Trends in Lakeshore Zone Development: A Comparison of Polish and Hungarian Lakes over 30-Year Period.

(1) Background: This paper presents the land use and land cover change processes in the lakeshore zone in Poland and Hungary during 30 years. (2) Methods: Land use and land cover (LU/LC) maps were prepared using topographic maps and orthophotograph maps scaled 1:10,000. The study based on GIS data and field research. (3) Results: A significant increase in the area occupied by tourist and recreational infrastructure and forests in the lake shore zone was found in both countries. In Poland, this increase occurred mainly at the expense of arable land, which was a positive phenomenon. In Hungary, however, the main threat to the lakeshore zone was the increase of built-up area at the expense of semi-natural area. While the decrease in arable land was positive from an environmental point of view, the main threat to the Hungarian lake shore zone was the increase in built-up areas at the expense of semi-natural land. The results showed a positive correlation between the area of urbanized land and the area occupied by tourist and recreational buildings on the Polish lakes. There was no such correlation at the Hungarian lakes. (4) Conclusions: The most beneficial change in land cover for the lakes was the increase in forest area in the lake shore zone in both countries studied. Taking into account the results of previous studies, three main trends of changes in land cover and land use in the lakeshore zone were identified. These results shed new light on the problem of land use around lakeshores.

Histological Aspects of the Early Development of the Digestive System of Burbot Lota lota L. (Lotidae, Gadiformes).

The ontogeny of the digestive tract was studied histologically in burbot, Lota lota L., from hatching to 42 days post-hatch (dph). At hatching, the digestive tract consisted of a straight tube with discernible digestive accessory glands (the liver and the pancreas) dorsally attached to the yolk sac. Most of the yolk sac reserves were consumed during the first 12 days and were completely depleted by 17 dph. The first PAS-positive goblet cells appeared at 6 dph, dispersed within the epithelium of the oesophagus and increasing substantially in number and distribution as development progressed. At 12 dph, the first vacuoles (neutral lipids) appeared in the intestine, indicating the functional absorption of nutrients from food. Differentiation of gastric glands was first noticed at 17 dph and was extensive by 27 dph. L. lota larvae have a morphologically complete digestive tract by 32 dph. These findings on the development of the digestive system in L. lota may contribute to a better understanding of its ontogeny and can be useful for improvement of the larval rearing techniques of this promising species for freshwater aquaculture diversification.