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The effect of the application of compost and cow manure on nectarine (Prunus persica L.) root growth and survivorship was investigated in a commercial orchard during the growing seasons 2003, 2004 and 2005. Our main objective was to determine whether compost affects root dynamics differently than cow manure. The experiment was a complete randomized block design with four replicates of two treatments: cow manure and compost applied at planting in 2001 at 10 t dry weight (DW)/ha and from 2004 at the rate of 5 t DW/ha. The compost fertilization represented a yearly rate of 120 kg N/ha, while cow manure was approximately 80 kg N/ha/year. Both root growth and survival were evaluated at 20-day intervals during the growing season by the minirhizotron technique. Cow manure increased the production of new roots compared with compost (P ≤ 0.001). Roots were mainly produced at a depth of 21-40 cm for compost and 61-80 cm for cow manure. The root lifespan was longer in compost than in cow manure treated trees (P ≤ 0.05) and was strongly affected by depth. No differences were observed in root length and diameter.

Three-year strict experiments with winter rapeseed were conducted in three experimental stations. In the research, winter rape fertilization with elemental sulphur (S) in the doses: 20, 40 and 60 kg S/ha, boron (B) - in the dose of 2 kg B/ha and copper (Cu) - 5 kg Cu/ha were applied. Microelements were introduced separately, in treatments B and Cu, as well as in combination B + Cu. The experimental soils featured low content of sulphate sulphur SO₄^2--S and boron, medium and low copper content. Rapeseed fertilization with sulphur, boron and copper resulted in their increased concentration in plants. Sulphur at 40 and 60 kg S/ha doses affected the increase in oilseed rape grain yield by 11-12% compared to the not fertilized treatment. The dose of 20 kg S/ha did not show any significant influence on yield. The yield increased by more than 10% in the comparison to the treatment without B and Cu, was obtained due to boron, as well as combination of boron and copper fertilization. A significant increase in fat content, in relation to not fertilized treatment, ranking from 1.0-1.4% dry matter, was recorded after fertilization with the highest sulphur dose - 60 kg S/ha, as well as after application of boron and copper fertilization.

The effect of simultaneous intercropping of winter wheat (Triticum aestivum L.) with different legumes of faba bean (Vicia faba L.), pea (Pisum sativum L.), and purple clover (Trifolium incarnatum L.) on selected production and qualitative parameters of wheat was evaluated in field trials conducted both in organic and conventional cropping systems, in comparison with pure sown wheat. Wheat intercropped with legumes achieved higher grain yield compared to pure sown wheat for an average of two years. However, in organic cultivation, the positive effect of intercropping on wheat yields was more pronounced. In addition, a strong influence of the year was noted. In 2021, in the organic cropping system, the most yielding intercropped wheat (especially with pea and bean) achieved 114-117% higher yields compared to pure sown wheat (in the previous year of 2020, it was usually only about 102-106%). In the conventional cropping system, the effect of intercropping on wheat yield was significantly weaker, and in 2021, wheat intercropped with legumes reached even lower yields than pure sown wheat in some cases. In terms of sowing methods (both in organic and conventional cropping systems), mixed sowing with individual legumes significantly exceeded the yields of wheat grown with legumes in separate, alternating rows. As regards quality parameters, wheat intercropped with legumes reached in comparison with pure sown wheat usually had higher crude protein content in wheat grain dry matter and higher values of Zeleny sedimentation.

This study compares the effect of application of digestate, straw, cattle slurry and inorganic fertilizers on crop yield and soil organic matter content. Total organic carbon (C), total organic nitrogen (N), hot water soluble C, microbial biomass C and hydrophobic soil components were evaluated in soil from the field experiment in Prague-Ruzyně (Orthic Luvisol, clay loam) with winter wheat. All fertilized treatments significantly increased grain yield above the level of non-fertilized control (5.68 t/ha), and the sequence was as follows: digestate (9.88 t/ha) > NPK(9.80 t/ha) > cattle slurry (9.73 t/ha) > digestate + straw (9.35 t/ha). Average organic C content in the soil ranged from 1.668-1.704% and the effect of different fertilization was not significant. The highest increase of microbial biomass C was recorded in digestate + straw (43.2% increase compared to control). Highly significant correlations were found between hydrophobic soil components and hot water soluble C (r = 0.988; P ≥ 0.05) and microbial biomass C (r = 0.964; P ≥ 0.05). Total organic N content ranged from 0.157-0.160% and differences among treatments were insignificant. Fertilization with digestate itself brings an effect in increasing crop yield, but does not improve the level of soil organic matter significantly.

This study investigated the influence of soil undergoing different crop rotations on the CH₄, CO₂ emissions, and decomposition of rice straw. The studied soil undergoing crop rotation systems were rice-rice-rice (SR) and baby corn-rice-mungbean (SB). Two main microcosm set-ups: anaerobic (SR-AN, SB-AN) and aerobic (SR-AE, SB-AE) conditions. Litter bags containing rice stems were inserted into the soil and recollected at different time points for chemical analysing and the gas sampling was collected to measure the CO₂ and CH₄ emissions. The results indicated that the total carbon (TC) decreased around 30%, and the TC removal in anaerobic was significantly higher than in aerobic conditions. The residue cellulose content varied in a range from 68.2% to 78.6%, while the hemicellulose content varied from 57.4% to 69.3% at day 50 after incorporation. There were no significant differences in the total nitrogen removal, cellulose, hemicellulose, and lignin contents among the microcosm set-ups. CO₂ emission increased in all the microcosm set-ups with the treatments without rice straw (CTSR, CTSB) in both aerobic and anaerobic conditions. CH₄ release in the SR-AN treatments did not differ significantly compared with the SB-AN treatments. This study confirmed that the decomposition of rice straw residues is faster in the anaerobic paddy soil condition compared to the aerobic crop rotation condition.

The aim of this study is to define data sources and propose methods for effective and secure data management in an agricultural enterprise in the context of using data for decision support. Current developments in information and communication technology (ICT) have contributed towards the increase in the amount of generated data in various fields. The main data sources for agricultural enterprises are the farm itself, suppliers, government, market, and research. The use of smart solutions, artificial intelligence, and other innovative practices in agriculture is discussed at many conferences, in various journals, strategies and project plans. Data is the essential raw material for all these solutions. Large amounts of data cannot be analysed efficiently with spreadsheet programs. Currently, there are trends in the use of data, for example, in business intelligence (decision-making systems), e.g. tools using online transaction processing (OLAP) or process automation or the possibility of e.g. tracing the origin of food. The availability and possibility of creating large data sets bring many challenges related to managing that data. To effectively manage farm data, it is essential to have a well-developed data management plan (DMP) used to formalise the processes related to handling. A DMP mainly addresses archiving, backup, licensing and other important aspects of data management. The challenges and developments in farm data management include incorporating artificial intelligence into data analysis and security. Food is classified as an "Entity of Critical Importance" in the NIS2 EU Directive, which also deals with cybersecurity issues.

Research was conducted to determine the content of total polyphenols (TP) in table potato tubers obtained in a three-year field experiment arranged as a split-plot design with three replicates. The first experimental factor included two potato cultivars: Oberon and Malaga, the second one being an application of the following biostimulants: PlonoStart, Aminoplant, Agro-Sorb Folium and the herbicide Avatar 293 ZC (clomazone + metribuzin). The polyphenol content of potato tubers was determined in the fresh tuber mass by the spectrophotometric method with the Folin-Ciocalteu reagent. The tuber content of polyphenols was affected by cultivars and test biostimulants. Cv. Malaga accumulated more polyphenols than cv. Oberon. Biostimulants + herbicide significantly increased an accumulation of polyphenolic compounds compared with tubers cultivated in the control unit which was not treated with the test products.

The effects of long-term various organic fertilisers application on ecosystem respiration components and net carbon budget have rarely been investigated in a hillslope agricultural ecosystem. Hence, we measured the rates of plant autotrophic (R_a) and soil heterotrophic respiration (R_h) from 2011 to 2012 with five treatments: no fertiliser (CK); mineral fertiliser (MF); MF combined with swine manure (MFS); MF combined with crop straw (MFC), and swine manure (SM). Our results confirm that R_a was found to be more temperature-moisture sensitive than R_h, whereas R_h was more temperature sensitive than R_a. Soil microbial biomass carbon (MBC) is a major factor influencing the temperature sensitivity coefficient of Rh (Q₁₀), thereby application of organic fertilisers combined with mineral fertilisers (MFS and MFC) significantly increased annual by 19.3% and 17.2% compared with MF treatment. Annual carbon emissions via R_h and R_a under MFS, MFC and SM treatments were increased by 24.6, 28.5, 48.8% and 6.6, 10.6, 1.8%, respectively compared with MF treatment (4.6 and 23.2 t C/ha/year). Net primary production (NPP) under MFS, MFC and SM treatments were increased by 5.4, 6.01, and 15.6% relative to MF treatment (13.6 t C/ha/year), respectively, and the corresponding net ecosystem carbon budget (NECB) increased by 121.2, 172.8, and 342.4%. Our findings establish that long-term organic fertilisers application increase plant autotrophic, heterotrophic respiration and net ecosystem carbon budget, which can increase the carbon sink function. Overall, crop straw combined with mineral fertiliser is a feasible agronomy practice to increase carbon sink function, reduce soil erosion and maintain crop yield.

One of the latest environmentally friendly methods in soybean production technology is the pulsed electromagnetic field of low frequencies (PEMP). The paper presents the results of the influence of electromagnetic stimulation of soybean seeds on grain yield, protein and oil yield, depending on different agroclimatic conditions, exposure time and frequency. In the 2012–2017 research period, the soybean cv. Valjevka was used in the Institute of Field and Vegetable Agriculture experimental field, Novi Sad, Serbia. Immediately before sowing, the seeds were subjected to PEMP treatment, with a pulse generator and a tape applicator, in the following variants: electromagnetic field frequencies of 16, 24 and 30 Hz, and exposure time of 0, 30 and 60 min. The most successful variant of seed stimulation for all three examined parameters was at 16 Hz and 30 min, where the research results show that this measure can increase the examined parameters by more than 10%. The average yield of grain for all years of research with seed stimulation was 4.85% (3 338 kg/ha) compared to the control (3 203 kg/ha). The average grain protein yield in the treatments with PEMP was 1 315 kg/ha, which was 4.26% higher compared to the variant without PEMP (1 260 kg/ha), and the treatment was 4% higher in the average oil yield, 703 kg/ha compared to the control 676 kg/ha. Also, the analysis of the mutual dependence of the indicators is in a positive correlation, which is essential for plant breeding and the development of new technologies, which have economic justification, are safe for use and have a positive impact on adverse effects such as drought.

To assess the response of two safflower genotypes to auxin foliar application under late-season drought stress using a factorial split-plot experiment with the randomised complete block design, a two-year experiment (2016-2017 and 2017-2018) was conducted in Iran. The watering regime as specified in two levels including, regular irrigation and drought stress in main plots and two safflower genotypes and auxin foliar application in two levels including non-foliar application (control) and auxin foliar application at a concentration of 30 ppm were categorised in subplots. Drought stress at the seed filling stage reduced the safflower seed and oil yield. Moreover, a significant drought-induced decrease in linoleic acid, palmitic acid and behenic acid content, as well as an increase in oleic acids, was observed in two safflower genotypes. Among two safflower genotypes, the early maturing genotype less affected by drought and Goldasht had higher seed yield than the Padideh by 814 kg/ha, respectively. Auxin foliar application alleviates the adverse effects of drought, which led to an 18% increase in seed yield and components. However, the auxin application had no effect on the safflower seed oil content but palmitic acid content was affected by auxin foliar application. Generally, safflower along with auxin application can be recommended to develop safflower cultivation in semi-arid areas.

Biochar is a carbonaceous material derived from the pyrolysis of carbon-rich biomass that has attracted increasing research and attention because of its ability to enhance soil carbon storage, increase soil fertility, fix and transform pollutants in soil, and improve the soil environment. These enhancements directly or indirectly affect soil microorganisms’ metabolic activities and community structure. This paper reviews the effects of biochar on soil physicochemical properties, enzyme activities, nutrients, contaminants, and related microbial activities. In addition, this work summarises the possible mechanisms involved in the interaction between biochar and microorganisms and the potential hazards associated with biochar use. Finally, this study aims to provide a theoretical basis for future related research.

This study was aimed to determine the impact of risk element content on the prevalence of the selected microbial groups in industrial soils of one of the steelworks in Poland. The concentration of heavy metals: Cd, Cr, Cu, Hg, Fe, Ni, Pb and Zn along with soil pH and the number of mesophilic bacteria, fungi, actinomycetes and Azotobacter was assessed in 20 soil samples. The limit concentrations of Cd, Pb and Zn were exceeded in five sites. However, even in these strongly contaminates sites, the studied microorganisms were abundant. The correlation between the concentration of heavy metals and microbial numbers was very weak and statistically insignificant. High numbers of fungi were observed in the contaminated sites, which was particularly interesting in one of the sites, strongly contaminated with Cd, Pb and Zn.

The experiment aimed to obtain a quadratic regression mathematical model of the comprehensive evaluation score of yield, quality, and four macroelements (N, K, P and Ca). The suitable nutrient solution was chosen and verified via computer simulation of the model and the highest comprehensive score in all treatments. Results showed that P, K and Ca had a positive effect on the comprehensive evaluation value of tomato, whereas N showed a negative effect. The optimal formula calculated using the regression equation could promote high-yield and high-quality tomato. The single-plant yield, soluble protein, vitamin C, total sugar, lycopene, and elemental utilisation of K and Ca in the tomato were 13.93, 78.95, 3.29, 20.98, 51.91, 16.69 and 24.14% higher than those in the special formula treatment of Japanese Yamazaki tomato, respectively. In summary, the optimal nutrient solution formula of tomato cultivation was obtained, in which the N, P, K and Ca levels were 24.83, 4.50, 9.49 and 5.73 mmol/L, respectively.

The aim of the study conducted in 2019-2021 was to determine the effect of biostimulants and growth regulators on the yield size and structure, as well as the chemical composition of edible potato tubers. The cultivar evaluated was Vineta. Asahi SL, Kelpak SL, Aminoplant, Tytanit, gibberellic acid (GA3) and Moddus 250 EC were applied in potato cultivation. The application of biostimulants Asahi SL and Tytanit increased the total and marketable tuber yield, as well as the average tuber weight. Aminoplant had a beneficial effect only on the marketable yield, while Moddus 250 EC decreased tuber yield and mean tuber weight, especially under conditions of high rainfall. Biostimulant Asahi SL caused a decrease in the number of tubers formed, while gibberellic acid stimulated tuberisation. Both preparations increased the share of deformed tubers in the total yield. The effect of biostimulants and growth regulators on the formation of the chemical composition of potato tubers was multidirectional. Tytanit increased protein content in tubers, while the remaining preparations, with the exception of the growth regulator Moddus 250 EC, decreased the amount of this component. GA3 and Moddus 250 EC decreased the content of crude fibre and, in the case of Moddus 250 EC, also the content of mineral components. The highest concentration of nitrates (V) was characteristic for potato tubers treated with Asahi SL and the lowest for those treated with Moddus 250 EC.

The influence of toxic elements, such as arsenic (As), cadmium (Cd), lead (Pb), and zinc (Zn), in the root zone of As-hyperaccumulator Pteris cretica 'Albo-lineata' and non-As-hyperaccumulator P. straminea, on the enzymatic activity of β-glucosidase, dissolved organic carbon (C) in soil, toxic element accumulation in fern roots, and root biomass were evaluated in a pot experiment. Ferns were cultivated in soils from the locality of Suchdol (control) and Litavka (high contamination) for six months. For all toxic elements, an increasing trend in their contents in the roots was observed with soil contamination for both ferns. Differences between ferns were observed in As and Zn accumulation. Pteris cretica had a significantly higher As accumulation than P. straminea. Zinc accumulation in the roots showed an opposite trend. A significant difference between ferns was confirmed in the dissolved organic C content. Our results showed a significantly higher content of dissolved organic C in the P. straminea root zone than in P. cretica. The significant effect of toxic elements in the soil on β-glucosidase activity was observed. Toxic elements inhibited β-glucosidase activity in the root zone of P. cretica, and an increase in P. straminea was determined in the Litavka soil. The results suggest a higher sensitivity of P. straminea to toxic element contamination in soil, leading to increased β-glucosidase activity and increased dissolved organic C content.

This study quantifies the effects of weather conditions, irrigation, and plant age on yield and alpha-acids content of Czech hop cultivars Saaz, Sládek, Premiant and Agnus in a 25-year long period, i.e., from 1993 to 2018. The yields of Czech hop cultivars were increasing for the first three years of plant age until they stabilized and then started to decline slightly for 15 to 20 years until they reached the optimal time for replanting. The highest alpha-acids content in hop cones was achieved in the first year of cultivation, followed by a logarithmic decline in the upcoming years. Rainfall was the most significant factor that positively influenced the yield of Saaz hops with correlations of r = 0.59 and 0.61 (P < 0.01) for total seasonal rainfall (April-August), 0.65 (P < 0.001) and 0.60 (P < 0.01) for daily rainfall above 3 mm, 0.37 (P < 0.05) and 0.58 (P < 0.01) for rainfall in May and 0.50 (P < 0.01) and 0.32 (P < 0.05) in July in the Saaz region and the Stekník farm, respectively. The yield of cultivars Sládek, Premiant and Agnus was not statistically influenced by the amount of precipitation, but there was a positive effect of irrigation level on yield increase with correlations 0.58 (P < 0.01), 0.55 and 0.49 (P < 0.05), respectively. High air temperatures during summer were the most significant factor that negatively influenced the alpha-acids content with the correlations ranging from -0.56 to -0.83. However, cv. Agnus showed a stable weather-independent alpha-acids content.

Considering the improvement of acacia species growth in arid and semi-arid environment, a pot experiment was conducted to evaluate the role of arbuscular mycorrhizal fungi (AMF); Funneliformis mosseae (syn. Glomus mosseae), Rhizophagus intraradices (syn. Glomus intraradices) and Claroideoglomus etunicatum (syn. Glomus etunicatum) on growth and drought tolerance of Acacia seyal Del. seedlings under drought cycles (7, 14, 21 and 28 days). AMF-inoculated seedlings showed a clear colonisation percentage (36-68%). AMF treatment significantly improved seedlings shoot and root growth under all drought cycles compared to non-AMF control seedlings. Moreover, AMF treatment enhanced seedlings drought resistance by increasing root surface area (root length increased by 483.76% and root tips number increased by 1 463.94% under 28 days of drought cycle), there was a strong linear relation between proline accumulation, AMF and drought stress (proline content decreased in treated seedlings by 31.3% and 14.3% and increased by 97.5% and 80.4% in untreated seedlings under drought cycles of 21 and 28 days, respectively). In conclusion, the AMF inoculation improved growth and enhanced drought tolerance of A. seyal seedlings and can be used as a natural biostimulator for acacias seedlings establishment in arid areas.

A field campaign was conducted using six treatments under the summer rice-winter wheat cultivation system to evaluate the response of soil greenhouse gas (GHG) emissions to long-term differentiated fertilisation regimes. The treatments included control, phosphorus plus potassium, nitrogen only, nitrogen plus phosphorus (NP), nitrogen plus potassium, and NP plus potassium (NPK). Compared to the control, mineral fertilisation increased CH₄ emissions during the rice season by 69% to 175%. Phosphorus amendment also enhanced seasonal CO₂ emissions by 21% to 34% when compared with the treatments without receiving P, while combined use of P and potassium suppressed seasonal N₂O emission to the same level of control. Net CO₂ and N₂O emissions from the dried fallow and wheat seasons and CH₄ emissions from the flooding rice season dominated annual budgets of individual GHGs. All of the soils under different treatments were net sources of global warming and the overall net global warming potential ranged from 9 799 to 14 178 kg CO₂ eq/ha/year with CO₂ emission contributing 52% to 76%, CH₄ contributing 20% to 40% and N₂O occupying the rest. The annual maximum grain yields and minimum GHG intensity was observed at the NPK treatment, suggesting it to be the environmental-friendly optimum fertilisation regime.

Sustainable cropping systems require efficient usage of fossil energy. This study performed on a long-term field experiment in the Pannonian Basis investigated the energy efficiency of four tillage systems (mouldboard plough (MP), deep conservation tillage (CT_d), shallow conservation tillage (CT_s) and no-tillage (NT)) for sugar beet and soybean production, taking fuel consumption, total energy input (made up of both direct and indirect inputs), crop yield, energy output, net-energy output, energy intensity and energy use efficiency into account. The input rates of fertiliser, chemical plant protection, and seeds were set constant across years; whereas measured values of fuel consumption were used for all tillage treatments. NT required a considerably lower energy input than MP and CT_d as no fuel is needed for tillage and just slightly more fuel for additional spraying of glyphosate. Anyhow, the energy efficiency parameters did not differ between tillage treatments, as theses parameters were mainly determined by energy output, which was considerably higher than the energy input. However, year effects on the energy efficiency were observed for both crops. Nitrogen fertilisation and diesel fuel consumption were identified as the most energy-intensive inputs. Consequently, the energy input for sugar beet was higher than that for soybean, which was identified as a low-input crop. But sugar beet attained a more than 4 times higher net-energy output, a 2.5 times higher energy use efficiency, and an energy intensity for yield production of less than 3 times those of soybean.

The production of summer maize is greatly affected by nitrogen (N) sources through regulating root growth and distribution. Four N treatments in the field experiment were designed as UAN (urea ammonium nitrate solution was applied under traditional side-dressing method), urea (urea was applied under traditional side-dressing method), UWFI (UAN was applied underwater and fertiliser integration technology) and CK (no N applied). The results showed that the root length density, surface area density and volume of DH605 (mid-late hybrid) and DH518 (mid-early hybrid) under UWFI were higher than other treatments, especially in shallow layers. The root absorption area of each soil layer under N application treatments varied with the growth stage. The grain yield and the accumulations of N, P and K in the shoots showed the trend of UWFI > UAN > urea > CK. Compared with UAN and urea, the nitrogen agronomic efficiency of UWFI treatment increased by 40.5~78.6%, and the nitrogen partial factor productivity increased by 4.75~7.61%. Consequently, rational application of UAN would improve root traits, nutrient uptake and utilisation, and yield of summer maize.

The ameliorative effects and its mitigation mechanisms of selenium (Se) on cadmium (Cd) toxicity in cucumber seedlings were studied through hydroponic experiments. Cd and other mineral nutrient concentrations, antioxidant enzyme activities, and antioxidant contents in cucumber were studied. The results revealed that exogenous Se significantly decreased the Cd concentrations in all tissues, especially in the leaves. Moreover, exogenous Se (Cd + Se) could increase Zn, Na, leaf Cu, stem/root Fe, stem/root Ca, and stem/root Mg concentrations; and reduce leaf Mg concentration, compared with Cd alone treatment. Additionally, the application of Se ameliorated the toxicity of Cd by harmonising the activities of antioxidase, such as Cd + Se treatment reduced Cd-induced increase of superoxide dismutase, glutathione peroxidase, leaf/stem ascorbate peroxidase (APX) activities, which resulted in the significant decrease of the content of hydrogen peroxide, and malondialdialdehyde; increased root APX, and glutathione reductase activities. In addition, the content of nonenzymatic antioxidants such as root-reduced glutathione and oxidised glutathione was significantly increased by adding Se under Cd stress. Also, exogenous Se enhanced the total antioxidant capacity in terms of cupric-reducing antioxidant capacity and decreased total phenols, flavonoids, and leaf/root proline contents under Cd stress. In general, 3 μmol/L Se was conducive to plant growth and improved the cucumber's ability to alleviate Cd stress.

To investigate how clipping (CL) regulates the effects of nutrient addition, an experiment, including CL and nitrogen (N) addition, was conducted in an alpine meadow. Nitrogen treatment increased community coverage (48-113% higher than the control) and aboveground biomass (29-117% higher than the control), which was mainly attributed to grass growth. Both N and N + CL treatments showed a tendency to reducing species richness, while significant reduction only occurred in 2016 and 2017 in CL treatment. Clipping showed a tendency to decrease community cover (3-37% lower than the control) and aboveground biomass (2-34% lower than the control), while N + CL treatment had no effect, indicating that clipping can eliminate the simulated effects of N addition. Nitrogen addition significantly increased soil inorganic N (SIN, 528-1230% higher than the control), while SIN in N + CL was 25-48% lower than N treatment. The decrease in stimulated effects in N + CL was attributed to SIN decrease, which resulted from the aboveground biomass removal by clipping. Our results show that clipping can take away aboveground biomass and cause soil nutrients to decrease, which slows down the degraded grassland recovery. This suggests that grazing exclusion may eliminate the effect of nitrogen deposition on aboveground production in alpine grasslands.

We studied the dynamics of soil organic carbon (SOC)-pool mineralisation in agricultural soil. A laboratory incubation experiment was conducted using the soil from a long-term experiment involving the following fertilisation regimes: no fertilisation (CK); mineral (NPK); organic (M), and combined organic-inorganic fertilisers (MNPK). SOC mineralisation rate decreased as follows: MNPK > M > NPK > CK. Cumulative SOC mineralisation (C_m) ranged between 730.15 and 3 022.09 mg/kg in CK and MNPK, respectively; 8.81% (CK) to 20.45% (MNPK) of initial SOC was mineralised after a 360-day incubation. Soil C_m values were significantly higher under NPK, M, and MNPK compared to those under the CK treatment. Dynamic variation in C_m with incubation time fitted a double exponential model. Active carbon pools accounted for 2.06-6.51% of total SOC and the average mean resistant time (MRT₁) was 28.76 days, whereas slow carbon pools accounted for 93.49-97.94% of SOC, with an average MRT₂ of 8.53 years. The active carbon pool in fertilised soils was larger than in CK; furthermore, it was larger in M- and MNPK- than under NPK-treated plots. SOC decomposed more easily in long-term fertilised plots than in non-fertilised plots.

The tillage depth plays a critical role in solving soil compaction - a global problem of soil degradation. However, to date, there are few research reported about tillage depth, and the standard of optimum tillage depth is lacking. Therefore, we conducted a meta-analysis to quantify the effect of tillage depths on crop yield across a global scale, and then to analysis their influence factors such as local climate, soil properties, and managements. Moreover, a global distribution of the optimal tillage depths was estimated by using a random-forest model. Overall, our result demonstrated that crop yield first increased within tillage depths from 25 to 35 cm, and then reduced under higher depth of deep tillage compared to conventional tillage, according to 1109 wheat, maize and soybean (WMS) yield observations from 202 studies and 109 publications. Visibly, 35 cm hence became the optimum tillage depth of WMS across the world, while it varies with different regions. Furthermore, higher crop yields observed in areas with a humid climate, high clay contents, and large bulk density under the optimal depth 40, 35 and 45 cm, respectively. In contrast, a lower yield was observed in areas with arid climates, silty and sandy soils, and lower bulk density within optimal depth of 25 cm, 30 cm, and 25 to 35 cm. Human management efforts, including fertilizer addition, irrigation, straw returning, and changing of cropping system or crop species mostly increased the crop yield under deep tillage. Particularly, our meta-analysis indicated that straw returning needs a greater depth. Finally, we predicted the distributions of optimum depths, which showed that 30 and 35 cm were the optimum tillage depths in the temperate and tropical regions, and the total crop yields of global WMS increased by 2689 million tons per year under the optimal tillage depth, compared with the conventional tillage.

Phenolic compounds (PCs) - with special reference to secondary plant metabolites - were characterised in two Mediterranean olive groves (Olea europaea L.). Representative pedological profiles were dug to identify and characterise the pedotype. Qualitative and quantitative analyses were carried out on soil core samples gathered at fixed depths (0-20 cm and 20-40 cm) and olive leaf methanol extracts by high-performance liquid chromatography with ultraviolet detection. The total PCs content reflected the soil organic carbon distribution, especially carbon of humic and fulvic acids, corroborating their crucial role in humification pathways. Among the analysed plant secondary metabolites, luteolin-4'-O-glucoside and verbascoside were the most abundant in leaves and soils, respectively. Most of the easily hydrolysed/metabolised phenols were not found in soils. Rutin and verbascoside, despite containing glucose, strongly persisted in the soil environment, probably due to their allelopathic effect. Oleuropein was not found in soils because it is highly soluble and mobile in the soil environment. Furthermore, the presence of clay in soil seemed to determine the accumulation of specific PCs. Our data suggest that PCs persistence in soil seems to be mainly determined by a balance between physicochemical and biochemical instability and allelopathic stability rather than their abundance in the plant.

Knowledge about the spatio-temporal variability of soil chemical and biological properties is crucial in evaluating their structure-function relationship and their impact on ecosystem functions. A study was conducted in order to evaluate the spatial variability of nitrogen (N) forms and N-cycle enzymes of a Phaeozem located in the Northwestern Poland. Fifty soil samples were collected every 10 m from the area of 90 × 40 m that was selected from an 80 ha agricultural field after the harvest of winter wheat. The samples were analysed for total nitrogen (N_tot); mineral nitrogen (NO₃^--N, NH₄⁺-N) and the activities of the N cycle enzymes - urease (UR), nitrate reductase (NR) and arginine deaminase (ADA). The coefficients of variation were low for N_tot content and UR activity, while a moderate variability was noted for mineral N and ADA activity and a high one was noted for NR activity. Most of the properties revealed a contribution of random variance (nugget effect) in total variability (sill), while only N_tot and ADA activity were determined by the structural variance. The effective ranges were from 11.9 m for NO₃^--N to more than 50.3 m for NH₄⁺-N. Kriged maps showed that every property revealed a different distribution on the study area. The significant variability of the studied properties should be taken into account in soil management practices. Additionally, this knowledge would contribute to a better understanding of the nitrogen transformation in soil and functioning of the ecosystem.

A 22-year (1990-2012) field experiment was conducted to assess the effects of different fertilization and cropping regimes on the quantitative changes of total N and organic N forms in the topsoil (0-20 cm) and subsoil(20-40 cm) of a Mollisol in Northeast China. This study included nine fertilizer treatments on maize monoculture [no fertilizer (CK), N, NP, NK, PK, NPK, NPK combined with maize straw (NPKS), NPK combined with pig manure (NPKM), and 1.5' the rate of NPKM (1.5NPKM)] and one fertilizer treatment with maize-maize-soybean rotation (NPKMR). Compared with the CK treatment, the application of mineral fertilizers alone or in combination with straw generally had no significant effect on the contents of total N and organic N forms, whereas the combined application of mineral fertilizers with manure significantly increased their contents. Manure levels and cropping regimes had no significant effect on the total N content in the topsoil. By contrast, the hydrolysable unknown N content significantly increased with the increasing manure levels, and the amino sugar N content was significantly lower in rotation than in monoculture treatment. Our results imply that manure application integrated with continuous maize cropping can be considered as an optimized strategy for improving soil fertility.

The present study was carried out in 2016-2017 to assess the effect of subsoiling depth on the soil bulk density, stability of soil structure, soil physical properties and summer maize yield based on a field experiment started in 2015. Four tillage depths were studied: conventional tillage 25 cm (CT₂₅); subsoiling tillage 30 cm (ST₃₀); subsoiling tillage 35 cm (ST₃₅) and subsoiling tillage 40 cm (ST₄₀). The results showed that at the 20-50 cm depth ST₃₀, ST₃₅ and ST₄₀ decreased the mean soil bulk by 4.59, 7.13 and 8.27%, respectively, and at the 0-40 cm depth reduced soil compactness by 17.62, 23.63 and 36.42%, respectively, as compared to CT₂₅. ST₄₀ reduced soil compactness in the 0-40 cm soil layer under conditions of relative drought (during the maize season growing season of 2016), ST₃₅ and ST₄₀ increased macroaggregates (> 0.25 mm), improved the stability of the aggregate structure (geometric mean diameter and mean weight diameter) (20-40 cm), increased soil water storage capacity at 40-60 cm and increased maize yield by 7.89% and 8.91%, respectively. Considering the improvement of soil properties and crop yield, ST₃₅ was the optimum method to increase maize yield and modulate soil physical properties in the North China Plain.

The migration and transformation of soil phosphorus (P) are essential for agricultural productivity and environmental security but have not been thoroughly elucidated to date. A 10-year field study was conducted to explore the effects of conventional tillage (CT) and no-tillage with maize residue management (NT-0, NT-33%, NT-67% and NT-100%) on P contents and phosphatase activities in soil layers (0-5, 5-10, 10-20 and 20-40 cm). The results showed that soil available P content and phosphatase activities were higher in no-tillage with maize residue than CT. Soil moisture and pH were significantly positively correlated with soil available P. Higher organic P contents and lower inorganic P contents in the 0-5 cm soil layer were found in the treatment NT-67% compared with other treatments. According to the structure equation model, the source of available P was inorganic P in NT-33%, while organic P in NT-67%. This study demonstrated that the variation of dominant mechanisms involved in soil P migration and transformation were dependent on residue input amounts, and NT-67% might play an important role in the maintenance and transformation of soil organic P.

The aim of this study was to determine the heavy metals concentrations in soil, inflorescences of Brassica napus and rapeseed honey sampled from some regions of north-eastern Bulgaria. Thirteen locations were selected for experimental studies. The soils, plants and honeys samples were taken from conventional beekeeping areas away from major industrial pollutants. The median amounts of elements in the soil samples (mg/kg DW) are 1.1246 for Fe(s), 0.7048 for Al(s), 0.5636 for Pb(s), 0.1658 for Cu(s) and 0.0148 for Zn(s). The median amounts of heavy metals measured in the inflorescences of Brassica napus (mg/ kg DW) are 5.5430 for Fe(p), 2.9095 for Zn(p), 1.3225 for Pb(p), 0.2593 for Cu(p) and 0.2105 for Al(p). The median heavy metals concentrations in  tested honey (mg/kg DW) are 1.0026 for Fe(h), 0.1849 for Al(h), 0.1832 for Pb(h), 0.1250 for Zn(h), 0.0702 for. Cu(h). The relationship between the heavy metal in soil, plants and honey was investigated using the Spearman’s rank correlation coefficient. Significant differences in the concentrations of Fe(s), Al(s) and Pb(s) in soils, Fe(p) and Zn(p) in the plant samples, Fe(h) in honey samples from the different locations were found. The heavy metal content tested in honey did not pose a risk to human health.