Fungal biosorption is an environmental biotechnology based on the ability of the fungal cell wall to concentrate harmful water pollutants. Among its advantages are its simplicity, high efficiency, flexibility of operation, and low cost. The biosorptive performance of fungal pellets is getting growing attention since they offer process advantages over the culture of disperse mycelia, such as an enhanced biomass separation, and a high resilience in severe environmental conditions. In this review, biosorption capacity of fungal pellets towards heavy metals, dyes, phenolic compounds, humic substances, pesticides, and pharmaceuticals was reviewed. Available data about the adsorption capacity of pellets, their removal efficiency, and the operational conditions used were collected and synthesized. The studies relying on biodegradation were discarded to present only the possibilities of fungal pellets for removing these concern pollutants through biosorption. It was found that the biosorption of complex mixtures of pollutants on fungal pellets is scarcely studied, as well as the interfering effect of anions commonly found in water and wastewater. Furthermore, there is a lack of research with real wastewater and at pilot and large scale. These topics need to be further explored to take full advantage of fungal pellets on improving the quality of aquatic systems.

Nitrogen (N) fertilizers are one of the most expensive inputs in agricultural settings. Additionally, the loss of N increases costs, contributes to soil acidification, and causes off-site pollution of the air, groundwater and waterways. This study reviews current knowledge about technologies for N fertilization with potential to increase N use efficiency and reduce its negative effects on the environment. Classic inorganic sources such as urea and ammonium sulfate are the major sources utilized, while controlled N release fertilizers have not been significantly adopted for cereals and oil crops. Microorganisms, with the exception of Rhizobium sp. in soybeans, are also not widely used nowadays (e.g., plant growth-promoting bacteria and cynobacteria). The interest in implementing new N fertilization knowledge is stimulating the development of sensors to diagnose the N status and decision support systems for integrating several variables to optimize sources, rates and methods of application. Among potential new technologies we identified the incipient development of nanofertilizers, nutrient formulations to coat seeds, and recycled nutrients. Furthermore, increasing concern about the environmental consequences of N may facilitate the implementation of innovations outside the farm such as more effective regulations to guide N fertilization and methods to manufacture N fertilizers that are more energy-efficient and less CO₂ equivalent emitting.

Alkaline soils with low buffering capacity are susceptible to amendments such as biochar or biofertilizers, which could drastically alter their pH. For that, this study aimed to evaluate the effectiveness of a low biochar and biofertilizer addition to improve soil characteristics and the use of nutrients to reduce the doses of chemical fertilizer. For that, we measured the initial effect of biochar addition on the soil characteristics. Then, to evaluate the changes produced by biochar and biofertilizer on cultivated soil, we carried out a greenhouse experiment with Physalis ixocarpa for two crop cycles. We also studied the nutrient use efficiency, comparing chemical fertilization at 100% (without biochar) against 50% and 20% with biochar on crop yield, plant height, fruit weight, and root length. Finally, we compared the combination of biochar and biofertilizer with the treatments mentioned earlier. The results showed that after adding 0.2% of bamboo biochar, bulk density (BD) decreased while CEC, as well as OM, P_av, Fe, and Cu contents, increased in the soil. The combination of biochar and biofertilizer improved WHC, P_av, and OM comparing to the soil added with biochar. We found that the bamboo biochar and nopal-based fertilizer are suitable improvers for the studied soil.

This paper deals with the design of a bioretention cell and an infiltration trench in a semi- arid micro watershed. The study area was analyzed by characteristics such as slope changes (S), direction and maximum length of the urban runoff (L), and soil use (runoff coefficient, R_c). The bioretention cell was designed by the calculation of variables such as drainage area (A), concentration time (T_c), rainfall intensity (i), maximum peak drained (Q_max), inlet and outlet runoff (Q_a and Q_out, respectively), temperature (T), evaporation (Ev), potential evapotranspiration (PE_m), consumptive use (U) for tolerant plants to semi-arid climates, and soil infiltration capacity (Inf). To design the infiltration trench, only T_c, Q_max, and i were taken into account. The results showed that the designed bioretention cell could retain between 5.37% and 2.25% of runoff volume. As the efficiency of the bioretention cell can be defined by the need for additional irrigation, our results showed that the cell is inefficient in some of the dry months (November and December), even in years characterized by abundant rainfall. Besides, it was shown that the designed infiltration trench could store or infiltrate the water from typical rain events. Based on these results, it is the implementation of more Low-Impact Development (LID) for runoff management in the study area is recommended.