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Climate changes and associated glacial and interglacial cycles during the Quaternary strongly influenced the evolutionary history of countless number of species. Subtropical highland grasslands (SHG) in southern South America constitute a distinct vegetation type with high diversity and endemism rates. The most recent common ancestor of the genus Petunia (Solanaceae) originated in lowland grasslands, and some lineages secondarily migrated to SHG. Here, we describe the evolutionary history of an SHG species, P. altiplana, distributed throughout a wide area in a river-fragmented landscape. We used plastid and nuclear markers to evaluate the role of the Pelotas River and Quaternary climate cycles over the genetic structure and historical demography of this species based on a phylogeographical approach. We found moderate population expansions during the last 25 kyr, with a more recent (c. 1.6 kya) divergence between two groups of populations from opposite river margins, possibly caused by the expansion of the Araucaria Forest along the river valley, effectively isolating distinct grassland patches.

Active manipulation of disturbances such as fire and grazing is often necessary to maintain or enhance biodiversity values in grasslands. However in many instances information is lacking on the disturbance regimes most likely to achieve conservation aims. This paper provides an overview of the effects of fire and grazing in Tasmanian highland grasslands, and the implications of these for conservation management of this vegetation. In Tasmania, highland grassland is defined as occurring above 600 m above sea level. The vegetation is typically dominated by species of Poa. Highland grassland is grazed by a suite of native herbivores and has a history of stock grazing, which continues at some sites of high biodiversity value. There is evidence that Indigenous Tasmanians regularly burnt highland grasslands and that Indigenous burning was instrumental in maintaining grassland at sites that otherwise would be forest. For highland grasslands below 1000 m asl, a reduction in the biomass of dominant grasses through disturbance is necessary in order to maintain plant species diversity. The use of periodic fire, together with native grazing, is likely to be beneficial in this regard. The combination of fire and grazing is also likely to prevent woody plant invasion and maintain vegetation structural heterogeneity. The near ubiquity of native grazing species means there is no ecological imperative for stock grazing. Low productivity of grasslands occurring above 1000 m means that competitive exclusion of interstitial species by grasses is unlikely and therefore active application of disturbance as a management tool will rarely, if ever be necessary. Disturbance management should be accompanied by a well-designed monitoring program and regular review of the management strategy

In the Andean Cordillera, natural grasslands above 2500 m are used for livestock grazing. Few studies on the effects of foraging natural vegetation have been conducted in the northern Argentinean Andes, although this activity is frequently considered to be involved in the dragging of large amounts of sediment and in soil erosion after summer rainfall. The present study aims to identify and describe floristic composition in main vegetation units, and the potential and susceptibility of these units to foraging within a small catchment in the Andes of northwestern Argentina. Vegetation was sampled for total cover, cover per species, altitude, exposure, slope, and foraging pressure. Data are classified and ordered through multivariate analysis. Species are also classified according to life form (shrubby, gramineous/graminoids, and herbaceous) and palatability. Variance Analysis was applied to detect significant differences among vegetation units. In the study area, differences in the floristic compos...

It has been suggested that natural fires in these grasslands would have occurred as infrequently as every four or more years. Currently, the majority of the system is managed by livestock farmers who burn their land annually at the onset of the rainy season (early in the austral summer).

Os campos de altitude do sudeste da América do Sul possuem uma alta diversidade de plantas endêmicas. Estudos apontam para uma complexa história biogeográfica na formação da composição florística dessa região. O clima subtropical e as variações altitudinais, levam à existência de habitats heterogêneos e à presença de várias espécies únicas. A compreensão dos processos de diversificação em áreas específicas, altamente diversas, ao longo do tempo, permite inferir sobre os padrões históricos que influenciam na formação da flora e da paisagem. Assim, este trabalho teve como objetivo acrescer conhecimento sobre a dinâmica evolutiva das formações de altitude, como um primeiro passo para entender sua origem, elucidando processos históricos responsáveis pelo estabelecimento da flora atual. Para tanto, foram destacados táxons que apresentam alta representatividade, tanto nos Campos de Altitude brasileiros, quanto em áreas relacionadas ao foco do estudo: os Pampas, o Cerrado senso lato, a região andina e as regiões de altitude no sul da América do Norte e América Central (Mesoamérica). Foram realizadas análises filogenéticas datadas independentes, juntamente com análises de Dispersão, Extinção e Cladogênese (DEC) e mapeamento estocástico biogeográfico (BSM) para obter estimativas de área ancestral, assim como número relativo de eventos de dispersão e a época em que estes ocorreram. Os resultados mostram que existem conexões pretéritas entre as áreas e foram nos últimos 7 milhões de anos que a maioria destes eventos de dispersão ocorreram. Radiações nos Campos de Altitude do Brasil são majoritariamente recentes e a maior interação se deu com os Pampas. Além disso, o grande número de radiações locais indica que a área prioriza eventos de diversificação in situ em detrimento de eventos de intercâmbio com as demais áreas, especialmente as áreas mais distantes. The southeast highland grasslands of South America present high biodiversity and many endemic plants. Several studies point that a complex biogeographic history is related to the floristic composition of this region. Biotic and abiotic factors influenced the diversification and distribution plants patterns over time. The tropical-subtropical climate of this region shows a latitudinal gradient that, added to the variations in altitude, provides the existence of heterogeneous habitats and several exclusive species. In this thesis, our aim was to understand the diversification processes over time in plant lineages that present high diversity in the highland grasslands, allowing us to infer about the historical patterns that led to the formation of the current landscape in this region. Thus, we updated and taxonomically review the plant species endemism list from the highland grasslands in southern Brazil through extensive research based on taxonomic studies, protologues, and herbarium specimens, comprising a vast database with historical and current information. We performed molecular phylogenetic analyzes, with estimates of the time of divergence and distribution of four taxa that have high representativeness both in the highland grasslands and in the other areas related to the study - Pampa Biome, Cerrado sensu lato, the Andean region and grassland regions in southern North and Central America (Mesoamerica). These approaches allowed us to improve our understanding of the taxonomy, phylogeny, and evolutionary historical biogeography of the highland grasslands of South America. As a result, we updated the list of endemism in Brazil's subtropical highland grassland to 273 taxa (23.5% of its flora), representing 40 families and 117 genera, highlighting 57 taxa reported as endemic to this region for the first time. Moreover, we showed the existence of past connections between the highland grassland and the Andes region, although most dispersal events involving the highland grasslands were concentrated in the last seven million years. The Pampa appears as the area that currently shares more taxa with the highland grasslands, and the large number of local radiation observed for the studied area indicates the events of diversification in situ as more frequent than events of vicariance with more distant areas.

Understanding the botanical composition of herbivores&rsquo, diets and their nutritional quality is an important question in the development of sustainable strategies for the management of natural resources. In Chilean highland vicu&ntilde, a-grazed grasslands, there is little information in this regard and, therefore, this study aimed to determine the year-round profile of the diet&rsquo, s botanical composition and quality. In highland grasslands, on an area of 21.9 ha, continuously grazed for 3.06 VU/ha/year (18&deg, 03&prime, S, 69&deg, 13&prime, W, 4425 m.o.s.l), twelve feces piles were sampled monthly and were analyzed through microhistology, and the nitrogen concentration [NF, OM basis] was determined. The botanical composition, diversity (J) and selectivity index (Ei) of the main species were estimated. Diets were composed of dry&ndash, grassland grasses (37.7%), wet&ndash, grassland grasses (36.6%), graminoids (14.3%) and forbs (10.2%). The diet diversity ranged from 0.79 (dry&ndash, winter) to 0.87 (wet&ndash, summer). The main dominant grassland species obtained negative Ei values. The annual mean value of [NF] was estimated as 1.82%, with a higher value in summer months (2.21%), which coincides with the physiological states of higher nutritional demand. The vicu&ntilde, as behave like generalist ungulates, having a high degree of selectivity towards grass species, which mostly fulfill a nutritional role in subsistence and a functional role in survival, applying foraging strategies that allow them to obtain a better quality diet during the season of greatest nutritional demand.

Presentamos el primer registro de Batrachochytrium dendrobatidis infectando poblaciones amenazadas del sapito de panza roja de Tandil (Melanophryniscus aff. montevidensis). Obtuvimos muestras de hisopados de piel de 32 individuos cuyos resultados indicaron una prevalencia del 35.5% y niveles de infección que variaron entre 0.34-915 equivalentes genómicos de Batrachochytrium dendrobatidis. Este hallazgo representa una nueva amenaza que, conjuntamente con la alta fragmentación del hábitat, podría estar afectando la viabilidad de las poblaciones estudiadas. We present the first record of Batrachochytrium dendrobatidis (Bd) infecting endangered populations of the Tandilean Red-belly toad (Melanophryniscus aff. montevidensis). We obtained skin swab samples of 32 individuals. The prevalence was 35.5% and the infection levels varied between 0.34 and 915 Bd-genomic equivalents. This finding represents a new threat that could be affecting, in conjunction with the high habitat fragmentation, the viability of the studied populations. Fil: Agostini, Maria Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina Fil: Cortelezzi, Agustina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto Multidisciplinario de Ecosistemas y Desarrollo Sustentable; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Berkunsky, Igor. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto Multidisciplinario de Ecosistemas y Desarrollo Sustentable; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Soler, Gabriela. Instituto Superior de Formación Docente y Técnica Nº 10 “Dr. Osvaldo Zarini”; Argentina Fil: Burrowes, Patricia. Universidad de Puerto Rico; Puerto Rico

Made available in DSpace on 2016-07-19T13:51:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-11-01. Added 1 bitstream(s) on 2016-07-19T14:08:06Z : No. of bitstreams: 1 S1519-69842003000400010.pdf: 1463760 bytes, checksum: 9ab3d85dbeec4c05d7ab32bb08b2ab33 (MD5) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Doze segmentos de riachos foram amostrados quatro vezes em 1998-1999 (uma amostragem em cada estação) na bacia de drenagem do alto rio São Francisco (19o45’-21o25’S, 49o05’-51o30’W), situado no Parque Nacional da Serra da Canastra, em altitudes de 1.175 a 1.400 m. O levantamento das macroalgas resultou em 30 espécies, com predominância de Cyanophyta (12 espécies = 40%) e Chlorophyta (11 espécies = 36,5%) e menor proporção de Rhodophyta (sete espécies = 23,5%). Duas espécies, Klebsormidium rivulare (Chlorophyta) e Kyliniella latvica (Rhodophyta), constituem novos registros para o Brasil. Capsosira sp. e Stigonema sp. (Cyanophyta) e o estágio “Chantransia” de Batrachospermum (Rhodophyta) foram as macroalgas mais amplamente distribuídas, ocorrendo em 6 pontos de amostragem, enquanto 11 espécies foram encontradas em apenas um ponto. As proporções de tipos morfológicos de macroalgas foram as seguintes: emaranhado de filamentos (33%), filamentos livres (27%), filamentos gelatinosos (7%), crostas (7%) e tufos e colônias gelatinosas (3%). A flora teve poucas espécies em comum (4%-8%) com macroalgas lóticas de outras regiões brasileiras. As comunidades de macroalgas mostraram-se ricas, com valores de riqueza de espécies próximos aos mais altos anteriormente reportados. Os padrões típicos para comunidades de macroalgas lóticas de distribuição em mosaico e dominância de poucas espécies também foram encontrados nessa bacia. Entretanto, as variáveis ambientais mais influentes sobre a distribuição de macroalgas neste estudo (substrato rochoso, baixos valores de pH e altos de DQO, cor da água e velocidade da correnteza) foram essencialmente as mesmas que melhor descreveram as características limnológicas desse ecossistema lótico. Além disso, essa combinação de variáveis foi nitidamente diferente dos resultados de estudos anteriores em outros ecossistemas lóticos brasileiros. Twelve stream segments were sampled four times in 1998-1999 (one sampling per season) in the drainage basin of the upper São Francisco River (19 masculine 45'-21 masculine 25'S, 49 masculine 05'-51 masculine 30'W), situated in Serra da Canastra National Park, at altitudes ranging from 1,175 to 1,400 m. The macroalgae survey resulted in 30 species, with a predominance of Cyanophyta (12 species = 40%) and Chlorophyta (11 species = 36.5%) and a lower proportion of Rhodophyta (seven species = 23.5%). Two species, Klebsormidium rivulare (Chlorophyta) and Kyliniella latvica (Rhodophyta), were new records for Brazil. Capsosira sp. and Stigonema sp. (Cyanophyta) and the Chantransia stage of Batrachospermum (Rhodophyta) were the most widespread macroalgae, occurring in six sampling sites, whereas 11 species were found at only one site. The proportion of macroalgal morphological types were as follows: mats (33%), free filaments (27%), gelatinous filaments (27%), crusts (7%), tufts (3%), and gelatinous colonies (3%). The flora revealed few species in common (4%-8%) with stream macroalgae from other Brazilian regions. The macroalgal communities proved to have species richness values close to the highest values reported in previous studies. The patterns typical for stream macroalgal communities (patchy distribution and dominance of few species) were also found in this basin. However, the stream variables most influential in macroalgal distribution in this study (rocky substratum, low pH, high COD, water color, and current velocity) were essentially the same that best describe the limnological characteristics of this lotic ecosystem. In addition, this combination of variables differed sharply from results of previous studies in other Brazilian stream ecosystems. Departamento de Zoologia e Botânica, Instituto de Biociências, Letras e Ciências Exatas (IBILCE), Universidade Estadual Paulista (UNESP), São José do Rio Preto, SP, Brasil Universidade Estadual do Centro-Oeste (UNICENTRO) Universidade Estadual Paulista, Departamento de Zoologia e Botânica, Instituto de Biociências, Letras e Ciências Exatas de São José do Rio Preto FAPESP: 1998/01108-8 CNPq: 520551/96-6 CNPq: 300128/97-5 CNPq: 520257/01-4

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:52:30Z No. of bitstreams: 1 S0100-84042008000100012.pdf: 146752 bytes, checksum: b4176644793ea0826a83cb28a77a42f6 (MD5) Made available in DSpace on 2013-08-22T18:52:30Z (GMT). No. of bitstreams: 1 S0100-84042008000100012.pdf: 146752 bytes, checksum: b4176644793ea0826a83cb28a77a42f6 (MD5) Previous issue date: 2008-03-01 Made available in DSpace on 2013-09-30T19:43:46Z (GMT). No. of bitstreams: 2 S0100-84042008000100012.pdf: 146752 bytes, checksum: b4176644793ea0826a83cb28a77a42f6 (MD5) S0100-84042008000100012.pdf.txt: 45326 bytes, checksum: 6093c4d129316c136dc53deb562ca3ae (MD5) Previous issue date: 2008-03-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T14:03:24Z No. of bitstreams: 2 S0100-84042008000100012.pdf: 146752 bytes, checksum: b4176644793ea0826a83cb28a77a42f6 (MD5) S0100-84042008000100012.pdf.txt: 45326 bytes, checksum: 6093c4d129316c136dc53deb562ca3ae (MD5) Made available in DSpace on 2014-05-20T14:03:24Z (GMT). No. of bitstreams: 2 S0100-84042008000100012.pdf: 146752 bytes, checksum: b4176644793ea0826a83cb28a77a42f6 (MD5) S0100-84042008000100012.pdf.txt: 45326 bytes, checksum: 6093c4d129316c136dc53deb562ca3ae (MD5) Previous issue date: 2008-03-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) O Parque Nacional de Itatiaia (PNI) inclui duas formações vegetais brasileiras em seus limites: floresta pluvial tropical atlântica (MA) e campos de altitude (CA). Foram amostrados 14 pontos, sete em cada formação vegetal, em duas estações do ano (verão e inverno). Foram encontradas 29 espécies de macroalgas, sendo 15 espécies em MA e 19 espécies em CA, com apenas cinco espécies em comum. A riqueza de espécies por ponto de amostragem variou de 1 a 7 (2,9 ± 2,0), o índice de diversidade de Shannon-Wiener (H') de 0 a 0,94 (0,24 ± 0,26) e a cobertura percentual de 0 a 35% (14,0 ± 12,5%). Estes valores situaram-se dentro da amplitude reportada em trabalhos prévios sobre macroalgas lóticas. A análise de regressão múltipla revelou que as variações de temperatura explicaram 39,2% da variação da abundância e 35,5% da riqueza de espécies a ainda que 54,8% da variação da diversidade foi explicada por Demanda Química de Oxigênio (DQO) e pH. Análise de grupamento das comunidades de macroalgas do PNI não agrupou pontos das mesmas regiões (MA e CA). Análise de Componentes Principais separou claramente os pontos amostrados das regiões de MA e CA, bem como das estações do ano estudadas (inverno e verão), influenciados mais fortemente pela temperatura, sombreamento, pH, altitude, potássio e DQO. Os padrões gerais de distribuição em mosaico e dominância por poucas espécies descritos para comunidades de macroalgas lóticas foram corroborados pelos dados do PNI, sugerindo que parecem ser universais para tais comunidades. Itatiaia National Park (INP) includes two kinds of Brazilian vegetation within its limits: Atlantic tropical rainforest (AF) and highland grassland (HG). Fourteen sites were sampled, seven in each region (AF and HG), in two seasons (summer and winter). Twenty nine species of macroalgae were surveyed, from which 15 in AF and 19 in HG, with only five species in common. Species richness per sampling site ranged from 1 to 7 (2.9 ± 2.0), Shannon-Wiener diversity index (H') from 0 to 0.94 (0.24 ± 0.26) and percent cover from 0 to 35% (14.0 ± 12.5%). These values fitted within the range reported in previous studies on lotic macroalgae. Multiple regression analysis revealed that temperature variations accounted for 39.2% of abundance and 35.5% of species richness variations and also that 54.8% of diversity variations were explained by variations of Chemical Oxygen Demand (COD) and pH. Cluster analysis of macroalgal communities of INP did not group sites from the same regions (AF and HG). Principal Component Analysis clearly separated the sampling sites of the two regions, as well as of the two seasons (summer and winter), mostly influenced by temperature, shading, pH, altitude, potassium and COD. The general patterns of patchy distribution and dominance by few species described for lotic macroalgal communities were corroborated by data from INP, suggesting that they seem to be universal for such communities. Universidade Estadual Paulista Departamento de Zoologia e Botânica Universidade Estadual Paulista Departamento de Zoologia e Botânica

O objetivo deste trabalho foi caracterizar a flora arbustivo-arbórea do Parque Estadual do Jaraguá (PEJ), a fim de contribuir para o conhecimento de sua diversidade. Foram feitas coletas mensais de material reprodutivo dos indivíduos arbustivos e arbóreos ao longo de três trilhas, durante um período de 12 meses. O levantamento resultou em uma lista florística contendo 262 espécies nativas, de 153 gêneros e 55 famílias. As famílias mais representativas foram Fabaceae, com 30 espécies, Myrtaceae (26), Asteraceae (24), Melastomataceae (20), Lauraceae (16) e Rubiaceae (15). Assim como relatado para outros remanescentes da região metropolitana de São Paulo e entorno, a vegetação do PEJ está situada em uma zona de transição, onde predomina a floresta ombrófila densa, com a presença de algumas espécies de floresta estacional semidecidual. Destaca-se ainda a existência de uma outra fitofisionomia em uma região de afloramentos de rocha e solo raso, onde ocorrem espécies de cerrado, e que merece estudos específicos. Nessa área, a vegetação é predominantemente herbácea, com árvores e arbustos esparsos, em geral de pequeno porte e com tronco suberoso. Especificamente nessa formação, foram registradas 55 espécies pertencentes a 41 gêneros e 18 famílias, das quais 22 não ocorreram nos outros locais amostrados. A família com maior riqueza foi Asteraceae (15 espécies), seguida por Myrtaceae (7), Fabaceae (5) e Melastomataceae (4). Em todo o levantamento, foram contabilizadas 20 espécies exóticas. Apesar de grande parte da vegetação do Parque ser secundária e estar exposta a fortes pressões antrópicas, foram encontradas 14 espécies presentes em alguma das categorias existentes nas listas oficiais de espécies ameaçadas, reforçando a importância do PEJ para a conservação da biodiversidade. The objective of this study was to characterize the floristic composition of trees and shrubs of the Jaraguá State Park (PEJ), contributing to the knowledge of its biodiversity. Reproductive botanic material was collected along three trails during a 12-month period. The field survey resulted in a flora of 262 native species, 153 genera and 55 families. Fabaceae was the richest family (30 species), followed by Myrtaceae (26), Asteraceae (24), Melastomataceae (20), Lauraceae (16) and Rubiaceae (15). As mentioned for other forest remnants in São Paulo metropolitan region and surroundings, the PEJ vegetation is in a transition zone, where the main formation is the ombrophilous dense forest, but where species of seasonal semi-deciduous forest also occur. Besides that, there is a completely different phytophysiognomy occurring in a region with rocky outcrops and low depth soils, in which cerrado species were found, and that deserves more specific studies. In this site, the vegetation of grasses is the most abundant, and there are also shrubs and trees sparsely distributed, many of them with low height and suberous trunk. Most specifically in this area there were 55 species of 41 genera and 18 families, from which 22 did not occur in the other sites visited. Asteraceae was the family with the higher number of species (15), followed by Myrtaceae (7), Fabaceae (5) and Melastomataceae (4). Twenty exotic species were found along the trails. Despite the fact that PEJ has a big area of secondary vegetation and that it is exposed to strong anthropogenic pressures, there were 14 species belonging to some threat category defined at the official red lists, reinforcing the importance of the Park for biodiversity conservation.