Уточнить поиск
Результаты 1-10 из 41
Evaluation of stabilizing material and stabilization efficiency through comparative study of toxic heavy metal transfer between corn and peanut grown in stabilized field soil
2021
Lee, Yonghyeon | Cui, Mingcan | Son, Younggyu | Ma, Junjun | Han, Zhengchang | Khim, Jeehyeong
Soil contaminated with toxic heavy metals (THMs) was stabilized by adding a combination of waste resources in 7.0 wt%, including coal-mine drainage sludge, waste cow bone, and steelmaking slag, in the ratio of 5:35:60. Subsequently, corn and peanut were cultivated in treated soil to investigate the effects of the waste resources on THM mobility in soil and translocation to plants. Sequential extraction procedures (SEP) was used to analyze mobile phase THMs which could be accumulated in the plants. SEP shows that mobile Pb, Cd, Cu, Zn, Ni, Cr, and As were reduced by 8.48%, 29.22%, 18.85%, 21.66%, 4.58%, 62.78%, and 20.01%, respectively. The bioaccumulation of THMs was clearly hindered by stabilization; however, the increment in the amount of immobile-phase THMs and change in the amount of translocated THMs was not proportional. The corn grains grown above the soil surface were compared with the peanut grains grown beneath the soil surface, and the results indicating that the efficiency of stabilization on THM translocation may not depend on the contact of grain to soil but the nature of plant. Interestingly, the results of bioaccumulation with and without stabilization showed that the movement of some THMs inside the plants was affected by stabilization.
Показать больше [+] Меньше [-]Nitrous oxide emission and sweet potato yield in upland soil: Effects of different type and application rate of composted animal manures
2021
Ruangcharus, Chuanpit | Kim, Sung Un | Yoo, Ga-young | Choi, Eun-Jung | Kumar, Sandeep | Kang, Namgoo | Hong, Chang Oh
The aims of this study were to determine type and application rate of composted animal manure to optimize sweet potato yield relative to N₂O emissions from upland soils. To this end, the study was conducted on upland soils amended with different types and rates of composted animal manure and located at two geographically different regions of South Korea. Field trials were established at Miryang and Yesan in South Korea during the sweet potato (Ipomoea batatas) growing season over 2 years: 2017 (Year 1) and 2018 (Year 2). Three composted animal manures (chicken, cow, and pig) were applied at the rates of 0, 10, and 20 Mg ha⁻¹ to upland soils in both locations. In both Years and locations, manure type did not affected significantly cumulative N₂O emissions from soil during the sweet potato growing season or the belowground biomass of sweet potato. However, application rate of animal manures affected significantly the cumulative N₂O emission, nitrogen (N) in soil, and belowground biomass of sweet potato. An increase in cumulative N₂O emission with application rates of animal manures was related to total N and inorganic N concentration in soil. The belowground biomass yield of sweet potato but also the cumulative N₂O emission increased with increasing application rate of composted animal manures up to 7.6 and 16.0 Mg ha⁻¹ in Miryang and Yesan, respectively. To reduce N₂O emission from arable soil while increasing crop yield, composted animal manures should be applied at less than application rate that produce the maximum belowground biomass of sweet potato.
Показать больше [+] Меньше [-]Spatial distribution of heavy metal contamination in mollisol dairy farm
2020
Qi, Zheng | Gao, Xi | Qi, Yue | Li, Jinlong
To accurately visualize the spatial distribution of heavy metal pollution and provide basic information on soil remediation in dairy farm, Geographic Information System (GIS) is used for optimization of sample collection and data analysis. Based on GIS technology, dairy manure, 10 cm-depth surface soil, 50 cm-depth sub soil, and surface water samples were collected from dairy farm in Dulbert Mongolian Autonomous County, Daqing City, Heilongjiang Province in China. The spatial distribution and assessment of heavy metals were performed by using GIS inverse distance weighted interpolation and pollution index method. The single factor pollution index value of As element in the soil was found to indicate the class of extreme contamination, whereas Ni in both surface water inside and outside the farm, and Sb in the cow drinking water were assigned to the level of moderate contamination. The comprehensive pollution index implied serious contamination for soil samples, slight contamination for water samples and safety for manure samples, respectively. Comprehensive score for heavy metal elements followed the orders of As>Zn>Cr>Ni>Cu>Pb>Cd>Hg. The horizontal pollution that mainly occurred in the middle and east regions was increased from north to south, and west to east district. Historically, the dairy farm belonged to heavily polluted saline-alkali soil, where the heavy metals might enter the food chain through transportation from soil to water, the cows, and eventually to the milk and human body. Visualizing spatial distribution of heavy metal contamination by using GIS technology will be of significance to provide useful information for soil remediation of dairy farm.
Показать больше [+] Меньше [-]Metal exposure in cows grazing pasture contaminated by iron industry: Insights from magnetic particles used as tracers
2016
Ayrault, Sophie | Catinon, Mickaël | Boudouma, Omar | Bordier, Louise | Agnello, Gregory | Reynaud, Stéphane | Tissut, Michel
Magnetic particles (MP) emitted by an iron smelter were used to investigate the exposure of cows grazing on a grassland polluted by these MP and by large amounts of potentially toxic elements (PTE). The morphology as well as the chemical composition of the MP separated from cow dung were studied. Large amounts of typical MP were found (1.1 g kg−1 dry weight) in the cow dung sampled from the exposed site, whereas these particles were absent from the reference unpolluted site. The ingested MP were mainly technogenic magnetic particles (TMP) emitted by the smelter. Considering the MP concentration in the grazed grass on the exposed site, it was concluded that cows absorb the MP not only from the grass but also from the soil surface. The results of a mild acidic leaching of the MP suggested that the particles were possibly submitted to a superficial dissolution in the abomasum, pointing at a potential route of transfer of the PTE originating from the TMP and leading into food chains. TMP were only a small part of the anthropogenic contamination having affected the soil and the dung. However, due to their unequivocal signature, TMP are a powerful tracer of the distribution of PTE in the different compartments constituting the food chains and the ecosystems. Furthermore, the measurement of the particle sizes gave evidence that a noticeable proportion of the MP could enter the respiratory tract.
Показать больше [+] Меньше [-]Determinants of the exposure of Eurasian griffon vultures (Gyps fulvus) to fluoroquinolones used in livestock: The role of supplementary feeding stations
2022
Herrero-Villar, Marta | Mateo-Tomás, Patricia | Sánchez-Barbudo, Inés S. | Camarero, Pablo R. | Taggart, Mark A. | Mateo, Rafael
Veterinary pharmaceuticals, including antibiotics, are emerging contaminants of concern worldwide. Avian scavengers are exposed to pharmaceuticals through consumption of livestock carcasses used for feeding wildlife for conservation purposes at supplementary feeding stations. Here we tested the hypothesis that griffon vultures (Gyps fulvus) would be more exposed to antibiotics (i.e., quinolones) when feeding on livestock carcasses from intensive farming than when they rely on carcasses from extensive farming or wild animals. We sampled 657 adult griffon vultures captured between 2008 and 2012. In addition, we sampled tissues from domestic livestock supplied at feeding stations in the study area between 2009 and 2019; pig (n = 114), sheep (n = 28), cow (n = 1) and goat (n = 2). Samples were analysed by liquid chromatography with electrospray ionization mass spectrometry (LC-ESI-MS). Quinolones were detected in plasma from 12.9% of the griffon vultures analysed. Quinolone prevalence in griffon vultures varied significantly among feeding stations but was also affected by the total amount of carcasses supplemented, especially the mass of pig carcasses. These results aligned with a 21.1% quinolone prevalence in pig carcasses sampled at feeding stations, wherein enrofloxacin and ciprofloxacin levels of up to 3359 ng/g and 1550 ng/g, respectively, were found. Given enrofloxacin pharmacokinetics in pig tissues, 5.3% of the analysed pigs may have died no more than one day after treatment. Quinolone presence in vultures was negatively associated with blood lead levels, which mostly originates from lead ammunition and indicates a higher consumption of game animal carcasses. Carcass disposal for feeding avian scavengers must always assess and manage the risks posed by veterinary pharmaceuticals, especially when livestock provided may have died soon after treatment.
Показать больше [+] Меньше [-]Regioselective hydroxylation of carbendazim by mammalian cytochrome P450: A combined experimental and computational study
2022
Lv, Xia | Li, Jing-Xin | Wang, Jia-Yue | Tian, Xiang-Ge | Feng, Lei | Sun, Cheng-Peng | Ning, Jing | Wang, Chao | Zhao, Wen-Yu | Li, Ya-Chen | Ma, Xiao-Chi
Carbendazim (CBZ), a broad-spectrum pesticide frequently detected in fruits and vegetables, could trigger potential toxic risks to mammals. To facilitate the assessment of health risks, this study aimed to characterize the cytochrome P450 (CYPs)-mediated metabolism profiles of CBZ by a combined experimental and computational study. Our results demonstrated that CYPs-mediated region-selective hydroxylation was a major metabolism pathway for CBZ in liver microsomes from various species including rat, mouse, minipig, dog, rabbit, guinea pig, monkey, cow and human, and the metabolite was biosynthesized and well-characterized as 6-OH-CBZ. CYP1A displayed a predominant role in the region-selective hydroxylation of CBZ that could attenuate its toxicity through converting it into a less toxic metabolite. Meanwhile, five other common pesticides including chlorpyrifos-methyl, prochloraz, chlorfenapyr, chlorpyrifos, and chlorothalonil could significantly inhibit the region-selective hydroxylation of CBZ, and consequently remarkably increased CBZ exposure in vivo. Furthermore, computational study clarified the important contribution of the key amino acid residues Ser122, and Asp313 in CYP1A1, as well as Asp320 in CYP1A2 to the hydroxylation of CBZ through hydrogen bonds. These results would provide some useful information for the metabolic profiles of CBZ by mammalian CYPs, and shed new insights into CYP1A-mediated metabolic detoxification of CBZ and its health risk assessment.
Показать больше [+] Меньше [-]Synergistic effects of compost, cow bile and bacterial culture on bioremediation of hydrocarbon-contaminated drill mud waste
2020
Osei-Twumasi, Daniel | Fei-Baffoe, Bernard | Anning, Alexander Kofi | Danquah, Kwabena Owusu
Bioremediation has gained global prominence as an effective method for treating hydrocarbon-contaminated drill mud waste (HCDW). However, the problem of low nutrient content, bioavailability and microbial presence remain largely unresolved. In this study, the synergistic effects of compost, cow bile and bacterial culture on the degradation rate of HCDW was investigated. A homogenized HCDW sample (80 kg) obtained from 25 different drill mud tanks was divided into 20 portions (4 kg each) and each adjusted to 1.4% nitrogen content + 20 ml cow bile (i.e., basic treatment). Pure cultures of Brevibacterium casei (Bc) and Bacillus zhangzhouensi (Bz) and their mixture (BcBz) were subsequently added to 12 of the amended HCDW (basic) to undergo a 6-week incubation. A portion of the unamended HCDW (2 kg) was used as control. Initial pH, electrical conductivity and surface tension values of the HCDW were 8.83, 2.34 mS/cm and 36.5 mN/m, respectively. Corresponding values for total petroleum hydrocarbon (TPH), total nitrogen and total plate count bacteria were 165 g/kg, 0.04% and 4.4 × 10² cfu/ml. The treatments led to a substantial reduction in TPH (p < 0.05) while the control had no significant effect (p > 0.05). TPH reduction after the experimental period occurred in the order: basic + BcBz (99.7%) > basic + Bz (99.5%) > basic + Bc (99.2%) > basic (95.2%) > control (0.06%). Multiple regression analysis revealed significant effect of total plate count, pH, CN ratio and electrical conductivity (R² = 0.87, p = 0.05) on the degradation of TPH in the HCDW. The study demonstrates strong interactive effects of compost, cow bile and bacteria culture on the remediation of HCDW, which can be applied to boost the efficiency of the bioremediation technique.
Показать больше [+] Меньше [-]Remote sensing and in situ measurements of methane and ammonia emissions from a megacity dairy complex: Chino, CA
2017
Leifer, Ira | Melton, Christopher | Tratt, David M. | Buckland, Kerry N. | Clarisse, Lieven | Coheur, Pierre | Frash, Jason | Gupta, Manish | Johnson, Patrick D. | Leen, J Brian | Van Damme, Martin | Whitburn, Simon | Yurganov, Leonid
Methane (CH4) and ammonia (NH3) directly and indirectly affect the atmospheric radiative balance with the latter leading to aerosol generation. Both have important spectral features in the Thermal InfraRed (TIR) that can be studied by remote sensing, with NH3 allowing discrimination of husbandry from other CH4 sources. Airborne hyperspectral imagery was collected for the Chino Dairy Complex in the Los Angeles Basin as well as in situ CH4, carbon dioxide (CO2) and NH3 data. TIR data showed good spatial agreement with in situ measurements and showed significant emissions heterogeneity between dairies. Airborne remote sensing mapped plume transport for ∼20 km downwind, documenting topographic effects on plume advection. Repeated multiple gas in situ measurements showed that emissions were persistent on half-year timescales. Inversion of one dairy plume found annual emissions of 4.1 × 10⁵ kg CH4, 2.2 × 10⁵ kg NH3, and 2.3 × 10⁷ kg CO2, suggesting 2300, 4000, and 2100 head of cattle, respectively, and Chino Dairy Complex emissions of 42 Gg CH4 and 8.4 Gg NH3 implying ∼200k cows, ∼30% more than Peischl et al. (2013) estimated for June 2010. Far-field data showed chemical conversion and/or deposition of Chino NH3 occurs within the confines of the Los Angeles Basin on a four to six h timescale, faster than most published rates, and likely from higher Los Angeles oxidant loads. Satellite observations from 2011 to 2014 confirmed that observed in situ transport patterns were representative and suggests much of the Chino Dairy Complex emissions are driven towards eastern Orange County, with a lesser amount transported to Palm Springs, CA. Given interest in mitigating husbandry health impacts from air pollution emissions, this study highlights how satellite observations can be leveraged to understand exposure and how multiple gas in situ emissions studies can inform on best practices given that emissions reduction of one gas could increase those of others.
Показать больше [+] Меньше [-]Bone-derived biochar improved soil quality and reduced Cd and Zn phytoavailability in a multi-metal contaminated mining soil
2021
Azeem, Muhammad | Ali, Amjad | Arockiam Jeyasundar, Parimala Gnana Soundari | Li, Yiman | Abdelrahman, Hamada | Latif, Abdul | Li, Ronghua | Basta, Nicholas | Li, Gang | Shaheen, Sabry M. | Rinklebe, Jörg | Zhang, Zenqqiang
Reusing by-products such as cow bones in agriculture can be achieved thorough pyrolysis. The potential of bone-derived biochar as a promising material for metals immobilization in contaminated mining soils has not yet been sufficiently explored. Therefore, cow bones were used as biochar feedstock were pyrolyzed at 500 °C (CBL) and 800 °C (CBH) and. The two biochars were applied to a mine contaminated soil at 0 (control), 2.5, 5 and 10%, w/w, dosages; then, the soils were incubated and cultivated by maize in the greenhouse. Cadmium (Cd) and zinc (Zn) bioavailability and their sequentially extracted fractions (acid soluble, reducible, oxidizable, and residual fraction), soil microbial function, and plant health attributes were analyzed after maize harvesting. Bone-derived biochar enhanced the content of dissolved organic carbon (up to 74%), total nitrogen (up to 26%), and total phosphorus (up to 27%) in the soil and improved the plant growth up to 55%, as compared to the control. The addition of CBL altered the acid soluble fraction of both metals to the residual fraction and, thus, reduced the content of Zn (55 and 40%) and Cd (57 and 67%) in the maize roots and shoots, respectively as compared to the control. The CBL enhanced the β-glucosidase (51%) and alkaline phosphatase activities (71%) at the lower doses (2.5–5%) as compared to control, while the activities of these enzymes decreased with the higher application doses. Also, CBL improved the antioxidants activity and maize growth at the 2.5–5% application rate. However, the activity of the dehydrogenase significantly decreased (77%), particularly with CBH. We conclude that CBL, applied at 2.5–5% dose, can be utilized as a potential low cost and environmental friendly amendment for stabilization of toxic metals in contaminated mining soils and producing food/feed/biofuel crops with lower metal content.
Показать больше [+] Меньше [-]Validation and application of quantitative PCR assays using host-specific Bacteroidales genetic markers for swine fecal pollution tracking
2017
Fan, Lihua | Shuai, Jiangbing | Zeng, Ruoxue | Mo, Hongfei | Wang, Suhua | Zhang, Xiaofeng | He, Yongqiang
Genome fragment enrichment (GFE) method was applied to identify host-specific bacterial genetic markers that differ among different fecal metagenomes. To enrich for swine-specific DNA fragments, swine fecal DNA composite (n = 34) was challenged against a DNA composite consisting of cow, human, goat, sheep, chicken, duck and goose fecal DNA extracts (n = 83). Bioinformatic analyses of 384 non-redundant swine enriched metagenomic sequences indicated a preponderance of Bacteroidales-like regions predicted to encode metabolism-associated, cellular processes and information storage and processing. After challenged against fecal DNA extracted from different animal sources, four sequences from the clone libraries targeting two Bacteroidales- (genes 1–38 and 3–53), a Clostridia- (gene 2–109) as well as a Bacilli-like sequence (gene 2–95), respectively, showed high specificity to swine feces based on PCR analysis. Host-specificity and host-sensitivity analysis confirmed that oligonucleotide primers and probes capable of annealing to select Bacteroidales-like sequences (1–38 and 3–53) exhibited high specificity (>90%) in quantitative PCR assays with 71 fecal DNAs from non-target animal sources. The two assays also demonstrated broad distributions of corresponding genetic markers (>94% positive) among 72 swine feces. After evaluation with environmental water samples from different areas, swine-targeted assays based on two Bacteroidales-like GFE sequences appear to be suitable quantitative tracing tools for swine fecal pollution.
Показать больше [+] Меньше [-]