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Agrokémia és Talajtan
Authors:
Péter Csontos
,
Júlia Tamás
,
Zsófia Kovács
,
Judit Schellenberger
, and
Tibor Kalapos
Restricted access

“Talaj – növény holobiont komplex – a megismeréstől az alkalmazásig”•

tudományos előadóülés (on-line), 2021. szeptember 16.

Agrokémia és Talajtan
Authors:
Tibor Szili-Kovács
and
Károly Márialigeti
Restricted access
Agrokémia és Talajtan
Authors:
Zoltán Szalai
,
Noémi Ujházy
,
Melinda Megyes
,
Gergely Jakab
,
Balázs Madarász
,
Dóra Zacháry
,
Tamás Árendás
,
Zoltán Barcza
, and
Andrea Borsodi
Restricted access
Restricted access

Abstract

As the world is facing numerous global ecological issues at once, the question arises of what will help mitigate and solve contemporary matters related to resource management or climate change without devastating the economies. Fortunately, the widespread application of the circular economy would help countries worldwide simultaneously ensure economic growth without significant environmental deterioration, essentially decoupling the two factors. While Hungary’s contribution to environmental problems is not significant in absolute terms, the economic sector’s circular transition could help the country decrease its impact in relative terms and pave the path for a green economy. Nevertheless, companies, especially SMEs, tend to struggle the most with the initial phases of the shift thus it is crucial to assess the factors that prevent and support their transition.

Open access

Abstract

Potential functional food bakery products were developed and characterized based on White Lupin (Lupinus albus cv. Nelly) flour. Analytical properties of the seeds resemble to previously described Lupinus species, with significantly high protein content (45%). The high protein and dietetic fiber content of the seeds makes Lupin flour suitable to develop potential functional food products with high nutritional values. Results of the development of sweet biscuits and salty crackers enriched with Lupin flour are presented. Sensory evaluation of the bakery products was carried out by 15 panelists using the nine points hedonic scale. Heat stability of White Lupin proteins were investigated by gel-electrophoretic analysis, White Lupin proteins are quite stable at 140°C, after 35 min heating the biscuits still contain 69% of the original amount of proteins. Baking conditions were optimized also based on gel-electrophoretic experiments, the optimal baking time was 30 min at 140°C. Gluten-free Lupin-based biscuits and crackers were produced by completely omitting wheat flour from the recipes.

Open access

Abstract

Wastewater issues became a complex challenge in the world. There are several methods in wastewater treatment, such as chemical, physical, biological, and the combination of each method. However, each process has advantages and disadvantages. The physicochemical methods are common methods used in wastewater treatment, such as adsorption and coagulation. Adsorption and coagulation are excellent methods to remove pollutants. The adsorption process is greatly influenced by pH, adsorbent dose, temperature, and contact time. Coagulant dose, settling time, and pH are the main factors in the coagulation process. Chemical material as an adsorbent and coagulant has been studied in previous research, but recently, to substitution chemical materials is a challenging subject. Natural substances are potential new materials in wastewater treatment and became popular due to their efficiency and environment friendly characteristics. This review investigated the role of adsorption and coagulation in wastewater treatment and the utilization of natural materials as adsorbents and coagulants.

Open access

Abstract

Built elements and structures are a prominent component of our historic gardens, both in terms of function and artistic composition and garden scenery. The surveys of historic garden structures are important research tasks, which also underpins and validates restoration work.

In most cases, the neglected state of historic gardens and sites and the unavailable archival materials do not allow an authentic restoration of historic gardens to their original state. Nevertheless, there is a real need to reconstruct our historic gardens, based not only on historical authenticity but also on a systematic reinterpretation of the relationship between society and landscape.

The objective of this article is to present a general methodology for renewal of historic gardens through examples of specific garden reconstructions. The case studies are the authors' own design works, which demonstrate the application of different design approaches, highlighting details of the reconstruction of specific built garden elements.

Open access

Szélerózió okozta talaj-, humusz- és tápanyag-áthalmozás különbségeinek feltárása különböző szerkezeti adottságú csernozjom talajokon terepi szélcsatorna kísérletek alapján

Exploring the differences in soil, humus and nutrient accumulation caused by wind erosion on chernozem soils with different structural properties by field wind tunnel experiments

Agrokémia és Talajtan
Authors:
Andrea Farsang
,
Károly Barta
,
József Szatmári
, and
Máté Bartus

Kutatásunk során Magyarország két dél-alföldi réti csernozjom talajú területét vizsgáltuk azon céllal, hogy in situ körülmények között számszerűsítsük a különböző szélesemények által okozott talajveszteség mértékét, az ezzel együtt járó humusz- és tápanyagáthalmozás nagyságrendjét, valamint a két terület defláció érzékenységében tapasztalt különbségek okait.

Vizsgálati területeink Békés megyében, Makótól K-re mintegy 10 km-re, Apátfalva külterületén, valamint Csongrád megyében Szegedtől ÉNy-ra 2 km-re helyezkedtek el. Kutatásunk célkitűzései az alábbiak voltak: terepi szélcsatornás mérésekre alapozott laboratóriumi mérések alapján különböző szerkezeti állapotú csernozjom talajokra meghatározni

  1. az indítósebességet,
  2. a szélerózióval áthalmozott szedimentben mért makroelem, és humuszanyag feldúsulását,
  3. valamint az ezekre ható talajtani tényezőket.

A hasonló mechanikai összetételű, Szeged és Apátfalva melletti réti csernozjom talajok aggregátum összetételében, valamint a CaCO3 és humusztartalomban megfigyelhető különbségek hatására a Szeged melletti csernozjom mintaterület talaja defláció érzékenyebb. A Szegedtől É-ra eső csernozjomokon 6,5–9,0 m s–1 közötti indítósebesség értékeket mértünk, míg Apátfalván 13,0 m s–1 volt az indítósebesség értéke. Az apátfalvi terület talajának magasabb karbonát- és humusztartalma, valamint aggregátum összetételében mért magasabb morzsa arány az indítósebességérték növelésének irányába hat. A feltalajban a 0,5 mm-nél kisebb aggregátumok magasabb aránya következtében nemcsak kisebb indítósebesség értékeket, hanem nagyobb áthalmozódó talajmennyiséget, valamint ezzel együtt nagyobb mennyiségű humusz- és foszfor elmozdulást mértünk az egységesen 10-10 perces fújatási kísérleteink alkalmával a szegedi mintaterületen. Megállapítható tehát, hogy egyazon talajtípusba eső, s azonos textúrájú (homokos vályog) talajok esetében az aggregátum összetételben, valamint a CaCO3 és humusztartalomban megfigyelhető eltérések hatására jelentős különbségek tapasztalhatók a defláció érzékenység, az indítósebesség, a szediment szállítás módja és a humusz- és elemáthalmozás mértéke között.

In our research, two Chernozem soil areas were examined in the southern part of the Great Hungarian Plain in order to quantify the amount of the soil loss, humus and nutrient transport caused by different wind events and in order to show the causes of the differences in the sensitivity of deflation between the two areas.

Our study areas were located in Békés County, one of them was near Apátfalva, about 10 km east of Makó, and the other one was 2 km northeast of Szeged in Csongrád County. Our in situ wind tunnel experiments were accomplished on 2–4 June 2011 at Apátfalva and in July 2013 in Szeged. The objectives of our research were the followings:

  1. determination of the enrichment ratios for humus, macro- and microelements in the wind eroded sediments in the case of Chernozem soils with different structures based on field experiments and laboratory measurements;
  2. determination the affecting actual soil factors;
  3. estimation of soil loss and element rearrangement trends on Chernozem arable lands under different wind velocity on plot scale.

Because of the differences in the aggregate size distribution, CaCO3 and humus content, Chernozem soil near Szeged is more sensitive to deflation than near Apátfalva. Threshold friction velocity was measured between 6.5 and 9.0 m s–1 near Szeged, while the same parameter was 13.0 m s–1 at Apátfalva. The higher carbonate and humus content and the higher crumb ratio of the soil on the Apátfalva area result increasing threshold friction velocity. Due to the higher proportion of aggregates smaller than 0.5 mm in the topsoil, we have measured not only lower threshold friction velocities, but also a larger quantity of transported soil and a larger humus and phosphorus loss during the uniform 10-10 minute long wind tunnel experiments in the Szeged sample area. It can be concluded that even in spite of the same soil type and same texture there are significant differences between deflation sensitivity, threshold friction velocity, sediment transport mode, humus and nutrient transportation because of the significant differences in aggregate size distribution, CaCO3 and humus content.

It means that the agronomic structure of the soils greatly influences the mitigation and aggravation of the soil the stress effects caused by climate change. Extreme weather situations have drawn attention to the fact that improperly applied cultivation methods, tools, and overuse of Chernozem soils can modify the soil structure. One of the most serious affect is the dusting of the surface layer of the soil. During this process the larger macroaggregates disintegrate into microaggregates and the resulting smaller fractions are more exposed to wind erosion.

The dust load affecting our settlements is mainly originated from arable lands. The mitigation of this emission is fundamentally based on the regulation of land use, farming practices and deflation. “Best Management Practices” (BMPs) mean a group of selected tools that can reduce or eliminate the transport of pollutants from diffuse sources before, during and/or after agricultural activities. However, these diffuse agricultural loads caused by wind erosion can only be quantified if the magnitude and spatial movement of the dust and pollutants is monitored.

Open access