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.

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.

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.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In this study, we sampled two anuran communities in two physiographic regions of the Pampa biome, Serra do Sudeste and Depressão Central, were made monthly campaigns during the period between September 2011 and August 2012 where there were registered 25 species of frogs. Scinax granulatus, Physalaemus gracilis e Pseudis minuta were the most abundant species in the Serra do Sudeste, while Dendropsophus minutus, D. sanborni and Scinax squalirostris were the most abundant of the Depressão Central. We recorded 15 species of frogs in the larval stage and four reproductive modes classified as generalists. Ordination analysis showed a segregation among the two physiographic regions, related to anurofauna with a difference of 65% between them. The influence of environmental descriptors and physicochemical variables of water in the structure of the two communities showed that the set of variables, pH, number of extracts of emergent vegetation and temperature were important in structuring the community of Depressão Central, as dissolved oxygen, electrical conductivity number of extracts of emergent vegetation, hydroperiod and percentage of vegetation cover were important factors structuring the community of Serra do Sudeste. However the abundance and richness of the Serra do Sudeste community showed no significant relation with the variables tested and the distance between the puddles did not influence the structure of both communities. / Neste estudo, foram amostradas duas comunidades de anuros em duas regiões fisiográficas do bioma Pampa, a Serra do Sudeste e a Depressão Central, nestas, foram realizadas campanhas mensais durante o período de setembro de 2011 a agosto de 2012 onde foram registradas 25 espécies de anuros. Scinax granulatus, Physalaemus gracilis e Pseudis minuta foram as espécies mais abundantes na Serra do Sudeste, enquanto Dendropsophus minutus, D. sanborni e Scinax squalirostris foram as mais abundantes da Depressão Central. Foram registrados 15 espécies de anuros em estágio larval e quatro modos reprodutivos generalistas. A análise de ordenação mostrou uma segregação quanto a anurofauna das duas regiões fisiográficas e uma diferença de 65% entre elas. A influência dos descritores ambientais e das variáveis físico-químicas da água na estrutura das duas comunidades mostrou que o conjunto de variáveis, pH, número de extratos de vegetação emergente e temperatura foram importantes na estruturação da comunidade da Depressão Central, já o oxigênio dissolvido, condutividade elétrica número de extratos de vegetação emergente, hidroperíodo e porcentagem de cobertura vegetal foram importantes estruturadores da comunidade da Serra do Sudeste. A abundância e a riqueza de anuros da Serra do Sudeste não apresentou relação significativa com as variáveis testadas e a distância entre as poças não influenciou na estrutura das mesmas.

O presente trabalho foi desenvolvido na Estação Experimental do INIA La Estanzuela, em Colonia del Sacramento – Uruguai, de novembro de 2015 a março de 2017, com o objetivo de avaliar os parâmetros relacionados à produção e qualidade de sementes da espécie Paspalum notatum INIA Sepé. Buscou-se o entendimento dos componentes do rendimento de sementes frente a distintos níveis de fertilização nitrogenada e manejo de cortes. Foi utilizado o delineamento de blocos completamente casualizados com quatro repetições. Os tratamentos consistiram de quatro doses de fertilização nitrogenada (0, 75, 150 e 225 kg de N.ha-1) e três momentos de corte: corte precoce, corte tardio e sem corte, formando um arranjo fatorial 4x3. O padrão para realização do corte foi a fração da radiação fotossinteticamente ativa interceptada pelas plantas (50% para corte precoce e 80% para corte tardio). Para cada ano de estudo foram utilizados distintos locais dentro da mesma estação experimental a fim de avaliar a produção de sementes de plantas com idade similar (3 anos de idade), os quais foram denominados ambiente 2016 e ambiente 2017, sendo que no ambiente 2016 ocorreu maior deficiência hídrica no solo A aplicação de N possibilitou o incremento na massa de forragem, teor de proteína bruta, índice de nutrição nitrogenada e no número de perfilhos. A máxima produtividade de sementes alcançada situou-se próxima de 1000 kg.ha-1, rendimento atingido com 150 kg de N.ha-1 no ambiente 2016 e na dose 75 no ambiente 2017. Tal produtividade foi obtida com a realização de duas colheitas anuais, que foi possibilitada com a utilização de corte precoce e sem corte. Com o uso de corte tardio, por outro lado, foi possível a realização de apenas uma colheita anual, o que determinou menor rendimento total de sementes, porém possibilitou maior rendimento em apenas uma colheita. Com relação ao potencial germinativo das sementes, observamos que em situações de déficit hídrico, as plantas com suprimento de N comprometem a qualidade de sementes e favorecem o crescimento vegetativo, no caso de colheitas precoces. Por outro lado, a germinação foi melhorada quando aplicado nitrogênio associado ao corte tardio. Dessa forma, conclui-se que o ecótipo Paspalum notatum INIA Sepé possui bom rendimento de sementes, o qual é positivamente influenciado pela fertilização nitrogenada e aplicação de corte precoce. / The present work was developed at the INIA La Estanzuela Experimental Station, in Colonia del Sacramento, Uruguay, from November 2015 to March 2017, with the objective of evaluating the parameters related to the production and quality of seeds of the specie Paspalum notatum INIA Sepé. We aimed understanding of the components of the seed yield under different levels of nitrogen fertilization and cutting management. A completely randomized block design with four replications was used. The treatments consisted of twelve factorial combinations of nitrogen fertilization doses (0, 75, 150 and 225 kg of N.ha-1) and three cutting times: early cut, late cut and no cut, totaling a factorial arrangement 4x3. The standard for cutting was the fraction of the photosynthetically active radiation intercepted by the plants (50% for early cutting and 80% for late cutting). For each year of study, different locations were used within the same experimental station in order to evaluate the seed production of plants with similar age (3 years old), which were named environment 2016 and environment 2017, wherein in the environment 2016 occurred greater soil water deficit The application of N promoted the increase in forage mass, crude protein content, nitrogen nutrition index and the number of tillers. The maximum seed yield reached was close to 1000 kg.ha-1, yield reached with 150 kg of N.ha-1 in the environment 2016 and at dose 75 in the environment 2017. Such productivity was obtained by performing two harvests annually, which was possible by the use of early cutting and uncut treatments. However, with late cutting was possible to perform only one annual harvest, which resulted in lower total seed yield, but with a higher yield in only one harvest. Regarding to the seed germination, we observed that in situations of water deficit, plants with N supply compromise their seed quality in detriment of vegetative growth in the case of early harvests. On the other hand, the germination was improved when N was associated with late cut. In this way, we concluded that Paspalum notatum INIA Sepé ecotype has a good seed yield, which is positively influenced by nitrogen fertilization and early cut application.

O presente trabalho foi desenvolvido na Estação Experimental do INIA La Estanzuela, em Colonia del Sacramento – Uruguai, de novembro de 2015 a março de 2017, com o objetivo de avaliar os parâmetros relacionados à produção e qualidade de sementes da espécie Paspalum notatum INIA Sepé. Buscou-se o entendimento dos componentes do rendimento de sementes frente a distintos níveis de fertilização nitrogenada e manejo de cortes. Foi utilizado o delineamento de blocos completamente casualizados com quatro repetições. Os tratamentos consistiram de quatro doses de fertilização nitrogenada (0, 75, 150 e 225 kg de N.ha-1) e três momentos de corte: corte precoce, corte tardio e sem corte, formando um arranjo fatorial 4x3. O padrão para realização do corte foi a fração da radiação fotossinteticamente ativa interceptada pelas plantas (50% para corte precoce e 80% para corte tardio). Para cada ano de estudo foram utilizados distintos locais dentro da mesma estação experimental a fim de avaliar a produção de sementes de plantas com idade similar (3 anos de idade), os quais foram denominados ambiente 2016 e ambiente 2017, sendo que no ambiente 2016 ocorreu maior deficiência hídrica no solo A aplicação de N possibilitou o incremento na massa de forragem, teor de proteína bruta, índice de nutrição nitrogenada e no número de perfilhos. A máxima produtividade de sementes alcançada situou-se próxima de 1000 kg.ha-1, rendimento atingido com 150 kg de N.ha-1 no ambiente 2016 e na dose 75 no ambiente 2017. Tal produtividade foi obtida com a realização de duas colheitas anuais, que foi possibilitada com a utilização de corte precoce e sem corte. Com o uso de corte tardio, por outro lado, foi possível a realização de apenas uma colheita anual, o que determinou menor rendimento total de sementes, porém possibilitou maior rendimento em apenas uma colheita. Com relação ao potencial germinativo das sementes, observamos que em situações de déficit hídrico, as plantas com suprimento de N comprometem a qualidade de sementes e favorecem o crescimento vegetativo, no caso de colheitas precoces. Por outro lado, a germinação foi melhorada quando aplicado nitrogênio associado ao corte tardio. Dessa forma, conclui-se que o ecótipo Paspalum notatum INIA Sepé possui bom rendimento de sementes, o qual é positivamente influenciado pela fertilização nitrogenada e aplicação de corte precoce. / The present work was developed at the INIA La Estanzuela Experimental Station, in Colonia del Sacramento, Uruguay, from November 2015 to March 2017, with the objective of evaluating the parameters related to the production and quality of seeds of the specie Paspalum notatum INIA Sepé. We aimed understanding of the components of the seed yield under different levels of nitrogen fertilization and cutting management. A completely randomized block design with four replications was used. The treatments consisted of twelve factorial combinations of nitrogen fertilization doses (0, 75, 150 and 225 kg of N.ha-1) and three cutting times: early cut, late cut and no cut, totaling a factorial arrangement 4x3. The standard for cutting was the fraction of the photosynthetically active radiation intercepted by the plants (50% for early cutting and 80% for late cutting). For each year of study, different locations were used within the same experimental station in order to evaluate the seed production of plants with similar age (3 years old), which were named environment 2016 and environment 2017, wherein in the environment 2016 occurred greater soil water deficit The application of N promoted the increase in forage mass, crude protein content, nitrogen nutrition index and the number of tillers. The maximum seed yield reached was close to 1000 kg.ha-1, yield reached with 150 kg of N.ha-1 in the environment 2016 and at dose 75 in the environment 2017. Such productivity was obtained by performing two harvests annually, which was possible by the use of early cutting and uncut treatments. However, with late cutting was possible to perform only one annual harvest, which resulted in lower total seed yield, but with a higher yield in only one harvest. Regarding to the seed germination, we observed that in situations of water deficit, plants with N supply compromise their seed quality in detriment of vegetative growth in the case of early harvests. On the other hand, the germination was improved when N was associated with late cut. In this way, we concluded that Paspalum notatum INIA Sepé ecotype has a good seed yield, which is positively influenced by nitrogen fertilization and early cut application.

O presente trabalho foi desenvolvido na Estação Experimental do INIA La Estanzuela, em Colonia del Sacramento – Uruguai, de novembro de 2015 a março de 2017, com o objetivo de avaliar os parâmetros relacionados à produção e qualidade de sementes da espécie Paspalum notatum INIA Sepé. Buscou-se o entendimento dos componentes do rendimento de sementes frente a distintos níveis de fertilização nitrogenada e manejo de cortes. Foi utilizado o delineamento de blocos completamente casualizados com quatro repetições. Os tratamentos consistiram de quatro doses de fertilização nitrogenada (0, 75, 150 e 225 kg de N.ha-1) e três momentos de corte: corte precoce, corte tardio e sem corte, formando um arranjo fatorial 4x3. O padrão para realização do corte foi a fração da radiação fotossinteticamente ativa interceptada pelas plantas (50% para corte precoce e 80% para corte tardio). Para cada ano de estudo foram utilizados distintos locais dentro da mesma estação experimental a fim de avaliar a produção de sementes de plantas com idade similar (3 anos de idade), os quais foram denominados ambiente 2016 e ambiente 2017, sendo que no ambiente 2016 ocorreu maior deficiência hídrica no solo A aplicação de N possibilitou o incremento na massa de forragem, teor de proteína bruta, índice de nutrição nitrogenada e no número de perfilhos. A máxima produtividade de sementes alcançada situou-se próxima de 1000 kg.ha-1, rendimento atingido com 150 kg de N.ha-1 no ambiente 2016 e na dose 75 no ambiente 2017. Tal produtividade foi obtida com a realização de duas colheitas anuais, que foi possibilitada com a utilização de corte precoce e sem corte. Com o uso de corte tardio, por outro lado, foi possível a realização de apenas uma colheita anual, o que determinou menor rendimento total de sementes, porém possibilitou maior rendimento em apenas uma colheita. Com relação ao potencial germinativo das sementes, observamos que em situações de déficit hídrico, as plantas com suprimento de N comprometem a qualidade de sementes e favorecem o crescimento vegetativo, no caso de colheitas precoces. Por outro lado, a germinação foi melhorada quando aplicado nitrogênio associado ao corte tardio. Dessa forma, conclui-se que o ecótipo Paspalum notatum INIA Sepé possui bom rendimento de sementes, o qual é positivamente influenciado pela fertilização nitrogenada e aplicação de corte precoce. / The present work was developed at the INIA La Estanzuela Experimental Station, in Colonia del Sacramento, Uruguay, from November 2015 to March 2017, with the objective of evaluating the parameters related to the production and quality of seeds of the specie Paspalum notatum INIA Sepé. We aimed understanding of the components of the seed yield under different levels of nitrogen fertilization and cutting management. A completely randomized block design with four replications was used. The treatments consisted of twelve factorial combinations of nitrogen fertilization doses (0, 75, 150 and 225 kg of N.ha-1) and three cutting times: early cut, late cut and no cut, totaling a factorial arrangement 4x3. The standard for cutting was the fraction of the photosynthetically active radiation intercepted by the plants (50% for early cutting and 80% for late cutting). For each year of study, different locations were used within the same experimental station in order to evaluate the seed production of plants with similar age (3 years old), which were named environment 2016 and environment 2017, wherein in the environment 2016 occurred greater soil water deficit The application of N promoted the increase in forage mass, crude protein content, nitrogen nutrition index and the number of tillers. The maximum seed yield reached was close to 1000 kg.ha-1, yield reached with 150 kg of N.ha-1 in the environment 2016 and at dose 75 in the environment 2017. Such productivity was obtained by performing two harvests annually, which was possible by the use of early cutting and uncut treatments. However, with late cutting was possible to perform only one annual harvest, which resulted in lower total seed yield, but with a higher yield in only one harvest. Regarding to the seed germination, we observed that in situations of water deficit, plants with N supply compromise their seed quality in detriment of vegetative growth in the case of early harvests. On the other hand, the germination was improved when N was associated with late cut. In this way, we concluded that Paspalum notatum INIA Sepé ecotype has a good seed yield, which is positively influenced by nitrogen fertilization and early cut application.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The expansion of forestation on grassland ecosystems has dramatically changed the landscape, as well as affected the biodiversity and the sustainability of these ecosystems around the world. Grasslands of southern South America hold high diversity and several cases of endemism, but historically are insufficiently protected in conservation units and experience drastic reduction due to cultivation of exotic trees as eucalyptus, black wattle and pine. Grasslands of Pampa biome in Brazilian territory are restricted to the state of Rio Grande do Sul, where recent estimates indicate that the grassyfields will disappear within the next few decades if the current scenario of changes in the productive matrix is maintained. In order to contribute with subsidies to conservation of grasslands ecosystems, the goal of this Dissertation was to study the spatial patterns in the distribution of herpetofauna (i.e. amphibians and reptiles), as well as environmental variables associated with native grasslands and eucalyptus plantation in the Pampa biome, Rio Grande do Sul state, Brazil. Thus, native grasslands and eucalyptus crops were characterized and compared regarding species richness, taxonomic composition, and abundance of amphibians and reptiles, using pitfall traps during eight sampling months (September 2012 to April 2013). The communities of amphibians and reptiles studied responded negatively to the replacement of native grasslands by arboreal crops because they were dominated by a few species in eucalyptus cultivation . Through nesting analysis and similarity tests, we recorded that reptiles responded strongly to habitat modification, since the community recorded in eucalypt was an impoverished subset of that recorded in native pasture, being still dominated by species commonly abundant in degraded areas. Amphibians responded strongly regarding species abundance and keenly to species richness, but did not respond to the gradient regarding taxonomic composition of the community. The environmental variables most strongly related to the pattern of segregation observed between native grasslands and eucalyptus cultivation were the percentage of low cover vegetation on soil and brightness. Our results indicate that eucalyptus forestation profoundly modify the structure of undergrowth vegetation, typical of grassland ecosystems and essential to the biology of several habitat-specialist species, including rare species. In this context, we emphasize that the habitat loss due to expanding forestation on grasslands configures a serious threat to conservation of the herpetofauna of the Pampa biome. Such effects can be minimized only after the adoption of specifically committed environmental policies to the conservation of grasslands ecosystems, until now so neglected. / A expansão da silvicultura sobre os ecossistemas campestres tem alterado dramaticamente a paisagem, bem como afetado a biodiversidade e a sustentabilidade desses ecossistemas ao redor do mundo. Os campos do sul da América do Sul detêm alta diversidade biológica e inúmeros casos de endemismos, mas historicamente são insuficientemente protegidos em Unidades de Conservação e experimentam drástica redução devido ao plantio de exóticas como o eucalipto, a acácia-negra e pinus. Os campos do bioma Pampa em território brasileiro estão restritos ao estado do Rio Grande do Sul, onde estimativas recentes apontam que estes desaparecerão dentro das próximas décadas se o corrente cenário de mudanças na matriz produtiva for mantido. A fim de contribuir com subsídios à preservação dos ecossistemas campestres, o objetivo dessa Dissertação foi estudar os padrões espaciais da distribuição da herpetofauna (i.e. anfíbios e répteis), bem como de variáveis ambientais associadas, em campo nativo e plantio de eucalipto localizados no bioma Pampa, Rio Grande do Sul, Brasil. Assim, campos nativos e cultivos de eucalipto foram caracterizados e comparados quanto à riqueza de espécies, composição taxonômica e abundância de anfíbios e répteis, utilizando armadilhas de interceptação e queda durante oito meses de coleta (setembro de 2012 à abril de 2013). As comunidades de anfíbios e répteis estudadas responderam negativamente à substituição dos campos nativos por cultivos arbóreos, pois foram dominadas por poucas espécies no cultivo de eucalipto. Através da análise de aninhamento e teste de similaridade, evidenciamos que os répteis responderam fortemente à alteração do hábitat, já que a comunidade registrada no eucalipto foi um subconjunto empobrecido daquela registrada no campo nativo, sendo ainda dominada por espécies comumente abundantes em áreas degradadas. Anfíbios responderam fortemente quanto à abundância das espécies e sutilmente quanto à riqueza específica, mas não responderam ao gradiente quanto à composição taxonômica da comunidade. As variáveis ambientais mais fortemente relacionadas ao padrão de segregação observado entre o campo nativo e o cultivo de eucalipto foram a porcentagem de vegetação rasteira recobrindo o solo e a luminosidade. Nossos resultados indicam que o cultivo de eucalipto altera profundamente a estrutura da vegetação rasteira, típica do ecossistema campestre e imprescindível à biologia de inúmeras espécies habitatespecialistas, incluindo espécies raras. Nesse sentido, enfatizamos que a perda de hábitat campestre devido à expansão da silvicultura configura séria ameaça à conservação da herpetofauna do bioma Pampa. Tais efeitos poderão ser minimizados somente após a adoção de políticas públicas ambientais especificamente comprometidas com a conservação dos ecossistemas campestres, até então negligenciados.