Impacts of Climatic Change On Peatland Hydrochemistry; A Laboratory-Based Experiment

A laboratory simulation of a reduction in water table height that could be anticipated from current climate change models, resulted in a change in the efficiency with which a valley-bottom wetland acted as a sink/source of nutrients. Effects were confined to the upper 10 cm of the profile, but since this depth has the greatest hydraulic conductivity, it was noted that the effects of hydrochemical changes therein would be readily transferred to receiving waterbodies. Marked changes in leachate chemistry were observed, including increases in nitrate and sulphate concentrations, while concentrations of phenolics, dissolved organic carbon, potassium, iron and ammonium decreased. These changes have implications for the quality and productivity of waters draining wetlands.     

Parental investment and its ecological consequences in the solitary wasp Sceliphron assimile (Dahlbom) (Sphecidae)

Summary The sphecid wasp Sceliphron assimile Dahlbom builds mud cells whose volumes are positively correlated to maternal length, the relationship being highly significant for daughters (Fig. 1). However, small females build cells longer and wider in relation to their own body length than large females do (Fig. 3). Cell volume closely regulates the total weight of prey stocked per cell (Figs. 4, 10). Maternal length is directly related to prey size and inversely related to the number of prey stocked (Fig. 5). Female length, above a threshold of 19 mm, probably does not influence her chance of starting a nest (Fig. 6) but is strongly positively correlated to achieved fecundity. Large females have larger offspring and a higher proportion of daughters than small females do (Fig. 7), but this is largely controlled by maternal behaviour rather than by genetical mechanisms (Fig. 10). The results are in general agreement with those of Trivers and Hare (1976) for solitary wasps, but large progeny are cheaper to produce per unit weight than small ones, and for a given weight sons are cheaper to produce than daughters.     

Analysis of air quality in Dire Dawa,Ethiopia

Ambient air quality was monitored and analyzed to develop air quality index and its implications for livability and climate change in Dire Dawa, Ethiopia. Using survey research design, 16 georeferenced locations, representing different land uses, were randomly selected and assessed for sulfur dioxide (SO₂), nitrogen dioxide (NO₂), carbon dioxide (CO₂), carbon monoxide (CO),volatile organic compounds (VOCs), and meteorological parameters (temperature and relative humidity). The study found mean concentrations across all land uses for SO₂ of 0.37 ± 0.08 ppm, NO₂ of 0.13 ± 0.17 ppm, CO₂ of 465.65 ± 28.63 ppm, CO of 3.35 ± 2.04 ppm, and VOCs of 1850.67 ± 402 ppm. An air quality index indicated that ambient air quality for SO₂ was very poor, NO₂ ranged from moderate to very poor, whereas CO rating was moderate. Significant positive correlations existed between temperature and NO₂, CO₂, and CO and between humidity and VOCs. Significant relationships were also recorded between CO₂ and NO₂ and between CO and CO₂. Poor urban planning, inadequate pollution control measure, and weak capacity to monitor air quality have implications for energy usage, air quality, and local meteorological parameters, with subsequent feedback into global climate change. Implementation of programs to monitor and control emissions in order to reduce air pollution will provide health, economic, and environmental benefits to the city.

Implications: The need to develop and implement emission control programs to reduce air pollution in Dire Dawa City is urgent. This will provide enormous economic, health, and environmental benefits. It is expected that economic effects of air quality improvement will offset the expenditures for pollution control. Also, strategies that focus on air quality and climate change present a unique opportunity to engage different stakeholders in providing inclusive and sustainable development agenda for Dire Dawa.     

The Atmospheric Dust Problem

This article concerns the control of emissions from a local dolomite plant through a series of corrective measures. With a new State regulation on particulate emissions (process weight table) passed in 1965, and with a new local control program, a goal was established toward which control measures were directed. Inplant investigations revealed that measures would be necessary to eliminate emissions from the pulverizer and conveyor belts. In order to meet State requirements, a better method of collection for the dryer was required. In order to evaluate the effect of these changes on the ambient air, dustfall jars and high-volume air samplers were used and stack sampling was conducted at and around the local dolomite plant and also at another such plant in Venice, Fla. Through successive control and testing, emission factors for dolomite plants, as well as reduction of plant emissions and resident complaints, were established.     

Particle Size Distribution of Settled Dust

In 1958, San Bernardino County Air Pollution Control District adopted rules and regulations for the control of dust, fumes and particulate matter. These were taken from ordinances which had been effectively used in other areas. After three years, experience showed that in some instances these rules and regulations should be modified to take into consideration the specific industrial operations in the county. A technical committee was appointed to examine this problem and concluded that a reasonable rule would be one that protects the public from the undesirable effects of dusts, fumes and particulate matter but would not impose an unnecessary burden on industry. Dustfall samples were collected at various locations throughout San Bernardino County and examined for particle-size distribution. In order to obtain reliable data, fairly large samples had to be collected in a short time. A 12 foot square plastic sheet was found suitable for sample collection. Particle size determinations were made with both the coulter counter and the Bahco microparticle classifier. The two methods yielded comparable results. It was found that settled dust particles for all practical considerations were all greater than 30 microns in equivalent diameter. Regulations based on these findings are being developed.     

Industrial Pollution Prevention! A Critical Review

Abstract

Pyrolytic product distribution rates and pyrolysis behavior of tire-derived fuels (TDF) were investigated using thermogravimetric analyzer (TGA) techniques. A TGA was designed and built to investigate the behavior and products of pyrolysis of typical TDF specimens. The fundamental knowledge of TGA analysis and principal fuel analysis are applied in this study. Thermogravimetry of the degradation temperature of the TDF confirms the overall decomposition rate of the volatile products during the depolymerization reaction. The principal fuel analysis (proximate and ultimate analysis) of the pyrolytic char products show the correlation of volatilization into the gas and liquid phases and the existence of fixed carbon and other compounds that remain as a solid char. The kinetic parameters were calculated using least square with minimizing sum of error square technique. The results show that the average kinetic parameters of TDF are the activation energy, E = 1322 ± 244 kJ/mol, a pre-exponential constant of A = 2.06 ± 3.47 × 10¹⁰ min^?1, and a reaction order n = 1.62 ± 0.31. The model-predicted rate equations agree with the experimental data. The overall TDF weight conversion represents the carbon weight conversion in the sample.