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851.

Context

The conversion of natural environments into agricultural land has profound effects on the composition of the landscape, often resulting in a mosaic of human-altered and natural habitats. The response to these changes may however vary among organisms. Bats are highly vagile, and their requirements often imply the use of distinct habitats, which they select responding to both landscape and local features.

Objectives

We aimed to identify which features influence bat richness and activity within Baixo Vouga Lagunar, a heterogeneous landscape located on the Central-North Portuguese coast, and to investigate if that influence varies across a gradient of focal scales.

Methods

We sampled bats acoustically, while simultaneously sampling insects with light traps. We assessed the relationships between species richness, bat activity, and activity of eco-morphological guilds with landscape and local features, across four scales.

Results

Our results revealed both scale- and guild-dependent responses of bats to landscape and local features. At broader scales we found positive associations between open-space foraging bats and habitat heterogeneity and between edge-space foraging bats and greater edge lengths. Woodland cover and water availability at an intermediate scale and weather conditions and insect abundance at a local scale were the factors that mostly influenced the response variables.

Conclusions

Globally, our results suggest that bats are sensitive to local resource availability and distribution, while simultaneously reacting to landscape features acting at coarser scales. Finally, our results suggest that the responses given by bats are guild-dependent, and some habitats act as keystone structures for bats within this mosaic.
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852.
The cover image is based on the Research Article Nonanal, a new fall armyworm sex pheromone component, significantly increases the efficacy of pheromone lures by Ahmed M. Saveer et al., https://doi.org/10.1002/ps.7460 . Image Credit: Matt Bertone.

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853.
Brazil is the world's largest producer of common beans (Phaseolus vulgaris L.). Drought stress harms the morphological and agronomic traits of beans. This study evaluates the reaction to water deficit in five genotypes of black beans. The experiment was conducted in the IDR-IAPAR-EMATER in Londrina-PR, Brazil. A split-plot design was used, with three replications. The genotypes were included in the subplots and the treatments with or without water deficit in the plots. Water deficit was induced on the pre-flowering stage and maintained for 20 days in the plots submitted to drought stress. For the growth analysis, plants were collected at 35, 54 and 70 days after emergence. At the stage of physiological ripeness, several morphological and yield traits were evaluated. The genotypes IPR Uirapuru and BRS Esplendor can be considered tolerant and used as a tolerant source to water deficit in common bean germplasm banks. The line LP 08-90 has morphological and agronomic adaptations efficient to overcome water deficit's effects, presenting a higher grain yield in both crop conditions, which indicates the success of black beans breeding to deal with water deficit.  相似文献   
854.
Structural habitat complexity provided by macrophytes is expected to increase richness and abundance of fish species. However, this topic is rarely investigated simultaneously at different periods of fish development. We sampled fish within macrophyte stands and in non-vegetated areas at floodplain lakes and tested the hypothesis that the presence of macrophytes increases abundance and species richness of fish, in addition to changes in species composition, at different periods of fish development. Our findings demonstrated that, in different period of fish development, the highest values of fish species richness and abundance were found at sites colonised by macrophytes. Similarly, changes in fish species composition were observed between habitats colonised by macrophytes and non-vegetated areas. Therefore, the results demonstrate that macrophyte presence plays an important role in regulating fish community structure at different periods of fish development.  相似文献   
855.
  1. Bivalves are important components of freshwater ecosystems; however, they are also one of the most threatened animal groups, especially members of the order Unionida. The main threats to freshwater bivalves are habitat modification and invasive species. Protected areas are a common way to minimize impacts and preserve native species, but they are rarely designated with a focus on freshwater invertebrates.
  2. The main goal of this article was to describe the distribution of freshwater bivalves in the state of Rio de Janeiro, and the relationship between these species and bioclimatic areas, land use and protected areas.
  3. Five native and two invasive bivalve species have been reported in Rio de Janeiro. They occur mainly in bioclimatic areas related to the Paraíba do Sul River and Campista Lowlands. The few records of bivalves inside protected areas are in areas of sustainable use that offer a lower level of protection, and frequently in sympatry with invasive bivalves.
  4. Thus, the established protected areas in Rio de Janeiro are not adequately effective for freshwater bivalve conservation, and some species remain under threat even within them. Freshwater bivalves thus remain largely unprotected in the state.
  5. The development of new protected areas and management plans should consider other faunal groups that are usually ignored, such as freshwater bivalves, to achieve more inclusive and effective protection.
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