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Hay transfer is a promising method to restore temperate and subtropical grasslands, but its efficiency may depend on the harvesting timing and amount of hay used. We evaluated effects of harvest date (mid‐spring/November, early summer/December, and mid‐summer/February) and hay quantity (500 and 1000 g/m2) on vegetation cover, species richness, and species composition in an experimental study in subtropical southern Brazil for a period of 2 years. We transfer undried hay from a well‐conserved reference area onto a former grassland site degraded by pine plantations. Hay harvested during mid‐spring and early summer led to higher soil cover and species richness compared to the mid‐summer hay treatment in the first year of the experiment. A drought spell decreased vegetation cover in the second year following the hay transfer, with the mid‐spring hay treatment being the least affected. C3 grasses were more effectively introduced by mid‐spring and early summer hay, in contrast to C4 grasses that were better introduced by mid‐summer hay. Lower quantities of hay tended to lead to higher cover and species richness for all harvest dates. Freshly cut undried hay can be an effective way to reintroduce native species in degraded subtropical grasslands. We conclude that timing of hay collection and the amount of hay used influence vegetation cover and species composition at the restoration site and that multiple harvest dates increase restoration success. The drought in the second year of the experiment illustrates the need to consider the possibility of adverse climatic conditions in restoration planning. [ABSTRACT FROM AUTHOR]

Questions: Control of invasive species and seed addition are key steps in grassland restoration. Nevertheless, selecting seed mixes and seed quantities are hard tasks in restoration projects. An interesting idea is to design seed mixes using functional traits and create a community based on limiting similarity to overlap and outcompete the invader. We aimed to test the effect of two sown communities (one created to overlap the invader niche) and three seed sowing densities to reduce the performance of the invasive grass Eragrostis plana. Location: Greenhouse experiment in the Campos Sulinos grasslands region, Southern Brazil. Methods: We created a bifactorial experiment. The first factor was the sown community, each composed of nine native grasses but with different proportions: (1) Limiting, based on limiting similarity, and (2) Balanced, where all species were sown at the same seed weight. We used leaf functional traits (Specific leaf area, leaf area, leaf dry matter content) to design the Limiting community. The second factor was the seed density of native species, sowing twice (1) 1 g/m2, (2) 2 g/m2, and (3) 4 g/m2 (i.e., total density was 2, 4, and 8 g/m2). E. plana was sown once at 0.5 g/m2. Above‐ground and below‐ground biomass of all species were collected after nine months to assess the treatment effects. Results: Biomass production of the invasive species was lower when sown with native species. Nevertheless, both sown communities did not differently affect the invasive biomass production. Higher seed density of native species resulted in lower invasive above‐ground biomass, but not below‐ground biomass. Three native species did not germinate, consequently, the established communities were quite different from those designed. Conclusions: The low species germination limited our discussion about the use of limiting similarity to design seed mixes. High seed sowing density is a better approach when defining sowing strategies to compete with invasive grasses. [ABSTRACT FROM AUTHOR]

Grassy ecosystems occupy 27% of Brazilian territory and have historically been neglected in conservation efforts and studies about biodiversity. The Campos Sulinos region in Southern Brazil includes open formations in the Pampa and Atlantic Forest domains. This region has the smallest coverage by protected areas in the country and presents high levels of biodiversity and endemism. Besides, this region is under threat due to croplands and exotic tree plantations. Here, we compile a plant population genetics and phylogeography dataset from published studies focusing on species native to the Campos Sulinos to synthesize findings in plant evolution and genetics to better understand the dynamics of genetic diversity in this open ecosystem. We found 58 works on 51 plant species, published from 2005 to 2022. Most studies used only one kind of molecular marker and few loci. The climatic changes during the Pleistocene are likely the main speciation driver either due to the dynamics between grassland and forest or marine transgressions. Overall, high genetic variability and clear structuring of populations were found for the species studied. Regions with high genetic diversity do not coincide with protected areas. We reinforce the necessity of considering high intraspecific genetic diversity and population structure into both conservation and restoration planning, as well as in research within the Campos Sulinos.

RESUMO O domínio Pampeano constitui um mosaico vegetacional de campo-floresta, que abriga uma alta riqueza de espécies, incluindo as plantas vasculares dispersas por esporos. O objetivo deste estudo foi inventariar as samambaias e licófitas em um fragmento do Pampa, localizado na Fazenda Estância da Quinta, no município de Rio Pardo, Estado do Rio Grande do Sul. A amostragem ocorreu através do método de caminhamento expedito, realizada em 15 viagens de campo. O material coletado foi identificado através de bibliografia especializada, com posterior incorporação no Herbário da Universidade de Caxias do Sul (HUCS). Atributos ecológicos, geográficos e de conservação das espécies foram registrados em campo e através de busca bibliográfica. O inventário resultou no reconhecimento de 46 espécies de samambaias e uma licófita (Isoetes weberi Herter), pertencentes a 13 famílias. O hábito terrestre (51%) foi predominante, bem como a ocorrência preferencial no interior dos fragmentos florestais (66%). Duas espécies constam em listas de espécies ameaçadas de extinção. Nossos dados reforçam a importância da preservação do mosaico paisagístico do Pampa para manutenção da diversidade deste grupo de plantas do RS.

RESUMO As briófitas estão entre as plantas menos estudadas no Pampa, com apenas cinco estudos brioflorísticos e 124 espécies listadas na Flora e Funga do Brasil. O objetivo desta pesquisa foi compilar informações existentes sobre as briófitas do Pampa como ponto de partida para estudos florísticos, taxonômicos, ecológicos e de conservação, entre outros, além da elaboração de um futuro checklist. Os dados foram extraídos de bancos de dados online, checklists e publicações recentes. Obteve-se uma lista de 318 espécies, o que corresponde a uma diferença de 256% ao número de espécies citadas para o Pampa na Flora e Funga do Brasil. O padrão de distribuição geográfica mundial predominante foi o Neotropical. Oito espécies ocorrem somente no Pampa brasileiro, porém somente Fissidens acacioides var. brevicostatus (Pursell et al.) Pursell é endêmica deste bioma. Constatou-se que sete espécies estão listadas com algum grau de ameaça. Mais estudos são necessários a fim de se conhecer a real riqueza de espécies e incentivar a conservação do bioma.

Disturbances modify local abiotic properties, habitat structure and resource availability, shaping community assembly and ecological interactions. Open ecosystems have an evolutionary relationship with fire. We evaluated the effects of patch burnings on grassland ant communities and patterns of seed removal. We established 14 plots of 10 m2 in pairs in a disturbance-suppressed grassland in South Brazil. A random plot of each pair was burned, and another plot was the control. We accessed ant communities with pitfall-traps and sweeping net, and seed removal with seed traps in all plots prior the experimental fires, and then on three occasions following fires. We recorded 57 ant species belonging to 29 genera. Ant species composition did not significantly vary between treatments neither did ant body size. We detected significantly positive fire effects on ant richness after 1 month and 12 months, mediated by the increase in plant species richness in burned plots. Mean seed removal rates were increased in burned plots after 1 month. We showed that prescribed patch burnings in fire-prone grasslands promoted ant richness, and their foraging activity. Our study may serve as a basis for conservation decisions, showing the importance of maintenance of disturbances in grasslands.

Question: Grazing is an important disturbance for maintenance of structure and functioning of the plant communities in grassy ecosystems. Functional characteristics of plants, which are responsible for their response to grazing, vary at inter‐ and intraspecific levels. Here, we assessed: (1) the extent of intraspecific trait variation when compared to interspecific variability; and (2) how grazing regime affects intraspecific trait variation in leaf functional traits of species with different leaf economics strategies. Location: A multisite grazing experiment in subtropical grasslands, southern Brazil. Methods: For 30 dominant grassland plant species we measured functional traits related to resource acquisition strategy and grazing response (SLA, specific leaf area; LDMC, leaf dry matter content; LA, leaf area; and FT, leaf resistance to traction) under three grazing treatments (grazing exclusion, traditional, or deferred grazing) arranged in a randomized block design. We quantified the overall proportion of intra‐ and interspecific variation and, for each species, we tested for the grazing treatment effects on intraspecific trait variation through Bayesian analysis of variance. Results: The overall contribution of intraspecific variation was up to 37% of the total variation. For most grass species, grazing exclusion led to lower values of SLA and higher values of LA, while no effect of grazing treatments was detected on intraspecific variation of LDMC and FT. Altogether, the effect of grazing management on intraspecific trait variation was more prevalent in species presenting a conservative strategy than in species with an acquisitive strategy. Conclusion: The expression of leaf traits is variable within species, especially for those species with a conservative strategy of resource acquisition. The extent of intraspecific trait variation in response to grazing depends on the considered traits and the resource acquisition strategy of the studied species. [ABSTRACT FROM AUTHOR]

We describe two new species of Calibrachoa (Solanaceae) from southern Brazil grasslands. The new species were first detected by molecular data, and later corroborated by morphological traits and field observations. Both species are erect shrubs with showy purple corollas. The main distinctive morphological traits are the marked dark purple ring contrasting with the yellow corolla throat and the lobed stigma in C. atropurpurea, and the long androecium reaching the distal part of the corolla tube and the connivent anthers in C. synanthera. A key for the species with purple flowers from the Rio Grande do Sul Brazilian State, where the species were found, is given. [ABSTRACT FROM AUTHOR]

• Brazilian environmental legislation can assist in the conservation of grassland ecosystems. • The presence of cattle in Permanent Preservation Areas of a rural matrix increases the diversity of species. • The presence of cattle in Permanent Preservation Areas increases the litter cycling, reducing dry cover and, consequently, the incidence of fires. • In this study, the Preservation Areas fulfill their objective of preserving grassland species. • The permanence of cattle in protected areas provides the preservation of the diversity and physiognomy of grasslands. The Pampa biome comprises a high species richness, but has been transformed by various human activities, threatening its inherent diversity. One of the mechanisms that contributes to conservation is the Permanent Preservation Areas (PPA); however, studies related to the vegetation of these areas are scarce, especially regarding the herbaceous stratum, creating a gap in the evaluation of the conservation of the Pampa biome's grassland formations. The objective of this study was to characterize the structure of fragments of grasslands in PPA, with and without cattle grazing, inserted in a plantation of Eucalyptus saligna Sm. in the Pampa biome. The survey was conducted on 40 systematically distributed sample units in six grassland areas, three of which were occasionally exposed to grazing and three fenced off with no grazing. Cover and frequency values ​​(absolute and relative) and importance value index (IVI) were estimated for species, exposed soil and dry plant material. The difference between the areas was evaluated by the Principal Coordinate Analysis (PCoA) and ANOSIM, complemented by SIMPER. Richness, dry plant material and exposed soil were evaluated using the Kruskall-Wallis test. A total of 210 species were registered, with the Poaceae family being the most numerous, followed by Asteraceae (41), Cyperaceae (19), Fabaceae (12) and Rubiaceae (9). The areas differed in relation to richness, with grazing showing more diversity. Enclosure Area 3 did not differ from open areas 2 and 3, possibly due to the greater proximity and low cattle interference. The exposed soil did not vary according to the enclosure; however, the dry plant material was higher in the enclosed areas. The distribution of species, as well as their cover and frequency were regulated according to grazing. The presence of animals in PPA has modified the dynamics and botanical composition of the areas, in which richness was promoted. [ABSTRACT FROM AUTHOR]

The Pampa biome within Brazil is one of South America's most endangered biomes, due to conversion to croplands and use for cattle farming, with very limited coverage by protected areas. We investigated the impacts of (i) human population density, (ii) grassland and (iii) forest cover, (iv) protected areas and (v) mean size of farms on the occurrence patterns of 18 medium‐sized mammal species. We gathered information on the occurrence of these species between 2001 and 2010 from the literature and using unpublished field data from local experts. We obtained 1066 records, varying between 13 and 101 per species. Grassland cover had consistently positive effects on species richness (considering the 18 analyzed species), endangered species (considering 10 species that are endangered or data deficient) and occurrence of five individual species (considering each species separately). Human population density, forest cover and mean size of farms had diverse effects on individual species; however, both forest cover and human population density had positive effects on species richness and endangered species occurrence. For human population density this may result from areas suitable for people being similar to those suitable for many native species. The protected area network of the Pampa biome appeared ineffective at protecting the focal species, with predominantly negative effects on mammal occurrence. This inefficiency is probably related to its minor coverage; only 2.9% of the biome area is under any level of protection and only 0.4% under strict protection. To guarantee the conservation of mammal species in this threatened biome, it is important to protect the last remnants of native vegetation, mainly grasslands, avoiding their conversion into croplands. [ABSTRACT FROM AUTHOR]

Fire has long been recognized as an important driver of vegetation patterns, and is of particular importance for biodiversity maintenance in many grassland systems, including the North American tallgrass prairie. Here, it has been successfully used as a conservation and restoration tool. In southern Brazil, grasslands appear to present many similarities to tallgrass prairie in terms of composition and ecology, but the role of fire has been poorly studied and it is not usually used in conservation. Here, we compare plant genera and family composition of tallgrass prairie and South Brazilian grassland sites. We find striking similarities in terms of dominant families, genera, and functional types. The similarities between plant communities suggest similarities in ecological processes and should lead to a re-thinking of conservation strategies in South Brazilian grasslands. Research on the role of fire is needed, and comparative North–South studies on grasslands in the Americas likely will provide important insights for grassland ecology and management.

Endemic, small range species are susceptible to environmental changes and landscape modification. Understanding genetic diversity and distributional patterns is important for implementation of effective conservation measures. In this context, genetic diversity was evaluated to update the conservation status of an endemic tuco-tuco, Ctenomys ibicuiensis. Phylogeographic and population genetic analyses of mitochondrial DNA and microsatellite loci were carried out using 46 individuals sampled across the species' distribution. Ctenomys ibicuiensis presented moderate to high genetic diversity and highly structured populations with low levels of gene flow and isolation by distance. Anthropogenic landscape changes threaten this restricted-range tuco-tuco. Considering its limited geographic distribution and highly structured populations with low gene flow, we consider C. ibicuiensis to be at significant risk of extinction. [ABSTRACT FROM AUTHOR]

Aims South American Pampa grasslands are habitats of great conservation interest, with a distinct and rich flora, but have been intensely converted to other land uses, including tree plantations. While necessity for restoration grows, no information on restoration potential of grasslands after afforestation exists. Here, we aim at analyzing composition and structure of grassland vegetation with a history of eucalyptus plantations in order to assess recovery potential of these areas. We hypothesized that areas with history of eucalyptus would differ from reference grasslands with no history of land-use change in terms of floristic and functional composition and would present lower species richness. Methods Our study region comprised four sites in the southeastern part of the Pampa biome, in the coastal plain in the extreme south of Brazil, always with sites with long (50 years) history of eucalyptus plantation and reference grassland. We sampled vegetation at post-eucalyptus sites (with and without resprouting) 10 years after clearclutting and in natural grasslands. We analyzed data by analysis of variance and ordination techniques, considering compositional parameters and life forms, and indicator species analysis. Important Findings Species richness and vegetation cover were higher in reference grassland than in resprout areas but did not differ from post-eucalyptus areas. Exotic species cover was significantly higher in areas with afforestation history. In terms of total composition, natural grasslands differed significantly from areas with past plantation use. Indicator species analyses revealed considerable differences between grassland types. In conclusion, vegetation development led to grassland communities that are still quite distinct from reference sites. Likely, the specificity of grassland management has a high importance in defining vegetation trajectories in time and importance for grassland recovery, and restoration needs to be addressed in more studies. [ABSTRACT FROM AUTHOR]

Pseudolucia parana Bálint, 1993 was described from Castro, Paraná, Brazil, where it was first collected over 120 years ago. It was observed/collected quite sporadically in the second half of the 20th century in a few isolated habitats in the State of Paraná. Excluding a single record since the early 2000s, the species was not observed in all its known sites in Paraná due to urbanization of its habitats or change of land use. Consequently the species in Paraná state is highly endangered, possibly extinct. Efforts to find the species in the state Santa Catarina failed. A new hope to the survival of the species appeared in the southernmost state Rio Grande do Sul, where some relict populations are documented. The results of rescue expeditions to several granitic hills in the region are presented and the current distribution P. parana is assessed. First descriptions of its early stages, ecology, ethology and recommendations for conservation are given. The data provided indicate that the global status of P. parana should be Critically Endangered. Some molecular traits of P. parana are analysed resulting in a preliminary assessment for the age of the populations. With 24 figures. [ABSTRACT FROM AUTHOR]

• Hay has the potential to introduce graminoid seeds in South Brazilian grasslands. • More than one hay collection should be prioritized. • Forbs did not emerge from hay and other introduction forms should be considered. • Grassland management can influence the best hay amount to be used. Subtropical grasslands have been severely impacted. Due to their low resilience after degradation, active restoration is necessary; however, knowledge still is incipient. Hay transfer is a successfully employed technique to restore other grassland ecosystems and its use is promising in subtropical grasslands. We evaluated the potential of hay transfer for the restoration of the subtropical grasslands in Southern Brazil by assessing the effects of (1) the date of hay harvest and (2) the amount of dry hay used. In two protected areas in South Brazilian grasslands, we harvested hay on three dates (mid-Spring, early-Summer, and mid-Summer) and placed it into a greenhouse for seeds in the hay to germinate. Two different amounts of dry hay (375 g/m² and 750 g/m²) were used for each date. We assessed the number of emerging seedlings, species richness, and seedling species composition in each treatment, separately for each site. Emerging forbs were identified as soil seed bank contamination, and only data for graminoids (grasses and sedges) are presented. The number of seedlings varied among harvest dates, with mid-Spring and early-Summer resulting in more emergencies in both sites. No common pattern to both sites regarding the effect of the amount of dry hay on seedling emergence was found for the two sites, but interaction with the harvest date is important. Species composition and richness also varied across harvest dates, and, independent of the donor site, more hay resulted in more species. Nevertheless, few species were transferred overall. Hay transfer has the potential to introduce seeds of graminoids and appears to be a promising tool for the restoration of South Brazilian grasslands. There is not a single optimal time for hay harvest nor a pattern regarding hay amount. Few species are established from hay and more than one harvest should be done to increase species richness. [ABSTRACT FROM AUTHOR]

Abstract Between July 2014 and April 2015, we conducted weekly inventories of the circadian activity patterns of mammals in Passo Novo locality, municipality of Alegrete, southern Brazil. The vegetation is comprised by a grassy-woody steppe (grassland). We used two camera traps alternately located on one of four 1 km transects, each separated by 1 km. We classified the activity pattern of species by the percentage of photographic records taken in each daily period. We identify Cuniculus paca individuals by differences in the patterns of flank spots. We then estimate the density 1) considering the area of riparian forest present in the sampling area, and 2) through capture/recapture analysis. Cuniculus paca, Conepatus chinga and Hydrochoerus hydrochaeris were nocturnal, Cerdocyon thous had a crepuscular/nocturnal pattern, while Mazama gouazoubira was cathemeral. The patterns of circadian activity observed for medium and large mammals in this Pampa region (southern grasslands) may reflect not only evolutionary, biological and ecological affects, but also human impacts not assessed in this study. We identified ten individuals of C. paca through skin spot patterns during the study period, which were recorded in different transects and months. The minimum population density of C. paca was 3.5 individuals per km2 (resident animals only) and the total density estimates varied from 7.1 to 11.8 individuals per km2, when considering all individuals recorded or the result of the capture/recapture analysis, respectively.

The expansion of land use for agriculture is among the main reasons for the reduction of natural grasslands around the world, and little is known about the recovery potential of original native grassland vegetation from seed banks. The aim of this study was to assess the seed bank potential of grassland areas with or without history of cultivation in southern Brazil. Specifically, we aimed at evaluating if agricultural use allowed for the persistence of species typical of natural grasslands in soil seed banks. We analyzed seed banks in two areas with a history of cultivation and in two natural grasslands. Samples were collected in spring and autumn in order to assess transient and persistent components, and were characterized by density, richness, presence of exotic species and relationship between seed bank and established vegetation. Both richness and density were high; we found a total of 114 species and a mean density of 61,796 seedlings/m2 for all four areas in the spring sampling. In the natural grasslands, the dominant species of established vegetation were mostly absent from the soil seed bank. Our study indicates that the seed bank is of little relevance for the recovery of typical grassland vegetation after disturbance.

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We present the taxonomic treatment of the Xyridaceae family for the state of Paraná. It is represented exclusively by the genus Xyris, with 22 species typical of grasslands. Three new records are reported for the state: Xyris glandacea, X. metallica and X. uninervis, all of them extends its distribution area to southern Brazil. Other novelties are a new synonym (Xyris simulans var. subtortula under Xyris asperula) and the reestablishment of Xyris dusenii. An identification key, descriptions, comments, illustrations and data on the geographical distribution of the species are provided. [ABSTRACT FROM AUTHOR]

Background: In Southern Brazil, large areas of grassland have been replaced by Eucalyptus plantations. Vegetation is scarce under plantations which may be associated with Eucalyptus releasing of allelochemicals. Aims: To investigate effects of Eucalyptus saligna leaf litter on the colonisation and development of the ground layer by grassland species and if these effects were related to allelopathy. Methods: We assessed the effects of Eucalyptus litter on the establishment of species of the native grassland community and on seeded test species (Paspalum notatum and Lotus corniculatus - introduced). We tested the impact of the addition of E. saligna leaf litter, artificial leaves (shading and mechanical impediment) and shading. We also tested the phytotoxicity of the soil from E. saligna plantations. Results: Species richness, diversity, plant height, cover and biomass were lower in E. saligna leaves and artificial leaves treatments than in the control (absence of litter). The test species showed lower biomass and higher mortality in treatment plots with E. saligna leaves, artificial leaves and shading treatments than in the control. Allelochemicals did not accumulate in soil at phytotoxic levels. Conclusions: Eucalyptus saligna leaf litter suppresses the establishment of grassland vegetation, but the effects are mainly physical. Field evaluations with appropriate controls should be more extensively used  in allelopathy investigations. [ABSTRACT FROM AUTHOR]

Non-forest ecosystems, as natural grasslands from Southern Brazil, are still neglected in conservation policies. Measuring their biodiversity is one of the main steps to generate management strategies for these habitats. This study aims to (i) describe grassland ant richness and composition in Rio Grande do Sul state, and (ii) compare ant communities sampled on the ground and in grassland vegetation, adding to our knowledge of habitat use patterns and vegetation associated species. Six sites were sampled, three belonging to the Pampa biome and three in highland region from the Atlantic Forest biome. Ant fauna was collected once per year in summer during four years in each site with pitfalls traps and sweeping nets. Overall, 29,812 ant individuals were sampled belonging to eight subfamilies, 30 genera e 106 species. The grasslands of Pampa accumulated 91 species and 45 exclusive species, while highland grasslands summed up 61 species and only 15 exclusive species. Species composition differs between biomes as well as between sampling methods. Ant communities sampled from vegetation represented a clear subset of the fauna sampled with pitfall traps, and indication analysis showed only two species associated with this stratum: Myrmelachista gallicola and Pseudomyrmex nr. flavidulus. This study highlights the importance of Southern Brazilian grasslands and the need for specific conservation strategies for the natural grasslands from each biome.

ABSTRACT A new species of Ituglanis associated to the grasslands of the Pampa biome is described from the rio Uruguai basin, southern Brazil. The new species is distinguished from its congeners by the low number of ribs and by a unique color pattern composed of an outer layer with scattered round black blotches equivalent in size to the eye circumference over a reddish brown background on the lateral surface of the body. We provide the genetic sequences of the mitochondrial gene Cytochrome c Oxydase subunit I (COI) for three of the paratypes and discuss aspects about the recent discovery of the new species.

Considerado um bioma ameaçado, o Pampa possui um dos menores percentuais de área legalmente protegida. Além disso, o conhecimento sobre comunidades de anuros neste bioma ainda é escasso. Nesse contexto, o objetivo deste estudo foi determinar a composição de anuros em uma área de Pampa no sul do Brasil. Entre janeiro de 2009 e fevereiro de 2010 foi realizado um inventário na Fundação Estadual de Pesquisa Agropecuária do município de São Gabriel, Rio Grande do Sul. A procura dos exemplares foi realizada em poças permanentes, semi-permanentes e temporárias pelo método de levantamento em sítio de reprodução. Foram registradas 21 espécies pertencentes a cinco famílias, o que corresponde a aproximadamente 20% das espécies do estado e 42% das espécies conhecidas para a ecorregião Savana Uruguaia. Dez espécies foram consideradas frequentes, sete comuns e quatro foram raras. Foram registrados três modos reprodutivos, sendo que 57% das espécies utilizam o modo 1, que parece estar relacionado à homogeneidade da área. A análise de agrupamento comparando a composição de anuros de quatro localidades distintas mostrou maior similaridade com o município de Candiota (região da Campanha). As espécies presentes na área de estudo são associadas a formações campestres do estado e países vizinhos e podem ser consideradas típicas do bioma Pampa.

Land-use changes such as conversion of semi-natural grasslands to agriculture, silviculture, or highintensity pastures affect biodiversity and ecosystem functions and services. However, which ecosystem functions are affected when highly diverse grasslands are converted remains largely unknown. As a model system, we studied 80 grasslands in Rio Grande do Sul, southern Brazil, comprising exceptionally diverse permanent grasslands that are traditionally managed with burning of accumulated biomass and moderate grazing, and four additional grassland types with different present or historical management: permanent grasslands with reduced or increased current management intensity and secondary grasslands after past agricultural or silvicultural use. We measured ten ecosystem functions covering all major below- and aboveground ecosystem components and the processes that link them, using the novel rapid ecosystem function assessment approach. Ecosystem functions included primary and secondary production, and species interactions, that is, herbivory, pollination, predation, seed dispersal, and decomposition. Ecosystem functions differed significantly among grassland types, most distinctly between permanent and secondary grasslands. Historical land-use changes to agriculture and silviculture led to altered ecosystem functions even after reconversion to grassland, including lower primary and secondary production, lower decomposition, lower seed dispersal capabilities, and higher invertebrate herbivory. Current management practices explained additional variation in some ecosystem functions, including strong positive effects of intensified management on secondary production. Other ecosystem functions such as pollination and predation were not affected. The findings suggest that conversion of grasslands to more intensive land-use types has long-lasting consequences for some ecosystem functions, with effects persisting even many years after reconversion, resulting in changes in the ecosystem services provided by these grasslands. [ABSTRACT FROM AUTHOR]

A new species of Ituglanis associated to the grasslands of the Pampa biome is described from the rio Uruguai basin, southern Brazil. The new species is distinguished from its congeners by the low number of ribs and by a unique color pattern composed of an outer layer with scattered round black blotches equivalent in size to the eye circumference over a reddish brown background on the lateral surface of the body. We provide the genetic sequences of the mitochondrial gene Cytochrome c Oxydase subunit I (COI) for three of the paratypes and discuss aspects about the recent discovery of the new species. [ABSTRACT FROM AUTHOR]

Copyright of SHILAP Revista de Lepidopterologia is the property of Sociedad Hispano-Luso-Americana de Lepidopterologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract The International Union for Conservation of Nature listed gorse (Ulex europaeus, Fabaceae), a heliophilous evergreen shrub, as one of the world's 100 worst invasive species. Over the years, multiple attempts have been made for controlling gorse, including biological methods, but they have not been fully successful. This study aims to investigate some aspects that still remain unexplored such as the relationship between anthropogenic disturbances with the spatial mechanisms of species spread. We aimed to fill this gap by analyzing the role of transportation network configurations and landscape context on gorse propagation. We surveyed the presence of gorse in southern Brazilian forest‐grassland mosaics by completing landscape‐level road transects coupled with remote sensing, to evaluate land use and landscape structure. A binary logistic regression model was performed to test the influence of independent variables (e.g., road orientation, type and category in addition to distance to the nearest habitat patch of forest, grassland and anthropogenic area) on gorse occurrence. Our results showed that the structure of road networks can facilitate the spread of heliophilous taxa like gorse. Specifically, local, paved, NWSE and NS‐oriented (which exhibited high light exposure) roads had the highest probability of finding gorse. This suggests that human transportation activity (traffic, road construction, and maintenance) constitutes a significant dispersal agent for the species. In addition, the landscape matrix context also played a significant role; gorse was most prevalent along roadsides close to urban or agricultural areas than to forests and grasslands. No area was completely free from disturbances, such as fire, livestock grazing, and silviculture, in these seminatural landscapes. We concluded that, disturbances affecting small‐scale processes, at roadside and adjacent habitat patches, were probably as important factors explaining gorse occurrence as the urban impact. Furthermore, the current work also emphasizes the need of understanding the complexity of interacting factors. Our work has important implications for ecosystem conservation and habitat management, and consequently should be considered a prior step in establishing new approaches for gorse control.

The increasing human occupation of natural environments is one of the greatest threats to biodiversity. To mitigate the negative anthropogenic effects, it is necessary to understand the characteristics of natural populations and the natural history of species. A study was conducted with an assemblage of lizards from a disturbed area of the Pampa biome, from February 2001 to January 2004. The assemblage showed a unimodal seasonal pattern, with the recruitment period occurring during the warmer months. The captures were seasonal for two of the three monitored years, and concentrated within warmer months. The minimum temperature explained the number of catches for the assemblage as a whole. However, when the species were analyzed individually, the temperature only explained the seasonal occurrence of Teius oculatus. The abundance of species was significantly different in the third year of study for Cercosaura schreibersii and Ophiodes striatus. This latter species was no longer registered in the study area from May 2003 until the end of the study. Therefore, O. striatus may be more sensitive to environmental changes, considering the events of change in vegetation during the study. With frequent and increasing environmental disturbances, it is necessary to take conservation measures and encourage the increase of knowledge on Pampean lizards.O crescimento da ocupação humana sobre ambientes naturais é uma das maiores ameaças à biodiversidade. Para amenizar os efeitos negativos antropogênicos, é necessário entender as características das populações naturais, e a história natural das espécies. Um estudo foi conduzido com uma assembeia de lagartos de uma área perturbada do Pampa, de fevereiro de 2002 a janeiro de 2004. A assembleia apresentou padrão sazonal unimodal, com recrutamento ocorrendo durante os meses mais quentes. As capturas foram sazonais durante dois dos três anos monitorados, e concentradas nos meses mais quentes. A temperatura mínima explica o número de capturas para a assembleia como um todo. Entretanto, quando as espécies foram analisadas individualmente, a variável explica apenas a ocorrência sazonal de Teius oculatus. A abundância das espécies foi significativamente distinta no terceiro ano de estudo para Cercosaura schreibersii e Ophiodes striatus. Essa última espécie não teve mais registros na área de maio de 2003 até o final do estudo. Assim, O. striatus pode ser mais sensível às udanças abientais, considerando os eventos de udança na vegetação ocorridas durante o estudo. Com as frequentes e crescentes perturbações ambientais que o bioma vem sofrendo, são necessárias ações de conservação, e dar suporte para o aumento do conhecimento dos lagartos pampeanos.

O objetivo deste trabalho foi avaliar as produções vegetal e animal e a resposta econômica de uma pastagem natural submetida à adubação de correção e doses de nitrogênio durante a estação de crescimento 1998/99. O experimento foi conduzido em área da Estação Experimental Agronômica da Universidade Federal do Rio Grande do Sul (EEA - UFRGS). Em 1996 foram aplicados 3000kg ha-1 de calcário e adubação correspondente a 500kg ha-1 da fórmula 5-20-20. Na análise econômica, considerou-se um terço destas quantidades como referente à utilização na estação de crescimento 1998/99. Os tratamentos foram doses de nitrogênio (N) na forma de uréia (zero, 100 e 200kg ha-1 de N), em um delineamento de blocos ao acaso com duas repetições de área por tratamento. Os animais experimentais foram novilhas de corte com um ano de idade e peso médio inicial de 160kg. A massa de forragem, a taxa de acúmulo diário de matéria seca, a produção total de matéria seca verde e a eficiência de transformação do N em produção primária foram maiores (PThis research was aimed at evaluating the plant and animal production and the economic response of a native pasture submitted to the application of N-P-K and nitrogen levels during the 1998/99 growing season. The experiment was conducted at Estação Experimental Agronômica of the Universidade Federal do Rio Grande do Sul (EEA - UFRGS). The pasture was fertilized in 1996 using 3000kg ha-1 of lime and 500kg ha-1 of 5-20-20. The one third of these amounts was considered as that concerning the 1998/99 growing season, in the economic analysis. The treatments were nitrogen (N) levels (zero, 100 and 200kg ha-1 of N) as urea, in a randomized block design with two plots by treatment. The experimental animals were beef heifers with initial age of 1,5 year-old and average live weight of 160kg. The forage mass, dry matter accumulation rate, green dry matter total production and the N transformation efficiency in primary production were enhanced by the N level applied (P< 0.1). The treatments 100 and 200kg ha-1 of N increased the costs in 104.1 and 208.2%, respectively. The treatment 200kg ha-1 of N presented the greater area live weight gain, the gross margin and the N conversion efficiency in animal product. The greater net financial return was reached when only lime and N-P-K fertilization were applied. The native pasture showed a positive response to the fertilizer application, within the amplitude of amount of the input applied in this experiment.

The International Union for Conservation of Nature listed gorse (Ulex europaeus, Fabaceae), a heliophilous evergreen shrub, as one of the world's 100 worst invasive species. Over the years, multiple attempts have been made for controlling gorse, including biological methods, but they have not been fully successful. This study aims to investigate some aspects that still remain unexplored such as the relationship between anthropogenic disturbances with the spatial mechanisms of species spread. We aimed to fill this gap by analyzing the role of transportation network configurations and landscape context on gorse propagation. We surveyed the presence of gorse in southern Brazilian forest‐grassland mosaics by completing landscape‐level road transects coupled with remote sensing, to evaluate land use and landscape structure. A binary logistic regression model was performed to test the influence of independent variables (e.g., road orientation, type and category in addition to distance to the nearest habitat patch of forest, grassland and anthropogenic area) on gorse occurrence. Our results showed that the structure of road networks can facilitate the spread of heliophilous taxa like gorse. Specifically, local, paved, NWSE and NS‐oriented (which exhibited high light exposure) roads had the highest probability of finding gorse. This suggests that human transportation activity (traffic, road construction, and maintenance) constitutes a significant dispersal agent for the species. In addition, the landscape matrix context also played a significant role; gorse was most prevalent along roadsides close to urban or agricultural areas than to forests and grasslands. No area was completely free from disturbances, such as fire, livestock grazing, and silviculture, in these seminatural landscapes. We concluded that, disturbances affecting small‐scale processes, at roadside and adjacent habitat patches, were probably as important factors explaining gorse occurrence as the urban impact. Furthermore, the current work also emphasizes the need of understanding the complexity of interacting factors. Our work has important implications for ecosystem conservation and habitat management, and consequently should be considered a prior step in establishing new approaches for gorse control. [ABSTRACT FROM AUTHOR]

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This is a biogeographical study in a regional scale performed in order to detect patterns of grassland plant distribution in the Campos Gerais of Paraná, in south Brazil. It was employed a presence/absence matrix with 471 species from phytosociological data and 1,455 species from floristic surveys of seven phytocoenosis. It was calculated the Biogeographycal Similarity Coefficient as well Harrison and Wilson & Schmida beta diversity index. So, we work with the hypothesis of a vicariance scenario, namely the fragmentation of a former wider distribution of grassland, occupied by savannah that scatters from the core of the Biome, following climatic fluctuations. [ABSTRACT FROM AUTHOR]

Copyright of Ambiência is the property of Revista Ambiencia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Phytotoxicity has often been proposed as evidence of allelopathy. However, few studies have investigated allelopathy in natural field conditions. In South Brazilian grasslands, Heterothalamus psiadioides, a shrub establishing in dense stands, has shown strong phytotoxicity in laboratory assays. We conducted a field study to evaluate if this species also negatively affects a plant community through allelopathy. At a shrubland site, we established a phytotoxicity gradient, consisting of plots with H. psiadioides, plots with Baccharis patens-a shrub with minimal phytotoxicity-and plots without shrubs (no phytotoxicity). We assessed plant species cover, biomass, number of seedlings, diversity, richness, and plant community characteristics. Our study did not show evidences of plant inhibition near the phytotoxic species. We observed higher plant richness and diversity in plots with H. psiadioides than in plots with B. patens and without shrubs. The highest diversity near H. psiadioides was associated with greater forb cover, due to lower cover of dominant grasses. Differences in light incidence accounted for vegetation patterns more than allelopathic activity. Therefore, our study showed that the allelopathic potential of the evaluated species was overestimated based only on laboratory studies. We emphasize the relevance of conducting allelopathy studies in field and of having a similar species with low phytotoxicity in this kind of study. Results based only on laboratory assays and visual evidence of patterns in field may be misleading and may lead to an overestimation of the role of allelopathy in plant communities. [ABSTRACT FROM AUTHOR]

O presente estudo teve como enfoque o grupo de plantas Eudicotiledôneas nativas dos campos do bioma Pampa localizado no sul do Brasil com potencial ornamental. O Pampa apresenta elevada biodiversidade, entretanto necessita de estudos quanto à riqueza de plantas vasculares e seu conhecimento biológico e ecológico. O objetivo desse trabalho foi elaborar um inventário preliminar desse grupo de vegetais, avaliando o potencial ornamental de cada espécie, indicando aquelas que poderiam ser consideradas prioritárias para uso sustentável com essa finalidade. Foram selecionadas algumas espécies campestres por meio da busca de informações em registros de herbário, obras nacionais e internacionais sobre plantas ornamentais, levantamentos florísticos, além do conhecimento prático dos autores. Foram estabelecidos alguns parâmetros e valores a eles associados, visando a reduzir a subjetividade da escolha. O levantamento resultou em uma lista de 177 espécies, distribuídas entre 36 famílias e 101 gêneros. Das 177 espécies, dez apresentaram elevado potencial ornamental. Esses dados indicam que a riqueza da flora nativa ornamental dos campos da região é elevada, ainda que pouco conhecido o seu aproveitamento. A utilização dessas plantas, desde que de forma sustentável, poderá gerar benefícios econômicos e ecológicos.

Copyright of Biota Neotropica is the property of Biota Neotropica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Biota Neotropica is the property of Biota Neotropica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)