Agricultural Sites Research Articles

Human health risks in Ferozepur District, Punjab, India due to potentially toxic elements in agricultural soils

In the present study, soil contamination by arsenic, cadmium, chromium, cobalt, copper, iron, lead, manganese, nickel, uranium and zinc; and associated human health risks were assessed at 30 agricultural sites in Ferozepur District, Punjab. Above 90% soil samples had high content of chloride, sodium and potassium. Cadmium, arsenic, zinc and lead in 100%, 76.67%, 76.67% and 66.67% samples exceeded their safe limits (mg/kg; 0.06, 20, 50 and 10, respectively). Individual/multi-elemental indices indicated high PTEs contamination in soils posing low to considerable ecological risk. Principal components PCI and PCII contributed 44.748% and 30.476% variance in data, respectively. PTEs in soils were classified in two categories using cluster analysis (I: Cd, U, Co, Pb, Ni, Cr, As, Cu, Zn and Mn; II: Fe), indicating both geogenic and anthropogenic origins. Health risks due to PTE exposure via dermal contact, inhalation and ingestion were also assessed. Children were found to be highly prone to non-cancer health risk (mean hazard index = 1.30) by As exposure, mainly via ingestion pathway. High total cancer risk was posed to residents via As (7.52E-05) and Cr (9.17E-06) exposure, primarily through ingestion. Bioremediation and efficient disposal of solid and liquid wastes may reduce soil contamination in the study area.

Passive monitoring of avian habitat on working lands.

Intensive agricultural landscapes are a challenge for wildlife managers, policy makers, and landowners hoping to increase the diversity of desired wildlife species, such as grassland birds, which require urgent conservation action. In intensive agricultural landscapes, like those of the midwestern USA, most land area is privately owned and operated and managed primarily for production. Conducting ecological research in intensive agricultural landscapes thus requires collaborative approaches aimed at farm owners and operators. Recent advances in acoustic data collection and high-resolution habitat mapping, including low-cost acoustic recorders and satellite remote sensing, may be well positioned to address this challenge by enabling expanded assessments and monitoring of wildlife populations and habitats across regions. This study examined fine grain habitat characteristics and their relationship with avian biodiversity in intensive agricultural landscapes at 44 agricultural sites across Iowa, USA. Passive acoustic monitoring and manual identification of bird species allowed for measurement of vocalizing bird richness. High resolution mapping of noncrop vegetation provided detailed information on small noncrop vegetation habitat complexes within row-crop agriculture. Measures of image texture provided characterizations of compositional heterogeneity within noncrop vegetation. General linear Poisson modeling demonstrated robust associations between noncrop vegetation and vocalizing bird richness, yet variation in grassland bird richness was not well predicted by noncrop vegetation. Noncrop vegetation texture demonstrated potential as a predictor of vocalizing bird richness, though not better than or when combined with noncrop vegetated area, indicating it may not be an independent measure of habitat quality. Passive acoustic monitoring resulted in useful data at 44 out of 60 originally selected sites, with some lost to failed recorders and/or collaboration issues. Challenges remain in detecting habitat characteristics that promote grassland birds in row crop landscapes. Working toward probabilistic research design across privately owned working landscapes and incorporating more detailed management practice information would improve the transferability of this approach to farmland management and policy.

Combining taxonomic and functional approaches to assess land‐use impacts on macroinvertebrate assemblages and improve bioindication

AbstractMost studies exploring land use impacts have focused on taxonomic metrics, but interest in the functional approach has increased because it helps to understand the relationships between community structure and functioning of aquatic ecosystems. We evaluated how functional and taxonomic approaches, and the association between them, contribute to assessing the effects of land use on macroinvertebrate assemblages of lowland streams. We sampled benthic macroinvertebrates in 17 sites with different land uses (agricultural, peri‐urban, and extensive livestock) in Buenos Aires, Argentina. We computed the taxonomic metrics and biotic indexes as well as functional richness (FRic), divergence (FDiv), dispersion (FDis), and Rao diversity indexes for each site. We performed general linear mixed models to compare land‐uses, a redundancy analysis, and also performed correlation analysis between taxonomic and functional indexes. Taxonomic richness was significantly higher in extensive livestock than in the other two land uses, while Shannon diversity was significantly different between land uses (extensive livestock > peri‐urban > agriculture). FRic and FDiv were significantly lower in peri‐urban land use than in agricultural and extensive livestock sites. Only taxonomic richness showed a significant and positive relationship with FRic, FDis, and Rao, but they fit better to a logarithmic function. Therefore, an increase in taxonomic richness and Shannon diversity did not necessarily imply an increase in the functional aspects of the macroinvertebrate assemblage. Using only one of these approaches could lead to partial evaluations and loss of information. Combining them could improve bioindication and predictive potential and help assess the effects of multiple stressors on freshwater ecosystems to improve biomonitoring.

A new sample preparation approach for the analysis of 98 current-use pesticides in soil and herbaceous vegetation using HPLC-MS/MS in combination with an acetonitrile-based extraction

A simple acetonitrile-based extraction method for the determination of 98 current-use pesticides (CUPs) in soil and herbaceous vegetation using HPLC-ESI-MS/MS is reported. The method was optimized in terms of extraction time, buffer (ammonium formate) ratio, and graphitized carbon black (GCB) ratio for the clean-up of vegetation. The validated method yielded accuracy in terms of percentage recovery of 71–125% (soil) and 70–117% (vegetation) for the majority of 98 CUPs. The precision in terms of relative standard deviation was at 1–14% (soil), and 1–13% (vegetation). Matrix-matched calibration curves exhibited good linearities (R2 > 0.99). The limits of quantitation ranged between 0.008 and 21.5 μg kg−1 in soil and vegetation. The reported method was applied to soils and vegetation from 13 agricultural sites across Germany. Overall, 44 of the 98 common CUPs were detected in our samples and the qualitative load is well above the average for arable soils in the EU.

Status of potentially toxic metal pollution in the agricultural soils near to India’s largest chromite mine

This study highlights the contamination of potentially toxic elements (PTEs-- Cd, Cr, Fe, Ni, Pb, Mn, and Zn) in five agricultural sites near to the Sukinda chromite mine, at Odisha, in India. The results indicated that Fe and Cr had very high concentration 5758–12687 mg kg−1 and 2144–5588 mg kg−1 respectively, followed by the concentrations of Ni, Mn, Zn, and Cd. The geoaccumulation study indicated ‘moderately to heavily contaminated’ with Cr in all the studied sites while ‘high to extremely high’ Cd concentration in the sites S1, S3, and S5. The ecological Risk Index also indicated few study sites have‘ considerable to very high potential risk’ due to PTEs concentration, which is concerning for agriculture, food security, and human health for the sustainable future. This pilot scale study proposes policy-level interventions to address the PTEs pollution in this region.

Influence of land use changes on groundwater quality – Bafoussam, West Cameroon

Abstract The purpose of this work was to show that the change in land use impacts the quality of free groundwater and therefore the health of the population in the city of Bafoussam. Land use was dominated by housing (about 42%) followed by agricultural areas (33%) and green space. The socio-economic diagnosis by the guided survey showed that 62.5% of the population consumes CAMWATER water with malaria as the dominant water-related disease. The collection of water samples analysed by the colorimetric and photometric assay has allowed us to obtain a dominant water facies of the chloride and sulphate–calcium–magnesium type. The mapping of areas potentially vulnerable to pollution by ArcGIS 10.8 software presents the low-lying areas, downstream of agricultural sites, close to industries and neighbourhoods with strong urban disorder as the most vulnerable to pollution and therefore retained as actors of diffuse groundwater pollution in the city of Bafoussam. Thus, the change in land use and the increase in agglomeration degrade the quality of groundwater in this city.

Effect of tillage systems combined with plastic film mulches and fertilizers on soil physical properties in a wheat-agricultural site in southern Iraq

This study researches the influence of the three tillage systems (conventional, economical and mulch tillage) when combined with different soil plastic mulching and fertilizer applications on key selected soil physical properties (SPP) at 0-20 cm soil depth in a wheat agricultural site, during summer (from 1st June to 31st July 2015). SPP include soil porosity (Φ), volumetric soil water content 60 days after irrigation to field capacity (q60), and mean weight diameter of aggregates (MWD). The term mulch tillage refers here to a soil conservation practice where the soil surface is disturbed by tillage whereby crop residues are mixed with the soil and a certain amount of residues remain on the soil surface, while mulching refers to the placement of inorganic material over the top of a soil surface to protect it. Soil treatments included tillage system: conventional tillage using a combination of a mouldboard plough and a disc harrow (MP+DH), economical tillage using a rotary cultivator (RC), and mulch tillage using a chisel plough (MT+CP); soil plastic mulching: transparent mulching (TM), black mulching (BM) of 200 cm wide with 0.05 cm thick, and without mulching (WM); and fertilisers: composed organic fertiliser (CoF), no-composed organic fertiliser (NoF), and chemical fertiliser (ChF). The split–split-plot design under the randomized complete block design (RCBD) was established in 27 treatments with 3 replicated, to map Φ, q60, and MWD based on 81 soil samples from all treatments. Results showed that the different soil treatments have diverse impacts on SPP. MP+DH resulted in the higher q60 (0.22 cm3 cm-3), MWD (0.85 mm), and Φ (56.87%). Our findings showed that MT+CP obtained a higher MWD of 0.98 mm and lower Φ of 49% compared to other tillage systems. Soil mulching had significantly modified SPP, with BM resulting in the highest Φ (55.65%), q60 (0.35 cm3 cm-3), and MWD (1.06 mm). Results indicated no significant differences between fertiliser types on SPP. The CoF had a significant effect on MWD and related soil characteristics studied. These findings can help us to understand the individual and combined effects of the tillage system, mulching, and fertilization application on some soil characteristics in wheat agriculture. A further study with more focus on the influence of tillage depths and mulching types (plastic vs organic mulch for different crops) under a variety of soils and climatic conditions, as well as on soil thermal properties needs further investigation.

Characterization of potential Spanish territories for creating a national network associated with the Globally Important Agricultural Heritage Systems

The interest in conserving the world's agricultural heritage involves recognizing and protecting traditional farming systems as a source of learning that could help face the challenge of climate change. For this reason, since 2022, the Food and Agriculture Organization of the United Nations (FAO), through the Globally Important Agricultural Heritage Systems (GIAHS) program, promotes the initiative to identify and safeguard potential sites with agricultural systems, associated with their landscapes, biodiversity, traditional knowledge, and culture. In that context, this study aims to identify and quantify the traditional agricultural systems in the Spanish territory, under the GIAHS criteria. It offers an initial approach to potential sites for setting up a national network and for increasing proposals for designating GIAHS sites. The methodology consisted of four stages: the first was a literature review and identification of agroecosystems sites, the second was a characterization based on GIAHS criteria, the third was a spatial distribution analysis, and the fourth was a relevance classification and recognition of potential sites. The results showed that from a list of 173 Spanish sites, 50 potential agroecosystems were identified. 15 of them were classified with very high potential, confirming the potential for the creation of a national network of agricultural sites.

Urban land uses shape soil microbial abundance and diversity

Soil microbial biodiversity provides many useful services in cities. However, the ecology of microbial communities in urban soils remains poorly documented, and studies are required to better predict the impact of urban land use. We characterized microbial communities (archea/bacteria and fungi) in urban soils in Dijon (Burgundy, France). Three main land uses were considered – public leisure, traffic, and urban agriculture – sub-categorized in sub-land uses according to urban indexes and management practices. Microbial biomass and diversity were determined by quantifying and high-throughput sequencing of soil DNA. Variation partitioning analysis was used to rank soil physicochemical characteristics and land uses according to their relative contribution to the variation of soil microbial communities. Urban soils in Dijon harbored high levels of microbial biomass and diversity that varied according to land uses. Microbial biomass was 1.8 times higher in public leisure and traffic sites than in urban agriculture sites. Fungal richness increased by 25 % in urban agriculture soils, and bacterial richness was lower (by 20 %) in public leisure soils. Partitioning models explained 25.7 %, 46.2 % and 75.6 % of the variance of fungal richness, bacterial richness and microbial biomass, respectively. The organic carbon content and the C/N ratio were the best predictors of microbial biomass, whereas soil bacterial diversity was mainly explained by soil texture and land use. Neither metal trace elements nor polycyclic aromatic hydrocarbons contents explained variations of microbial communities, probably due to their very low concentration in the soils. The microbial composition results highlighted that leisure sites represented a stabilized habitat favoring specialized microbial groups and microbial plant symbionts, as opposed to urban agriculture sites that stimulated opportunistic populations able to face the impact of agricultural practices. Altogether, our results provide evidence that there is scope for urban planners to drive soil microbial diversity through sustainable urban land use and associated management practices.

Composition and Nutrition of Wild Bees in Solanum melongena L. Agroecosystems in Pune, Maharashtra, India

Eggplant, (Solanum melongena L.), also called aubergine or Guinea squash, in the nightshade family (Solanaceae) is an economically important crop in India. We investigated the significance of Solanum melongena pollen in the diet of wild bees found in agroecosystems by examining pollen on the bees using a pollen load analysis and a nutritive analysis. We selected five agricultural sites that cultivate S. melongena near Pune, Maharashtra, India. At each site, over a two-year period, we sampled the wild bees that visited mature flowers. We sampled pollen from mature flowers and also from the bodies of the bee specimens. The pollen grains from the bees were observed under a light microscope and a scanning electron microscope. They were counted using a Neubauer chamber and the pollen probability index for each bee species was calculated. The nutritive value of S. melongena pollen was estimated by extracting and characterising their proteins using liquid chromatography mass-spectrometry. Protein peptides sequences were extracted from the NCBI protein database to examine their essential amino acids. We collected 324 bees representing 11 species in three families involved in S. melongena pollination. Apis florea and A. cerana were the most abundant bees that visited S. melongena flowers. Pollen load size is highly variable ranging between few thousand to 134146 pollen grains per bee. However, the pollen probability index indicated a high degree of specificity to S. melongena pollen. S. melongena has high pollen protein content and a total of 10 different proteins were identified that are important for plant cell activities as well as the nourishment of pollinators. Further proteomic characterization of the indicated that nearly half the essential amino acids played and nutrient role in the bees. This study highlights that nutrititive composition of S. melongena pollen and highlights its potential to play a significant role in wild bee diets.

Reconnaissance of Oxygenic Denitrifiers in Agriculturally Impacted Soils.

Row crop production in the agricultural Midwest pollutes waterways with nitrate, and exacerbates climate change through increased emissions of nitrous oxide and methane. Oxygenic denitrification processes in agricultural soils mitigate nitrate and nitrous oxide pollution by short-circuiting the canonical pathway to avoid nitrous oxide formation. Furthermore, many oxygenic denitrifiers employ a nitric oxide dismutase (nod) to create molecular oxygen that is used by methane monooxygenase to oxidize methane in otherwise anoxic soils. The direct investigation of nod genes that could facilitate oxygenic denitrification processes in agricultural sites is limited, with no prior studies investigating nod genes at tile drainage sites. Thus, we performed a reconnaissance of nod genes at variably saturated surface sites, and within a variably to fully saturated soil core in Iowa to expand the known distribution of oxygenic denitrifiers. We identified new nod gene sequences from agricultural soil and freshwater sediments in addition to identifying nitric oxide reductase (qNor) related sequences. Surface and variably saturated core samples displayed a nod to 16S rRNA gene relative abundance of 0.004% to 0.1% and fully saturated core samples had relative nod gene abundance of 1.2%. The relative abundance of the phylum Methylomirabilota increased from 0.6% and 1% in the variably saturated core samples to 3.8% and 5.3% in the fully saturated core samples. The more than 10-fold increase in relative nod abundance and almost 9-fold increase in relative Methylomirabilota abundance in fully saturated soils suggests that potential oxygenic denitrifiers play a greater nitrogen cycling role under these conditions. IMPORTANCE The direct investigation of nod genes in agricultural sites is limited, with no prior studies investigating nod genes at tile drains. An improved understanding of nod gene diversity and distribution is significant to the field of bioremediation and ecosystem services. The expansion of the nod gene database will advance oxygenic denitrification as a potential strategy for sustainable nitrate and nitrous oxide mitigation, specifically for agricultural sites.

짐 운반능력을 향상시키기 위한 수동 상지 외골격장치(H-Frame) 개발

Carrying heavy objects in agricultural and industrial sites is the most basic labor, which requires a lot of energy. Many equipment such as crane, chain block, elevator, and forklift truck has been developed to reduce human power. Nevertheless, many tasks require human labor. In addition, rapid aging is increasing musculoskeletal diseases in industrial workers. Consequently, various muscle auxiliary wear robots and devices are being developed. In this study; a passive upper limbs exoskeleton (H-Frame) was developed to help carry over 20 kg of weight in industrial and agricultural sites. For the functional test of the developed H-Frame, tests were carried out for 20, 30, and 40 kg of each box. To measure the objective and numerical data of the H-Frame, various sensor values such as EMG (Electromyography), harness compression force sensor, and load cell value of side support and rope were measured. EMG and metabolic experiments were also performed on 8 subjects before and after wearing the device. The average value of the upper extremity muscle showed a 44% reduction effect after wearing. The device helped the wearer when carrying heavy objects. It could help prevent musculoskeletal diseases in industrial and agricultural fields.

Fauna-microbe diversity coupling lost in agricultural soils: Implications from the bacteria hidden in earthworm gut

Earthworms are critical for supporting soil health and microbial diversity and simultaneously maintaining a highly diverse gut microbiome. The earthworm is predominantly vulnerable to physical disturbance, yet how changes in earthworm diversity influence the richness and ecological network of soil-gut microbiomes in response to anthropogenic disturbance is virtually unknown. Here, we investigated the richness of earthworms, and their connection with the diversity of the soil-gut microbiome using a large-scale survey covering paired agricultural and natural sites. Our results showed that earthworm diversity was positively correlated with soil and gut bacterial diversity across sites. However, the connection between soil bacterial and earthworm diversity is lost in agricultural ecosystems. We further show that earthworm richness supported greater modularity in microbial networks, being both positively correlated with the richness of earthworm gut bacteria in both land-use types. Together, we provided the first empirical evidence that agricultural practices can break the fundamental links between soil bacterial and earthworm diversity, and further identify an unreported consistent connection between the diversity of earthworms and the modularity of microbial networks in natural and managed ecosystems. These findings emphasize the primary roles of earthworms in supporting soil biodiversity and point to the wider contributions of the soil animal-microbe interactions in preserving the whole soil biodiversity in anthropogenically disturbed ecosystems.

PH drives the spatial variation of antibiotic resistance gene profiles in riparian soils at a watershed scale

Owing to convenient water access, riparian areas are often sites for intensive livestock breeding industries and agriculture, which can increase the spread of antibiotic resistance genes (ARGs). However, studies on ARG profiles in riparian soils are limited and there is little information regarding the factors influencing ARGs at a watershed scale. Here, we analyzed ARG profiles, bacterial communities, and soil properties in riparian soils under different land-use types. A total of 124 ARGs and 25 mobile genetic elements (MGEs) were detected in the riparian soils, which covered almost all major classes of antibiotics. Non-metric multidimensional scaling analysis showed that both the distance to the water reservoir and land-use types played important roles in shaping ARG profiles in riparian soils at a watershed scale. Downstream soils harbored three times the abundance of ARGs compared with upstream and midstream soils. Distance-decay analysis indicated that the similarity of ARG profiles and bacterial community composition decreased significantly with the increase of geographical distance (p < 0.001). When taking the land-use type into consideration, the relative abundance and diversity of ARGs and MGEs in orchard and farmland soils were significantly higher than those in wasteland soils. This indicated that anthropogenic activities can also affect ARG patterns in riparian soils. MGE abundance was identified as major driving factors of ARG profiles. In addition, among all the examined soil properties, soil pH was found to be more important than nutrients and organic carbon in shaping ARG profiles. Our findings provide valuable data on ARG distribution in riparian soils in a reservoir catchment and highlight downstream soils is crucial for ensuring water source security.

E-Commerce in German Agriculture: A Case Study Investigating Farmer Satisfaction Applying the Thinking Aloud Method

E-commerce in agriculture is gaining increasing attention, but market penetration is currently low, and companies are barely exploiting its full potential. Identifying and satisfying farmers’ expectations of e-commerce websites for farm inputs is crucial to reduce this opportunity loss. This paper presents a qualitative case study using the “thinking aloud” method, investigating the factors of an agricultural e-commerce site that need to be improved to increase customer satisfaction. The results reveal that farmers’ dissatisfaction with and reluctance to engage in agricultural e-commerce are linked to deficiencies in the store design. These deficiencies are especially apparent in the incongruent design of off- and online stores. Congruity is needed not only in terms of price but, more importantly, in terms of design (e.g., navigation, product order) and services. However, this is often lacking. High channel congruence improves trust in the online provider and keeps perceived transaction costs low. The study emphasizes the importance of customer centricity and a channel integration strategy in agricultural trade and provides indications of which elements lead to higher customer satisfaction.

Diverting residual biomass to energy use: Quantifying the global warming potential of biogenic CO2 (GWPbCO2)

AbstractTo calculate the global warming potential of biogenic carbon dioxide emissions (GWPbCO2) associated with diverting residual biomass to bioenergy use, the decay of annual biogenic carbon pulses into the atmosphere over 100 years was compared between biomass use for energy and its business‐as‐usual decomposition in agricultural, forestry, or landfill sites. Bioenergy use increased atmospheric CO2 load in all cases, resulting in a 100GWPbCO2 (units of g CO2e/g biomass CO2 released) of 0.003 for the fast‐decomposing agricultural residues to 0.029 for the slow, 0.084–0.625 for forest residues, and 0.368–0.975 for landfill lignocellulosic biomass. In comparison, carbon emissions from fossil fuels have a 100GWP of 1.0 g (CO2e/g fossil CO2). The fast decomposition rate and the corresponding low 100GWPbCO2 values of agricultural residues make them a more climate‐friendly feedstock for bioenergy production relative to forest residues and landfill lignocellulosic biomass. This study shows that CO2 released from the combustion of bioenergy or biofuels made from residual biomass has a greenhouse gas footprint that should be considered in assessing climate impacts.

Bi-directional Monte-Carlo modelling of solar-induced chlorophyll fluorescence images for 3D vegetation canopies in the DART model

Remote sensing (RS) of solar-induced chlorophyll fluorescence (SIF) has a great potential for monitoring plant photosynthetic activity. Radiative transfer models (RTM) are essential to better interpret and extract information from SIF signals. DART is one of the most comprehensive and accurate 3D RTMs. Its standard mode DART-FT simulates SIF using a discrete ordinates method but is not adapted to large landscapes due to computational constraints. DART-Lux, the new mode based on a bi-directional path tracing algorithm, greatly improves DART computational efficiency for simulating images. This paper presents the theory of a novel SIF modelling algorithm in DART-Lux. We verified its accuracy with DART-FT and the SCOPE model for three types of canopies: turbid medium, maize field and forest. DART-Lux closely matches DART-FT (relative difference < 2%) with much better computational efficiency depending on the scene complexity, number of spectral bands and needed accuracy. For example, simulation time is reduced by a factor of ≈48, and memory usage by ≈50 for a maize field at 1 cm resolution. It allowed to simulate SIF images of large scenes as the 3×3km2 Ripperdan agricultural site that DART-FT could not simulate. The new SIF modelling algorithm opens new horizons for RS studies of large and complex landscapes. It is available as part of released DART versions (v1152 onwards) (https://dart.omp.eu/).

Selenium Uptake from Livestock Pasture Extremely Enriched in Selenium, Molybdenum and Uranium: A Field and X-ray Absorption Study

The agricultural soils of West Limerick, Ireland, contain very localised, extremely high natural Se concentrations that reach levels that are very toxic to grazing livestock. The Carboniferous shales that formed in anoxic deep-water marine environments are the source of the selenium, which, along with the other redox-sensitive elements of molybdenum, uranium, arsenic and vanadium, were mobilised and reprecipitated in post-glacial anoxic marshes. The result has been a history of selenosis and molybdenosis in livestock in this important dairy province. Soils collected at 10–20 cm from five different agricultural sites were analysed, and all yielded concentrations greatly in excess of the safe Se limits of 3–10 mg kg−1; the highest value recorded was 1265.8 mg kg−1 Se. The highest recorded value for Mo in these soils was 1627.5 mg kg−1, and for U, 658.8 mg kg−1. There was a positive correlation between Se, Mo U and organic matter in the soils. Analysis of non-accumulator pasture grasses (Lolium perenne (perennial ryegrass), Festuca arundinacea (tall fescue), Dactylis glomerata (cocksfoot) and Phleum pretense (timothy grass)) revealed the shoot/leaf to contain up to 78.05 mg kg−1 Se while Trifolium repens (white clover) leaves contained 296.15 mg kg−1 Se. An in situ growing experiment using the Se accumulator species Brassica oleracea revealed 971.2 mg kg−1 Se in the leaves of premier kale, which also contained 1000.4 mg kg−1 Mo. Translocation factors (TFs) were generally higher for Mo than Se across all plant species. Combined X-ray absorption near edge spectroscopy (XANES) with micro-X-ray fluorescence (μ-XRF) showed the Se was present in the soil predominantly as the reduced immobile phase, elemental Se (Se0), but also as bioavailable organoselenium species, mainly selenomethionine (SeMet). SeMet was also the main species identified within both the Se non-accumulator and Se accumulator plants. The Se soil–plant system in West Limerick is dominated by SeMet, and uptake into the cattle pasture results in selenosis in the grazing dairy herds. The hyperaccumulating Brassica oleracea species could be used to extract both the Se and Mo to reduce the toxicity of the blighted fields.

Heavy metal(loid) effect on multi-biomarker responses in apex predator: Novel assays in the monitoring of white stork nestlings

The goal of the present study was to investigate differences in biomarker responses related to metal(loid)s in white stork (Ciconia ciconia) nestling's blood from continental Croatia. To achieve this, a battery of biomarkers that can be affected by environmental pollutants, including metal(loid)s, was assessed (esterase activity, fluorescence–based oxidative stress biomarkers, metallothionein levels, glutathione–dependent enzyme activity). The research was conducted during the white stork breeding season in diverse areas (a landfill, industrial and agricultural sites, and an unpolluted area). White storks' nestlings near the landfill exhibited reduced carboxylesterase (CES) activity, elevated glutathione (GSH) concentration, as well as high Pb content in the blood. Increased As and Hg concentrations in blood were attributable to environmental contamination in agricultural area and an assumed unpolluted area, respectively. Furthermore, agricultural practices appeared to affect CES activity, as well as elevate Se levels. In addition to the successful implementation of biomarkers, present research showed that agricultural areas and a landfill are areas with increased metal(loid) levels possibly causing adverse effects on the white storks. This first–time heavy metal and metalloid analyses in the white stork nestlings from Croatia point to the necessary monitoring and future assessments of pollution impact to prevent irreversible adverse effects.

Impact of Nonconventional Selection by Insecticides on Susceptibility of the Southern House Mosquito,Culex quinquefasciatus

Mosquitoes are an important target of pest control as they vector pathogens that are associated with many debilitating human diseases. Given that mosquitoes have been selected with insecticides for over 100 years, much is known about the development of insecticide resistance associated with targeted application against populations of these insects. However, off-target selection by applications of insecticides in agricultural and residential sites also impacts development of insecticide resistance and is understudied. Similarly, the impact of selecting one life stage of mosquitoes on the insecticide susceptibility of different life stages is largely unknown. Here, we show that susceptibility to chlorantraniliprole, which is applied in rice (Oryza sativa) and sugarcane (Saccharum officinarum) fields in Louisiana, decreased (5.7- to 12-fold) in populations of Culex quinquefasciatus collected from near these fields compared with a reference field strain. In addition, application of bifenthrin by commercial application on an individual residence increased the resistance frequencies to bifenthrin in 5 nearby residential sites. These increased frequencies of resistance, as measured with diagnostic concentrations of bifenthrin, were highly correlated (R2 = 0.92) between larvae and adults, suggesting that selection of adults also confers resistance to larvae. Finally, esterase activities and bifenthrin susceptibilities were moderately correlated (R2 = 0.4 for larvae and 0.52 for adults), suggesting that multiple mechanisms (including metabolism by esterases) were associated with the observed resistance. Results from this study suggest that nonconventional selection by insecticides is a variable to consider when developing management strategies for populations of Cx. quinquefasciatus.