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AbstractThe present studies report the use of an ecofriendly biomass Ficus religiosa in untreated (UFR) and xanthate treated (XFR) forms for the Cd (II) ions removal in a fixed bed column. FTIR, SEM‐EDS, BET surface area, and elemental analysis (CHNS) techniques were used to characterize the biosorbents. The acquired data supported FTIR findings regarding the nature of functional groups present in the materials. Packed bed continuous flow studies explored the effects of various parameters such as Cd (II) ion concentration (100 mg/L–300 mg/L), bed heights (5 cm–30 cm), pH (3–5), at a constant linear flow rate (~1.13 cm/min). The obtained S‐shaped breakthrough curves indicated the efficiency of the packed bed for the Cd (II) removal. Breakthrough time and exhaust times increased (67.5 min–390 min and 292.5 min–1852.5 min) (97.5 min–442.5 min and 345 min–1920 min) for unmodified and modified respectively with bed heights. The BDST, Thomas, and Yoon‐Nelson models were used to evaluate the experimental results. The Yoon‐Nelson model describes the breakthrough data more efficiently compared to other models. Under similar conditions, the modified material exhibited 400% increased capacity (55.20 mg/g) than that of unmodified material (13.33 mg/g). Thus, xanthate modification significantly enhanced the capacity for Cd (II) ions from aqueous solutions.Practitioner Points Xanthate modification of Ficus religiosa is an environmentally friendly process. Modified and unmodified materials were utilized for Cd (II) removal in fixed bed column process which is industrially viable process. Low inlet Cd (II) concentration at pH 5 and higher bed height favored the continuous flow process at fixed flow rate. Modification caused an increase of about 400% in the capacity of material.

An ecosystem in a cold climate river basin is vulnerable to the effects of climate change affecting permafrost thaw and glacier retreat. We currently lack sufficient data and information if and how hydrological processes such as glacier retreat, snowmelt and freezing-thawing affect sediment and nutrient runoff and transport, as well as N2O emissions in cold climate river basins. As such, we have implemented well-established, semi-empirical equations of nitrification and denitrification within the Soil and Water Assessment Tool (SWAT), which correlate the emissions with water, sediment and nutrients. We have tested this implementation to simulate emission dynamics at three sites on the Canadian prairies. We then regionalized the optimized parameters to a SWAT model of the Athabasca River Basin (ARB), Canada, calibrated and validated for streamflow, sediment and water quality. In the base period (1990-2005), agricultural areas (2662 gN/ha/yr) constituted emission hot-spots. The spring season in agricultural areas and summer season in forest areas, constituted emission hot-moments. We found that warmer conditions (+13% to +106%) would have a greater influence on emissions than wetter conditions (-19% to +13%), and that the combined effect of wetter and warmer conditions would be more offsetting than synergetic. Our results imply that the spatiotemporal variability of N2O emissions will depend strongly on soil water changes caused by permafrost thaw. Early snow freshet leads to spatial variability of soil erosion and nutrient runoff, as well as increases of emissions in winter and decreases in spring. Our simulations suggest crop residue management may reduce emissions by 34%, but with the mixed results reported in the literature and the soil and hydrology problems associated with stover removal more research is necessary. This modelling tool can be used to refine bottom-up emission estimations at river basin scale, test plausible management scenarios, and assess climate change impacts including climate feedback.

AbstractMicroalgal biotechnology could generate substantial amounts of biofuels with minimal environmental impact if the economics can be improved by increasing the rate of biomass production. Chlorella kessleri was grown in a small‐scale raceway pond and in flask cultures with the entire volume, 1% (v/v) at any instant, periodically exposed to static magnetic fields to demonstrate increased biomass production and investigate physiological changes, respectively. The growth rate in flasks was maximal at a field strength of 10 mT, increasing from 0.39 ± 0.06 per day for the control to 0.88 ± 0.06 per day. In the raceway pond the 10 mT field increased the growth rate from 0.24 ± 0.03 to 0.45 ± 0.05 per day, final biomass from 0.88 ± 0.11 to 1.56 ± 0.18 g/L per day, and maximum biomass production from 0.11 ± 0.02 to 0.38 ± 0.04 g/L per day. Increased pigment, protein, Ca, and Zn content made the biomass produced with magnetic stimulation nutritionally superior. An increase in oxidative stress was measured indirectly as a decrease in antioxidant capacity from 26 ± 2 to 17 ± 1 µmol antioxidant/g biomass. Net photosynthetic capacity (NPC) and respiratory rate were increased by factors of 2.1 and 3.1, respectively. Loss of NPC enhancement after the removal of magnetic field fit a first‐order model well (R2 = 0.99) with a half‐life of 3.3 days. Transmission electron microscopy showed enlarged chloroplasts and decreased thylakoid order with 10 mT treatment. By increasing daily biomass production about fourfold, 10 mT magnetic field exposure could make algal oil cost competitive with other biodiesel feedstocks. Bioelectromagnetics 33:298–308, 2012. © 2011 Wiley Periodicals, Inc.

Two chickpea genotypes viz. Bhakar-2011 (desi) and Noor-2013 (kabuli) were sown in soil filled pots supplied with low (0.3 mg kg-1) and high (3 mg kg-1 soil) zinc (Zn) under control (70% water holding capacity and 25/20 °C day/night temperature), drought (35% water holding capacity) and heat (35/30 °C day/night temperature) stresses. Drought and heat stresses reduced rate of photosynthesis, photosystem II efficiency, plant growth and Zn uptake in chickpea. Low Zn supply exacerbated adverse effects of drought and heat stresses in chickpea, and caused reduction in plant biomass, carbon assimilation, antioxidant activity, impeded Zn uptake and enhanced oxidative damage. However, adequate Zn supply ameliorated adverse effect of drought and heat stresses in both chickpea types. The improvements were more in desi than kabuli type. Adequate Zn nutrition is crucial to augment growth of chickpea plants under high temperature and arid climatic conditions.

Environmental quality indicators are crucial for responsive and cost-effective policies. The objective of the study is to examine the relationship between environmental quality indicators and financial development in Malaysia. For this purpose, the number of environmental quality indicators has been used, i.e., air pollution measured by carbon dioxide emissions, population density per square kilometer of land area, agricultural production measured by cereal production and livestock production, and energy resources considered by energy use and fossil fuel energy consumption, which placed an impact on the financial development of the country. The study used four main financial indicators, i.e., broad money supply (M2), domestic credit provided by the financial sector (DCFS), domestic credit to the private sector (DCPC), and inflation (CPI), which each financial indicator separately estimated with the environmental quality indicators, over a period of 1975-2013. The study used the generalized method of moments (GMM) technique to minimize the simultaneity from the model. The results show that carbon dioxide emissions exert the positive correlation with the M2, DCFC, and DCPC, while there is a negative correlation with the CPI. However, these results have been evaporated from the GMM estimates, where carbon emissions have no significant relationship with any of the four financial indicators in Malaysia. The GMM results show that population density has a negative relationship with the all four financial indicators; however, in case of M2, this relationship is insignificant to explain their result. Cereal production has a positive relationship with the DCPC, while there is a negative relationship with the CPI. Livestock production exerts the positive relationship with the all four financial indicators; however, this relationship with the CPI has a more elastic relationship, while the remaining relationship is less elastic with the three financial indicators in a country. Energy resources comprise energy use and fossil fuel energy consumption, both have distinct results with the financial indicators, as energy demand have a positive and significant relationship with the DCFC, DCPC, and CPI, while fossil fuel energy consumption have a negative relationship with these three financial indicators. The results of the study are of value to both environmentalists and policy makers.

Summary Separating edaphic impacts on tree distributions from those of climate and geography is notoriously difficult. Aboveground and belowground factors play important roles, and determining their relative contribution to tree success will greatly assist in refining predictive models and forestry strategies in a changing climate. In a common glasshouse, seedlings of interior Douglas‐fir (Pseudotsuga menziesii var. glauca) from multiple populations were grown in multiple forest soils. Fungicide was applied to half of the seedlings to separate soil fungal and nonfungal impacts on seedling performance. Soils of varying geographic and climatic distance from seed origin were compared, using a transfer function approach. Seedling height and biomass were optimized following seed transfer into drier soils, whereas survival was optimized when elevation transfer was minimised. Fungicide application reduced ectomycorrhizal root colonization by c. 50%, with treated seedlings exhibiting greater survival but reduced biomass. Local adaptation of Douglas‐fir populations to soils was mediated by soil fungi to some extent in 56% of soil origin by response variable combinations. Mediation by edaphic factors in general occurred in 81% of combinations. Soil biota, hitherto unaccounted for in climate models, interacts with biogeography to influence plant ranges in a changing climate.

The effect of light wavelengths on the physiological, biochemical and lutein content of the microalgal consortia Chlorella variabilis and Scenedesmus obliquus was evaluated using different light sources. Among different light treatments, cool-white fluorescent light produced the highest biomass of 673 mg L-1 with a specific growth rate of 0.75 day-1 followed by blue (500 mg L-1; 0.73 day-1). The chlorophyll content was enhanced under blue light (10.7 mg L-1) followed by cool fluorescent light (9.3 mg L-1), whereas the lutein productivity was enhanced under cool fluorescent light (7.22 mg g-1). Protein content of the microalgal consortia was enhanced under all light treatments with the highest protein accumulation under cool-white fluorescent light (~56% of dry mass) closely followed by amber light (52% of dry mass), whereas the carbohydrate content was higher under amber light (~35% of dry mass). The results revealed that the consortia could grow well on diluted dairy wastewater thereby reducing the cost of algal production when compared with the use of inorganic media and a two-phase culture process utilizing cool fluorescent and amber light could be employed for maximizing algal biomass and nutrient composition with enhanced lutein production. The study also emphasizes on the economic efficiency of LED lights in terms of biomass produced based on the modest electricity consumed and the importance of using amber light for cultivating microalgae for its nutrient content which has seldom been studied.

At present, Artemisia annua L. is the major source of artemisinin production. To control the outbreaks of malaria, artemisinin combination therapies (ACTs) are recommended, and hence an ample amount of artemisinin is required for ACTs manufacture to save millions of lives. The low yield of this antimalarial drug in A. annua L. plants (0.01-1.1%) ensues its short supply and high cost, thus making it a topic of scrutiny worldwide. In this study, the effects of root endophyte, Piriformospora indica strain DSM 11827 and nitrogen fixing bacterium, Azotobacter chroococcum strain W-5, either singly and/or in combination for artemisinin production in A. annua L. plants have been studied under poly house conditions. The plant growth was monitored by measuring parameters like height of plant, total dry weight and leaf yield with an increase of 63.51, 52.61 and 79.70% respectively, for treatment with dual biological consortium, as compared to that of control plants. This significant improvement in biomass was associated with higher total chlorophyll content (59.29%) and enhanced nutrition (especially nitrogen and phosphorus, 55.75 and 86.21% respectively). The concentration of artemisinin along with expression patterns of artemisinin biosynthesis genes were appreciably higher in dual treatment, which showed positive correlation. The study suggested the potential use of the consortium P. indica strain DSM 11827 and A. chroococcum strain W-5 in A. annua L. plants for increased overall productivity and sustainable agriculture.