Biotechnology in Japan 1984 — a mini-review

Major developments in Japanese biotechnology in 1984 are reviewed. Besides industry and academia, research associations (companies and governmental research institutions guided by ministries) carry out joint fundamental research in biotechnology. Another important long-range aspect is the Technopolis Concept, which aims at decentralizing research and technological activities.     

Biozönotisches Testverfahren (PICT-Konzept)

Goal and Scope

A community test is introduced usingin situ periphyton communities and the pollution induced community tolerance for ecotoxicological testing. It was the aim of the study to evaluate the feasibility of the test for the assessment of xenobiotics and contaminated environmental aquatic samples.

Methods

The herbicides Isoproturon and Prometryn were tested using standardised microphytobenthic communities of differing contamination. A pulse-amplitude-modulated fluorescence based method was used to detect the impact of the herbicides on the photosynthetic system of the microalgae.

Results and Conclusions

Despite the variability of the ecosystem (samples were taken from different sites and varying taxonomy throughout a period of two months), the tests show high sensitivity and good reproduction features. EC₅₀ values of 0.025 mg L^?1 for Isoproturon and 0.016 mg L^?1 for Prometryn were evaluated. These effect concentrations ranged in the same order of magnitude as the results derived from cell reproduction inhibition tests withScenedesmus vacuolatus (0.029 mg L^?1 for Isoproturon and 0.012 mg L^?1 for Prometryn). For Isoproturon, the test was able to differentiate effect concentrations for single algal classes within natural communities. The test was used to assess a contaminated effluent entering a stream (Spittelwasser) in the region of Bitterfeld. The effluent originate from a local chemical industry site, where Prometryn was produced for 4 decades. According to the PICT-concept (pollution induced community tolerance), we hypothesed that periphyton taken downstream of the effluent was more tolerant to Prometryn than uncontaminated communities. It could be shown that the herbicide caused a shift in the concentration response relationships of communities from different contaminated sites, indicating the development of tolerance. We conclude that the test using periphyton communities and considering the development of tolerance is able to evaluate a causal analysis of chronic effects of pollutants on community level. The multi-species test usingin situ communities reflects a higher biological organisation level than a single species laboratory test.

Outlook

The PICT-concept could be used for ecological risk assessment of pollutants in the environment bridging the gap between single species laboratory testing and time consuming mesocosmos and field studies.     

非洲野生动物:是否必须给予补贴--对保护地可持续性融资问题的一大贡献

因为多种多样的生态、经济以及其他方面的原因，保护非洲的生物多样性刻不容缓。经济利益的驱使并非首要问题，然而忽视这一因素将不可避免地导致保护目标不能得以实现。     

Estimation of mercury content in tailings of the gold mine area of Poconé, Mato Grosso,Brazil

As in many other parts of the world, gold is produced in the surface mining region of Poconé, Mato Grosso, Brazil, using mercury. The goal of this investigation was to estimate the amount of mercury in certain tailings and to determine the area of the land that has been contaminated by the gold mining operations. Mercury concentrations from 2 to 495 ng/g (dw) were determined in the tailing materials. It was observed that only isolated sites were acting as central points of contamination. Using digital Landsat satellite data (The-matic Mapper) and aerial photos, the sites degraded by the mining were classified, and their total area was estimated to be 12.3 km² in the region of Poconé. It was estimated, that 4.9 km² were occupied by the contaminated tailings. The mean height of the pile slags was determined to be 4.5 m. From the experimentally calculated average density of the material in the tailings, 2.01 g/cm³, the total mercury content in the piles of tailings was estimated to be 1600 ± 350 kg.