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The study concerned the determination of nitrous oxide (N₂O) emissions under conventional and reduced tillage conditions. In the reduced cultivation, a soil cultivating seed drill was used for simultaneous sowing of seeds and subsurface application of fertilizer. The emission levels of the gas tested were dependent on the year of the study and the method of soil tillage, and were subject to considerable changes during the growing season. The use of reduced soil tillage significantly limited emissions of the analysed gas into the atmosphere. Depending on the year of the study, N₂O emission in the reduced tillage system was from 15% to 40% lower than in the conventional system. Low levels of easily mineralized components in soil could have been the cause of the reduction in N₂O emissions to the atmosphere.

Studies on glomalin-related soil protein (GRSP) have focused on soil aggregation and fungal physiology, whereas it is not known how exogenous GRSP could positively impact on these processes, soil enzyme activity and plant growth. Easily extractable GRSP [EE-GRSP, 0.022 mg protein/mL citrate buffer (20 mmol, pH 7.0)] from a 26-year-old citrus orchard was exogenously applied into 5-month-old potted trifoliate orange (Poncirus trifoliata) for 3 months to evaluate effects on soil water-stable aggregate distribution, relevant soil enzyme activities and plant growth. Depending on the applied concentrations as 1/2, 1/4 or full strength, exogenous EE-GRSP generally significantly increased the distribution of soil water-stable aggregates and mean weight diameter (MWD, an aggregate stability indicator). Values of MWD and plant biomass production curvilinearly positively correlated with exogenous EE-GRSP applications. Exogenous EE-GRSP generally significantly increased the activity of rhizospheric polyphenol oxidase, peroxidase, acid and alkaline phosphatase. Both the 1/2-strength and 1/4-strength, but not the full-strength exogenous EE-GRSP, significantly stimulated plant growth performance. Our results firstly demonstrated the positive contribution of exogenous EE-GRSP to soil aggregation, relevant rhizospheric enzyme activities and/or plant growth, which has important implications for exploring GRSP in enhancing soil structure and/or plant performance.

For the purposes of assessment of long-term changes, two sets of Chernozems soil samples were analysed and compared in parallel: 'old' file samples obtained during the Soil Survey 1960-1970 in the former Czechoslovakia and a 'present' (2013) set of samples from exactly the same sites as the archive samples. The recently collected samples revealed worse qualitative parameters (lower humic acid to fulvic acid (HA/FA) ratios and higher colour quotient Q4/6 values) than the file samples, for all the localities. On the other side, the quantitative soil organic matter (SOM) parameters (oxidizable carbon (C_ox) and all its determined components) showed contrary results. The amount of total SOM at the same sites is higher now than it was about 50 years ago. It can be concluded that the current decline in SOM quality in Chernozems is partly compensated for by higher accumulation of SOM in the soils. All the analysed Chernozem samples were found to have much worse qualitative SOM parameters than the values mentioned for this soil type in the older literature. However, a comparison of the current data and the file data of Chernozem SOM quality can still be considered an open issue and require more complex research.

The four-year trial was conducted in north-western Slavonia (main arable crop producing region in Croatia) to evaluate the effects of different tillage systems on the water content of silty loam soil (Albic Luvisol) and yields of maize (Zea mays L.) and winter wheat (Triticum aestivum L.). The tillage systems compared were: conventional tillage; reduced conventional tillage; conservation tillage I; conservation tillage II (CM); no-tillage (NT). During the study period, there were one dry, two wet and one average season. Soil water content (SWC) was measured at 0-5, 15-20 and 30-35 cm depths on a monthly basis. Tillage systems had significant (P < 0.05) effects on SWC and yields. The highest average SWC in all seasons was measured under the NT system, followed by the CM system. In the second season, the highest yield was measured under the NT system while in all other seasons, it was under the CM system.

The research results have shown that the enzyme pH index (0.49-0.83) confirmed the neutral or alkaline nature of the soils. Neither the changes in the content of available phosphorus nor in the activity of dehydrogenases, catalase, alkaline and acid phosphatase in soil were due to the factors triggering soil salinity; they were a result of the naturally high content of carbon of organic compounds, which was statistically verified with the analysis of correlation between the parameters. There were recorded highly significant values of the coefficients of correlation between the content of available phosphorus in soil and the activity of alkaline (r = 0.96; P < 0.05) and acid phosphatase (r = 0.91; P < 0.05) as well as dehydrogenase (r = 0.90; P < 0.05). To sum up, one can state that Mollic Gleysols in Inowrocław are the soils undergoing seasonal salinity; however, a high content of ions responsible for salinity is balanced with a high content of organic carbon, humus, phosphorus and calcium directly affecting the fertility of the soils analyzed. The activity of the enzymes depended on the natural content of carbon of organic compounds and not on the factors affecting the soil salinity, which points to the potential of such tests for soil environment monitoring.

This study monitors the effect of salt stress induced by a NaCl solution (0 - deionized water, 50, 100, 200, 300 mmol/L) in lettuce (Lactuca sativa L. cv. Orion), New Zealand spinach (Tetragonia tetragonoides (Pall) Kuntze) and common purslane (Portulaca oleracea L. cv. Green Purslane) over the course of 50 days. The diverse reactions of these monitored species to salt stress are well apparent from the results. Lettuce proved as the most sensitive to salt stress, showing a significant reduction of dry weight, where even lower concentrations of salt affected membrane stability through increased electrolyte leakage value and an imbalance in the content of Na⁺ and K⁺, observed in the form of lower ratios of K⁺/Na⁺. In case of T. tetragonoides, lower salt concentrations positively affected growth and this species appears to particularly accumulate sodium. In case of P. oleracea no significant reduction of dry weight took place with the increasing concentration of NaCl and a naturally high content of potassium contributed to maintaining a favourable ratio of K⁺/Na⁺ even at higher salt concentrations, which is one of the prerequisites of salt-stress tolerance.

Root net primary productivity (RNPP) was assessed in the wet submontane meadow in the highland region of the Czech Republic. RNPP was studied from 1992 to 1995 with help of the in-growth core technique. The effect of different intensities of fertilization on root growth was covered. In comparison with unfertilized stands, the application of fertilizers (90 kg N/ha) resulted, mostly significantly, in greater root productivity (297 g/m²/year and 2.08 g/m²/day, on average). This represented an increase by 72% and 71%, respectively. Variability in the fraction of RNPP to total net primary productivity was examined. Results indicate that this fraction varied from 0.18 to 0.25 across the compared treatments and decreased with increasing fertilization. Data show how different roles can grasslands play in accumulation of plant matter due to different levels of fertilization.

In order to clarify the response characteristics of tillering and nitrogen (N) uptake and utilization under micro-nano bubble aeration irrigation and nitrogen fertilizer level, the nitrogen uptake and utilization characteristics, tillering and yield of early rice under different irrigation methods and nitrogen levels were investigated. The results showed that micro-nano bubble aerated irrigation and nitrogen fertilizer have substantial influence on tillering of early rice, and the effect of N fertilizer was greater than the effect of oxygen. Nitrogen accumulation increased by 6.75-10.79% in micro-nano bubble aerated irrigation treatment compared with the conventional irrigation. The application of N in treatment of micro-nano bubble aerated irrigation and 160 kg N/ha fertilizer used (W₁N₁) was 90% of the treatment of micro-nano bubble aerated irrigation and 180 kg N/ha fertilizer used (W₁N₂), while the yield decreased by only 0.31%. The study indicated that the adoption of an appropriate deficit N rate combine with micro-nano bubble aerated irrigation can be an effective means to reduce non-beneficial N consumption, achieve higher crop yield and N utilization efficiency.

Rational soil phosphorus (P) management is significant to crop production and environment protection. Little information is available on soil Olsen-P balance and critical values in double-crop rice in China. The main aim of the study was to relate soil Olsen-P to apparent P balance and to determine Olsen-P critical value for early and late rice using data from a 29-year study (1984~2012) at the Jiangxi province. The results showed that Olsen-P decreased by 0.12~0.26 mg/kg/year without P addition and increased by 0.56~2.52 mg/kg/year with P fertilization. Olsen-P decreased by 0.30 mg/kg for CK and NK under an average deficit of 100 kg P/ha, and increased by an average of 9.10 mg/kg in treatments with organic manures and were 4.55 times higher than chemical fertilizers with 100 kg/ha of P surplus. The critical values for early and late rice were 22.70 and 22.67 mg/kg, respectively. The average Olsen-P content is 90.89 mg/kg after 29-year application of chemical fertilizer and manures. Therefore, decreasing the amount of total P input and increasing the compost portion should be recommended to improve food production and protect environment in red paddy soils in south China.

In 2004-2009, a small-plot trial was conducted on permanent grassland dominated by Festuca arundinacea Schreb. on the mesohygrophytic site in order to evaluate effects of four levels of nutrition: F₁ = without NPK fertilization, F₂ = P₃₀ + K₆₀, F₃ = N90 + P₃₀ + K₆₀, F₄ = N₁₈₀ + P₃₀ + K₆₀ kg/ha), four levels of cutting intensity (I₁-4, I₂-3, I₃-2, early, I₄-2, late cut) and their interactive influence, i.e. a total of 16 variants on the production of forage dry matter, production of crude protein (CD) and net energy of lactation (NEL) per hectare. The dominant influence of N-nutrition is documented by significant differences in forage dry matter (DM) production between the variants (with the exception of F₁/F₂) ranging from 4.41-4.80 to 8.44-9.83 t/ha. The effect of different exploitation level on the production is subdominant and no significant differences were found either in the production of forage DM(I₁-6.41 - I₂-6.59 - I₃-6.97 - I₄-7.50 t/ha) or in the production of nutrients. Management models to be recommended for the given type of sward with respect to the interactive influence, efficacy of forage production and quality are as follows: (a) three cuts/180 kg N + PK/ha with forage suitable for dairy cows; (b) two cuts/90 kg N + PK/ha with forage suitable for cattle breeds kept for meat.

The aim of the research conducted on eutric brown soil on the experimental facility of Faculty of Agriculture, University of Zagreb in 2012 and 2013, was to determine the optimal sowing density for two cultivars of white lupin (Teodora and Energy) and a cultivar of narrow-leafed lupin (Arabella). The study included three sowing densities: 60, 75 and 90 germinated seeds/m². The cultivars of white lupin achieved significantly higher seed yield, higher 1000 seed weight, higher weight of seeds per plant and higher protein content in the seed, compared to the cultivar of narrow-leafed lupin. The sowing density had no effect on seed yield, but the increase in sowing density above 60 germinated seeds/m² significantly reduced the number of pods, the number of seeds and seed weight per plant.

The purpose of the study was to establish quantitative and qualitative composition of soil-borne microorganisms in the cultivation of carrot. The experiment considered rye, white mustard, buckwheat and sunflower as cover crops and three systems of cultivation. The population of bacteria and fungi having an antagonistic effect towards selected fungi pathogenic to carrot was determined. The greatest total population of bacteria as well as Bacillus spp. and Pseudomonas spp. was observed in the soil when rye was the cover crop. The greatest quantity of fungi was found in the control, a slightly smaller amount - after using sunflower, buckwheat and white mustard. The system of tillage had no effect on the communities of the investigated microorganisms. Rye and white mustard had the most positive effect on the quantity of antagonistic Bacillus spp., Pseudomonas spp., Clonostachys spp., Myrothecium spp., Penicillium spp. and Trichoderma spp. Regardless of the tillage system, the smallest quantity of antagonistic microorganisms occurred in the conventional cultivation of carrot.

An evaluation of the effects of soil structural heterogeneity on maize (Zea mays L.) root system architecture was carried out on plants grown in boxes containing fine soil and clods. The clods were prepared at two levels of moisture (0.17 and 0.20 g/g) and bulk density (ranges 1.45-1.61 g/ml and 1.63-1.79 g/ml). Soil moisture directly affected the probability of clod penetration by maize roots. Primary roots inside the clods manifested morphological deformations in the form of bends. We observed a significant increase of bends per root length at lower soil moisture (P = 0.02). Root diameter and branching density increased, and lateral root length decreased considerably inside the clods. However, once emerging out of the clods and into free soil, values of all three characteristics remained low. While changes in root diameter were caused mainly by clod moisture (P < 0.05), length of lateral roots was related to bulk density (P < 0.01). Branching density was modified exclusively by an interactive effect of both factors (P < 0.05).

A laboratory microcosm experiment was conducted to evaluate the effects of the four single-species (Pinus tabulaeformis (Pt), Pinus radiata (Pr), Cercidiphyllum japonicum (Cj), and Ostryopsis davidiana (Od) litters from southwestern China and mixed pine-broadleaf (Pt + Cj, Pr + Cj, Pt + Od, Pr + Od) litters on soil microbial activities and dissolved organic carbon (DOC). Microcosms with the local typical soil and litterbags containing the eight litter types were incubated with 60% water field capacity for 84 days at 20°C. The results showed that the dynamics of soil microbial parameters and DOC were influenced by the litter types with different initial chemical quality. Due to their initial poor nutrient contents, the Pt and Pr litter treatments always showed lower soil microbial activities and DOC at each sampling compared with the Cj and Od litter treatments. However, compared with the single-species pine litter treatments, the inclusion of broadleaf Cj or Od litter into pine litter significantly increased soil microbial activities, and the concentrations of soil DOC during the whole incubation process. The current work thus provided a good implication for plantation management that it should be appropriate to consider Cj as an ameliorative species or retain Od in the pine plantations to improve soil conditions.

Balancing the use of maize (Zea mays L.) residues for soil amendment and forage is an important strategy for agricultural sustainability. Therefore, the study assessed the impacts of four proportions of maize residues to soil retention (S) and forage (F) on soil total organic carbon (TOC); total nitrogen (TN); carbon/nitrogen ratio (C/N); grain yield, economic benefits and nutritional contents of removed residues. The concentrations of TOC and TN increased when more residue returned, while the C/N ratios were S₁₀₀ + F₀ > S₃₄ + F₆₆ > S₆₆ + F₃₄. Also, crude protein, crude fat, and crude starch in the removed residues were F₃₄ > F₆₆ > F₁₀₀, while the crude fiber and ash contents exhibited the opposite trend. The crop yield improved with residue retention increased, but there were no differences on the economic benefits of the four residue-use systems. The S₃₄ + F₆₆ system maintained a TOC ranging from 11.51 to 13.37 g/kg, a TN from 1.12 to 1.16 g/kg, 92.93% of the annual yields of the S₁₀₀ + F₀ system, and 6.2 t/ha/year of forage. Therefore, the S₃₄ + F₆₆ system can balance the use of maize residues for soil amendments and forage to sustainably develop a household crop-livestock system.

Soil organic matter (SOM) is a major index of soil quality assessment because it is one of the key soil properties controlling nutrient budgets in agricultural production systems. The aim of the in situ near-infrared spectroscopy (NIRS) for SOM prediction in paddy area is evaluation of the potential of SOM and prediction of other soil properties. There are keys for soil fertility and soil quality assessments. A spectral reflectance of 130 soil samples was collected by field spectroradiometer in a region of near-infrared. Spectral reflectance collections were processed by the first derivative transformation with the Savitsky-Golay algorithms. Partial least square regression method was used to develop a calibration model between soil properties and spectral reflectance, which was used for prediction and validation processes. Finally, the results of this study demonstrate that NIRS is an effective method that can be used to predict SOM (R² = 0.73, RPD (ratio of performance to deviation) = 1.82) and total nitrogen (R² = 0.72, RPD = 1.78). Therefore, NIRS is a potential tool for soil properties predictions. The use of these techniques will facilitate the implementation of soil management with a decreasing cost and time of soil study in a large scale. However, further works are necessary to develop more accurate soil properties prediction and to apply this method to other areas.

Changes in the enzymatic activity of soil variably fertilized with NPKCa were investigated in a field experiment carried out in 2005-2010. The study was conducted with a legume plant, i.e. eastern galega (Galega orientalis Lam.). The experiment was completely randomized and carried out in three replications with the following mineral fertilization: control, N, P, K, NPK, NP, NK, PK, NPKCa, PKCa, Ca, NKCa, and NPCa. Mineral fertilization was applied in kg/ha: (N-20, P-50, K-160, Ca-150). The soil samples collected from the Ap horizon (0-30 cm) of the rhizosphere in spring after the 1^st, 2^nd and 3^rd swathing had a pH_KCl in range from 6.55 to 6.93. The activity of acid phosphatase and alkaline phosphatase was at a low level. The highest activity of urease was recorded in the soil fertilized with NPK, whereas the highest activity of dehydrogenases was in the soil fertilized with PKCa.

Carbon dioxide (CO₂) fluxes from agricultural soils have been considered as one of the important environmental impact issue, due to their role in global warming and also its mitigation by carbon (C) sequestration in soils. Substantial scope of C sequestration with the application of inorganic fertilizers and manures has been reported, but the long-term effects of continuous application need to be critically examined. To study the effect of continuous differential application of NPK fertilizers and farmyard manure (FYM) in maize-wheat cropping system, CO₂ fluxes were measured via closed chambers and gas chromatography in a long-term experiment in progress for the past 42 years. The average daily CO₂ fluxes differed significantly amongst various treatments and were 55, 26 and 92% higher in NPK, N and NPK + FYM treatments over the control in the maize crop season and 43, 8 and 83% in the wheat crop season. Highly significant correlation of CO₂ emissions was found with soil organic carbon and total nitrogen in the maize and the wheat crop seasons. Although, CO₂ emissions were higher from long-term inorganic fertilizers and FYM treatments, still they are environmentally sustainable management practices, as they increased soil fertility and crop yields which consequently resulted in higher atmospheric CO₂ capture by plants and carbon sequestration in soils.

Stable isotope ¹⁵N tracer technique was used in combination with artificial rainfall simulation to study the influence of interflow and surface-flow on nitrogen (N) migration loss of soil-plant systems on typical red soil sloping uplands. This study also investigated the utilization efficiency of fertilizer N during different peanut plant growth stages. The results indicated that soil N loss was predominantly via interflow and erosive sediment. Fertilizer N loss during the initial growth stage was mainly through surface runoff, while that occurred as interflow increased from less than 5% to around 16% during the middle and late growth stages. The loss of fertilizer N through surface runoff, erosive sediment and interflow accounted for over 18% of the total N application. The utilization rate of fertilizer N by peanut plants was around 45% through its life cycle, and that 70% of N absorbed by this plant derived from the soil. This highlighted the importance of adopting effective methods to reduce nutrient loss through interflow and surface-flow, the need to increase the utilization rate of fertilizers, and the importance to maintain soil fertility at a relatively high level.

The 28-day incubation experiment was carried out to evaluate the impact of the application of digestate (Dig); digestate with straw (DigSt); pig slurry (Slu) and mineral fertilizer (NPK) on Cd, Cu, Mn and Zn availability, on K₂SO₄-extractable carbon content and on the soil pH value in long-term contaminated soil. At days three and seven of the experiment, the 0.01 mol/L CaCl₂-extractable fractions of Cd, Zn and Mn significantly decreased under organic treatments (Dig, DigSt and Slu) with the most pronounced effect under Dig treatment. The NPK treatment caused the increase of risky element concentrations since day 21 of incubation which was accompanied with pH decrease. The contents of 0.5 mol/L K₂SO₄-extractable carbon were the highest at day 3 and 7 of incubation in organic treatments. The significant correlations between 0.5 mol/L K₂SO₄-extractable carbon and CaCl₂-extractable metal concentrations showed a close relationship between fresh organic matter added in organic fertilizers and risky element availability, suggesting that newly added labile organic matter can form temporary ligands with risky elements and release them later following its decomposition.

It was assumed that the determination of the mineral nitrogen (N_min) content in the 0.01 mol/L CaCl₂ could rely on measurements of single form NO₃^--N, NH₄⁺-N or both, and even including other extractable nutrients. This hypothesis was verified based on some primary data from 17 fields: ten with oilseed rape and seven with maize as indicatory crops during three consecutive seasons in a production farm in Górzno, Poland. The contents of NO₃^--N, NH₄⁺-N, P, K, Mg and pH were measured in soil prior to the spring vegetation start and after a crop harvest (autumn). Phosphorus in spring and NH₄⁺-N in autumn, were variables discriminating against the number of clusters. It was higher in cropping sequences (CSs) with maize than with oilseed rape. The reliability of N_min determination and distribution between clusters in spring based only on NO₃^--N was fully corroborated for maize CSs. In autumn, irrespective of the CS, the decisive factor in N_min prediction and distribution over clusters was the NH₄⁺-N pool. This study resulted in the rating of CaCl₂ extractable nutrients, indicating their availability status, shortage or excess, on the background of the N_min temporary rating.

The depth of sampling is an important factor for evaluating soil stability. The objective of this study was to test soil aggregate particle-size fractions and soil organic carbon (SOC) in water-stable aggregate by vegetation restoration through 0-60 cm soil profile. We collected soil samples in 30 years old Robinia psendoacacia (Rr); Platycladus orientalis (Po); Pinus tabulaeformis (Pt); abandoned land (Ab), and slope cropland (Sc), which were separated into > 2, 2-1, 1-0.25, 0.25-0.053, and < 0.053 mm fractions. The > 0.25 mm water-stable aggregates (WSA) and mean weight diameter (MWD) were calculated in 0-60 cm soil depth. Results showed that soil aggregate fractions (> 0.25 mm) of four vegetation types were significantly (P < 0.05) higher in 40-60 cm soil depth under Po, Pt, and Ab compared with Sc and the SOC distribution in macro-aggregates (> 0.25 mm) under Rr, Po, Pt, and Ab was higher more than 37.7, 92.4, 92.5, 79.1%, respectively in 40-60 cm compared with Sc additionally, > 0.25 mm WSA and MWD was significantly higher in Pt soil in 20-40 cm, 40-60 cm soil depth (P < 0.05). The results demonstrated that soil stability was enhanced and SOC content was increased after converting slope cropland to forest, especially under Pt forest that greatly influenced the subsoil.

Cotton (Gossypium hirsutum L.) is a global major crop with strong tolerance to abiotic stress, but its tolerance to cadmium (Cd) stress is unclear. The objective of this study was to determine the influence of Cd stress on the seedling growth and some physiological properties of cotton. Cotton seedlings with three fully expended leaves were treated with Cd at different concentrations (0, 25, 50 and 100 μmol/L), and seedling growth, chlorophyll (Chl) content, malonaldehyde (MDA) content, photosynthetic rate, superoxide dismutase (SOD) and peroxidase (POD) activity in the main-stem leaves were measured 5 days or 10 days after stress treatment. It was found that with the increase in the Cd concentration, the SOD and POD activity of the stressed seedlings displayed an increase first and then a decrease. The MDA content increased and the Chl decreased, which finally led to a decline in plant height and leaf area. The results suggest that cotton seedlings were adapted to low-concentration Cd stress by the increased protective enzyme activity, but over 50 μmol/L of Cd concentration would exert a significantly inhibitory effect on the photosynthetic properties and protective enzyme activity of the cotton leaves. Cotton plants can be adapted to low Cd stress by increasing the activity of the protective enzymes.

Cattle slurry is commonly used to fertilize grasslands, so its impact on plant composition and herbage properties is important. Cattle slurry at annual rates of 60 (S1), 120 (S2), 180 (S3), and 240 kg nitrogen (N)/ha (S4) was applied to Arrhenatherion grasslands in moderately wet (WS), slopy (SS), and moderately dry (DS) sites cut three times a year over six years, to assess its effects on plant functional types, the Ellenberg N indicator value (Ellenberg N), herbage dry matter (DM) yield, herbage N content and offtake, N nutrition index (NNI), and N use efficiency (NUE). The site-specific changes in an increase in graminoid cover, Ellenberg N, herbage DM yield and N offtake, and NNI along with slurry application rates revealed, while cover of legumes, short forbs, and NUE decreased. In more productive sites (WS and SS), slurry application in the amount of 180 kg N/ha could be suggested as a slurry dose ensuring beneficial agronomic objectives. However, nature conservation requirements via maintaining plant biodiversity were not met. On the contrary, short-term slurry application up to 120 kg N/ha ensured on permeable DS not only sufficient agronomic objectives, but also plant biodiversity conservation requirements.

The decline of soil organic carbon (SOC) has aggravated salinity-related problems in semi-arid irrigation areas of the Awash river basin, Ethiopia. This study aimed at evaluating the performance of potential remediation crops on saline soil and their effectiveness for remediating soil salinity and improving pH, SOC, bulk density (BD) and hydraulic conductivity (HyCo). Rhodes grass (RHG), alfalfa (ALF), sudangrass (SUG) and blue panicgrass (Retz) (BPG) were grown in saline (3-13.9 dS/m) field plots. The crop biomass was incorporated into the soil immediately before flowering. The results show that at high soil salinity levels, BPG and SUG grew well, with the harvesting frequency of BPG being much higher than for SUG. Conversely, the growth of ALF and RHG was strongly inhibited by high soil salinity. Significant (P < 0.05) reduction of soil salinity levels (-3.2 dS/m) and related ionic concentrations, an increase of SOC (0.8% to 1.6%) and improvement of BD and HyCo were observed in BPG plots. The fast-growing nature of BPG in the hot climate of the experimental area resulted in harvests every three weeks and promoted the incorporation of high amounts of biomass to the soil and efficient soil salinity remediation. At moderately saline conditions, ALF also showed a great potential for salinity reclamation (-1.8 dS/m) and SOC accumulation. The cultivation of fast-growing annual crops proved an efficient and low-cost strategy for soil salinity mitigation and the reclamation of salinity-associated soil degradation in irrigation agriculture in Ethiopia.

The investigation was carried out in 2005, on 30 plots chosen in the Central-Eastern part of the Emilia Romagna region, and cultivated with pear, grapevine and vegetable crops under the organic management system. For each crop, 5 plots with a level of calcium carbonate > 10% and 5 plots with a level of calcium carbonate < 3% were selected. For pear and vine, soil analyses were performed at the depths of 0-20 cm and 20-50 cm, for vegetable at the depth of 0-50 cm. Organic matter content was higher in pear-cultivated plots, followed by grapevine and vegetable crops. Copper application rate, from 1998 to 2004, was higher in pear and grapevine than in vegetable plots. Soil total and DTPA-extractable Cu were higher in pear and grapevine than in vegetable-cultivated plots. Soil DTPA-extractable Cu concentration was higher in the upper horizon than at 20-50 cm soil depth. The increase of total Cu in pear and vine-cultivated plots was combined with the increase of soil inactive Cu.

The study was based on soil samples taken after the long-term fertilizer experiment (1974-2014) where different doses of nitrogen and potassium were applied. The experiment was located at the Research Station of the UTP University of Science and Technology in Bydgoszcz (Poland). The long-term application of nitrogen and potassium fertilizers leads to changes in the concentration of mercury, soil acidification, reduction in total organic carbon, total nitrogen as well as affluence of available nutrients (P, K, Mg) and increased mobility of copper and zinc. The significant positive correlation between total mercury content in the soil and the content of N-NO₃, Zn, N-NH₄ and the hydrolytic acidity value were stated.

Minituber production by traditional method is an expensive procedure due to limited productivity. In order to increase the multiplication rate of seed material in vitro, multiple techniques have been assayed in the last decades. The aeroponic system is a soilless culture system, where roots are kept in a dark environment saturated with aerosol of nutrient solution. Aeroponics technology is potentially efficient for specific potato cultivars. The aim of this study was to investigate the multiplication rate of microtubers of national cultivars in aeroponics while maintaining weekly intervals between harvests. The total number of harvests was 14 to 15 depending on year. The results of the experiments were analysed with ANOVA and means were separated with the Tukey's test at 5% P-value. The most important parameter of minituber production, their number, was on average 32.5-36.0 per plant and 1268-1396 per m² depending on cultivar. Number of minitubers was two to three times greater in the case of aeroponic production than by traditional method. A full economic analysis is necessary to prove that this production technique can be put into practice.

Soybean yields can be considerably improved by inoculation with selected Bradyrhizobium japonicum strains and foliar fertilization. An exact field experiment was carried out in 2012-2014 at the Experimental Station of Cultivar Assessment in Przecław, Poland. The test plant was soybean cv. Aldana. The experimental factors were: bacterial inoculant Nitragina (Bradyrhizobium japonicum); foliar fertilization with Mikrokomplex; combined applications Nitragina + Mikrokomplex and the control treatment. Significant effect of Nitragina on an increase in the number of plants prior to harvest, plant height and the number of pods per plant was indicated. Fertilization with Mikrokomplex caused an increase in the number of pods per plant and thousand seed weight. Nitragina + Mikrokomplex increased the number of plants prior to harvest, plant height, the number of pods per plant and thousand seed weight. Seed yield was significantly higher in all the treatments compared to the control (2.31 t/ha). Higher soil plant analysis development values were found after the application of Nitragina + Mikrokomplex, and in the stage of pod development, also after foliar fertilization with Mikrokomplex. Application of Nitragina and Nitragina + Mikrokomplex resulted in an increase in leaf area index and mean tip angle and total protein in seeds. Fe content in seeds was the lowest in the control (69.2 mg/kg) and significantly higher in the other treatments (Nitragina, Nitragina + Mikrokomplex), and Mg content significantly increased after the application of Mikrokomplex and Nitragina + Mikrokomplex.

Regarding the increased surface runoff from production areas, wide-row crops grown on slopes are considered risk crops. By reducing the surface runoff, it is possible to mitigate the negative effects on both the soil and the plants and positively influence the subsequent production, e.g., after application of de-stoning before planting. During this research, the tied ridging method was applied during planting by a two-row planter in both central and tractor trail furrows in potato rows and on the slope of 8.8% compared to a control plot without this treatment. Rainfall and surface water runoff were monitored, and the crop yields were compared. During three monitored years, up to 86% of the runoff water in the central furrows was saved compared to the control, whereas it was up to 72% in the wider furrows for tractor travel. The total yield was increased on the treated area, however, the increase could not be statistically proven.