L. Forró szerk.: Miscellanea Zoologica Hungarica 9. 1994 (Budapest, 1994)

Andrikovics, S.; Hadnagy, T.: Ecological evaluation of aquatic invertebrates distribution of Apátkút Creek (Visegrádi Mountain, Hungary) in winter

Finally, the relationships between species and aquatic insect-assemblages to substrate have to be examined. In the creek 4 kinds of substrates can be found: stones, detritus, creek-side vegetation reaching the water and sand. The rhitron organisms, with the exception of Halesus sp., are bound mainly to stones and they can be found in small numbers of individuals on sandy bottom (Fig. 8). It can be explained by the substrate-forming-effect of current. Silting up is possible only in the case of low water velocity, so the dissolved oxygen content is smaller, there are no hiding-places and food, that is why no aquatic larvae were found on this type of bottom. Detritus can also be found in places with low water current, but in contrast to sand it has one advantage for larvae: this detritus is food. That is why larvae live here, although in low numbers (mainly Baetis rhodani and Halesus sp.). II ^> >. '5 _o u > B c o d C3 E io cx <4-l o u -T. Ti u c tfl 3 > <L> .S g (í-l ,—< O u X: E 3 d T3 C rt U CA o c o Cfl s*-< C 00 c 'S) U in M >> 'o _c > c o e a £ u & l*_I c <u u c CM •a 'S 1 tt—

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