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Purification Efficiency of Eutrophic Water by Three Submerged Plants Full text
2023
Y. Hu, D. X. Qian, H. Zhu, L. F. Wang, B. Wang, Q. F. Ling and X. D. Xiao
The increase of nitrogen and phosphorus causes eutrophication in water bodies. Using submerged plants to decrease the pollution from water bodies is an effective way. In this research, three common submerged plants (Vallisneria natans, Hydrilla verticillata, and Ceratophyllum demersum) and their combinations were used to purify eutrophic water. The control treatment did not contain any plants. The removal effects and dynamic regulations of the three plants with their combinations of nutrients (such as nitrogen and phosphorus) in water were analyzed. All three species and their combinations above could grow in the eutrophic water and efficiently remove aquatic nutrients. All the treatment groups had a higher pollutant removal rate for total nitrogen (TN) and total phosphorus (TP) than that of the blank control. In these treatment groups, treatment F (50 g Vallisneria natans plus 50 g Ceratophyllum demersum) had the highest removal rate of TP at 57.53%; treatment B (100 g Vallisneria natans) had the best removal rate of TN at 92.04 %. Among these plants and their combinations, Vallisneria natans and Ceratophyllum demersum showed better purification ability; the combination of these two submerged plants and the combination of three submerged plants were more applicable for the restoration of eutrophic water.
Show more [+] Less [-]Assessment of Sodium Chloride (NaCl) Induced Salinity on the Growth and Yield Parameters of Cichorium intybus L. Full text
2023
A. Khan, A. A. Khan, S. Samreen and M. Irfan
The present study was done on the hypothesis that excess sodium chloride (NaCl) in the soil decreases the growth and yield of Cichorium intybus L. To investigate this hypothesis, a pot experiment was conducted in which chicory seeds were sown in garden soil-filled earthen pots and treated with three different doses of sodium chloride (45, 75, and 105 mM kg-1 soil) except the control, and each treatment was replicated three times. The results revealed that all the saline treatments significantly (p≤0.05) reduced the vegetative (including root and shoot length, dry weight, number of leaves, leaf area, number of branches, and photosynthetic pigments) and reproductive (mean fruit number/plant, mean seed number/fruit, and total seed yield/plant) growth parameters of Cichorium intybus. On increasing NaCl concentration in the soil, chlorophyll content significantly (p≤0.05) decreased while proline content in the fresh leaves increased significantly (p≤0.05). From the results, it is concluded that Cichorium intybus L. can tolerate a moderate level of sodium chloride stress (45-75 mM NaCl kg-1 soil) but is sensitive to high doses of sodium chloride stress (105 mM NaCl kg-1 soil).
Show more [+] Less [-]Heavy Metal Pollution of Soil and Crops in Rural Gujarat, Next to an Industrial Area: A Correlation Study Full text
2023
A. Salauddin and C. Sandesh
Heavy metal contamination is one of the significant concerns of environmental pollution. The present study was conducted to find out the correlation between soil and crop/food matrices grown at the exact location for Al, As, Ca, Cd, Cr, Cu, Fe, Hg, K, Mg, Mn, Ni, Na, P, Zn, and Pb elements near the industrial areas of Narol, Changodar, Vatva, Makarpura, Nandesari, and Ankleshwar in Gujarat, India. Soil samples were collected from 64 sampling sites in an industrial area. Twenty of these sites contained crop/food matrices used for the correlation study. The ranges of concentration of Cr (17-74.4 mg.kg-1), Cu (9.6-82.4 mg.kg-1), Ni (10.6-55.9 mg.kg-1), Pb (4.5- 20.7 mg.kg-1), Zn (21.5-112.4 mg.kg-1), and Al (7075-44557.5 mg.kg-1) for Soil and for crop Cr (0.3-0.6 mg.kg-1), Cu (0.3-8.6 mg.kg-1), Zn (1.1-43.5 mg.kg-1), Fe (12.6-69.4 mg.kg-1), and Al (5.8-102.2 mg.kg-1). According to the study, there is a strong correlation between the soil and crop/food matrices at the different locations, like 0.97 for Fe and Ni, 0.94 for Mg, 0.95 for Mn, and 0.55 for Pb and Zn, and very little correlation between K, P, and Ca, while a negative correlation between Al, Cr, Cu, and Na. The DTPA extractable method was used for the elemental analysis, and analysis was done using the ICP-OES instrument following microwave-assisted digestion. The results show that metal contamination transforms from soil to crop/food matrices, which represents a serious concern and requires action to address the metal contamination by industrialization.
Show more [+] Less [-]Moringa Oleifera Coagulation Characteristics in Wastewater Treatment in a University Dormitory Full text
2023
M. S. Ogunshina, O. M. Abioye, K. A. Adeniran and D. A. Olasehinde
Wastewater treatment necessitates the use of an appropriate method to achieve satisfactory results. The conventional method of Alum addition has been widely used for years, but it is prohibitively expensive. This study uses Moringa oleifera, an inexpensive and readily available plant, as a natural coagulant to treat wastewater collected from university dormitories. Physicochemical parameters such as pH, Turbidity, Electrical Conductivity (EC), Total Dissolved Solids (TDS), Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), and Dissolved Oxygen (DO) were examined based on appropriate standards. Wastewater treatment with varied coagulant dosages of 50, 100, and 150 mg.L-1) was monitored using a standard jar test device with an initial wastewater perturbation at 100 rpm for 5 min was reduced to 50 rpm in 10 minutes with a rest time of 30 min. The results showed that the quality of the physicochemical properties of the water improved. The percentage increase in the water quality is; BOD (92%), COD (92%), and TDS (52-64%), with an increase in Moringa coagulant achieving a reduction of 96% of Turbidity. While the DO improved (79%), the pH remained below acceptable limits (6.73-7.56) for effluent disposal. The treated water showed clarity (colorless) and no odor compared to the wastewater. Hence, Moringa oleifera seeds cake residue can be an effective coagulant for wastewater treatment.
Show more [+] Less [-]Topographic Gradient Differentiation and Ecological Function Zoning Based on Ecosystem Services: A Case Study of Fuping County Full text
2023
Ling He, Zhe Du, Jiabo Tian and Shuqi Chen
Scientifically delineating ecological function zones is essential for national territory spatial planning and comprehensive management. In this study, we evaluated five ecosystem services, habitat quality, water yield, carbon sequestration, soil conservation, and food production, in Fuping County, China, and introduced the application of the topographic position index in exploring the topographic gradient effect of each service. We next applied the K-means clustering algorithm to identify the ecosystem services bundles and analyze the dominant type of ecosystem service in these bundles. A particle swarm optimization-support vector machine model was also constructed to identify the boundaries of ecological function zones and complete the ecological function zoning. The results are as follows: (1) In Fuping County, the high-value areas of habitat quality are distributed in the west, north, and southeast; those of soil conservation are in the northwest, northeast, and southwest; those of water yield are in the east and south; those of carbon sequestration are in the west, and those of food production is in the east. (2) The habitat quality first decreases and then increases with an increasing topographic gradient; food production and water yield decline with increasing topographic gradient; carbon sequestration and soil conservation increase with increasing topographic gradient. (3) Four types of ecosystem services bundles were identified. The dominant ecosystem functions of Type I, II, and III bundles are food production and water yield, carbon sequestration, and soil conservation, respectively. Type IV bundles generally have low levels of ecosystem services in the study area. (4) Four ecological function zones were delineated: food production zone, ecological conservation zone, potential restoration zone, and critical restoration zone. The research findings can provide a theoretical and practical basis for formulating and implementing ecological spatial management policies in the Taihang Mountains of China.
Show more [+] Less [-]An Inappropriate Rise in NO2 During the COVID-19 Pandemic in the Urban Area of Chhattisgarh, India Full text
2023
A. Zeb, I. U. Khan, S. Tripathi, M. R. Sahu and A. Kumar
The COVID-19 first case was reported in India on January 30, 2020, and in Chhattisgarh on March 19, 2020, and since then a sharp surge has been noticed. The government of India imposed a nationwide lockdown on March 25, 2020, a complete suspension of human activities, viz., industry, construction, transport, academic institutions, etc., which resulted in an improvement in air quality (a decrease in PM2.5 and PM10, alteration in NO2 and an increase in O3). But the rate of cases of COVID-19 has increased sharply, and eventually, under economic pressure, the lockdown was withdrawn on June 1, 2020, which further accelerated the exponential growth of COVID-19 cases. We noticed that in the Chhattisgarh State of India, the alteration in the air quality index during the lockdown period is continuing even after the restoration of anthropogenic activities. Among PM2.5, PM10, NO2, and O3, the behavior of NO2 was found to be different than others; it was found to increase during the lockdown period but further decreased with the resumption of anthropogenic activities. We conclude that the air quality index has an insignificant impact on COVID-19 infection.
Show more [+] Less [-]Review of Outdoor Air Pollution in Sri Lanka Compared to the South Asian Region Full text
2023
L.R.S.D. Rathnayake, G.B. Sakura and N.A. Weerasekara
Air pollution is a significant issue that affects almost all the countries in the world while predominating in South Asian Regional countries due to poverty, less attention, and less awareness towards the implementation and obeying of air quality guidelines in public. As a developing country, Sri Lanka stands at an optimum state of national air quality compared to other SARC because it is an island with a minor population compared to India, Pakistan, Bangladesh, etc. Maldives and Bhutan lie straightforwardly in owing mild air quality in SARC. However, SARC is far behind the world in maintaining optimistic air quality nationwide. Ambient air pollution-attributable deaths have become interim in past decades, a severe burden to the sustainable existence of SARC. A well-established systematic epidemiological, empirical studies and revisions regarding air pollution, strategic planning for mitigating air pollution, and frequent Spatio-temporal pollution monitoring nodes are necessary for Sri Lanka to achieve the sustainable goal. Other South Asian countries: India, Bangladesh, Pakistan, Afghanistan, Nepal, Bhutan, and Maldives, also should pay attention to minimizing outdoor air pollution nationwide for the betterment of future existence.
Show more [+] Less [-]Concentration of Toxic Heavy Metals and Phytochemicals in a Medicinal Plant (Asclepias fruticosa) Collected Around Mining Areas in Brits, Pretoria Full text
2023
L. L. Mugivhisa, D. Mzimba and J. O. Olowoyo
The use of African traditional medicine in rural and peri-urban areas is common due to its affordability and accessibility. The study aimed to determine the levels of toxic heavy metals in the medicinal plant (Asclepias fruticosa) samples collected around three mining areas in Brits using ICP-OES. The phytochemical screening analysis was done to indicate the absence or presence of different phytochemicals in the medicinal plant. The results of the qualitative phytochemical analysis indicated the presence of flavonoids, alkaloids, proteins, and carbohydrates in Asclepias fruticosa collected from all the mining areas. The results of the heavy metals showed that the mean highest concentration for all the heavy metals was recorded for Mn from the leaves of the medicinal plants. The trend in the heavy metals accumulation was roots > leaves > stems from all the sites, and the differences were significant (p < 0.05). The range of heavy metals in the plant was in the range Mn (12.33 ± 2.31-85.33 ± 51.07 μg.g-1), Zn (10.67 ± 0.58-60.33 ± 0.56 μg.g-1), Cr (3.43 ± 0.06 -34.90 ± 0.10 μg.g-1), Cu (8.67 ± 0.12-18.8 ± 1.57 μg.g-1), Ni (5.67 ± 0.12-23.23 ± 1.7 μg.g-1) and Pb (0.53 ± 0.013-1.59 ± 0.15 μg.g-1). The values of the heavy metals Cr, Zn, and Ni in the plant exceeded the recommended limits set by WHO for human consumption. Heavy metals in the medicinal plant were accumulated in the roots and not translocated to the stems and leaves. It is therefore recommended that communities staying around the mines should be discouraged from picking and using medicinal plants growing around the mines and should be educated on the safety of medicinal plants growing around the mines.
Show more [+] Less [-]Feasibility of Waste-to-Energy Plants for STT-PLN Campus Canteen Full text
2023
Pawenary, Amelia Dwita Larasati, Suhdi and Rulyanti Susi Wardhani
The pellets of waste produced by Society Electric [Listrik Kerakyatan (LK) 2] at the STT-PLN have not been efficiently utilized in terms of energy. The STT-PLN canteen consists of 14 stalls with an installed electricity capacity of 1300 VA, each with 12h of use/day. This study aimed to convert LK 2 waste pellets into electrical energy to supply electricity to the STT-PLN canteen. This research method uses quantitative methods, i.e., by calculating the amount of energy produced adjusted to the needs of the canteen. Gasification technology was chosen due to its high efficiency and lower emission impacts in the waste combustion technique. Based on the analysis, the gasifier engine that complies with this requirement was TG30-1 with a maximum capacity of 25 kVA and requires a flow rate of 10 kg.h-1 of waste pellets. The amount of waste pellets used for this plan was 120 kg.day-1. The assessment results of this plan indicated a net present value of IDR 302,218,609.33, an internal rate of return of 25.7983%, and a PBP of 5.66 years. Based on the economic analysis, the establishment of plants for the conversion of waste to power was declared feasible to operate.
Show more [+] Less [-]Study on Effectiveness of Intervention of a Vertical Flow Constructed Wetland in between Septic Tank and Soak Pit for the Treatment of Septic Tank Effluent Full text
2023
S. Suresh, P. Sharma, R. R. Yaragal and S. Mutnuri
Septage comprises the solid and liquid constituents of any primary treatment system, including a Septic Tank. In this study, the wastewater collected from a septic tank is passed through a partially converted anaerobic filter, and a vertical flow constructed wetland (VFCW) before being sent to a soak pit. The main objective of this case study was to check the effectiveness of incorporating a VFCW between a septic tank and a soak pit to bring down the consequences created due to effluent seepage from soak pits to the groundwater. Conventionally, the effluent gets directly passed to soak pits after primary onsite treatment in the septic tank. The soak pit walls made of porous materials allow the gradual seepage of final effluent into the ground, polluting the groundwater reserves. We analyzed the septic tank effluent from 60 households wherein the effluent was let off into the soak pits. The various parameters analyzed with their averages were 393.83 ± 293.41 mg.L-1 for COD, 151.48 ± 94.37 mg.L-1 for BOD, 30.81 ± 13.05 mg.L-1 for NO3-, 23.35 ± 13.54 mg.L-1 for PO43-, 7.35 ± 0.31 for pH, 184.05 ± 163.20 mg.L-1 for TSS, 3.05 x 107± 2.04 x 108 CFU.100mL-1 for TC. Therefore, it is certain that the final effluent being sent into soak pits after primary treatment does not meet the Central Pollution Control Board (CPCB) discharge standards. In this case study, we were able to obtain final effluent values after VFCW treatment as 55.72 mg.L-1 for COD, 12.12 mg.L-1 for BOD, 10.2 mg.L-1 for NO3-, 3.74 mg.L-1 for PO43-, 7.41 for pH, 8.37 mg.L-1 for TSS, 379.27 mg.L-1 for TS and 51.9 CFU.100mL-1 for TC. With this case study, we were able to resolve this impediment by bringing down the values of all the parameters considered while analyzing under the limits of discharge standards set by CPCB. The removal efficiency of COD, BOD, NO3-, PO43-, pH, TSS, and TC after wetland was found to be 89.46%, 88.051, 63.484, 44.37%, 3.41%, 98.47%, 97.71%, 97.19% respectively. The study has proven that with the introduction of another decentralized treatment system between a septic tank and soak pit, it is safe to dispose of the effluent into soak pits, thereby reducing the chances of groundwater pollution considerably.
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