Observations on the reproduction and postlarval morphology of pourtalesiid sea urchins in the Rockall Trough area (N.E. Atlantic Ocean)

Gametogenesis was studied histologically in the deep-sea species Pourtalesia jeffreysi (Wyville Thomson), P. miranda (A. Agassiz) and Echinosigra phiale (Wyville Thomson) collected during 1973–1983 from various positions at depths of 1 040 to 2 921 m in the Rockall Trough. The gonads are small and no synchrony in terms of the stage of gametogenic development was evident in females of the latter two species collected at different times of the year, indicating nonseasonal breeding. Males appear to be ripe at all times of the year. Follicle cells were well developed around the developing oocytes. Both the size range of the yolky ripe eggs (173 to 357 m diam) and potential fecundity within the range of 1 000 to 4 000 oocytes per individual, are indicative of an abbreviated, indirect, lecithotrophic mode of development occurring in all three species. Pourtalesiid postlarvae occurred also in fine-meshed trawl hauls, and their morphology is described. It was not possible to distinguish between P. miranda and E. phiale at sizes <3 mm in length.     

Phosphorus metabolism and water uptake during final maturation of ovaries of teleosts with pelagic and demersal eggs

An earlier study showed large changes in ovarian phosphoprotein, a characteristic component of vertebrate yolk, during post-vitellogenic meiotic maturation (ripening) of ovaries of teleosts with pelagic eggs. Here, the study of four phosphorus-containing ovarian fractions is extended to other teleost families with pelagic eggs and to species with demersal eggs. Fishes were caught in the sea and lakes of western Scotland between 1982 and 1984. In the codGadus morhua, spratSprattus sprattus, dragonetCallionymus lyra, Norway poutTrisopterus esmarkii, saithePollachius virens, lingMolva molva and flounderPlatichthys flesus, all of which spawn pelagic eggs, the massive water influx during ripening which renders the eggs buoyant was accompanied by large changes in yolk phosphoprotein which were apparent as decrease or disappearance of protein phosphorus as conventionally determined. During ripening of the demersal eggs of the herringClupea harengus, both the water uptake and the decrease in protein phosphorus were less pronounced. In the three-spined sticklebackGasterosteus aculeatus, sea sticklebackSpinachia spinachia, sand gobyPomatoschistus minutus and perchPerca fluviatilis, little or no changes in water content or protein phosphorus both usually increased in species with pronounced water uptake and decreased in species with little or no water uptake. Lipid phosphorus showed little change in all species examined except herring, in which it increased. It is concluded that the characteristic changes in phosphoprotein and other phosphorus-containing fractions are most pronounced in species with pelagic eggs exhibiting massive water uptake on ripening, but are found to a lesser extent in species with demersal eggs in which considerable water uptake accompanies ripening.     

Stem growth reduction in mature Sitka spruce trees exposed to acid mist

An eighteen-year-old clone of Sitka spruce (Picea sitchensis (Bong.) Carr) growing in the field was used to evaluate the whole tree response of 'mature' Sitka spruce to acid mist treatment. The mist, an equimolar mixture of H(2)SO(4) and NH(4)NO(3) at pH 2.5 with or without particles (soda glass ballotini < 20 microm diameter), was applied twice weekly (equivalent to 4 mm precipitation week(-1)) throughout the growing season, May-November 1990-1992. The annual dose of S, N, H applied as mist (at 51, 48 and 3.3 kg ha(-1), respectively) was 2.5 times that measured in the Scottish uplands. Throughout the experiment there was no evidence of visible injury symptoms, yet there was a highly significant reduction (p < 0.02) in the stem-area increment relative to the stem area at the start, measured using vernier dendrometer bands. There was no significant difference between the (acid mist + particle) and the acid mist only treatments. The mean relative stem-area increment over two complete growing seasons (1991-1992) was 65% for control trees, but only 53% for acid-misted trees.     

Effect of cell physicochemical characteristics and motility on bacterial transport in groundwater

The influence of physicochemical characteristics and motility on bacterial transport in groundwater were examined in flow-through columns. Four strains of bacteria isolated from a crystalline rock groundwater system were investigated, with carboxylate-modified and amidine-modified latex microspheres and bromide as reference tracers. The bacterial isolates included a gram-positive rod (ML1), a gram-negative motile rod (ML2), a nonmotile mutant of ML2 (ML2m), and a gram-positive coccoid (ML3). Experiments were repeated at two flow velocities, in a glass column packed with glass beads, and in another packed with iron-oxyhydroxide coated glass beads. Bacteria breakthrough curves were interpreted using a transport equation that incorporates a sorption model from microscopic observation of bacterial deposition in flow-cell experiments. The model predicts that bacterial desorption rate will decrease exponentially with the amount of time the cell is attached to the solid surface. Desorption kinetics appeared to influence transport at the lower flow rate, but were not discernable at the higher flow rate. Iron-oxyhydroxide coatings had a lower-than-expected effect on bacterial breakthrough and no effect on the microsphere recovery in the column experiments. Cell wall type and shape also had minor effects on breakthrough. Motility tended to increase the adsorption rate, and decrease the desorption rate. The transport model predicts that at field scale, desorption rate kinetics may be important to the prediction of bacteria transport rates.     

Wetland protection as land-use planning: The impact of section 404 in Wisconsin,USA

The ability of Section 404 of the Clean Water Act to act as an effective, efficient, and equitable land-use planning tool was assessed through a survey of Section 404 permits in Wisconsin. In a six-month period of permitting, the 404 program reduced wetland losses in the state by 15%. Several factors were examined that may affect permit decisions; these factors are water dependency, alternatives, project type, wetland type, and public or agency comments. Only the water dependency of the project had a statistically significant effect on permit decisions, although development projects that were perceived to provide public good were more likely to be permitted. Environmental impacts of a proposed fill project were not adequately assessed in any of the permit decisions. Because of the way Section 404 is interpreted and administered by the US Army Corps of Engineers, increasing net benefits and achieving an equitable distribution of those benefits is difficult. The corps does not perform any functional evaluations of wetlands nor do they attempt to measure economic value and environmental impacts. In addition, the 404 review process is, in effect, inaccessible to the public. The de facto interpretations of the Section 404 regulations and a lack of program funding and trained personnel all contribute to the program's ineffectiveness.     

Monitoring and enforcement for management of industrial wastes: case study for Thailand

Summary This paper seeks to set the appropriate standards for monitoring and enforcement for the management of industrial wastes and effluents in developing countries. It applies these environmental protection measures to the proposed Samutprakam Province improvement programme in Thailand.Dr Harvey F. Ludwig is a regular contributor toThe Environmentalist (see, for instance, Ludwig, 1990; Ludwig and Browder, 1992). He is Chairman of Seatec International Consulting Engineers where Sow Kim Leng is a consulting engineer. Wanida Srichai is based at the World Environment Center, Thailand Office, Bangkok, Thailand.     

Ozone depletion

Conclusion Not only was the conference well planned and informative, the organisation was excellent. All concerned are to be congratulated. One criticism could be raised. Clearly scientists with first-hand research results are in great demand for ozone- centred meetings. A number at this conference seemed only to have one highly technical paper which they gave regardless of the audience. I say that to be charitable. Surely, none of those I have in mind actually thought they had tailor-made a paper for this heterogeneous audience?The conference was sponsored by the Consumers' Association, Friends of the Earth and the European Campaign Against Cancer. The Chairman was Lord Zuckerman, and the Conference Organiser was Dr Robin Russell Jones.     

Electronic tracking and management of industrial waste in Taiwan

This study discusses an online reporting system used for waste flow tracking (auditing) and investigation of violations. In contrast to systems used in other countries, this system requires waste generators and transporters, as well as the treatment, storage, and disposal facilities (TSDFs) to file online reports on the movement of industrial waste within 24 h of being shipped, received, or completely treated. This system also provides online analytical processing for reporters to analyze all their data, thereby encouraging self-management of waste. Currently there are 25,861 generators, 4,963 transporters, and 865 TSDFs in Taiwan that are required to file online reports. Approximately 80 % of all waste generated in Taiwan is reported using this system. More than 7,000 vehicles are equipped with a global positioning system (GPS) for waste tracking, among which over 2,000 transport hazardous waste. Disposal vehicles transmit their locations to the Control Center every 30 s. Database quality has been enhanced through auditing and inspection for more than 12 years since this system was established. It serves as a “single portal” for industrial waste management and facilitates informed decision making for resource exchange and material flow among various industries to achieve resource and environmental sustainability.