Describe the successful biomanipultaion of finland's lake vesijarvi.

In Lake Vesijarvi, there is large amounts of cyanobacterial blooms which have accumulated over several years back in 1980s. It was caused by an excessive amount of an  inner nutrient which was caused from the growing amount of cyprinid fish. The displacement of these fishes in order to decrease impurities i.e. known as biomanipulation which had taken place each summer for a continuous 5 years totally . After the occurence of second biomanipulation process, scientists have discovered about the disappearance of noxious blooms, there was decrease in cyanobacteria by 33% from the initial quantity. During the period of 5 years of testing, the overall transparency of the water increased by 1.5m and it was also proved that the deed of biomanipulation to disinfect the toxic body of water.

the answer is a) a shiprock was formed by igneous process

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