Latitudinalvariationsin δ Si and δ N signaturesalongthePeruvianshelf:quantifyingtheeffectsofnutrientutilizationversusdenitrificationoverthepast600years Supplementof

Supplement of Biogeosciences, 16, 2163–2180, 2019 https://doi.org/10.5194/bg-16-2163-2019-supplement

© Author(s) 2019. This work is distributed under the Creative Commons Attribution 4.0 License.

Supplement of

Latitudinal variations in δ

Si and δ

N signatures along the Peruvian shelf: quantifying the effects of nutrient utilization versus denitrification over the past 600 years

Kristin Doering et al.

Correspondence to:Kristin Doering (kristin.doering@dal.ca)

The copyright of individual parts of the supplement might differ from the CC BY 4.0 License.

Figure S1: Calculation of d¹⁵NO3- source signatures based on equations of the linear regression gained by the direct comparison of d¹⁵NBulk versus d³⁰SiBSi for the LIA (humid; a-b), CWP (c-e), the LIA (arid; f-g) and. Black lines indicate the estimated linear regression. Dashed lines indicate the resulting 1:1 utilization line.

11° S (024 TC) LR

1:1 source 7.6 ‰ 1:2

7.6‰

y = (-0.35) + 0.28x

11 °S

δ30 Si (‰)

0 0.5 1.0 1.5 2.0

δ¹⁵N (‰)

0 2 4 6 8 10 12

12° S (005 TC) LR

1:1 source 8.6 ‰

8.6 ‰ R²=0.98 y = (-1.17) + 0.42x

12 °S 0

0.5 1.0 1.5 2.0

δ¹⁵N (‰)

0 2 4 6 8 10 12

14° S (B0405-6) 15° S (003 TC) LR

1:1 source 10.4 ‰

10.4 ‰ (-1.86) + 0.41*x

R²=0.61

14-15 °S 0

0.5 1.0 1.5 2.0

δ¹⁵N (‰)

0 2 4 6 8 10 12

11° S (024TC) LR 11-12 ºS 11-12 °S

8‰

r²= 0.32 (-0.6) + 0.3*x

δ30 Si (‰)

0 0.5 1.0 1.5 2.0

δ¹⁵N (‰)

0 2 4 6 8 10 12

14° S (B0405-6) 15° S (003TC) LR

9‰

y =(-0.24) + 0.17*x r²= 0.64

14-15 °S 0

0.5 1.0 1.5 2.0

δ¹⁵N (‰)

0 2 4 6 8 10 12

LIA, arid CWP, all

c. d. e.

f. g.

11° S (024TC) 12° S (005TC) 2:1

6‰15:1

highest δ¹⁵N as source value δ30 Si (‰)

0 0.5 1.0 1.5 2.0

δ¹⁵N (‰)

0 2 4 6 8 10 12

14° S (B0405-6) 15° S (003TC)

7.5‰

highest δ¹⁵N as source value

0 0.5 1.0 1.5 2.0

δ¹⁵N (‰)

0 2 4 6 8 10 12

LIA, humid

b.

a.