| dc.description.abstract | River water environment consists of abiotic and biotic components that
interact with each other. When interactions are both disrupted, there will be
changes that led to the aquatic ecosystem becomes unbalanced. This research has
been conducted in May to July 2013 in Belawan Headwaters River. This research
used Purpossive Random Sampling method. There are 2 locations station, Station
1: Pertampilen village, District Pancur Batu as an active area of sand dredging
activities, Station 2: Greetings Tani village, Batu district Pancur as areas that are
not contained sand dredging activities. Sampling activities were conducted 4
times once/week. The research aim to know determined the abundance of
plankton in Belawan Headwaters River.
The results showed 20 species of phytoplankton and 1 species of
zooplankton, there were consists of 11 classes: Bacillariophyceae (7 species),
Coscinodiscophyceae (1 species), Conjugatophyceae (1 species),
Zygnematophyceae (4 species), Chlorophyceae (5 species), Ulvophyceae (1
species), Trebouxiophyceae (1 species), Eurotatoria (1 species). The average
abundance of plankton ranged from 4.11-5.19 ind / L. Diversity index ranged
from 1.03-2.95 and dominance index ranged from 0.57-0.046. Water quality
parameters, such as temperatur 24-26oC , phosphate 0.045-0.064,nitrate 0.924 -
1.314, nitrite 0.011-0.021, ammonia 0.318-0.491, turbidity 5.34-17.22. Based on
abudance of phytoplankton, concluded that the activities that occur in the upper
reaches of the Belawan affect the productivity of plankton in the river. | en_US |
