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Application of biomagnetic analysis technique using roadside trees for monitoring and identification of possible sources of atmospheric particulates in selected air pollution hotspots in Delhi, India
2021
Singh, Babita | Kaushik, Anubha
With increasing atmospheric pollution and health issues associated with size of the particulate matter, it has become important to look for techniques that may improve the monitoring resolution. Magnetic bio-monitoring of particulate matter has been used in recent years in some countries as an approach for better spatial resolution that provides proxy indicators for the measurements over large areas. Delhi, which is one of the most polluted cities of not just India, but the whole world, is still probing to understand the possible sources. The present magnetic biomonitoring study was therefore, carried across different land use areas in some air pollution hotspots of Delhi, using common roadside tree species Morus alba, Ficus religiosa, Ficus virens and Ficus benghalensis to understand the magnitude and nature of the particulate pollution, and possible sources by studying magnetic properties (Magnetic susceptibility, Frequency-dependent susceptibility, S-ratio, and SIRM) of the dust deposited on leaves. Mass specific magnetic susceptibility (10⁻⁸ m³ kg⁻¹) values were found to follow the order: Traffic intersection area (25.6–66.5) > Industrial area (25.4–41.3) > Residential area (13.2–30.1) > Institutional area serving as control (2.7–6.6). High magnetic susceptibility values indicated particulates with ferrimagnetic grains of anthropogenic or technogenic origin. Frequency-dependent Susceptibility indicated dominance of coarse multidomain (MD) and Pseudo Single Domain (PSD) +MD grains in industrial area and major traffic intersection. Average S ratio across all study sites ranged from 0.92 to 0.99 indicating presence of soft magnetic mineral with low coercivity. High SIRM values (10⁻⁵Am² kg⁻¹) from 58.1 to 862.3 suggested prevalence of magnetite dominating atmospheric particulates particularly in traffic intersection and industrial area, and to some extent in residential area. Morus alba and Ficus religiosa were found more suitable bio-monitors and the technique provided useful information on size, mineralogy and possible source of the particulates.
Afficher plus [+] Moins [-]Assessment of anticipated performance index of some deciduous plant species under dust air pollution
2020
Javanmard, Zeinab | Kouchaksaraei, Masoud Tabari | Hosseini, Seyed Mohsen | Pandey, Ashutosh Kumar
Green vegetation improvement is an economical strategy to mitigate dust air pollution. The anticipated performance index (API) is considered a main criterion to select the suitable plants of urban forests. API is calculated by taking air pollution tolerance index (APTI) and socio-economic and biological aspects into account. In the present work, API of four current deciduous tree species in urban areas of Iran was evaluated. The seedlings were soil-dusted by a dust simulator in plastic chambers at levels of 0, 300, 750, and 1500 μg/m³ at intervals of 1 week for 70 days. At 750 and 1500 μg/m³ dust concentrations (DCs), greatest dust collection capacity was observed with Morus alba and the lowest one with Melia azedarach. Increasing DC declined APTI of all species. At 750 μg/m³ DC, only Morus was tolerant, but at 1500 μg/m³ DC, this species and Melia were categorized as intermediate, and Celtis caucasica and Fraxinus rotundifolia as sensitive. Morus was assessed as a good performer under two higher DC. Celtis was recognized as a moderate under 750 μg/m³ DC and poor performer under 1500 μg/m³ DC. Thus, Celtis can be considered as a biomonitor for air quality or as sink for dust in high dusty areas because of its high capacity of dust deposition. At two higher DCs, Fraxinus and Melia showed very poor and poor performance; planting these species in high dust areas is not recommended. In contrast, Morus is the most suitable tree species for urban green spaces in dusty regions, due to its high dust collection capacity and high APTI and API values.
Afficher plus [+] Moins [-]The Soil Amendments to Improve the Efficiency of the Intercropping System of Pteris vittata and Morus alba
2018
Wan, Xiaoming | Yang, Junxing
Intercropping of arsenic (As) hyperaccumulator Pteris vittata and cash crop Morus alba could improve the As concentration in the hyperaccumulator but decrease As concentration in the intercropped crop. The effects of several amendments on the transfer of As were investigated to determine an enhancement strategy for the intercropping system of P. vittata and M. alba. Phosphorus, in the form of Ca(H₂PO₄)₂, promoted the release of As to the soil solution and apparently increased the As removal from the soil by 42% compared with the untreated variant. The addition of FeSO₄ and CaCO₃ decreased As concentration in the soil solution and the uptake of As by both plant species. The As levels in the mulberry leaves remained under the threshold limits of feedstuffs in China. Intercropping was confirmed as an applicable strategy to manage contaminated soil. Hence, under the condition that all treatments produced safe mulberry leaves, Ca(H₂PO₄)₂ was the appropriate amendment to achieve the highest As removal rate, whereas FeSO₄ could lower the risk of As to further migrate to another medium.
Afficher plus [+] Moins [-]Mulberry trees conserved soil and protected water quality in the riparian zone of the Three Gorges Reservoir, China
2016
Liu, Yun | Willison, J. H Martin | Wan, Pan | Xiong, Xing-zheng | Ou, Yang | Huang, Xiao-hui | Wu, Jingchun | Zhou, Hao | Xu, Qiao | Chen, Guohui | Xili, Yuanzi | Nie, Jiasheng
China's Sloping Land Conversion Program (SLCP) was designed to restore perennial plant cover on sloping land in western China, in part to protect the Three Gorges Reservoir (TGR). In this study, we examined use of white mulberry (Morus alba L.) in the SLCP to protect water quality and conserve soil. We established nine runoff monitoring plots divided among three categories (vegetable farming, fallow control, and mulberry plantation) on a bank of the Liangtan River situated at the western margin of the TGR. The land had been used previously by farmers for growing vegetables. We found that soil loss and surface water runoff were lowest in the mulberry plots and highest in the vegetable plots. We used inductively coupled plasma atomic emission spectroscopy (ICP-AES) to assess the concentration of selected heavy metal pollution indicators (Zn, Hg, As, Ni, Pb, Cr, Cd, and Cu) in the monitoring plot soils at the beginning of the experiment in May 2009. The heavy metals were assessed again at the end of the experiment in October 2012, and we found that the concentrations of these pollutants had been reduced in all fallow and mulberry plots, and to the greatest extent in the mulberry plots. We found that levels of Hg, Pb, and Cu increased in the vegetable plots. For these reasons, we conclude that riparian mulberry plantations are useful for reducing rapid runoff of storm water, conserving soil, and sequestering heavy metal pollutants in the TGR region.
Afficher plus [+] Moins [-]The response of mulberry trees after seedling hardening to summer drought in the hydro-fluctuation belt of Three Gorges Reservoir Areas
2013
Huang, Xiaohui | Liu, Yun | Li, Jiaxing | Xiong, Xingzheng | Chen, Yang | Yin, Xiaohua | Feng, Dalan
Interest has developed in the potential of mulberry (Morus alba), a woody perennial, for revegetating the hydro-fluctuation belt of the Three Gorges Reservoir due to its resistance to water-logging stress. To be useful, the trees must also be able to withstand dry conditions in summer when temperatures can be very high and droughts become severe quickly. Here, we report a study in which mulberry seedlings were grown in a greenhouse under a variety of simulated soil water conditions reflecting potential summer scenarios in the hydro-fluctuation belt of the Three Gorges Reservoir Area. We compared the responses of two pretreatment groups of mulberry seedlings to different levels of drought stress. The pretreatment groups differed with respect to drought hardening: the daily-managed (DM) group had relative soil moisture held constant in the range 70-80 %, while the drought-hardened (DH) group had relative soil moisture held constant at 40-50 %. Following the month-long pretreatment of seedlings, the two groups of young trees (DM and DH) were then respectively subjected to three levels of drought stress for a month: normal watering, moderate drought stress, and severe drought stress. A series of measurements comparing the physiological status of the plants in the two groups were then made, and the following results were obtained: (1) As drought stress increased, the heights, base diameters, root surface areas, photosynthetic rates (Pn), stomatal conductances (Gs), and transpiration rates (Tr) of the mulberry trees in both groups (DM and DH) decreased significantly, while the specific root area and abscisic acid (ABA) contents had increasing trends. Root activity and instantaneous water use efficiency of mulberry trees in both groups (DM and DH) were all raised under drought stress conditions than under normal watering, but the root/shoot ratio and leaf water potential were lowered. (2) At the same level of soil water content, the heights, base diameters, root/shoot ratios, root surface areas, specific root areas, photosynthetic rates (Pn), stomatal conductances (Gs), and transpiration rates (Tr) of the young mulberry trees in the DH were all significantly higher than those of the control group (DM). Leaf water potential, instantaneous water use efficiency, and abscisic acid content of DH were all significantly lower than DM. Under different degrees of drought stress, the growth of mulberry trees will be inhibited, but the trees can respond to the stress by increasing the root absorptive area and enhancing capacity for water retention. Mulberry trees demonstrate strong resistance to drought stress, and furthermore drought resistance can be improved by drought hardening during the seedling stage.
Afficher plus [+] Moins [-]Accumulation of Cd by three forage mulberry (Morus atropurpurea Roxb.) cultivars in heavy metal–polluted farmland: a field experiment
2021
Jiang, Yongbing | Jiang, Shimeng | Huang, Renzhi | Wang, Ming | Cao, Hui | Li, Zhangbao
A 3-year field experiment was conducted to evaluate the accumulation ability of 3 forage mulberry (Morus atropurpurea Roxb.) varieties (Guisangyou 62, Guisangyou 12, Yuesang 11) for Cadmium (Cd). The results showed that the shoot biomass of forage mulberry could reach to 64.51~69.58 t/ha in 2018. The total production of Guisangyou 12 was the highest among the tested 3 cultivars in each year. However, the biomass of the 3 varieties displayed without significant differences at every sampling time. In addition, the concentrations of Cd in the roots of the 3 mulberry cultivars were higher than those in the corresponding shoots in 2018. But in 2019, the Cd content in roots was near to that of shoots. The Cd concentrations in the roots of the forage mulberry showed Guisangyou 62 > Yuesang 11 > Guisangyou 12. And the Cd concentrations in shoots of all the 3 tested forage mulberry varieties were less than 1 mg/kg, meeting the hygienical standard for feeds (China). Though the 3 forage mulberry varieties were not hyperaccumulators for Cd, they could be used as alternative plants to make use of the Cd-polluted (< 1.0 mg/kg) paddy soils.
Afficher plus [+] Moins [-]Morus alba leaf extract mediates neuroprotection against glyphosate-induced toxicity and biochemical alterations in the brain
2017
Rebai, Olfa | Belkhir, Manel | Boujelben, Adnen | Fattouch, Sami | Amri, Mohamed
Recent studies demonstrate that glyphosate exposure is associated with oxidative stress and some neurological disorders such as Parkinson’s pathology. Therefore, phytochemicals, in particular phenolic compounds, have attracted increasing attention as potential agents for neuroprotection. In the present study, we investigate the impact of glyphosate on the rat brain following i.p. injection and the possible molecular target of neuroprotective activity of the phenolic fraction from Morus alba leaf extract (MALE) and its ability to reduce oxidative damage in the brain. Wistar rats from 180 to 240 g were i.p. treated with a single dose of glyphosate (100 mg kg⁻¹ b.w.) or MALE (100 μg mL⁻¹ kg⁻¹ b.w.) for 2 weeks. Brain homogenates were used to evaluate neurotoxicity induced by the pesticide. For this, biochemical parameters were measured. Data shows that MALE regulated oxidative stress and counteracted glyphosate-induced deleterious effects and oxidative damage in the brain, as it abrogated LDH, protein carbonyls, and malonyldialdehyde. MALE also appears to be able to scavenge H₂O₂ levels, maintain iron and Ca²⁺ homeostasis, and increase SOD activity. Thus, in vivo results showed that mulberry leaf extract is a potent protector against glyphosate-induced toxicity, and its protective effect could result from synergism or antagonism between the various bioactive phenolic compounds in the acetonic fraction from M. alba leaf extract.
Afficher plus [+] Moins [-]Prospects for cultivating white mulberry (Morus alba) in the drawdown zone of the Three Gorges Reservoir, China
2013
Liu, Yun | Willison, J. H Martin
Restoration of vegetation is the most viable management approach for restoring ecological functions in the drawdown zone (hydro-fluctuation belt) of the Three Gorges Reservoir. The selection of plants for this purpose is therefore critically important. Most indigenous plants are not adapted, however, to the counter-seasonal fluctuation of water levels and rapid changes of up to 30 m in water depth that characterize the management of the reservoir. As a result, the reservoir drawdown zone tends to be vegetation deficient. Mulberry (Morus alba L.) has attracted attention as a suitable woody plant for restoring woody vegetation because of its strong adaptation to environmental stresses and the finding that it survives up to 7 m of flooding in parts of the drawdown zone. Comprehensive evaluation of research is therefore required in order to provide guidance for the rational use of mulberry in vegetation restoration strategies for the drawdown zone. Knowledge of the physiology of mulberry adaptation to stress is reviewed here, along with a detailed review of the ecology and agricultural benefits and limitations of mulberry in the context of the Three Gorges Reservoir. It is proposed that a cultivation model for mulberry plants based on ecological principles should be adopted for use within the drawdown zone and that a wider range of biophysical and socio-economic research to develop this model further should be conducted in the future.
Afficher plus [+] Moins [-]The suitability of growing mulberry (Morus alba L.) on soils consisting of urban sludge composted with garden waste: a new method for urban sludge disposal
2019
Si, Liqing | Peng, Xiawei | Zhou, Jinxing
Efficient disposal of urban sewage sludge, material that typically contains high concentrations of heavy metals, has become a significant concern worldwide. The empirical purpose of the current study is to investigate physical and chemical parameters of composted sludge and garden waste at different ratios. Results reveal that nutrient content has significantly increased after the application of composts as compared to the controlled sample. Composting garden waste with sewage sludge at a 1:1 ratio promoted plant growth and gradually showed superiority in the later period. The maximum plant height, total biomass, and crown width of mulberry trees increased by 12.1, 33.5, and 45.7%, respectively, compared with the control treatment. The bound to organic matter of Hg, Cr, and Pb in the sewage sludge increased after composting with garden waste, and the mulberry exhibited a high ability to accumulate Ni and Cd from the soil. Conclusively, compared to using the two soil mediums separately, composting garden waste and sewage sludge together is beneficial for soil improvement and vegetation growth.
Afficher plus [+] Moins [-]Health risk assessment from contaminated foodstuffs: a field study in chromite mining-affected areas northern Pakistan
2016
Nawab, Javed | Li, Gang | K̲h̲ān, Sardār | Sher, Hassan | Aamir, Muhammad | Shamshad, Isha | Khan, Anwarzeb | Khan, Muhammad Amjad
This study aimed to investigate the potential health risk associated with toxic metals in contaminated foodstuffs (fruits, vegetables, and cereals) collected from various agriculture fields present in chromite mining-affected areas of mafic and ultramafic terrains (northern Pakistan). The concentrations of Cr, Ni, Zn, Cd, and Pb were quantified in both soil and food samples. The soil samples were highly contaminated with Cr (320 mg/kg), Ni (108 mg/kg), and Cd (2.55 mg/kg), which exceeded their respective safe limits set by FAO/WHO. Heavy metal concentrations in soil were found in the order of Cr>Ni>Pb>Zn>Cd and showed significantly (p < 0.001) higher concentrations as compared to reference soil. The integrated pollution load index (PLI) value was observed greater than three indicating high level of contamination in the study area. The concentrations of Cr (1.80–6.99 mg/kg) and Cd (0.21–0.90 mg/kg) in foodstuffs exceeded their safe limits, while Zn, Pb, and Ni concentrations were observed within their safe limits. In all foodstuffs, the selected heavy metal concentrations were accumulated significantly (p < 0.001) higher as compared to the reference, while some heavy metals were observed higher but not significant like Zn in pear, persimmon, white mulberry, and date-plum; Cd in pear, fig and white mulberry; and Pb in walnut, fig, and pumpkin. The health risk assessment revealed no potential risk for both adults and children for the majority of heavy metals, except Cd, which showed health risk index (HRI) >1 for children and can pose potential health threats for local inhabitants. Graphical Abstract Heavy metals released from chromite mining lead to soil and foodstuff contamination and human health risk
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