Search Results (32)

High levels of pesticide use are associated with intensive crop production. Pesticides are increasingly prevalent in surface and groundwater, which is a major environmental concern. Various methods have been proposed to improve the retention and/or degradation of pesticides in soils. These methods are mainly based on soil adaptation with organic wastes to mitigate soil and water pollution. In addition, there has recently been increased interest in assessing the influence of organic waste additions on pesticide movement in soils with low contents of organic matter. Agriculture and related industries generate large amounts of waste each year. Because of their components, they have the great ability to produce high-value products for environmental restoration. This study reports on the influence of four different agro-industrial wastes (orange peel, beer bagasse, grape pomace, and gazpacho waste) used as organic amendments on the leaching of metobromuron and chlorbromuron (phenylurea herbicides) on a silty clay loam soil (gypsic–calcaric regosol) with low organic matter contents from a semiarid area (southeastern Spain). The adsorption, leaching, and dissipation processes of these herbicides were evaluated on a laboratory scale in amended and unamended soils. In addition, the main leaching indices (GUS, LIX, LEACH, M LEACH, LIN, GLI, HI, and ELI) commonly used to assess groundwater protection against pesticide pollution were evaluated. The sorption coefficients (K_OC) increased in the amended soils. Metobromuron was found in leachates in all cases, although a marked reduction was observed in amended soils, while chlorbromuron was mainly retained in soils, especially in the top layer. The disappearance time (DT₅₀) for metobromuron and chlorbromuron in soil ranged from 11 to 56 d and 18 to 95 d, respectively. All indices except GLI categorize metobromuron as mobile or very mobile in unamended soil. For chlorbromuron, GUS, LIX, LEACH, MLEACH, and Hornsby classify this compound as a medium-to-high leache, while GLI and ELI classify it as having low mobility. In amended soils, most indices classify metobromuron as transitioning to mobile, while most indices catalog chlorbromuron as immobile/transition. Full article

The effects of climate change are particularly pronounced in cities, where urban green infrastructure—such as trees, parks, and green spaces—plays a vital role in both climate adaptation and mitigation. This study assesses the carbon sequestration potential of urban forests in Budapest, the capital city of Hungary, which lies at the intersection of the Great Hungarian Plain and the Buda Hills, and is traversed by the Danube River. The city is characterized by a temperate climate with hot summers and cold winters, and a diverse range of soil types, including shallow Leptosols and Cambisols in the limestone and dolomite hills of Buda, well-developed Luvisols and Regosols in the valleys, Fluvisols and Arenosols in the flood-affected areas of Pest, and Technosols found on both sides of the city. The assessment utilizes data from the National Forestry Database and the Copernicus Land Monitoring Service High Resolution Layer Tree Cover Density. The results show that Budapest’s urban forests and trees contribute an estimated annual carbon offset of −41,338 tCO₂, approximately 1% of the city’s total emissions. The urban forests on the Buda and Pest sides of the city exhibit notable differences in carbon sequestration and storage, age class structure, tree species composition, and naturalness. On the Buda side, older semi-natural forests dominated by native species primarily act as in situ carbon reservoirs, with limited additional sequestration capacity due to their older age, slower growth, and longer rotation periods. In contrast, the Pest-side forests, which are primarily extensively managed introduced forests and tree plantations, contain a higher proportion of non-native species such as black locust (Robinia pseudoacacia) and hybrid poplars (Populus × euramericana). Despite harsher climatic conditions, Pest-side forests perform better in carbon sink capacity compared to those on the Buda side, as they are younger, with lower carbon stocks but higher sequestration rates. Our findings provide valuable insights for the development of climate-resilient urban forestry and planning strategies, emphasizing the importance of enhancing the long-term carbon sequestration potential of urban forests. Full article

Water quality affects soils by promoting their degradation by the accumulation of salts that will lead to salinization and sodification. However, the magnitude of these processes varies with soil attributes. Saturated hydraulic conductivity (K_sat) is the rate at which water passes through saturated soil, which is fundamental to determining water movement through the soil profile. The K_sat may differ from soil to soil according to the sodium adsorption ratio (SAR), water electrical conductivity (EC_w), soil texture, and clay mineralogical assemblage. In this study, an experiment with vertical columns and constant-load permeameters was conducted to evaluate changes in soil K_sat with waters comprising five EC_w values (128, 718, 1709, 2865, and 4671 µS cm⁻¹) and five SAR values [0, 5, 12, 20, and 30 (mmol_c L⁻¹)^0.5] in combination. Horizons from nine northeastern Brazilian soils (ranging from tropical to semiarid) were selected according to their texture and clay mineralogical composition. The data obtained were fit with multiple regression equations for K_sat as a function of EC_w and SAR. This study also determined the null SAR at each EC_w level, using K_sat = 0 on each equation, to predict the SAR needed to achieve zero drainage on each soil for each EC_w level and the threshold electrolyte concentration (C_TH) that would lead to a 20% reduction of maximum K_sat. Neither the EC_w nor SAR of the applied waters affected the K_sat of soils with a mineralogical assemblage of oxides and kaolinite such as Ferralsol, Nitisol, and Lixisol, with an average K_sat of 2.75, 6.06, and 3.33 cm h⁻¹, respectively. In smectite- and illite-rich soils, the K_sat increased with higher EC_w levels and decreased with higher SAR levels, especially comparing the soil’s estimated K_sat for water with low EC_w and high SAR in combination (EC_w of 128 µS cm⁻¹ and SAR 30) and water with high EC_w and low SAR in combination (EC_w of 4671 µS cm⁻¹ and SAR 0) such as Regosol (4.95 to 10.94 cm h⁻¹); Vertisol (0.28 to 2.04 cm h⁻¹); Planosol (0 to 0.29 cm h⁻¹); Luvisol (0.46 to 2.12 cm h⁻¹); Cambisol (0 to 0.23 cm h⁻¹); and Fluvisol (1.87 to 3.34 cm h⁻¹). The C_TH was easily reached in soils with high concentrations of highly active clays such as smectites. In sandy soils, the target C_TH was only reached under extremely high SAR values, indicating a greater resistance of these soils to salinization/sodification. Due to their mineralogical assemblage, soils from tropical sub-humid/hot and semiarid climates were more affected by treatments than soils from tropical humid/hot climates, indicating serious risks of physical and chemical degradation. The results showed the importance of monitoring water quality for irrigation, mainly in less weathered, more clayey soils, with high clay activity to minimize the rate of salt accumulation in soils of the Brazilian semiarid region. Our study also proved that clay mineralogy had more influence on the K_sat than clay concentration, mainly in soils irrigated with saline and sodic waters, and that soils with highly active smectite are more prone to degradation than soils with high concentrations of kaolinite. Full article

Sustainable soil management through the use of an appropriate tillage system can positively change the edaphic parameters. The aim of the present study was to compare the effects that reduced tillage (RT) and conventional tillage (CT) systems have on changes in selected physical and chemical properties and enzymatic activity in various soil types. The study included the following soil types: Eutric Fluvisol, Mollic Fluvisol, Haplic Chernozem, Haplic Luvisol, Eutric Regosol, Eutric Gleysol, and Stagnic Planosol. Soil samples were collected in the Danubian Lowland and Eastern Slovak Lowland. The following parameters were determined in the soil samples: soil texture, pH, hydrolytic acidity and the sum of basic exchangeable cations, the contents of carbon (TOC), nitrogen (TN), and dissolved organic carbon (DOC), and the activities of dehydrogenases (DEH), catalase (CAT), peroxidases (PER), alkaline phosphatase (AlP), acid phosphatase (AcP), proteases, and β-glucosidase (BG). The reaction of the analysed soils, in the RT and CT cultivations alike, ranged from acidic to neutral, and the sorption properties differed between individual soil types. The TOC ranged from 16.53 to 42.07 g kg⁻¹ for conventional cultivation and from 15.51 to 38.90 g kg⁻¹ for reduced tillage. The values of enzymatic soil quality indices values correlated with TOC, DOC, and TN, as well as with pH, the sum of exchangeable base cations, cation exchange capacity, and degree of base saturation of the sorption complex. The tillage system determined changes in the activity of the studied enzymes, but the intensity and direction of these changes depended on the soil type. Based on the enzyme activity results, soil quality indices such as GMea and TEI were calculated. TEI proved to be a more sensitive indicator than GMea. It was shown that, of all studied soil types and regardless of the cultivation system, Eutric Gleyosols had the most variable properties. For conventional tillage, Haplic Luvisol and Eutric Regosol were characterised by the greatest uniformity. In general, the edaphic properties of soils under conventional tillage differed from those of soils under simplified tillage. Full article

Groundwater availability in semi-arid regions like the Widyan Basin, the Kingdom of Saudi Arabia (KSA), is a critical challenge due to climatic, topographic, and hydrological variations. The accurate identification of groundwater zones is essential for sustainable development. Therefore, this study combines remote-sensing datasets (Sentinel-2 and ASTER-DEM) with conventional data using Geographic Information System (GIS) and analytical hierarchy process (AHP) techniques to delineate groundwater potential zones (GWPZs). The basin’s geology includes Pre-Cambrian rock units of the Arabian Shield in the southwest and Cambrian–Ordovician units in the northeast, with the Saq Formation serving as the main groundwater aquifer. Six soil types were identified: Haplic and Calcic Yermosols, Calcaric Regosols, Cambic Arenosols, Orthic Solonchaks, and Lithosols. The topography varies from steep areas in the southwest and northwest to nearly flat terrain in the northeast. Hydrologically, the basin is divided into 28 sub-basins with four stream orders. Using GIS-based AHP and weighted overlay methods, the GWPZs were mapped, achieving a model consistency ratio of 0.0956. The zones were categorized as excellent (15.21%), good (40.85%), fair (43.94%), and poor (0%). The GWPZ model was validated by analyzing data from 48 water wells distributed in the study area. These wells range from fresh water to primary saline water, with water depths varying between 13.98 and 130 m. Nine wells—with an average total dissolved solids (TDS) value of 597.2 mg/L—fall within the excellent zone, twenty-one wells are categorized in the good zone, fifteen wells are classified in the fair zone, and the remaining wells fall into the poor zone, with TDS values reaching up to 2177 mg/L. The results indicate that the central zone of the study area is suitable for drilling new water wells. Full article

Elevated carbon dioxide (eCO₂) levels can enhance crop yields but may simultaneously reduce quality, impacting both macronutrient and micronutrient concentrations, and potentially decreasing protein content in cereal grains. This study examined the effects of elevated CO₂ (eCO₂) and nitrogen (N) fertilization on crop growth, yield, and soil nitrogen cycling through a glass greenhouse experiment using Eutric Regosol soil. The experimental design incorporated two CO₂ gradients: ambient CO₂ (aCO₂) at approximately 410 ppm during the day and 460 ppm at night, and eCO₂ at approximately 550 ppm during the day and 610 ppm at night. Additionally, two nitrogen fertilization treatments were applied: no fertilizer (N0) and 100 mg N kg⁻¹ dry weight (DW) soil (N100). Crops were cultivated under two cropping systems: the monoculturing of fababean (Vicia faba L.) or wheat (Triticum aestivum Yunmai) and the intercropping of both species. The results demonstrated that eCO₂ significantly enhanced the growth and yield of both fababean and wheat, particularly when nitrogen fertilization was applied. Nitrogen fertilizer application did not always enhance crop yield, considering the complexity of nitrogen management under elevated CO₂ conditions. Furthermore, the intercropping of fababean and wheat presented multiple advantages, including improved crop yields, enhanced soil health, and increased ecosystem services. These findings suggest that intercropping can serve as a sustainable strategy to boost productivity and ecosystem resilience in the face of climate change. The changes in nitrogen application and CO₂ concentration affect the gene copy number of ammonia-oxidizing bacteria and archaea, which may affect the nitrogen cycling process in soil. There are complex interactions between crop biomass, nitrogen accumulation, transpiration rate, photosynthetic rate and stomatal conductance with soil properties (e.g., pH, organic matter, nitrogen content) and microbial community structure. The interaction between CO₂ concentration, nitrogen application level and crop intercropping pattern had significant effects on crop growth, soil properties and microbial communities. Future research should prioritize investigating the long-term effects of intercropping on soil productivity and the development of management strategies that optimize the benefits of this cropping system. Full article

An investigation into the spatial–temporal distribution characteristics of ancient settlements and their relationship with the environment in the Sichuan Basin can enhance our understanding of the evolution of the regional human–land relationship. Utilizing kernel density analysis by GIS, this paper obtained the spatial distribution characteristics of 1100 settlements in the Neolithic, Shang–Zhou, and Qin to Southern Dynasties periods. Subsequently, a GIS spatial analysis was performed to examine the distribution of these settlements in relation to the natural environment, focusing on four aspects: elevation, slope, aspect, and water buffer zone. The results demonstrate that: (1) The distribution of settlements from the Neolithic to the Southern Dynasties has expanded from the Chengdu Plain in the west and the Xiajiang Area in the east to the hilly areas in the center. (2) The settlements in the Neolithic and Shang–Zhou periods are predominantly located at elevations between 300–600 m, slopes between 0–3°, aspects between 135–225°, distances to rivers between 0–1000 m, and soil choice on Luvisols, Cambisols, Regosols, and Anthrosols. The influence of aspect on settlements during the Qin–Southern Dynasties period was notably reduced. The settlements mainly grow in the Chengdu Plain and the smaller plains along the river from the Neolithic to the Southern Dynasties in the Sichuan Basin. (3) The emergence and advancement of primitive agriculture, the construction of early water conservancy facilities, commercial and trade exchanges, and the establishment of regimes led to a shift from a double core to a more dispersed distribution in the Sichuan Basin from the Neolithic to the Southern Dynasties periods. The evolution of settlements reflects the adaption and competition of the residents to the natural environment in the Sichuan Basin. Furthermore, it provides insights into the complex social development in the region, ranging from the formation of early states to the establishment of the Qin and Han Empires. Full article

The independent effects of hedgerow or grass ditches on the migration of runoff, sediment and nutrients are well known; however, the effects of combined hedgerow–grass ditch systems have rarely been assessed. Vegetation stem diameter (VSD) is an essential variable that changes the effectiveness of a hedgerow–grass ditch system in reducing runoff and sediment yield on sloping lands. A hedgerow–grass ditch system was simulated to interpret the effects of varied VSDs [i.e., 0 (control), 0.1, 0.2, 0.4 and 0.8 cm] in hedgerow on runoff and sediment yield by laboratory rainfall simulation. Compared to the control, the time to runoff initiation presented a 43.3% delay in 0.8 cm VSD (p < 0.05), and the runoff rate was significantly reduced by 16.6% in the 0.2 cm VSD and by 17.0% in the 0.8 cm VSD, respectively (p < 0.05). The sediment yield rate decreased by 74.2% and 85.8% relative to that of the control, respectively (p < 0.05). The reduction was 5.3–17.0% for the runoff rate and 3.5–85.8% for the sediment yield rate with varied VSDs relative to the control. The sediment yield rate decreased remarkably as an exponential function with increased stem diameter (p < 0.05). Our results have great significance for creating strategies for soil and water conservation on sloping lands. Full article

The main aim of this study was to assess the amount of carbon (C) stored in the upper 30 cm layer of mineral soils in eucalypt plantations in Portugal, with a Mediterranean-type climate. Soil sampling data (2468 samples), field evaluations (soil profile description) and relevant information on the particle size distribution, climate, bedrock and reference soil group were accomplished. Bulk density per sample was assessed using pedo-transfer functions and soil C stock was estimated. The results showed an average of 41.2 t C ha⁻¹ stored in the soil. In the northern regions of Portugal, the coldest and wettest areas of the country with better stand productivity, a higher soil organic carbon (SOC) is achieved (median SOC of 39.2 g kg⁻¹ and soil C stock of 55 t ha⁻¹) than in southern and inland regions, with a warmer and drier climate (median SOC of 15.2 g kg⁻¹ and soil C stock of 28 t ha⁻¹). The assessment of mean soil C stock per bedrock type revealed higher C stored in granites followed by conglomerates, coal shales and clay shales. Regarding soil type, the results showed a higher C stock in Cambisols, Leptosols and Fluvisols (>50 t C ha⁻¹), whereas Regosols and Luvisols stored less, following the same trend presented for reference soil groups in Europe. Comparing the geographic distribution of the C stock in the upper layer of the mineral soils with the amount of C in eucalyptus stands (root and aboveground biomass—data from national forest inventory), the mineral soil pool can represent more than two-thirds of the total C stored in eucalyptus plantations in Portugal. Further studies should focus on the evolution of C stocks in eucalypt plantations during different stages of stand growth and under different management practices. Full article

Honey contains a wide range of inorganic substances. Their content can be influenced, i.e., by the type of soil on which the bee pasture is located. As part of this study, the mineral profile of 32 samples of honey from hobby beekeepers from the Czech Republic wasevaluated and then compared with soil types in the vicinity of the beehive location. Pearson’s correlation coefficient was used to express the relationship between mineral substances and soil type. There was a high correlation between antroposol and Zn (R = 0.98), Pb (R = 0.96), then between ranker and Mn (0.95), then regosol and Al (R = 0.97) (p < 0.05). A high negative correlation was found between regosol and Mg (R = −0.97), Cr (R = −0.98) and between redzinas and Al (R = −0.97) (p < 0.05). Both positive and negative high correlations were confirmed for phaeozem. The CART method subsequently proved that the characteristic elements for individual soil types are B, Ca, Mg, Ni, and Mn. The soil types of cambisol, fluvisol, gleysol, anthrosol, and kastanozem had the closest relationship with the elements mentioned, and it can therefore be assumed that their occurrence indicates the presence of these soil types within the range of beehive location. Full article

Water majorly contributes to soil erosion. Considering Japan’s humid and rainy climate, severe soil erosion challenges persist even though forests are the country’s dominant land type. Although numerous studies have emphasized the impact of factors such as land use, soil type, and slope steepness on sediment yield, the synergetic effects of slope gradient with varying land cover and soil types are underexplored. Herein, we used the Soil and Water Assessment Tool (SWAT) on a steep catchment to identify high sediment yield areas—as well as factors influencing high sediment yield—and evaluate the effect of slope gradient on the sediment yield of different land cover and soil types. The findings reveal an average annual sediment yield of 0.55 tons ha⁻¹ yr⁻¹ in the Takahashi catchment, with yields tripling in some western subbasins under heavy rainfall. Furthermore, the slope gradient effect is most considerable in bare land, agriculture, and rice land cover, with the average sediment yield of bare land resulting in 2.2 tons ha⁻¹ yr⁻¹ at slope > 45%. Meanwhile, deciduous forests on steep slopes exhibit extreme sediment yield, peaking at 7.2 tons ha⁻¹ yr⁻¹ at slope > 45%. The regosol soil type has one of the highest sediment yield variations in all soil types due to slope gradient. Full article

The soils of the high-elevation mountains along the East African Rift Valley are poorly understood. Assessing the potential of soils for agriculture, climate change mitigation, and environmental functioning requires insight into how they relate to the factors influencing soil formation. Between 3000 and 4120 m a.s.l., 85 soil profiles of Mount Guna were described and sampled. Standard physicochemical analyses were done on all pedons. Additionally, X-ray diffraction, Al_ox and Fe_ox content, and P fixation were performed on six selected profiles. Soils on Mount Guna included Andosols, Phaeozems, Leptosols, Regosols, Cambisols, Luvisols, and Vertisols. With increasing elevation, clay content, bulk density, and pH decreased while the C:N ratio remained constant. In contrast, sand, silt, silt-to-clay ratio, SOC, Ntotal, and SOCS increased. With a factor analysis, the soil-forming factors’ elevation/climate could be disentangled from the factor’s parent material as these affect topsoil and subsoil differently. In the ordination based on climate/elevation and parent material, Andosols and Vertisols stood out while other Reference Soil Groups (RSG) showed indistinct patterns. Soil erosion appeared as an additional soil-forming factor not accounted for by the factor analysis. The distribution of the RSG was significantly associated with elevation belts (p < 0.001), lithology (p < 0.001), and landcover (p < 0.003). On the summital ridge, the Andosols were crucial for groundwater storage due to high precipitation. Shallow and stony soils in the mid-elevation belt contributed to runoff generation. Average soil carbon stock ranged from 8.1 to 11 kg C m⁻² in the topsoil and from 29.2 to 31.9 kg C m⁻² in the upper meter, emphasizing the global importance of high-elevation areas for carbon sequestration. Full article

A fundamental requirement for the effective prevention and management of soil contamination involves the determination of heavy metal contamination levels and the assessment of associated health risks for human populations. In this study, an analysis was conducted to evaluate the pollution levels and health risks associated with heavy metals in urban soils, specifically focusing on four distinct soil types, namely Calcisols, Cambisols, Fluvisols, and Regosols. The mean values of five heavy metals (Zn, Cu, Cd, Pb, and Ni), some soil pollution indices, and human health risk indices were determined. Pollution indices including the integrated Newerow pollution index (PIN), single pollution index (PI), and pollution load index (PLI) showed a moderate pollution class in most soil samples. The non-carcinogen risk index of elements (HI) in each exposure pathway and the total of the exposure pathways (THI) was <1 for three different population groups (children, adult females, and adult males) and in all soils. This shows the lack of non-cancerous risk for local residents in the study site. The variations in HI and THI for the three population groups and three different exposure pathways was in the order of adult males > adult females > children and ingestion > dermal contact > inhalation. The carcinogenicity risk (CR) of Cd, Pb, and Ni through exposure by ingestion was >1 × 10⁻⁴ for children in all soils, meaning that soil ingestion is hazardous to children in the study region. For all three population groups and all soil types, Pb was most effective in HI and THI, whereas Cd had the highest carcinogenicity potential. Full article

Soil structure (SS) plays an important role in relation to climatic change, with the most important task the decreasing of CO₂ in the atmosphere by carbon sequestration in the soil and the prevention of floods by better water infiltration into the soil. However, the evaluation of its condition is very different because of the various parameters and their inappropriate uses. The aim of this study was to determine the responses of the parameters of SS on the soil type and tillage system as the most important factors that influence it through changes in the soil organic matter and soil texture. The soil factor, which was represented by seven soil types (EF, Eutric Fluvisol; MF, Mollic Fluvisol; HC, Haplic Chernozem; HL, Haplic Luvisol; ER, Eutric Regosol; EG, Eutric Gleysol; DS, Distric Stagnosol), should be included in all evaluations of SS because of the specifics of each soil type. The tillage factor (shallow non-inversion-reduced, RT; deeper with inversion-conventional, CT) was chosen because of a high sensitivity of SS to soil disruption by cultivation, which represents high potential for the mitigation of climate change. The study included 126 sampling places in different parts of Slovakia on real farms (7 soil types × 3 localities × 3 crop rotations × 2 tillage systems × 2 soil depths). The soils were analysed for the aggregate fraction composition, particle size distribution, and parameters of organic carbon. The data of different parameters of SS were calculated and evaluated. The most sensitive parameter of the tested ones was the coefficient of structure (K_st), which manifested up to the level of the fractions of humus substances and indicated a better condition of SS in more productive soils than less productive soils. The coefficient of soil structure vulnerability (K_v) and mean weight diameter in water-resistant macroaggregates (MWD_w) showed a worse condition of SS in the soils, which developed on Neogene sediments. A better condition of SS in RT was predicted particularly by the primary parameters (index of crusting, I_c; critical content of soil organic matter, S_t), and in CT, they were mainly the secondary parameters (K_st; water-resistant of soil aggregates, K_w). Overall, the suitability of the parameters of SS should be evaluated in relation to a specific soil type with its characteristics and should not be used universally. Full article

Urban and peri-urban agriculture is one of the strategies that emerged on the path towards agri-food sustainability in cities. This paper aims at improving the knowledge of the soil properties in a peri-urban area and their agricultural potential to support ecosystems with biodiversity worth conserving. The study area was located in the mid-plain of the Segura River (SE Spain). Arable soil layer samples were collected at 68 points to assess the distribution of organic carbon and to study other indicators of soil quality. A Wilcoxon and Kruskal–Wallis test was conducted to compare between the types of soils present in the area (calcaric Fluvisols and calcaric Regosols) and soil uses (industrial, cultivated and abandoned). Statistical analysis indicates that there are significant differences (at the 0.05 significance level) between Fluvisols and Regosols (p value = 3.65 × 10⁻⁵). Regarding use, the abandoned Fluvisols presented an average value of 9.33 g kg⁻¹ of OC while the Fluvisols that are currently cultivated have a higher average content of OC (11.35 g kg⁻¹). For soils under industrial use, the average OC content is 5.13 g kg⁻¹. Spatial distribution of organic carbon in these soils depends on the type of soil and the human influence on them, including the use. Full article