Total Environment Research Themes最新文献

A comprehensive geochemical investigation was carried out to characterise the sediment and water seeping out from mud volcano in Kampung Meritam, Limbang, northern Borneo. Chemical analysis included major oxides, trace metals, rare earth elements, and major ions. Interpretation of results reveals that the geochemical composition of sediment samples is originated from sedimentary provenance particularly Setap Shale, which is the dominant formation present in this region. The concentration of trace elements and major oxides were used to identify the origin and weathering nature of sediment. SiO₂ is the dominant major oxide present in the sediment samples with an average concentration of 58.24%. Whereas for trace metals, Ba is dominating with an average concentration of 263 ppm. Environmental pollution indices such as contamination factor, geoaccumulation index, and enrichment factor were used to assess the contamination level of mud volcanic sediments. Hydrochemistry of mud volcano suggests that the water is derived from ionic enriched solute, indicated by Na-Cl water type. The average concentration of Na⁺ and Cl⁻ is 987 mg/L and 10457.50 mg/L. The ionic ratios suggest that water–rock interaction including carbonate mineral dissolution is the predominant process that controls the water chemistry. Gibbs diagram shows that the water is influenced by the dissolution of evaporite minerals. Thermodynamic stability and saturation index were used to evaluate the mineral stability and saturation condition during weathering. Ca²⁺ and Mg²⁺ were released into the water due to the reverse ion exchange process, which was supported by XRD results. Higher ionic strength and Log pCO₂ values suggest longer residence time of water in the aquifer matrix and therefore significant dissolution of enriched solute due to the intensive water–rock interaction. The outcome of this study would provide the basis for a better understanding on the geochemical characteristics of Meritam mud volcano in Northern Borneo.

In this study, the most important parameters governing metal mobility were first identified based on laboratory batch sequential extraction and isotope dilution experiments with three types of samples, i.e., surface soil, underlying soil (depth > 1.0 m) and soakaway sediment collected at Tokyo (n = 3). The selected parameters were first brought to normalization step, where each parameter was transformed into a 0–100 % scale, followed by assigning relative weight factors reflecting the importance of each parameter for metal retention property. Heavy Metal Retention Index (HMRI) then combined the different parameters in a unique number (index) to facilitate the comparison. In this way, hierarchical levels of normalized factors were obtained in the form of HMRI to make the decision. Properties that were evaluated in this study were of three types: i) classical physicochemical properties, i.e., the content of clay, organic, Fe-Mn oxide, silicates and CEC and thus varied with a particular sample; ii) specific variables for each metal like isotopic exchangeability (% E-value), sorption coefficient (K_d) and exchangeable fraction which varies with each metal type viz. Cu, Zn and Pb; and iii) integrated properties (both sample-specific and metal-specific properties) using which HMRI were developed. Finally, all these results were compared with column results obtained after 10 days of continuous leaching with artificial road runoff (ARR), prepared in the laboratory using highway road dust and deionized water (liquid/solid ratio = 25 L/kg).

In addition to providing advantages, scientific discoveries can pollute the environment in negative ways. The impact of acid treatment on the adsorption ability of earthenware clays to remove malachite green dye (MGD) was studied. This project aims to identify a cost-effective method for cleaning up textile effluent. Adjustments were made to dose, temperature, experiment time, concentration, and stirring speed to maximise dye removal from wastewater. At a pH of 4.5 and a temperature of 27 °C, the highest dye adsorption was observed to be 86%. The Frenundlich adsorption isotherm best matched the process of adsorption; however, the pseudo-second-order kinetic model best explained the kinetics study. The best match of the Elovich adsorption isotherm was reported for acid clays with high R2 values.

One of the most significant cereal crops in the world, maize (Zea mays L.), is used for food, feed, and energy. Inoculation with plant-growth-promoting rhizobacteria (PGPR) could be offered as a substitute method for maize production that is sustainable in contemporary agricultural systems and would reduce the need of chemical fertilisers and pesticides. In this study, we made an effort to collect enough information to support our assertion that the best PGPRs for the maize crop specifically are Azospirillum lipoferum, Pseudomonas fluorescens, Pseudomonas putida, and Bacillus subtilis. On maize crops of the AXE* and PMH1 varieties, PGPRs (Azospirillum lipoferum, Pseudomonas fluorescens, Pseudomonas putida, and Bacillus subtilis) are found to have a significant growth-promoting effect. Results showed that compared to control, A. lipoferum, B. subtilis, P. putida, and P. fluorescens treatment improved morphological, biochemical, and harvest characteristics. We have proposed with the aim of gathering more evidence that Pseudomonas putida and Azospirillum lipoferum bacteria can be deemed maize specific PGPR since out of all the strains under research, better results were obtained with these two strains.

Termites are one of the most abundant macroinvertebrates in the world having versatile roles in the ecosystem. The polymeric substances produced during the process of foraging and excretion of the termite ecosymbionts play major role in soil aggregation. In consequence, the termite ecosystem plays a vital role in improving soil health and nutrient. The present study investigates the potential bacteria isolated from termite mound soil that can decolourize synthetic dye. The result depicts that decolourization efficiency was 94.46, 91.64 and 89.67 per cent when Lysinibacillus fusiformis was cultured in the broth amended with congo red at 3 different concentrations say, 250, 500 and 1000 mg L⁻¹ respectively. Likewise, Mesobacillus jeotgali has an efficiency of 85.74, 82.04 and 79.27 per cent with methylene blue dye at 6 days after inoculation at dye concentrations of 250, 500 and 1000 mgL⁻¹ respectively. When immobilized cells Lysinibacillus fusiformis and Mesobacillus jeotgali were employed, the decolourization efficiency was found to be 96.04, 93.73 and 88.64 per cent with congo red and 91.56, 85.15 and 80.84 per cent with methylene blue respectively at 3 days after inoculation for dye concentrations 250, 500 and 1000 mg L⁻¹. Azoreductase activity was recorded highest of 0.089 units mg⁻¹ without immobilization and 0.093 units mg⁻¹ with immobilization. Subsequent FT-IR analysis showed that functional group modifications with Lysinibacillus fusiformis and Mesobacillus jeotgali was observed at 12 and 24 h after inoculation respectively.

The present study intends to evaluate and characterize the river water quality of the Karamana river estuary, one of the significant rivers on India's west coast, utilizing a combination of the Water quality index (WQI), multivariate statistical, and GIS approaches. The river's source is at Agastyar Koodam on the southernmost extremity of the Western Ghats, and it serves as a significant source of water for Trivandrum's residents' domestic and drinking water needs before mixing with the Arabian Sea on India's west coast. Analyzing water quality is one of the most crucial components of surface water investigations. The level of pollution is significantly influenced by the water quality. By analysing water samples, an attempt is made to comprehend the water quality of the Karamana River Basin, and suggestions are offered for the prudent use and managing of water resources. Twenty water samples were taken from various sampling locations in order to evaluate the water quality. The estuarine water environment is controlled by the physico-chemical parameters, main ions, and trace elements of the water quality attributes. The quality of the water was assessed using the following parameters: pH, TDS, Ca, Mg, Na, K, Cl, SO4, HCO3, CO_3, NO₃, and Trace elements (Fe, Cu, Cr, Ni, CO, Cd and Zn). The majority of the samples were classified as having fair to good water quality, as determined by the WHO-permitted standards used to construct the water quality index (WQI). The quality of water is seen to be fair to marginal in the midstream to downstream zone, where anthropogenic activities are predominant.

Microplastic pollution is getting worse day by day; there is no ecosystem that’s void of their presence. Microplastics accumulating in marine ecosystems can destroy the stability of that particular ecosystem in many ways. As humans are notorious for consuming and exploiting marine resources, microplastics from the ocean reach humans through the food chain, which could cause ineffable side effects. One of the potential ways for microplastics from marine environments to reach humans is through sea salts taken from solar salt pans, and commercial salts are packaged from refined sea salts. Since the dawn of civilization, humans have used salt in their cooking. Table salts are an indispensable ingredient that gets added to enhance the deliciousness of food and is also used as a preservative, so adulteration or contamination in salts should be critically evaluated and rectified. Hence, this study aimed to analyse the presence of microplastics in sea salts from solar saltpans in some regions of Tamil Nadu and some well-known brands of commercial salts and characterise the type of polymer using FT-IR spectroscopy. This is a baseline study to identify the presence of microplastics in sample salts. This study confirmed the presence of microplastic in all the salt samples taken from salt pans and two brands of commercial salt, which numbered <350 polymer fragments, which include different polymer types. First report on the presence of certain polymer types, including acrylic, acrylonitrile butadiene styrene (ABS), high-density polyethylene (HDPE), polytetrafluoroethylene (PTFE), and polycarbonate (PC), among MPs in India. Dominance was shown by polyethylene, as it was present in most of the samples taken from different places. A detailed study on how microplastic contamination affects the health of human beings and how to effectively prevent microplastic contamination in human consumables is warranted.

The main objective of this study is eco-environmental evaluation of cucumber and sunflower productions in Holeylan, Ilam province of Iran. The data was collected from cucumber and sunflower farms using face to face interview and questionnaire method. The results showed that the potential of global warming for cucumber and sunflower productions was 8554.97 and 2417.42 kgCO₂eqha⁻¹, respectively. Total CO₂ emission of cucumber and sunflower productions were calculated 4997.75 and 1129.34 kgha⁻¹, respectively. Electricity, diesel fuel and nitrogen fertilizer were the main source of emission in cucumber and sunflower productions. The results revealed that the CO₂ emission from electricity was higher than other inputs because of using some old electric pumps in the irrigation system. The carbon efficiency factor for cucumber and sunflower cultivation were calculated 10.71 and 2.06, respectively. The results of economic analysis indicated that the total production cost were 7615.83 and 5050.44 $ha⁻¹, the gross domestic product were 11,550 and 7830 $ha⁻¹, the fixed cost were 1224.35 and 1846.26 $ha⁻¹, the variable cost were 6769.57 and 3826.09 $ha⁻¹ and also the benefit to cost ratio were 1.51 and 1.55 for cucumber and sunflower productions, respectively. Finally, the sustainability index was calculated 9.71 and 1.06 for cucumber and sunflower productions, respectively. Decreasing the electricity consumption by using appropriate water pump and applying proper management methods can decrease the electricity consumption in cucumber and sunflower productions.

Submarine groundwater discharge (SGD) delivers significant nutrients from inland to oceans. Nevertheless, SGD-related nutrient fluxes have been unnoticed in the Cuddalore coast of Tamil Nadu, Bay of Bengal, exposed to thoughtful environmental issues. The present attempt was to assess SGD-aided radon and nutrient fluxes. Groundwater samples were collected and analyzed for pH, electrical conductivity, total dissolved solids, salinity, radon, nitrogen, phosphorous, and silica. The radon in groundwater samples lies between 0.1 and 7.9, with an average of 2.2 Bq L⁻¹. The SGD flux calculated from radon mass balance ranges from 0.11 to 15.03, with an average of 3.42 m d⁻¹. The SGD-associated dissolved nutrients were 4292.0, 184.0, and 1442.2 µ mol L⁻¹ d⁻¹ for dissolved inorganic nitrogen, dissolved inorganic phosphate, and dissolved silica, respectively. The quantum of SGD and accompanying nutrient fluxes were prejudiced by precipitation, hydraulic gradient, and aquifer environments like oxic and anoxic.

Intensive cultivation of vegetables and scarcity of clean irrigation water has resulted in the increased use of wastewater for irrigation worldwide, especially in developing countries. In this review, we analyze and outline the drawbacks of such practice to provide information on ecological and human health risk associated with the practice and suggested a way forward. For our review to reflect the best practice and technological advances in state-of-the-art terms, articles published in the last decade were considered. The review started by highlighting the growing concern of water scarcity in developing countries, the sources of wastewater, how farmers utilize the wastewater for irrigation, and limitations of existing studies. It then proceeds with in-depth look at the benefits of using wastewater for irrigation, recent diseases discovered due to wastewater irrigation, existing knowledge on the alteration of soil physical and chemical properties resulting from wastewater irrigation, heavy metals contamination of soil and food crops due to wastewater irrigation, risk assessment associated to wastewater irrigation, and then finally we proposed a novel approach of using wastewater for irrigation. In terms of benefits, more emphasis was focused on economic and environmental benefits, while also highlighting benefits to human health. We have also highlighted wastewater-borne diseases, paying more attention to recent ones that are of acute and chronic risks. In terms of the alteration of soil’s physical and chemical properties, more emphasis was put on its effects on soil fertility and productivity. The review critically revealed the heavy metals contaminating soil and food crops because of wastewater irrigation, and risk assessment also discoursed in detail. In the end, special consideration was given to the formulation of a novel approach to using wastewater for irrigation in a sustainable way, while avoiding or at least minimizing associated human health risk that are becoming rampant, especially in developing countries.