Soils In Spain Research Articles

Tree performances of eight rootstocks grafted with ‘Šumadinka’ sour cherry

Aim of study: This study was conducted to determine the suitability of seven clonal and one seedling rootstocks for grafting of sour cherry cv. ‘Šumadinka’ trough early tree growth, precocity, productivity and fruit quality. Aim of study: To evaluate the suitability of seven clonal rootstocks and one seedling rootstocks for grafting the sour cherry cv. ‘Šumadinka’ based on early tree development, precocity, productivity and fruit quality. Area of study: A sour cherry orchard in village Prislonica, Serbia, near Čačak city. Material and methods: The sour cherry cultivar ‘Šumadinka’ was grafted onto Colt, MaxMa 14, Krymsk 6, Adara, Cigančica, Gisela 5, Gisela 6 and Myrobalan rootstocks. Standard and validated procedures were used to measure tree growth, productivity (from 2017 to 2020), leaf area, fruit physical properties and fruit chemical composition (from 2019 to 2020). Main results: Significant differences were observed among rootstocks in leaf and petiole dimensions, leaf area, tree vigour, yield, fruit size, soluble solids content, titratable acidity, sugars and vitamin C contents, ripening and sweetness indexes. Trees grafted on Adara exhibited the highest tree vigour, while those on Gisela 6 produced the largest fruit size. On the other hand, Colt trees generally displayed the highest sugar content and sweetness index. Adara also showed improvements in fruit quality characteristics, whereas the properties associated with Myrobalan received the lowest evaluation scores. Research highlights: Adara rootstock demonstrated good adaptability to heavy and acidic soil conditions in Serbia, even though it was originally selected for cherry cultivation in heavy, waterlogged, and calcareous soils in Spain. This adaptability likely contributed to its higher vigour, yield, yield efficiency and good fruit quality.

Paramyrothecium nigrum, causing leaf blight disease on watermelon in Iran

<i>Paramyrothecium nigrum</i>, causing leaf blight disease on watermelon in Iran

Pesticide Residues and Heavy Metals in Vineyard Soils of the Karst and Istria

Pesticide residues and heavy metal concentrations were determined in two depths (0–20 and 20–40 cm) of Chromic Cambisol in 69 vineyards in the Slovenian winegrowing region of the Karst. Similarly, pesticide residues and heavy metal concentrations were also determined in two depths of Calcaric Cambisol in 11 vineyards in the other Slovenian and Croatian winegrowing regions of Istria. The topsoil (0–20 cm) was analysed for the presence of 176 different pesticidal active substances using two multiresidue analytical methods: (a) gas chromatography coupled with mass spectrometry (GC/MS) and (b) liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS). Seven active substances (five fungicides and two insecticides) were detected in the soil samples. Their concentrations were compared with the maximum concentrations observed in the vineyards of the winegrowing regions of France, Italy, and Spain. In addition to pesticides, the soil samples were analysed for the presence of nine heavy metals commonly detected in vineyard soils. The concentrations of arsenic, cadmium, cobalt, chromium, copper, molybdenum, nickel, lead, and zinc were below the critical thresholds set by Slovenian legislation, with the exception of one soil sample in which the Cu concentration exceeded the critical threshold. Compared with the maximum concentrations measured in other vineyard soils in Spain, Italy, and France, the heavy metal concentrations in the vineyard soils of Karst and Istria were lower. Both the heavy metal concentrations and the residual concentrations of pesticidal active substances in the vineyard soils of the Karst and Istria regions were significantly lower than the concentrations that are occasionally discussed in the literature.

Acanthamoeba spp. in public parks’ soils in Spain: presence, distribution and risks

Background and aims: Acanthamoeba spp. is a protozoan that is becoming a public health threat. This parasite has been isolated in stray cats from Madrid (Spain), which could play a role in contaminating urban environments. The aim was to determine the presence/distribution of Acanthamoeba spp. in Alcalá de Henares (a major city in the Madrid Region) to identify potential risks. Methods: 227 topsoil samples were collected in July 2017 across urban parks/green areas (155), industrial (60) and a public garden (12). Following extraction of DNA with FastDNA® Spin, a triplex real-time TaqMan PCR assay was performed to detect Acanthamoeba spp., using established methodologies. Organic matter (OM), pH, electric conductivity (EC) and texture (sand, clay and silt percentages) were also determined in soils. Results: Acanthamoeba spp. was detected in 39 topsoil samples, which suggests a moderate distribution throughout Alcalá. Higher presence in the urban (24) area could be explained by the major presence of urban animals, such as stray cats, in this area. The presence of cysts would have not been affected by the OM, pH or EC, despite variations seen in the levels of OM in the studied soils. In contrast to sand and silt, Acanthamoeba spp. seem to be more present in the areas with lower percentages of clay (13.76 detected vs. 18.38 not detected; p=0.006), association which has also observed within the four sub-areas in which the urban area was divided (p=0.016). Clay has more water holding capacity than sand and silt, so it would have been expected to find Acanthamoeba positively associated with clay, although its lower permeability might affect their survival. Conclusions: The low-moderate distribution of Acanthamoeba spp. detected could highlight a risk for the Alcalá population which should be further investigated as this protozoan can affect immunocompromised/immunocompetent individuals. Key words: Acanthamoeba, urban soils, human risks

Potentially Toxic Trace Elements in the Urban Soils of Santiago de Compostela (Northwestern Spain)

With the objective of increasing information inorganic pollutants in urban soils in Spain, we studied the presence of Cu, Pb, Zn, Ni, Cr, and As in 55 soils in the city of Santiago de Compostela (northwestern Spain). The soils were developed over diverse parent materials (granites, gneiss, schists, and amphibolites) and present different land uses, urban grasslands, urban forests, urban allotment gardens, and peri-urban agricultural soils. Total trace element concentrations, analyzed by XRF of ground samples, were correlated to physicochemical properties of the soils, and the influence of land use, lithology, and location on the degree of pollution was explored. In most soils, trace element concentrations followed the sequence Zn (55–484 mg kg−1) &gt; Pb (20–566 mg kg−1) &gt; Cr (17–277 mg kg−1) &gt; Cu (17–188 mg kg−1) &gt; As (13–205 mg kg−1) &gt; Ni (11–91 mg kg−1). The concentrations were overall higher than regional backgrounds, but not high enough to class the soils as contaminated according to the Spanish regulation. Accordingly, the geoaccumulation index values indicate that most soils present low to moderate pollution levels. Among the elements studied, Cu, Pb, and Zn were correlated between them, with their highest concentrations happening in soils of the green areas in the city center; Cr and Ni concentrations were related to lithology of the parent material, with the highest concentrations in soils developed over amphibolite; finally, As concentrations are higher in two precise points without a clear connection to a known source of pollution.

Low density-microplastics detected in sheep faeces and soil: A case study from the intensive vegetable farming in Southeast Spain

One of the main sources of plastic pollution in agricultural fields is the plastic mulch used by farmers to improve crop production. The plastic mulch is often not removed completely from the fields after harvest. Over time, the plastic mulch that is left of the fields is broken down into smaller particles which are dispersed by the wind or runoff. In the Region of Murcia in Spain, plastic mulch is heavily used for intensive vegetable farming. After harvest, sheep are released into the fields to graze on the vegetable residues. The objective of the study was to assess the plastic contamination in agricultural soil in Spain and the ingestion of plastic by sheep. Therefore, three research questions were established: i) What is the plastic content in agricultural soils where plastic mulch is commonly used? ii) Do livestock ingest the microplastics found in the soil? iii) How much plastic could be transported by the livestock? To answer these questions, we sampled top soils (0–10 cm) from 6 vegetable fields and collected sheep faeces from 5 different herds. The microplastic content was measured using density separation and visual identification. We found ~2 × 103 particles∙kg−1 in the soil and ~103 particles∙kg−1 in the faeces. The data show that plastic particles were present in the soil and that livestock ingested them. After ingesting plastic from one field, the sheep can become a source of microplastic contamination as they graze on other farms or grasslands. The potential transport of microplastics due to a herd of 1000 sheep was estimated to be ~106 particles∙ha−1∙y−1. Further studies should focus on: assessing how much of the plastic found in faeces comes directly from plastic mulching, estimating the plastic degradation in the guts of sheep and understanding the potential effects of these plastic residues on the health of livestock.

Biochar changes the bioavailability and bioefficacy of the allelochemical coumarin in agricultural soils.

Allelochemicals can act as biopesticides or enhance the action of synthetic pesticides. In this work, we assessed the bioavailability of the allelochemical coumarin in soils amended with fresh or field-aged biochars (BCs). The fresh BC from oak wood (Fresh BC) was prepared at 550 °C and was buried for aging in two different places: in a sandy loam soil in Spain for 15 months (Aged BC_1) and a sandy loam soil in USA for six months (Aged BC_2). Sorption experiments showed that all BCs were able to increase the affinity of soil towards coumarin, with the distribution coefficient following the order: unamended soil < Aged BC_2-amended soil < Aged BC_1-amended soil < Fresh BC-amended soil. All biochars ensure greater persistence of coumarin and the effect was more pronounced at high chemical dose (10 mg kg-1 ). Conversely, leaching studies in soil columns revealed that BCs were able to maintain coumarin within the first 5 cm of top-soil with total amount extracted ranging between 17% and 22% for BC-amended soil and <1% for unamended soil. Leaching was only observed when coumarin was added at the highest rate. Likewise, the bioefficacy of coumarin against lettuce was enhanced only at 10 kg ha-1 with BC-amended soil. Biochar application to agricultural soils is a promising tool for the management of natural compounds with potential use as biopesticides, such as coumarin, because it increases sorption, persistence and, in some cases, bioefficacy. The results reveal that this effect still persists with aging of BC in soils.

Composition and chemical properties of the soils of the city of Santiago de Compostela, northwestern Spain

AbstractUrban soils are still insufficiently studied despite the relevance of their functions in the urban environment. The city of Santiago de Compostela (northwestern Spain) offers interesting opportunities for the study of urban soils because of its geological diversity and the variety of land use and vegetation. With the objective of increasing information about urban soils in Spain, we studied samples from 56 urban soils (0–20 cm) in this city, developed over different parent materials (granites, gneiss, schists, and amphibolites) and under several land uses (lawn areas, forested areas, urban allotment gardens, peri‐urban agricultural soils, and a green roof). The main physicochemical properties of the soils were analyzed, including bulk density, texture, pH, organic matter, cation exchange capacity, available P, and compounds of Fe and Al. The soils are coarse textured (dominant texture is sandy loam) and acidic (pH in water from 4.7 to 6.9), with moderate to high organic matter contents (13–137 g organic C kg−1). Cation exchange capacity ranges from 9 to 48 cmolc kg−1, with Ca as the most abundant exchangeable cation in most soils. Overall, the soils do not show several of the common features of other urban soils, such as alkalinity, high bulk density, or large amounts of artifacts, and their composition is very similar to their natural counterparts in the region. The conservation of these soils with a low degree of artificialization is essential because they can provide a wide range of ecosystem services.

Roseovarius ramblicola sp. nov., a moderately halophilic bacterium isolated from saline soil in Spain.

Strain D15T was isolated from a soil sample taken from Rambla Salada (Murcia), south-eastern Spain, by using the dilution-to-extinction method. The strain, a Gram-stain-negative aerobic bacteria, is non-motile, ovoid- or rod-shaped, catalase- and oxidase-positive, and grows at NaCl concentrations within the range 0.5-10 % (w/v) [optimum 3 % (w/v)], at 5-30 °C (optimum 28 °C) and at pH 6-9 (optimum pH 7.0). The 16S rRNA gene sequence indicates that it belongs to the genus Roseovarius in the class Alphaproteobacteria. Its closest relatives are Roseovarius tolerans EL-172T and Roseovarius azorensis SSW084T, to which the strain shows 16S rRNA gene-sequence similarity values of 96.1 and 95.3 %, respectively. The DNA G+C content is 63 mol%. The major fatty acids (>5 % of the total fatty acids) of strain D15T are C18 : 1ω7c, C16 : 0 and C12 : 0. The only detected isoprenoid quinone of strain D15T is ubiquinone 10 (Q-10). The polar lipid profile contains phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, aminolipid and three polar lipids. Based on the phylogenetic, genotypic, phenotypic and chemotaxonomic data, the strain represents a novel species of the genus Roseovarius, for which the name Roseovarius ramblicola sp. nov. is proposed. Strain D15T (=CECT 9424=LMG 30322) is the type strain.

Antimicrobial Resistance Genes in Animal Manure, Manure-Amended and Nonanthropogenically Impacted Soils in Spain

Environmental dissemination of antimicrobial resistance genes may occur through agricultural residues, such as animal manure. We studied the resistome of 16 pool samples of animal manure (pig slurry [n = 8] and poultry manure [n = 8]), and 16 soil samples (manure-amended [n = 8] and nonmanure-amended [n = 8]). All samples were collected in central Spain. Detection was based on 18 selected antimicrobial resistance genes (ARGs). The most commonly detected genes in animal manure were sul1 (16/16), sul2 (16/16), tet(A) (16/16), aadA (16/16), tet(B) (15/16), and str (15/16). Genes blaTEM (7/8), mecA (6/8), vanA (5/8) and qnrB (4/8) were more frequently detected in chicken manure, whereas pig slurry samples presented higher levels of tet(C) (8/8) and tet(M) (8/8). Out of the four genes selected for their clinical relevance, three—blaCTX-M, vanA, and mecA—were detected in animal manure. The blaCTX-M (1/8) and vanA (5/8) genes were only identified in chicken manure. To our knowledge, this is the first report of direct detection of mecA gene in poultry manure and pig slurry. Eleven out of 18 ARGs were detected in amended soil, while only genes sul2 (3/8) and str (2/8) were found in nonanthropogenically impacted soils (NAIS), supporting the hypothesis that ARGs may serve as indicators of “anthropogenic impact” on the environment.

The Potential of Juniperus thurifera to Sequester Carbon in Semi-Arid Forest Soil in Spain

The main purpose of this work is to show the influence of vegetation in the storage and stabilisation of organic carbon in semi-arid Juniperus thurifera (J. thurifera) forest soil in central Spain. The variability of the organic matter storage with factors such as sex, trunk diameter and the protection of the canopy of the tree has been analysed. The distribution of the soil organic carbon (SOC) into different fractions has also been determined, in order to estimate the stability of the organic matter. The results show that the SOC concentration has no dependence on the sex of the tree, but it increases with the diameter of the trunk and under the protection of the tree canopy. This study found that the organic matter of the J. thurifera forest soil has a high proportion of recalcitrant organic fraction, humin, which suggests that, given its organic matter stability, J. thurifera forest soils could be a real carbon sink. Consequently, the conservation of this type of old forest ecosystem is important for promoting carbon sequestration.

On the Early Irrigation of Gypseous Lands in Spain

AbstractGypseous lands occur mainly in arid regions of the world, where irrigation is required for profitable agriculture. The study of gypseous soils has been neglected for years in the main stream of the soil science. Agriculture and, more recently, the environmental concerns are challenging research in the countries that have extensive gypsum outcrops. Those challenges have been obvious since at least the 1960s, when economic development in some of these countries led to the construction of new irrigation schemes and associated infrastructures. This paper presents examples of documents about agriculture on gypseous soils in Spain that might be applicable to similar situations elsewhere in the world. Copyright © 2016 John Wiley &amp; Sons, Ltd.

Anthropogenic and naturally occurring radionuclide content in near surface air in Cáceres (Spain)

The anthropogenic (137Cs, 90Sr, 239+240Pu and 241Am) and naturally occurring radionuclide (40K, 234,238U, 228,230,232Th, 226Ra and 210Pb) content in near surface air present seasonal variations related to natural processes, such as soil erosion, resuspension of fine particles of soil and radon exhalation from soil (210Pb). The objective is to analyze seasonal variations of their concentrations and compare with radiological events (Fukushima fallout and wild fire) in a location without any known source of anthropogenic radionuclides. The 210Pb, 40K, and 137Cs presented annual variations, with maximum activity levels in summer. Solar radiation and rainfall were correlated with 210Pb and 40K. The 234,238U, 228,230,232Th, 226Ra, 137Cs and 90Sr presented positive correlation with monthly mean values of temperature. The ratio 90Sr/137Cs was within the range of those reported for soils in Spain. Finally, the maximal effective dose rate was estimated to be 37 and 88 μSv/y for infants and adults, respectively, well below 1 mSv/y reference level. The main contributor to effective dose was 210Pb, about 92%, followed by:210Pb ≫ 228,230,232Th > 226Ra, 234,238U > 7Be, 239+240Pu > 40K, 90Sr > 137Cs > 22Na

Exploring the potential of fungi isolated from PAH-polluted soil as a source of xenobiotics-degrading fungi.

The aim of this study was to find polycyclic aromatic hydrocarbon (PAH)-degrading fungi adapted to polluted environments for further application in bioremediation processes. In this study, a total of 23 fungal species were isolated from a historically pyrogenic PAH-polluted soil in Spain and taxonomically identified. The dominant groups in these samples were the ones associated with fungi belonging to the Ascomycota phylum and two isolates belonging to the Mucoromycotina subphylum and Basiodiomycota phylum. We tested their ability to convert the three-ring PAH anthracene in a 42-day time course and analysed their ability to secrete extracellular oxidoreductase enzymes. Among the 23 fungal species screened, 12 were able to oxidize anthracene, leading to the formation of 9,10-anthraquinone as the main metabolite, a less toxic one than the parent compound. The complete removal of anthracene was achieved by three fungal species. In the case of Scopulariopsis brevicaulis, extracellular enzyme independent degradation of the initial 100μM anthracene occurred, whilst in the case of the ligninolytic fungus Fomes (Basidiomycota), the same result was obtained with extracellular enzyme-dependent transformation. The yield of accumulated 9,10-anthraquinone was 80 and 91%, respectively, and Fomes sp. could slowly deplete it from the growth medium when offered alone. These results are indicative for the effectiveness of these fungi for pollutant removal. Graphical abstract ᅟ.

Simultaneous assessment of key properties of arid soil by combined PXRF and Vis–NIR data

SummaryArid soil is common worldwide and has unique properties that often limit agronomic productivity, specifically, salinity expressed as soluble salts and large amounts of calcium carbonate and gypsum. Currently, the most common methods for evaluating these properties in soil are laboratory‐based techniques such as titration, gasometry and electrical conductivity. In this research, we used two proximal sensors (portable X‐ray fluorescence (PXRF) and visible near‐infrared diffuse reflectance spectroscopy (Vis–NIR DRS)) to scan a diverse set (n = 116) of samples from arid soil in Spain. Then, samples were processed by standard laboratory procedures and the two datasets were compared with advanced statistical techniques. The latter included penalized spline regression (PSR), support vector regression (SVR) and random forest (RF) analysis, which were applied to Vis–NIR DRS data, PXRF data and PXRF and Vis–NIR DRS data, respectively. Independent validation (30% of the data) of the calibration equations showed that PSR + RF predicted gypsum with a ratio of performance to interquartile distance (RPIQ) of 5.90 and residual prediction deviation (RPD) of 4.60, electrical conductivity (1:5 soil : water) with RPIQ of 3.14 and RPD of 2.10, Ca content with RPIQ of 2.92 and RPD of 2.07 and calcium carbonate equivalent with RPIQ of 2.13 and RPD of 1.74. The combined PXRF and Vis–NIR DRS approach was superior to those that use data from a single proximal sensor, enabling the prediction of several properties from two simple, rapid, non‐destructive scans.

Hydrocarbon pollution from domestic oil recycling industries in peri-urban soils. Lipid molecular assemblages

The impact of continuous inputs of hydrocarbons from domestic waste oil recycling industries and further remediation practices, like inertization (liming and addition of ashes), have been studied in peri-urban soils in Spain in order to monitor the fate and spatial distribution patterns of potentially hazardous organic compounds. Physical and chemical properties of undisturbed soils or contaminated with waste-oil were determined. Lipid fractions were extracted using a dichloromethane:methanol mixture and analyzed by gas chromatography–mass spectrometry (GC/MS) in search for environmental proxies. A pollution gradient (distance to the waste oil spill) was accompanied by the following chromatographic features: (i) the increasing extent of the unresolved ‘hump’ caused by branched/cyclic alkanes with non-biogenic signature, (ii) the depletion of fatty acids and alkanol series, and (iii) the accumulation of phenols and polycyclic hydrocarbons. An increase in the C-preference index (odd-C/even-C numbered homologues) of fatty acids was also detected with an opposed trend in alkane chains. Concerning alkanes and fatty acids chain length, there was a generalized decrease whereas a progressive increase of alien long-chain (>C20) homologues was observed. Signature compounds found in waste oil (mainly squalene, steroids and waxes) were almost absent from neighbor soils, either undisturbed or inertized, suggesting the occurrence of rapid biodegradation or condensation processes in the soil matrix probably aided by the remediation practices or by abiotic humification processes.

Cretaceous-Paleogene Boundary Clays from Spainand New Zealand: Arsenic Anomalies

Abstract Remarkably high arsenic (As) contents havebeen reported in numerous Cretaceous-Paleogene boundary(KPB) clays worldwide including those from Spain (atCaravaca and Agost) and New (N.) Zealand (at WoodsideCreek). Two interpretations have been offered to explainthis anomaly. The first one suggests that this As was generatedby the combustion of fossil fuels (such as crude oil,coal or oil shales) near the Chicxulub impact site and thesecond interpretation proposes the post-impact combustionof the global biomass at the KPB. Both types of combustionwere presumably triggered by the Chicxulub impactor.This report shows that the estimated surface densitiesof As in Spain and N. Zealand strongly contradict thefossil fuel hydrocarbons/biomass hypotheses. In addition,we also show that previously reported global abundancesof As at KPB are greatly overestimated.The high abundances of iron (Fe) in the ejecta layers fromSpain and N. Zealand lead us to a working hypothesis thata major fraction of their anomalous As was adsorbed fromseawater by the Fe-oxides. These oxides were mainly derivedof Fe from the vaporized carbonaceous chondrite impactor.These were originally deposited on the local (topographicallyhigh) oxic soils in Spain and N. Zealand andthen laterally transported to the KPB sites by the impactinducedsurface waters.

Lowering iron chlorosis of olive by soil application of iron sulfate or siderite

About 70 % of the olive is grown on calcareous soils in Spain, most of which can induce iron (Fe) chlorosis. The main symptoms are interveinal yellowing of the young leaves, leaf necrosis, and reduction of leaf and shoot size, which can lead to major yield losses. Several strategies have been used to avoid Fe chlorosis such as the application of Fe chelates, but they are expensive. Here, we studied the effectiveness of synthetic siderite (FeCO3) and Fe sulfate injected in the form of suspension/solution into the soil for correcting Fe chlorosis in olives. Experiments were established in spring 2009 for four growing seasons in ‘Manzanilla,’ ‘Ocal,’ ‘Arbequina,’ and ‘Picual’ orchards. The treatments were injections of (1) a siderite suspension; (2) a Fe sulfate solution supplied with K2SO4 to make up for the K present in the siderite suspension; (3) a K2SO4 solution, named Control-K; and (4) water, named Control-0. At the start of the experiment, the suspensions or solutions were injected into the soil at 10–20 points around the tree at the depth of maximum root density. Results show that Fe chlorosis was alleviated in ‘Manzanilla’ and ‘Picual’ since leaf chlorophyll concentration (as estimated by the soil plant analysis development (SPAD) value) in the trees treated with siderite or Fe sulfate was increased by 4–7 % relative to the control trees, and leaf weight was increased by 6–9 %, but not in the ‘Arbequina’ and ‘Ocal’ trees. This finding was explained by higher available Fe in Arbequina and Ocal soils. The antichlorosis effect of iron sulfate was persistent and slightly higher than that of siderite. Both iron sulfate and siderite are not susceptible to leaching due to the low solubility of Fe oxide phases. Thus, a single application of these fertilizers constitutes a promising alternative to other Fe fertilizers, which require more than one application per year.

Draft Genome Sequence of the Moderately Halophilic Bacterium Marinobacter lipolyticus Strain SM19.

Marinobacter lipolyticus strain SM19, isolated from saline soil in Spain, is a moderately halophilic bacterium belonging to the class Gammaproteobacteria. Here, we report the draft genome sequence of this strain, which consists of a 4.0-Mb chromosome and which is able to produce the halophilic enzyme lipase LipBL.

The use of hard- and soft-modelling to predict radiostrontium solid–liquid distribution coefficients in soils

The solid–liquid distribution coefficient ( K d ) is the parameter that governs the incorporation of contaminants in soils. Its estimation allows the prediction of the fate of contaminants in the short- and long-term after a contamination event. Here, the K d of radiostrontium ( K d (Sr)), a radionuclide of significant environmental interest, was predicted by hard models, which are based on knowledge of the mechanisms governing its sorption, and by soft models based on Partial Least Squares (PLS), using a large data set with the main soil parameters. The two approaches were tested and compared for 30 soils in Spain. Correlations between the predicted and experimental values of K d (Sr) obtained using hard- and soft-modelling showed slopes close to 1 and regression coefficients higher than 0.95, which confirms that both approaches are able to obtain satisfactory estimates for K d (Sr) from soil parameters.