Removal of dyes from an artificial textile dye effluent by two agricultural waste residues,corncob and barley husk

The use of a previously untried biosorbent, barley husk, for dye removal is compared to corncob. The effectiveness of adsorption as a means of dye removal has made it an ideal alternative to other more costly treatments. This paper deals with two low-cost, renewable biosorbents, which are agroindustrial by-products, for textile dye removal. Experiments at total dye concentrations of 10, 20, 30, 40, 50, 100, 150, and 200 mg l(-1) were carried out with an artificial effluent consisting of an equal mixture of five textile dyes. The effects of initial dye concentration, biosorbent particle size, dose of biosorbent, effective adsorbance, and dye removal kinetics were examined. One gram (per 100 ml) of < or = 600 microm corncob was found to be effective in removing a high percentage of dyes at a rapid rate (92% in 48 h). One gram of I x 4 mm barley husk was found to be the most effective weight and particle size combination for the removal of dyes (92% in 48 h). The results illustrate how barley husk and corncob are effective biosorbents concerning the removal of textile dyes from effluent.     

Public registers of environmental information: an assessment of their role

Considerable importance is attached to the role of the public in environmental matters as consumers, investors, lobbyists and electors. To involve the public in safeguarding the environment it is necessary to capture their interest and to inform them. This paper assesses the contribution of registers of environmental information as one way of informing the public. It draws together the findings of three separate pieces of research into the use of public registers (including water registers, planning registers, local air pollution control registers and waste registers) undertaken in the last seven years. The registers are assessed in terms of their contribution in promoting public reassurance, agency accountability, industrial responsibility and public participation.     

Reviewing University Community Gardens for Sustainability: taking stock,comparisons with urban community gardens and mapping research opportunities

Community gardens (CGs) in university settings are faced with challenges associated with a transient and inexperienced population of student gardeners, but they also have the potential to have a lasting impact on the food behaviours of many young people. This paper undertakes a systematic critical review of literature about University Community Gardens for Sustainability (UCGS) in order to suggest directions of future research in the emerging field research about CGs within and outside of universities. The literature shows that UCGS have similar benefits to those identified in urban CG literature; but with greater emphasis on both the educational and environmental sustainability benefits, suggesting an under-used potential of CGs in these areas. We argue that a better understanding of the particular challenges and benefits of UCGS could improve outcomes of CGs in all settings. Therefore we recommend that future should explore: (1) participant transience in CGs, thereby helping sustainability projects with large volunteer bases learn to cope with challenges this poses in order to maximise the garden’s impacts; (2) whether/how participating in CGs can contribute to changes in attitudes/behaviours with regards to sustainability and be used as a tool for Education for Sustainability in and outside of university settings and (3) failed cases of CGs to genuinely understand factors that contribute to success. By addressing these areas we can improve our understanding of how community gardening can contribute to our communities, universities and environment, and can begin to make these potential contributions a reality.     

Division of labor between undertaker specialists and other middle-aged workers in honey bee colonies

A primary determinant of colony organization in temporally polyethic insect societies is inter-individual variation in behavior that is independent of worker age. We examined behavioral repertoires, behavioral correlates of adult development, and spatial distributions within the hive to explore the mechanisms that produce behavioral variation among middle-age honey bees (Apis mellifera). Individually labeled undertakers, guards, food storers, and wax workers exhibited a broad range of task-related behavior, but bees tagged as undertakers were more likely to subsequently remove a corpse from the hive and handle a corpse compared to other middle-aged bees. The activity level of undertakers was similar to other task groups, suggesting that undertaking specialists were neither hyper-active “elites” nor quiescent “reserves” that become active only when a dead bee stimulus is present. Undertakers also were more likely to remove debris and to remain in the lower region of the hive or near the entrance, even when not engaged in corpse removal; both preferences may promote colony efficiency by reducing inter-task travel times. Guards and undertakers were less likely to perform behavior normally associated with young bees compared to food storers and wax workers. Undertakers and guards also initiated foraging at earlier ages than the other task groups. These results suggest that undertakers and guards may be slightly developmentally advanced compared to food storers and wax workers. There also was evidence for lifetime differences in behavioral preferences which could not be explained by differences in adult development. Bees tagged as undertakers were more likely to subsequently remove a dead bee during their entire pre-foraging career compared to other task groups or members of their general age cohort. Differences in both the rate of adult development and individual behavioral preferences, both of which may be subject to genetic and environmental influences, are important determinants of inter-individual variation among honey bees of middle age. Received: 5 February 1997 / Accepted after revision: 27 May 1997     

Sources of atmospheric carbonaceous particulate matter in Pittsburgh,Pennsylvania

The organic carbon (OC)/elemental carbon (EC) tracer method is applied to the Pittsburgh, PA, area to estimate the contribution of secondary organic aerosol (SOA) to the monthly average concentration of organic particulate matter (PM) during 1995. An emissions inventory is constructed for the primary emissions of OC and EC in the area of interest. The ratio of primary emissions of OC to those of EC ranges between 2.4 in the winter months and 1.0 in the summer months. A mass balance model and ambient measurements were used to assess the accuracy of the emissions inventory. It is estimated to be accurate to within 50%. The results from this analysis show a strong monthly dependence of the SOA contribution to the total organic PM concentration, varying from near zero during winter months to as much as 50% of the total OC concentration in the summer.     

Population activity patterns — St. Louis study

In the context of exposure monitoring, activity patterns refer to the manner in which individuals' activities are distributed in time, in space, and by environmental mode. The background and design are given for a cross-sectional survey conducted in the St. Louis area during 1978–1979. Activity pattern estimates from the study, based on a combination of usual frequency and diary methods, are presented and their limitations are discussed. Methods for and the types of estimates from national studies employing time-use diaries are presented. Considerations for activity pattern recording during future monitoring studies are provided.     

Pesticide Contamination of Jamaican Environment. II. Insecticide Residues in the Rivers and Shrimps of Rio Cobre Basin, 1982–1996

Only organochlorine (OC) residues were monitored by gas chromatographyin water, sediment and shrimp samples collected everymonth between July 1982 and August 1983 from therivers of Rio Cobre basin. In samples collected everyfour months during 1989–1990, and seven times duringJuly 1995–March 1996, OC and OP (organophosphates)residues were monitored. Carbamate and pyrethroidresidues were not monitored. The detection ofresidues in 1982–1983 was 54 to 100% in water andsediment, and 83 to 100% in shrimp samples fromvarious sampling stations in the four rivers. In otheryears, it ranged from about 40 to 100% in the threetypes of samples.In 1982–1983, DDE and dieldrin residues were found tobe much higher than those of lindane and - and-endosulfan in Black River, Rio Pedro, ThomasRiver and Rio Cobre in the watershed. The ranges ofmeans of each residue in water (g L^-1), sediment(ng g^-1) and shrimp (ng g^-1) samples, respectively, were:DDE, 0.059–102.0, 3.44–13.97, 0.344–14.57;dieldrin, 0.026–173.6, 1.21–2.75, 0.427–5.59;-endosulfan, bdl, 1.75–4.00, bdl;-endosulfan, bdl (below detectable limits), 2.51–9.48, bdl;and lindane, (bdl), 0.110–0.319, 2.90.In 1989–1990 and 1995–1996, residues of six OCs and two OPs were detected quite regularly. DDE, dieldrinand Chlorpyrifos residues were much higher than thoseof the other insecticides. The range of their meansin water (g L^-1), sediment and shrimp (ng g^-1),respectively, were: DDE, 1.66–19.76, 0.941–5.84,1.11–8.32; dieldrin, 0.077–7.22, 0.425–3.31,0.385–1.59; -endosulfan, 0.034–1.25, 0.021–1.22, 0.032–3.62; -endosulfan, 0.665–1.23,0.008–3.60, 0.005–3.97; endosulfan sulphate, 0.959–1.34, 0.035–3.08, 0.012–1.80; lindane, bdl,0.005–0.82, 1.19–1.56; chlorpyrifos, 0.702–4.06,0.005–1.51, 0.156–7.04; and diazinon, bdl, 0–0.150, 0.001–0.006. At the mouth of the river, whereit discharges into the sea, the levels of almost allthe residues were higher than upstream.     

Weed interference on maize (Zea mays) under no tillage system

A field trial was carried out in Brazil in March 2002 with the aim to evaluate the effects of different timing and extension of weedy period on maize productivity. The hybrid Pioneer 30K75 was sowed under 7 t ha(-1) mulching promoted by glyphosate spraying. The treatments were divided in two groups: In the first group, weeds were maintained since the maize sowing until different periods in the crop cycle: 0, 14, 28, 42, 56, 70, and 150 days (harvesting time). In the second group, the maize crop was kept weed free for the same periods of the first group. Weed control was done through hand hoeing. A complete randomized blocks experimental design with five replications was used for plots distribution in the field. Nonlinear regression model was used to study the effects of weedy or weedfree periods on maize productivity. Weed community included 13 families and 31 species. Asteraceae, Poaceae, and Euphorbiaceae were the most abundant families. Results showed that under no tillage condition with 7 t ha(-1) mulching at sowing time, the maize crop could cohabit with weed community for 54 days without any yield lost. On the other hand, if the crop was kept weed free for 27 days, the weed interference was not enable to reduce maize production. According to these results one weed control measure between 27 and 54 days after crop emergence could be enough to avoid any reduction in maize productivity.