Between late 1978 and mid-1979, two major coastal vegetation plantings were completed on dredge material in Tampa Bay, Florida. On the dredge material extension of Sunken Island, 1.64 ha of Smooth Cordgrass was planted via 12-cm ‘plugs’ on 1-m centres, in rows 2 m apart. After 14 months, this planting is showing 93.4% survival. On dredge-material island CDA-D, 0.52 ha of mangroves (63% Black and 37% White) was planted via 0.3–1.9 m transplants on 2-m centres. After 13 months, this planting is showing 73.3% survival.

The nature of these two plantings permits a comparison of their cost and man-power requirements. The labour requirements for Smooth Cordgrass were 995 man-hours/ha as opposed to 2,541 man-hours for mangrove transplanting. Smooth Cordgrass requires $4,566/ ha for plugs ($1.03/plug) while mangrove transplants cost $11,459/ha ($3.92/transplant). These costs are for comparison only, as they entail primarily labour and neglect most of the indirect costs that may be experienced.

An analysis of benefits for both salt-marsh and mangrove planting indicates that Smooth Cordgrass provides greater primary production on a g C/m2 basis than mangroves. Both plantings serve as colonial waterbird nesting habitat and source-areas for further planting, but Cordgrass does so in a shorter time-frame. When weighing the positive and negative aspects of both, Spartina alterniflora is preferred over mangroves where both are present.

In the City of Gloucester, Massachusetts, 30% of the Soft-shell Clam (Mya arenaria) beds in a tidal inlet known as the Annisquam River are not harvestable owing to the discharges of untreated sewage from the surrounding area. A large proportion of the total area of the clam-flats has been closed to clamming because of exceedingly high levels of coliform Bacteria in the clams and in the water. These polluted areas represent a ‘loss’ of resources for the community, and they were surveyed in 1980 to determine the number and value of Clams which could have been harvested if only the sewage discharges had been controlled.

In the productive areas of the closed-to-fishing flats, which totaled 25.9 ha, the densities of Clams larger than 2.5 mm were found to be statistically the same on the 9 flats sampled and averaged 122.3 per m2. The average number of legally harvestable Clams (those with shells more than 51 mm in length) was 23.3 per m2, and the total yield that could have been harvested in 1980 was estimated at 6 × 106 Clams. Assuming that only 50–60% of the Clams would actually have been harvested in a year (i.e. 3.2 × 106 animals), the local community lost $332,400 in retail sales alone for lack of adequate sewage treatment facilities. Locally, 70% of the harvest goes into the restaurant trade where a bushel (35.2 1), which contains some 1,600 animals, retails for $210, and 30% is sold fresh at $64 per bushel.

The overall objective of development should be to improve the quality of people's lives, yet economic development without due environmental protection commonly leads to ecological or environmental impacts which have the reverse effect of reducing the quality of human life. A table showing some of the major environmental impacts that can result from uncontrolled rural development is presented to illustrate the fact that developmental activities with no environmental protection can be very seriously detrimental to the rural environment. Therefore, an environmental impact assessment, both short-term and long-term in scope, should be made of any major development scheme as a basis for drawing up strategies for minimizing undesirable impacts. Although a number of techniques are available for such impact assessment, the checklist and matrix approaches appear to be the most suitable for use in Southeast Asia, where impact studies are only just beginning to be introduced.

The most recent meeting discussing the Kyoto Protocol focused on market-based mechanisms to reduce greenhouse gases. This could pave the way for initiatives that allow polluters to offset their emissions if they buy carbon sequestered through reforestation (Sandalow & Bowles 2001). But rather than lose credit when the trees are harvested, investors must continue to track the sequestered carbon once trees become timber. I examined trade statistics for the best-tracked timber species, namely mahogany, Swietenia macrophylla King (Meliaceae). Although mahogany is regulated by one of the most restrictive trade agreements, the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), I found discrepancies in USA trade statistics of c. 30%, representing c. US$ 100 million over the last 4 years. For comparison, I also calculated differences in trade data for all sawnwood, according to the United Nations Food and Agricultural Organization (FAO); discrepancies between USA and exporter reports were c. 38%. Large accounting problems must be solved before sequestered carbon should become a globally traded commodity.

Human perception of biological variation is an important and understudied issue in the conservation and management of natural resources. Here, we took a novel approach by asking 1152 participants, primarily college biology students, to score examples of insect mimicry by the number of distinct kinds of animals they saw. Latent class analysis successfully separated participants based on their accuracy of perception as well as demographic information and opinions about biodiversity. Contrary to expectations, factors such as childhood experience (growing up in urban, suburban or rural areas) did not affect the ability to see biodiversity as much as political views (location on a spectrum from liberal to conservative) or the position that biodiversity is important for the health of the environment. We conclude that research into effective measures of biological education should consider the connection between personal views and perceptions of natural variation.

Many professionals regard the study of history as a waste of time. I can understand this sentiment where research proceeds rather automatically and largely without concern for possible social censure, but where societal forces directly complicate the agenda involved, there is reason for proceeding with a more open mind. Ignorance of the past invites reinventing the wheel; not only with respect to specific theories or models that were designed in some past era but never fully tested, but also to more general points of view that may extend beyond the immediate science of the question. Meanwhile, within most fields of knowledge there are constant attempts at reinvention; in many of these theory or research paradigms may become stale or stagnant. But just as often societal evolution may produce new agenda, including ones that require wholly new perspectives. The biodiversity movement of the past fifteen years is a good example of such forces in action. Human population pressures increasingly test the planet's ability to renew itself, a momentum that has caused conservationists and planners to move away from single-species and intra-national forms of management and toward larger-scale, interdisciplinary, understandings of the socio-natural processes at work.

This paper addresses current and future concerns regarding the air-pollution situation in China, and focuses on reduction of particulates', SO2, and CO2, emissions in China's electric power-generation sector. Technical aspects of control methods include an assessment of innovative approaches such as enhanced oil recovery (EOR). Suggestions are made pertaining to the technical planning and management aspects of air-pollutant control.

In a technological context, improving coal-use efficiency, increasing the proportion of coal pretreatment, and using EOR technology, should be considered; these measures have proven effective and relatively economical elsewhere. If the measures could be adopted in China's electric power-generation sector, as much as about 50% of the particulates, 34% of the SO2, and 95% of the CO2, emitted from power-plants, could be removed. If fully engaged, these actions would improve China's air environment significantly.

In a planning and management context, five suggestions are made with respect to air quality regulations: administrative measures, coal prices, developing ‘clean’ energy systems, reforestation, and transferring to new energy-saving and pollution-controlling technologies. In addition to domestic efforts, active engagement in international cooperation would be extremely beneficial to China.