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Effects of sulfur dioxide on growth, photosynthesis and enzyme activities of Chinese guger-tree seedlings.
1994
Sheu B.H.
Relationship between foliar injury and changes in antioxidant levels in red and Norway spruce exposed to acidic mists.
1991
Chen Y.M. | Lucas P.W. | Wellburn A.R.
Effects of SO(2), NO(2), and O(3) on population development and morphological and physiological parameters of native herb layer species in a beech forest.
1989
Steubing L. | Fangmeier A. | Both R. | Frankenfeld M.
Predisposition of trees by air pollutants to low temperatures and moisture stress.
1995
Chappelka A.H. | Freer Smith P.H.
Heavy-metal ecology of terrestrial plants, microorganisms and invertebrates. A review.
1989
Tyler G. | Balsberg Paahlsson A.M. | Bengtsson G. | Baaaath E. | Tranvik L.
The ecophysiological indicators of air pollution stress of beech (Fagus sylvatica L.) in Zasavje area, Central Slovenia
2002
Kalpic, A.B. (Ecological Research and Industrial Cooperation, Velenje (Slovenia)) | Lasnik, C.R.: Simoncic, P.
Several investigations about air pollution impact on forests have been carried out in Slovenia during last thirty years, mainly using the Norway spruce (Picea abies [L.] Karst.) as the main bioindication species, but there is a lack of information about common beach (Fagus sylvatica L.) condition, the most important forest tree species in Slovenia and in Zasavje area. The assessment of air pollution effect on beech based on stress physiological indicators of foliage, macronutrients level in beech leaves and by assessment of crown defoliation was carried out altogether with necessary soils analyses of the selected beech stands. On the basis of all parameters it can be concluded that the worst condition of beech trees in Zasavje is due to high level of air pollution, mainly by sulphur dioxide and not by deficiency of macronutrients or unfavourable state of soils
Mostrar más [+] Menos [-]Physiological responses of Ailanthus altissima Desf. young plants in an area with high ozone pollution levels
2002
Bussotti, F. (Universita di Firenze, Firenze (Italy). Dipartimento di Biologia Vegetale) | Desotgiu, R. | Grossoni, P. | Gravanio, E. | Rodriguez, R.M.
Ailanthus altissimia Desf. is a non-native species spread throughout the Southern Europe as invasive plant. It demonstrated to be very sensitive to ozone and ozone-polluted environment, develops brownish stipples on the upper leaf surface. In the 2001 summer 12 young plants were placed in a site near the city of Florence (Italy), where high levels of ozone were experienced. Six of them were regularly watered and six were watered only when the wilting of their leaves was evident. Regular assessments were done during the experiment. They concerned growth, production of new leaves, dead and shedding of old leaves, visible symptoms of damage, stomatal conductance and CO2 uptake, chlorophyll fluorescence. The results suggest that the sensitivity to ozone of watered plants is connected to their higher growth ratio and stomatal conductance. Ozone plays a more important role than drought in producing foliar stress conditions
Mostrar más [+] Menos [-]Effect of zinc and iron oxide nanoparticles on plant physiology, seed quality and microbial community structure in a rice-soil-microbial ecosystem
2022
Afzal, Shadma | Singh, Nand K.
In this study, we assessed the impact of zinc oxide (ZnO) and iron oxide (FeO) (<36 nm) nanoparticles (NPs) as well as their sulphate salt (bulk) counterpart (0, 25, 100 mg/kg) on rice growth and seed quality as well as the microbial community in the rhizosphere environment of rice. During the rice growing season 2021–22, all experiments were conducted in a greenhouse (temperature: day 30 °C; night 20 °C; relative humidity: 70%; light period: 16 h/8 h, day/night) in rice field soil. Results showed that low concentrations of FeO and ZnO NPs (25 mg/kg) promoted rice growth (height (29%, 16%), pigment content (2%, 3%)) and grain quality parameters such as grains per spike (8%, 9%), dry weight of grains (12%, 14%) respectively. As compared to the control group, the Zn (2%) and Fe (5%) accumulations at their respective low concentrations of NP treatments showed stimulation. Interestingly, our results showed that at low concentration of both the NPs the soil microbes had more diversity and richness than those in the bulk treated and control soil group. Although a number of phyla were affected by the presence of NPs, the strongest effects were observed for change in the abundance of the three phyla for Proteobacteria, Actinobacteria, and Planctomycetes. The rhizosphere environment was notably enriched with potential streptomycin producers, carbon and nitrogen fixers, and lignin degraders with regard to functional groups of microorganisms. However, microbial communities mainly responsible for chitin degradation, ammonia oxidation, and nitrite reduction were found to be decreased. The results from this study highlight significant changes in several plant-based endpoints, as well as the rhizosphere soil microorganisms. It further adds information to our understanding of the nanoscale-specific impacts of important micronutrient oxides on both rice and its associated soil microbiome.
Mostrar más [+] Menos [-]Plant senescence: A mechanism for nutrient release in temperate agricultural wetlands
2007
Kröger, R. | Holland, M.M. | Moore, M.T. | Cooper, C.M.
The beneficial uptake of nutrients by wetland plants is countered to some extent by nutrient release back into the aquatic environment due to vegetative die-back. This current study examined whether Leersia oryzoides, a common wetland plant, exhibits luxury uptake of nutrients from simulated farm runoff. The study also tested whether with subsequent decomposition, these nutrients are released back into the water column. When exposed to elevated (>2 mg/L N and P) runoff, L. oryzoides assimilated significantly higher concentrations of nitrogen (p < 0.001) and phosphorus (p < 0.001) in above-ground biomass as compared to non-enriched treatments (<0.05 mg/L N and P). Subsequently, senescence of enriched above-ground biomass yielded significantly higher concentrations of phosphorus (2.19 ± 0.84 mg P/L). Using L. oryzoides as our model, this study demonstrates nitrogen and phosphorus sequestration during the growing season and release of phosphorus in the winter. Release of sequestered nutrients during plant senescence.
Mostrar más [+] Menos [-]Aspergillus niger-mediated release of phosphates from fish bone char reduces Pb phytoavailability in Pb-acid batteries polluted soil, and accumulation in fenugreek
2022
Tauqeer, Hafiz Muhammad | Basharat, Zeeshan | Adnan Ramzani, Pia Muhammad | Farhad, Muniba | Lewińska, Karolina | Turan, Veysel | Karczewska, Anna | Khan, Shahbaz Ali | Faran, Gull-e | Iqbal, Muhammad
Soil receiving discharges from Pb-acid batteries dismantling and restoring units (PBS) can have a high concentration of phytoavailable Pb. Reducing Pb phytoavailability in PBS can decline Pb uptake in food crops and minimize the risks to humans and the environment. This pot study aimed to reduce the concentration of phytoavailable Pb in PBS through Aspergillus niger (A. niger)−mediated release of PO₄³⁻ from fish bone [Apatite II (APII)] products. The PBS (Pb = 639 mg kg⁻¹ soil) was amended with APII powder (APII−P), APII char (APII−C), and A. niger inoculum as separate doses, and combining A. niger with APII−P (APII−P + A. niger) and APII−C (APII−C + A. niger). The effects of these treatments on reducing the phytoavailability of Pb in PBS and its uptake in fenugreek were examined. Additionally, enzymatic activities and microbial biomass carbon (MBC) in the PBS and the indices of plant physiology, nutrition, and antioxidant defense machinery were scoped. Results revealed that the APII−C + A. niger treatment was the most efficient one. Compared to the control, it significantly reduced the Pb phytoavailability (DTPA-extractable Pb fraction) in soil and its uptake in plant shoots, roots, and grain, up to 61%, 83%, 74%, and 92%. The grain produced under APII−C + A. niger were safe for human consumption as Pb concentration in grain was 4.01 mg kg⁻¹ DW, remaining within the permissible limit set by WHO/FAO (2007). The APII−C + A. niger treatment also improved soil pH, EC, CEC, MBC, available P content and enzymatic activities, and the fenugreek quality parameters. A. niger played a significant role in solubilizing PO₄³⁻ from APII−C, which reacted with Pb and formed insoluble Pb-phosphates, thereby reducing Pb phytoavailability in PBS and its uptake in plants. This study suggests APII−C + A. niger can remediate Pb-polluted soils via reducing Pb phytoavailability in them.
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