Assessment of Heavy Metals Contamination in Ground Water around Industrial Region in Nadar Ganj Lucknow

Nadar Ganj being a prominent industrial area of Lucknow Uttar Pradesh, owes its significance to diverse group of industries. this study is to investigate the pollution of bore water in the industrial region in Nadar Ganj industrial area in Lucknow. The contamination of groundwater is one of the most important environmental issues in the world. Among the various pollutants that affect water resources, pollutants containing heavy metals are particularly important due to their high toxicity, even at low concentrations. The percolation water picks up a large number of heavy metals and reaches the aquifer system and contaminates ground water. five ground water sample were collected from the study area in February 2021.the heavy metals (Pb, Fe, Cu, Cr, Ni).

Impact of Sewage Sludge Leaching on Soil Constituents and Quality

Activated sludge treatment plants generate large quantities of sludge each year, thereby posing a serious environmental problem. This study aims to experimentally assess the effect of rainwater on the leaching of sludge components. In this context, a percolation test was set up, and composed of PVC cylinders into which the solid substrate was introduced. Five modalities of the solid substrate were used: a sludge modality, a soil modality and three modalities with increasing percentage of sludge (1%, 5% and 25%) in the soil. The percolation water is collected during the rainy months in bottles placed below each column. Solid substrate samples were taken before the test and after one year. The physicochemical analysis of the percolation water showed an increase in the electrical conductivity, BOD5, COD, nitrogen compounds and phosphate compounds which were proportional to the percentage of sludge. The pH of the sewage sludge leachates varies from 7.61 to 7.98. Zinc and copper were the most mobilized metals. A year following the installation of the percolation test, electrical conductivity, total phosphorus (TP) and orthophosphate (PO4) contents decreased for the solid substrates using the five modalities. Furthermore, ammonium (NH4) and nitrates (NO3) levels decreased in soil mixed with 1 to 25% of sludge due to their leaching by rainwater. Collectively, these data show that the leachates through the soil mixed with sludge are stable and loaded with NO3, a plant nutrient that can contaminate the groundwater as well as the surface waters inducing their eutrophication. Furthermore, addition of sludge to the soil improves the levels of carbon, total nitrogen, TP and PO4 in the soil and thereby soil fertility. The addition of sludge, however, is not without soil contamination with heavy metals. Such soil contamination would cause pollution of surface and ground water. Reaching certain severity, it should call for the adoption of prompt measures for the protection of environment and human health.

Experimental Study on the Evolution of River Water Quality and Riverbank Percolation Water Quality under Reclaimed Water Replenishment

<p>Due to the intensified influence of human activities, Yongding river presents a sharp decrease in water quantity and a trend of continuous deterioration of water environment, and the ecological environment is seriously damaged. Under this background, Yongding river ecological reconstruction project needs to be carried out urgently, and ecological water replenishment mode needs to be determined urgently. In order to explore the influence of multi-water source ecological replenishment mode on the evolution of river water quality and riverbank percolation water quality, this study conducted a simulation experiment to explore the influence of flow rate, temperature and soil percolation on reclaimed water replenishment water quality. The results show that the increase of flow velocity is beneficial to the degradation of pollutants. Compared with high temperature, the degradation capacity of pollutants at low temperature is significantly better than that at high temperature, indicating that low temperature is beneficial to the improvement of reclaimed water quality to some extent. Some water quality indexes of riverbank leachate improved to some extent, but the water passing through the soil was slightly eutrophication due to the aggregation and adsorption of river bottom sediments. The final results show that the velocity of flow has the greatest influence on the quality index of regenerated water.</p>

Fluorescence Characteristics of Dissolved Organic Matter (DOM) in Percolation Water and Lateral Seepage Affected by Soil Solution (S-S) in a Lysimeter Test

: The composition and structure of dissolved organic matter (DOM) are sensitive indicators that guide the water infiltration process in soil. The DOM chemical composition in seepage affects river water quality and changes soil organic matter (SOM). In this lysimeter test study, fluorescence spectra and optical indices were used to examine the interaction between the percolation water (P-W) and leachate water (L-W) DOMs affected by the soil solution (S-S). The L-W DOM had a higher aromaticity (SUVA254), average molecular weight (S275-295) and terrestrial source (fluorescence index (FI)), but fewer autochthonous sources (biological index (BIX)) than the P-W DOM. Organic carbon standardization (OCS) and protein- (PLF), fulvic- (FLF) and humic-like fluorescence (HLF) intensity showed that L-W DOM increased 44%, 55% and 81%, respectively, compared to the P-W DOM. The linear regression slopes between OCS FLF and PLF were 0.62, 1.74 and 1.79 for P-W, L-W and S-S, respectively. The slopes between OCS HLF and PLF were 0.15, 0.58 and 0.64 for P-W, L-W and S-S, respectively. The P-W DOM was in contact with the soil litter layer, where S-S labile lignin phenolic compounds released and dissolved into the L-W DOM. This increased its aromaticity, and extent of humification.

Response of Vertical Migration and Leaching of Nitrogen in Percolation Water of Paddy Fields under Water-Saving Irrigation and Straw Return Conditions

The use of water-saving irrigation techniques has been encouraged in rice fields in response to irrigation water scarcity. Straw return is an important means of straw reuse. However, the environmental impact of this technology, e.g., nitrogen leaching loss, must be further explored. A two-year (2017–2018) experiment was conducted to investigate the vertical migration and leaching of nitrogen in paddy fields under water-saving and straw return conditions. Treatments included traditional flood irrigation (FI) and two water-saving irrigation regimes: rain-catching and controlled irrigation (RC-CI) and drought planting with straw mulching (DP-SM). RC-CI and DP-SM both significantly decreased the irrigation input compared with FI. RC-CI increased the rice yield by 8.23%~12.26%, while DP-SM decreased it by 8.98%~15.24% compared with FI. NH4+-N was the main form of the nitrogen leaching loss in percolation water, occupying 49.06%~50.97% of TN leaching losses. The NH4+-N and TN concentration showed a decreasing trend from top to bottom in soil water of 0~54 cm depth, while the concentration of NO3−-N presented the opposite behavior. The TN and NH4+-N concentrations in percolation water of RC-CI during most of the rice growth stage were the highest among treatments in both years, and DP-SM showed a trend of decreasing TN and NH4+-N concentrations. The NO3−-N concentrations in percolation water showed a regular pattern of DP-SM > RC-CI > FI during most of the rice growth stage. RC-CI and DP-SM remarkably reduced the amount of N leaching losses compared to FI as a result of the significant decrease of percolation water volumes. The tillering and jointing-booting stages were the two critical periods of N leaching (accounted for 74.85%~86.26% of N leaching losses). Great promotion potential of RC-CI and DP-SM exists in the lower reaches of the Yangtze River, China, and DP-SM needs to be further optimized.

Ecosystem Function

An important aspect of all aquatic subterranean ecosystems is the nature and connectivity of surface inputs. A theme common to both is heterogeneity of inputs that exist at even the smallest scale. At least in cave streams, carbon appears to be limiting. Studies at the scale of entire caves are of two very different kinds. For caves with surface inputs, inputs from percolation water are quantitatively less important than inputs from sinking streams, but are qualitatively more important because they occur throughout the cave and form the basis for the biofilm. Sulfur-oxidizing bacteria are the trophic base for most chemoautotrophic cave communities. Only two ecosystem studies of an entire karst basin have been carried out. For the Dorvan basin in France, most carbon entering the ecosystem is DOC, and there is considerable storage of organic carbon in sediments. In the Edwards Aquifer of Texas, chemolithoautotrophy contributes to all the components.

Leaching of heavy metals and barium from forest roads reinforced with fly ash

The aim of this study was to determine the effect of leaching of heavy metals (Cr, As, Cd, Cu, Ni, Pb, Zn, Co, Mo) and earth-alkaline metal, barium (Ba), on the percolation and ditch water quality from the forest roads that contained ash in the road structures. Water quality was studied in the immediate vicinity below the ash layers as well as deeper in the road structure. Water quality was also determined in the drainage water in ditches that crossed the forest roads. A mixture of wood and peat based fly ash was used in the road structures. The treatments were: 1) no ash, 2) a 15 cm layer of ash/gravel mixture, 3) a 20 cm layer of ash/gravel mixture, 4) a 25 cm layer of ash, and 5) a 50 cm layer of ash. Large variation in the concentrations of Cr, As, Cu, Ni, Pb, Mo and Ba in the percolation water, even within the same treatment, caused difficulties to generalize the results. The concentrations of Cr, As, Ni, Pb, Mo and Ba in water samples were high in some treatment plot lysimeters containing ash compared to the control (no ash). On the other hand, many lysimeters had low and similar concentrations in water samples in the treatment plots containing ash compared to concentrations in the control plots. The ash in the roads did not affect the concentrations in the ditches. The leaching is uneven and seems to take place only from some parts of the ash layer. Risk for leaching is minimal if such parts are not widely spread.

Impact and implications of meltwater percolation on trace element records observed in a high-Alpine ice core

ABSTRACTPast atmospheric pollution can be reconstructed from ice core trace element records retrieved from mountain glaciers. However, the current global temperature increase can result in post-depositional melt processes, significantly altering the originally stored information. Here, we present a comprehensive study on the behaviour of 35 trace elements (TEs) during meltwater percolation in a high-Alpine ice core segment from upper Grenzgletscher, Switzerland. Some TEs revealed significant concentration depletion, whereas others were well preserved depending on their water solubility and location at the grain scale. TEs present in insoluble minerals, typically enriched at grain boundaries, were found to be mostly preserved because their insolubility in water results in immobility with meltwater percolation. Water-soluble TEs revealed a variable meltwater-mobility. Whereas ultra-TEs tend to be preserved, likely due to incorporation into the ice lattice, abundant TEs are prone to relocation from grain-boundary regions. We propose that at Alpine sites, Ag, Al, Bi, Cu, Cs, Fe, Li, Mo, Pb, Rb, Sb, Th, Tl, U, V, W, Zr and the rare-earth elements may still be applicable as robust environmental proxies even if partial melting occurred, whereas Ba, Ca, Cd Co, Mg, Mn, Na, Ni, Sr and Zn are prone to significant depletion.