Laboratory study of impacts of concrete fragment sizes on wetland water chemistry

This study investigated the effects of urban concrete materials, of different particle sizes, immersed in water through a laboratory-based experiment. Water was sourced from a high conservation-value wetland (Blue Mountains upland swamp). Prior to the experiment, wetland water was dilute (32.5 μS/cm), acidic (pH 5.3) and had detectable major ion concentrations of only sodium and chloride. Water was exposed to three treatments of different concrete fragment sizes (whole, crushed and fine). All treatments increased conductivity and pH and also resulted in modified ionic composition where calcium, potassium, hydroxide, carbonate and sulphate were recorded at much high levels. The extent and speed of water chemistry changes was linked to the particle size of the concrete. The results of this study support the hypothesis that concrete can be an environmentally hazardous material influencing water quality in urban catchments.     

Legislation and the motor car

Vehicle legislation for safety and emission control is led by the USA where half the world's cars and one‐third of the world's road deaths are found. The 1975/6 standards will cause confrontations between industry and government in the U.S.A. and have costly implications for the American people. The rest of the world is affected by what happens in the U.S.A. but for language and other reasons fragmented laws are normal with conflicting requirements for manufacturers who supply the many markets. The greatest force for harmonization of legislation may be the enlarged Common Market including, as it does, the four major European Car manufacturing countries. The Common Market Commission may displace WP 29 of the United Nations as the leading law‐making body. Type approval is the compliance system used in Europe, but the growth in scope of safety and other legislation is bringing into focus a weakness of the system which is reducing production efficiency to an alarming degree. American style self‐certification is not acceptable to European governments.     

Effect of dietary and synthetic chelating agents on the intestinal absorption of lead

The effect of a number of dietary and synthetic chelating agents on the intestinal absorption of lead has been examined using the everted sac preparation and the tracer isotope ²⁰³Pb. All the agents examined increased lead transport into the serosal compartment. An explanation of the way in which these agents modify the model to describe lead transport is proposed.     

The use of site surveys in the collection of recreation data,with particular Reference to the congleton district of Cheshire

The provision of countryside recreation facilities at a local level is likely to receive increasing attention during the next decade. As an integral part of the assessment of the quality of present provision within the Congleton District of Cheshire (U.K.) five site surveys were made. Each site provides different facilities for recreation and interview questions were designed to investigate the background of the visitors and the nature of the interplay between site and visitor. The analysis of answers attempts to illustrate those aspects of this interrelationship, which may be important during the consideration of future provision of recreation sites and their management.     

Changes in zooplankton populations in the White Volta with particular reference to the effect of Abate

The 24‐hour LC 50 of the nauplii of Thermocyclops hyalinus using Abate CE 200 solution was 0.23 ppm., while the 24‐hour LC 50 of both the copepodite and adult stages was 0.2 ppm.

The numbers of drifting zooplanktonic Microcrustacea in the White Volta increased in numbers during the months of March, April, May, June and July in the dry season. The increase in numbers in the post‐sunset samples related to the vertical migration of the zoqplankton in the reservoir upstream. The aerial weekly application of Abate CE 200 solutions at very high lethal concentrations did not seem to affect the Microcrustacea population probably because (a) Microcrustacea drifting into the reservoir from upstream sustained populations in the reservoir; (b) Microcrustacea living at the banks of the reservoir escaped the abate effect flowing downstream; and (c) spraying was done around noon, when the majority of the zooplankton population had migrated to the bottom of the reservoir.