Urban soil quality of Raipur,Chhattisgarh, India

Soil quality in urban areas in India is degraded due to multiple anthropogenic activities. The objectives of this work are to determine the concentration variations, toxicity, and sources of carbons, metals, and ions in the surface soil of Raipur, the industrialized capital city of Chhattisgarh state, India. High concentrations of Al, K, Ca, Ti, Fe, and elemental carbon (EC) were registered. Relatively lower concentrations of V, Cr, Mn, Ni, Cu, Zn, Sr, Ba, Pb, organic carbon (OC), and carbonate carbon (CC), as well as ions (viz. F^–, Cl^–, NO₃^–, SO₄^2–, Na⁺, K⁺, Mg²⁺, and Ca²⁺), were also recorded. EC was found to be one of the major pollutants, although enrichment factors pointed to high contamination with SO₄^2–, K⁺, Mg²⁺_, Cr, Mn, and Pb; and extreme contamination with NO₃^– and Ca²⁺. The spatial and temporal variations, enrichment factors, toxicity, and sources of the chemical species detected in the soil are discussed.     

Estimation of land surface temperature using different retrieval methods for studying the spatiotemporal variations of surface urban heat and cold islands in Indian Punjab

Spatial patterns of land surface temperature (LST), surface urban heat island (SUHI), surface urban cold island (SUCI), and their seasonal variations during January (winter) and September (summer) were analyzed over the three cities of Indian Punjab (Balachaur, Ludhiana and Bathinda) using Landsat 5, 7 and 8 satellite data of the years 1991, 2001, 2011, and 2018. Urban hot spots and Urban Thermal Field Variance Index (UTFVI) were used to measure the ecological environment of these cities. Land surface temperature was retrieved from Landsat satellite data using Plank equation, mono-window algorithm (MWA), single-channel algorithm (SCA), and radiative transfer equation. The LST derived using these algorithms was validated with MODIS-LST product. The relationship between LST derived from Landsat 5, 7 and 8 using the four methods and MODIS-LST product was higher with the SCA algorithm (R²?>?0.75). Land surface temperature was significantly positively correlated with built-up but significantly negatively correlated with vegetation. The surface urban heat intensity was higher during September than January, and it was higher in Ludhiana followed by Bathinda and Balachaur, irrespective of the season. Besides built-up area and population density, soil moisture availability in surrounding rural areas has significant impact on increasing surface urban heat intensity during September than January. The SUCIs were formed in the center of Bathinda city during January 1991, but these were in Ludhiana and Balachaur cities during January 2011. The most critical areas for ecological environment based on UTFVI were identified and the critical UTFVI values (>?0.020) were highest in Bathinda city followed by Balachaur and Ludhiana cities. These results suggest that SUHIs and SUCIs are influenced by seasons and the mitigating plans to counteract the overheating of urban areas should be formulated taking into account soil moisture availability in surrounding rural areas, landscape pattern, seasonal variations, local climatic conditions, urban growth, and development plan etc.

     

Breakthrough Curves Characterization and Identification of an Unknown Pollution Source in Groundwater System Using an Artificial Neural Network (ANN)

Contamination of groundwater constrains its uses and poses a serious threat to the environment. Once groundwater is contaminated, the cleanup may be difficult and expensive. Identification of unknown pollution sources is the first step toward adopting any remediation strategy. The proposed methodology exploits the capability of a universal function approximation by a feed-forward multilayer artificial neural network (ANN) to identify the sources in terms of its location, magnitudes, and duration of activity. The back-propagation algorithm is utilized for training the ANN to identify the source characteristics based on simulated concentration data at specified observation locations in the aquifer. Uniform random generation and the Latin hypercube sampling method of random generation are used to generate temporal varying source fluxes. These source fluxes are used in groundwater flow and the transport simulation model to generate necessary data for the ANN model-building processes. Breakthrough curves obtained for the specified pollution scenario are characterized by different methods. The characterized breakthrough curves parameters serve as inputs to ANN model. Unknown pollution source characteristics are outputs for ANN model. Experimentation is also performed with different number of training and testing patterns. In addition, the effects of measurement errors in concentration measurements values are used to show the robustness of ANN based methodology for source identification in case of erroneous data.     

Experimental investigation of different-shaped microwave-heated potatoes: thermal and quality characteristics analysis for food preservation

Environmental Science and Pollution Research - Food materials are consumed for nutritional purposes in the form of fruits, vegetables, plants, and meat. These contain proteins, carbohydrates, and...     

Synthesis of highly fluorescent and water soluble graphene quantum dots for detection of heavy metal ions in aqueous media

Environmental Science and Pollution Research - Fluorescent graphene quantum dots (GQDs) are nanomaterials which possess unique properties that show great potential in different applications. In...     

A new system for groundwater contamination hazard rating of landfills

In developing countries, several unregulated landfills exist adjacent to large cities, releasing harmful contaminants to the underlying aquifer. Normally, landfills are constructed to hold three types of waste, namely hazardous waste, municipal solid waste, and construction and demolition waste. Hazardous waste and municipal solid waste landfills are of greater importance as these pose greater hazard to groundwater, in comparison with landfills holding waste from construction and demolition. The polluting landfills need to be prioritized to undertake necessary control and remedial measures. This paper assesses existing site hazard rating systems and presents a new groundwater contamination hazard rating system for landfills, which can be used for site prioritization. The proposed system is based on source-pathway-receptor relationships and evaluates different sites relative to one another. The system parameters have been selected based on literature. The Delphi technique is used to derive the relative importance weights of the system parameters. The proposed system is compared with nine existing systems. The comparison shows that the site hazard scores produced by the existing systems for hazardous waste, municipal solid waste, and construction and demolition waste landfills are of the same order of magnitude and tend to overlap each other but the scores produced by the proposed system for the three types of landfills vary almost by an order of magnitude, which shows that the proposed system is more sensitive to the type of waste. The comparison further shows that the proposed system exhibits greater sensitivity also to varied site conditions. The application of different systems to six old municipal solid waste landfills shows that whereas the existing systems produce clustered scores, the proposed system produces significantly differing scores for all the six landfills, which improves decision making in site ranking. This demonstrates that the proposed system makes a better tool for prioritization of landfills for adopting control measures and remediation.     

Soil carbon and nitrogen in 28-year-old land uses in reclaimed coal mine soils of Ohio

Carbon (C) and nitrogen (N) play an important role in the restoration of ecosystem functions of reclaimed mine soils (RMSs). Postreclamation land use in RMSs affects soil C and N pools and fluxes. We compared the effects of 28-yr-old postreclamation land uses (forest, hay, and pasture) on selected chemical properties of soil, and C and N pools in reference to undisturbed forest and moderately disturbed agricultural land use in southeastern Ohio. The electrical conductivity was higher in RMSs under hay than that in pasture and forest land uses. The RMSs under pasture, hay, and forest had moderately acidic, neutral to slightly alkaline, and slightly alkaline pH, respectively. In the 0- to 5-cm soil depth, soil organic C (SOC) was higher in RMSs under pasture by 99% and under hay by 52% over that under forest. Similarly, total nitrogen (TN) was higher in RMSs under pasture by 98% and under hay by 43% over that under forest. Aggregate-associated SOC concentration in the 0- to 5-cm depth decreased in the order of RMSs under hay > RMSs under pasture > RMSs under forest. The SOC pools in the 0- to 30-cm depth decreased in the order of RMSs under hay = RMSs under pasture > RMSs under forest = undisturbed forest = agriculture land use. Nitrogen pools followed a similar trend. Hay land use has a better potential for improving soil quality in RMSs by enhancing chemical properties and SOC and TN pools than forest or pasture land uses.     

Supply responses in tropical forestry: A Malaysian case study

The rapid exhaustion of Malaysia's commercial primaeval forest base has raised questions regarding the management and economic responses in the sector. The article assesses the institutional and management structure of Malaysian forestry which, together with the social and political barriers at work, prevent an orderly programme of harvesting and reforestation. The supply is then set out in terms of an econometric model, formulated both in static and dynamic terms to measure, among other things, the responses of output to price changes. The model, which is the first of its kind to be tested for the Malaysian forestry sector, is applied on three wood-based commodities — sawlogs, sawnwood and plywood. To learn of possible regional variations, the model is also applied to data of the country's three principal components — Peninsular Malaysia, Sarawak and Sabah. The results indicate that short-run price elasticities of supply are low, and in some cases, even contrary to expectations based on economic theory. Allowing for data inconsistencies, the slow responses of output to changes in price may be attributed to the method of wood disposal, its timing as well as the social and political barriers to entry at work in the sector.