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Progress in Agricultural Engineering Sciences
Authors: N. Anter, M. Y. Guida, M. Kasbaji, A. Chennani, A. Medaghri-Alaoui, E. M. Rakib, and A. Hannioui

Abstract

In this scientific paper, thermochemical conversion of redwood (RW) was studied. Using the thermogravimetric analysis' technique (TGA), the thermal behavior of RW samples was examined at four heating rates ranging from 5 to 20 K min−1 in inert atmosphere between 300 and 900 K. Two main objectives have been set for this study; the first one was the determination of the kinetic decomposition parameters of RW (Pinus sylvestris L.), and the second one was the study of the variation of characteristic parameters from the TG-DTG curves of the main RW's components, such as; cellulose, hemicellulose and lignin. The kinetic analysis was performed using three isoconversional methods (Vyazovkin (VYA), Friedman (FR) and Flynn-Wall-Ozawa (FWO)), Avrami theory method and the Integral master-plots (Z(x)/Z(0.5)) method to estimate activation energy (E a), reaction order (n), pre-exponential factor (A) and model kinetic (f(x)) for the thermal decomposition of cellulose, hemicellulose and lignin components.

The DTG and TG curves showed that three stages identify the thermal decomposition of RW, the first stage corresponds to the decomposition of hemicellulose and the second stage corresponds to the cellulose, while the third stage corresponds to the lignin's decomposition. For the range of conversion degree (x) investigated (0.1 ≤ x ≤ 0.7), the mean values of apparent activation energies for RW biomass were 127.60–130.65 KJ mol−1, 173.74–176.48 KJ mol−1 and 197.21–200.36 KJ mol−1 for hemicellulose, cellulose and lignin, respectively. Through varied temperatures from 550 to 600 K for hemicellulose, from 600 to 650 K for cellulose and from 750 to 800 K for lignin, the corresponding mean values of reaction order (n) were 0.200 for hemicellulose, 0.209 for cellulose and 0.047 for lignin. The pre-exponential factor's average values for three components of RW ranges from 0.08 × 1012 s−1 to 2.5 × 1012 s−1 (A hemicellulose = 1.09 × 1012 s−1), 0.10 × 1014 s−1 to 0.28 × 1014 s−1 (A cellulose = 0.17 × 1014 s−1) and 3.07 × 1016 s−1 to 3.69 × 1016 s−1 (A lignin = 3.33 × 1016 s−1), respectively. The experimental data of RW had overlapped the D 4, D 2 and F 3 in the conversion degree of 10–30%, 30–55% and 55–70% for the three components, respectively.

Restricted access

Abstract

To overcome the problems of seasonality and geographical location in fruit production and processing, the production of aseptic semi-finished juice is an excellent solution. Even without refrigeration, aseptic pressing has a shelf life of more than a year, making it possible to produce finished products all year round. The production technology involves the addition of ascorbic acid to the pulp to fix or preserve colour. There is an increasing customer demand for ascorbic acid substitutes on the international market. In Hungary, one of the most important exports is aseptic sour cherry juice. In our work, ascorbic acid used for colour fixation was replaced by acerola concentrate. The anthocyanin content and colour coordinate values (L*, a*, b*, H, C) of aseptically filled sour cherry juice were determined and compared with the control sample during the 12 months of storage.

Open access

As a means of assisting the selection of promising soil classification systems, a set of criteria were presented and tested. Inside the studied slightly saline plot World Reference Base (WRB) and Hungarian soil classification (HU) were compared at all four levels in terms of class separability, correlation to biomass, parsimony and homogeneity of classes. WRB surpassed HU in terms of the very important homogeneity of classes only, but HU performed better in terms of class separability, correlation to biomass and parsimony of classes. With many possible classification units WRB categorized the soil into a large number of classes, but 67% and 78% of them were single-profile classes at levels 3 and 4, respectively inside the ca 0.9 km2 area.

Open access

Szarvasmarhatartó telepen alkalmazott ivarzásindukáló hormonok megjelenése a hígtrágyában

Appearance of on-farm bovine reproductive hormones in the resulting slurry

Agrokémia és Talajtan
Authors: Eduárd Gubó, Tibor Molnár, Pál Szakál, Dóra Pordán-Háber, Ákos Bede-Fazekas, and Judit Plutzer

A review of the international literature also found that the amount and the presence in slurry of oestrus inducer hormone preparations used in intensive dairy cattle production has not been investigated. In our study, we followed the path of 5 different sex-inducing drugs (alfaglandin, PGF, dinolytic, gonavet, ovarelin) including three active pharmaceutical ingredients (D-Phe6-Gonadorelin, Kloprostenol and Dinoprost-tromethamine) used in a cattle farm in Pest County from their use until their appearance in the slurry from 2017 to 2020. The study included a review of drug consumption and a seasonal analysis of the hormonal effects of slurry produced on the farm in quarterly cycles each year. We also tested separately the hormonal effects of the hormone preparations used on the farm. For the estrogenic effect tests, the yeast test with the human estrogenic receptor was used according to ISO 19040. Statistical evaluation of the results (Pearson correlation and Principal Component Analysis) was used to identify relationships between the use of sex inducers, the reproductive biology of the colony and the estrogenic effect of the slurry. We found that the estrogenic effects of slurry and sludge are strongly correlated. All three pharmaceuticals tested showed a strong correlation with the estrogenic effect of slurry/sludge. Our investigations confirm that slurry among other reasons due to its hormone and drug content shall be considered as a material that needs to be disposed of by new treatment methods before application to the field, because of its environmental and health risks.

Open access

Cover crops serve as an essential source of nutrients in the soil and generally improve the soil’s properties. Cover crops’ production is considered a benefit of the soil quality; by protecting the soil from erosion, reducing the weeds and the so-called soil-borne plant pathogens. Different varieties of cover crops can be cultivated such as legumes, non-legumes, brassica, and grass-type of plants with a variability of the symbiosis. A pot experiment was carried out with five cover crops, as non-symbiont (Brassica carinata B.c.), single-symbiont with arbuscular mycorrhiza fungi (AMF) (Phacelia tanacetifolia P.t., Avena strigosa A.s.) and double symbiont with AMF and nitrogen-fixing bacteria (Vicia benghalensis V.b., Vicia faba V.f.) crops; and a mixture of the five species, placed in sandy soil (arenosol) in plastic pots (5000 g soil) in 4 repetitions. One of the pots with mixed cover crops was inoculated by AM fungi industrial product. We measured soil biological activity of dehydrogenase (DHA) and fluorescein-diacetate (FDA) enzymes, the frequency of AM fungi (F%), the all protein, glomalin content and electrical conductivity (EC) of the soils. Mixture of all the cover crops resulted maximum EC and significantly enhanced the enzymatic, DHA, FDA activities in comparison with single plants. Mycorrhiza colonization frequency was high in all cover crops except the mustard (B.c.), as nonsymbiont. Vetch (V.b.), as double symbiont was responding very positively to AMF inoculation, and enhanced the performance of its growth. It was found in the pot experiment, that vetch, has the highest capacity to retain soil-protein, glomalin concentration, as well. The mixture of five cover crops could be suggested to use, due to the synergistic positive performance of the individual crops, and the better functioning of beneficial fungal / bacterial symbiosis.

Open access
Agrokémia és Talajtan
Authors: László Simon, Marianna Makádi, Zsuzsanna Uri, Szabolcs Vigh, Katalin Irinyiné-Oláh, György Vincze, and Csilla Tóth

Open-field small plot long-term experiment was set up during 2011 with willow (Salix triandra × S. viminalis ‘Inger’), grown as a short rotation coppice energy crop in Nyíregyháza, Hungary. The sandy loam Cambisol with neutral pH was treated three times (2011, 2013, and 2016) with 15 t ha–1 municipal sewage sludge compost (MSSC) and with 600 kg ha–1 (2011, 2013) or 300 kg ha–1 (2016) wood ash (WA). In 2018 the MSSC-treated plots were amended with 7.5 t ha–1 municipal sewage sediment (MSS), and 300 kg ha–1 WA. MSSC and WA or MSS and WA were also applied to the soil in combinations during all treatments. Control plots remained untreated since 2011. Repeated application of wastewater solids (MSSC, MSS) and wood ash (WA) significantly enhanced the amounts of As (up to +287%), Ba, Cd (up to +192%), Cu, Mn, Pb, and Zn in the topsoil of willows. The combined application of MSSC+MSS+WA resulted in significantly higher Mn and Zn and lower As Ba, Cd Cr, and Pb concentrations in topsoil than MSSC+MSS treatment of soil without WA. Nitrogen concentrations in leaves of treated plants were generally slightly lower or similar to control. All soil treatments significantly enhanced the uptake or accumulation of nutrient elements (Ca, K, Mg, P) and potentially toxic elements (As, Ba, Cd, Cr, Cu, Mn, Ni, Pb, and Zn) in the leaves of willows during 2018, 2019, and 2020. Significantly higher Mn or Zn concentrations were measured in MSSC+MSS+WA than in MSSC+MSS treatments. Significant amounts of Cd (up to 1.11 mg kg–1) or Zn (up to 183 mg kg–1) can be translocated (phytoextracted) from a soil amended with wastewater solids or wood ash to willow leaves. In 2018 the treatments decreased the chlorophyll fluorescence values, while in 2019 and 2020 the light adapted fluorescence yield (Y) values were higher in treated than in control plants.

Open access

In this study PTEs, [potentially toxic elements (Cr, Cu, Mn, Ni, Pb, and Zn)] were investigated in the upper layer of floodplain soils that occurred as a result of accident in the area of two mine tailings in Northwestern Romania. A large amount of sediment was deposited on the soil of floodplains along the Hungarian section of River Tisza, which could represent a threat to the environment. Floodplain soil samples were collected from four locations in Hungary from an area of the river stretching to about 250 km. BCR (Bureau Communautaire de Référence) sequential extraction method was used to analyze both post-flood and present samples. Most of the analyzed elements (Cd, Cr, Cu, Ni, Pb, Zn) were found in the residual fraction, but there is a notable soluble amount in hydroxylammonium chloride extractable fraction. The results allow a comparison of the changes that have taken place over time, in addition to serving as a basis for further studies.

Open access
Agrokémia és Talajtan
Authors: Norbert Túri, János Körösparti, Balázs Kajári, György Kerezsi, Mohammed Zain, János Rakonczai, and Csaba Bozán

Due to extreme meteorological and soil hydrological situations the agricultural production security is highly unpredictable. To release the extent and duration of inland excess water (IEW) inundations or two-phase soil conditions during the period intended for cultivation, subsurface drainage (SD) has been used as a best practice in several countries. SD interventions took place between 1960’s and 1990 in Hungary. After 1989, land ownership conditions changed, thus professional operation and the necessary maintenance of the SD networks designed as a complex system became insignificant. In this paper, our aim was to present the IEW hazard in one of the most equipped areas by SD in Hungary. The occurrence frequency of IEW inundations in drained and non-drained (control) areas in different time intervals were compared. According to our results, we could state that the frequency of IEW on the subsurface drained areas was moderately lower in only a few periods compared to the control areas. IEW hazard of the arable areas at the Körös Interfluve was classified as nonhazarded in 52.7% of the area. Another 38.2% were moderately hazarded, 8.26% of the lands were meanly hazarded and less than 1% were highly hazarded area by IEW.

Open access

The Westsik’s long-term crop rotation experiment was set up in 1929 at the Nyíregyháza Experimental Station (NE Hungary) on a slightly acidic Arenosol. Besides fallow crop rotation (CR), effects of different organic amendments (lupine as green manure, lupine as main crop, straw manure, and farmyard manure (FYM) were studied with or without N or NPK-fertilizers. The crop rotation consisted of rye, potato, lupine, and oat with common vetch. The soil of potato plots was analysed in 2019 at the 90th anniversary of Westsik’s crop rotation experiment.

The following chemical and microbiological soil parameters were determined: soil pH, available nutrient contents, organic carbon (OC) and nitrogen (ON) contents, microbial biomass carbon (MBC) and nitrogen (MBN), soil respiration, net nitrification, and activity of some soil enzymes.

In the CRs, the soil pHH2O varied from acidic to weakly alkaline and it largely differed from pHKCl. The results showed a significant increase in the content of nitrate, available phosphorus and potassium in most of the fertilized plots. Applying straw, green manure, or FYM significantly increased the OC and ON contents. The total count of cultivable bacteria increased upon the application of the organic manures. Combined application of straw manure and N-fertilization heavily improved the abundance of the microscopic fungi.

While all the applied organic manures significantly enhanced the MBC, the MBN increased only by the green manure amendment. Our results revealed higher soil respiration rate in the plots receiving straw or FYM than in the control. Both green manure and FYM elevated the net nitrification rate. Phosphatase, saccharase, urease, and dehydrogenase enzymes showed a hesitating response to the manure application in the different CRs.

The soil respiration and dehydrogenase activity correlated to most of the measured chemical parameters. Among microbiological properties, the MBC and MBN, as well as dehydrogenase and other enzyme activities displayed a positive correlation. Results proved the need for the exogenous application of organic matter in the form of organic manures to enhance the nutritional status and health of the soil.

Open access