Taliane Maria da Silva Teófilo

The use of metals is widespread across industries such as electroplating, leather tanning, and agriculture. The frequent detection of metal ions in water bodies has raised environmental concerns, prompting the search for effective remediation technologies. This study evaluated the potential of banana peel-derived bioadsorbents (biomass, hydrochar, basic hydrochar, and acid hydrochar) to remove hexavalent chromium [Cr (VI)] from water and examined the impact of adsorption residue on cement mortar properties. Acid hydrochar exhibited the highest Cr (VI) removal capacity at 5.81 mg g-1 (81.1%), followed by hydrochar (4.24 mg g-1, 59.2%), basic hydrochar (3.51 mg g-1, 48.9%), and biomass (2.77 mg g-1, 38.6%). Adsorption kinetics showed that the OG model best fit the data for biomass, while hydrochar and acid hydrochar aligned more closely with the Avrami model. At equilibrium, biomass and hydrochar followed the Freundlich model, whereas acid hydrochar fit the Langmuir model. Desorption was minimal for all bioadsorbents. Cement mortar analysis revealed that increasing acid hydrochar substitution reduced workability and mechanical strength (flexural and compressive). However, higher concentrations decreased capillary absorption due to the pore-buffering effect. No significant differences were observed between reference mortar and mortar with 1% substitution. The study highlights the effectiveness of bioadsorbents, particularly acid hydrochar, in Cr (VI) removal and its potential as a sustainable alternative for partial cement replacement at up to 1%, balancing environmental and material performance benefits.

Brazil is among the four largest global food producers and is a significant consumer of pesticides. However, the current management of pesticide residues in Brazil faces substantial challenges, including fragmented data, limited access to reliable information, and weak inter-institutional coordination. These shortcomings hinder effective monitoring and enforcement. This study evaluates the existing framework for managing pesticide residues in food, water, and soil in Brazil, identifying gaps and proposing strategies for improvement. Key recommendations include the establishment of an inter-institutional steering committee, the development of a unified digital platform for data sharing, and the implementation of a National Pesticide Residue Management Programme (NPRMP). The NPRMP would define measurable targets to reduce contamination in food and the environment, promote sustainable agricultural practices, and enhance the monitoring of pesticide residues. Capacity-building through continuous professional training and public education campaigns is essential to ensure the programme’s successful implementation. Financial resources may be drawn from various sources, including budgetary allocations by the federal government; donations from individuals or legal entities, whether public or private, domestic or international; funds from the National Fund for Scientific and Technological Development (FNDCT); and contributions from the National Environmental Fund. This integrated approach aims to reinforce regulatory mechanisms, safeguard public health, and ensure environmental conservation within the context of Brazil’s expanding agricultural sector.

Growing lettuce in a shaded environment in the semiarid region has become an alternative to creating an ideal microclimate for crop development. However, this microclimate also favors weed development. Therefore, the objective of this study was to evaluate the effect of the reduction in luminosity caused using shading screens on the critical period of interference prevention (CPIP) in organic lettuce cultivation. Two experiments were carried out in randomized blocks with three replications in a split-plot design. The first experiment was conducted under full light conditions and the second in a shaded environment with a 35% reduction in light intensity. Shading altered the dynamics of weeds, with Digitaria horizontalis Willd and Amaranthus spinosus L. having the highest density in crops without cover and shaded environments, respectively. The lack of weed control reduced lettuce productivity by 66 and 90% in uncovered and shaded systems, respectively. The CPIP of lettuce in an uncovered environment occurred 11–33 and 12–28 days after transplant (DAT) considering an acceptable production reduction of 2.5 and 5%, respectively. The shaded environment decreased the CPIP of lettuce to 8–19 and 9–18 DAT for acceptable production reductions of 2.5 and 5%, respectively. Therefore, growing organic lettuce in a shaded environment allows for a shorter control period.

The use of screened structures is an alternative for reducing light, creating an ideal microclimate for vegetable development. In this sense, the objective of this research was to evaluate the effect of shading caused by the protected environment on the dynamics and period of weed control in organic arugula crops. Two experiments were carried out using a randomized block design with three replications in a split-plot scheme. The first experiment was conducted under full light conditions, and the second experiment was conducted in a shaded environment with a 35% reduction in light. The Digitaria horizontalis Willd and Amaranthus spinosus L. having the highest density in the uncovered system and the protected environment, respectively. The lack of weed control reduced arugula productivity by 52 and 80% in systems with and without a protected environment, respectively. The critical interference prevention period (CIPP) for arugula in an uncovered environment was 8–29 and 8–26 days after transplant (DAT), considering an acceptable production reduction of 2.5 and 5%, respectively. The protected environment reduced the CIPP of arugula to 20–39 and 20–31 DAT for acceptable production reductions of 2.5 and 5%, respectively. The use of the protected environment changed the dynamics of the species and reduced the period of weed control in organic arugula by 3 and 8 days, considering an acceptable production reduction of 2.5 and 5%, respectively.

Background: Knowing the relationships between the soil’s physical-chemical properties and herbicide behavior in the soil allows establishing strategies for the efficient control of weeds with less environmental risk. Objective: It carried this study to investigate the role of physical-chemical properties of Brazilian soils in the sorption-desorption and mobility of the herbicide saflufenacil. Methods: We used nine soils from different regions of Brazil in the study of sorption-desorption and mobility of 14C-saflufenacil. The herbicide sorption-desorption estimate was performed using the [...] Background: Knowing the relationships between the soil’s physical-chemical properties and herbicide behavior in the soil allows establishing strategies for the efficient control of weeds with less environmental risk. Objective: It carried this study to investigate the role of physical-chemical properties of Brazilian soils in the sorption-desorption and mobility of the herbicide saflufenacil. Methods: We used nine soils from different regions of Brazil in the study of sorption-desorption and mobility of 14C-saflufenacil. The herbicide sorption-desorption estimate was performed using the

The leaching of herbicides into the soil is essential to control germinating seeds and parts of vegetative weeds. However, herbicide transportation to deeper soil layers can result in groundwater contamination and, consequently, environmental issues. In this research, our objective was to investigate differences in herbicide leaching between commercial formulations and analytical standards using three different soils. Leaching experiments were carried out for diuron, hexazinone, and sulfometuron-methyl herbicides isolated and in binary and ternary mixtures. The herbicide residue quantification was performed by ultra-high-performance liquid chromatography coupled to a mass spectrometer (LC-MS/MS). Diuron had less mobility in soils and was retained in the most superficial layers. Hexazinone and sulfometuron-methyl were more mobile and leached into deeper layers. The leaching process was more intense for hexazinone and sulfometuron-methyl. The additives present in the commercial formulation favored the leaching in soils of diuron, hexazinone, and sulfometuron-methyl herbicides isolated and mixture compared to the analytical standard. This fact highlights the importance of considering these effects for the positioning of herbicides in the field to increase the efficiency of weed control and minimize the potential for environmental contamination.

The management of weeds in melon is hindered by the slow initial growth of the crop, favouring weed infestation and reducing production. During the years 2016 and 2017, weed interference periods were evaluated in two melon hybrids, yellow and frog skin, to determine the time of weed control in the crop. Four-parameter logistic regression was used to determine the critical weed control period (CPWC). The weed species with the highest occurrences in 2016 were Merremia aegyptia, Senna obtusifolia, and Urochloa plantaginea. In 2017, there was a predominance of M. aegyptia, indicating the possibility of successive cultivation, favouring the predominance of species with growth habits similar to melons. The increase in the period of living with weeds reduced the productivity and quality of melon fruits. Coexistence with weeds throughout the cycle reduced productivity by about 50%. The CPWC was 15 to 58 and 10 to 45 for frog skin and 12 to 52 and 4 to 50 days for yellow melon in 2016 and 2017, respectively, considering a productivity loss of 5%. These results underscore the importance of adopting strategies that allow melons to grow free from the presence of weeds, especially before they are fully established in the growing area.

Weed interference is one of the factors that reduces carrot yield considerably. The aim of this study was to determine the periods of weed interference in carrots cultivated under two localized irrigation systems. The experiment used a completely randomized block design, with three replications, using the split plot scheme. The plots consisted of two irrigation systems (drip and micro sprinkler) and the subplots corresponded to the duration of coexistence of the crop with weeds, comprising periods of control (weed -free) or coexistence (with weeds) (0, 10, 20, 30, 40, 50, and 120 days after emergence (DAE) of the crop). Considering a yield loss of 2.5%, 5%, and 10% in marketable carrots, the beginning and end of the critical period of weed control (CPWC) was determined by adjusting a sigmoid model to the relative production data. The presence of the weed community throughout the crop cycle resulted in yield losses of up to 98%. The CPWP varied for the irrigation systems used. Carrot cultivation with and without competition, under the micro sprinkler irrigation system showed a higher yield than with the drip system. Considering a yield loss of 5%, the CPWC was 23 DAE and 7 DAE in the drip irrigation and micro sprinkler irrigation systems, respectively.