Chernozem under different agricultural land use were compared in a suburban area: three on cropland with different land use histories; one in an area of complex cultivation; one fallow; and one under grassland, considered to be in close to natural state, as a control. Soil profiles at each site were described and classified, and chemical characteristics analyzed in detail. Topsoil (0-40 cm) bulk density (BD), total organic carbon (TOC), total nitrogen (TN), ammonium lactate-extractable P, K, Ca and Mg were measured, and microbiological communities were characterized by phospholipid-fatty acid (PLFA) markers. We found significantly increased BD but decreased TOC and TN in the cultivated sites compared to the control. Values of ammonium lactate-extractable P (P-AL) were higher at the natural site, but Ca-AL, Mg-AL and K-AL content of the cultivated and mineral-fertilized agricultural sites were higher than or equal to the grassland site. Total microbiological activity correlates significantly positively with TOC and TN and negatively with the BD. Sites with perennial vegetation cover and higher biodiversity showed greater microbiological activity and, in case of the arbuscular mycorrhizal fungi, actinobacteria and anaerobe bacteria, the differences are significant. Despite the nutrient depletion and lesser microbiological activity, cropland sites preserved their taxonomic status as Chernozem. Sites that have undergone more extreme human impacts before the recent land use had lost their diagnostic features (aggregation, color, secondary carbonate accumulation) and now key out as Kastanozem, Phaeozem or Regosol.
Coffee, a widely consumed beverage, offers health benefits alongside enjoyment. While coffee chemistry has been studied for years, the existence and formation of nanoparticles in coffee remain incompletely understood. This research explores how carbon nanodots (C-CNDs) form in coffee under various conditions of brewing, including (1) bean types, (2) grind sizes, (3) the coffee-to-water ratios, and (4) brewing time and temperatures. The results show that the C-CNDs formation increased with Arabica beans, coaster grinds, and a 1:15 coffee-to-water ratio (g/g). Higher temperatures (over 90 oC) and longer brewing times also yielded more C-CNDs. Our findings revealed that the isolated C-CNDs have an average size of 3.2 +/- 0.9 nm and are characterized using fluorescence spectrophotometer, UV-Vis, and TEM techniques. We also examined fundamental coffee compositions like caffeine content, pH, total dissolved solids (TDS), and browning color, finding the correlation with C-CNDs. While C-CNDs show a strong negative correlation with caffeine content (-0.8), there is a weak negative correlation with pH (-0.33), TDS (-0.48), and browning color (-0.62). This establishes a new link between C-CNDs and caffeine content. These discoveries, backed by robust scientific methods, enhance our understanding of coffee's composition and have potential health implications.
Pleurotus ostreatus (Jacq. ex Fr.) P. Kumm mushrooms are cultivated on diverse by-products based on substrates that hold promise for mitigating antibiotic usage in the poultry industry and reducing environmental pollution. By incorporating agricultural by-products into mushroom cultivation, the functionality of the mushroom products can be increased, then the final product can be a more effective feed supplement. After mushroom cultivation, spent mushroom substrate (SMS) can be valorized, due to the presence of huge amounts of bioactive compounds like β-glucan, chitin, polyphenols, and flavonoids related to mycelia. As a prebiotic and antimicrobial feed supplement, these mushrooms positively influence gut microbiota, intestinal morphology, and thus overall poultry well-being. This article underscores the potential of solid-state fermentation (SSF) to enhance the bioactivity of oyster mushrooms and their derivatives, offering a cost-effective and efficient strategy for transforming unconventional feeding materials. Moreover, it emphasizes broader implications, including the reduction of antibiotic dependence in poultry farming, highlighting the promising integration of oyster mushrooms and their derivatives for sustainable and environmentally conscious poultry production.
Oyster mushrooms (Pleurotus ostreatus L.) are renowned for their antioxidant, antimicrobial, and prebiotic properties. This study explores the antioxidant characteristics, activity, and β-glucan content in freeze-dried mushroom samples, investigating the influence of sous-vide cooking. Uncooked freeze-dried P. ostreatus and three pre-cooked freeze-dried samples (70, 80, 90 °C through 4 hours) were analysed for Total Polyphenol Content (TPC), Total Flavonoid Content (TFC), Radical Scavenging (DPPH), Ferric Reducing Antioxidant Power (FRAP), and β-glucans content via HPLC and Total Dietary Fiber (TDF) via enzymatic gravimetric method. Results indicate that uncooked mushroom powder exhibited superior antioxidant capabilities compared to cooked samples. The sous-vide cooked (80 °C) mushrooms displayed the highest total phenolic and flavonoid content. Moreover, pre-cooked (70 °C) mushroom powder demonstrated the highest β-glucan content, significantly surpassing the uncooked control sample. Notably, pre-cooked groups (80, 90 °C) demonstrated significantly higher TDF levels compared to uncooked sample. This research offers valuable insights into the potential use of mushrooms as high-antioxidant, antimicrobial, and prebiotic food or feed supplements, with broad implications across various fields.
This study aimed to examine the impact of mushroom extract-based solid media on the β-glucan content, growth rate, density, and biomass content of Pleurotus ostreatus (oyster mushroom) mycelia. Fresh, high-quality raw P. ostreatus were washed, sliced, and heated in a sealed pressure cooker at 90°C for 4 h in the drying cabinet. Following the heating process, centrifugation was carried out. Different concentrations of Pleurotus ostreatus extract were mixed with distilled water (0%, 25%, 50%, 75%, and 100%) and prepared for a sterile solid media. A malt extract-based medium was maintained as a control. This study focuses on the growth performance of P. ostreatus mycelium on its own mushroom extract-based culture medium which holds considerable economic and environmental significance. During the six-day observation period, the mycelium exhibited consistent growth across all tested media, maintaining a steady growth rate of 15 mm. The increased content of mushroom extract resulted from the enhanced density of the mycelia and biomass content. It can be inferred that when media containing less than 25% of mushroom extract dilution is used, β-glucan can be formed in smaller amounts. Further research is needed to explore mushroom extract derived from different types of mushroom byproducts, which fail to meet commercial standards.
The effects of intensive and reduced tillage, fertilization, and irrigation on soil chemical and microbiological parameters were studied in a long-term field experiment in Hungary. The treatments were plowing tillage, ripper tillage, strip tillage; control (without fertilization), NPK fertilization (N: 160 kg/ha; P: 26 kg/ha; K: 74 kg/ha); and non-irrigation and irrigation. Soil samples were collected through maize monoculture in the fall of 2021 in the 30th year of the experiment. The soil organic carbon, total nitrogen, soil microbial biomass (based on PLFA analysis), and soil enzyme activity were observed to be significantly high in the strip tillage plots, but were lower in the ripper tillage plots, and even lower in the plowing tillage plots. The fungal, arbuscular mycorrhiza fungal, and bacterial biomasses were significantly higher in the strip tillage and ripper tillage plots compared to the plowing tillage plots. The strip tillage treatment was found to be the most favorable cultivation method for improving the microbial biomass and activity of Chernozem soil, followed by the ripper tillage and plowing tillage treatments. The long-term use of chemical fertilizers greatly reduced the soil microbial biomass and negatively impacted the soil microbial community, leading to a decrease in fungi and Gram-negative bacteria. The ratio of cyclopropyl PLFA precursors to cyclopropyl PLFAs, as a “stress factor”, indicated the most stressful bacterial environment was that found in the fertilized, non-irrigated plowed soil.
Pleurotus ostreatus (oyster mushroom) holds excellent promise worldwide, bringing several opportunities and augmenting the tool sets used in the biotechnology field, the food industry, and medicine. Our study explores the antimicrobial and probiotic growth stimulation benefits of freeze-dried P. ostreatus powders (OMP-TF, oyster mushroom powder from the total fresh sample; OMP-CSR, oyster mushroom powder from the cooked solid residue; OMP-CL, oyster mushroom powder from the cooked liquid), focusing on their bioactive compounds and associated activities. Our research examined polysaccharide fractions—specifically total glucans and α- and β-glucans—alongside secondary metabolites, including polyphenols and flavonoids, from freeze-dried mushroom powders. Additionally, carbon nanodots (CNDs) were also characterized. The growth inhibition was tested against Escherichia coli and Staphylococcus epidermidis, while the capacity for stimulating probiotic growth was evaluated using Lactobacillus plantarum and Lactobacillus casei. Evidence indicates that OMP-CL and OMP-CSR exhibit significant antimicrobial properties against S. epidermidis Gram-positive bacteria. OMP-CL notably promoted the growth of L. casei. OMP-CL, containing the most significant number of CNDs, has shown to be a valuable source for gut microbiota modulation, with its antimicrobial and probiotic-stimulating efficacy. However, further in vitro and in vivo studies should be performed to explore CNDs and their behavior in different biological systems.
Baked pretzels are a popular choice for a quick snack, easily identifiable by their classic twisted shape, glossy exterior, and small salt crystals sprinkled on top, making them a standout snack. However, it is not commonly known that compounds with fluorescent properties can be formed during their production. Carbon nanodots (CNDs) with an average size of 3.5 nm were isolated and identified in bakery products. This study delved into the formation of CNDs in pretzel production using a fractional factorial experimental design. The research revealed that the baking temperature had the most significant impact on the concentration of CNDs, followed by the concentration of NaOH in the immersion solution, and then the baking time. This study highlights the unique role of the NaOH immersion step, which is not typically present in bread-making processes, in facilitating the formation of CNDs. This discovery highlights the strong correlation between the formation of CNDs and the heat treatment process. Monitoring and controlling these factors is crucial for regulating the concentration of CNDs in pretzel production and understanding nanoparticle formation in processed foods for food safety.
The combined effects of increasing sulfur (S) fertilization rates and drought stress on the yield and compositional parameters of spring wheat on Chernozem soil were studied. In a greenhouse pot experiment, increasing S doses (22.4, 28, 56 kg S/ha) were used with a constant nitrogen (N) dose (112 kg N/ha), resulting in different N:S ratios (1:0.2; 1:0.25; 1:0.5). Water supply treatments included optimal irrigation, maintaining 60% of field capacity, and a water stress treatment where irrigation was withheld until wilting symptoms appeared, followed by irrigation to 40% of field capacity. By measuring the dry biomass production; plant N and S%; and inorganic sulfate-S content, the N/S ratio; harvest index (HI); and organic S, N and S uptake were determined. Our findings indicate that, under water stress, S incorporation into plants is limited, as it tends to remain in an inorganic form. Furthermore, results showed an increase in the N/S ratio under drought conditions, suggesting that drought stress impedes S uptake more significantly than N uptake. In this experiment, fertilization with 112 kg N/ha and 56 kg S/ha (N:S = 1:0.5) proved to be most effective under adequate water supply. In this treatment, grain N and S% were 1.80% and 0.18%, respectively.
Plant-based foods offer a sustainable alternative to meet the growing protein demand. Legumes are the most promising of these, as they contain relatively high concentrations of protein, low digestible starch, and dietary fiber, as well as them possibly featuring low levels of fat. Enzymatically modified legume proteins provide us with tempting perspectives in terms of enhancing foods’ biological values. However, their bioavailability and digestibility are generally less sufficient than that of proteins of animal origin, which may be improved by well-tailored enzyme modification. In this study, the efficacy of three plant-based proteases (bromelain, ficin, and papain) were evaluated at two distinct concentrations (2.5% and 10%) and three hydrolysis durations (1, 2, and 12 h) when transforming chickpea and lentil proteins. The degree of hydrolysis (DH), peptide profiles, and free amino acid content were analyzed to determine the efficiency of each enzyme. Results showed significant variations in DH, which was influenced by enzyme type, concentration, and hydrolysis duration. Papain exhibited the highest DH, particularly at a 10% concentration, reaching 27.8% efficiency in chickpea and 34.8% in lentils after 12 h. Bromelain and ficin were proven to be less effective, with ficin showing the least hydrolytic activity. SDS-PAGE analysis revealed substantial protein degradation, especially subsequent to papain treatment, pointing out that most proteins were cleaved into smaller peptides. SEC-HPLC indicated a predominant release of peptides within the 200–1000 Da range, suggesting enhanced bioavailability. Papain and bromelain treatments resulted in a significant release of oligopeptides and dipeptides. UHPLC analysis highlighted a marked post-hydrolysis increase in total free amino acids, with arginine, leucine, and lysine being the most abundant ones. Notably, tryptophan, being undetectable in untreated samples, was released in measurable amounts post-hydrolysis. These findings demonstrate papain’s superior performance in protein hydrolysis and its potential in producing bioactive peptides, highlighting its applicability in food processing and the development of both nutraceuticals and functional foods.
Carbon nanodots (CNDs) are a class of nanoparticles with unique optical properties with broad applications in various fields. However, synthesizing CNDs with high fluorescence intensity and small size using a green solvent and low temperature remains challenging. In this study, we investigated the use of the Maillard reaction for synthesizing CNDs and optimized the reaction conditions at 120 degrees C for 12 h to achieve CNDs with desirable properties. The results showed that glycine was the most effective amino acid for CNDs formation when combined with sucrose. A molar ratio of 1 : 1 for glycine : sucrose resulted in the highest fluorescence intensity. The fluorescence intensity increased remarkably with 40% ethanol as the extraction solvent. However, a high ethanol concentration (above 60%) had an inverse relationship with CNDs' fluorescence intensity, indicating that a high concentration of ethanol solution prevented the Schiff base formation. The purified CNDs (M-CNDs) were characterized using fluorescence spectrophotometry, UV-Vis spectroscopy, Raman spectroscopy, and TEM techniques. These findings provide a purification process of sustainable CNDs using the Maillard reaction and green solvents with optimized conditions and low temperatures. Developed method to optimize green CNDs synthesis & measure concentration in baked goods. Extracted CNDs characterized using TEM, Raman, UV-Vis & fluorescence.
To provide insight into the patterns of soil organic matter decomposition, changes in the quantity of biopolymers and the correlation between them were followed using 2D correlation spectroscopy (2DCOS) FTIR. Soil organic matter fractions with different vegetation/land use (grass, spruce, oak and arable) were examined in a 1-year laboratory incubation. The non-protected organic matter fraction was calculated in terms of particulate organic matter (POM), the carbon stabilized in aggregates as S + A (sand + aggregates), and the mineral-associated organic matter (MAOM) as the s + c (silt and clay) fraction. Forest soils (spruce, oak) exhibited high C and N accumulation in the POM fraction (48, 43
Strawberry production presents special challenges due the plants’ shallow roots. The rooting stage of strawberry is a crucial period in the production of this important crop. Several amendments have been applied to support the growth and production of strawberry, particularly fertilizers, to overcome rooting problems. Therefore, the current investigation was carried out to evaluate the application of biological nanofertilizers in promoting strawberry rooting. The treatments included applying two different nanofertilizers produced biologically, nano-selenium (i.e., 25, 50, 75, and 100 mg L−1) and nano-copper (i.e., 50 and 100 mg L−1), plus a control (untreated seedlings). The rooting of strawberry seedlings was investigated by measuring the vegetative growth parameters (root weight, seedling weight, seedling length, and number of leaves), plant enzymatic antioxidants (catalase, peroxidase, and polyphenol oxidase activity), and chlorophyll content and its fluorescence and by evaluating the nutritional status (content of nutrients in the fruit and their uptake). The results showed that the applied nanofertilizers improved the growth, photosynthetic pigments, antioxidant content, and nutritional status of the seedlings compared to the control. A high significant increase in nutrient contents reached to more than 14-fold, 6-fold, 5-folf, and 4-fold for Cu, Mn, N, and Se contents, respectively, due to the applied nanofertilizers compared with the control. The result was related to the biological roles of both Se and CuO in activating the many plant enzymes. Comparing the Se with the CuO nanofertilizer, Cu had the strongest effect, which was shown in the higher values in all studied properties. This study showed that nanofertilizers are useful to stimulate strawberry seedling growth and most likely would also be beneficial for other horticultural crops. In general, the applied 100 ppm of biological nano-Se or nano-CuO might achieve the best growth of strawberry seedlings under growth conditions in greenhouses compared to the control. Along with the economic dimension, the ecological dimension of biological nanofertilizers still needs more investigation.
The various climate scenarios consistently predict warming and drying of forests in Hungary. Soils play a significant role in the long-term sequestration of atmospheric CO2, while in other cases they can also become net carbon emitters. Therefore, it is important to know what can be expected regarding future changes in the carbon storage capacity of soils in forests. We used precipitation gradient studies to solve this problem, using a type of “space–time” substitution. In this research, we primarily examined the quality parameters of soil organic matter (SOM) to investigate how climate change transforms the ratio of the main SOM compound groups in soils. For our studies, we applied elemental and 13C and 15N isotopic ratio analysis, NMR analysis, FT-IR spectra analysis, thermogravimetric and differential thermal analyses to measure SOM chemistry in samples from different oak forests with contrasting mean annual precipitation from Central Europe. Our results showed that soil organic carbon (SOC) was lower in soils of humid forests due to the enhanced decomposition processes and the leaching of Ca, which stabilizes SOM; however, in particular, the amount of easily degradable SOM compounds (e.g., thermolabile SOM, O-alkyl carbon, carboxylic and carbonyl carbon) decreased. In dry forest soils, the amount of recalcitrant SOM (e.g., thermostable SOM, alkyl carbon, aromatic and phenolic carbon and organo–mineral complexes stabilized by Ca increased, but the amount of easily degradable SOM increased further. The main conclusion of our study is that SOC can increase in forests that become drier, compensating somewhat for the decrease in forest plant biomass.
Carbon in soil is one of the most important indicators of soil fertility. Part of the carbon stored in them is returned to the atmosphere during soil respiration. Climate change and inappropriate land use can accelerate these processes. Our work aimed to determine how soil CO2 emissions change over ten years as a result of litter manipulation treatments. Plots at the Síkfőkút DIRT (Detritus Input and Removal Treatments) experimental site include doubling either leaf litter or wood, and removing all aboveground litter, all root inputs, or removing all litter inputs. With the help of this, we were able to examine not only the effects of the different organic matter intake but also the effects of the different microclimates that occur as a result of the treatments. Total soil respiration (root and microbial respiration) is a result of a persistent lack or excess of soil organic matter relative to soil moisture. Based on our studies, the increase in the intensity of root respiration on wetter soils was only half of the increase in respiration associated with decomposition activity. The sustained growth of leaf litter significantly increases soil respiration, which can be partly explained by the more favorable supply of nutrients to the decomposing organisms, and partly by the more favorable microclimatic conditions, however, these effects were only valid in the case of wetter soils. In the dry summer environment, we experienced higher CO2 emissions during litter removal treatments. In the first period between 2002 and 2004, even wetter root removal treatments showed a significantly higher CO2 emission, while in the period 2010–2012, surface litter removal treatments. The permanent removal of surface litter in the drier summer period resulted in the formation of a dense crack network, which increased the CO2 emission of these soils, which increases the soil organic carbon loss of the soil. Our study proves the advantages of mulching in terms of a more favorable microclimate of the soil surface and a balanced carbon balance of the soil–plant system.
Using seleno-compounds and telluric compounds is a practical approach for developing solutions against drug-resistant bacterial infections and malignancies. It will accelerate the search for novel treatments or adjuvants for existing therapies. Selenium and tellurium nanospheres can be produced by lactic acid bacteria. The bacteria can differentiate the selenium and tellurium when the medium contains both selenite and tellurite. Therefore, our question in this study was the following: are they making alloys from the selenium and tellurium and what will be the composition, color, and shape of the nanoparticles? We used a simple microbial synthesis to produce nanoselenium, nanotellurium, and their alloys from sodium selenite and sodium tellurite using Lactobacillus casei. This bacterium produced red spherical amorphous elemental selenium nanospheres with a diameter of 206 ± 33 nm from selenite and amorphous black nanorods with a length of 176 ± 32 nm and a cross-section of 62 ± 13 nm from tellurite. If the initial medium contains a mixture of selenite and tellurite, the resulting nanoparticles will contain selenium and tellurium in the same ratios in the alloy as in the medium. This proves that Lactobacillus casei cannot distinguish between selenite and tellurite. The shape of the nanoparticles varies from spherical to rod-shaped, depending on the ratio of selenium and tellurium. The color of nanomaterials ranges from red to black, depending on the percentage of selenium and tellurium. These nanomaterials could be good candidates in the pharmaceutical industry due to their antipathogenic and anticarcinogenic properties.
ABSTRACT This comparative investigation aimed to evaluate controlling factors for the changes of chemical and microbial properties in soils taken from chemical fertilizer experiments carried out mainly in Chernozem and Andosol in Hungary and Japan, respectively. The plant available nutrient content of the soil, the stock of C and N and the soil microbial parameters of the carbon and nitrogen cycles were examined under different land-use and vegetation. In the Japanese soils, there was about 2–3 times higher organic C content than in Hungarian soils. The average CO2-production was about 1.5 times higher in Hungary soils than Japanese soils, and significantly increased (9–37%) in the fertilized treatments compared to control in all Hungarian long-term experiments. Regarding the Hungarian soils, the NPK-fertilization especially increased the nitrate and phosphorus content of soils, among the microbial parameters of the CO2-production, MBC, MBN, net nitrification, saccharase and urease activities – in most cases significantly increased – among the six microbial examined parameters. With reference to Japanese soils, the nitrogen fertilization especially increased the nitrate and phosphorus content of soils and had the highest effect on the microbiological parameters in the forest soil, where the MBC, MBN, net nitrification, saccharase and urease activities increased significantly. Only the net nitrification increased significantly in the fertilized treatments in the all Numata experiments, and generally 10–100 times higher values were found in the Japanese soils than in the Hungarian ones. The microbial activity decreased according to land use in the following order: maize>forest>grassland in Hungary soils, and forest>grassland>apple orchards in Japanese soils. These results confirm that climate conditions and human activity have important impacts on the C and N cycles of the soil–plant–atmosphere system. Based on our results, it appears that land-use and chemical fertilization resulted in a larger change in the stock of organic matter and soil microbiological processes in the Hungarian long-term experiments compared to the Japanese experiments.
Soil organic matter content is a main driver of soil functions and ecosystem services. Various quantity of litter inputs was studied in a Quercetum-petraeae-cerris forest in northeastern Hungary at the Sikfokut DIRT (Detritus Input and Removal Treatment) experimental site. The goal of the project was to assess how rates and sources of plant litter inputs might control the accumulation and dynamics of organic matter and nutrients in forest soils over decadal time scales. Six treatments were applied at the experimental site. Beside the control (CO) condition, two detritus addition (double litter (DL) and double wood (DW)) and three detritus removal (no litter (NL), no roots (NR) and no input (NI) treatments were applied in which detritus quantities were manipulated above and below ground. Our aim was the study of the relationship between the litter treatments, their carbon (C) content and the number of microorganisms and biomass of fungi. Litter treatments also had a significant effect on soil microorganisms and soil organic carbon (SOC) content. These effects decreased in parallel with soil depth. Fungal biomass values were more than five times higher for DL (2 mg fungi g(-1) soil) than for the soils of NI (0.4 mg fungi g(-1) soil) condition in the upper 5 cm layer, while 0.57 (DL) and 0.08 (NI) values were measured in the 15-25 cm layer. The most probable number (MPN) method, which measures the number of certain groups of living and active microorganisms (fungi and bacteria), showed even greater differences between the treatments. Positive direct and indirect effects of greater organic matter inputs is affected the soil functioning through on better moisture and C content in soils. Litter entering the forest floor resulted in a larger amount of organic substrate and inorganic nutrients. In addition, it resulted in more favorable microclimatic conditions (lower temperature and soil moisture fluctuation) in the soils, which increased the number of microorganisms and the biomass of fungi. There is no significant difference in the number of microbes between the control and doubling treatments (DL, DW). Furthermore, in the case of fungal biomass, there is a significant difference only in the upper 5 cm layer of the DL. These results explain the significantly higher SOC content of the DL treatment compared to the other treatments, suggesting a weaker priming effect. In summary, the results of our research suggest that litter removal had a much greater effect on soil microbial number and fungal biomass as well as SOC content than the addition of a similar amount of litter.
A talajok a szárazföldi széntároló rendszerek egyik legjelentősebb tagját jelentik, melyek szénelnyelése, illetve szénkibocsátása jelentős mértékben hat a klímára, ugyanakkor a klímaváltozás is befolyásolja a talajok szénraktározó képességét. Az avar produkció mennyiségi és minőségi változásai jelentősen befolyásolják ezeket a folyamatokat, azonban ezek mértéke, sőt időnként iránya sem ismert pontosan.A klímaváltozás mellett a területhasználat változások is befolyásolják a talajba kerülő szerves anyagok mennyiségét és ezen keresztül számos egyéb talajfizikai, kémiai és biológiai paramétert. Ezeknek a hatásoknak a rendszerszintű vizsgálatát segítik a nemzetközi avarmanipulációs projektek, melyek azonos kezeléseket alkalmazva, de eltérő klímaviszonyok mellett vizsgálják a mesterségesen átalakított avar inputok hatását a talajrendszerekre. A Síkfőkút project területén, mely 2000-ben csatlakozott a nemzetközi DIRT projecthez, vizsgáltuk az avar input növekedésének és csökkenésének hatásait egy cseres tölgyes erdőben a talajok szén körforgalmára, illetve a vízháztartására. Ezeken a kutatásokon belül vizsgáltuk a kezelések talajaiban a talajnedvesség tartalmat, vízkapacitást és térfogatsűrűséget, valamint CNS analizátorral a talajok szerves szén tartalmát.Eredményeink azt mutatták, hogy az avar produkció mennyiségi változása, éghajlati viszonyoktól függően, eltérően hat a talajok SOC tartalmának változásaira. A kezelésekkel modellezett avar produkció változások nemcsak közvetlen úton hatnak a talajok szerves anyag tartalmára, de közvetett módon a megváltozott mikroklimatikus viszonyok révén is befolyásolják a talajok szén és vízforgalmi viszonyait. A nagyobb avar produkció a szárazabb síkfőkúti erdőben növelte a talajok szén tartalmát (szemben a nedvesebb amerikai területeken tapasztalt visszaeséssel, vagy stagnálással) és magasabb szerves anyag tartalom társulva a vastagabb avartakaróval magasabb átlagos talajnedvességet és vízmegtartó képességet eredményezett az avar elvonásos kezelésekkel szemben. Ezek a hatások összefüggésben lehetnek azzal is, hogy az avarelvonásos kezeléseknél szignifikánsan magasabb térfogattömeg értékeket mértünk, ami a pórustérfogat csökkenését jelentheti ebben az esetben, csökkentve ezzel a talajban tárolható víz mennyiségét.Az általunk végzett avarmanipulációs kísérletek nemzetközi kontextusában közelebb juthattunk a biogeokémiai ciklusok, ezáltal a mineralizáció és a humifikáció közötti összefüggések megértéséhez különböző erdőtípusokban és különböző klimatikus feltételek között.
We managed to create a self-developed sensor system, which is based on the simultaneous reflectance measurements at a 660 and 940 nm wavelength. The ratio of the reflectance refers to the concentration of the soil organic carbon (SOC). This instrument has a calibration range of 1.19 to 6.05 SOC%. The SOC content of twenty-six soil samples was measured by the self-developed system and a standard spectrophotometric method and we found that the SOC estimation in the self-developed system had a good approximation and the differences ranged from –27.72% ~ + 6.99%. We found a strong correlation between the data of the reference measurements (R2 = 0.73) and the values indicated by our self-developed sensor system (Reference (SOX%) =1.4857 × E (SOC%) – 0.7393). This measurement system is easy to use and displays and records the data in real time. This allows one to map an agricultural production area based on the SOC concentration using its built-in GPS unit.