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The Alpine ecosystem is very sensitive to climatic changes, which have an influence on glaciers, snow, vegetation and soils. The aim of this review is to illustrate the effects of global change on the Alpine soil ecosystem, which is an optimal marker to record them. The manuscript enhances our understanding of the global change effect on the Alpine environment: on morphology, on ice, on vegetation and points out how the cycles of soil nutrients equilibrium have been changed with a direct effect on soils that support plant species. The changes in cryosphere, glacier reduction and periglacial environment as glaciers retreat, decrease in the snow cover extent and earlier snowmelt, determine an effect on soils (on the structure, organic matter and humus forms, soil processes and soil types) from the top of the Alpine horizon to the bottom. The processes induced by climate change (such as erosion and tree line shifting) have a direct effect on water balance that can be observed on soil profile characters with an effect on upward migration, change in phenology, extensive losses of species. The equilibrium of the biogeochemical cycles has been changed and this has a direct effect on soils that support plant species.

Oriental beech (Fagus orientalis Lipsky) is the most important and valuable industrial wood species in the Hyrcanian forests in the north of Iran mainly used for furniture, veneer, composite, and papermaking industries. The present research was conducted in 2014 aimed at investigating the physicochemical changes of the felled oriental beech stumps over a 2-25 year period, and likewise the feasibility of using the given stumps as an alternative resource for wood pulp production. To do so, the effects of in-situ decay of beech stumps on their physical (wet and dry weights of wood, wet apparent density, and dry apparent density) and chemical (cellulose, hemicellulose, lignin, extractives, and total mass of carbohydrates) properties over a 2-25 year felling period were studied. The effects of the given decay period were also studied on the obtained Kraft pulp yield and Kappa number. The results indicate that the wet and dry apparent densities as well as the wet and dry weights of the wood samples decreased over the study period. Also, the results show that approximately 30% of the total mass of carbohydrates was degraded by the ambient fungi over the initial two years of felling, whereas the same property was reduced by 60% after 25 years. The Kraft pulp yields obtained from 2- and 25-year decayed stumps were 22.5% and 8.4%, respectively. The fungal degradation of wood chemical compounds could considerably reduce pulp yield and Kappa number by 62.8% and 74.2%, respectively. The results of a stepwise multivariate regression model evidence that cellulose not only affects the Kappa number but also owns a greater share (vs. lignin) in modelling the Kappa number. This reveals that the intensity of cellulose degradation, due to fungal exposure, is significantly higher than that of the other components of beech stumps in the studied forest area.

This study was done to quantify the amount of soil organic matter and to evaluate physicochemical properties and vegetation cover changes along the altitudinal gradient. Nine altitudinal transects were selected from 100 m a.s.l. to 1 700 m a.s.l. Then, 160 circular plots of 1 000 m2 area with a distance of 150 m from each other were studied. Soil texture, bulk density, particle density, soil base saturation, phosphorus and potassium values did not indicate any specific variation pattern. Whereas pH decreased powerfully, the highest and the lowest value of pH was measured at 100 m a.s.l. and 1 700 m a.s.l., respectively. Soil organic carbon content increased significantly with increasing altitude (P ≤ 0.01). Density of trees decreased dramatically from 100 to 900 m a.s.l., whereas this trend was ascending from 1 100 to 1 700 m a.s.l. Density of shrub species increased with increasing altitude along the gradient and the highest value was revealed at 1 300 m a.s.l. The highest percentage of herbaceous species cover was found at a lower altitude and a decreasing trend was found along the altitudinal gradient.

The study focused on natural regeneration of European beech (Fagus sylvatica), Norway spruce (Picea abies) and European larch (Larix decidua) within very small and four times bigger size gaps following a disturbance at a mixed temperate forest in the Czech Republic. In spring 2013, experimental gap design starts, when 1 m2 circular sampling plots along transects were delineated within four selected naturally occurring canopy openings with size below 20 m2. In December 2013, these initial canopy openings were artificially enlarged by felling to 226 m2 for small and 904 m2 for big gaps. Regeneration was monitored in the next two consecutive growing seasons after disturbance. Light conditions were measured before and after disturbance. Results indicated that four times larger gaps increased twice levels of light conditions, and that diffuse light starts to equilibrate to direct light there. Large gaps were favouring larch regeneration. Beech regeneration was predominant, independently on gap size as the study area belongs naturally to Beech Forest Vegetation Zone, however, the decline of spruce regeneration was presumably linked to drought. Gap size explained variation of larch regeneration in gaps. Contrarily, gap size could not be associated with the prolific regeneration of beech and abysmal regeneration performances of spruce in gaps.

Because of generally small log piles, loading forwarders during thinning is time consuming. The Assortment Grapple, an innovative grapple with an extra pair of claws which facilitates the handling of two assortments during one loading crane cycle, has been designed to decrease forwarders' loading time consumption. A standardized experiment was performed in a virtual thinning stand using a machine simulator with the objectives to form guidelines for working with the Assortment Grapple and to analyse its development potential. Four experienced operators participated in the study. According to the results, the Assortment Grapple's accumulating function is beneficial only when there are no remaining trees between piles loaded during the same crane cycle. In such cases, none of participating operators lost time, and 3 of 4 operators saved time notably. The problem with the remaining trees is the extra time required to steer the crane tip around them. Therefore, a harvester should place those log piles that are later to be forwarded together in the same space with no remaining trees between the piles. Furthermore, we recommend that the Assortment Grapple's usability will be improved by adding an own rocker switch on the forwarder's controls to command the extra claws.

We investigated moth larvae (Lepidoptera) developing in temperate forests in Central Europe shortly after the tree budburst (the "brumata-viridana complex"). Larvae were collected in southern Slovakia in May 2015 and May 2016 from young and mature trees of late flushing Quercus cerris L. and early flushing Q. pubescens Willd. Although Q. cerris yielded fewer species (40 species) than Q. pubescens (47 species), the rarefied number of species and the Chao index suggested a similar number of species on mature trees of both oak species. Both the total number of moth larvae in assemblages and the abundance of dominant species (pests) were significantly lower on Q. cerris than Q. pubescens. The results suggest the release of Q. cerris with delayed budburst from heavy infestations by folivorous moth larvae. Knowledge obtained can be applied in silvicultural and horticultural practices aimed to protect and maintain forest, fruit, and ornamental trees.

In June 2018, the presence of one adult specimen and one egg cluster of the North-American oak lace bug Corythucha arcuata were recorded near the village of Mužla, close to the Danube River, in southern Slovakia. They were found on leaves of Quercus cerris growing in a mixed stand. In August 2018, other specimens (nymphs and adults) were observed on Quercus robur leaves, near Čičarovce, in eastern Slovakia. This is the first record of C. arcuata in our country. The oak lace bug probably reached us while invading from Hungary, where heavy infestation is reported from several parts of the country.

Ambrosia beetles are among the most damaging forest pests. They are frequently moved intercontinentally and are therefore subject to quarantines. The objective of the current research was to determine whether two commercially produced lures for Trypodendron species also attract central European ambrosia beetles. In 2018, Theysohn^® traps were deployed in an oak forest that also contained hornbeam and linden trees. Five pair of traps was baited with the standard synthetic pheromone lures, Trypowit^® or Lineatin Kombi^®. The 201 adults of ambrosia bark beetles that were trapped were identified to eight species, which represents almost the entire spectrum of oak ambrosia scolytids in the region. Trypodendron domesticum, Xyleborinus saxesenii, and Xyleborus monographus were the most abundant species and exhibited a slight preference for the lure with a higher content of alcohols (Lineatin Kombi^®). Both lures attracted T. lineatum because both contain lineatin. The number of beetles trapped was low probably because food sources (damaged or wilting oaks) were rare and because the forest was surrounded by agricultural land and therefore isolated from other oak forests.

In order to understand and clarify the impacts of straw return on maize production and field CO₂ emission in Northeast China, the most important agricultural base of the nation, a field experiment was conducted in 2012-2015, including no straw return (CK), straw amendment at 4000 kg/ha (S₄), and at 8000 kg/ha (S₈). The average grain yield was found significantly promoted by the two straw treatments, with comparably increased magnitudes of 11.0% and 12.8% for S₄ and S₈, respectively, and the benefits were gradually enlarged with increasing experimental duration. Although straw return tends to reduce slightly the harvest index, it was detected that it exerted significantly positive impacts on nitrogen harvest index. These results implied that added straw could lead to raising grain yield and enhancing nitrogen use efficiency simultaneously. In 2015, our monitoring showed that CO₂ emission was elevated with intensified use of straw, and S₄ and S₈ decreased carbon emission efficiency by 7.3% and 13.6%, respectively. However, there was no statistical difference between S₄ and CK. Overall, straw addition at the rate of 4000 kg/ha accompanied with inorganic fertilizer was recommended to be adopted in Northeast China, which was considered as a sustainable and relatively environment-friendly agricultural technique during maize production.

Secondary fertilisers are becoming an important alternative to conventional mined fertilisers. For the first time, the struvite "relative" hazenite (KNaMg₂(PO₄)₂∙14 H₂O) has been artificially synthesised. A pot trial assessed whether hazenite-fertilised ryegrass had comparable potassium (K), magnesium (Mg), or phosphorus (P) uptake and shoot yields with treatments receiving conventional K (muriate of potash), Mg (kieserite) or P (triple superphosphate, TSP) fertilisers. Ryegrass shoot biomass production and K/Mg uptake in replicates receiving hazenite were as good as or superior to those amended with conventional fertilisers. Phosphorus uptake of plants whose P source was TSP was significantly higher than that of the hazenite-amended replicates without significantly higher shoot biomass, indicating luxury P uptake. Hazenite's constituent sodium (Na) makes it a potentially useful soil amendment for forage grasses or natrophilic crops such as sugar beet. Its component Mg would also be desirable in forage grasses to pre-empt ruminant hypomagnesemia or in crops with a relatively high Mg demand, for example, maize. Furthermore, hazenite represents a good alternative to KCl for chlorophobic crops such as potatoes. However, given its unusual ratio of Mg, P, and K, the ideal application of hazenite would probably be in combination with other fertilisers.

To investigate how clipping (CL) regulates the effects of nutrient addition, an experiment, including CL and nitrogen (N) addition, was conducted in an alpine meadow. Nitrogen treatment increased community coverage (48-113% higher than the control) and aboveground biomass (29-117% higher than the control), which was mainly attributed to grass growth. Both N and N + CL treatments showed a tendency to reducing species richness, while significant reduction only occurred in 2016 and 2017 in CL treatment. Clipping showed a tendency to decrease community cover (3-37% lower than the control) and aboveground biomass (2-34% lower than the control), while N + CL treatment had no effect, indicating that clipping can eliminate the simulated effects of N addition. Nitrogen addition significantly increased soil inorganic N (SIN, 528-1230% higher than the control), while SIN in N + CL was 25-48% lower than N treatment. The decrease in stimulated effects in N + CL was attributed to SIN decrease, which resulted from the aboveground biomass removal by clipping. Our results show that clipping can take away aboveground biomass and cause soil nutrients to decrease, which slows down the degraded grassland recovery. This suggests that grazing exclusion may eliminate the effect of nitrogen deposition on aboveground production in alpine grasslands.

A three-year pot experiment carried out in the vegetation hall in 2014-2016 included studying the enzymatic activity of soil, into which various amounts of copper: (100, 200 and 300 mg Cu/kg soil) and organic materials (cattle manure, chicken manure, post-mushroom substrate) were introduced, used separately, at a soil-introduction dose of 2 g C_org/kg. Copper and organic materials were used once, only in the first year of the study, before sowing test plant orchard grass. In soil collected after the last (fourth) swath of grass in each year of the study, the activity of urease, dehydrogenases, acid, and alkaline phosphatase was determined. Applications of copper to the soil, regardless of its dose, resulted in a decrease in urease, dehydrogenases and alkaline phosphatase and an increase in acid phosphatase activity. The inactivating effect of this metal on the activity of urease, dehydrogenases and alkaline phosphatase increased with the increase of its dose. Organic fertilisation generally increased the enzymatic activity of the analysed soil. In subsequent years of the study, urease and alkaline phosphatase activity decreased, while acid phosphatase activity increased. Dehydrogenase activity did not change significantly in subsequent years of the study.

Agronomic zinc (Zn) biofortification of crops could help to alleviate dietary Zn deficiency, which is likely to affect more than one billion people worldwide. To evaluate the efficiency of agronomic Zn biofortification of broccoli, four application treatments were tested: no Zn application (control); soil application of 5 mg/kg ZnSO₄.7 H₂O (soil); two sprays (15 mL/pot each) of 0.25% (w/v) ZnSO₄.7 H₂O (foliar); and soil + foliar combination. Soil Zn application increased Zn-DTPA (diethylenetriamine pentaacetic acid) concentration by 3.7-times but did not affect plant growth or plant Zn concentration. Foliar Zn application increased stem + leaves and floret Zn concentration by 78 and 23 mg Zn/kg, respectively, with good bioavailability based on phytic acid concentration. Boiling decreased mineral concentration by 19%, but increased bioavailability by decreasing the phytic acid concentration. The entire broccoli could constitute a good nutritional source for animals and humans. An intake of 100 g boiled florets treated with the foliar treatment will cover about 36% of recommended dietary intake (RDI) of Zn, together with 30% of Ca, 94% of K, 32% of Mg, 6% of Na, 55% of P, 60% of S, 10% of Cu, 22% of Fe, 43% of Mn, and 35% of Se RDIs.

Zinc (Zn) insufficiency and water deficiency are primary challenges in intensive rice production systems. This study aims to examine the influence of two irrigation regimes, flood irrigation (FI) and water-saving irrigation (WSI), on rice grain yield and mobile Zn accumulation in soil and rice grains. Experiments were conducted in An Vien rice fields in the Tien Lu district, Hung Yen province, located in the middle of the Red River delta during four rice seasons from 2015 to 2016. The results showed that the WSI regime dramatically increased the grain yield and Zn concentrations in grain of rice. Grain yield was increased by 14.76% and grain Zn concentration by 17.93% when compared with the FI regime. The decrease in the mobile Zn concentration in soil was only 5.7% in the WSI technique, compared with 73.6% for FI techniques. Therefore, it can be concluded that WSI can be effective agricultural practice to elevate grain yield and increase Zn retention in soil and bioavailability in rice grains.

The aim of the study was to assess soybean response to sowing material inoculation with HiStick® Soy preparation, containing Bradyrhizobium japonicum. Based on the obtained results, it was found that the inoculation significantly increased the number and dry weight of nodules on soybean roots compared to control. The bacterial preparation significantly increased the number of pods per plant. As a result, a significant increase in seed yield (0.58 t/ha) was obtained compared to control. HiStick® Soy increased total protein content in seeds. Protein and fat yield was higher after seed inoculation by 318 kg/ha and 101 kg/ha, respectively, compared to control.

In the years 2011-2014, winter wheat grain yield, qualitative and economic parameters were evaluated according to different fertiliser treatments: (1) control: unfertilised treatment; (2) farmyard manure (FYM) and (3) FYM + NPK (farmyard manure applied together with mineral NPK). The highest yields (8.10 t/ha) were recorded in the FYM + NPK treatment, while significantly lower yields (6.20 t/ha and 5.73 t/ha) were recorded in FYM and control treatments, respectively. Similarly, statistically significantly higher values of the quality parameters were found in the FYM + NPK treatment (13.55% of crude protein content and 43.56 mL of Zeleny's sedimentation test), compared to control (10% and 22.44 mL, respectively). The modelling expert system (AGROTEKIS-Crop Technology and Economy) was used for the evaluation of economy. This software is based on technological methods of cultivation and norms of material input costs and costs of individual mechanised works. The economic benefits and profitability were evaluated for three different levels of grain market price. The highest gross profit per ha was recorded in the FYM + NPK treatment. According to the gross profit, the control treatment provided better results than the FYM treatment.

Barnyardgrass (Echinochloa crus-galli (L.) P. Beauv.) is one of the most yield-limiting weeds in rice in Turkey. Barnyardgrass resistance to common herbicides has been reported worldwide; however, such information is largely lacking in the country. The objective of this study was to determine the resistance spectrum of different barnyardgrass populations to the most commonly-used herbicides in rice in Turkey. The susceptibility of 40 barnyardgrass populations was evaluated. The samples were collected from fields with intensive rice cultivation in Balikesir and Çanakkale provinces. Seeds were picked from barnyardgrass plants suspected to be herbicide-resistant because of their survival in the rice fields after herbicides application. A total of 38 populations were resistant to penoxsulam, and the resistance index of these populations ranged from 2 to 39. A total of 24 out of the 38 barnyardgrass populations showed a GR₅₀ (herbicide dose causing a 50% reduction in plant dry matter) value higher than the recommended penoxsulam dose (20.2 g a.i./ha) in rice. Among these 24 barnyardgrass populations, 25, 29.2 and 45.8% populations exhibited high, moderate and low level of penoxsulam resistance, respectively. From the penoxsulam-resistant populations (38), the response of 14 populations (low to high resistance to penoxsulam) to six commonly-used herbicides for barnyardgrass control in rice was evaluated. The selected 14 populations showed resistance to almost all herbicides tested, with the lowest average resistance being determined against profoxydim and the highest average resistance against molinate herbicide. Resistance levels against six commonly-used herbicides in rice ranged from 2 to 34.

The traditional management applied by the Native Community of Chambira (NCCh) is based on agroforestry plots with diverse species and areas with rotation of legumes, cassava and maize. The objective was to evaluate behaviour of the physicochemical indicators of soil quality with traditional crop management in the NCCh. A completely randomised design was applied, where the treatments were traditional mixed fruit management (MF), crop rotation (CR) and native forest (NF) as reference. Physical indicators of the surface layer did not show differences, the apparent density (AD) and the resistance to penetrability (RP) increased with depth; chemical indicators differed in the MF and CR had higher results compared to NF. The AD and RP had a significant negative correlation with soil organic carbon (SOC) and positive correlation between SOC, P, Ca, Mg, K available and cation exchange capacity. The MF and CR managements developed in the NCCh are techniques with great potential for soil conservation.

One of the most serious threats facing agricultural productivity in the world is unfavourable soil conditions. Several studies have shown that almost half of the world's land-mass is affected by either natural or human-induced pollution. This, therefore, poses a threat to agricultural improvement needed to tackle the problem of a continuous increase in the world population. The emergence of soil extremophiles with plant growth-promoting trait has proven to be a reliable means to quell the threat posed by some factors limiting soil potency. Adopting these organisms as bio-inoculants will easily proffer a solution to both biotic and abiotic soil stress. As such, the natural bio-fertilisers will help to improve the quality of the soil by making it healthy enough to sustain sufficient plant growth. This review gives an overview of the multifarious importance of extremophiles on plants grown under harsh soil conditions, with the multifaceted application of omics as a means to unveil these organisms and their benefits for environmentally sustainable agricultural systems and food safety.

Matching the planting density, fertilisation, and genotype is crucial to improve the maize yield. Here, two-year field trials, including 4 densities and 3 nitrogen (N) rates for 2 maize cultivars, were conducted to study the effects of planting density and N rate on maize growth, lodging, spike characters, and yield. Compared with 360 kg/ha, N application of 180 kg/ha decreased the plant, ear height, and stem circumference of WeiKe 702 (WK702), while increased the plant height and stem circumference, but decreased ear height of ZhongDan 909 (ZD909). Meanwhile, the N application of 180 kg/ha greatly reduced the lodging rates of maize under the high density. The maize yield increased and reached the maximum yield at 7.5 × 10⁴ plant/ha, and then decreased with increasing density. The N application of 180 kg/ha increased yield by 0.49, 0.73, 5.38, 7.81% from low to high planting densities, and reduced the bald tip length by 18.86%. WK702 was more sensitive to the planting density and N application, with greater variation of yield and spike traits than ZD909 under the densification. Therefore, the N application of 180 kg/ha and a density of 7.5 × 10⁴ plant/ha could improve maize growth and lodging, and therefore increase maize yield.

The objective of this work was to investigate, before and after chemical treatment, the interrelationships of the physiological quality tests in wheat grains. Following the chemical treatments with (i) carboxin thiram; (ii) carboxin thiram + thiamethoxam; (iii) carboxin thiram + thiamethoxam + bio-stimulant; (iv) pyraclostrobin + methyl thiophanate + fipronil, and (v) pyraclostrobin + methyl thiophanate + fipronil + bio-stimulant, subsequently the grains were assessed for their physiological potential. The physiological potential of the grains could be differentiated based on the electrical conductivity, seedling growth, and emergence in sand tests. In conclusion, the use of the active ingredients changed the correlation between laboratory tests with crop emergence in the sand as well as altered the relevance of the tests for sorting the treated grains into different physiological potential. But, the seedling growth tests and the electrical conductivity were, together, the parameters most relevant for explaining the data variability.

The aim of this study carried out in 2017-2018 was to determine the effect of white cabbage (Brassica oleracea L.), which is known to have an allelopathic effect on the germination of some weed and cultural crops seeds. In addition to weeds, Amaranthus retroflexus L., Chenopodium album L. and Solanum nigrum L., cultural plants such as Zea mays L., Beta vulgaris L., were used in this study. It has been shown that the seed germination rate was decreased by the increased concentration of white cabbage post-harvest leaves extractions, which were made with different concentrations of aqueous and methanol extracts (30, 40, and 50%). The methanol extract was found to be more effective in germination. According to these results, S. nigrum and Z. mays seeds were less affected than A. retroflexus, C. album and B. vulgaris seeds. In the light of these data, it is observed that extracts obtained from white cabbage can be effective on some weeds; however, it was concluded that in order to reach more definite conclusions, studies on the subject should be increased, and similar studies should be continued under greenhouse or field conditions.

Glomalin is one of the factors with an important role at forming and stabilising soil aggregates. Long-term stationary experiments were carried out to observe the influence of various fertilisation treatments on the content of glomalin in topsoil. The content of easily extractable glomalin (EEG) and total glomalin (TG) were determined. Moreover, glomalin was also determined by using the near-infrared reflectance spectroscopy (G_NIRS). Both mineral and organic fertilisation significantly increased the content of glomalin compared to the unfertilised control. However, observed differences among individual fertilisation treatments were not significant. A significant correlation was determined between the content of EEG, TG, G_NIRS, and the content of humic substances as well as humic acids. Both methods used (EEG, TG) can equally reflect soil organic matter quality. A significant correlation was also recorded between the G_NIRS and extraction methods (EEG, TG).

The study focused on the effects of gap size on natural regeneration of European beech (Fagus sylvatica L.) and Norway spruce (Picea abies L.) and micro-environmental soil conditions in gaps of different sizes under temperate mixed forest in the Czech Republic. Six gaps comprising two for small (≥ 200 m²), medium (≥ 500 m²) and big (≥ 900 m²) each were selected. Ten circular 1 m² subsampling plots were established at 2 m intervals along individual North-South-East-West transects, including one at the gap centre. Regeneration was monitored in 2014 and repeatedly in 2019. Soil conditions were only measured in 2019. Gap size was found to be a significant parameter for European beech natural regeneration in 2014. Besides, the quick occupation of European beech in gaps at natural beech zone provoked its prolific regeneration compared to Norway spruce in 2014. However, in 2019 the recent threat of weather variabilities was responsible for the general abysmal growth performance of natural regeneration. Division of gap microsites into different within-gap positions based on prevailing light or shade conditions was helpful in assessing the significant variations of soil conditions within-gap positions and among gap sizes. Soil temperature and moisture significantly influenced the regeneration of European beech and Norway spruce, respectively.

Eggshell is a solid waste, with production of several tons per day. Eggshell is mostly sent to the landfill with a high management cost. It is economical to transform the eggshell waste to create new values from these waste materials. The present article is an attempt to summarize the possible applications of eggshell. The eggshell waste can be used (a) at biodiesel production as a solid base catalyst used for biodiesel pollutants minimization, reducing the production costs of biodiesel and making the process of biodiesel production fully ecological and environment-friendly; (b) as an absorbent of heavy metals from wastewater as it is a serious environmental problem in the ecosystem; (c) as biomaterial in order to replace bone tissues due to the rise in the number of patients; (d) as a fertilizer and calcium supplement in nutrition for human, animals, plants, etc. Number of research articles have been included in this review to describe a methodical growth in this subject matter.

The article demonstrates a multilevel method of soil degradation analysis on land within South Moravia (Czech Republic (CZ)), in the Hodonín region, which is among the highest producing agricultural regions in CZ. The analysis takes a top-down approach, from a regional scale, through cadastres, to individual blocks of land. In the initial (rough) phase, selection was based on the Soil Degradation Model created for the Czech Republic, which classifies the extent of soil degradation to a cadastral level. Within the chosen region, the Čejkovice cadastre is the most burdened in terms of the combination of various degradation factors, and was therefore chosen for a further level of analysis in the form of remote sensing. The results of remote sensing and image classification identify areas with a high level of water erosion, which is the most significant degradation factor within CZ. Pedological research was then carried out in these identified areas. The results of both approaches were compared, and showed significant differences between erosional areas and depositional areas of slopes, which confirms their suitability for the given form of research and analysis. A combination of the given general (Degradation Model) and more detailed methods (erosion modelling, image classification and soil sample analysis) can find practical application in the optimization of farm production in the rural landscape.

The use of sludge in agriculture within the European Union (EU) is currently regulated only by the limits of heavy metals (Cd, Cu, Hg, Ni, Pb and Zn) listed in Council Directive 86/278/EEC. This document is now more than 30 years old. Several European countries have introduced more stringent requirements in comparison with the directive, and have adopted limits for concentrations of other heavy metals, synthetic organic compounds and microbial contamination. The paper provides an overview of the current limits of these substances in sewage sludge and concentration limits of heavy metals in soil intended for sludge application, together with applicable laws and regulations in European Union countries. There is a need to update these regulations taking into account the current risks associated with the application of sludge to agricultural land, with the possibility of using ecotoxicological tests to assess the risks. A wide range of technologies for sewage sludge processing is used in EU countries. The predominant choice is a direct application in agriculture followed by composting. The use of sewage sludge in agriculture in 2014 and 2015 in 13 EU countries that provided data amounted to 22.6% (2014) and 22.1% (2015) of produced sludge and 23.3% (2014) and 23.1% (2015) of sludge disposed. It is also highly variable within EU countries ranging between zero (Malta, Slovenia, Slovakia) and 80% (Ireland). Over 50% of sewage sludge is used in agriculture in Bulgaria according to 2015 data.

The effects of tillage and crop rotation on the soil carbon, the soil bulk density, the porosity and the soil water content were evaluated during the 6^th season of an on-going field trial at the University of Fort Hare Farm (UFH), South Africa. Two tillage systems; conventional tillage (CT) and no-till and crop rotations; maize (Zea mays L.)-fallow-maize (MFM), maize-fallow-soybean (Glycine max L.) (MFS); maize-wheat (Triticum aestivum L.)-maize (MWM) and maize-wheat-soybean (MWS) were evaluated. The field experiment was a 2 × 4 factorial, laid out in a randomised complete design. The crop residues were retained for the no-till plots and incorporated for the CT plots, after each cropping season. No significant effects (P > 0.05) of the tillage and crop rotation on the bulk density were observed. However, the values ranged from 1.32 to1.37 g/cm³. Significant interaction effects of the tillage and crop rotation were observed on the soil porosity (P < 0.01) and the soil water content (P < 0.05). The porosity for the MFM and the MWS, was higher under the CT whereas for the MWM and the MWS, it was higher under the no-till. However, the greatest porosity was under the MWS. Whilst the no-till significantly increased (P < 0.05) the soil water content compared to the CT; the greatest soil water content was observed when the no-till was combined with the MWM rotations. The soil organic carbon (SOC) was increased more (P < 0.05) by the no-till than the CT, and the MFM consistently had the least SOC compared with the rest of the crop rotations, at all the sampling depths (0-5, 5-10 and 10-20 cm). The soil bulk density negatively correlated with the soil porosity and the soil water content, whereas the porosity positively correlated with the soil water content. The study concluded that the crop rotations, the MWM and the MWS under the no-till coupled with the residue retention improved the soil porosity and the soil water content levels the most.