Scenario-based urban growth allocation in a rapidly developing area: a modeling approach for sustainability analysis of an urban-coastal coupled system

Being located in an urban-coastal coupled system, the Hashtpar City is one of the most attractive areas for urban construction, tourism, agricultural activities and environmental protection in northern Iran. To resolve the issues between land developers and environmental conservation agencies, we conducted a scenario-based urban growth allocation procedure through the SLEUTH model. The scenarios consisted of ‘business as usual’, ‘managed urban growth’ and ‘environmentally sound growth’ that were introduced by modification of model parameters and exclusion layer. The resultant urban growth arrangements were compared for composition and configuration attributes of landscape patterns. According to the results, the pattern of urbanized lands under managed urban growth option demonstrated better connectivity and compactness of urban patches, while the two other scenarios generated a highly fragmented pattern. The managed urban growth can be considered as a compromised solution between other scenarios since it simultaneously takes into accounts both developers and environment protectors points’ of views. On this basis, a combination of centralized and decentralized urban land use planning is a recommended strategy for our urban-coastal environment to fulfill the purposes of a sustainable development process. The findings of the present article suggest that further expansion of the major urban core in the targeted area should be prohibited since it can lead to an urban patch with considerable physical size and noticeable ecological footprint.     

Characterization of titanium oxide optical band gap produced from leachate sludge treatment with titanium tetrachloride

Environmental Science and Pollution Research - This study investigated the coagulation performance of titanium tetrachloride (TiCl4) for leachate treatment and preparation of titanium oxide (TiO2)...     

Application of chemical oxidation to remediate HCH-contaminated soil under batch and flow through conditions

This is the first study describing the chemical oxidation of hexachlorocyclohexanes (HCHs) in contaminated soil under water saturated and unsaturated flow through conditions. Soil contaminated with β-HCH (45 mg kg^?1) and γ-HCH (lindane, 25 mg kg^?1) was sampled from former lindane waste storage site. Efficiency of following treatments was tested at circumneutral pH: H₂O₂ alone, H₂O₂/Fe^II, Na₂S₂O₈ alone, Na₂S₂O₈/Fe^II, and KMnO₄. Experimental conditions (oxidant dose, liquid/solid ratio, and soil granulometry) were first optimized in batch experiments. Obtained results revealed that increasing dose of H₂O₂ improved the oxidation efficiency while in Na₂S₂O₈ system, maximum HCHs were removed at 300 mM. However, oxidation efficiency was slightly improved by Fe^II-activation. Increasing the solid/liquid ratio decreased HCH removal in soil samples crushed to 500 μm while an opposite trend was observed for 2-mm samples. Dynamic column experiments showed that oxidation efficiency followed the order KMnO₄ > Na₂S₂O₈/Fe^II > Na₂S₂O₈ whatever the flow condition, whereas the removal extent declined at higher flow rate (e.g., ~50% by KMnO₄ at 0.5 mL/min as compared to ~30% at 2 mL/min). Both HCH removal and oxidant decomposition extents were found higher in saturated columns than the unsaturated ones. While no significant change in relative abundance of soil mineral constituents was observed before and after chemical oxidation, more than 60% of extractable organic matter was lost after chemical oxidation, thereby underscoring the non-selective behavior of chemical oxidation in soil. Due to the complexity of soil system, chemical oxidation has rarely been reported under flow through conditions, and therefore our findings will have promising implications in developing remediation techniques under dynamic conditions closer to field applications.     

Treatment of hydrocarbon contamination under flow through conditions by using magnetite catalyzed chemical oxidation

Soil pollution by hydrocarbons (aromatic and aliphatic hydrocarbons) is a major environmental issue. Various treatments have been used to remove them from contaminated soils. In our previous studies, the ability of magnetite has been successfully explored to catalyze chemical oxidation for hydrocarbon remediation in batch slurry system. In the present laboratory study, column experiments were performed to evaluate the efficiency of magnetite catalyzed Fenton-like (FL) and activated persulfate (AP) oxidation for hydrocarbon degradation. Flow-through column experiments are intended to provide a better representation of field conditions. Organic extracts isolated from three different soils (an oil-contaminated soil from petrochemical industrial site and two soils polluted by polycyclic aromatic hydrocarbon (PAH) originating from coking plant sites) were spiked on sand. After solvent evaporation, spiked sand was packed in column and was subjected to oxidation using magnetite as catalyst. Oxidant solution was injected at a flow rate of 0.1 mL min^?1 under water-saturated conditions. Organic analyses were performed by GC–mass spectrometry, GC–flame ionization detector, and micro-Fourier transform infrared spectroscopy. Significant abatement of both types of hydrocarbons (60–70 %) was achieved after chemical oxidation (FL and AP) of organic extracts. No significant by-products were formed during oxidation experiment, underscoring the complete degradation of hydrocarbons. No selective degradation was observed for FL with almost similar efficiency towards all hydrocarbons. However, AP showed less reactivity towards higher molecular weight PAHs and aromatic oxygenated compounds. Results of this study demonstrated that magnetite-catalyzed chemical oxidation can effectively degrade both aromatic and aliphatic hydrocarbons (enhanced available contaminants) under flow-through conditions.     

Effect of Bimetallic Soybean Oil Based Polymer on Growth and Plasma Membrane H+-ATPase Activity Among Fungi

In view of bio-inorganic importance, iron and zinc incorporated soybean oil based polymer was prepared by condensation polymerization of oil based fatty amide polyole, sebacic acid, zinc acetate and ferric chloride in a process initiated by sodium ethoxide. Microwave assisted synthesis was used throughout the reaction as it is ecofriendly and requires minimal usage of solvents. Physical techniques such as FT-IR and ¹HNMR have been used to establish the structure of the polymers. Standard laboratory methods like acid value, saponification value, iodine value, specific gravity and viscosity were used to study the chemical diversity of each product. Thermo gravimetry/differential thermal analyzer was used to analyse the thermal behavior of polymer. The synthesized compounds were subjected to biological study. The observed fungicidal characteristics of synthesized compounds indicate that these compounds might be promising antifungal agents defining a new class of antimycotics. The polymers were used in preparation of films which can be used as protective packaging material of edible items.     

Copper modulates non-enzymatic antioxidants in the freshwater fish Channa punctata (Bloch) exposed to deltamethrin

The assessment of the ecotoxicological risks caused by pesticides to ecosystems are based on data on the toxicity and effects of pesticide preparations to non-target organisms like fish. Deltamethrin is a widely used pesticide based on pyrethroids, which is reported to be extremely toxic to fish species. Modulatory effect of copper pre-exposure (10 ppb) on deltamethrin (0.75 microg l-1)-induced oxidative stress was investigated in freshwater fish Channa punctata (Bloch). Non-enzymatic antioxidants were studied as biomarkers of exposure to deltamethrin and possible protection afforded by copper pre-exposure. Glutathione levels were reduced significantly (P<0.05) in liver of copper-acclimatized deltamethrin-exposed group when compared with deltamethrin-exposed groups. The total thiol levels of copper-acclimatized deltamethrin-exposed group was significantly lowered (P<0.01) in liver when compared with deltamethrin-exposed group, while non-protein thiol levels recorded a significant (P<0.01) increase in liver of copper-acclimatized deltamethrin-exposed group when compared with deltamethrin-exposed group. The lipid peroxidation levels of copper-acclimatized deltamethrin-exposed groups were significantly lowered (P<0.01) in liver when compared with deltamethrin-exposed group. Deltamethrin is known to induce toxic responses by generating reactive oxygen species and to neutralize its toxic effect various non-enzymatic antioxidants were found to be modulated thus implicating their role as biomarkers in pollution control programmes.     

Mode choice model for vulnerable motorcyclists in Malaysia

OBJECTIVE: In developing countries, motorcycle use has grown in popularity in the past decades. Commensurate with this growth is the increase in death and casualties among motorcyclists in these countries. One of the strategic programs to minimize this problem is to reduce motorcyclists exposure by shifting them into safer modes of transport. This study aims to explore the differences in the characteristics of bus and motorcycle users. It identifies the factors contributing to their choice of transport mode and estimates the probability that motorcyclists might change their travel mode to a safer alternative; namely, bus travel. METHODS: In this article, a survey of 535 motorcycle and bus users was conducted in seven districts of Selangor state, Malaysia. A binary logit model was developed for the two alternative modes, bus and motorcycle. RESULTS: It was found that travel time, travel cost, gender, age, and income level are significant in influencing motorcyclists' mode choice behavior. The probability of motorcycle riders shifting to public transport was also examined based on a scenario of a reduction in bus travel time and travel cost. CONCLUSIONS: Reduction of total travel time for the bus mode emerges as the most important element in a program aimed at attracting motorcyclists towards public transport and away from the motorcycle mode.     

Impact of economic capabilities and population agglomeration on PM2.5 emission: empirical evidence from sub-Saharan African countries

Environmental Science and Pollution Research - The utilization of economic capabilities to raise production in the economy enhances the industrial activities and use of transportation. These...     

A global perspective on the biology,impact and management of Chenopodium album and Chenopodium murale: two troublesome agricultural and environmental weeds

Environmental Science and Pollution Research - Chenopodium album and C. murale are cosmopolitan, annual weed species of notable economic importance. Their unique biological features, including high...