Humification index of composts originating from three types of woody biomass

Composting is a good method for recycling surplus manure and stabilizing organic matter from biowastes. Compost is used as a soil amendment and recently, for restoration of vegetation in barren areas. We investigated the relationship between the type of woody biomass (using Robinia pseudoacacia, Japanese larch and apple) and the humification index (HI) of the resulting compost. This study evaluated the difference in HI between the three compost types, and the structural features of composts and extracted humic acids (HAs). The HIs for R. pseudoacacia and apple were larger than that for Japanese larch after composting for 11 months. The structural features of the Japanese larch compost were also different from the apple and R. pseudoacacia, with a very high carbon/nitrogen ratio. The average molecular weights and ultraviolet–visible spectra (A600/C) of HAs extracted from composting samples at 0 and 11 months indicate that the humification rate of Japanese larch was slower than that of R. pseudoacacia and apple. During composting, the average molecular weights of apple and R. pseudoacacia decreased, while their A600/C values increased, but the reverse was observed for Japanese larch. The humification rate was found to depend on the type of woody biomass being composted.     

Evaluation of entanglement properties of crushed automobile shredded residue and detachment of entrapped particles

Automobile shredded residue is a potential solid fuel when its metal and chlorine-containing parts have been removed. The authors have investigated physical separation of automobile shredded residue to obtain the components that may be used in solid fuel and found that agglomerates of entangling fiber-like components are formed during crushing, making removal of metals and chlorine-containing parts difficult. In this paper, a reattachment ratio, entrapment ratio, and disentanglement ratio are proposed to evaluate the entanglement properties of crushed automobile shredded residue. It is found that products smaller than 16 mm were not reattached easily in the sieving process, and an index based on entanglement properties proposed here is useful to predict suitable crushing conditions. Wet detachment of entrapped particles from agglomerates of entangling materials was also applied to separate particulate matter from crushed ASR.     

Demographic heterogeneity, cohort selection, and population growth

Demographic heterogeneity--variation among individuals in survival and reproduction--is ubiquitous in natural populations. Structured population models address heterogeneity due to age, size, or major developmental stages. However, other important sources of demographic heterogeneity, such as genetic variation, spatial heterogeneity in the environment, maternal effects, and differential exposure to stressors, are often not easily measured and hence are modeled as stochasticity. Recent research has elucidated the role of demographic heterogeneity in changing the magnitude of demographic stochasticity in small populations. Here we demonstrate a previously unrecognized effect: heterogeneous survival in long-lived species can increase the long-term growth rate in populations of any size. We illustrate this result using simple models in which each individual's annual survival rate is independent of age but survival may differ among individuals within a cohort. Similar models, but with nonoverlapping generations, have been extensively studied by demographers, who showed that, because the more "frail" individuals are more likely to die at a young age, the average survival rate of the cohort increases with age. Within ecology and evolution, this phenomenon of "cohort selection" is increasingly appreciated as a confounding factor in studies of senescence. We show that, when placed in a population model with overlapping generations, this heterogeneity also causes the asymptotic population growth rate lambda to increase, relative to a homogeneous population with the same mean survival rate at birth. The increase occurs because, even integrating over all the cohorts in the population, the population becomes increasingly dominated by the more robust individuals. The growth rate increases monotonically with the variance in survival rates, and the effect can be substantial, easily doubling the growth rate of slow-growing populations. Correlations between parent and offspring phenotype change the magnitude of the increase in lambda, but the increase occurs even for negative parent-offspring correlations. The effect of heterogeneity in reproductive rate on lambda is quite different: growth rate increases with reproductive heterogeneity for positive parent-offspring correlation but decreases for negative parent-offspring correlation. These effects of demographic heterogeneity on lambda have important implications for population dynamics, population viability analysis, and evolution.     

Evaluation of the water quality of the Hakata River based on diatoms

We investigated the epilithic diatom assemblage of samples collected from three sites of the Hakata River, Fukuoka, Japan, on November 26, 2008. Each taxon was photographed and identified. The 1747 diatom frustules collected were classified into 33 taxa belonging to 17 genera. Nitzschia fonticola was abundant at all sites. The DAIpo (the diatom assemblage index to organic water pollution) values for sites 1, 2, and 3 were 50.2, 44.1 and 48.0, respectively, indicating that the water quality of the Hakata River was at β-mesosaprobic level.     

Characterization of Activated Carbon Fiber Filters for Pressure Drop,Submicrometer Particulate Collection,and Mercury Capture

ABSTRACT

The use of activated carbon fiber (ACF) filters for the capture of particulate matter and elemental Hg is demonstrated. The pressure drop and particle collection efficiency characteristics of the ACF filters were established at two different face velocities and for two different aerosols: spherical NaCl and combustion-generated silica particles. The clean ACF filter specific resistance was 153 kg m^-2 sec^-1. The experimental specific resistance for cake filtration was 1.6 × 10⁶ sec^-1 and 2.4 × 10⁵ sec^-1 for 0.5- and 1.5-μm mass median diameter particles, respectively. The resistance factor R was approximately 2, similar to that for the high-efficiency particulate air filters. There was a discrepancy in the measured particle collection efficiencies and those predicted by theory. The use of the ACF filter for elemental Hg capture was illustrated, and the breakthrough characteristic was established. The capacity of the ACF filter for Hg capture was similar to other powdered activated carbons.     

Characteristics of slag, fly ash and deposited particles during melting of dewatered sewage sludge in a pilot plant

This study examines slag, fly ash, and deposited particles during melting of dewatered sewage sludge in a pilot plant. In addition, the chemical composition of particles in flue gas was simulated using a thermodynamics program, namely FACTSage 5.2. The results showed that the main components of slag were Al, Fe, Ca, P and Si; the minor components were Na, K, Mg, Cu, and Zn. The main chemical compound of slag was Ca4(Mg,Fe)5(PO4)6. For fly ash particles, heavy metals with the highest concentrations were in the order of Zn and As, Pb, Cu, and Cd, respectively. For non-heavy metals, Al, Fe and P were also found in significant amounts. The majority of deposited particles were composed of elements of Zn, P, S, Na, Fe, Al, Si, and Ca and such chemical compounds as Zn3(PO4)2, AlPO4, FePO4 and Fe(OH)3 while the minority consisted of elements of As, Cu, and Pb. Moreover, the compositions of deposited particles in each chamber differed due to different flue gas temperatures inside. In the secondary chamber at 760 degrees C, the amounts of Fe and Al were higher than Zn, whereas, in the other chambers (600-400 degrees C), the amount of Zn was higher. In other words, at the lower temperature the deposition of Zn was higher than the deposition of Fe and Al. In the water cooling section, volatile elements (i.e. Zn, As, Cu, Pb) were found in the highest concentrations due to a big difference in temperature between the wall surface and flue gas. From the simulation results, most of the elements in the gas phase were found to be chloride compounds, whereas those in the solid phase were in the form of oxide, sulfate, and phosphate compounds.     

Surgical examination of male genital function of calopterygid damselflies (Odonata)

Male genitalia show rapid and divergent evolution. It is rarely determined whether variation in male genital morphology influences male reproductive success. Male damselflies possess a unique aedeagus with a re-curved head and spiny lateral processes, and most females have two sperm storage organs, a spherical bursa copulatrix and a tubular spermatheca. Previous studies have indicated that the re-curved head may remove bursal sperm, whereas the lateral processes remove spermathecal sperm. However, we need more direct evidence of these functions. We compared sperm number in female sperm storage organs by interrupting copulation to examine sperm removal by the male. In Calopteryx cornelia, males removed almost all bursal sperm but only partially removed spermathecal sperm. In contrast, females of Mnais pruinosa store sperm primarily in the bursa, and males removed only bursal sperm. To examine the functions of male spiny lateral processes, we compared mating behaviour between control and experimental males from which we removed (cut) the lateral processes. In C. cornelia, cutting of the lateral processes resulted in a decreased number of abdominal movements during copulation and no removal of spermathecal sperm. The amount of bursal sperm removed during copulation also decreased in experimental males compared to the unmanipulated males. However, in M. pruinosa, the experimental removal of male lateral processes did not decrease the abdominal movements and little affected the removal of bursal sperm. Inter-specific differences between C. cornelia and M. pruinosa may be caused by variation in the strategies of female sperm storage.     

Aniline removal by Photocatalytic reaction of iron(iii) mediated with dissolved organic matter

When light (> 370 nm) was allowed to interact with an aqueous solution containing dissolved organic matter (DOM) and Fe(III), removal of aniline (AN) was observed. This was due to the photocatalytic reaction of Fe(III) mediated by DOM. Syringic acid (SYA) and humic acid (HA) were used as DOM in the present study. The ¹⁵N‐NMR spectrum of the product mixture from the light irradiation of the SYA/Fe(III) system demonstrated that AN was covalently bound to SYA. The kinetics of AN removal were, therefore, interpreted by assuming covalent binding between DOM and AN. The amounts of covalent binding sites and the apparent second‐order rate constants could be evaluated, and the amounts of covalent binding sites decreased with the increases of the concentration of DOM. This is attributed that the polymerization of DOM by the photo‐oxidation competed with the covalent binding between AN and DOM.     

Effect of tributyltin on veliger larvae of the Manila clam, Ruditapes philippinarum

We investigated the effects of waterborne and maternal exposure to tributyltin (TBT) on veliger larvae of the Manila clam, Ruditapes philippinarum. In a waterborne exposure test, veliger larvae (D-larvae stage: 24h after fertilization) were exposed to TBT at measured concentrations of <0.01 (control), 0.055, 0.130, 0.340, and 0.600microg/l for 13d. The percentage of normal veliger larvae (the ratio of normal veliger larvae to all larvae) decreased significantly in all TBT treatment groups compared with that in the control group. In a maternal exposure test, 100 clams were exposed to TBT at measured concentrations of <0.01 (control), 0.061, and 0.310microg/l at 20-22 degrees C for 3 weeks, and the percentage of normal veliger larvae assessed for 13d. No maternal effects on veliger larvae from TBT were observed in TBT treatment groups as compared with the control group. These results demonstrate that waterborne TBT affects Manila clam veliger larvae, and indicates that TBT may have reduced Manila clam populations by preventing the development and survival of veliger larvae.