Characterization and heavy metal pollution assessment of sediments from Laguna de Bay, Philippines
Santillan, Bertrand Aldous L.
Characterization and heavy metal pollution assessment of sediments from Laguna de Bay, Philippines / Bertrand Aldous L. Santillan - Los Baños : University of the Philippines ,2018. - xiv,183 leaves 27 x21cm.
Thesis (Master of Science in Environmental Science) -- University of the Philippines Los Baños, December 2018.
Laguna de Bay, the largest lake in the Philippines, is threatened by worsening
environmental quality due to the negative impacts of urbanization and industrialization.
One of the issues pressuring the lake is shallowing due to increased sedimentation. Plans
are underway to dredge the sediments to restore the lake. However, little is known about
the quality of the lake sediments especially its pollutant concentrations. In this study,
sediments in the South Bay wereinvestigated for its geochemical characteristics and heavy
metal pollution. Sediment cores from the upper >I m ofthe lakebed were collected from
eight locations around the South Bay. The cores were macroscopically analyzed before
subsampled at 2.5 cm intervals, dried, analyzed for water content and total organic matter
content, sieved up to 63 m and analyzed for grain size anti to 1 heavy metals usingXRF
and ICP-OES. Resul s ofthe analyses showed that water content differs between cores, the
average total OM is at 11 %, and grain size and total HM differ among core locations and
depth. Ten HM ofindustrial significance were assessed using four single indices: EF, Igeo,
CF and AF, and four integrated indices: PLI, NPI, mCd, and RI. It was found that Sn and
Pb are highly enriched and strongly contaminated, while Sb has moderate enrichment and
contamination, the rest are minimal. As is the least enriched and polluted. Ordinary kriging
interpolation was used to show the spatial distribution of pollution indices. It was found
that the San Cristobal River mouth area is highly polluted, primarily by Sn, while the mid-
lake is moderately polluted, primarily by Pb. Potential sources ofSn and Pb were identified
by inspecting the industrial activities in the area, as well as other lake dynamics. The
ecological risk assessment showed considerable risk in the San Cristobal River mouth and
moderate risk in the mid-lake. Decision and policy makers should consider the Sn, Pb, and
Sb pollution in the management of sediments and the monitor the discharges of industrial
parks to the lake.
Sediments (Geology)--Environmental aspects --Philippines
Heavy metals--Environmental aspects--Philippines
Pollution--Environmental aspects--Philippines
Laguna de Bay (Philippines) --Environmental conditions
Characterization and heavy metal pollution assessment of sediments from Laguna de Bay, Philippines / Bertrand Aldous L. Santillan - Los Baños : University of the Philippines ,2018. - xiv,183 leaves 27 x21cm.
Thesis (Master of Science in Environmental Science) -- University of the Philippines Los Baños, December 2018.
Laguna de Bay, the largest lake in the Philippines, is threatened by worsening
environmental quality due to the negative impacts of urbanization and industrialization.
One of the issues pressuring the lake is shallowing due to increased sedimentation. Plans
are underway to dredge the sediments to restore the lake. However, little is known about
the quality of the lake sediments especially its pollutant concentrations. In this study,
sediments in the South Bay wereinvestigated for its geochemical characteristics and heavy
metal pollution. Sediment cores from the upper >I m ofthe lakebed were collected from
eight locations around the South Bay. The cores were macroscopically analyzed before
subsampled at 2.5 cm intervals, dried, analyzed for water content and total organic matter
content, sieved up to 63 m and analyzed for grain size anti to 1 heavy metals usingXRF
and ICP-OES. Resul s ofthe analyses showed that water content differs between cores, the
average total OM is at 11 %, and grain size and total HM differ among core locations and
depth. Ten HM ofindustrial significance were assessed using four single indices: EF, Igeo,
CF and AF, and four integrated indices: PLI, NPI, mCd, and RI. It was found that Sn and
Pb are highly enriched and strongly contaminated, while Sb has moderate enrichment and
contamination, the rest are minimal. As is the least enriched and polluted. Ordinary kriging
interpolation was used to show the spatial distribution of pollution indices. It was found
that the San Cristobal River mouth area is highly polluted, primarily by Sn, while the mid-
lake is moderately polluted, primarily by Pb. Potential sources ofSn and Pb were identified
by inspecting the industrial activities in the area, as well as other lake dynamics. The
ecological risk assessment showed considerable risk in the San Cristobal River mouth and
moderate risk in the mid-lake. Decision and policy makers should consider the Sn, Pb, and
Sb pollution in the management of sediments and the monitor the discharges of industrial
parks to the lake.
Sediments (Geology)--Environmental aspects --Philippines
Heavy metals--Environmental aspects--Philippines
Pollution--Environmental aspects--Philippines
Laguna de Bay (Philippines) --Environmental conditions