Calcium-Lead Interactions Involving Earthworms: An Hypothesis

This paper surveys the published literature on Ca-Pb interactions involving earthworms, and attempts to rationalize the information within a simple hypothetical scheme. The scheme recognises that Ca-Pb interactions operate within at least 3 major 'compartments': the geochemical or soil compartment; a metabolic or transport compartment; and in the cumulative or detoxification (chloragosome) compartment. The scheme also recognises that the consequences of Ca-Pb interactions differ under acidic and calcareous soil conditions. Finally, attention is drawn to those biotic and abiotic areas that require further study if earthworms are to be considered seriously for pollution monitoring purposes.     

PERIVITELLINE pH OF SALMONIDE EGGS IN RELATION TO AMBIENT pH1

ABSTRACT: Eggs from salmon and brown trout were reared at 6 pH levels in the pH range 4.1–7.5. By micropuncture, the pH of the perivitelline fluid (PVF) was measured at different stages of development with an antimony microelectrode system. The pH of the PVF falls with decreased pH of the ambient media, although no point of equilibrium was found at the lower pH levels. When eggs were reared at pH levels 4.1–4.7, the pH of the PVF in salmon eggs was 0.4 units above the ambient media, while that in trout eggs was 1.0 pH units above. Decreased pH of the PVF during the later, actively ion accumulation, embryonic stages will subject the embryos to ion regulating stresses similar to those registered for adult fishes.     

Progress with Implementing the Environmental Assessment Requirements of the Resource Management Act in New Zealand

The Resource Management Act 1991 (RMA) has introduced environmental impact assessment (EIA) into the operations of territorial authorities at the regional and district level in New Zealand. The system established by the RMA is not only devolved in administrative terms, it is also comprehensive in its application. This paper reports the findings of an interview-based survey of key personnel in selected regional and district councils, along with others from government departments, planning consultancies and law firms. The purpose is to assess the success of the councils in developing appropriate and workable procedures, and to identify the main problems likely to inhibit the development of an effective EIA system in New Zealand. Overall, the task of implementing the EIA requirements has been tackled positively by councils, but there are signs of major differences emerging in the EIA procedures they are developing. Key issues that need to be considered by councils include: the need for explanatory documentation for, and verbal advice to, resource consents applicants at the earliest stage possible; the lack of public involvement in the EIA activities and the need for council staff to encourage and facilitate such participation; and problems with ensuring the adequacy of EIA information in such a devolved and comprehensive EIA system.     

WATER CONSERVATION KITS: A TIME SERIES ANALYSIS OF A CONSERVATION POLICY1

ABSTRACT: The effect on water usage of installing water conservation kits in the city of Oxnard, California, is statistically evaluated. Using binary multiple regression analysis on a large sample of residential units, water consumption was compared before and after receipt of the kit. For this sample, installers reduced water consumption by 4.2 percent each billing period. Income (wealth) and household size elasticities are reported along with the Characteristics of the installing households.