Different Types Of Soil Research Articles

Response of Soil Microorganisms and Phenolic to Pseudostelariae heterophylla Cultivation in Different Soil Types

Pseudostellaria heterophylla of the Caryophyllaceae family is an important medicinal herb in traditional Chinese medicine, but it encounters continuous cropping obstacle during cultivation. This study aimed to study the differences in the response of Pseudostellaria heterophylla cultivation to soil microorganisms and phenolic substances in different types of soil (Loamy soil and Clayey soil). The analysis of soil metabolites using HPLC-ESI-Q/TOF-MS and HPLC-DAD techniques revealed that the content of various phenolic components in the rhizosphere soil increased significantly after Pseudostellaria heterophylla cultivation. Pseudostellaria heterophylla cultivation in yellow soil could increase the abundance of Proteobacteria, Ascomycota, and Thermoplasmatota, while in brown soil, the abundance of Ascomycota significantly decreased. In addition, Pseudostellaria heterophylla cultivation could increase the α-diversity of bacteria and fungi in yellow soil, while reducing the α-diversity of archaea, and the impact on diversity in brown soil was relatively small. Correlation analysis showed that phenolic compounds were more likely to regulate the genera Bradyrhizobium, Calcarisporiella, Boothiomyces and Methanocella. Pseudostellaria heterophylla may regulate rhizosphere microbial diversity and community structure by secreting phenolic. However, in different types of soil environments, the response mechanism of soil microorganisms to Pseudostellaria heterophylla planting might vary. Our study provides new insights that the variability in the response of different soil types to Pseudostelariae heterophylla cultivation should be taken into account when developing strategies for reducing continuous cropping obstacles in medicinal plants.

Effect of Staggered Contour Trenches and Hillside Ditches on surface runoff and soil loss on steep slopes in shaded coffee (Coffea arabica), Costa Rica

Soil erosion is one of the main causes of soil degradation and an important environmental problem, often accelerated by human activities. Different types of soil and water conservation measures (SWCM) have been implemented in worldwide to control soil loss, such as Staggered Contour Trenches (SCT) and Hillside ditches (HD) which are recommended in topographies up to 40 % slope. This study measured the effects of STC and HD, on surface runoff, soil loss, exposed of organic matter and soil moisture content, in a shaded coffee crop with steep slopes in an Entisol soil. Nine runoff plots were installed in Llano Brenes, Costa Rica, in the upper basin of the Jesús María River in a study area with slopes between 50 and 71 ± 7.92 %. We conclude that this study could make an important contribution to research on the use of SWCM on tropical soils with slopes greater than 50 %. Due to the non-compliance of assumptions, a logarithmic transformation of the data was used, and they were evaluated using the Kruskal-Wallis one-way nonparametric test. Spearman correlation and linear regressions were used to assess the effect of the precipitation and intensity in the soil loss and runoff in each treatment. The amount of organic matter exposed by soil removal was not statistically different between HD and SCT, but both were different to the control (R2 = 0.81, P < 0.05). Spearman correlation analysis showed the rainfall depth contributed more to runoff depth (HD R = 0.62; SCT R = 0.62; Control R = 0.60; P < 0.001) and soil loss (HD R = 0.50; STC R = 0.53; Control R = 0.50; P < 0.001) than other variables. Regression analysis showed that runoff and soil loss were significant (P < 0.05) and positively correlated with rainfall depth for each treatment. In this study, HD was shown to be efficient in erosion control on steeper slopes. HD helped reduce soil loss compared to the control, by 88 % in 2018 and 83 % in 2019. HD also reduced runoff generation by 55 % in 2018 and 60 % in 2019 compared to the control. While SCT was not statistically different in the generation of surface runoff and soil loss compared to the control.

The role of zinc fertilization and its interaction with nitrogen and phosphorus starter fertilization on early maize development and grain yield

The early planting of maize in temperate growing areas leads to yield and quality benefits, although a low soil temperature can affect the early nutrient uptake and delay plant development. Not only can the nitrogen (N) and phosphorus (P) uptake be limited, but that of zinc (Zn) can also be affected. Moreover, the application of N and P at early growth stages can result in an enhancement of maize growth. Two field experiment were carried out in North Italy during the 2012–14 period to: i) evaluate the most effective Zn application strategy by comparing seed, soil and foliar applications with an untreated control; ii) investigate the role of a Zn seed treatment on the early development and yield of maize grown in three different types of soils. The effect of Zn application was compared, in both experiments, to starter NP fertilization in bands at planting, according to a full factorial design. Zn fertilization significantly enhanced the early vigor and yield of the maize, although the effects were less pronounced than those of the NP fertilizer. Among the Zn fertilization strategies, maize growth was quicker for the seed and soil applications than for the foliar application or the untreated control. The former application significantly increased the plant height at stem elongation (+32%), shortened the planting-flowering period by 1 day, and increased the grain yield by 4%. Overall, the application of NP starter fertilizer shortened the planting-flowering period by 4.5 days and increased the yield by 10%, compared to the unfertilized control. In the second experiment, higher plant vigor indices were detected in all the soils for the NP starter fertilization (+22–27%) and for the Zn seed treatment (+3–9%) than in the controls. The NP starter fertilization reduced the grain moisture at harvest by 2.3% and increased grain yield by 14%, while the Zn treatment significantly increased the kernel weight but did not affect the grain yield or the moisture content. The interaction between the NP fertilization and the Zn treatment was never significant. Thus, the positive effect of Zn on the early vigor was an additional benefit to that produced by the starter NP fertilization. The study demonstrated that a Zn application at planting, with both a seed dressing and a soil treatment, significantly enhanced the early growth of different maize hybrids, in different growing seasons and soils, although the use of a NP starter fertilization led to more consistent agronomic benefits. Furthermore, the combination of NP and Zn starter fertilization resulted in a further advantage for all the considered production situations.

AQU-FRC Net: Automated soil prediction based on faster RCNN with aquila optimization

In agriculture, selecting an “appropriate plant for an appropriate soil” is a crucial stage for all sorts of lands. There are different types of soil found in India. It is necessary to understand the features of the soil type to predict the types of crops cultivated in a particular soil. This leads to significant inconsistencies and errors in large-scale soil mapping. However, manually analyzing the soil type in the laboratory is cost-effective and time-consuming, yet it produces an inaccurate classification result. To overcome these challenges, a novel AQU-FRC Net (Aquila – Faster Regional Convolutional Neural Neural) is proposed for the automatic prediction of soil and recommending suitable crops based on a soil-crop relationship database. The soil images were pre-processed using a Scalable Range-based Adaptive Bilateral Filter (SCRAB) for eliminating the noise artifacts from the images. The pre-processed images were classified using Faster-RCNN, which utilized MobileNet as a feature extraction network. The classification results were optimized by the Aquila optimization (AQU) algorithm that normalizes the parameters of the network to achieve better results. The proposed AQU-FRC Net achieves a high accuracy of 98.16% for predicting soil. The experimental results demonstrate that the model successfully predicts the soil when compared to other meta-heuristic-based methods.

Potential biodegradable bacteria and their identification

The article describes soil bacterial isolates isolated from technogenic zones of Kyrgyzstan, possessing high oil-oxidizing and bioemulsifying activity, capable of decomposing petroleum hydrocarbons in the temperature range of 4 - 39°C at pH 4 - 9 in the presence of 18% salt. Our research has confirmed the possibility of bioremediation of the damage caused to soils as a result of chemical pollution of soils (lands) due to spillage of oil products on the territory of the oil depot in Balykchy city of Kyrgyzstan. The used bacterial consortium consisting of spore-forming bacteria of Bacillus genus: B1-025-4(2), B1-05-3(2), B1-025-5 had high oil-degrading activity both at low (4°C) and moderate (18-25°C) temperatures. In this work, special attention was paid to the molecular genetic properties of 4 bacterial strains isolated from oil-contaminated and different types of soils. The maximum biodegradability of these strains for many hydrocarbons (hexadecane, benzene, naphthalene, diesel fuel, gasoline) was also noted. Based on physiological-biochemical and molecular genetic analysis, the isolated petroleum destructor bacteria were found to belong to Bacillus pumilus (strains B1-05-3(2) and B1-025-4(2), B1-025-5) and Bacillus amyloliquefaciens (strain H-5-2). These selected strong bacterial strains are of great interest for biotechnological applications as effective microorganisms for environmental cleaning. Keywords: bacteria-destructors, effective strains, oil-contaminated soil, bioremediation, identification, molecular methods.

Солтүстік Қазақстан аймағының әртүрлі топырақ типтеріндегіазот бекітуші микроағзалардың таралуы

The use of biopreparations based on soil microorganisms to improve soil fertility, crop productivity and reduce the spread of fungal diseases of grain crops is one of the promising and environmentally friendly directions. This, in turn, requires comprehensive work on the creation, evaluation and introduction of highly effective Kazakhstani biological preparations. The article presents data on the distribution of nitrogen-fixing bacteria and actinomycetes on different types of soils in Northern Kazakhstan, identified by sowing soil suspensions by serial dilutions. More than 100 new strains of nitrogen-fixing bacteria and actinomycetes were isolated on solid selective nutrient media. In order to create a biofertiliser, the pathogenicity and growth intensity of new nitrogen-fixing bacteria and actinomycetes were studied, and their cultural and morphological characteristics were described. The 30 most active strains such as №21S, №19S, №31S, №91S, №3S, №56S, №51S, №62S, №55S, №70S, №53S, №20S, №2S, №81S, №7S, №54S, №57S, №35S, №84S, №22S, №9S, №12S, №8S, №10S, №69S, №52S, №49S, №11S, №6S, №59S, which will be used to make biologics. In the future, these strains will be studied for their growth-stimulating, fungicidal properties, etc., and will also be used in the development of microbiological technology for the production of biological preparations based on nitrogen-fixing and actinomycetes capable of increasing productivity.

Effect of supplementation of Eichhornia crassipes biomass manure on efficacy of other organic manures on the growth of Triticum aestivum

The aquatic weed E. crassipes was taken for investigation as a potential source for production of organic fertilizer. It was initially supplemented with organic manures viz. cow dung and poultry manure to study the efficacy of prepared manure. The comparative studies were performed on different types of soils. Different physicochemical and physical parameters of plant growth were determined. Results with saline soil showed an interesting effect on growth of wheat plants. The results were highly promising and proved to show better effects on the growth of wheat plants. The addition of E.crassipes organic manure increases the organic content of red soil to the extent of 20.7%, black soil to the extent of 20.5% and saline soil to the extent of 15.5%. The aquatic weed water hyacinth may be a low cost alternative source of organic fertilizer in plenty full supply. The possible ways of combating its proliferation and the various methods of eradicating this weed not proved much. Then its utilization may become an eary way of its management. The results also signify the use of E. crassipes as the organic manure. The study of water hyacinth as biofertilizer revealed that the incorporation of water hyacinth into soil crops system increased the performance of the wheat plant. Since water hyacinth is locally available, plentiful and cost free, its effective use as organic soil amendment would be an interesting method for soil restoration. Its use for manure preparation will help get rid of this notorious weed which causes aquatic environmental pollution problems.

Modeling sorption of environmental organic chemicals from water to soils

Reliable estimation of chemical sorption from water to solid phases is an essential prerequisite for reasonable assessments of chemical hazards and risks. However, current fate and exposure models mostly rely on algorithms that lack the capability to quantify chemical sorption resulting from interactions with multiple soil constituents, including amorphous organic matter, carbonaceous organic matter, and mineral matter. Here, we introduce a novel, generic approach that explicitly combines the gravimetric composition of various solid constituents and poly-parameter linear free energy relationships to calculate the solid-water sorption coefficient (Kd) for non-ionizable or predominantly neutral organic chemicals with diverse properties in a neutral environment. Our approach demonstrates an overall statistical uncertainty of approximately 0.9 log units associated with predictions for different types of soil. By applying this approach to estimate the sorption of 70 diverse chemicals from water to two types of soils, we uncover that different chemicals predominantly exhibit sorption onto different soil constituents. Moreover, we provide mechanistic insights into the limitation of relying solely on organic carbon normalized sorption coefficient (KOC) in chemical hazard assessment, as the measured KOC can vary significantly across different soil types, and therefore, a universal cut-off threshold may not be appropriate. This research highlights the importance of considering chemical properties and multiple solid constituents in sorption modeling and offers a valuable theoretical approach for improved chemical hazard and exposure assessments.

Comparative Study of the Diesel Fuel Contamination Effects of Different Types of Soils on the Growth and Germination of Four Plant Species

Comparative Study of the Diesel Fuel Contamination Effects of Different Types of Soils on the Growth and Germination of Four Plant Species

EFFET DE LORPAILLAGE SUR LABONDANCE ET LA DIVERSITE DES ESPECES DE CHAMPIGNONS MYCORHIZIENS ARBUSCULAIRES DANS LA REGION CENTRALE DU TOGO

Gold mining has a negative impact on the soil include microorganisms such as Arbuscular Mycorrhizal Fungi (AMF). The AMF form associations with plants by improving their development However, the effect of gold mining on Arbuscular Mycorrhizal Fungi (AMF) living in its soils is poorly understood.The objective of this study was to characterize the effect of gold mining on the abundance and diversity of AMF species in the Central region of Togo. The AMF were extracted by wet sieving from 200g of soil samples taken directly from four types of soil, Gold Soil (SA), Washed Gold Soil (SAL), Soil Under Corn Cultivation (SSCM) and the Soil Under Natural Vegetation (SSVN). The diversity of AMF was determined by diversity indices. The results showed that SA, SSCM and SSVN had significantly higher AMF fungal spores densities (p &lt; 0.05) than SAL. AMF species richness was generally lower in SAL (12 species out of a total of 30 species identified). A total of 30 AMF species classified into 16 genera, in 9 families (AcaulosporaceaeAmbisporaceae, Archaeosporaceae, Gigasporaceae, Claroideoglomeraceae, Dentiscutataceae, Diversisporaceae, Glomeraceae, Paraglomeraceae) were identified. The most frequent species were Acaulosporascorbiculata, Acaulospora sp., Entrophosporainfrequens, Gigaspora gigantea, Claroideoglomusetunicatum. The most abundant species were Acaulosporascorbiculata, Acaulosporasp., Entrophosporainfrequens, ClaroideoglomusEtunicatum, Glomus clavisporum, and Rhizophagusintraradices. The biological diversity indices (Shannon and Pielou equitability) revealed a significant difference (P &lt; 0.05) between the different types of soils studied. The density of the spores as well as their diversityvary as follows: SAL&lt;SA&lt; SSVN&lt; SSCM. The soils of the study area contain a great natural wealth of AMF species, but this natural wealth is significantly affected by gold panning. The native AMF found in these areas could be used for the ecological restoration of degraded gold panning areas.

РІЗНИЦЯ В РОБОТІ БУРОВИХ І ЗАБИВНИХ ПАЛЬ У СКЛАДІ СТРІЧКОВОГО ПАЛЬОВОГО ФУНДАМЕНТУ

A comparative analysis of the results of the mathematical modeling of the strip pile foundation from driven and bored piles with one-row and two-row arrangement of piles with different longitudinal steps and different lengths in different types of soil was performed.&#x0D; It was established that the degree of implementation of the load-bearing capacity of piles and grids as part of a strip pile foundation depends not only on the relative length and pitch of the piles, but also on the method of their arrangement. Taking into account the actual operation of piles and grids as part of the pile foundation allows to increase the load-bearing capacity of the pile foundation as a whole and, accordingly, to save material and labor resources during construction work.&#x0D; Based on the results of the study, the difference in the operation of drilled and driven piles in the strip pile foundation was established. The load-bearing capacity of a low grid as part of a strip pile foundation on bored piles is 1.5-2 times greater than in pile foundations made of driven piles. The degree of implementation of the load-bearing capacity of the pile as part of the pile foundation is significantly greater for foundations made of drilled piles compared to foundations made of driven piles. For foundations made of driven piles, at step 3d - 6d, the piles in the strip do not fully realize their load-bearing capacity. Drill pile groups increase their load-bearing capacity by working in a group, even with a minimum pitch.&#x0D; Since pile foundations from drilled piles significantly increase their bearing capacity due to the joint work of their elements under load in comparison with pile foundations from driven piles, taking into account this joint work, pile foundations from drilled piles become competitive with similar foundations from driven piles.

Pounding induced overturning resistance of FPB-isolated structures considering soil-structure-interactions

This study explores the overturning resistance performance of friction pendulum bearing (FPB) isolated structure when pounding occurs during earthquake actions, and considers the soil-structure-interaction (SSI) effect. The dynamic responses and overturning resistance performance of structures under a series of seismic records were comprehensively analyzed for three different types of soils and fixed-base structure. The effects of displacement ratio, equivalent radius ratio and friction coefficient ratio on the overturning resistance performance of the isolated structures were evaluated through parametric study. It is demonstrated that the system exhibit superior overturning resistance performance in soft soil foundation case, surpassing the performance when SSI is ignored. However, the overturning resistance performance of structure with a dense soil foundation is similar to the fixed-base structures. Moreover, the results reveal that the overturning resistance coefficient initially increases and then decreases with an increase in the equivalent radius ratio and friction coefficient ratio subjected to pulse-type seismic record, but it increases with an increase in the pounding displacement ratio. The overturning resistance performance increases with an increase in the equivalent radius ratio, friction coefficient ratio, and displacement ratio when the structures are subjected to non-pulse-type seismic records.

A Modified Method for the Fredlund and Xing (FX) Model of Soil-Water Retention Curves

The soil-water retention curve (SWRC) is fundamental in presenting the hydromechanical characteristics of soils, which are closely connected with soil deformation, permeability, and shear strength. The Fredlund and Xing (FX) model accurately fits the SWRCs of different types of soils over a wide suction range. However, experimental comparisons of the fitting showed that the obtained parameters differ from the physical meanings assigned by Fredlund and Xing. To address this issue, the traditional FX model has been improved, resulting in the proposal of a two-step FX model. Firstly, the FX model is applied without taking the correction coefficient c(ψ) into account to fit the measured SWRC. The values for α, n, and m are then determined and substituted into the FX model to refit the experimental data. Finally, the last parameter Cr can be obtained. The curves resulting from these two steps have a good agreement with the experimental results, and the obtained parameters align better with their physical meanings.

Primjena biopreparata kao alternativa kemijskim fungicidima u zaštiti pšenice

Two-year experiments were conducted on two different types of soil during 2021 and 2022, respectively. The influence of microbiological preparations Mycor-FAZOS, Vitality-FAZOS, and Super Green-FAZOS on the yield and quality parameters of wheat the Mura variety (Agrigenetics) was investigated. The experiment was set up according to the split-block scheme in four repetitions on two types of soil, in 12 different variants on each of them. The area of the basic plot amounted 40 m2, while the calculated plot amounted to 24 m2. The elements of the research were as follows: A (soil type) – A1 – humogly, A2 – eutric brown soil; B (seed treatment) – B1 – control, B2 – seed treated with biopreparation; C (protection against diseases) – C1 – control, C2 – treatment with chemical fungicides, C3 – treatment with biopreparations. The research parameters were grain yield (t/ ha), protein content in grain (%), mass of 1,000 grains (g), hectoliter mass (kg), and plant height (cm). The highest average grain yield was obtained by the B2C3 variant, where the yield was 17.42% higher than the yield obtained by the B1C2 variant. In terms of protein content, the difference between the mentioned varieties was 4.24%, in the weight of 1,000 grains 6.36%, in hectoliter weight 6,35%, and 6,87% in plant height. We can conclude that a seed treatment with the Mycor-FAZOS biopreparation has improved root development, so the plants were healthier, taller, and more robust, but it has improved a uniform growth too, so the plants were darker than the untreated seed variants (scoring an increased photosynthesis index). The protection performed with the Vitality-FAZOS and Super Green-FAZOS biopreparations (i.e., the microorganisms that have an extremely fungicidal effect but also synthesize growth hormones) ensured that the wheat remained healthy while achieving a higher seed yield and obtaining a better quality of research parameters.

Прогнозирование переизлученного шума и вибрации, создаваемых вблизи железнодорожных линий

Purpose: To analyze a ScopeRail model capable of predicting re-radiated noise and vibration in structures located in close proximity to rail lines. To compare the obtained results with an alternative, widely used model for accuracy assessment and the potential cost reduction of assessing the impact of vibrations on residential areas for new railway lines. Methods: To perform statistical analysis of the obtained data for modeling vibration of different types of ground. To calculate simulation results in order to create a database of vibration characteristics for different ground conditions, train speeds and distances from the track. Results: The results obtained have been analyzed and compared with an alternative, widely used model for determining accuracy. It is found that the ScopeRail model yields higher prediction accuracy, which can potentially reduce the cost of assessing the impact of vibrations on residential areas for new rail lines. A model is obtained which can instantly predict the vibration and re-radiated noise levels for different types of soil at different speeds of passing trains. Practical significance: Re-radiated vibration and noise model for the spaces in buildings immediately adjacent to the railroad track has been developed using a set of empirically obtained factors. Vibration and noise impacts have also been modeled using additional vibroacoustic mitigation measures (slabs and ballast mats) as well as vibration excitation parameters (switches, crossings and wheel stoppers).

The factors of the low iodine concentration in soil cover and drinking waters of the second ridge of the Mountain Crimea

Low iodine content in the environment can be one of the main factors of iodine deficiency diseases in humans and farm animals, including hypothyroidism, nodular thyroid tumors, irreversible brain damage in the fetus and newborn. Endemic goiter, caused primarily by iodine deficiency, is an urgent problem for most regions of modern Russia, including the Republic of Crimea. For the Republic of Crimea, along with other regions of the Crimean-Caucasian mountain zone, there is a deficiency of iodine in the lower links of the trophic chain, which provokes iodine deficiency diseases. The aim of the work was to reveal the contrast of iodine distribution in the lower links of the trophic chain: different types of soils for agricultural use and natural waters for drinking purposes from various sources in the Crimean Mountains. The article presents data of the iodine content in the soil cover and drinking water in the Crimean Mountains, on the example of the Bakhchisarai area (in Bodrak river valley). The dependence of the iodine content in the upper horizons of different types of soils, on the content of humus, pH-water soils and cation exchange has been established. It has been confirmed that the content of iodine in natural waters (springs, rivers, lakes) is determined primarily by the composition of water-bearing rocks.

Soil Chemical Properties, Distribution of Zinc Fractions and Zn Uptake by Rice as Influenced by Long Term Application of Inorganic Fertilizers and Organic Manures: A Review

Zinc (Zn) deficiency is one of the important abiotic factors limiting rice productivity worldwide and is also a widespread nutritional disorder affecting human health. Zinc deficiency greatly influences and changes the soil physico-chemical properties over long application of inorganic fertilizers and organic manures on different type of agricultural soils. Given that rice is a staple for populations in many countries, studies of Zn dynamics and management in rice are of great importance in different agroclimatic regions of agricultural soils. In this context, the continuous application of chemical fertilizers and organics has widely affected the zinc dynamics, nutrient content and their uptake by rice crop.

The running gear construction impact on overcoming obstacles by light high-mobility tracked UGV

Rubber tracked running gears are widely used in high-mobility Unmanned Ground Vehicles (UGV) to increase obstacle negotiation possibility in urban and rural terrain. The paper proposes a method of assessing the mobility level of the light UGV‘s tracked running gears in terms of their ability to overcome terrain obstacles. A model of rubber track system was created in the MSC ADAMS environment. A track-ground contact was also modeled, defining the traction force based on the Wong equations. For four different chassis models (rigid construction, bogies solution – rigid and elastically mounted to the frame and rocker-bogie construction), with two track tension variants, the ability to overcome five terrain obstacles was checked, taking into account three different types of soil. The solutions were accessed on the basis of parameters of general efficiency of overcoming obstacles, driving force and slip values, as well as the distribution of track pressures on the ground. The best solutions for each criterion were indicated. The simulation results showed an improvement in the driving properties with the use of elastically suspended elements. The results also emphasized the negative impact of increased track tension on overcoming obstacles and the impact of ground characteristics on the slip values of the running gear.

Profile distribution of polycyclic aromatic hydrocarbons in coastal soils of the Lower Don and Taganrog Bay, Russia

The main regularities of pollutant distribution through the soil profile were established based on the analysis of the content of 15 priority PAHs in 29 soil sections of different soil types located in the coastal zone of the Lower Don and Taganrog Bay with different anthropogenic loads. It was shown that the total content of PAHs in the 0-20 cm layer of soils of coastal territories varies from 172 µg kg-1 to 16006 µg kg-1. In addition, according to the total pollution indicator, (Zc) determines the level of soil pollution, which varies from "not polluted" to "extremely polluted". The influence of pollution sources falls on the 0-20 cm layer of soils of different types and is especially pronounced for subordinate landscapes. With increasing sampling depth, the total PAH content decreases with the redistribution of individual compounds of the PAH group towards the dominance of low molecular weight and 4-ring compounds in the composition of the sum of 15 PAHs and depends largely on the content of organic matter and soil pH. Based on the cluster analysis results, the main factor determining the profile distribution of PAHs is the type of pollutant origin source and its intensity.

Use of pollen assemblages as forensic evidence in non-seasonal high-altitude soils

Forensic palynology is a tool in criminalistics that uses spores and pollen grains to link a certain geographical location with a crime scene. The comparison of the pollen assemblage of a crime-scene soil and that of footwear of suspects and victims proved to be very useful as judicial evidence in multiple environments with marked seasonality. However, its usefulness in non-seasonal high-altitude soils has not been experimentally evaluated to the same extent. For this reason, the present study addressed this information gap by undertaking a palynological study in areas with high crime rates in the city of La Paz, Bolivia. To do this, we carried out multiple experimental samplings in three locations with different types of soil and different degrees of urbanization. Specifically, we compared whether the vegetation present at the time of taking the reference samples, was reflected in the pollen rain. Results showed that the vast majority of the species present in the vegetation were found in the pollen rain, with the exception of some plant species with entomophilous pollination syndrome. We also show that the transfer between assemblages from pollen rain to footwear happened effectively, which helped identify their geographical origin, and unveiled a great number of useful indicator species.