The integration of organic and inorganic fertilizers is gaining importance as a strategy to improve crop yield while maintaining soil health and reducing environmental risks. Poultry manure is a nutrient-rich organic amendment that can enhance soil fertility and partially replace synthetic nitrogen (N) fertilizers. This study aimed to evaluate the effects of poultry manure applied at six rates (0, 250, 500, 750, 1000, and 2000 kg/da) in combination with a fixed dose of chemical N fertilizer (20 kg N/da) on wheat (Triticum aestivum L.) yield, plant nutrient composition (N, P, K, Ca, Mg), soil nutrient availability, and soil electrical conductivity (EC) under greenhouse conditions. The experiment was conducted in 5 kg pots filled with clay loam soil (pH 7.6; CaCO₃ 9.6%; OM 1.35%). All pots received uniform basal applications of P and K (20 kg/da each). After 90 days, plants and soils were analyzed for nutrient contents. Results showed that grain yield significantly increased with manure application, reaching a peak of 5.74 kg/pot at 1000 kg/da. Grain N, K, and Ca contents increased significantly, while P and Mg showed minor or statistically non-significant trends. Soil nutrient levels also improved across all manure doses, particularly for N, K, and Ca. However, soil EC increased steadily from 1.39 to 3.12 dS/m with increasing manure dose, indicating a risk of salinity buildup at high application rates. The results suggest that poultry manure, when applied at moderate doses, can effectively improve wheat yield and nutrient availability while reducing the need for synthetic N fertilizers. However, EC monitoring is essential to avoid salinity-related constraints, especially in greenhouse or poorly drained conditions.

This study investigated the effects of foliar-applied humic acid-based fertilizers on potato (Solanum tuberosum L.) yield, tuber quality, and nutrient uptake efficiency under irrigated conditions in Western Kazakhstan. A three-year field experiment (2021–2023) was conducted using the Silvana potato variety, a medium-early cultivar with high yield potential. The randomized complete block design included five treatments: (1) Control (no fertilizers), (2) Reasil Micro Hydro Mix, (3) Reasil Micro Hydro Mix + Reasil Forte Carb-Nitrogen-Humic, (4) Potassium Humate, and (5) Potassium Humate + Reasil Forte Carb-Nitrogen-Humic. All fertilizers were applied as foliar sprays at three critical growth stages: stem formation, bud appearance, and tuber formation. The humic acid-based fertilizers used in the study were produced by LLC "Life Force Group". Potassium Humate is an 80% alkaline extract of humic and fulvic acids from leonardite. Reasil Micro Hydro Mix contains various essential micronutrients, including N, Mg, B, Fe, Zn, and amino acids. Reasil Forte Carb-Nitrogen-Humic is rich in N (20%, including 18% amide-N) and also contains humic acids (6.2%), hydroxycarboxylic acids (6.2%), and amino acids (6%). Results showed that foliar humic acid application significantly increased potato yield and improved tuber quality. The highest average marketable yield (28.79 t/ha) was obtained with Potassium Humate + Reasil Forte Carb-Nitrogen-Humic, reflecting a 20% increase over the control. Starch content was also highest in this treatment (16.9%), while vitamin C content was better maintained in treated plots under stress conditions. Additionally, nitrate accumulation in tubers was reduced, improving food safety. Nutrient uptake efficiency was significantly enhanced by humic acid-based foliar treatments. The Potassium Humate + Reasil Forte Carb-Nitrogen-Humic treatment recorded the highest N, P, and K absorption levels, confirming the role of foliar humic applications in optimizing nutrient translocation. These findings demonstrate that humic acid-based foliar fertilization is an effective strategy for increasing potato productivity while reducing reliance on conventional fertilizers. These findings highlight the potential of foliar-applied humic substances as a sustainable alternative to conventional fertilization, particularly in semi-arid agricultural systems.

Repeated sowing of winter cereals represents one of the adaptive dryland approaches to make more sustainable the rainfed agriculture activities in southern Kazakhstan. This study conducted a multi-year reconstruction of crop transitions using Sentinel-2 imagery for 2018–2025, based on the combined analysis of Normalized Difference Vegetation Index (NDVI) temporal profiles and the Plowed Land Index (PLI), enabling the creation of a field-level harmonized classification set. The transition “spring crop → winter crop” was used as a formal indicator of repeated winter sowing, from which annual repeat layers and an integrated metric, the R-index, were derived. The results revealed a pronounced spatial concentration of repeated sowing in foothill landscapes, where terrain heterogeneity and locally elevated moisture availability promote the recurrent return of winter cereals. Comparison of NDVI composites for the peak spring biomass period (1–20 May) showed a systematic decline in NDVI with increasing R-index, indicating the cumulative effect of repeated soil exploitation and the sensitivity of winter crops to climatic constraints. Precipitation analysis for 2017–2024 confirmed the strong influence of autumn moisture conditions on repetition phases, particularly in years with extreme rainfall anomalies. These findings demonstrate the importance of integrating multi-year satellite observations with climatic indicators for monitoring the resilience of agricultural systems. The identified patterns highlight the necessity of implementing nature-based solutions, including contour–strip land management and the development of protective shelterbelts, to enhance soil moisture retention and improve the stability of regional agricultural landscapes.

Global food security is increasingly threatened by escalating water scarcity and progressive soil degradation, particularly subsoil compaction resulting from repeated heavy machinery traffic. In many arid and semi-arid regions, bulk soil density may reach 1.68 g cm⁻³ in the 40–60 cm layer of heavy clay–loam soils, severely restricting water infiltration, gaseous exchange, and nutrient transport, ultimately causing substantial yield losses. This study investigated the synergistic effects of deep slitting (subsoiling) and superabsorbent hydrogel polymer (SAP) application on soil moisture dynamics and the productivity of Baisheshek barley (Hordeum vulgare L.) under the arid steppe conditions of the Turkestan Region, Kazakhstan. A field experiment with four replications and seven treatments was conducted on compacted heavy clay–loam soil. Soil sampling and agrochemical analyses were performed across three representative sites to account for spatial heterogeneity and to evaluate the robustness of the proposed technology under variable field conditions. Treatments combined two slitting depths (20 cm and 40 cm) with two hydrogel rates (30 kg ha⁻¹ and 60 kg ha⁻¹). The optimal treatment—20 cm slitting with 30 kg ha⁻¹ hydrogel (SCH-20+30)—produced the most favorable soil moisture retention and highest agronomic performance, achieving a yield of 23.2 c ha⁻¹, a 53.6% increase (8.1 c ha⁻¹ gain) over the control (15.1 c ha⁻¹). The 30 kg ha⁻¹ dose was also the most economically efficient, as doubling the rate provided no significant benefit. To enable practical implementation, a patented Combined Seeding Unit (CSU) was developed to integrate deep slitting, hydrogel application, fertilizer placement, and seeding into a single-pass operation. This innovative methodology represents a technologically advanced, water-efficient, and sustainable approach for high-yield barley and other grain cultivation in arid and semi-arid regions, offering a practical model for precision soil and water management under climate-induced water scarcity.

Tomato (Solanum lycopersicum L.) is a widely cultivated vegetable crop in Kazakhstan, yet its productivity and quality are often limited by soil degradation, nutrient imbalances, and the excessive use of mineral fertilizers. Natural zeolites, particularly clinoptilolite, offer potential as soil amendments due to their high cation exchange capacity, water retention properties, and ability to regulate nutrient availability. This study aimed to evaluate the effects of natural zeolite (2 t/ha), alone and in combination with two mineral fertilizer doses (N₄₅P₄₅K₄₅ and N₉₀P₉₀K₉₀), on tomato yield, fruit quality, soil heavy metal content, and economic profitability under dark chestnut soil conditions in southeastern Kazakhstan. A field experiment was conducted using a randomized complete block design with six treatments and three replications. Results showed that all treatments increased yield compared to the control (21.7 t/ha), with the highest yield (29.1 t/ha) observed under the zeolite + N₉₀P₉₀K₉₀ treatment. Fruit quality improved in terms of dry matter (up to 5.46%) and sugar content (up to 3.80%) with zeolite and fertilizer combinations. Nitrate accumulation in fruits was highest under N₉₀P₉₀K₉₀ alone (78 mg/kg) but decreased significantly when combined with zeolite (64 mg/kg), indicating the mineral’s capacity to reduce nitrate uptake. Heavy metal analysis revealed that zeolite reduced the bioavailability of cadmium and lead in soil, keeping concentrations below permissible limits. Economic evaluation indicated that the zeolite-only treatment provided the highest profitability (171%) due to relatively low input costs and moderate yield gains. Overall, the results demonstrate that zeolite, especially when integrated with moderate fertilizer inputs, enhances tomato productivity, improves fruit safety, and supports sustainable soil management. Its use can be particularly beneficial in resource-limited and environmentally sensitive agricultural systems.

Nitrogen (N) is a crucial nutrient for potato (Solanum tuberosum L.) production, but excessive application can lead to environmental degradation and reduced nitrogen use efficiency (NUE). This study evaluated the effects of different nitrogen application rates (0, 60, 120, 150, 180, 210, and 240 kg N/ha) on tuber yield, nitrogen uptake, and soil nitrate accumulation over two growing seasons. The results showed that the highest tuber yield (20.8 t/ha) was obtained at 150 kg N/ha, beyond which further increases in nitrogen application did not result in significant yield improvements (P