Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 15

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
1

Growth and acclimatization response of sunflower plantlets treated with naphthyl acetic acid-based environment friendly plant growth promoters

100%
Sabir A. A., Bareen F., Rehman M. Z., Ahmad S. R.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 3
Preparing novel compounds using environment-friendly protocols for plant growth has remained a major goal for plant scientists. In this research, effect of a novel plant growth promoter on sunflower (Helianthus annuus L.) was assessed hydroponically as well as in soil acclimatized plantlets at 1, 10, and 100 µM. The plants were also assessed for antioxidant enzymatic and antifungal activities. The synthesized derivative 2 produced significantly better results in terms of overall growth as compared with standards at 1 µM concentration among all compounds. Increased catalase and superoxide dismutase levels in plant seedlings treated with synthesized compounds were observed when grown in hydroponics, but these values were found to be significantly low as compared to soil-acclimatized plants. No significant zone of inhibition was found on agar plates in antifungal bioassay
2

Health risk surveillance of arsenic in wastewater, groundwater, and agricultural land along Hudaira Drain, Pakistan using GIS techniques

100%
Javaid A., Ahmad S. R., Qadir A.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 2
The present study focuses on the health risk assessment and spatial distribution of arsenic in Hudaira Drain and its adjoining areas using GIS techniques. For this purpose, surface water, groundwater, and soil samples were collected from the nine transects across the drain. The results of the present study indicated that two of the examined transects were situated in a high arsenic concentration zone and this area was dominated by industrial activities. A strong correlation at 95% confidence level exists among drain water, ground water, and soil. Furthermore, Hazard quotient (HQ) was calculated and results indicated that about 75% of children and 50% of adults may be affected by arsenic through drinking of groundwater. The presence of arsenic in groundwater, which is a major source of drinking water in this area, may cause excess lifetime cancer risk (ELCR)> 10⁻⁴ in 44.4% of the resident human population. There is an urgent need to focus on the arsenic contamination issue in this area in order to protect the groundwater, surface water, and soil resources from arsenic contamination for better human health.
3

Evaluation of surface water quality on spatiotemporal gradient using multivariate statistical techniques: a case study of River Chenab, Pakistan

100%
Kausar F., Qadir A., Ahmad S. R., Baqar M.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 4
The Chenab River is experiencing deteriorating water quality due to ill-planned industrialization, population pressure, extensive agriculture, water diversion and rapid urbanization. Our study was designed to highlight the spatiotemporal variation in the water quality of the Chenab and identify potential pollution sources using multivariate analyses viz cluster analysis, discriminant analysis, principal component analysis and factor analysis. Water samples were collected from nine sampling sites along the Chenab from 2012 to 2014 during dry and wet seasons. Cluster analysis identified three zones, i.e., least stressed zone (LSZ), moderately stressed zone (MSZ) and highly stressed zone (HSZ). The discriminant analysis differentiated seven parameters (COD, Cl, SO4, K, Cu, Cd and Pb) and five parameters (TDS, Cl, S, F and Ca) as most significant on spatial and temporal bases, respectively. The untreated industrial and domestic wastewater, atmospheric deposition and surface runoff containing heavy metals and fertilizer along with a decrease in dilution factor due to the diversion of the water through link canals were identified as the major factors causing water quality deterioration. Therefore, the results imply that a comprehensive water management plan and implementation of environmental laws are urgently needed to protect Chenab water quality.
4

Biogas synthesis from leather industry solid waste in Pakistan

88%
Ijaz M., Tabinda A. B., Ahmad S. R., Khan W. U., Yasin N. A.
Polish Journal of Environmental Studies
|
2020
|
tom 29
|
nr 5
5

Evaluating morphometric parameters of Haro River drainage basin in Northern Pakistan

88%
Sanaullah M., Ahmad I., Arslan M., Ahmad S. R., Zeeshan M.
Polish Journal of Environmental Studies
|
2018
|
tom 27
|
nr 1
We evaluated morphometric parameters of the Haro River drainage network to determine flooding potential in the river basin. The drainage network is derived from topographic maps while using shuttle radar topography mission digital elevation model (SRTM-DEM) and geographic information systems (GIS). A total of 2917 streams (dendritic to semi-dendritic) are recognized, among which 1,536 are identified as first-order streams, followed by 731 as second order, 360 as third order, 173 as fourth order, 78 as fifth order, and 39 as sixth order. Linear and areal morphometric parameters revealed lower values for form factor (0.25), stream frequency (0.99), and drainage density (0.84 km/ sq.km), which suggest that the basin is being elongated with permeable strata; whereas lower values of mean bifurcation ratio (2.0) and relief ratio (20.68) indicate less potential for flooding in the main river channel. Understanding drainage morphometry could bring better hydrological solutions for similar studies.
6

In vitro Response of Bougainvillea explants and their antioxidant enzymatic activities treated with naphthyl acetic acid-based synthetic plant growth promoters

88%
Sabir A. A., e-Bareen F., Zia-ur-Rehman M., Ahmad S. R., Shafig M.
Polish Journal of Environmental Studies
|
2018
|
tom 27
|
nr 4
The synthesis of growth-promoting compounds for better yield of food crops and benefit to mankind has always been a desire of plant scientists, but the use of hazardous solvents in the process and the low yield of such organic compounds have been major challenges. In this research, naphthyl acetic acid-based compounds were prepared using green chemistry protocols, including microwaves and environmentally friendly solvents. The prepared compounds were chemically characterized to be Schiff bases and ethyl esters. The prepared compounds were assessed for the in vitro growth-promoting capability of Bougainvillea glabra explants on MS basal medium. The concentration range of 1, 10, and 100 μM of the compounds was used and the comparison was made with standard thidiazuron (TDZ). The B-10 and B-13 compounds among Schiff bases and B-11 and B-14 compounds among ethyl esters (derived from naphthyl acetic acid moieties) produced significantly better growth response as compared to commercial standard at 1 μM concentration in B.glabra explants. Increased catalase and superoxide dismutase levels in explants treated with synthesized compounds indicated stress alleviation in explants through antioxidant enzyme production.
7

Assessing heavy metal contamination in oil and gas well drilling waste and soil in Pakistan

88%
Qaiser W. S. H., Ahmad I., Ahmad S. R., Afzal M., Qayyum A.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 2
The contamination of soil and water with heavy metals is one of the major environmental problems in the world. Oil and gas exploration and production activities contaminate the environment with heavy metals. In this study, heavy metal concentration was assessed in drilling waste discharges of different oil and gas wells at Khyber Pakhtunkhwa (KP), Pakistan. Moreover, the concentration of heavy metals in the soil surrounding the drilling waste discharges was determined. The representative samples were collected from seven oil and gas drilling waste discharges and the surrounding soil. The collected samples were analyzed for selected heavy metals (Ba, Pb Cr, Cd, Zn, Mn, and Ni) by atomic absorption spectrometric standard methods. Analysis showed that oil and gas well drilling operation waste is enriched with determined heavy metals. The high concentration of heavy metals, particularly Ba and Pb, was also found in the surrounding soil samples. In particular, Ba concentration varied from 1050 to 4168 mg/kg soil. Statistical correlational analysis depicted a common origin of the heavy metals in the soil of the study area, potentially the drilling waste discharges from oil and gas wells. The concentration of heavy metals in oil and gas well drilling waste discharge high, and also affects surrounding soils.
8

Effect of Enterobacter sp. CS2 and EDTA on the phytoremediation of Ni-contaminated soil by Impatiens balsamina

76%
Yasin N. A., Khan W. U., Ahmad S. R., Ali A., Ahmad A., Akram W.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 1
During our current study we evaluated the effect of ethylenediaminetetracetic acid (EDTA) and Enterobacter sp. CS2 on nickel stress alleviation and phytoextraction by Impatiens balsamina L in spiked soil. Nickel resistant Enterobacter sp. CS2 was isolated from soil polluted by industrial effluents. The I. balsamina seeds primed with Enterobacter sp. CS2 were raised in EDTA-supplemented soil (10 mM) contaminated with 0, 100, 200, and 300 mg kg⁻¹ Ni for 50 days. The effect of different treatments on plant growth attributes, nickel tolerance index, bioconcentration factor, and translocation factor were evaluated. The Ni stress reduced plant growth, carotenoids, and chlorophyll (chl) content. However, higher Ni uptake and proline contents were observed in plants growing in Ni-contaminated soils. The Enterobacter sp. CS2 inoculation further enhanced Ni uptake and proline contents in I. balsamina plants growing under Ni stress. The inoculated plants showed improved shoot length, root length, carotenoid content, chl ‘a’ and ‘b’ contents, root and shoot dry weight. The Ni tolerance index in Enterobacter sp. CS2-assisted plants was much higher compared to un-inoculated ones. The inoculated plants supplemented with EDTA enhanced 39%, 34%, and 30% Ni uptake in roots respectively under 100, 200, and 300 mg kg⁻¹ of Ni treatment as compared with un-inoculated plants. The data regarding bioconcentration factor and translocation factor showed that Ni phytoextraction capability of I. balsamina plants was significantly enhanced with the supplementation of Enterobacter sp. CS2 and EDTA.
9

Municipal solid waste as a renewable source of energy: an overview from the Lahore district in Punjab, Pakistan

76%
Shahzad S., Butt A., Anwar S., Ahmad S. R., Sarvar T., Asghar N.
Polish Journal of Environmental Studies
|
2017
|
tom 26
|
nr 6
Pakistan is currently facing a severe energy crisis. According to the latest 2016 figures issued by the government of Pakistan (GOP), electricity demand of the country is about 21,200 MW against the maximum generation 16,000 MW, with a shortfall of about 5,000 MW. The presented study was carried out to find an environmentally friendly renewable source of energy to fill this gap. For this purpose Lahore municipal solid waste was used to calculate the power generation potential. Sampling was completed from all three economic zones – high income (H), medium income (M), and low income (L) – during the whole year, capturing the impacts of all seasons. These samples were brought to a laboratory and analyzed for their calorific values with the help of a bomb calorimeter according to WTE-thermal treatment process. Gross calorific and theoretical energy recovery potential value (from H, L, and M) areas were 3,670, 2,753, and 1,960 kcal/ kg, and 5,872, 4,405, and 3,136 kwh/ton, respectively. This waste-to-energy (WTE) treatment is the most suitable solution for pollution-free LMSW conversion into a renewable energy generation source.
10

Dietary exposure of contaminants through drinking water and associated health risk assessment

76%
Akhtar S., Fatima R., Soomro Z. A., Hussain M., Ahsan M., Ahmad S. R.
Polish Journal of Environmental Studies
|
2018
|
tom 27
|
nr 2
This study investigated physico-chemical drinking water quality of 115 water supply schemes of of District Mianwali along with estimating the health risks associated with the intake of arsenic and flouride in drinking water. One sample was collected from the source end while two samples were collected from consumer ends of each scheme. Overall results showed that 81% of the water samples were safe while 19% were unsafe for drinking purposes. Results showed that TDS (30%), chloride (15%), sulphate (40%), calcium (40%), sodium (14.2%), hardness (24%), nitrate (13%), flouride (30%), and arsenic (7%) exceeded World Health Organization (WHO) standards. Pearson correlation matrix also showed statistically significant relationships (p<0.01) between various physico-chemical parameters and statistically strong significant positive relationships (r = 0.68-1.00, p<0.01) between TDS, Ca, SO₄²⁻, and hardness.There was no variation in the source and consumer end water quality. Risk assessment revealed a low potential health risk to the population of Mianwali for arsenic at source 0.4309<1 (mean) and consumer ends 0.70438<1 (mean), and F- 0.4339<1 at source (mean) and 0.4068<1 (mean) at consumer ends. Hence, this study is in time for the authorities to act immediately, as Mianwali groundwater quality is deteriorating.
11

Role of Acinetobacter sp. CS9 in improving growth and phytoremediation potential of Catharanthus longifolius under cadmium stress

76%
Yasin N. A., Khan W. U., Ahmad S. R., Ahmad A., Akram W., Ijaz M.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 1
Some rhizobacteria are capable of improving metal tolerance and growth of plants under heavy metal stress. The objective of the current study was isolation and subsequent application of cadmium-resistant rhizobacteria in phytoremediation by Catharanthus longifolius. The screened bacterial isolate exhibited growth-promoting attributes, including phosphate solubilization, ACCD activity, auxin, and siderophores production. The inoculation of Acinetobacter sp. CS9 under greenhouse trial improved growth and phytoextraction capability of C. longifolius plants in soils contaminated with different concentrations (0, 100, and 200 mg kg⁻¹) of Cd. The plants exhibited reduced quantity of total soluble protein, soluble sugars, and chlorophyll contents under Cd stress. On the other hand, improved chlorophyll, soluble protein, and sugar contents were observed in Acinetobacter sp. CS9-treated plants. The inoculated plants exhibited improved activity of antioxidant enzymes (SOD and CAT) and reduced malondialdehyde levels. Moreover, higher Cd uptake and translocation ratio was observed in Acinetobacter sp. CS9-inoculated plants as compared to un-inoculated ones. The current study showed that Acinetobacter sp. CS9 reduced Cd-induced oxidative stress and improved the phytoremediation capability of C. longifolius.
12

Dust generation and respiratory impact of underground coal-producing mines in Pakistan

76%
Ijaz M., Akram M., Ahmad S. R., Khan W. U., Thygerson S. M., Nadeem F. A.
Polish Journal of Environmental Studies
|
2020
|
tom 29
|
nr 5
13

Synthesizing and characterizing Sawdust biochar/Fe3O4 nanocomposites and its potential application in textile wastewater treatment

64%
Nadeem F., Jamil N., Moazzam A., Ahmad S. R., Lateef A., Khalid A., Qadir A., Ali A., Munir S.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 4
The present research deals with the synthesis and viability of Sawdust biochar/Fe3O4 nanocomposite toward textile waste water treatment. The structure, functionality, and morphology of the nanocomposite were determined by FT-IR, powder XRD, and SEM. Removal of the textile dye Reactive Blue 21 (RB21) was almost 75% under optimum conditions. The value of Langmuir dimensionless separation factor RL indicated a favorable adsorption (01), hence denoting favorable sorption. The negative values for free energy indicated a spontaneous reaction. Positive value for enthalpy suggested the endothermic nature of adsorption. The kinetic data showed a pseudo first-order kinetic model. The calculated value of qt agreed with the experimental value of qt at equilibrium. The results depicted that sawdust biochar/Fe3O4 nanocomposites are efficient adsorbents for removing RB21 and has potential application in treatment of textile wastewater.
14

Production of cellulases by Bacillus cellulosilyticus using lignocellulosic material

64%
Maryam B., Qadir A., Zameer M., Ahmad S. R., Nelofer R., Jamil N., Arzoo S., Afzaal R.
Polish Journal of Environmental Studies
|
2018
|
tom 27
|
nr 6
The enzyme cellulase, a multi enzyme complex made up of several proteins, catalyses the conversion of cellulose to glucose in an enzymatic hydrolysis. In this study biomass alkali-pretreatment followed by enzymatic hydrolysis was carried out using crude cellulase enzyme produced from screened bacillus strain (Bacillus cellulosilyticus) having 1,998.79 IU/ml/min CMCase and 1,621.16 IU/ml/min FPase enzyme activity. The production of cellulase enzyme using an economical medium has been a significant achievement in the field of industrial biotechnology. The maximum yield of sugars in the form of total sugars (179.84±0.2 mg/ml), reducing sugars (126.72±0.1 mg/ml), and glucose (105.40±0.1 mg/ml) was achieved at 48 h incubation time, 50ºC, 5 pH, 6% enzyme concentration, 4% substrate loading, and PEG 3350 as a surfactant.
15

Hydrological and ichthyological impact assessment of rasul barrage, river Jhelum,Pakistan

64%
Iqbal H. H., Shahid N., Qadir A., Ahmad S. R., Sarwar S., Ashraf M. R., Arshad H. M., Masood N.
Polish Journal of Environmental Studies
|
2017
|
tom 26
|
nr 1
Over the years surface water quality of Pakistani rivers has been degraded. The current study aims to investigate the water quality and fish diversity at Rasul Barrage in the Jhelum River. A total of six sampling sites were assessed for pollution levels and fish fauna of the Barrage. Physicochemical parameters such as turbidity, biological oxygen demand (BOD), and chemical oxygen demand (COD) were deviating from the permissible limits of fresh water set by the U.S. Environmental Protection Agency (EPA), but meeting the criteria of NEQS, whereas pH, temperature, electrical conductivity (EC), total dissolved solids (TDS), total suspended solids (TSS), sodium, and chloride were below the permissible limits of NEQS, but the TSS level was above EPA standards. However, the concentrations of metals such as iron (2.62-3.98 mg L⁻¹), chromium (0.03-0.59 mg L⁻¹), and nickel (0.49⁻¹.71 mg L⁻¹) were higher than the permissible limits for drinking and irrigation waters. In addition, a total of 35 fish species belonging to eight families were identified. Survey and result of study showed that concentrations of pollutants and non-stop fishing activities of commercial fish are the main reasons for the reduction of fish fauna. Two exotic fish species, Oreochromismossambicus and Ctenopharyngodon idella, were found to be abundant where population of native fish fauna numbers were being reduced. We concluded that the surface water quality is poor, as is evident from the higher concentrations of BOD, COD, and metals. Urgent measures are required to prevent such contamination and regular monitoring of water quality in the study area.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.