rank: NA

scope: climate

rank: NA

scope: climate

rank: NA

scope: climate

rank: NA

scope: climate

rank: NA

scope: climate

rank: NA

scope: climate

basis: The dD of closed-basin tropical lakes such as Wandakara reflects the hydrologic balance of the lake, with drier conditions causing isotopically enriched lake water due to both the amount effect on precipitation and kinetic fractionation during evaporation from the lake surface, which favors the retention of deuterium relative to hydrogen in the lake water (Craig, 1961).

direction: decrease

interpDirection: decrease

scope: climate

seasonality: Annual

seasonalityOriginal: Annual

variable: effectivePrecipitation

variableGroup: P/E

scope: climate

scope: climate

basis: Short-chain (C16?C18) fatty acids in lake sediments are derived primarily from aquatic sources (Eglinton and Hamilton, 1967; Huang et al., 2002), and the principal control on their ?D is the ?D of lake water (Huang et al., 2002, 2004). ... "The ?D of closed-basin tropical lakes such as Wandakara reflects the hydrologic balance of the lake, with drier conditions causing isotopically enriched lake water due to both the amount effect on precipitation and kinetic fractionation during evaporation from the lake surface, which favors the retention of deuterium relative to hydrogen in the lake water (Craig, 1961). "

coefficient: NA

direction: negative

fraction: NA

inferredMaterial: lake water

rank: 1

scope: isotope

seasonality: Annual

seasonalityOriginal: Annual

variable: hydrologicBalance

variableGroup: EffectiveMoisture

variableGroupDirection: negative

variableGroupOriginal: I_E

coefficient: NA

fraction: NA

rank: NA

scope: isotope

coefficient: NA

fraction: NA

rank: NA

scope: isotope

basis: The dD of closed-basin tropical lakes such as Wandakara reflects the hydrologic balance of the lake, with drier conditions causing isotopically enriched lake water due to both the amount effect on precipitation and kinetic fractionation during evaporation from the lake surface, which favors the retention of deuterium relative to hydrogen in the lake water (Craig, 1961).

direction: decrease

interpDirection: decrease

scope: climate

seasonality: Annual

seasonalityOriginal: Annual

variable: effectivePrecipitation

variableGroup: P/E

scope: climate

scope: climate

basis: Short-chain (C16?C18) fatty acids in lake sediments are derived primarily from aquatic sources (Eglinton and Hamilton, 1967; Huang et al., 2002), and the principal control on their ?D is the ?D of lake water (Huang et al., 2002, 2004). ... "The ?D of closed-basin tropical lakes such as Wandakara reflects the hydrologic balance of the lake, with drier conditions causing isotopically enriched lake water due to both the amount effect on precipitation and kinetic fractionation during evaporation from the lake surface, which favors the retention of deuterium relative to hydrogen in the lake water (Craig, 1961). "

coefficient: NA

direction: negative

fraction: NA

inferredMaterial: lake water

rank: 1

scope: isotope

seasonality: Annual

seasonalityOriginal: Annual

variable: hydrologicBalance

variableGroup: EffectiveMoisture

variableGroupDirection: negative

variableGroupOriginal: I_E

coefficient: NA

fraction: NA

rank: NA

scope: isotope

coefficient: NA

fraction: NA

rank: NA

scope: isotope

basis: The shift toward grassland at AD 1000 must therefore have influenced the ?DC30 record due to biosynthetic fractionation differences between trees and grasses (Hou et al., 2007). Indeed, the enormous amplitude of shifts in ?DC30 relative to ?DC16 likely results from the replacement of forest with C4 grasslands during wet periods?a process driven by humans rather than by climate. The amplified ?DC30 response occurs because of a combination of the amount effect during wet periods and stronger isotopic fractionation by grasses relative to trees, both of which favor isotopically depleted ?DC30 (Hou et al., 2008).

interpDirection: decrease

scope: climate

variable: deleteMe

variableGroup: human-induced grass expansion

scope: climate

scope: climate

basis: The ?D of long-chain, terrestrially derived fatty acids is controlled by the ?D of the water used by plants, transpiration from leaf surfaces, and kinetic fractionation during biosynthesis (Hou et al., 2008; Sessions et al., 1999). ... "Thus, although the first-order control on leaf wax ?D in the tropics is the ?D of meteoric waters, interactions between climate and vegetation suggest the potential for complex, non-linear responses of leaf wax ?D to rainfall variability."

coefficient: NA

direction: positive

fraction: NA

inferredMaterial: soil water

mathematicalRelation: linear

rank: 1

scope: isotope

seasonality: Annual

seasonalityOriginal: Annual

variable: precipitationIsotope

variableGroup: P_isotope

variableGroupDirection: positive

variableGroupOriginal: P_isotope & Veg

basis: If changes in vegetation surrounding Lake Wandakara were mainly driven by rainfall, ?13CC30 and ?DC30 should also be positively correlated: during intervals of drought shifts toward C4 ecosystems would occur, recorded by enriched ?DC30 values. However, ?13CC30 and ?DC30 are clearly negatively correlated (Fig. 5). In fact, large positive shifts in ?13CC30 are associated with depleted ?DC30 values, and peak ?13CC30 from AD 1200 to 1440 occurs during an interval of regionally wet climate conditions (Russell et al., 2007, Russell and Johnson, 2007). This suggests that the abrupt shifts toward C4 vegetation were not caused by climate but instead by human activities on the landscape, presumably forest clearance for agriculture (Ssemmanda et al., 2005).

coefficient: NA

fraction: NA

mathematicalRelation: nonlinear

rank: 2

scope: isotope

seasonality: Annual

seasonalityOriginal: Annual

variable: deleteMe

variableGroup: Human-induced changes in vegetation type

coefficient: NA

fraction: NA

rank: NA

scope: isotope