The　spatial　distribution　of　water　quality　status,　especially　in　water　bodies　near　intensively　urbanized　areas,　is　tightly　associated　with　patterns　of　human　activities.　For　establishing　a　robust　assessment　of　the　sediment　quality　in　an　urban　aquatic　environment,　the　source　apportionment　and　risk　assessment　of　Cr,　Mn,　Ni,　Cu,　Zn,　As,　Cd,　Hg,　and　Pb　in　sediments　from　an　anthropogenic-influenced　lake　were　carried　out　with　considering　uncertainties　from　the　analysis　methods,　random　errors　in　the　sample　population　and　the　spatial　sediment　heterogeneity.　The　distribution　analysis　of　the　trace　metals　with　inverse　distance　weighting-determined　method　showed　that　the　pollutants　were　concentrated　in　the　middle　and　southern　areas　of　the　lake.　According　to　the　self-organizing　map　and　constrained　positive　matrix　factorization　receptor　model,　agricultural　sources　(24.8%),　industrial　and　vehicular　sources　(42.5%),　and　geogenic　natural　sources　(32.7%)　were　the　primary　contributors　to　the　given　metals.　The　geogenic　natural　had　the　largest　random　errors,　but　the　overall　result　was　reliable　according　to　the　uncertainty　analysis.　Furthermore,　the　stochastic　contamination　and　ecological　risk　models　identified　a　moderate/considerable　contamination　level　and　a　moderate　ecological　risk　to　the　urban　aquatic　ecosystem.　With　consideration　of　uncertainties　from　the　spatial　heterogeneity,　the　contamination　level　of　Hg,　and　the　ecological　risk　of　Cd　in　had　a　20-30%　probability　of　the　increase.