S. Mahunka szerk.: Folia Entomologica Hungarica 47/1-2. (Budapest, 1986)
agreement on the basis of cultural relations which allows regular exchanges of research workers of the two countries. By making use of this opportunity we worked out a schedule aiming to explore the animal communities and the invertebrate fauna of the various waters and soils of Vietnam. Besides our research capacity enables us to survey the nutrient status of the most characteristic terrestrial and aquatic biotopes of the different geographical regions. The nutrient status research would cover the organic carbon, total nitrogen, available inorganic nitrogen, total phosphorus and available phosphorus. By knowing the composition of the fauna, the animal community, the nutrient status and the type of ecosystem present there, then it might be possible to estimate the ecological potential of the region. In order to realize our conjectures, in the beginning of 1986 we travelled to Hanoi, where we were the guests of the directorate of the Institute of Biological Resources and we had extensive debates with the leaders and the members of the scientific staff. With a view to coordinate the research project and to gain a better knowledge of the possibilities and conditions prevailing there, that might come useful in the final draft of the schedule, we travelled far and wide and became acquainted with several characteristic regions of Vietnam. We herewith present the schedule for our research programme: The survey of the ecological potential and the animal communities of terrestrial and aquatic ecosystems in Vietnam A schedule for the research programme in the years of 1986-1990 1. The survey of terrestrial and aquatic ecosystems in the environs of water-power stationreservoir complex under construction on the river Song Da, near Hoa Blnh. Recording the changes after water flooding. A comparison of results with the similar Hungarian project to be constructed on the river Danube at Nagymaros-Bős. 2. The basic survey of the terrestrial and aquatic animal communities in various landscapes of Vietnam. Furthermore, the study and analysis of le|ss investigated animal groups from taxonomic and Zoogeographie points of view. The plotting of nutrient status (organic carbon, phosphor,nitrogen) of the various soils and waters. Besides coordinating our plans, the other equally important aim of our trip was to begin an intensive collecting of the Invertebrate fauna of aquatic and terrestrial habitats. We arrived in Hanoi through Moscow, Karachi and Calcutta on the 15th of January, 1986. After a few days of negotiations in the capital and some smaller collectings in the environs, we travelled about 100 km north to Tam Dao. Here we made extensive collectings in the skirt of montane rain-forest and true tropical forests. In spite of the winter season we experienced very favourable weather conditions, e.g. night lamping was made at a temperature of 22-24°C, and even the early morning temperature did not drop below 15°C. After returning to Hanoi, we proceeded to Tanh Hoa, where we collected, unfortunately, mostly in devastated forest stands (Ngoc Lac, Lam Son), and partly In the belt of the sea-shore (Sam Son), mostly in cultivated areas. Here the weather turned rather rough, it was cool and foggy, and the frequent rains much hindered our collecting activities. Our third trip was made in the province of Ha Son Binh (30th January). In the environs of Hoa Blnh, Da Bac and Tan Lac, again In good weather conditions, we made successful collectings. It was rather warm, even in the night the temperature was around 25°C. Unfortunately, owing to a small accident, we had to stop our collectings and finished our work earlier than we originally planned. While collecting principally we applied the following methods and covered the subsequently listed groups of animals: 1. Singling specimens, beating the foliage, using the sweeping net and lamping (Honda generator, MV-lamp 300 W); imagines of aquatic insects (Trichoptera, Ephemeroptera, Plecoptera). 2. Securing specimens living on or in the soil (worms and arthropods). Sampling Nematodes, collecting earthworms by digging and sprinkling formaline on the soil. Taking samples of soil, litter, moss and moulting debris, etc. Other samples were sifted, and the sifted samples extracted in Berlese-funnels and Moczarsky-Winkler bags. 3. In order to obtain as many Insects as possible we used lamps, the singling method, and the sweeping net. The detailed collecting data are given below:
