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Conventional soil management in agricultural areas may expose non-target organisms living nearby to several types of contaminants. In this study, the effects of soil management in extensive pasture (EP), intensive pasture (IP), and sugarcane crops (C) were evaluated in a realistic-field-scale study. Thirteen aquatic mesocosms embedded in EP, IP, and C treatments were monitored over 392 days. The recommended management for each of the areas was simulated, such as tillage, fertilizer, pesticides (i.e. 2,4-D, fipronil) and vinasse application, and cattle pasture. To access the potential toxic effects that the different steps of soil management in these areas may cause, the cladoceran Ceriophania silvestrii was used as aquatic bioindicator, the dicot Eruca sativa as phytotoxicity bioindicator in water, and the dipteran Chironomus sancticaroli as sediment bioindicator. Generalized linear mixed models were used to identify differences between the treatments. Low concentrations of 2,4-D (<97 μg L -1 ) and fipronil (<0.21 μg L -1 ) in water were able to alter fecundity, female survival, and the intrinsic rate of population increase of C. silvestrii in IP and C treatments. Similarly, the dicot E. sativa had germination, shoot and root growth affected mainly by 2,4-D concentrations in the water. For C. sancticarolli, larval development was affected by the presence of fipronil (<402.6 ng g -1 ). The acidic pH (below 5) reduced the fecundity and female survival of C. silvestrii and affected the germination and growth of E. sativa. Fecundity and female survival of C. silvestrii decrease in the presence of phosphorus-containing elements. The outcomes of this study may improve our understanding of the consequences of exposure of freshwater biota to complex stressors in an environment that is rapidly and constantly changing., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Among the largest metropolitan regions in the world, the Metropolitan Region of São Paulo (MRSP) represents an important case study for the COVID-19 respiratory disease pandemic because it is home to >20 million people, making it one of the largest metropolitan regions in the global south. Besides the high population density, the MRSP has several problems related to social and economic aspects, which may reflect in the dynamics of SARS-CoV-2 virus, such as low income, lack of sanitation and social vulnerability in the peripheral regions of MRSP. In these regions, the input of untreated sewage on the streams and rivers can be frequently observed, which may represent an indicator of poor sewer system. Therefore, this study aimed to identify if streams draining urbanized regions without appropriate sanitation are prone to receive higher loads of detectable SARS-CoV-2 in its waters. For this, we collected water samples from 45 headwater streams distributed across an urbanization gradient (0-100 % of urbanization) in the MRSP, with three replicates in each stream and analyzed the concentrations of SARS-CoV-2 RNA targeting the nucleocapsid N1 and N2 genomic regions. In addition, we analyzed the relationship between the concentrations of SARS-CoV-2 RNA and sanitation and social variables. Our results showed that the concentrations of SARS-CoV-2 RNA were higher in the streams draining medium to high urbanized catchments, especially because of the lack of sanitation and the higher probabilities to detect SARS-CoV-2 RNA in the stream water was associated with households without a septic tank or sewage system within the catchment, followed by per capita household income. These results reflect the lack of urbanization planning and the lack of sanitation, especially in the poor regions from the MRSP, adding another risk for the already vulnerable population in a metropolitan region from the global south during a pandemic disease., Competing Interests: Declaration of competing interest Rodrigo F. Bueno reports financial support was provided by National Council for Scientific and Technological Development. Matheus Ribeiro Augusto reports financial support was provided by National Council for Scientific and Technological Development. Ricardo H Taniwaki reports financial support was provided by State of Sao Paulo Research Foundation., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Sugarcane is one of the main monocultures in Brazil and widely uses herbicide 2,4-D and fipronil insecticide. In addition, vinasse can be mentioned as it is widely used in this plantation. These compounds occurring simultaneously in the aquatic environment can potentiate the deleterious effects on organisms. Thus, this study aimed to evaluate the composition, abundance and ecological indices of the benthic macroinvertebrate community, as well as its ability to reestablish itself considering environmental contamination by the pesticides Regent® 800WG (active ingredient - a.i. fipronil) (F) and DMA® 806BR (a.i. 2,4-D) (D) and vinasse (V), alone and in mixtures: pesticides - M and the three contaminants - MV. The study was conducted using open-air mesocosms. The macroinvertebrate community was monitored by colonization structures, the physical-chemical parameters, metals and pesticides were determined and the effects of contaminants were evaluated over the exposure time in 1, 7, 14, 28, 75 to 150 days. A multiple regression was performed between the water parameters and significant relationships were found between parameters associated with vinasse contamination (pH, total nitrogen, turbidity, and dissolved oxygen) and concentration of fipronil and the ecological variables studied. Over time, changes were observed in the composition of the community. The dominance and richness increased in treatments V and MV. The family Chironomidae and subclass Oligochaeta were more sensitive to the treatment V and MV, while individuals from the families Phoridae, Ephydridae and Sciomyzidae were occasionally found (depending on the experimental time) in these treatments. The insects were sensitive to treatments F and M, disappearing in these mesocosms after contamination, reappearing only after 75 days. The results reveal that sugarcane management practices associated with the use of pesticides and vinasse as fertilizer pose risks to the macroinvertebrate community with consequences for the trophic chains, given its importance in freshwater ecosystems and adjacent terrestrial environments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

This study evaluated the effects of environmental contamination caused by pasture intensification and pasture-sugarcane conversion on oxidative stress, biotransformation, esterase enzymes, and development of Scinax fuscovarious and Physalaemus nattereri. Tadpoles were exposed in mesocosms allocated in three treatments: (1) untreated extensive pasture (EP); (2) intensive-pasture conversion (IP) (2,4-D herbicide + fertilizers); and (3) pasture-sugarcane conversion (SC) (fipronil + 2,4-D + fertilizers). After 7 days of exposure, IP reduced catalase (CAT) and increased malondialdehyde (MDA) levels in P. nattereri, while this treatment decreased glucose-6-phosphate dehydrogenase (G6PDH) and CAT activities in S. fuscovarious. SC decreased CAT, G6PDH, and glutathione S-transferase (GST) activities in P. nattereri. In S. fuscovarius, SC reduced G6PDH, acetylcholinesterase (AChE), and carboxylesterase (CbE) activities. MDA was raised in both tadpole species exposed to SC, evidencing oxidative stress. Integrated biomarker responses showed higher scores in both species exposed to SC. Our results warn that management practices currently applied to sugarcane cultivation in Brazil can negatively impact the functional responses of amphibians at natural systems., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Tropical streams have been intensively impacted by agricultural activities. Among the most important agricultural activities in Brazil, sugarcane production represents a large impact for economic development and for environmental conditions. Permeating sugarcane fields, several headwater streams can be affected by sugarcane cultivation, in special, aquatic biogeochemical cycles because of the deforestation, fertilization, crop residues and higher temperatures in the tropics. In this study, we analyzed the effects of sugarcane cultivation on methane fluxes and concentrations, assuming that carbon cycles are influenced by agricultural activities in headwater streams. Our study aimed to (1) measure methane fluxes and concentrations in tropical streams located in Southeastern Brazil, (2) Analyze whether seasonal cycles influence methane fluxes and concentrations, (3) Evaluate the influence of sugarcane cultivation on methane fluxes and (4) Analyze the association between water chemistry in the methane concentrations in tropical streams. We found mean fluxes of CH 4 of 0.280 mmol m -2 d -1 , with higher fluxes during the summer and in streams draining preserved catchments. The average CH 4 concentrations were 0.695 μmol L -1 , with higher values during the summer and in streams draining preserved catchments. Methane concentrations in the studied streams was influenced by dissolved oxygen (negatively), dissolved organic carbon (negatively), water velocity (positively) and conductivity (negatively). Methane concentrations were significantly higher than concentrations found in Temperate Grasslands, Savannas & Shrublands and similar to concentrations found in other tropical biomes (excluding Tropical & Subtropical Moist Broadleaf Forests which receives large amounts of organic inputs). We conclude that sugarcane influence methane concentrations and fluxes in tropical streams by reducing the organic matter availability provided by the native vegetation in soil and water., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Ricardo Hideo Taniwaki reports financial support, administrative support, and equipment, drugs, or supplies were provided by Federal University of the ABC. Ricardo Hideo Taniwaki reports financial support and administrative support were provided by Federal University of Sao Carlos. Ricardo Hideo Taniwaki reports administrative support and equipment, drugs, or supplies were provided by University of Sao Paulo., (Copyright © 2022 Elsevier B.V. All rights reserved.)