Uptake and depuration of 131I from labelled diatoms (Skeletonema costatum) to the edible periwinkle (Littorina littorea)

Uptake and depuration of (131)I into winkles through consumption of the diatom Skeletonema costatum is described. The work follows on from previous studies that investigated the uptake of iodine into winkles from seawater and seaweed. Incorporation of (131)I in S. costatum from labelled seawater followed linear first-order kinetics with an uptake half-time of 0.40 days. Iodine uptake in winkles from labelled S. costatum also followed linear first-order kinetics, with a calculated equilibrium concentration (C(infinity)) of 42Bqkg(-1) and a transfer factor (TF) of 1.1x10(-4) with respect to labelled diatom food. This TF is lower than that observed for uptake of (131)I in winkles from labelled seaweed. For the depuration stage, a biphasic sequence with biological half-lives of 1.3 and 255 days was determined. The first phase is biokinetically important, given that winkles can lose two-thirds of their activity during that period. This study shows that, whilst winkles can obtain radioactive iodine from phytoplankton consumption, they do not retain the majority of that activity for very long. Hence, compared with other exposure pathways, such as uptake from seawater and macroalgae, incorporation from phytoplankton is a relatively minor exposure route.     

New perspectives on the energy return on (energy) investment (EROI) of corn ethanol

Research on corn ethanol is overly focused on whether corn ethanol is a net energy yielder and, consequently, has missed some other fundamental issues, including (1) whether there is significant error associated with current estimates of the EROI of corn ethanol, (2) whether there is significant spatial variability in the EROI of corn ethanol production, (3) whether yield increases will translate linearly to increases in EROI, (4) the extent to which assumptions about co-product credits impact the EROI of corn ethanol, and (5) how much of the ethanol production from biorefineries is net energy. We address all of these concerns in this research by: (1) performing a meta-error analysis of the calculation of EROI, (2) calculating the EROI for 1,287 counties across the United States, and (3) performing a sensitivity analysis for the values of both yield and co-products within the calculation of EROI. Our results show that the average EROI calculated from the meta-error analysis was 1.07 ± 0.2, meaning that we are unable to assert whether the EROI of corn ethanol is greater than one. The average EROI calculated across 1,287 counties in our spatial analysis was 1.01, indicating that the literature tended to use optimal values for energy inputs and outputs compared to the average conditions across the Unites States. Increases in yield had a trivial impact on EROI, while co-product credits had a large impact on EROI. Based on our results from the spatial analysis and the location of biorefineries across the United States, we conclude that the net energy supplied to society by ethanol is only 0.8% of that supplied from gasoline. Recent work indicates that only energy sources extracted at EROIs of 3:1 or greater have the requisite net energy to sustain the infrastructure of the transportation system of the United States. In light of this work, we conclude that production of corn ethanol within the United States is unsustainable and requires energy subsidies from the larger oil economy.     

Uptake and depuration of 131I by the edible periwinkle Littorina littorea: uptake from labelled seaweed (Chondrus crispus)

Uptake and depuration experiments of (131)I from labelled seaweed (Chondrus crispus) by the edible periwinkle Littorina littorea have been performed. Radioiodine concentrations in winkles during uptake followed first-order kinetics with an uptake half-time of 1 day, and a calculated equilibrium concentration (C(infinity)) of 21 000 Bq kg(-1) resulting in a transfer factor of 0.07 with respect to the labelled seaweed used as food. For depuration, a biphasic sequence with biological half-lives of 1 and 24 days was determined. The results suggest that in general, iodine turnover in periwinkles is slower than observed for other molluscs (monophasic biological half-lives in the order of 2-3 days). Both environmental media, food and seawater, can be significant sources of radioiodine for the winkle.     

The accumulation of plutonium by the edible winkle (Littorina littorea L.)

Laboratory experiments were carried out to measure the accumulation of ²³⁷Pu by the edible winkle from labelled sea water, food (seaweed), and silt. The equilibrium whole body concentration factor for ²³⁷Pu accumulation from sea water at 10°C was estimated as 34 with a biological half-time of 9 d. After 50 d accumulation, 83% of the measured whole body activity was present on the shell. In the flesh, the major sites for accumulation were the head/foot complex and the digestive gland. Depuration was found to be biphasic with components having half-times of 10 and 193 d respectively. Pu loss, following uptake from labelled Fucus spiralis, was biphasic with half-times of 1 and 69 d for the two components. Assimilation efficiency was tentatively estimated as 7%. Pu accumulation from labelled silt was low with an estimated transfer factor of 0.004; Pu loss was biphasic, with half-times similar to those for the seaweed experiment. Comparison of the laboratory-derived results with those for winkles from the environment showed that the food pathway was the main route for Pu accumulation, with the ingestion of silt playing a critical role in determining the final flesh Pu burden.     

Heterogenous impacts of components in urban energy metabolism: evidences from gravity model

Environment, Development and Sustainability - The undergoing rapid urbanization is bringing dramatic economic development and social improvement for cities, but also a series of problems associated...     

Energy metabolism and growth of Monoporeia affinis Lindstr. in the Northern Lake Krivoe (Karelia)

The physiological method for estimating production based on the relationship between growth and energy metabolism has been used for calculating model growth curves for the amphipod Monoporeia affinis and comparing them with the results of field studies. Calculations demonstrated that the physiological growth curves fit the results of field observations best under certain conditions which have zoological sense: the growth curve should reflect the actual maximum body size of an animal in the given population, the duration of the life cycle, and the time required for reaching the reproductive size.     

Ecological and genetic characteristics of the distribution of <Emphasis Type="Italic">Bradybaena fruticum</Emphasis> Mull. (mollusca,gastropoda, pulmonata) in a forest-steppe landscape

The distribution pattern of the gastropod Bradybaena fruticum has been studied in a forest-steppe landscape. Analysis of the frequencies of polymorphic biochemical and conchological characters has yielded preliminary results on the characteristics of the species population structure whose formation was determined by a set of natural and anthropogenic factors.Translated from Ekologiya, No. 1, 2005, pp. 39–47.Original Russian Text Copyright © 2005 by Snegin.     

A test of environmental Kuznets curve (EKC) for carbon emission and potential of renewable energy to reduce green house gases (GHG) in Malaysia

This study investigates the presence of environmental kuznets curve (EKC) for green house gases (GHG) measured by CO₂ emission in Malaysia for the period 1970 to 2011. The study also examines the potential of the renewable source of energy to contain GHG. The long-run significant positive coefficient of GDP indicates that the GHG are increasing with economic growth while the insignificant coefficient on GDP square rejects the EKC transition. These results indicate a high GDP level for the EKC turning point for Malaysia. Therefore, it can be stated that only economic growth cannot reverse the environmental degradation in Malaysia. The government should have to come up with some policy measures to achieve CO₂ emission reduction targets that Malaysia has pledged to achieve in Paris Submit (2015). The renewable energy production is found to have significant negative effect on CO₂ emission. So government should focus on the renewable source of energy production and should frame a special policy for renewable energy production.     

Uptake and depuration of 131I by the edible periwinkle Littorina littorea: uptake from seawater

Uptake and depuration experiments for the edible periwinkle Littorina littorea have been performed using 131I-labelled seawater. Throughout the experimental phase the winkles were fed on unlabelled Chondrus crispus. 131I concentrations in winkles during uptake followed linear first-order kinetics with an uptake half-time of 11 days, whereas for depuration a triphasic sequence with biological half-lives of 4, 23 and 56 days was determined. In general, iodine turnover in winkles via labelled seawater appears to be slower than observed for other molluscs (2-3 days). Most of the activity prior to and after depuration is found to be in the shell, with indications that shell and soft parts accumulate and depurate 131I at a similar rate. The operculum displays the highest specific activity of all fractions with a concentration factor of 750 l kg(-1). Concentration factors for whole winkle, shell, soft parts and digestive gland are in the order of 40-60 l kg(-1), higher than the IAEA recommended CF value for iodine in molluscs of 10 l kg(-1). The 131I CF in winkles is closer to that of the conservative radionuclides 99Tc and 137Cs than the CF of the particle reactive radionuclides (239,240)Pu and 241Am.     

SWOT analysis of renewable energy sector in Mazowieckie Voivodeship (Poland): current progress,prospects and policy implications

Environment, Development and Sustainability - Renewable energy (RE) plays an increasingly important role in the economy of almost every country in the world. In order to examine the state of...     

Analysis of two schemes using micro hydroelectric power (MHPs) in the Amazon with environmental sustainability and energy and economic feasibility

A major problem for sustainable development in the Amazon is the difficulty of supplying electric power to isolated communities, which represent a considerable share of the population. This problem has been a major obstacle to productive activities (especially extractive and agricultural) in such communities, thus significantly contributing to rural drift and creating social problems in larger cities. In that case, one way to supply electric power would be to use the huge network of small rivers in the region by implementing Micro Hydroelectric Power Plants (MHPs). However, this type of hydropower project requires a set of technical assessments in order to obtain better value for its cost-effectiveness from the perspective of sustainable development. Thus, based on a survey of energy demand and the local hydrological and topographical characteristics, two possible MHP designs for the hydrological site under analysis were suggested. Assessments of hydropower, economic and environmental aspects were developed. MHP designs were compared with the diesel generator design of the community under focus. Comparison showed that the MHP designs are feasible in terms of energy to meet local demand; economically, they are more feasible than the diesel generator and are environmentally sustainable, mainly because such designs involve low-head, run-of-river MHPs and the flooded areas were simulated and are not larger than 0.02 km². Therefore, the information provided by these assessments constitutes important data, serving as subsidies for MHP implementation projects, which shall contribute to sustainable development in the region.     

Physical resuspension and vertical mixing of sediments on a high energy continental margin (Sydney, Australia)

Four sediment cores from the continental margin adjacent to Sydney were analyzed for 210Pb, 137Cs, trace metals (Ag, Cd, Co, Cu, Mn, Ni, Pb, Zn), iron, dry bulk density, mud and moisture content. The concentrations of trace metals in the total sediment are low at all sites, although slightly elevated concentrations of Ag, Cu, Pb and Zn are present in the fine fraction of sediment (< 62.5 microns) near a major ocean outfall. Concentrations of trace metals in the fine fraction of sediment are similar in the upper 10-15 cm, indicating strong vertical mixing of the sediments, whereas an upward coarsening grain size in the upper 1-3 cm of sediment supports physical resuspension during storms. Sediment accumulation rates on the middle shelf adjacent to Sydney were estimated from downcore profiles of 210Pb and 137Cs and range between 0.2 and 0.4 cm yr-1. Although the mass fluxes of Cu, Pb and Zn within a distance of 2 km from the outfall (up to 36.1, 30.8 and 86.2 micrograms cm-2 yr-1, respectively) are greater than 20 km north of the outfall (< 23.5 micrograms cm-2 yr-1), the low concentrations of trace metals in sediments near the outfall support an efficient dispersal of anthropogenic contaminants on this continental margin.     

Molecular biomarkers of energy metabolism in mussels under anthropogenic pollution of Peter the Great Bay, the Sea of Japan

The functional state of the indicator species, the Gray mussel Crenomytilus grayanus (Bivalvia), has been analyzed in five areas of Peter the Great Bay exposed to anthropogenic pollution. The following indices of the state of mussels have been used: molecular biomarkers of energy metabolism—Na⁺,K⁺-ATPase, Mg²⁺-ATPase, and total ATPase activity—as well as the level of lipid peroxidation (LPO) and glutathione concentration in the hepatopancreas, gills, and gonads of mussels. The activity of ATPases, LPO level, and glutathione concentration significantly change in mussels from polluted areas relative to those in mussels from a conventionally unpolluted area (a bay in the Far Eastern State Marine Reserve). The molecular biomarkers used in the study provide reliable information on animal metabolism in impact areas. With consideration of the data obtained, it is concluded that the state of mussels in polluted areas is impaired.     

Efficient monitoring and control of wind energy conversion systems using Internet of things (IoT): a comprehensive review

Environment, Development and Sustainability - The necessity of making smart devices, intelligent processing and informative communication has taken the Internet of things (IoT) to a new level....     

(90)Sr, (210)Po and (210)Pb in lichen and reindeer in Norway

Concentrations of (90)Sr, (210)Po and (210)Pb in lichen and reindeer were studied in central (?stre Namdal) and southern Norway (V?g?) during 2000-2003. The study focussed on potential differences in concentrations of these nuclides in reindeer of different ages. Concentrations of (90)Sr in bones of approximately 10 year old adult females were about 40% higher than those in calves' antlers ((90)Sr concentrations in antlers and bones of calves are similar), while the available data from V?g? suggest that (90)Sr concentrations in reindeer calves decreased with an effective ecological half-time of 9.03+/-0.06 years during 1988-2002. Furthermore, (90)Sr concentrations were 50-80% higher in bone of reindeer of a similar age from V?g? compared to those from ?stre Namdal. Concentrations of (210)Po and (210)Pb in muscle and liver tissues were comparable to those reported for reindeer in other Nordic areas, with no significant difference in (210)Po and (210)Pb concentrations between adults and calves or between reindeer from the two different study areas.     

The temporal variations of (7)Be, (210)Pb and (210)Po in air in England

We have conducted measurements of naturally occurring radionuclides (7)Be, (210)Pb and (210)Po in air at ground level at Chilton, Oxfordshire, England. The sampling and analysis regime for the latter two isotopes has been optimised to minimise uncertainties in measurement due to decay of (210)Po and in-growth of (210)Pb during the sampling and analysis period. Analysis times were reduced by using Cerenkov counting to assay the (210)Bi daughter of (210)Pb. Monthly data collected over a four-year period are presented and discussed. (7)Be activity concentrations appear to peak in spring. (210)Pb activity concentrations also follow a seasonal trend reflecting different (222)Rn emanation rates from soil during winter and summer. Data for (210)Po show no such trend.     

Role of allochthonous carbon in the energy of terrestrial invertebrate communities at different distances from the Black Sea and a freshwater lake (Isotopic Evidence)

Isotopic analysis has become an important tool in the study of lateral links between ecosystems. The isotopic composition of carbon in terrestrial and aquatic primary producers can differ significantly, which provides an opportunity to identify the “marine” or “freshwater” carbon in the tissues of terrestrial animals. We measured the isotopic composition of C and N in tissues of soil invertebrates and estimated the proportion of “aquatic” carbon in the energy budget of terrestrial food webs at different distances from the Black Sea and a freshwater lake. Terrestrial predators are actively subsidized with carbon from the Black Sea to distance of up to about 50 m. The carbon subsidy from the freshwater lake is significant in the zone extending no farther than the forest border (ca. 15 m). Thus, the effect of allochthonous organic matter on terrestrial communities in both cases manifests itself only in a relatively narrow coastal strip.     

Association of organic matter, iron and inorganic phosphorus in lake waters

Gel permeation chromatography was used to fractionate ³²PO₄³⁻ labelled components by molecular size in filtered, destabilized lake foam, concentrated lake water, and lake sediment extracts. Evidence is presented for the abiotic formation of organic matter iron inorganic P complexes in lake foam, water and sediments. ³²PO₄^staggered was found to excahnge with low molecular weight, dissolved P fraction, probably an organic matter -Fe- inorganic P complex, but not with a high molecular weight, non-inorganic dissolved reactive P pool, hypothesized to be similar to the dimer. Our experiments suggest that inorganic P binding by high molecular weight organic matter may play a significant role in the P cycle. If the bound P is unavailable to algae and bacteria, the complexes could explain Rigler's (1968) hypothesis that the molybdenum blue technique may overestimate the free orthophosphate concentration by 10–100 times.     

Transfer of (40)K, (238)U, (210)Pb, and (210)Po from soil to plant in various locations in south of Syria

Transfer factors of (40)K, (238)U, (210)Pb, and (210)Po from soil to some agriculture crops in various locations in south of Syria (Dara'a and Assuwaydaa districts) have been determined. Soil and vegetable crops (green pepper, cucumber, tomato, and eggplant), legumes crops (lentil, chickpea, and broad bean), fruit trees (apple, grape, and olives) and cereals (barley and wheat) were collected and analyzed for (238)U, (210)Pb, and (210)Po. The results have shown that higher transfer factors (calculated as Bqkg(-1) dry wt. plant material per Bqkg(-1) dry wt. soil) for (210)Po, (210)Pb and (238)U were observed in vegetable leaves than fruits and cereals leaves; the highest values of transfer factor (TF) for (238)U were found to be 0.1 for straw of chickpea. Transfer factors for (210)Po varied between 2.8x10(-2) and 2 in fruits of eggplant and grain of barley, respectively. In addition, several parameters affecting transfer factors of the radionuclides were evaluated. The results can be considered as base values for TF of natural radionuclides in the region.