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Chemical characterization of PM2.5 from region highly impacted by hailstorms in South America
2022
Beal, Alexandra | Martins, Jorge A. | Rudke, Anderson P. | de Almeida, Daniela S. | da Silva, Iara | Sobrinho, Otavio Medeiros | de Fátima Andrade, Maria | Tarley, César R.T. | Martins, Leila D.
The chemical composition of particulate material plays an important role in the atmosphere, providing cloud and ice nuclei for storm development. This study aims to evaluate and infer the sources of ions, metals, and metalloids in the fine atmospheric particulate matter (PM₂.₅) from triple border Paraná, Santa Catarina (Brazil), and northeastern Argentina, which is among those with the highest hail incidence in the world. Among the ions, the concentrations presented the following sequence in decreasing order: [Formula: see text]> K⁺> [Formula: see text]> [Formula: see text]> Ca²⁺> Cl⁻> Na⁺> Mg²⁺. Regarding the metals and metalloid concentrations, the order was of S > Si > Al > Fe > P > Ti, Cr, Cu, and Zn > Br > Mn, and Ni. The main sources, supported by positive matrix factorization results, are soil and agricultural activities, as well as vehicular emissions due to the agricultural machinery and the displacement of residents. Besides, the influence of aerosols from biomass burning and industrial activities was observed, possibly come from long-distance transport. The composition of PM₂.₅ presents one or more elements considered present ice nuclei (IN) activity, such as Al, Mn, Cu, Co, Ni, and V (in form of oxides), corroborating with other studies, also, with high hail incidence. However, further studies are needed to verify the role of aerosol characteristics in the formation of IN and, consequently, hail.
Show more [+] Less [-]Environmental risks among rice farmers and factors influencing their risk perceptions and attitudes in Punjab, Pakistan
2020
Ahmad, Dilshad | Afzal, Muhammad | Rauf, Abdur
Farming community confronted with sundry type of risks while production and environmental risks are more significant. Farms management decisions and operations are considerably influenced by farmers’ perceptions and attitude to risks. Risk management issues specific to cereals crops not properly focused in developing countries specifically to Pakistan, so this gap tried to address in this study. This research work was spotlighted to quantify farmers’ perception and attitude of diverse form of risks toward rice crop in Pakistan. The present study used cross-sectional data of 450 rice farmers categorized as low, medium, and high production base six rice districts of Punjab, Pakistan. In attempting to identify farmers attitude to risk, the study used Equally Likely Certainty Equivalent approach, as farmers’ perception were ranked in four catastrophic risk basis, rice diseases, high input prices, drought, and heavy rainfall and hail, by risk matrix. In estimating the factors influencing farmers’ attitude and perceptions to risk, the study used Probit model. Farmers believe heavy rainfall and hails, high input prices, drought, and rice disease major threats for rice crop while mostly farmer is risk-averse behavior as indicated in the results of the study. Estimates of the study signified as education, gender, size of farm, religious, age, credit, off-farm income, farmer livestock, and experience of farming significantly influences farmer risk perception and risk attitude. This research provided applied and suitable investigation for farming community, extension services, researchers, agricultural policymakers, and insurance institutions. Farmers confronting risk and their attitude need to understand by researcher and policymakers’ access them accurate information regarding sophisticated tools of risk management and risks to make sure the provision of advance extension services and agricultural finance. In formulating applied policy measures, it is prerequisite for researchers and policymakers to accurate understanding of local environmental conditions, crop-related threats, and farmers’ perceptions and attitude.
Show more [+] Less [-]Occurrence of ectoparasitic arthropods associated with rodents in Hail region northern Saudi Arabia
2014
Asiry, Khalid A. | Fetoh, Badr El-Sabah A.
Ectoparasitic arthropods are a diverse element of the Saudi fauna. Due to this, a survey of ectoparasites associated with rodents was conducted as a preliminary study in five districts of Hail region of northern Saudi Arabia for the first time. Ectoparasites extracted from 750 rodents were sampled and identified by recording their frequency of appearance. Results revealed that 1,287 ectoparasites infested 316 of the captured rodent hosts. These ectoparasites parasitized on four species of rodents including three species of rats Rattus rattus rattus, Rattus rattus frugivorus, and Rattus rattus alexandrinus and one species of mouse Acomys dimidiatus (Rodentia: Muridae). The ectoparasites belong to four different groups: ticks, fleas, lice, and mites. Ticks were the highest in the number, while fleas were the lowest among all the extracted ectoparasite groups. The collected ectoparasitic arthropods consisted of seven species. Ticks were of two species: Rhipicephalus turanicus and Rhipicephalus sanguineus (Acari: Ixodidae), fleas were of two species: Xenopsylla cheopis and Xenopsyllus conformis mycerini (Siphonaptera: Pulicidae), lice was a single species: Polyplax serrata (Anoplura: Hoplopleuridae), and mites were of two species: Laelaps nuttali and Laelaps echidninus (Mesostigmata: Laelapidae). The findings of the study showed that the intensity of infestation was varied between rodent host sexes, wherein females had the highest rate of parasitic infestation, and the parasitic index of appearance was very high for one group of parasites (i.e., ticks). The parasitic prevalence was 42.13 % on rodents, and mites were the most prevalent parasite species. Overall, this study was carried out to establish baseline data for ectoparasite-infested rodents in Hail region, Saudi Arabia, and may help for appropriate planning to control zoonotic diseases in this area.
Show more [+] Less [-]Wet deposition of the seeding agent after weather modification activities
2013
Ćurić, Mladjen | Janc, Dejan
Weather modification activities are performed mostly by cloud seeding. Some operational projects have been conducted for more than a half century and cover planetary scales. These activities have led to large amounts of seeding agents being deposited on the ground in precipitation. The main intent of this paper is to identify the spatial pattern of silver iodide deposits after hail suppression. The spatial pattern of silver iodide deposits is determined using the weather modification project measurements from seeding agent reports, two weather radars and 316 launching sites during a 5-year period. The estimated spatial distribution of the deposits is not uniform, with the maximum silver iodide amount located in the southern part of the study area (up to 140 μg m(-2)). Our results are comparable with the measurements performed by chemical analyses during other cloud seeding experiments. The maximum location coincides well with that of the maximum seeded hailstorm precipitation frequency. A new method for identifying the spatial pattern of wet-deposited material has been established. The location with the maximum amount is found. This method would be important as a means of placing samplers and monitoring at the representative sites because those are where most weather modification projects would be performed in the future.
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