Implementation of ecological modeling as an effective management and investigation tool: Lake Kinneret as a case study

The need for scientifically based management of lakes, as key water resources, requires the establishment of quantitative relationships between in-lake processes responsible for water quality (WQ) and the intensity of major management measures (MM, e.g. nutrient loading). In this paper, we estimate the impact of potential changes in nutrient loading on the Lake Kinneret ecosystem. Following validation of the model against a comprehensive dataset, we applied an approach that goes beyond scenario testing by linking the lake ecosystem model DYRESM–CAEDYM with a set of ecosystem variables included in a pre-assessed system of water quality indices. The emergent properties of the ecosystem predicted from the model simulations were also compared with lake data as a form of indirect validation of the model. Model output, in good agreement with lake data, indicated differential effects of nitrogen and phosphorus nutrient loading on concentrations, and major in-lake fluxes, of TN and TP, and dynamics and algal community structure. Both model output and lake data indicated a strong relationship between nitrogen loading and in-lake TN values. This relationship is not apparent for phosphorus and only a weak relationship exists between phosphorus loading and in-lake TP. The modeling results, expressed in terms of water quality, allowed establishment of critical/threshold values for the nutrient loads. Implementation of the ecological modeling supplemented with the quantified set of WQ indices allowed us to take a step towards establishment of the association between permissible ranges for water quality and major management measures, i.e. towards sustainable management.     

Measuring the impact of the pet trade on Indonesian birds

The trade in wild animals involves one‐third of the world's bird species and thousands of other vertebrate species. Although a few species are imperiled as a result of the wildlife trade, the lack of field studies makes it difficult to gauge how serious a threat it is to biodiversity. We used data on changes in bird abundances across space and time and information from trapper interviews to evaluate the effects of trapping wild birds for the pet trade in Sumatra, Indonesia. To analyze changes in bird abundance over time, we used data gathered over 14 years of repeated bird surveys in a 900‐ha forest in southern Sumatra. In northern Sumatra, we surveyed birds along a gradient of trapping accessibility, from the edge of roads to 5 km into the forest interior. We interviewed 49 bird trappers in northern Sumatra to learn which species they targeted and how far they went into the forest to trap. We used prices from Sumatran bird markets as a proxy for demand and, therefore, trapping pressure. Market price was a significant predictor of species declines over time in southern Sumatra (e.g., given a market price increase of approximately $50, the log change in abundance per year decreased by 0.06 on average). This result indicates a link between the market‐based pet trade and community‐wide species declines. In northern Sumatra, price and change in abundance were not related to remoteness (distance from the nearest road). However, based on our field surveys, high‐value species were rare or absent across this region. The median maximum distance trappers went into the forest each day was 5.0 km. This suggests that trapping has depleted bird populations across our remoteness gradient. We found that less than half of Sumatra's remaining forests are >5 km from a major road. Our results suggest that trapping for the pet trade threatens birds in Sumatra. Given the popularity of pet birds across Southeast Asia, additional studies are urgently needed to determine the extent and magnitude of the threat posed by the pet trade.     

Das neue Chemikalienprogramm von UNEP Chemicals

The UNEP International Register of Potentially Toxic Chemicals (IRPTC) was created by the UN Conference on the Human Environment of 1972. Its influence and co-operation in the 80ies with other international programmes of the WHO, FAO, OECD, and EC for the control of chemicals is presented here. The follow-up of the UN Conference on the Environment and Development (1992) created three new bodies that are to implement chapter 19 of Agenda 21 (Environmentally Sound Management of Chemicals): The UN Commission of Sustainable Development, the International Forum on Chemical Safety, and the Interorganisation Programme for the Sound Management of Chemicals. This UN Conference also brought about a new orientation ofIIRPTC. In 1996, IRPTC was renamed as UNEP Chemicals and has been functioning in three major fields since then: The international convention on Prior Informed Consent, the international convention on the control of Persistent Organic Pollutants and, finally, a continuation of is traditional field of information exchange on chemicals.     

Contamination of Clams with Human Norovirus and a Novel Hepatitis A Virus in Cameroon

Food and Environmental Virology - Shellfish constitute an important protein source but may be contaminated by viruses from various origins. A study performed on clams collected in Cameroon showed a...     

FIELD EVALUATION OF SOME PUBLIC INVOLVEMENT TECHNIQUES1

ABSTRACT: Public involvement in water resources planning is receiving much current attention, and there is a need to examine systematically how different public involvement techniques work in practice. The following techniques were among those used to involve the public in a recent Corps of Engineers’study of flooding on San Pedro Creek in Pacifica, California: a public workshop, citizen information bulletins (CIBs) and questionnaries. Interviews were held with 75 study participants to evaluate the effectiveness of these techniques. The interviews indicated that various study participants felt positively about the particular workshop format employed and about the use of a communications specialist to train workshop leaders. There were mixed reactions to the effectiveness of the CIBs and questionnaires. Although many individual citizens felt that the CIBs and questionnaires were useful, some of the Corps planners felt that CIBs and questionnaires would only be “cost-effective” on large studies and/or where the questionnaire response rate was high. The interviews led to a number of specific suggestions regarding how the extent of public involvement could be increased in future water resources planning studies.