Zoocoenological state of microhabitats and its seasonal dynamics in an aquatic macroinvertebrate assembly (Hydrobiological case studies on lake Balaton, No. 1.)

In the years 2002, 2003 and 2004 we collected samples of macroinvertebrates on a total of 36 occasions in Badacsony bay, in areas of open water (in the years 2003 and 2004 reed-grassy) as well as populated by reed (Phragmites australis) and cattail (Typha angustifolia). Samples were taken using a stiff hand net. The sampling site includes three microhabitats differentiated only by the aquatic plants inhabiting these areas. Our data was gathered from processing 208 individual samples. The quantity of macroinvertebrates is represented by biovolume value based on volume estimates. We can identify taxa in abundant numbers found in all water types and ooze; as well as groups associated with individual microhabitats with various aquatic plants. We can observe a notable difference between the years in the volume of invertebrate macrofauna caused by the drop of water level, and the multiplication of submerged macrophytes. There are smaller differences between the samples taken in reeds and cattail stands. In the second half of 2003 – which was a year of drought – the Najas marina appeared in open waters and allowed to support larger quantities of macroinvertebrates. In 2004 with higher water levels, the Potamogeton perfoliatus occurring in the same area has had an even more significant effect. This type of reed-grass may support the most macroinvertebrates during the summer. From the aspect of diversity relations we may suspect different characteristics. The reeds sampling site proved to be the richest, while the cattail microhabitat is close behind, open water (with submerged macrophytes) is the least diverse microhabitat.

A közgazdaságtan és a szociológia határán - az identitás-gazdaságtan által felvetett elméleti kérdések (On the borders of economics and sociology. Theoretical questions raised by identity economics)

A tanulmány az identitás-gazdaságtan megközelítését és az általa felvetett elméleti kérdéseket kívánja bemutatni. E tan kiinduló tétele George A. Akerlof és Rachel E. Kranton szerint az, hogy a közgazdaságtanban használt hasznosságfüggvénybe be kell emelni az emberek énképének és az ezzel kapcsolatos egyéni mérlegelésnek a szempontjait. Ezt az indokolja, hogy az emberek társadalmi csoportokhoz/kategóriákhoz tartoznak, amelyekhez normarendszer társul, azaz ha viselkedésükkel megsértik a normákat, akkor önképük sérül, és ezáltal csökken a hasznosságuk is. A tanulmányban bemutatjuk, hogy ez a szemlélet az embereket "túlszocializált" társadalmi szereplőkként mutatja be, akik kevéssé reflektálnak a helyzetükre. További kérdéseket vetnek fel az elmúlt években végzett szociálpszichológiai és viselkedés- gazdaságtani kísérletek, amelyek rámutatnak, hogy az identitás- gazdaságtani elmélet egyik alapját jelentő normák erősen függnek szituációs tényezőktől. _____ The paper introduces the approach of identity economics and the theoretical questions raised by its arguments. According to Akerlof and Kranton, individual identity and personal calculations in relation to this identity should be incorporated into the utility function applied in economics, so that people are placed in social categories that involve normative systems. In line with this, if their actions breach the social norms, this affects negatively their self-image, so in turn decreasing their utility. The paper argues that this approach presents humans as "overly socialized" social actors who do not reflect on their situation. Further questions could be raised by experiments in social psychology and behavioral economics conducted in recent years. The results highlight the fact that the norms which serve as the basis for the theory of identity economics depend strongly on the context and given situation.