Quantifying nutrient inputs by gulls to a fluctuating lake,aided by movement ecology methods

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Selenium Impacts on Fish: An Insidious Time Bomb

A selenium time bomb situation is developing in the United States and elsewhere that may result in substantial impacts on fish populations. The selenium time bomb has three components: (1) high food-chain bioaccumulation, (2) steep toxic response curve for fish, and (3) insidious mode of toxicity. If the threshold for selenium toxicity is exceeded, the time bomb explodes and a cascade of events is set into motion that will result in major ecosystem disruption. Several human-related factors are emerging that are capable of igniting the fuse of the time bomb by increasing waterborne concentrations of selenium and providing conditions favorable for bioaccumulation. Some of these factors are (1) mobilization of selenium due to open-pit phosphate mining, (2) use of constructed wetlands to treat selenium-laden wastewater from oil refineries and agricultural irrigation, (3) landfill disposal of seleniferous fly ash from coal-fired power plants, and (4) mobilization of selenium from animal feedlot wastes. Collectively, these threats may be sufficient to cause widespread, unanticipated toxic effects in fish populations. Only environmentally sound risk assessments followed by prudent management actions can defuse the selenium time bomb — once it explodes, it is too late to avoid significant impacts.     

Review: Anaerobic treatment of municipal sanitary landfill leachates: the problem of refractory and toxic components

The wide use of municipal sanitary landfills has drawn attention to the leaching effluent generated, this may be problematic to the site's environment, whether by infiltration or other contaminating modes. Anaerobic digestion has been shown to be one of the most efficient systems with which to treat this type of effluent. This article reviews the techniques used by different authors for leachate characterization, specifically related to refractory and toxic components and their effect on anaerobic treatability. In addition, it covers the treatment of refractory organics, organic and inorganic toxic materials and the nutrient balance for adequate system operation. The main conclusions are that there is ample availability of methods by which to identify the different components present in leachates as well as for their toxicity assessment and that nutrients are in general available in sufficient amounts. Treatability studies are presented which are shown to be of general value and can be used in a straightforward manner.     

Settlement Prediction for Municipal Solid Waste Landfills Using Power Creep Law

One of the most important factors that affect the post-closure operation of a landfill is the settlement of refuse and foundation material. Prediction of settlement of refuse is complex because of the mechanisms of settlement and the heterogeneity of the refuse. The settlement of a landfill can be estimated using a simplified method, the Power Creep Law. Based on the analysis of published data measured in the field from four landfills, a correlation is proposed between two parameters, reference compressibility and rate of compression, required to predict the refuse settlement using the Power Creep Law. The settlement-time relationships of waste landfills predicted using the proposed correlation show better agreement with the measured settlements than the settlements predicted using average values or some arbitrary combination of the parameters.     

Synthesis of Chalcones,Flavanones Isolated from Popowia cauliflora and Their Analogues

Rabbit antibody to reduced carboxymethylated bovine β-lactoglobulin (SCM-β-Lg) was prepared and characterized in order to study the antigenic property of bovine β-lactoglobulin (β-Lg) which is a potential cause of an allergy to cow’s milk.

On immunodiffusion analysis, a clear, single precipitin arc was produced between SCM-β-Lg and its antiserum, while a barely discernible line was observed between β-Lg and anti SCM-β-Lg antiserum. Analysis of the quantitative precipitation of SCM-β-Lg with β-Lg-absorbed antiserum to SCM-β-Lg indicated that there were at least four antigenic sites on SCM-β-Lg.

In a quantitative precipitin inhibition test and a two-step inhibition test involving an enzyme- linked immunosorbent assay, anti SCM-β-Lg antibody reacted with peptides 1 ~ 65, 25 ~ 61, 25 ~ 107, 41 ~ 107, 62 ~ 107, 108 ~ 145, 125 ~ 145 and 146 ~ 162 from β-Lg, whereas peptides located in the TV-terminal region, i.e., 1 ~ 7, 8 ~ 24 and 25 ~ 40, and peptide 108 ~ 124 showed little or no measurable affinity for antibody to SCM-β-Lg.

These results indicate that SCM-β-Lg has at least four antigenic sites, which are associated with regions 41 ~ 61, 62 ~ 107, 125 ~ 145 and 146 ~ 162 in the primary structure of β-Lg.     

Product specific emissions from municipal solid waste landfills

This paper presents and verifies the computer tool LCA-LAND for estimation of emissions from specific waste products disposed in municipal solid waste landfills in European countries for use in the inventory analysis of LCA. Examples of input data (e.g. distribution of the waste product in different countries, composition of the product and physical/chemical/biological properties of waste product components) and output data (e.g. estimated emissions to atmosphere and water) are given for a fictive waste product made of representative types of components (toluene, cellulose, polyvinylchloride (PVC), copper and chloride). Since waste products from different processes in the product system may be disposed at different landfills where they are mixed with waste originating outside the product system, the estimated emissions from specific waste products cannot be compared with measured emissions from true landfills. Hence, the computer tool is verified in terms of mass balances and sensitivity analyses. The mass balances agree exactly and the sensitivity analyses show that different types of waste product components behave differently in different types of landfills. Emission of e.g. toluene is significantly reduced in the presence of landfill top-cover, landfill gas combustion units and leachate treatment units. Generally, the sensitivity analysis shows good agreement between the relative proportions of various types of emissions (based on properties of the waste and properties of landfills) and good agreement with emission levels that would be expected based on a general understanding of landfill processes.     

Isolation and identification of mycobacteria from soils at an illegal dumping site and landfills in Japan

In order to study the diversity and community of genus Mycobacterium in polluted soils, we tried to isolate mycobacteria from 11 soil samples collected from an illegal dumping site and 3 landfills in Japan. Using culture methods with or without Acanthamoeba culbertsoni, a total of 19 isolates of mycobacteria were obtained from 5 soil samples and 3 of them were isolated only by the co-culture method with the amoeba. Conventional biochemical tests and sequencing of the hsp65, rpoB, and 16S rRNA genes were performed for species identification of 17 of the 19 isolates. Among the 17 isolates, there was one isolate each of Mycobacterium vanbaalenii, Mycobacterium mageritense, Mycobacterium frederiksbergense, M. vanbaalenii or Mycobacterium austroafricanum, and Mycobacterium chubuense or Mycobacterium chlorophenolicum. The remaining 12 isolates could not be precisely identified at the species level. A phylogenic tree based on the hsp65 sequences indicated that 2 of the 12 isolates were novel species. In addition, 4 isolates were phylogenically close to species that degrade polycyclic aromatic hydrocarbons, which induce some cancers in humans. These results demonstrated that there were many hitherto-unreported mycobacteria in the polluted soils, and suggested that some mycobacteria might play roles in the natural attenuation and engineered bioremediation of contaminated sites with other microorganisms.     

Exploratory Data Analysis of the Multilevel Anthropogenic Zinc Cycle

A comprehensive multilevel contemporary cycle for stocks and flows of zinc is analyzed by the tools of exploratory data analysis. The analysis is performed at three discrete organizational levels—country (53 countries and 1 country group that together comprise essentially all anthropogenic stocks and flows of zinc), world region (9 world regions), and the planet as a whole. The results demonstrate the following: (1) Exploratory data analysis provides valuable and otherwise unobtainable information about material flows, especially those across multiple spatial levels. (2) All distributions of countrylevel zinc stock and flow data are highly skewed, a few countries having large magnitudes, many having small magnitudes. Rates of fabrication of zinc-containing products for the countries are poorly correlated with rates of extraction, reflecting the fact that many countries that extract zinc do not fabricate products from zinc to any significant degree, and vice versa. (4) Virtually all countries are adding zinc to stock in the use phase (in galvanizing applications, zinc castings, etc.). These rates of addition are highly correlated with rates of zinc entering use in all regions, and are higher in regions under vigorous development. (5) With weak confidence, the rate of zinc landfilling by countries appears to be highly correlated with the rate of discard. (6) The statistical distributions of regional-level zinc cycle parameters are approximately log normal. (7) The extremes of normalized statistical distributions of zinc flow values are broader at lower spatial levels (country versus region, for example), but regional interquartile ranges for zinc entering use and zinc discards are higher at regional level then at country level.     

Soil seed bank of the waste landfills in South Korea

The restoration of urban landfill is a topic of growing interest in reclamation ecology as the acreage of abandoned sites near cities increases. The goals of this study were to assess the ecological status of waste landfills and to elucidate the role of seed banks in the establishment of vegetation at these sites. The study sites were located at five landfills around Seoul and Kyongki Province. On average, soils were sampled on 20 plots per landfill in 2001 to record species composition and to estimate the number of seeds in the soil. Soil seed bank vegetation and the individual number of seedlings that germinated were recorded using the seedling emergence method. Relative density per species was calculated from the number of individual seedlings. We conducted canonical correspondence analysis (CCA) using the program CANOCO to survey the relationships between 23 environmental variables and plant importance values. Environmental variables included categorical and numerical variables (landfill age, landfill size, distance from landfill edge, human disturbance level, slope, periodic management level) and soil physico-chemical variables (bulk density, soil moisture content, organic matter content, total N, available P, K, Na, Ca, Mg, Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn). The mean seedling density per m ² differed significantly among sites (P < 0.05). As landfill age increased, the mean seedling density per m ² decreased. The mean seedling density of the Sangpaedong landfill, which was less than 1 year old, was higher than that found in 6- and 7-year-old landfills. The Sangpaedong landfill mainly contained seeds of Chenopodium albumL. and Digitaria ciliaris(L.) SCOP. With regard to early vegetative colonization in landfills, our results highlighted the importance of seed banks occurring in cover soils. Cover soils, derived from various sources, will determine landfill landscapes because of different seed banks present in them. The first axis of the CCA was correlated with landfill age, Na, and human disturbance level, while the second axis was correlated with landfill size, slope, periodic management level, Zn, total N, and organic matter content. Understanding seed banks in landfill cover soils is important, therefore, for proper landfill management and restoration.     

Resource and Climate Implications of Landfill Mining

This study analyzes the amount of material deposited in Swedish municipal solid waste landfills, how much is extractable and recyclable, and what the resource and climate implications are if landfill mining coupled with resource recovery were to be implemented in Sweden. The analysis is based on two scenarios with different conventional separation technologies, one scenario using a mobile separation plant and the other using a more advanced stationary separation plant. Further, the approach uses Monte Carlo simulation to address the uncertainties attached to each of the different processes in the scenarios. Results show that Sweden's several thousand municipal landfills contain more than 350 million tonnes (t) of material. If landfill mining combined with resource recovery is implemented using a contemporary stationary separation plant, it would be possible to extract about 7 million t of ferrous metals and 2 million t of nonferrous metals, enough to meet the demand of Swedish industry for ferrous and nonferrous metals for three and eight years, respectively. This study further shows that landfill mining could potentially lead to the equivalent of a one‐time reduction of about 50 million t of greenhouse gas emissions (carbon‐dioxide equivalents), corresponding to 75% of Sweden's annual emissions.