Agave lechuguilla Torr., of the family Agavaceae, is distributed from southwestern United States to southern Mexico and is one of the most representative species of arid and semiarid regions. Its fiber is extracted for multiple purposes. The objective of this study was to generate a robust model to predict dry fiber yield (Dfw) rapidly, simply, and inexpensively. We used a power model in its linear form and bioclimatic areas as dummy variables. Training, generation (80%) and validation (20%) of the model was performed using machine learning with the package ‘caret’ of R. Using canonical correlation analysis (CCA), we evaluated the relationship of Dwf to bioclimatic variables. The principal components analysis (PCA) generated two bioclimatic zones, each with different A. lechuguilla productivities. We evaluated 499 individuals in four states of Mexico. The crown diameter (Cd) of this species adequately predicts its fiber dry weight (R² = 0.6327; p < 0.05). The intercept (β₀), slope [lnCd (β₁)], zone [(β₂)] and interaction [lnCd:Zona (β₃)] of the dummy model was statistically significant (p < 0.05), giving origin to an equation for each bioclimatic zone. The CCA indicates a positive correlation between minimum temperature of the coldest month (Bio 6) and Dwf (r = 0.84 and p < 0.05). In conclusion, because of the decrease in Bio 6 of more than 0.5°C by 2050, the species could be vulnerable to climate change, and A. lechuguilla fiber production could be affected gradually in the coming years.

In many regions, conservation tillage has been shown to contribute to preserving soil properties. However, in order to promote this practice in new areas, it is necessary to generate information about its results in local environmental conditions. Our objective was to study the effect of No Tillage (NT), Vertical Tillage (VT) and Conventional Tillage (CT) on physical soil properties of a clay loam soil and on yields (Avena sativa L.), in a semiarid area of Mexico. From 2013 to 2016 an experiment was conducted in random blocks, with the three tillage systems as treatments. Four variables were measured; bulk density (Bd), pore space (P), hydraulic conductivity (Ks) and crop yield. Our results did show scarce differences between the tillage systems. Values ranged between 1.21 g cm⁻³ to 1.39 g cm⁻³ for Bd, 45% to 55% for P, and 4.29 mm h⁻¹ to 13.61 mm h⁻¹ for Ks. Although differences were not significant among treatments, Bd decreased 6.7% for CT, 5.6% for NT and 0.7% for VT. P increased 6% for CT, 5% for NT and 0.5% for VT. Ks for CT decreased 6% more than for NT and VT. Average yield was 13% less in NT compared to CT and VT. A long-term investigation is needed in order to determine the effects of tillage methods, in our particular environmental conditions.

Background: Adult pecan trees require a significant water supply for high yields and nut quality. Pecan nut orchards are established in semi-arid regions where water is the primary limiting resource for agriculture. Therefore, in these regions, improving water use efficiency is essential. Objective: Evaluate the water use efficiency of a pecan tree orchard based on the comparison of irrigation scheduling with the evapotranspiration rate data. Methods: The study was conducted in a pecan nut (Carya illinoinensis) orchard of 7.2 ha with 7-year-old Western and Wichita cv tress. The volume of water applied to each tree (drip irrigation) was converted to a daily irrigation depth and compared against the daily rate of actual (measured with an Eddy covariance system) and the FAO Penman-Monteith evapotranspiration. Results: Comparing the monthly water depth applied to each tree against the monthly FAO-Penman Monteith ET, surplus or deficit irrigation episodes were detected. Because the canopy trees only covered 18.7% of the orchard area, the daily rate of actual evapotranspiration during the months of the trees growing was very small (1 to 2 mm) compared with the orchards of mature pecan trees. The corresponding monthly crop coefficients (Kc) were also small (0.315 on average). Conclusion: This study showed that by comparing the rate of ETref against the irrigation depth applied to the trees in the irrigation scheduling, it is possible to reveal cases of surplus or deficit of water supplied to a pecan nut orchard.

Arsenic contamination demands innovative, sustainable remediation. This study presents a fuzzy approach for synthesizing a magnetic biochar nanocomposite from pecan shell agricultural waste for efficient arsenic removal. Using a Multi-Input Fuzzy Rules Emulated Network (MiFREN), a systematic investigation of the synthesis process revealed that precursor type (biochar), Fe:precursor ratio (1:1), and iron salt type were the most significant parameters governing material crystallinity and adsorption performance, while particle size and N₂ atmosphere had a minimal effect. The MiFREN-identified optimal material, the magnetic biochar composite (FS7), achieved > 90% arsenic removal, outperforming the least efficient sample by 50.61%. Kinetic analysis confirmed chemisorption on a heterogeneous surface (q_e = 12.74 mg/g). Regeneration studies using 0.1 M NaOH demonstrated high stability, with FS7 retaining > 70% removal capacity over six cycles. Desorption occurs via ion exchange and electrostatic repulsion, with post-use analysis confirming structural integrity and resistance to oxidation. Application to real groundwater from the La Laguna region proved highly effective; FS7 maintained selectivity despite competing ions like ${Na}^{+}$, ${Cl}^{-},$ and ${SO}_4^{2-}$. By integrating AI-driven optimization with reusability and real contaminated water, this research establishes a scalable framework for transforming agricultural waste into a high-performance adsorbent, supporting global Clean Water and Sanitation goals.

Arsenic contamination in water demands effective, low-cost removal methods. This study introduces nanomagnetite-coated biochar derived from pecan nutshells for efficient arsenic adsorption. Utilizing a solvothermal method, uniform magnetite crystals were grown on biochar in a controlled process at 200 °C. The resulting bioadsorbent, characterized by XRD, SEM, and FTIR, exhibited a narrow size distribution and consistently high arsenic removal rates (97.30–98.76%). Biochar with varied particle sizes, synthesized at a short reaction time (6 h), showed the highest removal efficiency of arsenic (98.76%) and adsorption capacity (7.974 mg/g). This approach offers a sustainable for arsenic remediation, and ease of magnetic separation.

Background: Deficit irrigation is an approach to use less water in crop growth in places where water resources are the limiting factor for agricultural production, to maximize the production per unit of volume of water available. Objective: The study aimed to evaluate the effect of four levels of irrigation applied to replenish soil moisture depletion on the growth and yield of two sweet pepper cultivars. Methods: The experiment was performed on field conditions from January to June 2020 in a randomized block experimental design with three repetitions arranged in divided plots, the main plot was the four irrigation depths, and the sub-plots were the two cultivars (Tres Filos and Pepón) for a total of eight treatments. The irrigation depths applied corresponded to 60%, 80%, 100%, and 120% of the crop evapotranspiration. Results: The ANOVA (analysis of variance) of the main factors indicates that for the irrigation treatment factor, the number of fruits per plant for the two varieties is statistically equal when irrigation is applied at 120, 100 and 80% of the crop evapotranspiration (ETc) and greater than the one obtained with irrigation at 60% of ETc. For the cultivars factor, the number of fruits per plant and the fruit yield (g plant^-1) in the different irrigation treatments was higher in the cv Tres Filo, but the weight of the fruit was higher in the cv Pepón. Conclusion: The application of irrigation at 60% of the ETc represents a saving of 40% of the volume of water compared to the application at 100% of ETc. The reduction in the number of fruits per plant, fruit weight, and average yield (g plant^-1) of both cultivars was only 4.21%, 7.47%, and 11.95%, respectively. Therefore, if the limiting factor for agricultural production is water availability, it is advisable to irrigate at 60% of the ETc and increase the surface for irrigation to increase total production.