||The objective of this study was to investigate the spatial and temporal|
distribution of black carbon (BC) and possible sources by analyzing BC contents
in core and sediment trap samples collected from Kao-ping submarine Canyon and
surficial sediments collected from Love River, Chianjen River, Kaohsiung Harbor,
Kao-ping River and adjacent coastal area. In addition, sediment core and trap
samples of Kao-ping submarine Canyon, and suspended solids of Kao-ping
estuary were analyzed to estimate the BC loading from Kao-ping River and the
flux in Kao-ping submarine Canyon.
The concentrations of BC ranged from 0.38 to 3.29 mg g-1 in this study. The
results we found in coastal sediments were comparable to those in Asia, but lower
than those in America and Europe. Black carbon found in surficial sediments of
D2, L1 and of stations from Love River, Chianjen River and Kaohsiung Harbor
were contributed from vehicle emission or coal combustion. Correlation
coefficients of BC versus total polycyclic aromatic hydrocarbon (PAH)
concentrations, combustion PAHs, total organic carbon (TOC) and grain size were
significant in the sediments of Kao-ping River adjacent coast.
Regrading to the temporal distribution of BC in Kao-ping submarine Canyon,
BC and PAHs increased in the deposited sediment after 1970, that was probably
related to prosperous industrial activities for last decades in Taiwan.
Surficial sediments could be grouped into three clusters by hierarchical cluster
analysis (HCA). Results of principal component analysis (PCA) showed principal
component 1 (PC 1) could explain 35 % of total variances. Significant PC 1
compound loadings were found mostly from high molecular weight PAHs which
derived mainly from combustion processes. This result was supported by the
significant correlation (p<0.05) of PC 1 scores versus BC concentrations which
were also mainly derived from combustion.
BC fluxes for sediment cores, S1 and S37, and sediment trap of Kao-ping
submarine Canyon, 0.59 g m-2 yr-1, 2.03 g m-2 yr-1 and 23 g m-2 yr-1, respectively,
were comparable to those reported for surficial sediments in literature. However,
BC fluxes in this study were lower than those in the sediments from Mouth of
Providence River, Palos Verdes Shelf and New England Harbors, but higher than
those in pelagic sediments of the Pacific Ocean. In addition, we also measured BC
concentrations in suspended solid samples to estimate loadings of Kao-ping
estuary which ranged from 33 to 1765 kg day-1 with an average of 602 kg day-1.
Annual BC loading of Kao-ping River was roughly estimated as 29.55×104 tons
which was lower than that of the Mississippi River.