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Natural inputs and anthropogenic influences on lakes arid their catchments are reflected in the sediment record. In the present study, the extractable organic compounds from sediments in the Chaihe catchment of the Dianchi watershed were analyzed to characterize source inputs. Results show that the sediments are dominated by odd numbered n-alkanes (n-C-16-n-C-33), maximizing at n-C-17, n-C-29 and n-C-31. Aliphatic hydrocarbon may be composed of terrestrial plants and bacteria. The values of delta C-13(27), delta C-13(29) and delta C-13(31) of n-alkanes exhibit a range from -33.27 parts per thousand to -25.46 parts per thousand from -35.76 parts per thousand to -28.47 parts per thousand and from -33.67 parts per thousand to -27.42 parts per thousand, respectively and three records strongly covary with depth, falling within the range of C-3 plants in the study area. An isotopic model revealed C-3 plant contribution to sedimentary organic matter (OM) ranging from 40.75% to 97.22%. The values of ACL(27-33), CPI27-33, OEP, Paq, Pr/Ph, (C-27 + C-29)/2C(31), (C-21 + C-23 + C-25)/3C(17) and nC(26)(-)/nC(27)(+) are consistent with the C-3 plant predominance. A constant CRS model gave the accumulation rates ranging from 2.69 to 8.46 mm a(-1) spanning 1885-2010. It was concluded that OM transport in the Chaihe catchment was influenced strongly by human activities resulting in enhanced eutrophication. (C) 2014 Elsevier B.V. All rights reserved.