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A new pseudo-partition coefficient based on a weather-adjusted multicomponent model for mushroom uptake of pesticides from soil 全文
2020
Li, Zijian
In this study, a weather-based multicomponent model was developed based on the unique biostructures and metabolic processes of mushrooms to evaluate their uptake of pesticides from soils, and the effects of temperature and relative humidity on the bioaccumulation of pesticides in mushrooms was comprehensively quantified. Additionally, a new pseudo-partition coefficient between mushrooms and soils was introduced to assess the impacts of different physiochemical properties on the pesticide uptake process. The results indicate that, in general, the pseudo-partition coefficient increases as the relative humidity increases for both the air and soil according to Fick’s law of gas diffusion and the spatial competition of molecules, respectively. Meanwhile, the effect of temperature on the pesticide bioaccumulation process is more complex. For most pesticides (e.g., atrazine), the pseudo-partition coefficient that was computed from the transpiration component had a maximum value at a specific temperature due to the temperature dependency of the transpiration and biodegradation processes. For some pesticides (e.g., ethoprophos), the pseudo-partition coefficient of the air-deposition component had a maximum value at a certain temperature that was caused by the ratio of the soil–air internal transfer energy and degradation activation energy of the pesticide. It was also concluded that for relatively low-volatility pesticides, transpiration dominated the bioaccumulation process; this was mainly determined from the pesticide water solubility. For nonbiodegradable pesticides (e.g., lindane), the computed coefficient values were relatively low due to their insolubility in water, which inhibits bioaccumulation in mushrooms and is one of the main reasons for their long-term persistence in soils.
显示更多 [+] 显示较少 [-]Accumulation and spatial distribution of copper and nutrients in willow as affected by soil flooding: A synchrotron-based X-ray fluorescence study 全文
2019
Cao, Yini | Ma, Chuanxin | Zhang, Jianfeng | Wang, Shufeng | White, Jason C. | Chen, Guangcai | Xing, Baoshan
Copper (Cu) induced phytotoxicity has become a serious environmental problem as a consequence of significant metal release through anthropogenic activity. Understanding the spatial distribution of Cu in plants such as willow is essential to elucidate the mechanisms of metal accumulation and transport in woody plants, particularly as affected by variable environment conditions such as soil flooding. Using synchrotron-based X-ray fluorescence (μ-XRF) techniques, the spatial distribution of Cu and other nutrient elements were investigated in roots and stems of Salix (S.) integra exposed to 450 mg kg⁻¹ Cu under non-flooded (NF)/flooding (F) conditions for 90 d. S. integra grown in the F condition exhibited significant higher tolerance index (TI, determined by the ratio of total biomass in Cu treatments to control) (p < 0.05) than that in the NF condition, indicating soil flooding alleviated Cu toxicity to willow plants. The μ-XRF revealed that Cu was preferentially located in the root cap and meristematic zone of the root tips. Under the NF condition, the Cu intensity in the root epidermis was more highly concentrated than that of the F condition, suggesting the soil flooding significantly inhibited Cu uptake by S. integra. The pattern of the Cu spatial distribution in the S. integra stem indicated that the F condition severely reduced Cu transport via the xylem vessels as a consequence of decreasing the transpiration rate of leaves. To our knowledge, this is the first study to report the in vivo Cu distribution in S. integra in a scenario of co-exposure to the Cu and the soil flooding over a long period. The finding that Cu uptake varies significantly with flooding condition is relevant to the development of strategies for plants to detoxify the metals and to maintain the nutrient homeostasis.
显示更多 [+] 显示较少 [-]Transfer of antibiotics from wastewater or animal manure to soil and edible crops 全文
2017
Antibiotics are added to agricultural fields worldwide through wastewater irrigation or manure application, resulting in antibiotic contamination and elevated environmental risks to terrestrial environments and humans. Most studies focused on antibiotic detection in different matrices or were conducted in a hydroponic environment. Little is known about the transfer of antibiotics from antibiotic-contaminated irrigation wastewater and animal manure to agricultural soil and edible crops. In this study, we evaluated the transfer of five different antibiotics (tetracycline, sulfamethazine, norfloxacin, erythromycin, and chloramphenicol) to different crops under two levels of antibiotic-contaminated wastewater irrigation and animal manure fertilization. The final distribution of tetracycline (TC), norfloxacin (NOR) and chloramphenicol (CAP) in the crop tissues under these four treatments were as follows: fruit > leaf/shoot > root, while an opposite order was found for sulfamethazine (SMZ) and erythromycin (ERY): root > leaf/shoot > fruit. The growth of crops could accelerate the dissipation of antibiotics by absorption from contaminated soil. A higher accumulation of antibiotics was observed in crop tissues under the wastewater treatment than under manure treatment, which was due to the continual irrigation that increased adsorption in soil and uptake by crops. The translocation of antibiotics in crops mainly depended on their physicochemical properties (e.g. log Kow), crop species, and the concentrations of antibiotics applied to the soil. The levels of antibiotics ingested through the consumption of edible crops under the different treatments were much lower than the acceptable daily intake (ADI) levels.
显示更多 [+] 显示较少 [-]Canopy-level stomatal narrowing in adult Fagus sylvatica under O3 stress – Means of preventing enhanced O3 uptake under high O3 exposure? 全文
2015
Matyssek, R. | Baumgarten, M. | Hummel, U. | Häberle, K.-H. | Kitao, M. | Wieser, G.
Spatio-temporally consistent O3 doses are demonstrated in adult Fagus sylvatica from the Kranzberg Forest free-air fumigation experiment, covering cross-canopy and whole-seasonal scopes through sap flow measurement. Given O3-driven closure of stomata, we hypothesized enhanced whole-tree level O3 influx to be prevented under enhanced O3 exposure. Although foliage transpiration rate was lowered under twice-ambient O3 around noon by 30% along with canopy conductance, the hypothesis was falsified, as O3 influx was raised by 25%. Nevertheless, the twice-ambient/ambient ratio of O3 uptake was smaller by about 20% than that of O3 exposure, suggesting stomatal limitation of uptake. The O3 response was traceable from leaves across branches to the canopy, where peak transpiration rates resembled those of shade rather than sun branches. Rainy/overcast-day and nightly O3 uptake is quantified and discussed. Whole-seasonal canopy-level validation of modelled with sap flow-derived O3 flux becomes available in assessing O3 risk for forest trees.
显示更多 [+] 显示较少 [-]Effect of transpiration on plant accumulation and translocation of PPCP/EDCs 全文
2015
Dodgen, Laurel K. | Ueda, Aiko | Wu, Xiaoqin | Parker, David R. | Gan, Jay
The reuse of treated wastewater for agricultural irrigation in arid and hot climates where plant transpiration is high may affect plant accumulation of pharmaceutical and personal care products (PPCPs) and endocrine disrupting chemicals (EDCs). In this study, carrot, lettuce, and tomato plants were grown in solution containing 16 PPCP/EDCs in either a cool-humid or a warm-dry environment. Leaf bioconcentration factors (BCF) were positively correlated with transpiration for chemical groups of different ionized states (p < 0.05). However, root BCFs were correlated with transpiration only for neutral PPCP/EDCs (p < 0.05). Neutral and cationic PPCP/EDCs showed similar accumulation, while anionic PPCP/EDCs had significantly higher accumulation in roots and significantly lower accumulation in leaves (p < 0.05). Results show that plant transpiration may play a significant role in the uptake and translocation of PPCP/EDCs, which may have a pronounced effect in arid and hot climates where irrigation with treated wastewater is common.
显示更多 [+] 显示较少 [-]Water, heat, and airborne pollutants effects on transpiration of urban trees 全文
2011
Wang, Hua | Ouyang, Z. (Zhiyun) | Chen, Weiping | Wang, Xiaoke | Zheng, Hua | Ren, Yufen
Transpiration rates of six urban tree species in Beijing evaluated by thermal dissipation method for one year were correlated to environmental variables in heat, water, and pollutant groups. To sort out colinearity of the explanatory variables, their individual and joint contributions to variance of tree transpiration were determined by the variation and hierarchical partitioning methods. Majority of the variance in transpiration rates was associated with joint effects of variables in heat and water groups and variance due to individual effects of explanatory group were in comparison small. Atmospheric pollutants exerted only minor effects on tree transpiration. Daily transpiration rate was most affected by air temperature, soil temperature, total radiation, vapor pressure deficit, and ozone. Relative humidity would replace soil temperature when factors influencing hourly transpiration rate was considered.
显示更多 [+] 显示较少 [-]Combining sap flow and eddy covariance approaches to derive stomatal and non-stomatal O3 fluxes in a forest stand 全文
2010
Nunn, A.J. | Cieslik, S. | Metzger, U. | Wieser, G. | Matyssek, R.
Stomatal O3 fluxes to a mixed beech/spruce stand (Fagus sylvatica/Picea abies) in Central Europe were determined using two different approaches. The sap flow technique yielded the tree-level transpiration, whereas the eddy covariance method provided the stand-level evapotranspiration. Both data were then converted into stomatal ozone fluxes, exemplifying this novel concept for July 2007. Sap flow-based stomatal O3 flux was 33% of the total O3 flux, whereas derivation from evapotranspiration rates in combination with the Penman-Monteith algorithm amounted to 47%. In addition to this proportional difference, the sap flow-based assessment yielded lower levels of stomatal O3 flux and reflected stomatal regulation rather than O3 exposure, paralleling the daily courses of canopy conductance for water vapor and eddy covariance-based total stand-level O3 flux. The demonstrated combination of sap flow and eddy covariance approaches supports the development of O3 risk assessment in forests from O3 exposure towards flux-based concepts.
显示更多 [+] 显示较少 [-]Acropetal translocation of phenanthrene in wheat seedlings: Xylem or phloem pathway? 全文
2020
Due to the potential toxicity of polycyclic aromatic hydrocarbons (PAHs) to humans, the uptake and translocation of PAHs in food crops have gained much attention. However, it is still unclear whether phloem participates in the acropetal translocation of PAHs in plants. Herein, the evidence for acropetal translocation of phenanthrene (a model PAH) via phloem is firstly tested. Wheat (Triticum aestivum L.) new leaves contain significantly higher phenanthrene concentration than old leaves (P < 0.05), and the inhibitory effect on phenanthrene translocation is stronger in old leaves after abscisic acid and polyvinyl alcohol (two common transpiration inhibitors) application. Phenanthrene concentration in xylem sap is slightly higher than in phloem sap. Ring-girdling treatment can significantly reduce phenanthrene concentration in castor bean (Ricinus communis L.) leaves. Two-photon fluorescence microscope images indicate a xylem-to-phloem and acropetal phloem translocation of phenanthrene in castor bean stem. Therefore, phloem is involved in the acropetal translocation of phenanthrene in wheat seedlings, especially when the xylem is not mature enough in scattered vascular bundle plants. Our results provide a deeper understanding of PAH translocation in plants, which have significant implications for food safety and phytoremediation enhancement of PAH-contaminated soil and water.
显示更多 [+] 显示较少 [-]Climate change impacts the subsurface transport of atrazine and estrone originating from agricultural production activities 全文
2020
Barrios, Renys E. | Akbariyeh, Simin | Liu, Chuyang | Gani, Khalid Muzamil | Kovalchuk, Margarita T. | Li, Xu | Li, Yusong | Snow, Dan | Tang, Zhenghong | Gates, John | Bartelt-Hunt, Shannon L.
Climate change will impact soil properties such as soil moisture, organic carbon and temperature and changes in these properties will influence the sorption, biodegradation and leaching of trace organic contaminants to groundwater. In this study, we conducted a modeling case study to evaluate atrazine and estrone transport in the subsurface under current and future climate conditions at a field site in central Nebraska. According to the modeling results, in the future, enhanced evapotranspiration and increased average air temperature may cause drier soil conditions, which consequently reduces the biodegradation of atrazine and estrone in the water phase. On the other hand, greater transpiration rates lead to greater root solute uptake which may decrease the concentration of atrazine and estrone in the soil profile. Another consequence of future climate is that the infiltration and leaching rates for both atrazine and estrone may be lower under future climate scenarios. Reduced infiltration of trace organic compounds may indicate that lower trace organic concentrations in groundwater may occur under future climate scenarios.
显示更多 [+] 显示较少 [-]New Miscanthus hybrids cultivated at a Polish metal-contaminated site demonstrate high stomatal regulation and reduced shoot Pb and Cd concentrations 全文
2019
Rusinowski, Szymon | Krzyżak, Jacek | Clifton-Brown, John | Kane, Elaine | Mos, Michal | Webster, Richard | Sitko, Krzysztof | Pogrzeba, Marta
The increased bioeconomy targets for the biomass share of renewable energy production across Europe should be met using land unsuitable for food production. Miscanthus breeding programs targeted the production of plants with a diverse range of traits allowing a wider utilization of land resources for biofuel production without competing with arable crops. These traits include increasing tolerances to drought, chilling, and to metal(loid)s excess. Two novel Miscanthus hybrids, GNT41 and GNT34, were compared against Miscanthus x giganteus (Mxg) on metal-contaminated arable land in Poland. This study aimed at evaluating their yield, biomass quality and quantifying seasonal differences in photosynthetic and transpiration parameters. A secondary objective was to identify key physiological mechanisms underlying differences in metal accumulation between the investigated plants. The new hybrids produced a similar yield to Mxg (13–15 t ha−1 yr−1), had shorter shoots, higher Leaf Area Index and stem number. Based on gas exchange measurements, GNT34 exhibited isohydric (water-conserving) behavior. The stomatal response to light of the new hybrids was at least twice as fast as that of Mxg, a trait that is often associated with increased seasonal water use efficiency. This contributed to the almost 40% reduction in shoot Pb and Cd concentrations for the new hybrids as compared to Mxg. This suggested that promoting stomatal regulation in conjunction with improved water conservation may be a target for improving plants for wider use on metals contaminated land.
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