Phytoremediation Potential of Vetiver Grass (Chrysopogon sp.) System for Improving the Water Quality of Aquaculture Ponds along the Marilao and Meycauayan River in Bulacan, Philippines

Abstract

The Marilao and Meycauayan Rivers are known to be polluted with heavy metals and organic matter due to different anthropogenic and industrial activities along the river system. Many aquaculture ponds are situated along the river system and obtain water from the river. In order to address this problem, phytoremediation or the use of plants was tested as a low-cost remediation system to reduce the pollution on the ponds. The vetiver grass was utilized because of its unique features and its ability to accumulate heavy metals. A vetiver pontoon was established on fishponds located at Brgy. Nagbalon, Marilao and Brgy. Liputan, Meycauayan. The vetiver roots and leaves were analyzed for heavy metal content. There is an accumulation of toxic heavy metals such as lead, chromium, manganese and copper in the roots and leaves. Manganese had the highest accumulated metal by the vetiver grass. It was observed that there is a significant difference of heavy metal absorption of Pb, Zn, Mn and Cr through time. The vetiver grass favored accumulating heavy metals in the roots based on the translocation factor (TF). Vetiver grass can potentially improve some water quality parameters such as lowering levels of ammonia, BOD and COD and absorb heavy metals such as Pb, Zn, Mn and Cr which are harmful to fish. The vetiver grass is a low-cost phytoremediation technology with a high potential impact in cleaning up the water in ponds.