Reference values and drivers of diversity for South Brazilian grassland plant communities

Abstract

The South Brazilian grasslands (Campos Sulinos) form the dominant vegetation in southern Brazil. They are species-rich ecosystems that occur under distinct geomorphological and climatic conditions but spatial variation of plant species diversity remains understudied. Here, we present a detailed description of plant communities across the region. Our data were obtained in 1080 plots, representing well-preserved grasslands in different ecological systems. Apart from describing alpha and beta diversity, we investigated the relations of plant communities with environmental features. We identifi ed 759 plant species and found clear differences in community composition across the region. Northern and Southern highland grasslands, humid and dry coastal grasslands and the mesic Pampa grassland were clearly distinct, related to climatic and edaphic features. While species abundance distribution was markedly uneven, local species richness was high, above 20 species/m 2 , especially in the highlands and in mesic Pampa sites, on shallow soils. The predominant component of beta diversity was species turnover, which suggests that a network of well-conserved grasslands distributed across the region would be the best strategy to protect plant diversity. Our results establish regionalized reference values for richness and diversity that can be useful for initiatives of restoration and conservation of these grasslands.

Biophysical delineation of grassland ecological systems in theState of Rio Grande do Sul, Southern Brazil

“…Recent vegetation studies (in the region) confirm statements of several authors on the influence of relief and soil on the spatial distribution of herbaceous plant communities (Boldrini et al 2009, Ferreira et al 2010, 2020, Freitas et al 2010, Setúbal & Boldrini 2012, Pinto et al 2013, Menezes et al 2015, Andrade et al 2016, 2019, Menezes et al 2022. Andrade et al (2019) refers to 1,502 samples of 1 m² of the SISBIOTA Project (National System Research on Biodiversity -"Sistema Nacional de Pesquisa em Biodiversidade"), Ferreira et al (2020) refers to 262 samples of 1 m² along five years of the PELD Project (Long Term Ecological Research-South Brazilian Campos -"Pesquisas Ecológicas de Longa Duração-Campos Sulinos"), and Menezes et al (2022) refers to 1,080 samples of 1 m² of the PPBIO Project (Research Program on Biodiversity of the South Brazilian Campos -"Programa de Pesquisa em Biodiversidade nos Campos Sulinos"). Our identification of two new grassland ecological systems beyond those previously described (ASG and PAG) demonstrates the potential of geospatial analysis in the characterization of environments consistently and coherently.…”

“…Although our list of species is not comprehensive, it reflects the differentiation of each grassland in terms of floristic composition. Andrade et al (2019) classified the grasslands of Rio Grande do Sul into three types and ten subtypes, and Menezes et al (2022) into three types and four subtypes, drawing our attention to the fact that the number of sample units, for more accurate classification, has to be larger by considering the different abiotic characteristics in more detail. In this work, with biophysical variables, we directed attention to the abiotic characterization of grasslands and delimitated them into ten ecological systems.…”

Gramados Urbanos: A Surpreendente Diversidade De Espécies Encontrada No Campus Do Vale Da Ufrgs (Rs, Brasil) E Suas Potencialidades

“…Considerando a cobertura relativa, a ordem de famílias mais importantes se modifica, sendo que Poaceae, Apiaceae e Asteraceae apresentaram os maiores valores com 40%, 19% e 13% respectivamente. A alta cobertura por gramíneas é uma característica típica da vegetação campestre como evidenciado em um estudo abrangente na região dos Campos Sulinos, onde as gramíneas cobriram 64,6% da vegetação, seguidas por Asteraceae com 10,2% e Cyperaceae com 6.4% (Menezes et al 2022). A alta importância da família Apiaceae encontrada nos gramados do Campus do Vale se deve a grande participação de E. elegans na cobertura de várias parcelas, provavelmente associada com o constante distúrbio de roçada dos gramados.…”

Essential oil composition and biological activities of Aloysia gratissima (Gillies & Hook.) Tronc. (Verbenaceae): a systematic review

“…However, due to the lack of policies and appreciation of its natural and cultural heritage, this reality is strongly threatened (Fernandes et al, 2017). In this reality, the Pampa biome, located in the southern part of South America, with 193,000 km² under Brazilian rule, exclusive in Rio Grande do Sul, is currently the second most threatened biome in Brazil, mainly for the predominance of open ecosystems (MapBiomas 2022; Menezes et al, 2022;Hasenack et al, 2023).…”