APPORTIONMENT OF BIOAVAILABLE PHOSPHORUS LOADS ENTERING CAYUGA LAKE, NEW YORK

作者：Prestigiacomo Anthony R^*; Effler Steven W; Gelda Rakesh K; Matthews David A; Auer Martin T; Downer Benjamin E; Kuczynski Anika; Walter M Todd

来源：Journal of the American Water Resources Association, 2016, 52(1): 31-47.

DOI：10.1111/1752-1688.12366

• environmental impacts
• rivers/streams
• point sources
• lakes
• nutrients
• phosphorus
• load estimates
• bioavailability

The integration of the phosphorus (P) bioavailability concept into a P loading analysis for Cayuga Lake, New York, is documented. Components of the analyses included the: (1) monitoring of particulate P (PP), soluble unreactive P (SUP), and soluble reactive P (SRP), supported by biweekly and runoff event-based sampling of the lake's four largest tributaries; (2) development of relationships between tributary P concentrations and flow; (3) algal bioavailability assays of PP, SUP, and SRP from primary tributaries and the three largest point sources; and (4) development of P loading estimates to apportion contributions according to individual nonpoint and point sources, and to represent the effects of interannual variations in tributary flows on P loads. Tributary SRP, SUP, and PP are demonstrated to be completely, mostly, and less bioavailable, respectively. The highest mean bioavailability for PP was observed for the stream with the highest agriculture land use. Point source contributions to the total bioavailable P load (BAP(L)) are minor (5%), reflecting the benefit of reductions from recent treatment upgrades. The BAP(L) represented only about 26% of the total P load, because of the large contribution of the low bioavailable PP component. Most of BAP(L) (>70%) is received during high flow intervals. Large interannual variations in tributary flow and coupled BAP(L) will tend to mask future responses to changes in individual inputs.

• 出版日期2016-2