Protecting riparian vegetation around streams is vital in reducing the detrimental effects of environmental change on freshwater ecosystems and in maintaining aquatic biodiversity. Thus, identifying ecological thresholds is useful for defining regulatory limits and for guiding the management of riparian zones towards the conservation of freshwater biota. Using nationwide data on fish and invertebrates occurring in small Brazilian streams, we estimated thresholds of native vegetation loss in which there are abrupt changes in the occurrence and abundance of freshwater bioindicators and tested whether there are congruent responses among different biomes, biological groups and riparian buffer sizes. Mean thresholds of native vegetation cover loss varied widely among biomes, buffer sizes and biological groups: ranging from 0.5% to 77.4% for fish, from 2.9% to 37.0% for aquatic invertebrates and from 3.8% to 43.2% for a subset of aquatic invertebrates. Confidence intervals for thresholds were wide, but the minimum values of these intervals were lower for the smaller riparian buffers (50 and 100 m) than larger ones (200 and 500 m), indicating that land use should be kept away from the streams. Also, thresholds occurred at a lower percentage of riparian vegetation loss in the smaller buffers, and were critically lower for invertebrates: reducing only 6.5% of native vegetation cover within a 50‐m riparian buffer is enough to cross thresholds for invertebrates. Synthesis and applications. The high variability in biodiversity responses to loss of native riparian vegetation suggests caution in the use of a single riparian width for conservation actions or policy definitions nationwide. The most sensitive bioindicators can be used as early warning signals of abrupt changes in freshwater biodiversity. In practice, maintaining at least 50‐m wide riparian reserves on each side of streams would be more effective to protect freshwater biodiversity in Brazil. However, incentives and conservation strategies to protect even wider riparian reserves (~100 m) and also taking into consideration the regional context will promote a greater benefit. This information should be used to set conservation goals and to create complementary mechanisms and policies to protect wider riparian reserves than those currently required by the federal law.

Há carência de estudos de inventários sobre opiliões em campos de altitude no Brasil, portanto, o presente trabalho objetivou ampliar informações sobre a opiliofauna desse ecossistema no município de Poços de Caldas, Minas Gerais. As coletas foram realizadas no período noturno, com quatro campanhas entre os meses de novembro de 2020 a março de 2021, totalizando 16 dias com 48 horas de esforço amostral. Foram coletadas quatro espécies e uma morfoespécie, que somam dois novos registros para a região, Mischonys squalidus Bertkau (Opiliones: Gonyleptidae) e Sclerosomatidae gen. sp. 1, ampliando a fauna de opiliões em campos de altitude do município para 11 espécies e uma morfoespécie.

Aim To test how different taxonomic and functional groups of aquatic insects from high-altitude streams respond to environmental and spatial gradients at multiple scales in Southeast of Brazil. Methods Specimens were collected in 26 high-altitude streams distributed over a gradient of previously defined environmental quality. The taxonomic identification was made at the genus level and the functional classification was based on traits of flight capacity and pollution tolerance compiled from specific literature. We obtained local in situ data (limnological, sediments, and organic matter), as well as calculated land use at the riparian and drainage basin scale. A variation partitioning approach was used to explain species composition based on different response matrices deconstructed by both taxonomic groups and functional traits. The explanatory matrices encompassed environmental variables at three spatial scales and spatial variables extracted from Principal Components of Neighbor Matrices analysis. A linear model was applied to verify the possible correlation between spatial and environmental components. Results The contribution of the spatial and environmental components varied strongly between taxonomic and functional groups. For taxonomic groups, the pure environmental component was more important for Odonata and Trichoptera, while spatial variables were more important for Diptera (non-Chironomidae) and Chironomidae, Coleoptera, Ephemeroptera, Plecoptera and Megaloptera. The sensitive groups with good flight capacity showed a greater environmental signature while the tolerant groups with low flight capacity had a greater spatial signature. Moreover, the important variables for explaining community variation were from different spatial scale (local, riparian and watershed) depending either on the analyzed taxonomic or on functional groups. However, a general effect of forests was found in several groups. Conclusions It is necessary to consider the joint effect of evolutionary natural history of groups, as well as their functional traits in the structuring of metacommunities, since only taxonomic resolutions may not be sufficient to detect assembly processes at multiple spatial scales.

In Brazil, there is little information about social wasp communities in Altitude Fields (Campos de Altitude), a phytophysiognomy of the Atlantic Forest with a high rate of endemism, which is being altered and reduced in area by human activities, such as the cultivation of Eucalyptus spp. Therefore, the present study aimed to inventory the species of Polistinae (Vespidae) presente in an Altitude Field associated with Eucalyptus sp. plantations in the municipality of Poços de Caldas, Southern Minas Gerais, Brazil. The study was conducted in Morro do Ferro, central region of the Poços de Caldas Plateau, from 2020 to 2021, using active search and Malaise traps. Thirteen species of social wasps were recorded, which have a wide geographic distribution, and explore anthropic environments, such as agricultural areas, pasture and Eucalyptus sp. plantations. Many of them behave as synanthropic, suggesting this altitude field to be a degraded area in Poços Caldas, MG. However, further studies must be carried out in the region, in order to know and preserve these remaining ecosystems.

Issues referring to environmental conservation and diagnosis of rural zones are still scarce topics inside public policies and this aspect still requires greater attention. That being, the goal of this research was to present a diagnosis of the rural area of a small city in the South of the Minas Gerais State, with typical agricultural characteristics and large availability of water in order to verify possible socio-environmental inconsistencies. The data was gathered from secondary information of the federal, state, and town public databases, besides face-to-face questionnaires, rapid assessment protocols and high-definition satellite mapping of land use for the last few years. It was possible to assess that conservation actions and Permanent Preservation Areas (APPs) are reduced and that interviewed people present limited knowledge about public policies of family farming stimulation. As per rural basic sanitation, practical action by local governments must be prioritized. The conclusion of this diagnosis is to suggest that further investments should be prioritized to assist social and environmental segments.