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Conservation tillage (CT) is a ploughless tillage with a reduced number of operations, and its positive effect on soil functions and health is widely known. Multivariate analyses are required to choose indicators that adequately characterize the changes in soil health. However, there is little research on the comprehensive analysis of the full spectrum of soil physical, chemical and biological properties. Therefore, we examined 21 soil parameters in a long-term CT experiment conducted in Hungary. Four pairs of similarly sized CT and conventional ploughing tillage (PT) plots were set up in 2003 on Luvisols. The soil samples were collected after 17 years. The total organic carbon (TOC) increased significantly in the 0-15 cm layer at CT sites compared to those in PT, indicating a total increase of 5.22 tha-1 TOC stock. In addition, the increasing biological activity and improved soil structure were the most important processes at the CT sites. Furthermore, more complex humic substances with higher molecular weights are characteristic of water-extractable organic matter (WEOM) as a result of CT. The potentially available nitrogen, phosphorus and potassium were also measured with a relatively high response ratio. Slowly changing parameters, such as cation exchange capacity and base saturation, are important soil physical and chemical parameters, but are not good indicators of the impact of tillage practices. Based on principal component analysis, we suggest the use of water-extractable organic C, amino-nitrogen, water-stable aggregates, available P and K and photometric analysis of WEOM to identify the soil improving processes. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 Síkfőkút 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. [ABSTRACT FROM AUTHOR]

Enzymes are considered to be a key soil component catalysing important transformations related to decomposition and nutrient turnover, and their activity in soil can be used as a measure of soil health. As part of the Síkfőkút DIRT (Detritus Input and Removal Treatments) Project in a temperate deciduous forest in northern Hungary, we examined the extent to which enzyme activity in soil is influenced by both the quality and quantity of plant detrital inputs. DIRT treatments include doubling of leaf litter and woody debris inputs as well as removal of litter and trenching to prevent root inputs. Our objective was to examine seasonal dynamics of soil phosphatase and β-glucosidase activities and to determine the effects of detrital manipulations on these dynamics. We found that the litter additions did not affect enzyme activities, but removal of roots caused significant decreases in enzyme activities. We conclude that plant-induced changes to soil enzyme activities are driven primarily by readily available, labile carbon provided by root turnover and root exudation rather than by aboveground detrital inputs. However, these results could also have been affected by changes in soil chemistry with detrital input removal: after only 6 years of litter removal, soil cation content decreased and soils became more acidic, both of which could inhibit enzyme activity. The soil phosphatase and β-glucosidase enzymes measured showed similar seasonal dynamics. Both enzymes showed the highest activities in spring coincident with high soil moisture and, presumably, high root activity. The minimal response of soil enzyme activity to dramatic litter additions suggests a level of resilience in ecosystem function in this forest, and suggests that aboveground litter is not a significant source of labile carbon to microbes in the mineral soil. [ABSTRACT FROM AUTHOR]

Over the last three decades, increased temperatures and reduced annual precipitation have resulted in significant changes in several Central European deciduous forests. These effects include changes in soil moisture content and detritus production. Within the framework of a detritus manipulation experiment carried out in an old-growth Quercetum petraea-cerris community, we examined how changes in detritus inputs affect soil moisture content and microbial activity within six treatments. CO release and microbial enzyme activities are known to be highly sensitive to environmental factors such as soil moisture and detritus inputs. We applied three detritus removal (No Litter, No Roots and No Input) and two detritus addition (Double Litter and Double Wood) treatments. Although the plots received the same amount of precipitation, the various detritus inputs caused significant differences in soil moisture. Treatments excluding living roots had the highest moisture levels, while the treatment excluding only aboveground detritus inputs had the lowest. CO release, arylsulphatase activity and saccharase activity showed significant seasonal differences with the highest values occurring in spring. Moisture content had a significant positive correlation with CO release, and enzyme activities of the plots were affected by the quantity and quality of detritus inputs. Arylsulphatase activity showed the strongest correlation with soil moisture content ( R = 0.62 in the control plot) followed by CO release ( R = 0.61) and finally saccharase activity ( R = 0.42). We observed that there was a remarkably weaker correlation between soil moisture content and the three parameters in the detritus removal treatments ( R values between 0.56 and 0.13) than in the Control and detritus addition treatments ( R values between 0.72 and 0.42). The correlation between the three parameters of interest and soil moisture content weakens considerably under drought conditions relative to the optimal moisture range of soil moisture content for microbial activity. If the amount of precipitation in the area continues to decrease as anticipated, then litter production and soil microbial activity may be reduced. [ABSTRACT FROM AUTHOR]

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We are doing biological and chemical water quality assessments for 2 drainage systems on Nagyvájás Canal and Keleti-öv Canal as well as Canal of Máriapócs in Nyírség region (Hungary) since 2008. The main goals of the present study were to determinate macroinvertebrate taxa (bioindication for calculation of the BBI and to do comparative analytical examinations at encountered of the two canals. Because we have found flacons including chemical residua at the Nagy-vájás monitoring sampling stations, there is a possibility of a stronger pollution. In case of Canal Máriapócs, we compared the water quality of the in- and outflow section of the reservoir Levelek. We could state that in cases of Keleti-öv- and Nagy-vájás Canal the quality of the water is excellent, based on the used methods and the parameters we examined. On the basis of macroinvertebrate taxa, the water flows could be classified into the moderately polluted quality class. The most common taxa are: Asellus sp., Plea sp., Chironomidae, Ilyochoris sp. and Caenis sp. The water body of this canal is not affected by human activities appreciably although the growing rate of tourism would be unfavorable on water quality and macroinvertebrate communities. [ABSTRACT FROM AUTHOR]

During our work we are going to introduce the following methods: using bioindication for high school education, popularizing an effective method for environmental education, providing exercise focused professional knowledge. The Belgian Ministry of Public Health started to use the Belgian Biotic Index method in 1978, which was tested by several laboratories, and used as the official biological water labeling method since 1984. BBI's simplified version, which can be used also for secondary school education, is the BISEL, which is fast, does not require huge investment, and integrates the taxonomy, the ecology and chemistry. We use zoological taxonomy to determinate macroinvertebrate taxa. Familiarizing the program for wider audience should be a good opportunity to educate natural science in a more effective, exercise focused way. Our most important result is that these can be executed by high school students, who should gain routine on field work and water quality monitoring; therefore we can help their environmentally aware development. One of the most important tasks of these schools is to create the chance for the new generation, so they will be able to operate local communities in a sustainable way. [ABSTRACT FROM AUTHOR]

• Climatic and geochemical factors control carbon sequestration of soils. • Síkfőkút is a unique site in DIRT network with its driest climate and higher CEC. • Due to increasing SOC, physicochemical soil properties change together. • The changed properties can further increase the carbon sequestration in the soil. • Soil texture, pH and CEC are important in predicting the carbon sequestration. The interactions of climatic and geochemical factors control soil organic carbon storage capacity and turnover. The comprehensive evaluation of the effect of long-term detritus manipulation on the soil organic carbon, soil-forming processes and the soil physical and chemical properties will help us better understand the carbon sequestration of forest soils. The long-term (19 years) effect of detrital input and removal treatments (DIRT) on physicochemical soil properties were investigated at a Central-European forest site (Síkfőkút, Hungary). In contrast to the results of similar experiments in other parts of the world, the detritus input treatments affected the soil organic carbon and almost all of the soil physicochemical indicators for the upper 15 cm layer. Soil pH, potential acidity and base saturation decreased in the litter removal plots and increased in the detritus doubling treatments. A decrease in organic matter content in the litter removal plots explained the changes in bulk density, as the stability of aggregates also decreased with the decrease of exchangeable bases and organic colloids. In this respect, compared to the other DIRT sites and other similar experiments in the world, our experimental site is considered unique, as it has the highest clay content and the driest climate. We conclude that potential cation exchange capacity and base saturation (exch. Ca) play a fundamental role in predicting the occurrence of the carbon sequestration mechanisms. We suggest to include these parameters into current SOC models. [ABSTRACT FROM AUTHOR]

The basic aim of the present study is the water quality assessment of the Igrice marsh (Nature Conservation Area, situated in boundary of town of Nyíregyháza, northeastern part of Hungary) using by bioindication and chemical analysis. The phenomenon of biofiltration is well known: the different wetlands are efficient at removing nutrients and pollutants from through-flowing water by means of their plant communities (mainly reedy, tussocky and large sedge areas). Considering the thought mentioned above, the basic questions of this study were the followings: how does the quality of water flowing through the marsh change and how is it manifested in the presence or even absence of the different macroinvertebrate taxa and in the chemical parameters? The water quality assessment was made by using the Belgian Biotic Index (BBI), an index based on the presence or absence of aquatic macroinvertebrate taxa and by chemical parameters (conductivity, pH, NO2- , NO3-, NH4+, Cl-, Fe2++Fe3+, orthophosphate). In accordance with the expectations, the results indicated that stream water, flowing through the marsh has been improved in quality by biofiltration processes of the wetland ecosystem. It could be seen based on the presence of the taxa indicating better water quality and the positive changes in the chemical features at the outflow part of the canal. As a conclusion, it could be established that the Igrice-marsh is able to improve the quality of the through-flowing water effectively. Nevertheless, using this wetland for such a function is not possible, because the habitat of the marsh is protected and there is no information about the effective buffer capacity of the area. [ABSTRACT FROM AUTHOR]

• Long-term, field-scale comparative study of conventional and conservation tillage. • Novel runoff and soil loss data from warm-summer humid continental climate zone. • Soil loss an order of magnitude below its tolerable value on conservation tillage. • Random Forest modelling was used to analyse runoff and soil loss data of 16 years. Conservation tillage (CT) is of primary importance in food security, soil conservation, and sustainable development, even though its comprehensive effects on runoff (RO) and soil loss (SL) are still not fully understood. In 2004, a field-scale study was launched in southwest Hungary to investigate the long-term (16 years) effects of CT on RO, SL and soil, under a warm-summer humid continental climate. Four, especially large, 1200 m2 plots (2 ploughing tillage (PT) and 2 CT) were established, using a special, two-channel collection system. By the end of the study period, significantly higher water-stable aggregates (PT: 20.0 %, CT: 30.4 %), higher soil organic matter (PT: 1.4 %, CT: 1.9 %), greater earthworm abundance (4.9 times that in PT plots) was recorded on the CT plots. Conservation tillage decreased surface RO by 75 % and SL by 95 %. The difference between PT and CT was significant for mean annual soil erosion, with values of 2.8 t ha−1 and 0.2 t ha-1, respectively. The exceedance of extreme precipitation events was <2%, but their impact on soil erosion was extraordinarily high. Runoff and SL were predicted for the whole dataset, and for the sub-dataset of maize culture, in four separate Random Forest (RF) model developments. The often used linear models are not suitable for predicting soil erosion, hence a more robust, non-parametric, advanced method of classification tree analysis was used. The RF classification method was able to predict erosion risk. For the maize sub-dataset, the RF model best predicted the extreme events, followed by the no-runoff category. The sensitivity of the groups with the highest and lowest risk all exceeded 82 % for SL and 64 % for RO. Tillage type was the most important factor. This long-term study demonstrated that the use of CT enabled the maintenance of a major fraction of precipitation on arable land, and consequently, soil loss remained an order of magnitude lower than its tolerable value. The RF method is suitable for modelling RO and SL. In future, the integration of more datasets in modelling would considerably improve the precision and accuracy of prediction of RO and SL. [ABSTRACT FROM AUTHOR]