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Grassland as a part of farmland is important for agrobiodiversity, soil protection and agricultural production (grazing, hay production). In the Czech Republic, grassland area increases with increasing altitude. In this study we evaluated the period 1966–2021 and the change in grassland area in different locations in South Bohemia region: fertile lowlands (Písek, České Budějovice, Tábor districts) and marginal uplands (Český Krumlov, Prachatice districts). Data on land use including the share of grassland were obtained from the Czech Cadastral and Surveying Office and Czech Statistical Office. In the upland districts, there is the largest share of grassland areas in the whole region. The prevalence of grasslands is probably due to the geographic and climatic conditions, which are challenging here. Our research shows the results of changes in grassland areas between 1967 and 2021, with regard to the assessed districts. The difference in the percent area of grassland in 2021 compared to 1967 is –0.04 to –1.77 for lowlands, and +1.45 to +5.99 for uplands. Despite this, uplands farmers practice relatively extensive farming methods and extensive grazing due to low ruminant numbers. Although farmers maintain relevant carbon sinks, it is unlikely to increase the carbon stocks per hectare of extensive grasslands on an annual basis, which would be a barrier to participation in a carbon farming system.

Evapotranspiration (ET) is one of the main components of the hydrological cycle and plays a crucial role for water resources. It is sensitive to climate change, and therefore, estimating ET under changing climatic conditions is essential in comprehending hydrological processes, particularly in agricultural water management. In this study, the impact of climate change on ET in the Central Anatolia region of Türkiye was assessed. For this purpose, RCP4.5 and RCP8.5 climate change scenarios based on two Earth System Models, HadGEM2-ES and MPI-ESM-MR, were employed for three future time periods: 2025–2049, 2050–2074, and 2075–2098. As a baseline period for comparison, the time interval spanning 1980–2000 was considered. ET values were computed by using the Penman-Monteith equation, recommended by the Food and Agriculture Organization, along with five widely utilized methods. The study revealed a consistent increase in ET depending on the employed methods for the future period in response to climate change. The average of the ET amounts for the region was determined as 1089 mm for the reference period 1980–2000. As the average of the six methods utilized, amounts estimated by HadGEM RCP4.5, HadGEM RCP8.5, MPI RCP4.5, and MPI RCP8.5 models for the future period were obtained as 1 199, 1 285, 1 166, and 1 248 mm, respectively. Considering the results, it is found that the ET amount in the Central Anatolia region of Türkiye will increase by up to 11% by the end of this century under the optimistic RCP 4.5 scenario and by up to 19% under the extreme RCP 8.5 scenario. These findings regarding increased evapotranspiration play a significant role in water resource management and agricultural production planning in the region, holding crucial implications for sustainable agriculture.

The purpose of this study was to evaluate the application of biostimulation and bioventing for the treatment of crude oil-contaminated soils. The research needed to check how various industrial biostimulants will perform in the treatment of contaminated soils and whether or not there is a synergetic effect that has to do with the stimulant composition. Soil samples used for this study were collected from South Africa. The soil samples were air-dried for 24 h and subsequently passed through a standard sieve of 2 mm screen. The soil consists of 79.32% sand (2.00–0.02 mm), 14.71% silt (0.02–0.002 mm) and 5.97% clay (< 0.002 mm). A microcosm system containing 1 kg of soil contaminated with crude oil (5% w/w) for biostimulation (BSTc) treatment was amended with varying ratios of municipal wastewater (MWW) and brewery wastewater (BWW) to investigate the possible synergy. The bioventing (BVTc) treatment involves the supply of atmospheric air to the bioreactors through the vadose zone for 30mins flow duration every 48 h intervals at ambient condition for 28 days. The BSTc and BVTc treatments recorded 48–58% and 54–75% total petroleum hydrocarbon (TPH) removal efficiencies, respectively, as the BWW amendment noted appreciable removal compared to MWW, while the control treatment recorded 35%. The result showed that the attempt to boost the TPH removal efficiency using the bioventing with the wastewater amendment was effective, as the presence of enough oxygen in the system resuscitated the activities of the microbial community for enhanced TPH biodegradation. This study inferred that combined bioventing and biostimulation techniques proved to be an effective bioremediation strategy for the treatment of crude oil contaminated soils and could serve as a vital tool towards the mitigation of pollution aftermath faced by communities involved in oil production and/or processing activities.

Many methods are used in a laboratory for packing sieved soil. Determination of soil properties is expected to vary with the applied packing method. The objective of this investigation was to test the impact of initial soil sieving duration and scraping of exposed soil surfaces on saturated hydraulic conductivity (K_s) of an initially air-dry loam soil determined by the simplified falling-head technique. Two sieving durations (5 and 30 min) were considered. A brush was used to scrape exposed surfaces for half of the tested soil columns. A long sieving yielded finer soil than a short sieving and 9–22% smaller values of K_s. Scraping the exposed soil surfaces yielded 4–17% smaller K_s values than those obtained on the not scraped columns. None of the observed differences was statistically significant. Therefore, sieving duration and treatment of the exposed soil surfaces were minor factors influencing the determination of K_s. Reaching general conclusions about sieving duration and scraping effects requires testing these factors with other soils, initial soil water conditions and K_s measurement techniques.

At the soil level, earthworms are key indicators of water-related processes which help soils to accept, retain, release and transmit water by influencing the soil structure through their burrowing, casts, and drilosphere. The water repellency is an indicator of soil structure stability both for the natural soil and for the earthworm casts (bioturbated soil). The water repellency of earthworm casts is a complex property that should be approached both at ecological and functional level in earthworm categorization because this cast property influences the transport and flow processes in soil, such as those of water, nutrients, pollutants, and gas diffusion. The earthworms have been described as bioremediators of soil water repellency. Casts of the earthworm species Lumbricus terrestris collected from an urban green space have been analysed for particle size composition (texture), organic carbon (OC) content and CaCO₃ content in relation to their water repellency (the hydrophobicity). The findings of this study showed that the main drivers determining the water repellency of the casts of L. terrestris, as indicator of their structural stability, are chemical (the contents of OC and respectively CaCO₃) and physical (contents of clay, silt and fine sand). The water repellency (hydrophobicity) of the casts decreased with their content of clay and silt and increased with their content of organic matter and CaCO₃. The hydrophobicity of earthworm casts is in direct positive relation with their previous water accumulation, i.e. the current penetration time of water increases or decreases if the previous penetration time of the water increased or decreased, respectively. The water drop penetration times indicated that the analysed earthworm casts were slightly water-repellent. A small to medium degree of water repellency has been mostly reported as appropriate for the aggregate stability of the soil.

Soil particle-size distribution or soil texture presents one of the most important physical properties. There are various systems of the classification systems for soil particle-size fractions with different boundaries. Our effort was concentrated on the mathematical approach to evaluate the existing data and convert it to the form of a reconstructed cumulative particle-size curve which will allow reading concentration of any desired particle size. Non-Uniform Rational B-Splines (NURBS) curves therefore represent a generalization of B-splines and Bézier curves by extending the definition by an element of rationality, which is represented by the weights of the control points, and a nodal vector of parametrization, which represents the element of uniformity. The NURBS curve was used for smooth (depending on the degree of the curve used) and as tight as possible approximation of the arranged control points, the connecting lines of which forms a convex envelope for its individual parts. The NURBS approximation curve is therefore determined by the ordered control points and their connecting lines, the weights of these points, the degree of the curve and the nodal vector of parametrization. However, the construction of the approximation curve is primarily dependent on a limited number of points of the experimentally determined particle-size distribution curves, and for curves with significant breaks in the course, one must consider either a lower accuracy of the approximation or the necessity of “improving” the approximation using the weights of individual points, inserting additional points or working with a nodal vector of parametrization. For basic approximation, the PUGIS system (Czech soil information system) offers automatic approximation using all variants mentioned in the article as well as the possibility of individual changes in the weights of control points, in their number and position, and in the nodal vector of parametrization.

This study investigated, for the first time, the efficacy of citric acid (CA) and ethylenediaminetetraacetic acid (EDTA) as electrolytes in electrokinetic remediation (EKR) for removing lead (Pb) and cadmium (Cd) from three distinct soils (Anthrosols soil, AT; Acrisols soil, AC; and Chernozems soil, CH). Under a voltage gradient of 2 V/cm and a remediation duration of 4 days, EDTA proved most effective for Anthrosols, achieving removal rates of 17.8% for Cd and 12.8% for Pb-lower than those observed for Acrisols and Chernozems, likely due to AT’s high pH background. These results suggest that combining EKR with other remediation techniques could enhance efficiency for such soils. For Acrisols soil, extending the remediation time to 10 days significantly improved metal removal: Cd removal reached 91.1% with CA, while Pb removal attained 62.7% with EDTA. Chernozems soil exhibited higher sensitivity to EKR, with pronounced focusing phenomena. In CH1, Cd removal in anode-proximal (S1) zone reached 99%, but accumulation in the cathode-adjacent (S4 and S5) reduced the average removal rate to 22%, indicating the potential for improvement through cathodic control. Similarly, in CH2, Pb removal in S5 achieved 84.8%, while focusing in S1 suggested the need for anodic optimisation. These findings highlight the influence of soil properties and operational parameters on EKR efficiency, providing insights for tailored remediation strategies.

Due to the earthworms’ implications in nutrient cycles through their burrowing and casting activity, earthworms are worth considering when urban biogeochemical cycles are analysed. Several chemical parameters and their relationships were analysed in earthworm casts of two urban parks, namely the pH, total organic carbon (TOC), total nitrogen (Nt), plant available phosphorus (P), plant available potassium (K), and calcium water soluble (Ca). It was statistically significantly found that the TOC, Nt, P and K are reciprocally determined in the earthworm casts: 74.4% of the pH variability is co-determined by the N, P, K, TOC, and Ca contents; 95.9% of the Nt variability is co-determined by the pH, P, K, TOC, and Ca contents; 95.4% of the P variability is co-determined by the pH, N, K, TOC, and Ca contents; 94.5% of the K variability is co-determined by the pH, N, P, TOC, and Ca contents; 86.6% of the TOC variability is co-determined by the pH, N, P, K, and Ca contents. This study revealed the complexity of the chemical relationships inside earthworm casts, their reciprocal dependencies, and highlighted the complexity of the earthworms’ contribution to biogeochemical cycles in urban areas. Our findings propose earthworms as indicators of the integrative conservation management of urban ecosystems.

This study investigates the effects of repeated applications of the non-ionic soil surfactant H2Flo (ICL-SF Inc., Israel) on the soil water content, hydraulic conductivity, nutrient distribution, and organic carbon fractions (OCFs) in non-hydrophobic loamy sand soils under subsurface drip irrigation. Our results indicate that H2Flo treatment reduces both saturated and unsaturated hydraulic conductivity while promoting the uniform irrigation distribution, consistent with previous findings on surfactants’ effects on sandy soils. An increase in soil pH levels, organic carbon content, and extractable magnesium, calcium, and potassium was observed in treated soils, with elevated levels of potassium permanganate oxidizable organic carbon (POXC) implying accelerated decomposition rates. Notably, a positive linear relationship was found between POXC and the increased NO₃^–-N content of treated soils, suggesting induced conditions of nitrification. However, the carbon fractions water-soluble organic carbon (C_ws) and hot water-soluble organic carbon (C_hws) remained quantitatively unchanged, even though they exhibited a positive linear relationship with the soil’s hydraulic conductivity. The study highlights the crucial role of monitoring changes in OCFs and nutrient dynamics after surfactant application to optimize soil organic matter utilization and chemical fertilizer management.

In this study, activated carbon derived from Monotheca buxifolia waste seeds was used for the adsorptive removal of a number of selected azo dyes such as Eriochrome Black T (EBT), Remazol brilliant blue (RBB), Remazol yellow (RY) and Remazol brilliant orange (RBO) from an aqueous solution by changing the initial dye concentration, adsorbent dosage, solution pH, contact time and temperature. A Fourier transform infrared spectroscopic analysis of the activated carbon showed the existence of hydroxyls, methyl, methylene, carbonyls, alkane and alkenes groups while the scanning electron microscopic image displayed the gradual formation of cavities and open pores on the surface. The results showed that as the amount of the adsorbent and the shaking time were increased, the removal percentage of the dye increased accordingly. Higher adsorption percentages were observed at a lower dye concentration and temperature in an acidic media at a pH range (1-5). The investigated data were evaluated with the Langmuir and Freundlich adsorption models. The maximum adsorption capacities obtained from the Langmuir model were 112.36, 96.34, 97.65 and 90.91 mg/g for EBT, RBB, RY and RBO, respectively. The results indicated that the electrostatic interaction was the main cause of the adsorption of these anionic azo dyes on the surface of the activated carbon.

A general adsorption model able to provide a good description of the multilayer adsorption of ions and molecular compounds under any circumstances is proposed in this paper. In order to reach this goal, a general form of isotherm was deduced based on the Gapon equation and classical isotherm forms. The adsorption of molecular compounds with diverse hydrophobicity and acid-base characteristics were investigated and validated with a new model for the adsorption of four pesticides on different soils. The adsorption capacity and adsorption energy estimated by the new model were found to be related to the organic matter content of the soil. Great differences were found in the isotherm parameters (A_i, K_i, and n_i) among both the soils and compounds investigated here.

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.

The environment is changing quickly and it is ever more burdened in connection with the greater needs of human society. This fact has increased efforts to improve the management of land and natural resources and the necessity to evaluate them. Land valuations become more important as the land consumption increases. Soil needs to be evaluated in the whole context of how its quality is affected and the values it provides. The concept of ecosystem services offers this holistic view. This paper defines ecosystem services (ES), the various linkages between soil properties, their functions and benefits, the assessment of soil quality using indicators and then briefly mentions EU environmental assessment methods and terms used in the context of ES. The article also mentions frameworks with which to assess and evaluate the soil quality that can be divided into two groups. The first group is comprised of a framework of indicators that describe the current state of the soil system assessment for evaluating the quality of the agricultural land. This is based on a detailed measurement of the terrain, a statistical analysis of soil databases or processing the status of specific threats to the soil. The second group is comprised of a framework of indicators focused on changes in the soil quality and applied soil management. These frameworks deal with the productivity of the soil in various systems of farming, compare agricultural systems or discuss the advantages of soil biota as indicators of soil quality in detail. Many of the designs of the soil quality indicators focus on the soil management in the context of a single discipline such as agriculture or water pollution. There are concepts for considering the soil quality in regional planning.

Salinisation threatens the sustainability of irrigated olive orchards in Tunisia. Electromagnetic induction measurements and soil spectral index calculations could help to survey the soil salinity. This study aimed to map changes in the soil salinity spatial pattern using geostatistical techniques and soil spectral index regression. The study area is located in Sminja, Tunisia. It is a 665 ha olive orchard, landscaped in ridges and furrows and managed following a very high-density planting system (1.5 × 4 m²). Electromagnetic readings measured in situ with an electromagnetic device (EM38) that was fitted, in turn, to the electrical conductivity of the saturated paste of five soil depths namely: 0-20, 20-40, 40-60, 60-80 and 80-100 cm and to the average electrical conductivity of the saturated paste of the 0-100 cm soil depth. Both the ordinary kriging and universal kriging performed similarly and well in mapping the soil salinity. (R²= 0.86 and 0.89 for the 0-20 cm and the 0-100 cm depths, respectively). Our results prove that mapping the soil salinity based on electromagnetic induction and kriging methods is an effective approach, which allows one to monitor the soil salinity within permanent croplands in semi-arid conditions. Salinisation that reaches intolerable values by olive trees, is especially accumulated on the top of the ridges, where the drippers are installed. Furthermore, based on two Landsat 8 images acquired on April 30, 2019 and May 16, 2019, respectively, we calculated seven soil spectral indices. Nevertheless, multiple regression models between the electromagnetic readings and various combinations of soil spectral indices were poor. In the coming investigations, under permanent land cover, spectral index regression models should integrate not only the soil, but also vegetation indices.

In order to increase the reuse of wastes and residues, as required by the Waste Framework Directive, the potential use of waste, residue and natural minerals as low-cost permeable reactive barrier (PRB) materials was investigated. The performance of a kitchen waste compost, sepiolite and steel slag was compared with that of volcanic slag, pumice and activated carbon in removing specific contaminants from landfill leachate. The experiments represented that the activated carbon removed 27% of the ammonium (NH4+), 75% of the chemical oxygen demand (COD) and 100% of the phosphate (PO43-), zinc (Zn2+) and nickel (Ni2+) from the landfill leachate. Volcanic slag exhibited removal efficiencies of 50% COD and 100% PO43- and pumice exhibited removal efficiencies of 20% NH4+, 27% Zn2+, 65% COD and 100% PO43-. The reactive materials were also checked for their potential in releasing unwanted constituents and represented different levels of the solute (e.g., PO43-, SO42-, NH4+) release. Among the reactives, sepiolite was found to be the reactive material reflecting a minor release (e.g., Zn2+, Cd2+ and Ni2+), but also delivering removal efficiencies of 40, 50, 65, 95, 97, 98, 98 and 100% for Ni2+, COD, Zn2+, SO42-, Cl-, F-, NH4+ and PO43-, respectively. The results show that the studied materials have the potential as reactives for PRB systems treating high strength contaminant plumes.

The project dealt with an evaluation of the soil quality in the Central Bohemian Region in the Czech Republic. The relevant attributes and characteristics were found regarding the soils in this selected area. Based on the data from soil probes, climate characteristics, soil production function and data on the land use, the characteristics, known as soil quality indicators, were selected. Then the soils were sorted into groups which indicated their suitability for the best land use and planning. The characteristics of the soils that contributed the most to the ecosystem services provided by this part of the environment were chosen as the soil quality indicators. In order to find out how the soils are able to provide ecosystem services, two types of approaches were used - the average score and the total amount of points gained. Maps indicating the soil quality were created using the ArcGIS program. At the same time, research on the differences in the quality in two different layers of the soil was carried out. In most cases, there was a decrease in the soil quality with an increasing depth. The results of this project can be used as a basis for a new soil valuation in the Czech Republic.

Soil aggregates have great effects on soil properties and soil functions. Mulching (organic inputs) has been known as a factor influencing soil aggregate stability. Our study aimed to reveal the causes of the higher stability of soil aggregates under organic mulches. The primary soil characteristics such as organic carbon (Cox), humus quality (E4/E6), potential wettability index (PWI), and aromaticity index (iAR) were determined. The Cox was measured using rapid dichromate oxidation, and E4/E6 was measured using the UV-Vis spectrophotometry. The PWI and iAR were determined according to the intensity of selected bands in diffuse reflectance infrared spectra. Results showed that mulched plots contained higher Cox content in aggregates in comparison with whole soil. This indicates that the carbon was stabilized within the aggregates and sequestrated into the soil. The iAR was significantly higher after using the organic mulches, the aliphatic components of the organic matter thus contribute more to the aggregates stabilization. The PWI of aggregates was found to be higher after applying these mulches than in soil. Organic mulches are therefore able to reduce the wettability of the aggregates and also to protect the aggregate from dispersion with water.

Soil thermal properties regulate the thermal and water balance and influence the soil temperature distribution. The aim of the current study is to present data on the changes in the thermal properties of Cambisols at different ratios between the water content and the air in the pore space under different vegetation covers in mountain regions. The undisturbed soil samples were taken from the surface soil layers under grassland, deciduous and coniferous forests in three experimental stations of the Forest Research Institute - Gabra in Lozen Mountain, Govedartsi in Rila Mountain and Igralishte in Maleshevska Mountain. The soil thermal conductivity (λ), the thermal diffusivity (α) and the volumetric heat capacity (C_v) were measured with the SH-1 sensor of a KD2Pro device at different matric potentials in laboratory conditions. The thermal conductivity of the investigated soils was also measured with the TR-1 sensor of a KD2Pro device at the transitory soil moisture in field conditions. An increase in the thermal properties with the soil water content was best pronounced for λ and depended inversely on the total porosity. As the total porosity increased with the soil organic carbon content and decreased with the skeleton content, the lowest value of λ was established in the surface horizons of Dystric Cambisols (Humic) in the experimental station in Govedartsi. The soil thermal conductivity increased with the depth under the deciduous forest (Gabra and Igralishte) due to the lower soil organic carbon content (SOC) and the total porosity. There were no such changes in the subsurface horizon under the grassed associations. The increase in the heat capacity with the water content depended on the SOC to less extent. In the horizons with a SOC of less than 1.5%, the changes in the thermal diffusivity over the whole range of wetness were 1.7 times higher than those with a higher SOC.

The widespread hillslope- and gully-erosion in Liaoning Province of Northeast China, pose serious challenges to the local agricultural production. Hillslope- and gully-erosion have typically been studied separately; however, there has been little investigation on the relationship of these two types of erosion. In this study, the coupling relationship of the hillslope- and gully-erosion from the perspectives of erosion intensity and land use, as well as the slope gradient, aspect, and shape, was analysed. The study employed remote sensing and geographic information system techniques, and the universal soil loss equation and kriging were used to perform a macroscopic analysis. The results showed that gully-erosion was more severe compared with hillslope-erosion in the study area. The cultivated land has the highest level of human activities, therefore, the most intense hillslope- and gully-erosion. The threshold slope gradients for the hillslope- and gully-erosion are 14° and 6°, respectively. Above the threshold of 6°, the slope gradient is no longer the primary factor affecting the gully-erosion. Sunny slopes have observably more hillslope-erosion than shady slopes, and the highest hillslope-erosion is observed on the south-southeast-facing slopes. The effect of the slope aspect on the gully-erosion should not be ignored, as evidenced by the considerable gully density of the east-northeast-facing slopes which is obviously higher than for slopes with other slope aspects. The highest hillslope-erosion amount and gully density occur on concave slopes, followed by convex and straight slopes, and straight slopes have little effect on the hillslope-erosion, but have a marked impact on the gully-erosion. The results of this work may serve as a scientific reference for the comprehensive control of soil erosion across a slope-gully system in Northeast China.

Land degradation caused by erosion processes is a widespread global problem. Rain simulators are one of the tools often used to determine the resistance of soils to erosion processes. The aim of this publication is to present the process of the construction and calibration of a small, portable field simulator which would be implemented in research studies designed to determine the changes in the soils' shear strength parameters in forested areas (in situ) caused by a change in soil moisture content achieved by the rain simulation. The constructed simulator consists of a metal frame, sprayers (with specific nozzles), a sediment funnel/tray made of metal, water and a sediment collector unit, a water tank and pump, and a set of rubber hoses, manometer, valves, reducers, adapters and other supplementary equipment. The calibration was carried out by using the pluviometric method. The choice of nozzles was based on the criteria of low water consumption (losses), the Christiansen uniformity coefficient (CU) and the possibility of achieving specific downpour intensities for the investigated area. The further calibration of the device consisted of determining the raindrop diameter and the distribution of the rainfall when the simulator is positioned on the slopes (7° and 15°). The achieved rain intensity was 1.7-1.9 mm/min, with a CU of 92.23-93.70% for the raindrop diameters (D₅₀) equal to 1.2 mm. The kinetic energy of the simulated rain (Ke) was 2.82∙10^-6 J. The constructed simulator proved itself to be in accordance with all of the given criteria, and it can successfully be implemented in research studies aimed at determining the resistance of forest soils to erosion processes, infiltration, and sediment yield.

Preferential flow is associated with potential issues of poor irrigation water-fertiliser efficiency in a cultivated field. In addition, a preliminary understanding of how irrigation quotas contribute to this prevalent phenomenon is limited. Thus, one blank control group and three different irrigation quotas were set (0, 450, 550 and 650 mm) and the dye tracing image method was applied to investigate the characteristics of the preferential flow in cotton fields under mulched drip irrigation. On the basis of the results, we found significant differences in the preferential flow degree between the four groups (P = 0.02); the mean scores of the dyed area ratio D_c and variation coefficient C_v from the soil stained profile were 29.83%, 45.77%, 37.36%, 39.40% and 0.98, 1.12, 1.28, 1.17 for the total irrigation quota 0, 450, 550 and 650 mm, respectively, indicating an increasing and then decreasing tendency for the non-uniformity as well as variation in the soil water flowing as the irrigation quota being put on. At the same time, the preferential flow ratios showed a similar trend compared with D_c as well as C_v, which were 4.64%, 13.70%, 40.03%, and 23.60% for the irrigation amounts of 0, 450, 550, and 650 mm, respectively. In general, we concluded that the degree of preferential flow with an irrigation quota of 550 mm (local irrigation practice) was highest while no irrigation led to a more uniform flow in the cotton fields with film mulched. The present study goes some way towards supplementing our understanding of preferential flow in agricultural practice.

With the surrounding environment of Inner Mongolia lead (Pb) ore as the research background, the germination and physio-biochemical effects of Pb stress on alfalfa were discussed to employ this species for the remediation of Pb contaminated soil. Research has shown that a low Pb stress concentration could improve the biological resistance of alfalfa seeds, while a high Pb stress concentration cannot be tolerated. Interestingly, when the Pb concentration was 5 mg/L, the germination rate of the seed was promoted, and the chlorophyll content was especially increased. As the Pb content and stress increased, the amount of malondialdehyde (MDA), H2O2, catalase (CAT) increased; while the root cell viability, chlorophyll and soluble protein content decreased. In consequence, alfalfa was tolerant to Pb stress of 5 mg/L, inversely, its growth was inhibited at levels higher than 5 mg/L, and it was poisoned at 500 mg/L. Based on the principal component analysis (PCA), the H2O2, O2-, chlorophyll total, chlorophyll a, CAT and proline content explicitly reflected the change in the physiology on the alfalfa and its tolerance under Pb stress.

Several experimental methods have been developed to fractionate soil organic carbon (SOC) into functional sub-pools. However, which fractions had the potential to better reflect the SOC dynamics responding to fertilisation are still under discussion. Thus, we compared different SOC fractions (microbial biomass carbon, MBC; dissolved organic carbon, DOC; permanganate-oxidisable carbon, POXC; particle organic carbon, POC, and aggregation organic carbon fractions) and the soil respiration rate in a wheat-corn rotation field after 40 years of manure and N fertilisation in North China to search for the most sensitive SOC fractions to fertilisation. Manure increased the organic carbon (OC) contents of all the soil fractions (26.5 to 362.8%) and the POC (18.0 to 43.7%) and macro-aggregation percentages (3.0 to 4.4%), which indicated an increasing physical-protected aggregated OC fraction. N fertilisation alone slightly increased the OC contents of all the soil fractions and DOC percentage, but decreased the macro-aggregation OC percentage, which suggests the increasing possibility that the SOC is exposed to microbial communities causing a decreasing aggregation formation. However, when a high level of both the manure and N fertiliser were applied, the excessive N in the soil stimulates the soil microbial activity and decreases the SOC content comparing it to the same level of the manure fertiliser addition.

An attempt was made to ascertain the environmental effects of animal wastes pollution on agricultural soil and water quality at the oldest teaching and research farm, Federal University of Technology, Akure, Nigeria. Physical, chemical, and bacteriological analyses of water (shallow well) and soil samples were carried out to determine the present quality status. Fifteen soil samples collected at the centre of the animal wastes dump and at a distance of 5 and 10 m, and three different samplings done on the water source were analyzed. The parameters determined using APHA standard procedures included: turbidity, temperature, pH, alkalinity, sulphide, phosphate, dissolved oxygen, total dissolved solids, total hardness, biochemical oxygen demand, total iron, nitrate, chloride, calcium, and heavy metals like copper, zinc, and lead. Most of the parameters indicated pollution including heavy metals presence with the exception of Pb, Zn, Mn, Cu, and Cr that were not detected in water samples. Concentrations of nitrate, biochemical oxygen demand, SO₄^2-, PO₄^3-, and Cl^- were 0.20, 3.20, 10.50, 3.5, and 20.4 mg/l respectively, while those of detected heavy metals such as Mg and Ni were 1.98 and 10.03 mg/l, respectively. Soil water holding capacity, porosity, pH, organic matter, organic carbon, and organic nitrogen ranged from 33.34 ± 3.73 to 59.06 ± 5.69, 34.6 ± 3.28 to 52.43 ± 5.5, 6.56 ± 0.03 to 7.54 ± 0.03, 2.32 ± 0.03 to 5.35 ± 0.03, 1.33 ± 0.01 to 3.11 ± 0.01, and 0.58 ± 0.07 to 1.13 ± 0.03%, respectively. The results showed that the well is strongly polluted with bacteria and pathogens and requires considerable treatment before use while the soil is suitable for crop production.

The aim of this study was to evaluate the response pattern of diazotrophic microbes, denitrifiers and nitrifiers to different types of land use management, such as soybean monoculture (M) during 5 and 24 years (M5 and M24) and soybean-maize rotation (R) during 4 and 15 years (R4 and R15) in two subsequent years at the time point of flowering. Soil samples from a site recently introduced into agriculture (RUA) and a pristine soil under native vegetation (NV) were used as controls. Abundances of different functional groups of microbes were assessed using the direct quantification of marker genes by quantitative real-time PCR using extracted DNA from rhizosphere samples. In addition, soil chemical and physical properties were analysed and correlated with the abundance data from the functional microbial groups under investigation. Overall, the results indicate that the abundance of nifH genes was higher under R treatments compared to M treatments. The abundance of ammonium monooxygenase genes amoA (AOA) was generally higher under rotation systems and decreased under M24. RUA evidenced a negative effect on the establishment and development of AOA communities. The influence of land use on nirS abundance was inconsistent. However, R treatments showed a high abundance of nirK genes compared to M treatments. In both growing seasons, the abundance of nosZ genes was higher under NV compared with the other treatments. Furthermore, M24 treatment was related to strongly changed chemical and physical soil properties compared with the other sites. As expected, soil samples from RUA showed the strong dynamics of measured parameters indicating the high sensitivity of soils under transition to environmental parameters. Our results also indicated that the long-term crop rotation modified the abundance of the investigated microbial groups compared to the monoculture and increased soil chemical and physical quality. Therefore, our results provide evidence for a stimulatory effect of the long-term crop rotation on the abundance of microbes involved in N transformation.

One of the most significant environmental problems in Europe is the land use change as a result of urbanization. The estimate of future agricultural land takes in the Czech Republic previously published in this journal is alarming; however, this is based on arbitrarily determined assumptions. Our contribution brings a more realistic assessment of the extent of expected land takes (example of the Hradec Králové Region). For this purpose, the data from the municipalities' Planning Analytical Materials (PAM) on buildable areas (and redevelopment areas) and data on the existing expansion of built-up areas are used. Particular attention is paid to the best quality soils included in the 1^st and 2^nd protection class of agricultural land resources (ALR), because some municipalities located in fertile agricultural areas argue about the necessity to build up good-quality land. The Pearson correlation coefficient has been used for the evaluation to what extent the share of the soils included in the 1^st and 2^nd protection classes of ALR out of the total area of the municipality is really related to the share of best quality soils in planned buildable areas. The spatial statistics method ‒ geographically weighted regression (GWR) has been used to find spatial deviations from the global relationship model. There is a clear differentiation between the municipalities as to whether they are able to rather protect the best soil or whether they are planning future construction predominantly on it. E.g. in municipalities with about 30-50% of the land included in the 1^st and 2^nd ALR protection classes, buildable and redevelopment areas are designed from 0 to 100% for these highest classes of ALR protection. However, the total strength of the association (Pearson's r) between these indicators is large, r = 0.80 (or r = 0.95 when "the point-index value of agricultural land" was used instead of ALR protection classes). The results of GWR show that higher deviations from the model value, both positive and negative ones, are not spatially clustered but located next to each other. Greater deviations occur more frequently in the more fertile western part of the region, where there is a higher pressure on good-quality land, which is either intended for development or protected on the basis of local factors (including spatial planning of individual municipalities). Estimation of future developments has revealed a substantial over-dimensionality of planned buildable areas - they will potentially be built up in more than 100 years.

Soil aggregate structure and soil organic matter are closely interrelated and commonly considered as key indicators of soil quality. The aim of this study was to evaluate the effects of different fallow durations on indices of soil structure and humus status indicators. Studies were conducted on abandoned agricultural fields (15, 20 and, 35 years after abandonment). As a reference site, we used a cultivated field in the area. The experimental soil fields are classified as Gleyic Cambisols. Soil macroaggregates were separated with the sieve (dry sieve) to seven aggregate size fractions, i.e.> 10, 10-5, 5-2, 2-1, 1-0.5, 0.5-0.25 and < 0.25 mm. The humus status parameters of soils included the following indicators: soil organic carbon (C_org), humus reserves (Q_H), the degree of humification of organic matter (SOM_dh), fractions of humic acids (HA) (free and bound with monovalent cations and Al₂O₃, Fe₂O₃, bound with Cа²⁺ which forms humates, bound with clay minerals), fulvic acids (FA) (free aggressive) and ratio of HA to FA (C_HA : C_FA). After a fallow period of more than 20 years on the surface formation of a sod layer. A long-term fallow period had an impact on the mean weight diameter of the aggregates (MWD) and agronomically valuable aggregates (AVA). Fallow soils have a significantly better structure than soils under a cultivated field. Long-term cultivation leads to the deterioration of soil structure and the formation of large aggregates (>10 mm). The C_org content remains at the level of the background content when the soils are left fallow for less than 15 years and increases over time. The C_org in the upper 0-20 cm soil layer has been shown to increase from 3.55 to 8.74% on arable land that has been fallow for 35 years and has been largely associated with significant accumulation of organic matter within the plant root mass. Mature sites are characterized by an increase of fulvic acids in the humus composition in comparison with their arable analogues. The abandonment of soil agricultural use and the cessation of mechanical tillage results in the restoration of the natural structure of soils and the improvement of their agrophysical properties. Such studies have not been previously conducted in the Primorsky region of the Russian Far East.