TY - JOUR
T1 - Dynamics of phosphorus fractions and bioavailability in a large shallow tropical lake characterized by monotonal flood pulse in Southeast Asia
AU - Uk, Sovannara
AU - Yang, Heejun
AU - Vouchlay, Theng
AU - Ty, Sok
AU - Sokly, Siev
AU - Sophal, Try
AU - Chantha, Oeurng
AU - Chihiro, Yoshimura
N1 - Publisher Copyright:
© 2022 International Association for Great Lakes Research
PY - 2022/8
Y1 - 2022/8
N2 - This study aims to investigate how the hydrological phase in a flood pulse dominated system, Tonle Sap Lake (TSL), affects the chemical form and bioavailability of P. For this purpose, we conducted extensive field campaigns under different hydrological phases: low-water (LW), rising-water (RW), high-water (HW), and falling-water (FW) phases from December 2016 to September 2017. The TSL ecosystem distinctly exhibited seasonality of the monotonal flood pulse between the low-water and high-water periods, in terms of not only water depth (range 0.5–8.0 m) but also water quality, suspended sediment, P dynamics (concentration, speciation and bioavailability), and trophic status. On an annual basis, the lake retained 56.2% of the external P loads, representing a major sink of P. Seasonally, P dynamics in TSL are determined by internal loading, whereas the annual inflows from the Mekong River basin and lake's tributaries are important sources of P for TSL. Total particulate phosphorus (TPP) constituted >60% of the total P in LW and decreased to <30% during HW, corresponding to the variation in total suspended solids (TSS). Soluble reactive P predominated the total dissolved P during LW (>70%) and decreased to approx. 30% during HW with decreasing TSS and TPP, suggesting the reduction of bioavailability of P in HW. Our results indicate that the flood pulse plays an important role in the chemical form and bioavailability of P in shallow lakes.
AB - This study aims to investigate how the hydrological phase in a flood pulse dominated system, Tonle Sap Lake (TSL), affects the chemical form and bioavailability of P. For this purpose, we conducted extensive field campaigns under different hydrological phases: low-water (LW), rising-water (RW), high-water (HW), and falling-water (FW) phases from December 2016 to September 2017. The TSL ecosystem distinctly exhibited seasonality of the monotonal flood pulse between the low-water and high-water periods, in terms of not only water depth (range 0.5–8.0 m) but also water quality, suspended sediment, P dynamics (concentration, speciation and bioavailability), and trophic status. On an annual basis, the lake retained 56.2% of the external P loads, representing a major sink of P. Seasonally, P dynamics in TSL are determined by internal loading, whereas the annual inflows from the Mekong River basin and lake's tributaries are important sources of P for TSL. Total particulate phosphorus (TPP) constituted >60% of the total P in LW and decreased to <30% during HW, corresponding to the variation in total suspended solids (TSS). Soluble reactive P predominated the total dissolved P during LW (>70%) and decreased to approx. 30% during HW with decreasing TSS and TPP, suggesting the reduction of bioavailability of P in HW. Our results indicate that the flood pulse plays an important role in the chemical form and bioavailability of P in shallow lakes.
KW - Flow reversal
KW - Fractionations
KW - Hydrological phases
KW - Spatiotemporal variation
KW - Tonle Sap Lake
UR - http://www.scopus.com/inward/record.url?scp=85132651628&partnerID=8YFLogxK
U2 - 10.1016/j.jglr.2022.04.005
DO - 10.1016/j.jglr.2022.04.005
M3 - 学術論文
AN - SCOPUS:85132651628
SN - 0380-1330
VL - 48
SP - 944
EP - 960
JO - Journal of Great Lakes Research
JF - Journal of Great Lakes Research
IS - 4
ER -