| dc.description.abstract | Toba lake is an aquatic resources that has very important value.
Utilization of Lake impact on water quality degradation due to local people
activity, for example floating net cages. This activity can give a very significant
influence to the reduction of abundance micro-organisms such as plankton.
Purpose of this research was to determining the community structure of plankton
in Toba Lake, Haranggaol sub-district.
This research was carring out on May to June 2013 on waters of Lake
Toba, Haranggaol sub-district, Simalungun regency. This research conducted by
purpossive random sampling. There was two station location, first station, region
which contain floating net cages activities, second station, region without floating
net cages. Sampling activities conducted 4 times a month.
The results showed that there were30 genus of plankton consisting of 19
fitoplankton genus and 11 zooplankton genus. Plankton abundance data in first
station was 5812,66 ind/l and then second station was 4140,66 ind/l. The genus
diversity index on first station and second station are 3,08 and 3,38. Uniformity
index on first station is 0,39 and on second station is 0,34, this means uniformity
values from both stations relatively low. The dominance index values of both
stations is 0,04 which means there are no species is dominating other species.
This means floating net cages cultivation activity affected the plankton community
structure. | en_US |
