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This work investigates the removal of Brilliant Green (BG) using ZIF-67- and ZIF-8-based structures as heterogeneous photocatalysts. To further explore catalytic enhancement, Fe3O4 nanoparticles were incorporated into the ZIF structure to evaluate their contribution to the photo-Fenton process. XPS analysis identified characteristic bands corresponding to Co-N, Zn-N, and C-N bonds, along with Fe-O. Diffuse reflectance spectroscopy revealed different distinct band-gap energy transitions in the ZIF-based spectra, supporting the coordination effect of metal ions with the ligand. Incorporation of 4.0 wt% Fe3O4 into ZIF structure significantly enhanced BG degradation, achieving 100% removal under photo-assisted Fenton conditions. In the Fe3O4@ZIF-67 system, the interfacial charge-transfer dynamics follow a Z-scheme arrangement, whereas the Fe3O4@ZIF-8 operates through a conventional type-II heterojunction. The O2•– was the primary reactive species responsible for the pollutant degradation. BG dye removal in the presence of real water matrices showed minor interference from naturally occurring ions, combined with the partial mineralization achieved. Using sunlight as an energy driver, the optimized system exhibited effective BG dye removal, and the ecotoxicity assay an indication of the treatment's impact on the resulting solution. Fe3O4@ZIF composites demonstrated catalytic stability over consecutive degradation cycles, as evidenced by the absence of significant spectral changes in FTIR analysis after use. The heterojunction between Fe3O4 and ZIF structures demonstrated excellent efficiency, making them promising candidates for practical use in real-world wastewater treatment systems. Overall, the robust performance, stability, and solar responsiveness of the photocatalysts highlight its broader environmental significance as a scalable solution for advanced pollutant remediation.
Fragmentation and degradation have profound effects on species’ habitat use and activity patterns. According to their diel activity guild, species may respond differently to environmental change, with diurnal species expected to be more vulnerable to these changes. Here, we test this hypothesis by investigating how fragmentation, and degradation modulate the habitat use and overlap in diel activity of contrasting mammal diel activity guilds in the Amazonian arc of deforestation. We used data from camera-traps (2,970 trap-days) across 30 forest fragments (from 8 to 435 ha) and three continuous forest sites. Considering diurnal and nocturnal mammals separately, we examine (1) the effects of fragmentation, and degradation on the habitat use and (2) the overlap in their diel activity across the different forest sizes. Habitat use by diurnal mammals increased with forest size, but not that of nocturnal species. In general, diurnal mammals anticipate their peak activity from 00:00 h to 6:00 h into smaller fragments (< 100 ha). The diel activity patterns of diurnal mammals in small (< 50 ha) and large (< 500 ha) fragments were diverged to those in continuous forest. On the other hand, the diel activity patterns of nocturnal mammals across all size categories showed high overlap with those in continuous forest, indicating that diel activity patterns remained constant along the forest-size gradient. Such behavioral responses of diurnal mammals may be due to changes in fragment size, which alter the temporal availability of trophic resources and, consequently, may increase interspecific competition for limited resources. These findings comprise baseline knowledge informing evidence-based mechanisms of mammalian adaptation in human-modified regions across the tropics.
Extreme drought and wildfires have affected the world’s largest continuous floodplain, the Pantanal. Understanding biodiversity responses to these disturbances is essential to inform management and conservation actions aimed at maintaining ecological processes and functions. We evaluated the effects of fire on bird assemblages and their short-term recovery in a protected area the Taiamã Ecological Station encompassing swamp and marsh habitats. We compared the taxonomic and functional diversity and species composition before and after fire across three degrees of exposure (directly, indirectly and not affected by fire) and at different times since fire, using a generalized linear mixed models and beta diversity indices. Species richness and abundance increased after fire, particularly in marsh habitats. Changes in composition were stronger for sites directly affected, with high turnover of species and functional traits. Although trait turnover decreased with time since fire, functional trait composition has not returned to pre-fire levels. In sites not affected, functional richness increased in marshes but declined in swamps during the post-fire cycle. Functional evenness declined after fire in both directly and indirectly affected sites across habitats. The post-fire increase in diversity likely reflects the high conservation status of the area, including fire-suppression actions that provided refuges, as well as the emergence of new habitats for colonization that may attracted opportunistic predators. However, reduced functional evenness suggests increased niche overlap and potential competition for resources, which may negatively affect species specialized in inland wetlands. We highlight the importance of integrated fire management and long-term monitoring to assess biodiversity recovery.
Abstract Mustelids and other terrestrial carnivores use communal latrines where feces and urine serve as olfactory cues for territory demarcation and intraspecific communication. These strong scent cues may also influence the broader vertebrate community, either acting as an attractant for species in search of food or as a warning of predator presence. To investigate these effects, we compared vertebrate diversity, richness, and use characteristics at giant otter (Pteronura brasiliensis) latrine sites to background levels within Taiamã Ecological Station and surrounding areas in the Brazilian Pantanal. We deployed 35 motion‐activated camera traps across two sessions from August 2021 to November 2022. Giant otters were observed at 10 camera sites, and we observed the initiation of seven latrines. This allowed us to implement a Before‐After Control‐Impact (BACI) design, comparing each site after latrine initiation to both pre‐latrine initiation and to control sites. Across all sites, we recorded 2593 vertebrate detections, including 743 giant otter records. Species richness was slightly higher at latrine sites, but diversity decreased using indices emphasizing evenness, indicating increased dominance by a few common species. Vertebrate activity, especially among scavenging birds such as southern crested caracaras (Caracara plancus), black vultures (Coragyps atratus), and lesser yellow‐headed vultures (Cathartes burrovianus), increased significantly following latrine establishment. We documented southern crested caracaras consuming feces, sometimes while the otters were still at the latrine, highlighting latrines as transient but important food resources. While community composition did not differ significantly between latrine and control sites, these findings suggest that giant otter latrines can temporarily reshape vertebrate activity patterns and reduce community evenness. As giant otter populations continue to recover, the ecological significance of their latrines may increase, with implications for species interactions and species monitoring in the Neotropics.
Cowpea (Vigna unguiculata (L.) Walp.) is a crop of socioeconomic importance in Brazil, as it serves as a food source and generates employment and income. Cowpea is grown in large areas in the main grain-producing regions of Brazil and has been a good option for the second crop season due to its high tolerance to water deficit. The objective of this study was to select parental lines based on genetic divergence assessed using inter-simple sequence repeat (ISSR) molecular markers and grain yield for cowpea breeding. Genomic DNA was extracted from 14 lines and six cultivars, and amplifications were performed using ten ISSR molecular markers. Genetic diversity was estimated using Nei's gene diversity index and Shannon's information index. Pairwise genetic comparisons were based on Jaccard's similarity coefficient, and genotypes were grouped using Tocher's clustering method and unweighted pair group method with arithmetic mean (UPGMA). A total of 105 fragments were amplified, of which 99.05% were polymorphic. Nei's genetic diversity index was 0.2651, and Shannon's information index was 0.4178. Genetic dissimilarity values among genotypes ranged from 0.24 to 0.85. The smallest genetic distance was observed between genotypes MNC11-1022E-9 and MNC11-1031E-11, and the largest between genotypes MNC11-1015E-35 and Pingo de Ouro 1-5-14. The UPGMA clustering method formed five distinct groups, whereas Tocher's clustering method formed six groups. Genetic diversity exists among the evaluated genotypes, indicating potential for selecting contrasting parental lines for use in crosses aiming at breeding various commercial classes and subclasses of cowpea.
