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The effects of streets on biodiversity is an important aspect of urban ecology, but it has been neglected worldwide. Several vegetation attributes (e.g. street tree density and diversity) have important effects on biodiversity and ecological processes. In this study, we evaluated the influences of urban vegetation-represented by characteristics of street trees (canopy size, proportion of native tree species and tree species richness)-and characteristics of the landscape (distance to parks and vegetation quantity), and human impacts (human population size and exposure to noise) on taxonomic data and functional diversity indices of the bird community inhabiting streets. The study area was the southern region of Belo Horizonte (Minas Gerais, Brazil), a largely urbanized city in the understudied Neotropical region. Bird data were collected on 60 point count locations distributed across the streets of the landscape. We used a series of competing GLM models (using Akaike's information criterion for small sample sizes) to assess the relative contribution of the different sets of variables to explain the observed patterns. Seventy-three bird species were observed exploiting the streets: native species were the most abundant and frequent throughout this landscape. The bird community's functional richness and Rao's Quadratic Entropy presented values lower than 0.5. Therefore, this landscape was favoring few functional traits. Exposure to noise was the most limiting factor for this bird community. However, the average size of arboreal patches and, especially the characteristics of street trees, were able to reduce the negative effects of noise on the bird community. These results show the importance of adequately planning the urban afforestation process: increasing tree species richness, preserving large trees and planting more native trees species in the streets are management practices that will increase bird species richness, abundance and community functional aspects and consequently improve human wellbeing and quality of life.

Despite its negative impacts on the environment and biodiversity, tree plantations can contribute to biodiversity conservation in fragmented landscapes, as they harbor many native species. In this study, we investigated the impact of Eucalyptus plantations on the taxonomic and functional diversity of ant communities, comparing ant communities sampled in managed and unmanaged (abandoned for 28 years) Eucalyptus plantations, and native Atlantic rain forests. Eucalyptus plantations, both managed and unmanaged, reduced the functional diversity and increased the similarity between ant communities leading to functional homogenization. While communities in managed plantations had the lowest values of both taxonomic and functional ant diversities, ant communities from unmanaged plantations had similar values of species richness, functional redundancy and Rao’s Q compared to ant communities from forest patches (although functional richness was lower). In addition, communities in unmanaged Eucalyptus plantations were taxonomically and functionally more similar to communities located in managed plantations, indicating that Eucalyptus plantations have a severe long-term impact on ant communities. These results indicate that natural regeneration may mitigate the impact of Eucalyptus management, particularly regarding the functional structure of the community (α diversity), although it does not attenuate the effects of long term homogenization in community composition (β diversity).

Intensive farming is associated with habitat loss, fragmentation, and high inputs of pesticides that, added to the environmental changes, are associated with increased levels of physiological stress in vertebrates. High levels of stress and pesticides stored in organisms’ body can cause several physiological and behavioral disruptions, including DNA and chromosome damages, i.e., cytogenetic endpoints, that can be used as biomarkers to detect bioaccumulation of pesticides and stress exposure. Here, we address how agricultural landscapes influence the frequency of cytogenetic endpoints in small non-flying mammals in Cerrado ecoregion. We sampled small mammals in 17 agricultural landscapes in Brazilian Cerrado, and analyzed the cytogenetic endpoints of 75 individuals from 13 different species using mouth swab to test the hypothesis that landscapes with higher habitat amount and aggregation, and low fragmentation, heterogeneity and patch shape index have lower frequency of cytogenetic endpoints. We found that habitat amount and aggregation were associated with lower frequency of cytogenetic endpoints, most likely due to smaller distance between remnant habitat patches, which can facilitate the movement of mammals in the landscape, and reduce stress and direct pesticide exposure. The number of patches, patch shape index, and landscape heterogeneity was associated with higher frequency of cytogenetic endpoints, most likely due to edge effects increasing environmental stress, which leads to higher frequency of cytogenetic endpoints. Our findings suggest the need for policies including incentives to forest and savanna restoration as a strategy that can improve remnant shape locally, increase habitat amount and aggregation, and decrease landscape heterogeneity due to the increase in habitat amount at regional scale. Such measures can help protecting small mammals’ health by minimizing environmental stressors. Additionally, targeted restoration efforts to increase aggregation among habitat patches may facilitate small mammals’ movements across landscapes, especially those with low dispersal capacity.

ContextDeclining in biodiversity in the Anthropocene is mostly a result of habitat loss due to changes in the landscape.ObjectivesHere, we address how landscape composition and configuration affect anuran diversity in agricultural landscapes in the Brazilian Cerrado ecoregion.MethodsWe sampled 29 breeding sites during the rainy season using auditory census and visual encounters to record anuran species richness, and specialist, generalist and dominant species richness. For each sampling site, we estimated eight landscape metrics at five spatial scales.ResultsWe recorded 36 species from seven anuran families, 17 habitat specialist and 19 habitat generalists. We found that aquatic habitat cover (%) and number of aquatic patches played a positive effect on both total anuran richness and richness of dominant species. However, landscape compositional heterogeneity and aquatic habitat isolation negatively influenced community rarity, and abundance of habitat specialist species. In addition, more diverse anuran communities were found in areas where the amount and number of aquatic habitat patches were greater.ConclusionsOur results emphasize the importance of maintaining high amounts of waterbodies and high aquatic habitat connectivity across the landscapes. Moreover, rare species and habitat specialist species are sensitive to landscape composition and configuration, respectively. Therefore, water body amount and connectivity must be considered in conservation plans to mitigate anuran community loss in agricultural landscapes.

Aim The persistence of large carnivore populations depends on their survival outside protected areas, where they often impact local livelihoods through livestock depredation. Understanding the impacts of human behaviour on large carnivores in shared landscapes is thus important but is often overlooked in habitat assessments or conservation planning. We employed an integrated approach that considers human behaviour and landscape structure metrics to assess the potential for human‐puma (Puma concolor) coexistence in the Chaco region, a global deforestation and defaunation hotspot. Location Argentine Dry Chaco (~490,000 km2). Methods We identified suitable puma habitat patches and movement areas using occupancy modelling and combined it with a spatial human‐puma conflict risk model based on interview data to identify ‘safe’ and ‘unsafe’ habitat patches. We then used resistance surfaces to identify ‘safe’ and ‘unsafe’ movement areas, as well as ‘severed’ movement areas where anthropogenic land conversion inhibits movement. Results Safe puma habitat patches (i.e., suitable and safe) covered 29% of the region, whereas attractive sinks (i.e., suitable but risky) represented 12%. Movement areas corresponded to 60% of the region, while conflict risk and high landscape resistance undermined connectivity: unsafe and severed movement areas covered 10% and 11% of the region, respectively. Nearly 98% of safe habitat and movement areas occurred outside protected areas. Main Conclusions We provide an integrated conceptual framework and spatial explicit template for a three‐pronged conservation strategy to (1) protect safe habitat and movement areas, (2) mitigate livestock depredation in attractive sinks and unsafe movement areas and (3) restore landscape in severed and matrix areas to improve ecological connectivity. This would allow pumas to maintain viable populations while reducing negative impacts on local people. More generally, we show how integrating habitat and conflict risk models can reveal opportunities and challenges for human‐carnivore coexistence beyond protected areas.

Determining the distribution and abundance of populations is the first step toward assessing biodiversity conservation status. This step is based on field observations that are largely influenced by the sampling method employed. Autonomous Recording Units (ARUs) are tools developed to improve species monitoring that employ acoustic communication. Although largely employed, the efforts required to achieve good diversity estimates with this technique are still unknown. We investigate the use of ARUs in estimating species richness of anuran assemblages in a tropical region, aiming to determine the sampling sufficiency of species richness at local and regional levels, analyze whether the asymptote point is related to forest cover, and investigate the influence of subsampling type over time on species richness estimates. We monitored amphibians in 14 streams embedded in landscapes representing a gradient from 20 to 70% native forest coverage. We detected a total of 14 species, with the regional sampling sufficiency of total species richness reached in 3448 min and influenced mainly by the terrestrial species’ presence. Forest coverage had no influence on the minimum audio processing time required to achieve local asymptote. The subsampling schemes (temporally stratified and randomly assigned) had similar efficiency when using 5 min/h or more sample efforts. Our findings indicate that passive acoustic monitoring can adequately represent local anuran richness, focusing especially on the arboreal guild. Sampling effort can be optimized, with a 5 min/h duty cycle being sufficient to recover detection of most species, saving up to 75% of the effort devoted to auditing the acoustic dataset.

Fil: Camino, Micaela. Proyecto Quimilero, Resistencia; Argentina.

Cocoa is an important agricultural product that plays a crucial role in local communities in South America. In Brazil, it is traditionally grown in agroforestry systems, which are more sustainable and contribute to biodiversity conservation. However, the recent expansion of intensive monocultures in tropical forests poses significant threats to this activity. Using historical data on land use and cocoa productivity at the municipality level from Brazil’s primary cocoa-producing states, we show that maintaining and restoring forest cover are positively correlated with cocoa productivity, particularly in areas with less anthropogenic disturbance. This highlights the dependence of cocoa production on ecosystem services. Recent data reveal that in municipalities where local agriculture is less reliant on cocoa, only larger farms have benefitted from increased forest cover, probably due to their greater dependence on fragments of natural habitat for ecosystem services. In municipalities that are more reliant on cocoa, the effects of forest cover were not detected, while strong negative effects of forest fragmentation were observed in both small- and large-scale farms. We emphasize the importance of preserving natural forests near cocoa plantations to optimize productivity in Amazon and Atlantic Forest agroforestry, especially in deforested areas.

The Edge Influence is one of the most pervasive effects of habitat fragmentation, as many forest remnants in anthropogenic landscapes are within 100 m of edges. Forest remnants may also affect the surrounding anthropogenic matrix, possibly resulting in a matrix–edge–remnant diversity gradient for some species groups. We sampled dung beetles in 15 agricultural landscapes using pitfall traps placed along transects in matrix–edge–remnant gradients. The remnants were a native savanna-like vegetation, the cerrado , and the matrix was composed of three human-dominated environments (sugarcane, eucalyptus, pasture). More species were observed in cerrado remnants than in adjacent land uses. Dung beetles were also more abundant in the cerrado than in the landscape matrix of sugarcane and eucalypt, but not of pasture. Dung beetles were severely affected by anthropogenic land uses, and notwithstanding their high abundance in some land uses such as pasture, the species richness in these areas tended to be smaller than in the cerrado remnants. We also found that the influence of the edge was evident only for abundance, particularly in landscapes with a pasture matrix. However, this land use disrupts the species composition of communities, indicating that communities located in cerrado and pasture have a distinct species composition, and that both communities are affected by edge distance. Thus, anthropogenic land uses may severely affect dung beetles, and this impact can extend to communities located in cerrado remnants as well as to those in matrices, with possible consequences for ecological processes such as decomposition and nutrient cycling.

The spatial distribution and dispersion of mercury (Hg) is associated with the structural conditions of the environment, primarily land use and vegetation cover. Man-made emissions of the metal from activities such as artisanal and small-scale gold mining (ASGM) can influence this distribution. Forest ecosystems are of particular importance as they constitute one of the most active environments in the biogeochemical cycle of Hg, and understanding these dynamics is essential to better understand its global cycle. In this study, we determined the content of Hg present in different forest strata (soil, leaf litter, herbaceous, underwood/bush, and arboreal), as well as the relationship between the presence of Hg and the landscape heterogeneity, percentage of gold mines, and ground slope. This study was carried out in tropical forest areas of the southern Brazilian Amazon. Accumulation and transport of Hg between forest strata was assessed in order to understand the influence of these forest environments on Hg accumulation in areas where ASGM occurs. We verified that there is a difference in Hg content between forest strata, indicating that atmospheric Hg is accumulated onto the arboreal stratum and transported vertically to strata below the canopy, i.e., underwood/bush and herbaceous, and subsequently accumulated in the leaf litter and transferred to the soil. Leaf litter was the stratum with the highest Hg content, characterized as a receptor for most of the Hg load from the upper strata in the forest. Therefore, it was confirmed that Hg accumulation dynamics are at play between the areas analyzed due to the proximity of ASGMs in the region. This indicates that the conservation of forest areas plays an important role in the process of atmospheric Hg deposition and accumulation, acting as a mercury sink in areas close to man-made emissions.