DIVERSITY OF BENTHIC MACROINVERTEBRATES IN MARGARACA FOREST STREAMS (PORTUGAL).

Structure and diversity of the benthic macroinvertcbrate fauna were st~tdied in two deciduous forest streams in Central Portugal. In the three sampling occasions. 120 tax-cl were collected from the two streams. Number of tci,xci per sampling occasion ranged from 53 to 60. Macroinvertebrate densities ranged from 1465 to 2365. Insects were the most abundant taxonomic group (280?h) in all samples. Detritivorous invertebrates were numerically dominant in both streams, representing 62 to 85 5 % of the total macroinvertebratc community