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Driving wheel slippage in agricultural tractors is influenced by soil moisture, density, and penetration resistance. These surface variations reflect post-tillage composition, enabling dynamic mapping via Remotely Piloted Aircraft (RPAs). This study evaluated ballast recommendations based on soil surface data and slippage percentages, correlating added wheel weights at different speeds for a tractor-reversible plow system. Six 94.5 m2 quadrants were analyzed for slippage monitored by RPA (Mavic3M-RTK) pre- and post-agricultural operation overflights and soil sampling (moisture, density, penetration resistance). A 2 × 2 factorial scheme (F-test) assessed soil-surface attribute correlations and slippage under varying ballasts (52.5–57.5 kg/hp) and speeds. Results showed slippage ranged from 4.06% (52.5 kg/hp, fourth reduced gear) to 11.32% (57.5 kg/hp, same gear), with liquid ballast and gear selection significantly impacting performance in friable clayey soil. Digital Elevation Model (DEM) and spectral indices derived from RPA imagery, including Normalized Difference Red Edge (NDRE), Normalized Difference Water Index (NDWI), Bare Soil Index (BSI), Green–Red Vegetation Index (GRVI), Visible Atmospherically Resistant Index (VARI), and Slope, proved effective. The approach reduced tractor slippage from 11.32% (heavy ballast, 4th gear) to 4.06% (moderate ballast, 4th gear), showing clear improvement in traction performance. The integration of indices and slope metrics supported ballast adjustment strategies, particularly for secondary plowing operations, contributing to improved traction performance and overall operational efficiency.

ABSTRACT Soil is the habitat for a number of living organisms that perform essential functions within the ecosystem; their functions and interactions are modified according to different ways of land occupation. Thus, the objective of this study was to evaluate the diversity of edaphic fauna in different soil occupation systems. The study was carried out in different soil occupation systems: millet, maize, soybean, eucalyptus, preserved cerrado, disturbed cerrado, and pasture, with 130 pitfall traps installed per treatment. Soil fauna organisms were identified at the level of large groups (orders and family), and then examined under the following biological diversity indices: Shannon index, Pielou index, average and total richness, and abundance. The highest abundance was found under millet growing conditions (9,974 individuals), and the lowest abundance values were found in soybean soil (222 individuals) and maize (824 individuals). Uniform distribution of groups in the area with soybean crops, due to the homogeneous management of the area, provided the highest biological index (H'=2.69). Principal component analysis (PCA) explained 50.9% of the data along the main axis and 34.6% of the data along the secondary axis. The different systems of soil occupation showed different abundance and diversity, demonstrating how soil occupation interferes with the dynamics of the invertebrate soil fauna. RESUMO O solo é o habitat de vários organismos que desempenham funções essenciais para o ecossistema, cujo conjunto de funções e interações são modificadas pelas diferentes maneiras de ocupação do solo. Assim, o objetivo deste trabalho é avaliar a diversidade da fauna edáfica em diferentes sistemas de ocupação do solo. O estudo foi desenvolvido em diferentes sistemas de ocupação do solo: milheto, milho, soja, eucalipto, cerrado preservado, cerrado antropizado e pastagem, onde foram instaladas 130 armadilhas do tipo pitfall por tratamento. Os organismos da fauna do solo foram identificados a nível de grandes grupos (ordens e família), e, depois, os índices de diversidade biológica: índice de Shannon, índice de Pielou, riqueza e abundância média e total. A maior abundância foi encontrada para milheto (9.974 indivíduos), e os menores valores de abundância foram verificados para soja (222 indivíduos) e milho (824 indivíduos), respectivamente. A distribuição uniforme dos grupos na área de soja, devido ao manejo homogêneo da área, proporcionou o maior índice biológico (H’=2,69). A análise de componentes principais (PCA) explicou no eixo principal 50,9% dos dados e no eixo secundário 34,6% dos dados. Os diferentes sistemas de ocupação do solo, apresentaram abundância e diversidade distinta, demonstrando como a ocupação do solo interfere sobre a dinâmica da fauna invertebrada do solo.

Water scarcity in semiarid regions represents a critical challenge for sustainable agriculture, reducing the availability of forage and affecting livestock systems. The reuse of treated wastewater offers an environmentally friendly alternative to meet water and nutrient needs, supporting the principles of the circular economy. Sweet sorghum, with its remarkable tolerance to abiotic stress, represents a resilient crop option. Evaluating its agronomic and industrial responses to different depths of irrigation using reclaimed water is essential for improving resource-efficient agricultural practices in water-limited environments. This study evaluated the effects of different irrigation regimes with treated wastewater on the growth, productivity, and water use efficiency of sweet sorghum grown in a semiarid region of Brazil. The experiment was conducted in a randomized complete block design, with five irrigation regimes ranging from 50% to 150% of crop evapotranspiration (ETc) and four replications. Irrigation was carried out with treated wastewater using a drip irrigation system. Growth parameters, fresh biomass, water use efficiency, and soluble solids content (°Brix) were analyzed in two consecutive harvests (main and ratoon crop). Deficit irrigation regimes (50% and 75% of ETc) resulted in higher water use efficiency and higher °Brix, whereas regimes above 100% of ETc reduced water use efficiency and biomass productivity. The ratoon crop showed greater sensitivity to water management, with significant productivity responses under irrigation around 100% of ETc. The first harvest was more productive in terms of fresh biomass and plant growth. Reclaimed water is a sustainable and efficient strategy for cultivating sweet sorghum in semiarid regions. Deficit irrigation regimes can be technically viable for maximizing water use efficiency and production quality, while proper irrigation management is crucial to avoiding losses associated with excessive water application.

High levels of dissolved salts in irrigation water sources limit melon cultivation in northeastern Brazil. In this context, nitrogen fertilization has been employed as one strategy to alleviate the effects of salt stress on plants. This study aimed to evaluate the effect of different nitrogen sources on cantaloupe melon cultivation under fertigation and irrigation with water of the same salinity and different cationic concentrations (Na+ and Ca+). The research consisted of two experiments, each following a randomized complete block design in a 4 × 2 factorial arrangement with four replicates. The treatments included four levels of electrical conductivity of the nutrient solution (2.0; 3.0; 4.0; and 5.0 dS m−1) and two nitrogen sources of different origins: NO3− [Ca(NO3) and KNO3] and NH4+ [CH4N2O and NH4H2PO4]. The following factors were chlorophyll pigments, chlorophyll a fluorescence, and fruit weight. Nitrogen fertilization with NH4+ mitigated salt stress by increasing the synthesis of chlorophyll a and carotenoids in plants irrigated with NaCl-based saline water. Furthermore, there was no influence of nitrogen sources on chlorophyll a fluorescence. Finally, NO3− fertilization reduced the effects of salt stress on the leaf mass ratio, specific leaf area under Ca2+ fertigation, and relative growth rate of leaf area in melons under cationic prevalences of Na+ or Ca2+ (associated with Cl−).

The application of machine learning techniques to determine bioparameters, such as the leaf area index (LAI) and chlorophyll content, has shown significant potential, particularly with the use of unmanned aerial vehicles (UAVs). This study evaluated the use of RGB images obtained from UAVs to estimate bioparameters in sesame crops, utilizing machine learning techniques and data selection methods. The experiment was conducted at the Federal Rural University of Pernambuco and involved using a portable AccuPAR ceptometer to measure the LAI and spectrophotometry to determine photosynthetic pigments. Field images were captured using a DJI Mavic 2 Enterprise Dual remotely piloted aircraft equipped with RGB and thermal cameras. To manage the high dimensionality of the data, CRITIC and Pearson correlation methods were applied to select the most relevant indices for the XGBoost model. The data were divided into training, testing, and validation sets to ensure model generalization, with performance assessed using the R2, MAE, and RMSE metrics. XGBoost effectively estimated the LAI, chlorophyll a, total chlorophyll, and carotenoids (R2 > 0.7) but had limited performance for chlorophyll b. Pearson correlation was found to be the most effective data selection method for the algorithm.

ABSTRACT The production of vegetables in communities of family farmers in semiarid regions is limited due to rudimentary cultivation practices and systems, water scarcity, and excess salts in the water and soil. Thus, the objective of this work was to evaluate the production of rocket (Eruca sativa L. cv. Folha Larga) in a low cost hydroponic system, considering strategies for the use of brackish water in the nutrient solution. The experiments were conducted in complete randomized designs, in 6×2 factorial arrangements, with five replications, using rocket plants grown in different nutrient solutions, consisting of six salinity levels (1.5, 3.0, 4.5, 6.0, 7.5, and 9.0 dS m -1) and two circulation frequencies of the nutrient solution (twice a day, at 8:00h, and 16:00h; and three times a day, at 8:00h, 12:00h, and 16:00h). In Experiment I, the nutrient solution lost by evapotranspiration was replenished with the respective brackish water used in its preparation; and in Experiment II it was replenished with public water (0.12 dS m -1). The shoot and root fresh and dry biomass of the plants and their respective dry weight proportions, and biometric variables were evaluated. Replenishing of the nutrient solution with public water resulted in lower losses in biomass and plant growth. The increases in circulation frequency of the nutrient solution did not affect the biometric variables, however, the plants prioritized shoot biomass development to the detriment of the root when using high circulation frequencies. RESUMO A produção de hortaliças em comunidades de agricultores familiares, residentes em condições semiáridas, são limitadas por práticas e sistemas rudimentares de cultivo, escassez hídrica e problemas de salinidade. Neste sentido, o objetivo do presente trabalho foi analisar a produção de rúcula, cv. Folha larga, em sistema de hidroponia de baixo custo, adotando-se estratégias de uso da água salina no preparo e reposição da solução nutritiva evapotranspirada. Em dois experimentos, plantas de rúcula foram expostas a seis níveis de salinidade da solução nutritiva (1,5; 3,0; 4,5; 6,0; 7,5 e 9,0 dS m -1) aplicadas em duas frequências de circulação (duas vezes ao dia - às 8 e 16 horas; três vezes ao dia - às 8, 12 e 16 horas). O delineamento experimental adotado foi inteiramente casualizado, em esquema fatorial 6 x 2, com cinco repetições, sendo que, no Experimento I a reposição da solução nutritiva foi efetuada com a respectiva água salina utilizada no preparo da solução e, no Experimento II, com água de abastecimento (0,12 dS m -1). Analisou-se a fitomassa fresca e seca da planta, da parte aérea e da raiz, bem como as respectivas partições de matéria seca e variáveis biométricas. A reposição da lâmina evapotranspirada com água de abastecimento resultou em menores perdas de biomassa e no crescimento das plantas e que, o aumento da frequência de circulação não influenciou as variáveis biométricas, no entanto, sob maior frequência de circulação a planta priorizou o desenvolvimento da biomassa da parte aérea em detrimento da raiz.

Vinasse is an organic matter and nutrient-rich residue generated during alcohol distillation. However, if applied to crops in excess, it may disturb the complex balance of soil absoption and contaminate groundwater. The goal of this research was to evaluate the effect of a vinasse-distributing pool on the quality of groundwater in a sugarcane field in Pernambuco State, Brazil. Samples were collected from 10 observation wells along three parallel transects around the vinasse-distributing pool. The quality of groundwater as well as the fluvial water of the Ipojuca River was assessed as a control for ocean intrusion. The following parameters were measured: CE, SDT, pH, COD, BOD, NO super(-) sub(3), NO super(-) sub(2), K super(+), Ca super(2+), Mg super(2+), Na super(+), Cl super(-) and HCO super(-) sub(3). Storing vinasse in the distribution lake disturbed CE, COD and BOD values as well TDS, Cl super(-), K super(+), Ca super(2+) and Mg super(2+) concentrations in groundwater.

Treated domestic sewage (TDS) can contribute to plant nutrition and improve crop production. However, there are no data for its use in coloured cotton under a deficit or excess irrigation in combination with potassium fertilization rates (KRs), mainly under semiarid tropical conditions. The research was conducted using a randomized complete block design in a factorial scheme (5 × 5, irrigation regimes vs. potassium rates), plus an additional treatment as the control ((5 × 5) + 1). The treatments consisted of five TDS irrigation regimes (50, 75, 100, 125, and 150% of crop evapotranspiration—ETC) and five KRs (0, 50, 100, 150, and 200% of the local crop recommendation), plus a control—CT— (irrigated with fresh water at 100% ETC and fertilized according to the local crop recommendation) and four replications. The optimal crop yield, water use efficiency, and potassium use efficiency were obtained when TDS was applied as a deficit irrigation treatment of 75% of ETC or as full irrigation (100% of ETC) and when associated with moderate increases in K fertilization. These treatments also resulted in a better fibre quality when compared to the CT, meeting or exceeding the requirements of the textile industry. Therefore, moderate deficit irrigation with TDS is indicated as an important strategy to save fresh water and to reduce the use of fertilizers, while having the potential to increase profit margins for cotton production in tropical semiarid regions.

Objetivou-se com este trabalho avaliar a concentração dos nutrientes no tecido foliar das plantas de tomate cereja cv. “Rita”, cultivadas em sistema hidropônico utilizando água com crescentes níveis de salinidade no preparo da solução nutritiva, submetendo as plantas a diferentes tempos de exposição à salinidade e turnos de rega. O experimento foi conduzido em casa de vegetação em sistema hidropônico em vasos com substrato. O delineamento experimental foi em blocos inteiramente casualizados em esquema fatorial 6 x 2 x 2, sendo seis níveis de salinidade da solução nutritiva (3,01; 4,51; 5,94; 7,34; 8,71 e 10,40 dS m-1), dois tempos de exposição das plantas à salinidade (51 e 6 dias) e dois turnos de rega (uma irrigação por dia e uma irrigação a cada dois dias). Foram avaliadas as concentrações de nitrogênio, fósforo, potássio, cálcio, magnésio, enxofre, sódio e cloro no tecido foliar das plantas. O uso de água salobra no preparo da solução nutritiva promoveu efeitos de interações antagônicas entre os nutrientes, afetando as concentrações dos mesmos. O aumento da salinidade provocou aumentos nas concentrações de sódio e cloro e redução nas concentrações de potássio e nitrogênio no tecido foliar. O menor tempo de exposição das plantas à salinidade proporcionou reduções de menores magnitudes nas concentrações de potássio e nitrogênio e diminui as concentrações de sódio e cloro. O turno de rega com uma irrigação a cada dois dias afetou as concentrações foliares de nitrogênio, cálcio e magnésio.

ABSTRACT Groundwater with high salt concentrations is common in the semiarid region of Brazil. It often makes them inappropriate to conventional agricultural production of vegetables. Therefore, the objective of this work was to evaluate watercress and Chinese cabbage crops under a nutrient film technique (NFT) hydroponic system using brackish groundwater. The experiment was carried out in the Poço do Boi region, in Ibimirim, Pernambuco, Brazil (8º32'15\"S, 37º41'30\"W, and altitude of 431 m). The treatments used were: public water (T1), calcium sulfate water (T2), magnesium chloride water S1 (T3), calcium chloride water (T4), sodium chloride water (T5), and magnesium chloride water S2 (T6). A completely randomized experimental design was used, with six treatments and four replications, totaling 24 plots for each crop. The fresh and dry shoot weights and rates of relative and absolute growths were analyzed. The different waters used affected negatively the growth and yield of the watercress and Chinese cabbage plants. The calcium chloride water was the most suitable for the watercress production. However, none of the groundwaters used could be recommended for production of Chinese cabbage. The lowest growth rates (5.88% to watercress and 0.75% to Chinese cabbage) of the fresh matter were found with the use of magnesium water. RESUMO Em grande parte do semiárido é comum à presença de águas subterrâneas que apresentam concentrações de sais, tais que, muitas vezes, as tornam inapropriadas à produção agrícola de hortaliças de maneira convencional. Assim, objetivou-se com este trabalho avaliar o comportamento das culturas do agrião e da couve chinesa em hidroponia NFT (Nutrient Film Technique), submetidas à utilização de águas salobras subterrâneas. O experimento foi realizado no município Poço do Boi em Ibimirim-PE (8º32'15\" de latitude Sul, 37º41'30\" de longitude Oeste, e a uma altitude 431 m. Os tratamentos foram designados como: T1 - água de abastecimento; T2 - água sulfatada cálcica; T3 - água cloretada magnesiana S1; T4 - água cloretada cálcica; T5 - água cloretada sódica e T6 - água cloretada magnesiana S2. O delineamento experimental foi inteiramente casualizados, com seis tratamentos e quatro repetições, totalizando 24 parcelas experimentais para cada cultura. Avaliou-se as produções de massa de matéria fresca e seca da parte aérea, taxas de crescimento relativo e absoluto. O uso das diferentes águas influenciou de maneira negativa no crescimento e rendimento da cultura do agrião e da couve chinesa, sendo a água cloretada cálcica a mais indicada para a produção do agrião. Já para a couve chinesa nenhuma das águas utilizadas é aconselhada para produção. As menores taxas de crescimento (5,88 % para o agrião e 0,75 % pra o couve) da massa de matéria fresca foram obtidas com o uso da água cloretada magnesiana S2.