RESUMO

The objective of this study was to evaluate the economic and financial viability of finishing of two sexes of Brazilian Somalis sheep in feedlot receiving diets with 0 and 15% reduction in the total digestible nutrients and crude protein contents. A completely randomized design was adopted, in a 2 × 2 factorial arrangement, with treatments consisting of two sexes (non-castrated males (21.13 ± 5.00 kg) and females (17.99 ± 3.79 kg) and two diets (0 and 15% reduction in the levels of total digestible nutrients and crude protein). Four simulations of productive scenarios were carried out: non-castrated males receiving the diet with 0% reduction; non-castrated males receiving the diet with 15% reduction; females receiving the diet with 0% reduction and females receiving the diet with 0% reduction, for a period of 70 days in feedlot. The highest costs of the system were with feeding and other costs, mainly the acquisition of animals. For both sexes, the 0% reduction diet showed the highest total cost, total revenue, break-even point. Non-castrated males fed a non-reduced diet and females fed a 15% reduction diet had higher net income, rate of return, total productivity, net present value, internal rate of return, profitability index and profitability rate. Less favorable situations were not profitable for any scenario. However, the increase in sales price favorability makes the activity viable. The reduction of total digestible nutrients and crude protein affects the economic and financial viability of Brazilian Somalis sheep. For non-castrated males it is recommended the diet without reduction and for females the diet with 15% reduction of nutrients.

Assuntos

Ração Animal , Criação de Animais Domésticos , Fenômenos Fisiológicos da Nutrição Animal , Dieta , Animais , Masculino , Feminino , Brasil , Ração Animal/análise , Ração Animal/economia , Criação de Animais Domésticos/economia , Criação de Animais Domésticos/métodos , Dieta/veterinária , Dieta/economia , Carneiro Doméstico/fisiologia , Carneiro Doméstico/crescimento & desenvolvimento

RESUMO

Tropical stream ecosystems are under increasing human pressure, making the development of effective restoration approaches and expanding knowledge in this field urgent. This study evaluated the impact of riparian vegetation restoration and environmental context on stream ecosystem functioning by measuring key ecosystem functions - gross primary production (GPP), ecosystem respiration (ER), and nutrient uptake of ammonium and soluble reactive phosphorus - across ten tropical streams in southeastern Brazil. The streams represented a gradient from clearcut areas (impacted reaches) to relatively pristine conditions (reference reaches), including intermediate stages of vegetation recovery (restored reaches). In the short-term (~15-20 years after restoration), restoration led to reduced GPP akin to reference reaches. Yet, ER did not show the anticipated increase, suggesting a longer timeframe is necessary for restored streams to emulate the functional characteristics of reference reaches. Additionally, the restored reaches did not achieve the nutrient uptake efficiencies observed in both impacted and reference reaches, pointing to a partial recovery of ecosystem function. This study suggests that while riparian vegetation restoration contributes positively to certain aspects of stream function, environmental variables less related to this type of restoration, such as discharge and hydromorphology, significantly influence stream ecosystem functioning, highlighting the importance of considering environmental context in restoration efforts. A more holistic approach, possibly encompassing broader hydromorphological and habitat enhancements, is needed to fully restore ecological processes in these vital ecosystems. These insights are critical for informing future tropical stream restoration projects, advocating the use of ecosystem function metrics as comprehensive indicators of ecological recovery and restoration success.

Assuntos

Ecossistema , Monitoramento Ambiental , Recuperação e Remediação Ambiental , Rios , Brasil , Recuperação e Remediação Ambiental/métodos , Fósforo/análise , Clima Tropical , Conservação dos Recursos Naturais/métodos

RESUMO

Nature-based solutions have been proven in recent decades as a reliable and cost-effective technology for the treatment of wastewaters. Different plant species have been studied for this purpose, but particular attention has been given to duckweeds, the smallest flowering plant in the world. Duckweed-based systems for simultaneous wastewater treatment and nutrient recovery have the potential to provide sustainable and cost-effective solutions to reduce water pollution and increase nutrient efficiency at catchment level. However, despite being considered a seemingly simple technology, the performance of wastewater treatment systems using duckweed depends on environmental and operational conditions not very well understood. For that reason, careful consideration must be given to such environmental factors controlling duckweed biomass growth but the evidence in published literature is scare and dispersed. This study employs a systematic review approach to conduct a meta-analysis of the effect of environmental conditions on duckweed growth by means of standardised IQ-scores. The results suggest that duckweed biomass growth rates reach a maximum within specific ranges for temperature (11.4-32.3 °C), daily light integral (DLI) (5-20 mol m-2), and nitrogen (>5 mg N L-1) and phosphorus (>1 mg P L-1) concentrations; DLI was found to be a better parameter to assess the overall effect of light (photoperiod and intensity) on duckweed growth and that the effect of nitrogen and phosphorus supply should consider the nitrogen species available for plant growth and its ratio to phosphorus concentrations (recommended N:P ratio = 15:1). By establishing the optimal range of culture conditions for duckweed, this study provides important insights for optimizing engineered wastewater treatment systems that rely on duckweed for nutrient control and recovery, which is primarily mediated by duckweed growth.

Assuntos

Biomassa , Luz , Nutrientes , Fósforo , Temperatura , Fósforo/análise , Nitrogênio , Araceae/crescimento & desenvolvimento , Águas Residuárias

RESUMO

Modeling of watershed Ecosystem Services (ES) processes has increased greatly in recent years, potentially improving environmental management and decision-making by describing the value of nature. ES models may be sensitive to different conditions and, therefore, should ideally be validated against observed data for their use as a decision-support instrument. However, outcomes from such ES modeling are barely validated, making it difficult to assess uncertainties associated with the modeling and justify their actual usefulness to develop generalizable management recommendations. This study proposes a framework for the systematic validation of one of such tools, the InVEST Nutrient Delivery Model (NDR) for nutrient retention estimates. The framework is divided into three stages: 1) running the NDR model inputs, processes, and outputs; 2) building a long-term reference dataset from open access water quality observations; and 3) using the reference data for model calibration and validation. We applied this framework to twenty watersheds in the Commonwealth of Puerto Rico, where data availability resembles thar of watersheds across the United States. Long-term water quality data from monitoring stations facilitated model calibration and validation. Our framework provided a reproducible method to linking the vast monitoring network in the U.S. and its territories for evaluating the InVEST's NDR model performance. Beyond the framework development, this study found that the InVEST NDR model explained 62.7 % and 79.3 % of the variance in the total nitrogen and total phosphorus between 2000 and 2022, respectively, supporting the suitability of the model for watershed scale ecosystem services assessment. The findings can also serve as a reference to support the use of InVEST for other locations in the tropics without publically available monitoring data.

RESUMO

Studies indicate that ultra-processed food (UP) consumption correlates negatively with essential vitamin and mineral intake and positively with sodium and lipid intake. The objective of this study was to explore the relationship between UP consumption and deviations from nutritional guidelines. An observational, cross-sectional analytical study was conducted on a probability sample of manufacturing workers in the state of Rio Grande do Norte, Brazil. Food consumption was assessed with a 24 h recall survey, and nutrient intake inadequacies were calculated as the difference between individuals' intake of energy, macronutrients, minerals and vitamins, and the dietary reference intakes for individuals of the same sex and age group, and then analyzed for trends across the percentage contribution of UP to total energy intake with nonparametric multiple regression adjusted for covariates. The study included 921 workers from 33 industries, 55.9% male, with a mean age of 32 years. Overall, the study population exhibited deficits in energy, all macronutrients, and in some micronutrients. With increasing UP contribution to total energy intake, there is a trend towards a greater intake of energy (p < 0.001), total, saturated, monounsaturated, and trans fats (p < 0.001), n6-polyunsaturated fatty acids (p = 0.03), carbohydrates (p < 0.001), calcium (p = 0.008), and manganese (p < 0.001), thiamin (p < 0.001), and vitamin B6 (p = 0.01); however, this comes with a negative consequence in terms of reducing the protein consumption (p = 0.037), fiber (p = 0.035), copper (p = 0.033), and vitamin E (p = 0.002) intake. The results show that correcting energy and micronutrient deficiencies by increasing UP consumption can also lead to a decrease in diet quality.

Assuntos

Minerais , Nutrientes , Vitaminas , Humanos , Masculino , Feminino , Adulto , Estudos Transversais , Minerais/administração & dosagem , Vitaminas/administração & dosagem , Brasil , Adulto Jovem , Pessoa de Meia-Idade , Fast Foods/estatística & dados numéricos , Ingestão de Energia , Dieta/estatística & dados numéricos , Alimento Processado

RESUMO

Scavenging is a key process for the cycling of nutrients in ecosystems, yet it is still neglected in the ecological literature. Apart from the importance of specific groups of animals in scavenging, there have been few ecological studies that compare them. Furthermore, the ecological studies on scavenging have mainly focused on vertebrates despite the crucial importance of invertebrates in this process. Here, we performed a large-scale ant suppression and vertebrate exclusion experiment to quantify the relative contribution of ants, non-ant invertebrates and vertebrates in scavenging nitrogen-rich (insect carcasses) and carbon-rich (seeds) baits in two contrasting mountainous habitats in Brazil (grasslands and forests). Overall, bait removal was 23.2% higher in forests than in grasslands. Ants were the primary scavengers in grasslands, responsible for more than 57% of dead insect larvae and seed removal, while, in forests, non-ant invertebrates dominated, removing nearly 65% of all baits. Vertebrates had a minor role in scavenging dead insect larvae and seeds in both habitats, with <4% of removals. Furthermore, our results show that animal-based baits were more consumed in forests than seeds, and both resources were equally consumed in grasslands. Therefore, we demonstrate the superiority of invertebrates in this process, with a particular emphasis on the irreplaceable role of ants, especially in this grassland ecosystem. As such, we further advance our knowledge of a key ecosystem process, showing the relative importance of three major groups in scavenging and the differences in ecosystems functioning between two contrasting tropical habitats.

Assuntos

Formigas , Florestas , Pradaria , Invertebrados , Animais , Formigas/fisiologia , Invertebrados/fisiologia , Brasil , Comportamento Alimentar/fisiologia , Ecossistema , Insetos/fisiologia

RESUMO

Enhancing the initial stages of plant growth by using polymeric gels for seed priming presents a significant challenge. This study aimed to investigate a microgel derived from polyetheramine-poly(propylene oxide) (PPO) and a bisepoxide (referred to as micro-PPO) as a promising alternative to optimize the seed germination process. The micro-PPO integrated with an iron micronutrient showed a positive impact on seed germination compared with control (Fe solutions) in which the root length yield improved up to 39%. Therefore, the element map by synchrotron-based X-ray fluorescence shows that the Fe intensities in the seed primers with the micro-PPO-Fe gel are about 3-fold higher than those in the control group, leading to a gradual distribution of Fe species through most internal embryo tissues. The use of micro-PPO for seed priming underscores their potential for industrial applications due to the nontoxicity results in zebrafish assays and environmentally friendly synthesis of the water-dispersible monomers employed.

Assuntos

Aminas , Cucumis sativus , Germinação , Ferro , Microgéis , Sementes , Germinação/efeitos dos fármacos , Sementes/química , Sementes/metabolismo , Sementes/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Cucumis sativus/metabolismo , Cucumis sativus/crescimento & desenvolvimento , Cucumis sativus/química , Ferro/metabolismo , Ferro/química , Aminas/química , Aminas/metabolismo , Microgéis/química , Compostos de Epóxi/química , Compostos de Epóxi/metabolismo , Peixe-Zebra/metabolismo , Animais

RESUMO

Mechanically separated meat (MSM) is widely used in the food industry, however, there is a lack of studies on its consumption in populations. The objective of this study was to identify the frequency and amount of MSM consumption, factors associated with MSM consumption, nutrient intake and preferential choice of food groups among MSM consumers. This was an observational, cross-sectional prospective study based on a probability sample of manufacturing workers, conducted in Brazil. Logistic and linear multiple regression with robust standard errors were used. 921 workers from 33 manufacturing companies were studied, with an average age of 38.2 ± 10.7 years, 55.9% males. MSM products are consumed by 28.8% and represent in average 10% of total daily caloric intake, and 47.3% of the daily kcal from ultra-processed products. Younger age and greater waist circumference are associated with MSM consumption. Younger age and lesser educational level are associated with increased contribution of MSM to total daily kcal intake. MSM consumers have greater consumption of energy, fats, carbohydrates and sodium. Their dietary patterns are characterized by lower consumption of in natura and minimally processed foods, such as tubers and roots, fruits, white and red meat, and eggs and greater consumption of ultra-processed foods and beverages.

Assuntos

Carne , Humanos , Brasil/epidemiologia , Masculino , Adulto , Feminino , Estudos Transversais , Pessoa de Meia-Idade , Ingestão de Energia , Estudos Prospectivos , Preferências Alimentares , Comportamento Alimentar , Comportamento do Consumidor/estatística & dados numéricos , Dieta

RESUMO

Rare earth elements (REEs) have been intentionally used in Chinese agriculture since the 1980s to improve crop yields. Around the world, REEs are also involuntarily applied to soils through phosphate fertilizers. These elements are known to alleviate damage in plants under abiotic stresses, yet there is no information on how these elements act in the physiology of plants. The REE mode of action falls within the scope of the hormesis effect, with low-dose stimulation and high-dose adverse reactions. This study aimed to verify how REEs affect rice plants' physiology to test the threshold dose at which REEs could act as biostimulants in these plants. In experiment 1, 0.411 kg ha-1 (foliar application) of a mixture of REE (containing 41.38% Ce, 23.95% La, 13.58% Pr, and 4.32% Nd) was applied, as well as two products containing 41.38% Ce and 23.95% La separately. The characteristics of chlorophyll a fluorescence, gas exchanges, SPAD index, and biomass (pot conditions) were evaluated. For experiment 2, increasing rates of the REE mix (0, 0.1, 0.225, 0.5, and 1 kg ha-1) (field conditions) were used to study their effect on rice grain yield and nutrient concentration of rice leaves. Adding REEs to plants increased biomass production (23% with Ce, 31% with La, and 63% with REE Mix application) due to improved photosynthetic rate (8% with Ce, 15% with La, and 27% with REE mix), favored by the higher electronic flow (photosynthetic electron transport chain) (increase of 17%) and by the higher Fv/Fm (increase of 14%) and quantum yield of photosystem II (increase of 20% with Ce and La, and 29% with REE Mix), as well as by increased stomatal conductance (increase of 36%) and SPAD index (increase of 10% with Ce, 12% with La, and 15% with REE mix). Moreover, adding REEs potentiated the photosynthetic process by increasing rice leaves' N, Mg, K, and Mn concentrations (24-46%). The dose for the higher rice grain yield (an increase of 113%) was estimated for the REE mix at 0.72 kg ha-1.