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Land use change may modify key soil attributes, influencing the capacity of soil to maintain ecological functions. Understanding the effects of land use types (LUTs) on soil properties is, therefore, crucial for the sustainable utilization of soil resources. This study aims to investigate the impact of LUT on primary soil properties. Composite soil samples from eight sampling points per LUT (forest, grassland, and arable land) were taken from the top 25 cm of the soil in October 2019. The following soil physicochemical parameters were investigated according to standard protocols: soil organic matter (SOM), pH, soil moisture, NH4 +–N, NO3 –N, AL-K2O, AL-P2O5, CaCO3, E4/E6, cation exchange capacity (CEC), base saturation (BS), and exchangeable bases (Ca2+, Mg2+, K+, and Na+). Furthermore, soil microbial respiration (SMR) was determined based on basal respiration method. The results indicated that most of the investigated soil properties showed significant difference across LUTs, among which NO3 –N, total N, and K2O were profoundly affected by LUT (p ≤ 0.001). On the other hand, CEC, soil moisture, and Na+ did not greatly change among the LUTs (p ≥ 0.05). Arable soils showed the lowest SOM content and available nitrogen but the highest content of P2O5 and CaCO3. SMR was considerably higher in grassland compared to arable land and forest, respectively. The study found a positive correlation between soil moisture (r = 0.67; p < 0.01), Mg2+ (r = 0.61; p < 0.01), and K2O (r = 0.58; p < 0.05) with SMR. Overall, the study highlighted that agricultural practices in the study area induced SOM and available nitrogen reduction. Grassland soils were more favorable for microbial activity.

Open access

Abstract

The enzymatic conversion of sucrose to fructo-oligosaccharides (FOS) catalyzed by Pectinex Ultra SP-L, a commercial enzyme preparation from Aspergillus aculeatus, under free condition was studied. A mathematical analysis of the transfructosylation reactions was carried out to estimate the dynamic and steady-state performance of an enzyme membrane reactor (EMR) and to compare the continuous production scheme with the traditional batch process realized in stirred-tank reactor (STR). Kinetic parameters were identified simultaneously from a series of progress curves obtained from STR and EMR experimental runs. Model estimates appeared to fit well to experimental observations under the studied reaction conditions. Although conventional batch reactor outperforms EMR in terms of conversion, EMR compares favorably regarding productivity. The on-site industrial implementation of this technology might be attractive for food manufacturers aiming at utilizing a value-added sweetener mixture with prebiotic properties.

Open access
Progress in Agricultural Engineering Sciences
Authors:
V. Parrag
,
Z. Gillay
,
Z. Kovács
,
A. Zitek
,
K. Böhm
,
B. Hinterstoisser
,
R. Krska
,
M. Sulyok
,
J. Felföldi
,
F. Firtha
, and
L. Baranyai

Abstract

One of the most important food safety issues is the detection of mycotoxins, the ubiquitous, natural contaminants in cereals. Hyperspectral imaging (HSI) is a new method in food science, it can be used to predict non-destructively the changes in composition and distribution of compounds. That is why, in the last decade, the potential of HSI has been evaluated in many fields of food science, including mycotoxin research.

The aim of the recent study was to test the feasibility of HSI for the differentiation according to the toxin content of cornmeal samples inoculated with Fusarium graminearum, Fusarium verticillioides and Fusarium culmorum and samples with natural levels of mycotoxins. Samples were measured in the near infrared wavelength range of 900–1,700 nm and mean spectra of selected regions of interest of each image were pre-treated using Savitzky-Golay smoothing and standard normal variate (SNV) method. On the spectra, partial least squares discriminant analysis (PLS-DA) was carried out according to the level of contamination. Partial least squares regression (PLSR) method was used to predict deoxynivalenol (DON) content of samples and the cumulative toxin content: the sum of fumonisins (FB1, FB2) and DON content of samples. Based on the promising results of the study, HSI has the potential to be used as a preliminary testing method for mycotoxin content in feed materials.

Open access

Cseresznyefák terméshozását és gyümölcsminőségét befolyásoló műtrágya kísérletek eredményei

Results of fertilizer experiments on yield and fruit quality of sweet cherry trees

Agrokémia és Talajtan
Authors:
Ádám Csihon
,
István Gonda
,
Mihály Orosz-Tóth
,
Sándorné Kincses
, and
Imre Holb

Plant nutrition significantly influences yield and fruit quality in fruit orchards. In this three-year study (2016–2018), different fertilizer treatments were compared in an intensive sweet cherry orchard. Trees of cultivar ‘Carmen’ were grafted on Prunus mahaleb ‘Cema’ rootstock, and were trained to free spindle. For NP, NPK and NPKMg treatments, yield ranged between 11.8 and 16.6 kg/tree in the three years, while the yield was 9.1 kg/tree on the control trees. Crop load (fruit amount calculated to the trunk thickness) was 151–166 g cm-2 for fertilized trees, while it was 120 g cm-2 on the untreated trees. Fruit sizes of fertilized trees reached 30 mm in 2018, while the fruit sizes of control trees were smaller with 2.5 mm. Water-soluble dry matter content (%) of the fertilized trees was lower in 2016 and 2017, but higher in 2018 compared to the control plots. In 2017 and 2018, fertilizer treatments resulted in an increase of the content of phosphorus (16–70%), potassium (4–22%) and magnesium (12–43%) in the fruits compared to control plots.

Open access

Kadmiumstressz detektálására alkalmazható in situ és destruktív mérési módszerek összehasonlító vizsgálata búzán

Comparative study of in situ and destructive measurements for indication of cadmium stress on wheat

Agrokémia és Talajtan
Authors:
Bettina Kelemen
,
Anna Füzy
,
Imre Cseresnyés
,
István Parádi
,
Ramóna Kovács
,
Kálmán Rajkai
, and
Tünde Takács

The effects of cadmium (Cd) stress and arbuscular mycorrhizal fungus (AMF) inoculation were investigated in wheat [Triticum aestivum L. cv. TC-33] under controlled conditions. The experiments aimed to reveal what stress responses belong to the different levels of Cd load in the growth medium (0; 1; 2,5 and 5 mg Cd kg- 1 substrate). To detect the effect of Cd stress, we compared plant physiological and growth indicators measured with both in situ and destructive methods. Electrical capacitance (CR) was evaluated during the experiments as a method to indicate stress responses through of Cd-induced root system changes.

During the growth period, the photosynthetic activity (Fv/Fm), the chlorophyll content index (CCI) of the leaves, and the CR of the root-soil system were monitored in situ. After harvest, the membrane stability index (MSI), the cadmium and phosphorus concentrations of the plants, the root dry mass (RDM), the shoot dry mass (SDM) and the leaf area (LA) were measured. The root colonization of AM fungi was estimated by microscopic examination. Data matrices were evaluated with principal component analysis (PCA) which had been proved to be a good statistical method to the sensitivity between measurement methods.

Taking all parameters into account in the PCA, a complete separation was found between the contaminated and non-contaminated variants along the main component PC1. The measured values of the Cd1 treatment sometimes overlapped with that of control plants, but differed from that of the Cd2 and Cd3 doses. The parameters well reflected that AMF inoculation alleviated the stress caused by Cd. PCA shows a visible effect of AM, but the separation between mycorrhizal and non-mycorrhizal plants is weaker than that between Cd contaminated and non-treated ones. The Cd stress significantly decreased the Fv/Fm, CCI, CR, SDM, RDM and LA. The CR and growth parameters proved to be the best indicators to characterize the Cd phytotoxicity in the TC-33 wheat cultivar.

Open access

MÚLT-JELEN-JÖVŐ a hazai mezőgazdasági talajvizsgálatokban

PAST-PRESENT-FUTURE in Hungarian soil analyses

Agrokémia és Talajtan
Authors:
Viktória Vona
,
István Attila Bakos
,
Zsolt Giczi
,
Renátó Kalocsai
,
Márton Vona
,
István Mihály Kulmány
, and
Csaba Centeri

The purpose of the present paper is Authors aim was to deliver a compilation of to summarize the Hungarian soil analysies methods and theas well as to present the advisory system for nutrient management advisory system. Both of them are based on several decades of work. We need to should learn from these past experiences of reasonable and good agricultural practices. We can only apply the present and future results of soil science and find out what direction should we develop, if we were aware of the results of the past and we calculate with their governing effects. The majority of our recent methods are based on historical researches and the present current statesituation of our field of scientific fieldce can only be judged and developed further if we knew the former history of the methodological findings. The recent Hungarian soil analysis system provides useful results that can be used very well today, however, the adaptation of the new international methods , learned from the follow-up of the international trends can might provide open new perspectives in for the Hungarian laboratory analyses methodology. TThe subject is extremely timely because there are hea never- met demand for cost and time effective, environmentally friendly soil analysis methods underpin how actual and hot the topic is. nowadays.

Open access

A talaj fixált ammónium-ion tartalmának hatása a talajvíz tisztulási folyamataira a szennyezőforrás felszámolását követően települési környezetben

Effects of fixed ammonium ion content of the soil on groundwater purification processes after the elimination of the pollution source in municipal environment

Agrokémia és Talajtan
Authors:
Tamás Mester
,
Daniele Cavalli
,
Dániel Balla
, and
György Szabó

Growing NH4 + content of groundwater results in increasing exchangeable and fixed ammonium ion content of the soil. NH4 + bond in the soil may go again into solution parallel with the dilution of the soil solution but at a slower rate than fixing. This process influences significantly the NH4 + content of the soil. In settlements with no sewerage system the high NH4 + content of sewage flowing out of uninsulated septic tanks may increase the fixed NH4-N content of the soil that could have a significant effect on the quality of groundwater even after the potential disappearance of pollution sources.

In this study the effects of the fixed NH4-N content of the soil around an uninsulated residential septic tank on the purification processes of the groundwater were investigated. The septic tank in the study area was dismantled in 2014 after 27 years of operation as a sewerage system was constructed. When the tank was still in operation in 2012 and 2013, very high, 55–75 mg l-1 NH4 + content was measured in the water of the monitoring well 1 metre from the tank in the course of seasonal sampling. When sewage outflow was terminated in 2014 concentrations decreased right away but even 5 years after pollutant supply was stopped, concentrations (35–57 mg l-1) highly exceeding the pollution limit (0.5 mg l-1) were measured. Considering this very high concentration, it can be assumed that great amount of NH4 + is still released into the groundwater.

In order to prove this, the exchangeable and fixed NH4-N and NO3-N contents of the soil were determined by 20 cm down to a depth of 4 metres (2019). The measurements indicated the significant accumulation of exchangeable and fixed NH4-N in the zone between 220 and 400 cm. Highest fixed NH4-N concentrations of 457 mg l-1 were found between 220 and 240 cm suggesting that sewage outflow was most intense at this depth. Slow decrease in concentrations can be observed in deeper zones but concentrations higher than 350 mg l-1 were measured between 220 and 380 cm. Based on correlation analyses, the quantity of fixed NH4-N shows no correlation with the soil texture thus it can be stated that the vertical pattern of NH4-N content is determined dominantly by sewage outflow and its depth. In the unsaturated zone of the borehole a significant accumulation of NO3-N was also identified. The maximum of NO3-N was found in the zone between 100 and 140 cm. The peak nitrate calculated for NO3 - ion with a value >1300 mg kg-1 is 2.5 times the limit set for the nitrate content of the geological medium.

Based on the results, exchangeable and fixed NH4-N contents in the soil are still very high, 5 years after sewage outflow was stopped. The continuous solution of this component still contributes to the high NH4 + content of the groundwater. As a result, the contaminated soil in the immediate environment of the septic tank is still a pollution source.

Open access

Abstract

In the last years, an alternative and convenient way to composting and/or bio-gasifying food waste is represented by the extraction of high value bioactive components from such materials. In particular, essential oils contained in matrices such as orange or lemon peels may represent high value bioactive components for the nutraceutical and pharma industry. In recent years, microwave assisted processes have been considered for use in solvent-free extraction. However, the microwave assisted extraction is often performed in very simple microwave systems, without an accurate control, if any, of the power release.

In this work, the linear tuning of microwave power for the extraction of bioactive components from citrus peels is discussed, with emphasis on the consequent process yield and extract characteristics. Chemical analysis of the extracted mixture showed the presence of quite a number of active molecules of relevant interest for pharmaceutical and nutraceutical industries, such as glycoside flavanone (Hesperidin and Eriocitrin) in lemon peels, and polymethoxylated flavones (Nobiletin and Sinensetin) in orange peels.

Open access