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Sedimentary Oxygen Demand and Orthophosphate Release: Sustaining Eutrophication in a Tributary of the Chesapeake Bay

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Journal of Water Resources and Ocean Science

 
!" 
#$$%&"&'#$$%&&(
Sedimentary Oxygen Demand and Orthophosphate
Release: Sustaining Eutrophication in a Tributary of the
Chesapeake Bay
Tiara Nydia Moore
1, 2, *
, Benjamin Elias Cuker
1
)*+,**!-.*$/0*1.2/0*/1!$*+3*
-2*!-.*242)*/1.2+5*+*/63/1!$*+3*
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5!*
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8**%2!*,/4 *-*59$!*2(:2)*!*!(*;*$*-**
8*2+5**94*2Journal of Water Resources and Ocean Science</%//
!" 
Received3/Accepted$/Published$/
Abstract:
4   !  5 2  5**9 4*2 *     +  + */ 
** ! + + :2   * 2:* -*  !. *2 2 :* *! +
'*!%8**.+2*9!.2*!=*++
+:!*!8**+**9+:2***+***
*!!***+*/!+2:**!*:*3*!**
! +  ! *9 *! !  !.  * + *>!   * *  '
-! *! ** :.*  %*! '  *!+* *   +
2*9/    *!   . +!*9  + * 8  !*!   +
! *!2* 5**94*2*!! **
!***2?*!:2**!'.**+*
 .2 *!.*:2!):! +:+**+
*    ! 3:* !. '+: +  ! *9   * 8  ! *
*'*!!!+*:*2!**2*!!*
Keywords:
-*/5**94*2/,$/02:*/$!
1. Introduction
3 * + *9/ */ *!
** *  * !++   . @A # 
2*2 + *! 2 :. *! + *
* + *  % B ' *! *
* @A 8 *  +  +
2*9 ** )!   2! !2* +
 2/  = * :2 !*! 
*!   *  *!  !2
! $! (:2 )*!  $() @CA 8
*!*!*+****>%
*!'@"A8*2 *!% *! '+!*2
* */ *  % *! ' +  *!
  + 2*9 @&A ?  **
!*!9/*!!* :2 !*!+
 * *! ! 3   * *
*+ *!/!**!*!*!
*% *! '5*+  *! 
++2 *! +* * * *
! + :. 2*9  @/ A 8
.+!*9   * *9  .* +
*  !++ @/ A -. *+ 
*! *  !!/ * *! + 
! * * **  *!  *
2!@/A$*2!
2/ D**!E * * * 
 8**%2!*,*!4 *-*59$!*2(:2)*!*!(*;*$*
-**8*2+5**94*2
.!@A
3 *  *   2:*  **
2/  *  *   *2 &F/
*2  **  *   G+ + ,:
%G, @CA 3  5**9 4*2F 2:
> *  * * *  %G,F/  +* 
.!  *2 * @A 8 *!.
2:*  +! 2  *+* * :2
*++*++:+ 
!****!!!@/&
AH*:*+/*/
**!*/2:*/*2
8 **  *! 2:* **! 
*  * *  **2 @A
)  *! /  +* *2 */
  !! !2 +  * @/ &A 8
+ *+*/ **2  *! 2
*/ *  5**94*2@A 8+*!
!.++**+***2
8  *2 * **! 2 * * !2 *!
2*:+*2/
 ** + 9 !/ ! !*! *! !2
2*9@&/ A $ * *  ++
+  **! . !     
 4*2  *+!   ! +
**!2:**..!@/A
8  +  *   :*  .*2
*.***2**2+
5**94*2?!**/    * 
! *  **! !  ! + 2:*/ 
. *! 2 2:* ( *    *
!! .* !   
= *  * B 2:*
:!   4*23 * * *
+$()  * :2!/ * *
 *  + ' *! +  !
8 *!!  /  !! : *
*! * ** ** * 2   4 *2/
 * :2 *! ' *  !
8!*****!++
*2 *.  *  * *  *   
**
2. Materials and Methods
2.1. Study Area
8 5**9 4*2   * *2   1!
$*  9  8 4*2 !* **  % H9/
'2.**/ )**/ ,*2*!/ <*/ ? <*/
*! ) +5* @A8*!
 *     * *! ***
+* ** * +  #* * *
*! *! *!!.  *!
&C   * !.  +  4*2 *!
!*!*+*=*2@//A
8 !2 * !!   0* ;./ *
*2+ 5**94*2*0* 1.2
0*/ <* 8 *  ! + 
*  *2  !! I 59/ $
59/*!0*;.J/8*80*
;. C 9 *! *! 2 2 +
0*/ <* 8 .     +
0* ;*! * *      
! +  5**94*280*;. 
!   !* / I 59 *! $  59/
*+  *. .**! * +&"
3 !   4*2 * @&/ &/ A/  2
!:!:****!
2:*
Figure 1. A) Map of Chesapeake Bay, star indicates Hampton River system. B) Collection sites.
I*+?*;*!(*$ 
Table 1. Hampton River system collection sites GPS locations.
Station Location Latitude Longitude
 I59 %KF" ?"KF&
 I59 %KF ?"KFC
 $59 %KFC ?"KF
 $59 %KF ?"KFC
C 0*;. %KF"" ?"KFC"&
" 0*;. %KF" ?"KF"
 0*;. %KFC& ?"KF
2.2. Sample Collection
0*! *  ! 2! ./*   
I 59/  $ 59/ *!  0* ;. 
I +  8      *!
**>   0* ;*! *2 5
*  !  CC  / C  *
!***-* **!*!
   *  ! +   
** * -*  ! *! C  +
* .2   + ! 3 * */ 
!* ! *  *9 *  * 
 ! 2  * * +  *. 
! **  * 8 !** +
!*!**!***
  ** **2  '   *
.!!20*1.2/!*!!
..!*
3 *  /  *2 &  & ''8/
*   / *! !.! :2 "C 
&L  *! +   *  *
*   *.  ! 3 !  C J8
H$ # H$# :2 *!+
* * J * */  *! *!
!!!G*G'$M"5:8*/
*! * ;*2*  * !  !  * !
"8!*2**!
:2  * 2    / *! * * >
**2!*!N+F*!*!2
2.3. Experimental Procedures
1  * H$# / *  * *!
**2+ */*2/*! !.!:2 
 **2 8 H$#  * !  *
!    * .    *. 
!* +*/  .  +
!/ *! ! 2   *!
*>!8 ! * **  :
+ * .2 ** ! *! 2 
!* !* 2 8 : !! *2 *
* :2 :!  !.   =
++
(  *  !/   
*!*!*!*O5*8
$+ C& ' #* 8   
9!2+*/ *!!.!:2(
 * *! *: ./ 2  +  
* + *  ! +  9 3+  9
  !/ *   * * * .! +
* **2  -'3 ! "C 8
*    + **  * /
*=* / *! .*. 8  **/ *
!  + * *  !+!   *
 (  * !    *=*   
+*+*/*!*!*
**2>!*:5
**! +   !*2 + 9!
*9*2*:2
*.! *!  :2 * * * * 3+ 
:2 * *>! * L *  
* + * * .! + *
**2 3+ * **/    *! *
O5/ *! *   * + * * .!
+ * **2 8  *  
9! + */ *! !.! :2 ( 
**! *:./2 !*2
+ ** *! **!  !*2+  9 8 *
*! + C/ & *! O5 ** * 2
:!2 4*2 8 *!!
 * * ** ** :2 2 :! 2
!
2.4. Calculations and Statistics
3 ! :2 !*! $() ** 
! +  * +  *  2
*  :2 !*! !! +  *
2  ?5() +  $() +! + *
! !  8 *  :2
* .  +   *+ *
:2*  !  *  $() + *
* 8 :2 * *+  + 
**!+*:2*
!**9+!.!:2%:/ .
+ *  * ! 2  * +
:2  

  ! *  !.!! 2 
*!**+!8*
Table 2. Formulas used to calculate 1) Change in SOD, 2) SOD per day, 3) Annual SOD, 4) PO4 release.
Calculation Formula Variable 1 Variable 2
P$()Q R
(


SR
(


 R
(


Q$()

 R
(


Q

+*2
(


!

Q R
(


SR
(


:<


: R
(


Q$()

*+ R
(


Q*$()

3$()

Q $()

!

:!*2 $()

!

Q*$()

!
 
T'(
Q  R
'(


SR
'(


R
'(


Q'(


R
'(


Q'(


+*2

C 8**%2!*,*!4 *-*59$!*2(:2)*!*!(*;*$*
-**8*2+5**94*2
#!**+$()*!?5()
.  ** 2/ !** +  6- C 6 8
, $*  !  *:*  !++
** * * ? *! *  **
2 ! + O5  " !*2/ O5 *2
&!*2/CO5+*"!*2/&O5*+*
*2&!*2/*!O5"!*28!**
*!+ ** * + $()*! ?5() 
!! * * * +  0* ;.
8*28*
(* * * ! + * +
 *  2 *  *
* !! +  *2  + 
* * !! + *
! !  8 +   * *
!***+*8*
3 * !**   *! **!  -: 3
3%(<3 * !! +! 2 * 892 0$)  
! +*  $() *! * 3
*!  * !  !+2  * 
:2*!'*3 *! *+*!
 ;$! <  8  + * 
!*!** *!*** Q
+**2
3. Results
3:! $() *2*9! */ 
 * **!    *
* + &  
 

 0./ $() *
2  * 5 * * 5 J  3%(<3
**2**+*+*!
:2!*!/*!.*.**28*
Figure 2. Annual SOD for the Hampton River Tributary plus Tukey HSD results. A) The colder temperatures (4C winter and 9C early fall) had a similar effect
on SOD. B) 15C (early spring) and 28 (late summer) had a similar effect on SOD. C) 22 (early summer) required the highest SOD, and was not similar to any
of the other temperatures.
Table 3. ANOVA Table for annual SOD. All temperatures have a significant effect on SOD.
Df Sum Sq. Mean Sq. F value Pr(>F)
   & " &777
;!*  & 
$+! N777F N77F N7F CNF NF
3*0*;.*2 !**
*+$()*!*$()+*+
* *9! * O5  *! + " L + 
* ** $()  L +  ** :2 !*!
!*CO5/*!&L*O58$()*
! & *!O5 *2  L *! L
* +  ** ! ( * ** * $()  +
 * *  ?5() 8*  8 $() *!
?5() ! *!*2*!
!*!
Table 4. Sediment Oxygen Demand vs Water Column Oxygen Demand over an annual cycle. The percentage SOD is greater than WCOD was also calculated.
Temperature Mean SOD (g O
2
m
-
2
season
-
1
) Mean WCOD (g O
2
m
-
2
season
1
) % SOD > WCOD
O5 C&" " C
O5 "C  "C
CO5  "" 
&O5  " 
O5 "  
3*)*! C(


 &"(


 C&
8 * * * +  0* ;.
*2*+  9+*:**U'
J  8 * * * + 
0*;.*2*+9+***!
I*+?*;*!(*$ "
*  U '   % * *. 
!* * * +  * 
*9   !/  .  !*
* * +  !   *
J  3 *! !+! *
 :2 *! * +:   +*/ 
 *: * *. * * * + ' * 
**!*QC8 *+'+:*!
**2!!J
Figure 3. Anoxic vs. Aerated P flux. Mean P flux +/- 1 standard error for the
Hampton River Tributary. (-) indicates direction of flux.
Figure 4. Hampton River P flux. Range of P flux across the tributary under
varying oxygen conditions.
Figure 5. Orthophosphate release vs. sediment oxygen demand for the
Hampton River Tributary after one week of anoxia.
8*+'* +  ! * *
  *! ! :2 !*! 8 *
$()*!+* * *+ *
*: ! +  9 **!   *  *
 **2 * !! * 
 .* + C
JC
4. Discussion
(  2 * ' * +  ! 
   $() *2 * * .
 **  *! ( !
!! :. ' +: + ! ! *: */
*! !! !* * @/
"A)*!2/
! ++* *2*!!*
.* ! @C/ A #  0* ;.
2 * "L +  ** $() ! ! 
O5*/  !*  *! *2
+*J#**2:!* $()
!  !  O5 *  
* * *2 *   
* 3/   !  +* +
2:*   *  . . 2*
*  * @A 8 5**9 4*2 
* * +! $()F   ,*2 *! I O5
* * +!  3 O5 @A 8 ! 
*!  * +   * 2 * 
*/*!!+*!!!
1! :*/ * !  2!:! +
  J *! ** , + !*
* * *   ! @/ &A 1!
*:*/J*!,*!!2****8
!*!+*!+*!**
*  * 8  +* *
!*  0 *! * * ! . 8
!. * + * +  !  
*! *:* @&A3!2 **2> :2
!**+ 4*2. 2*!!*D
*!!  *! !! 2:.E @A
3 !2  " ! *  D! 
*  *! * *!.
** 2:* .**2  5**9 4*2E @A
,.*2/I*.!!+.!*
'2   !!*! 2 * *
*>*   4*2 ! @"A/ 
! !2  ** +!   !2
1!**/2*!+2+'
+!   !/ *! 2 !!  * 2
*'@"A 3/*.::2
!   5**9 4*2/ 2:* *  
+*2***!**2*
 2* !  *!    ! 
*>   ! @A 0*  */ *
*  2 + * *! 2:*
*2 ! *  **  2
**!@A
5. Conclusion
(   * +  0* ;. *2 
 8**%2!*,*!4 *-*59$!*2(:2)*!*!(*;*$*
-**8*2+5**94*2
 *2  / . + 2: ./ 
! !*! C  &C  (  ! J 
**! $()/   .! *  ! * 
*2  + :2    *.2
*0*;.28 + *
 ! :2 !*! * *!  2: .
*! =  * 8 = 
*/* *+2/**
**   *!!*+ ' 
*  3 / **  !*! *
++ **. *
=*2      * * + 
*+5**94*2,***9
  *  * 2 + ' *!  
+  !  *2 *  !*
*!*!=*
Acknowledgements
? * * 9*  !    9
+*2 , 5* G*2 *! , 3*!* ?
8*9*   ,* *! -.* $
)* * 0*1.2/<3/ 1$3J! *
.!! 2  6. ,* ; 5*.
$5
References
@A ) 4/ D-++ + 2:*/ *!  ** 
2:* *! /  ** + *! +/E
-*/.C/4/"S/
@A I ) 0*2/ ? ; 42/ 5 ? V+ / *! V < ?!/
D02:*  5**9 4*2/ &C 6 *
 *   *!*! . +/E-*/ .
//"S"C/
@A $ ? %:/ D5** * * 3 !+/
* */ *! + /E (*/ . /  /
&&S&/&&C
@A 5 5 J *! % , ;/ D82(H* $ * +
5**94*2 ?*W*21 5-W136#5,
-*,!/EI3?;3I3?*;3/
.&/C/&S/$
@CA ,0/'4/*! I- V9*/D4-:**!
4*52'*$!/E 3;.
,*$/."//SC/
@"A I - 5/ D( .. * ! + 
**X* /E ,* - ' $/ .
/SC/
@A )3 $ *! G ,*++/D$!(:2 )*! 
5* 4* +6*9-/E I G*6*9;/ . /
/S/
@A ; 0*  */ D5! * 2
-**!2:* ***!**
* 2/E  J  -2 *! 
-.//.&//S"
@&A ?42*!?V/D%**!:2
 2 ! * * * *2
*!/E,*-'$/./CSCC/&C
@A ) I 52/ I 5*/ ; <*=$2/ *! 5 ,
)*/D-2!2:*/E02!*/
."&//S&/&
@A $V$!.*/;I)Y*>/*!G;5/D4*
* ! :2 ./   .* +
*/E'6$(/.//
@A ? ; 42/ , 3 5 5*/ - , 4*2/ 5 6 $
0!9/ I 6 02/ *! I , 8*/ D(:2 *!
%-:**$!?*#+**G*
$2 *! 5= + -* *! 5** )**/E
-**!5*/.//S/,*
@A 5,5*/VV9/*! 4 $ 0*/ D#*. *!
*. ++ +  *   *
2/E-6/.//SC/
@A 'I I/85;/*! ,5)/ D;*>2
*!***/E--./.C/
/CSC/,*C
@CA % % ;***  */ D% 5*   ,
;. *! $2 ;   3! * 5*
$+/E-*/.&//"/&&"
@"A )$*.*/ % % ;***/; - 8/) IZ/ *! ?I
?*/D'!+G++,:2:*
 .**  , ;.  *!/E 6
(*/.//&CS&C"/
@A ,6*/D?*!.**.**2+2:*
5**9 4*2 5* + .  *![/E
G2;6/./C/S/"
@A I,8* */ DW*+2  +++  *!
 !.! ( 2 *! 2:*  5**9 4*2
 * ! 2!!2*S* !/E I
,*$2/.&/&SC/
@&A ; I )*>/ D(.. + 02:* *!  ?!/E I
-.W*/.//C/
@A ? 5 6 *! ; ) $>/ D02:*  **9 *2
* ? ++  * 2
H9;./E-**!5*/./
/S&/&
@A ;I)*>/G; 5/*! ) , )*/D3* +
 ! + *  * +  **
=*2   <* 5**9 4*2/E I -: ,* 4
-/.C/S/
@A 0 $ 6/ ; I )*>/ I $ 0/ *! 6 5 $*++/
D02:**!2.2  V* **
*/E ,* ' 4/ . C/  /  CSC"/
"
@A ?,V/I , 8*/) I 52/) G/ *! I )
0*2/ D8*  + ** 2:*  
*!*!2*/E4/."//
&CS/&
@A ?42/?,V/5G(/*!<$V!2/
D% +: *  !* +*  
! > + * ** * *2/E  -*
'./&/&S&
I*+?*;*!(*$ 
@CA < ;* *! ) )*/ D$!  *! *
*+: 2!.+4(/
J*/E02!*/./&SC&/&&
@"A $;I/;VV99*!*/)I4!/,-4!/
)6$*9/*!)'I*/D(***>*
!* 2 !*2!
 **9 *2/E-. $ 8/ . &/  /
CSC&"/C
@A I 8* *! ? ,* V/ 02:*!! + 
*!25**94*2/.C

@A 'I8**!;3 4*9/ D5**9 4*2.2 *!
+**++!6/!*/*!
/E;$!,*$/./S/"
@&A I 4 '.* *! ' I 6!*2/ \,* + 2*
+!#,! 3/3>I/,!'
,** + 2* **2 + *=* !
4*;*5;5'/#&&'
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02:* 5**9 4*2/E4/ . "/ /
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... Once in the turbid state, positive feedbacks act to maintain this state. Decreased circulation, sediment and organic matter accumulation, resuspension, release of nutrients from the sediments, and anoxic and sulfidic conditions act to keep lagoons and estuaries in their degraded state (Munkes 2005;Troell et al. 2005;Viaroli et al. 2008;Moore and Cuker 2018). Conditions that promote algal mat formation tend to decrease the probability of recovery (Moksnes et al. 2018;Watson et al. 2018). ...
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Chapter
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The effects of nutrient loading from the Mississippi River basin on the areal extent of hypoxia in the northern Gulf of Mexico were examined using a novel application of a dissolved oxygen model for a river. The model, driven by river nitrogen load and a simple parameterization of ocean dynamics, reproduced 17 yr of observed hypoxia location and extent, subpycnocline oxygen consumption, and cross-pycnocline oxygen flux. With Monte Carlo analysis, we illustrate through hindcasts back to 1968 that extensive regions of low oxygen were not common before the mid-1970s. The Mississippi River Watershed/Gulf of Mexico Hypoxia Task Force set a goal to reduce the 5-yr running average size of the Gulf's hypoxic zone to less than 5,000 km 2 by 2015 and suggested that a 30% reduction from the 1980-1996 average nitrogen load is needed to reach that goal. Here we show that 30% might not be sufficient to reach that goal when year-to-year variability in ocean dynamics is considered.