Protecting humankind’s natural resources and soils, including forestry, represents a top priority in agriculture. Addressing climate change should prioritize preserving and enhancing organic carbon, specifically humus, in soils. In this paper, we examine the impact of soil preparation on soil humus and microbial life during the reforestation of Southern Nyírség, Hungary. We determined soil plasticity, pH in distilled water solution, the quantity and quality of humus content, the total number of bacteria and microbial fungi, as well as CO₂ production. In addition to stump removal and plowing, the wealthiest layer of organic matter was detached from the surface. A significant decrease in humus content (HU%) was observed at the five experimental sites (loss of 19.20–40.14 HU% at 0–30 cm depth). Soil organic matter is concentrated in the stump depositions. According to the results, the quantity of humus content is strongly correlated with the measured parameters of soil life, specifically with the number of microbial fungi (r = 0.806 **) and the total number of bacteria (r = 0.648 **). Another correlation (r = 0.607 **) was assessed between the humus content and CO₂ production. This study helps to understand the importance of the no-tillage methods used in reforestation.

In this study, we investigate the nutrient supply of young corn (Zea mays var. rugosa) plants using conventional biological and chemical methods, as well as the N-glycan and metabolic profile of the plant sap using the MALDI-MS. Corn plants with three different nutrient supplies were grown on sandy soil for 45 days after emergence. In treatment 1 (T1), used as a control, the plants did not receive any nutrient supplementation. Plants in treatment 2 (T2) received “ideal” N-, P-, and K-nutrient supplementation in the form of inorganic fertilizers. In treatment 3 (T3), the plants were provided with the ideal amount of P and K, and a reduced amount of N fertilizer. In addition to the amount of biomass of the young plants, macronutrient content (N, P, K, Ca, and Mg) was measured in the dry matter. We examined the amount of 0.01 M CaCl₂-soluble N fractions of the experimental soils, and the P, K, Ca, and Mg content of their ammonium lactate (AL)-soluble fractions. We were unable to statistically distinguish between T1, T2, and T3 treatments using conventional methods (in this phenophase). Metabolic profiles in the sap from young plants, captured by MALDI-MS, showed significant differences between the control, “ideal”, and N-deficient treatments. This method may also be suitable for early detection of N-deficient conditions in other plants.

Black locust (Robinia pseudoacacia L.) has exceptional growth capacity in nutrient-poor environments and is therefore widely used for afforestation and land reclamation on degraded soils. However, drought stress can restrict sapling growth, which undermines the success of their establishment. The effect of a product containing two endophytic strains (Trichoderma afroharzianum P. Chaverri, F.B. Rocha, Degenkolb & Druzhinina TR04 and Trichoderma simmonsii P. Chaverri, F.B. Rocha, Degenkolb & Druzhinina TR05) was studied on a black locust sapling stand under severe drought in eastern Hungary. The two-year-old saplings were root-soaked before planting in sandy soil. The growth of Trichoderma-treated plants improved by late spring. Compared to the control trees, average height increased by 25.75%, and root collar diameter was 21.96% larger. Treated plants also showed 9.1% higher chlorophyll content and 11.1% Normalized Difference Vegetation Index (NDVI). The reduced intercellular CO₂ concentration, together with slightly lower stomatal conductance and increased transpiration rate, suggests tighter stomatal regulation and altered water-use dynamics under drought conditions. These responses indicate improved short-term drought acclimation rather than enhanced carbon assimilation capacity. Pre-planting inoculation with endophytic Trichoderma strains provides a sustainable method to enhance the early establishment and drought resilience of black locust, thereby increasing the efficacy of forest restoration by improving the survival of black locust on challenging degraded sites.

Phosphogypsum (PG) is a high-volume industrial by-product that is receiving increasing attention as an alternative soil amendment. This study presents a two-year pot experiment evaluating the effects of PG on spring wheat (Triticum aestivum L.) grown on two contrasting soils: an acidic, sulfur-deficient Arenosol and a sodium-affected Solonetz. Treatments comprised an untreated control and PG applications at 2 and 10 t ha⁻¹, applied once in year 1 and repeated at the same rates in year 2. In the Solonetz, PG increased grain yield by 48–73% in year 2 and 31–40% in year 1, with the lower dose (2 t ha⁻¹) providing sufficient agronomic benefits. In contrast, no yield response was observed in the Arenosol. In both soils, PG acted as a slow-release sulfur source, increasing straw sulfur concentrations in the second year. Even the repeated application of the highest PG dose (10 t ha⁻¹) did not increase Al, Cd, Cr, or Sr accumulation in wheat grain, indicating no treatment-related increase in trace-element accumulation. PG also increased soil microbial biomass and altered the microbial community structure in the Solonetz, including higher relative abundances of arbuscular mycorrhizal fungi and actinomycetes. Overall, these results demonstrate the dual agronomic function of PG in improving sodic soil productivity and supplying sulfur to nutrient-deficient sandy soils without increasing treatment-related trace-element accumulation, thus highlighting its potential as a soil amendment in sustainable nutrient management systems.