Abstract
After cut off of inflowing water, Lake Paro, an oligomesotrophic lake lost littoral zone, an important region for the aquatic ecosystem. For the first step of restoration, the artificial vegetation island was installed. The concentration of nutrients in lake water was not sufficient for the growth of macrophyte as total phosphate was ranged from 58 to 83 μg L−1. In order to overcome this problem, the hydrophobic substratum for bacterial attachment was selected as buoyant mat material of the artificial vegetation island. In this medium, total phosphate and total nitrogen were ranged from 190 to 1,060 μg L−1 and from 4.9 to 9.1 mg L−1, respectively. These concentrations were high enough for macrophytes growth. After launching 1,800 m2 of AVI in Lake Paro, the macrophytes, Iris pseudoacorus and Iris ensata, grew well after five years of launching without the addition of fertilizer. Furthermore, fishes were plentiful under the artificial vegetation island, and ducks were observed on the artificial vegetation island. Bacteria using sunlight as energy source and self-designed ecotechnology can be used as an alternative method for the restoration of disturbed littoral zone in oligo-mesotrophic lakes.
Highlights
Following construction of the Keumgangsan Dam in Democratic People’s Republic of Korea in 2001, about 60% of main inflow into Lake Paro was cut off
After one week of submergence in Lake Paro, the total nitrogen (TN) and total phosphorus (TP) concentrations in the interstitial water were much higher than initial concentrations
Interstitial water samples collected by gravity force and squeezing had TP concentrations ranging from 0.4 mg L−1 to 5.1 mg L−1 and TN concentrations from 38.5 mg L−1 to 489.0 mg L−1
Summary
Following construction of the Keumgangsan Dam in Democratic People’s Republic of Korea in 2001, about 60% of main inflow into Lake Paro was cut off. The water level in Lake Paro was lowered from 181 m to 150 m following the construction of the dam (Figure 1). After the decline in water level, this oligomesotrophic Lake Paro experienced problems related to fish habitat such as degradation of the littoral zone and lose of spawning and refuge areas. These problems resulted in a reduction in fish populations such as the common carp (Cyprinus carpio) and mandarin fish (Siniperca scherzeri) [1]. The littoral zone at Lake Paro cannot be naturally revegetated because of these steep slopes and frequent fluctuations in water level. Natural vegetation islands comprised of submerged, and emergent macrophytes can deteriorate the fishery and lake water quality [3]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
