total of 120 1 m2 plots were randomized along linear transects established at 5 and 30 m from the edge of the APP both to the APP itself and towards the plantation interior (in areas with plantations) or towards grasslands outside APPs (in control areas). A grid of 10 by 10 cm was used to assess the cover-abundance of all vascular species present at each plot revealing a total of 145 plant species. The richness and diversity of species showed the same trend for areas with eucalyptus: inside plantations species richness was greater in the edge, while in the adjacent APP species richness did not present a clear distance gradient. Such a distinction between APPs and areas distant from APPs was not detected in control areas. In conjunction these results suggest a possible effect of the plantation upon the species richness of adjacent APPs. The composition and coverage-abundance varied significantly among the areas studied . Environmental factors such as soil humidity and compaction, and relief slope were important in determining the composition and abundance of species in APPs. This study shows that the maintenance of APPs do not suffice to preserve the integrity of grassland vegetation.

Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2015-06-01T14:26:00Z No. of bitstreams: 1 Daniele Uarte de Matos.pdf: 2364533 bytes, checksum: 3e59ca5ecf26f32227c6325e8bf168e2 (MD5) / Made available in DSpace on 2015-06-01T14:26:00Z (GMT). No. of bitstreams: 1 Daniele Uarte de Matos.pdf: 2364533 bytes, checksum: 3e59ca5ecf26f32227c6325e8bf168e2 (MD5) Previous issue date: 2012 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Mudanças históricas, socioeconômicas, culturais e naturais determinam, ao longo do tempo, mudanças também na escala de paisagem em todos os lugares do mundo. Essas alterações são dinâmicas, têm ocorrido em grandes proporções nas últimas décadas e o ser humano tem sido o maior responsável por essas perturbações na paisagem que podem ter consequências tanto em extensão espacial como em duração temporal. No nordeste do Rio Grande do Sul (RS), sul do Brasil, a paisagem tem sofrido muitas alterações desde o século XIX e hoje requer atenção especial para os ecossistemas campestres e florestais da região. O objetivo deste trabalho foi quantificar, descrever e avaliar as mudanças na paisagem do Nordeste do RS, e principalmente a dinâmica do mosaico entre ecossistemas florestais e campestres na região dos Campos de Cima da Serra (CCS) no Planalto das Araucárias, quanto ao uso do solo ao longo de um período de 21 anos. Imagens de Satélite Landsat 5 TM de 1984, 1994 e 2005 foram classificadas em seis classes de uso do solo das quais foram extraídas métricas de paisagem e o índice de umidade NDMI a fim de caracterizar a dinâmica da paisagem na região no período estudado. A área também foi classificada segundo regiões geoeconômicas que abrangem a região. A partir dos dados das regiões geoeconômicas, anos e as respectivas classes de uso do solo e áreas correspondentes, realizou-se uma Análise Log-linear. Para avaliar a variação do índice NDMI ao longo do tempo, realizou-se um Teste G, relacionando os 15 níveis de umidade gerados com as suas respectivas áreas em cada ano. Através de análise Log-linear relacionou-se as áreas representadas pelos níveis de umidade com os próprios níveis de umidade, anos e pluviosidade média dos 12 meses anteriores às imagens de satélite analisadas. Um mapa sobrepondo as áreas agrícolas sobre as áreas de campo classificadas conforme umidade foi feito a fim de visualizar a direção da expansão desta classe. A análise Log-linear mostrou que diferentes classes de uso do solo tiveram aumentos e contrações diferenciados em diferentes regiões geoeconômicas ao longo do tempo (χ2=89120,612, gl=40, p=0.0). O Teste G (χ2= 592875,970, gl=26, p=0,0) foi significativo, mostrando a variação das áreas úmidas ao longo do tempo. A análise Log-linear com os dados pluviométricos refletiu a variação das áreas correspondentes aos níveis de umidade ao longo do tempo (χ2= 4,421E+10, gl = 89, p=0,0). As áreas agrícolas expandiram-se preferencialmente sobre as áreas com os maiores níveis de umidade, conforme mapa confeccionado. O contraste entre áreas naturais e antrópicas aumentou, sendo que áreas agrícolas apresentaram grande crescimento e áreas de campo e floresta foram reduzidas, tornando-se mais fragmentadas. Os resultados mostraram que a região nordeste do RS sofreu grande impacto no uso e cobertura do solo no período estudado e que áreas úmidas de campo foram preferencialmente ocupadas na expansão agrícola. / Historical, socioeconomic, cultural and natural changes determine, over time, changes also at the landscape scale everywhere in the world. These changes are dynamic, have occurred in large numbers in recent decades and thehuman are largely responsible for these disturbances on the landscape that may have consequences both in spatial extent and duration of time. In northeastern Rio Grande do Sul (RS), southern Brazil, the landscape has undergone many changes since the century XIX and today special attention to the forest and grassland ecosystems of the region is required. The objective of this study was to quantify, describe and evaluate changes in the landscape of northeastern RS, and especially the dynamic mosaic of forest and grassland ecosystems in the region of Campos de Cima da Serra (CCS) in the Araucaria Plateau, on the use of soil over a period of 21 years. Satellite images of 1984, 1994 and 2005, obtained through Landsat 5 TM, were classified into six classes of land use. From these images landscape metrics and NDMI moisture index were extracted to characterize the dynamics of the landscape in the region during the studied period. The area was also classified according to geoeconomic regions covering the region. From the data of geoeconomic regions, years and the respective classes of land uses and related areas, a Log-linear analysis was performed. To evaluate the changes in the index NDMI over time, a G test was applied, listing the 15 levels of moisture generated in their respective areas for each year. Using a Log-linear analysis the relation between the areas represented by the moisture levels with their own levels of moisture, the years and the rainfall average of 12 months prior to satellite images analyzed was tested. A map overlaying agricultural and grassland areas according to the moisture level was done in order to visualize the direction of expansion of this class. The analysis showed that different classes of land uses increased and contractions were different in different geoeconomic regions over time (χ2 = 89120,612, df = 40, p = 0.0). Test G (χ2 = 592875,970, df = 26, p = 0.0) was significant, showing wetlands variation over time. Log-linear analysis rainfall interacted in areas corresponding to the variation of moisture levels over time (χ2 = 4,421E +10, df = 89, p = 0.0). The agricultural areas have expanded preferentially in the areas with the highest levels of humidity. The contrast between natural and anthropogenic areas increased, and agricultural areas presented great growth whereas field and forest areas reduced, becoming more fragmented. The results showed that the northeast region of the RS hads a major impact on land uses and cover over the studied period and that areas with more moisture were converted into agricultural expansion.

Studies in grassland management and ecology have always been challenging because of the large amount and great variation of the entities representing and affecting the system. Despite that, we were able to progress significantly in range experimentation in the Campos, in Southern Brazil. Along past thirty years, a large amount of data and information was generated, from vegetation production to components of intake. In an attempt to integrate the information available, seeking for a deeper understanding of the functioning of native grasslands, we propose adapting a mechanistic vegetation model, aggregated of a spatialized grazing component to create PampaGraze. This model was developed for temperate perennial grasslands, and was adapted and tested for subtropical, C4-dominated grasslands of the Campos of Southern Brazil (Chapter III). Despite the limited capacity of field data for validating, the model was able to relatively well simulate the trends in vegetation production along the year and seasons, while overpredicting herbage production during peak growing season. The structure of the model as it is did not allow for an accurate simulation slow-growing, tussock-forming species. Further, we developed and integrated a grazing model, based on a hybrid approach of the classical mechanistic equations of the prey model (STEPHENS & KREBS, 1986), and experimental data on foraging behaviour measured on native grasslands (Chapter IV). The model was very successful on predicting the components of intake, and responded well to variation of components in relation to changes in vegetation and to selectivity pressures, compared to available literature. Regardless of the limitations on the vegetation model, we were able to further explore the relationships of components of intake, identifying possible major limitations for herbage consumption, thus animal performance, in native grasslands. A significant progress was achieved with this thesis, but still long ways to go with this project. A list of suggestions for further developments can be found in Chapter V. We identified the emergent needs for field studies on parameters and morphogenesis, for improving predictions of the vegetation model, as well as structural points of the model that could be addressed for better representation of natural phenomena. This thesis is the first step towards a more detailed and reliable tool for studying and predicting the behaviour of vegetation dynamics and animal production in sub-tropical grasslands. This can allow us to explore relationships and scenarios beyond our experimental capacity, and investigate the connectivity of the system, as well as each mechanism separately. The stage has been set, awaiting further developments.

Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2015-05-04T12:59:49Z No. of bitstreams: 1 Leonardo Moreira.pdf: 1440108 bytes, checksum: de671eaa37968d8fdb3e5f647af88a48 (MD5) / Made available in DSpace on 2015-05-04T12:59:49Z (GMT). No. of bitstreams: 1 Leonardo Moreira.pdf: 1440108 bytes, checksum: de671eaa37968d8fdb3e5f647af88a48 (MD5) Previous issue date: 2013 / CNPQ – Conselho Nacional de Desenvolvimento Científico e Tecnológico / Iniciativas de conservação em paisagens agrícolas têm se tornado uma das prioridades na agenda de conservação de anfíbios, já que mudanças no uso da terra estão associadas com declínios globais. Nesta tese, eu procurei analisar os efeitos da fragmentação e intensificação agrícola na riqueza e composição de anfíbios anuros, em áreas úmidas do bioma Pampa no Rio Grande do Sul. A tese está dividida em três capítulos. No primeiro, eu avaliei diferenças em assembleias de anuros entre áreas naturais, arrozais orgânicos e arrozais não orgânicos. No segundo capítulo, eu investiguei os padrões de concorrência e alinhamento em assembleias associadas à áreas naturais e arrozais com diferentes idades de cultivo. No último capítulo, eu examinei a relação entre abundância de girinos e características do habitat em cinco escalas espaciais, na metade sul do Rio Grande do Sul. Considerando os três estudos, é possível concluir que ações de conservação focadas em anfíbios que utilizam áreas agrícolas requerem o manejo de diferentes elementos em múltiplas escalas espaciais. Diferentes espécies de anuros não respondem à mesma escala espacial ou a diferenças históricas entre as áreas. Portanto, determinar a extensão das respostas espécie-específicas é uma etapa urgente para alternativas de conservação viáveis, em paisagens agrícolas do bioma Pampa. / Conservation initiatives in agricultural landscapes have become one of the priorities on the conservation agenda of amphibians, because l and use changes are associated with global declines. In this thesis, I tried to analyze the effects of agricultural fragmentation and intensification on anuran species richness and composition, in et lands of Pampa biome in Rio Grande do Sul. The thesis has three chapters. In the first one, I evaluated differences in anuran assemblages across natural areas, organic rice fields, and non-organic rice fields. In the second chapter, I investigated species co-occurrence and nested ness patterns in assemblages associated to natural areas and rice fields with different crop ages. In the last chapter, I examined the relationship between tadpole abundance and habitat features at 5 spatial scales, in southern half of Rio Grande do Sul state. In general, I conclude that amphibian conservation actions in agricultural areas need the management of different elements at multiple spatial scales. Different anuran species do not all respond to the same spatial scale or to historic differences across the areas. Therefore, to determine the extent of species-specific responses are an urgent steep toward workable conservation alternatives across agricultural landscapes in Pampa biome.

This study examined the ant communities of several grasslands of the Australian Capital Territory (ACT) and their relevance to the pink-tailed legless lizard, Aprasia parapulchella (Pygopodidae). A. parapulchella is a fossorial species that shares burrows with, and eats the brood of, several grassland ant species. Foraging ants were collected from sites by pitfall trapping throughout one calendar year and comparisons of ant communities made between seasons and sites of differing vegetation structure. Competition between ant species for artificial nest sites and the effects of temperature on selection of nest site selection were also studied. The role that ants play in the distribution of A. parapulchella was investigated by (i) comparing ant faunas from several sites throughout the geographic range of the lizard, including sites in New South Wales and Victoria, (ii) performing feeding preference experiments with A. parapulchella, and (iii) investigating the seasonal nature of brood production and nest establishment by ants in ACT grasslands. Major findings were used to make recommendations to assist in the management, including rehabilitation, of A. parapulchella grassland sites. Low insolation appears to significantly affect the ant species composition of grassland sites in the ACT relative to other Australian vegetation types. In the ACT grassland sites, large species of the Dominant Dolichoderinae functional group were absent, or present only in very low numbers. The communities were species-poor relative to other Australian studies with only 60 species being recorded across all sites studied, with no more than 21 species recorded at any site on any sampling occasion. Whilst ant species community structure was highly variable between seasons and sites, more than 95% of ants were from the three functional groups, Dominant Dolichoderinae, Generalized Myrmicinae and Opportunists. The communities were numerically dominated throughout the year by the ubiquitous species groups Iridomyrmex 'rufoniger' and Rhytidoponera 'metallica'. Almost all taxa increased in foraging abundance during summer months and Pheidole spp., Monomorium spp., Crematogaster sp. Paratrechina sp. and Notoncus ectalomoides were occasionally locally abundant. There were no significant relationships between ant and vegetation community structures, but Solenopsis sp. showed an alliance with sites that had a high abundance of Themeda australis (kangaroo grass), whilst Crematogaster sp. and Paratrechina sp. are potential bioindicators of disturbance from grazing or pasture improvement. Iridomyrmex 'rufoniger' were the numerically dominant foraging ants, making up 50% of all captures, but they held only 80% of their nest sites when faced with competition from other species. R. 'metallica' and Pheidole spp. on the other hand, gained 80% more nests than they lost to other taxa. I. 'rufoniger' and R. 'metallica' both preferred nest sites with warmer temperature regimes when given the choice, and this assisted them to tend brood throughout the year. All ant species in ACT grasslands had summer peaks in brood production. Most nests were inactive throughout the cooler months and nest founding was predominantly between September and November. The common species, Iridomyrmex spp., Paratrechina sp. and R. 'metallica' held winged reproductives in their nests from April and all ant taxa had released all alates by mid- November. Although there were differences in ant community structure throughout the range of A. parapulchella, the ubiquitous R. 'metallica' and I. 'rufoniger' were always abundant, whilst again, Dominant Dolichoderinae and associated subordinate taxa were absent or present only in relatively low numbers. The lizards consumed brood from all the common ant species in ACT grasslands and showed preference for consuming brood of, and living with, small Iridomyrmex spp. The range of the small Iridomyrmex spp. preferred by A. parapulchella extends far beyond that of the lizard. Its distribution is apparently not restricted by the range of its ant prey species. For rehabilitation of A. parapulchella sites in the ACT, it is recommended that a significant ground cover of native grasses is established to ensure the low abundance of large and territorial ants from the Dominant Dolichoderinae functional group. Along with a high abundance of shallow surface rocks, this will ensure the establishment of ant communities that are numerically dominated by small Iridomyrmex spp., which are preferred by A. parapulchella for homesite sharing and as a food source.

Although semi-natural grasslands in Europe are declining there is often a time delay in the local extinction of grassland species due to development of remnant populations, i.e., populations with an extended persistence despite a negative growth rate. The objectives of this study were to examine the occurrence of remnant populations after abandonment of semi-natural grasslands and to examine functional traits of plants associated with the development of remnant populations. We surveyed six managed semi-natural grasslands and 20 former semi-natural grasslands where management ceased 60-100 years ago, and assessed species response to abandonment, assuming a space-for-time substitution. The response of species was related to nine traits representing life cycle, clonality, leaf traits, seed dispersal and seed mass. Of the 67 species for which data allowed analysis, 44 species declined after grassland abandonment but still occurred at the sites, probably as remnant populations. Five traits were associated with the response to abandonment. The declining but still occurring species were characterized by high plant height, a perennial life form, possession of a perennial bud bank, high clonal ability, and lack of dispersal attributes promoting long-distance dispersal. Traits allowing plants to maintain populations by utilizing only a part of their life cycle, such as clonal propagation, are most important for the capacity to develop remnant populations and delay local extinction. A considerable fraction of the species inhabiting semi-natural grasslands maintain what is most likely remnant populations after more than 60 years of spontaneous succession from managed semi-natural grasslands to forest. / <p>authorCount :3</p>

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