Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes...
-
Upload
colton-twining -
Category
Documents
-
view
224 -
download
8
Transcript of Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes...
![Page 1: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/1.jpg)
Francesco Scarton1, Daniele Are1, Andrea Rismondo1 and John Day2
Accretion and elevation changes on salt marshes and reedbeds of the lagoon of
Venice: ten years of data
1 SELC soc. coop., Via dell’Elettricità 5/d, Marghera (VE), Italy email:[email protected]
2Coastal Ecology Institute and Department of Oceanography and coastal Sciences,Louisiana State University, Baton Rouge, LA 7080, USA, email: [email protected]
SELC biologia e geologia applicate
![Page 2: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/2.jpg)
a total area of 550 sq. km, with about 37 sq. km of salt marshes, 3.5 sq. km of reedbeds and 50 sq. km of tidal flats. Mean tidal range is 0.6 m (1.1 m spring tide), three hydraulic basins.
The largest lagoon in the Mediterranean, hosts endemic species, and vegetation communities with restricted distribution in southern Europe.
The lagoon ofVenice:
SELC biologia e geologia applicate
![Page 3: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/3.jpg)
Field stations in four habitat types:
• Saltmarshes (N and S basin): 13 st.
• Reedbeds (in the NW corner of the lagoon): 2 st.
• Dredge islands (artificial sites): 2 st.
• Tidal flat: 3 st.Installed in1993-1997, most of them were part of monitoring projects performed until 1999 on behalf of the Italian Ministry of Public Works- Water Authority in Venice and its concessionaire Consorzio Venezia Nuova.
After that, we did new measurements in 2001 and summer 2004 (11 stations): 4 st. still to be measured, 5 st. destroyed.
SELC biologia e geologia applicate
![Page 4: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/4.jpg)
Reedbeds in
Venice lagoon
SELC biologia e geologia applicate
![Page 5: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/5.jpg)
Lost salt marshes
Remaining salt marshes
•Lack of sediment inputs
•Natural and man-induced
subsidence
•Wave erosion
FACTORS OF SALT MARSHES FACTORS OF SALT MARSHES
DISAPPEARINGDISAPPEARING
SELC biologia e geologia applicate
![Page 6: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/6.jpg)
Most common saltmarsh species
and their elevation
SELC biologia e geologia applicate
MHW
![Page 7: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/7.jpg)
Map of saltmarsh vegetation(for about 50% of the lagoon)
SELC biologia e geologia applicate
![Page 8: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/8.jpg)
Distribution (in red) of dredge islands in 2004
Ranging in size from 0.3 to 30 ha, mean of 10 ha.Most are made of silty sediments, the remaining are sandier.Mean elevation of the former close or below mean high water level; the latter are usually higherDifferent age (oldest: 14 years)
SELC biologia e geologia applicate
![Page 9: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/9.jpg)
PART TO BE REMOVED
WOODEN PILEWOODEN PILE
1.00 m a.s.l.
0.60 m a.s.l.
m.s.l.
1.00 m
1.00 m a.s.l.
0.60 m a.s.l.
m.s.l.
- 1.00 m a.s.l.
Hydraulic net
Hydraulic net
DREDGED MATERIAL
Reconstruction of eroded salt marshes with dredged sediment
SELC biologia e geologia applicate
![Page 10: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/10.jpg)
Reconstruction of a
disappeared salt marsh
SELC biologia e geologia applicate
![Page 11: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/11.jpg)
The network of Venice stations
SELC biologia e geologia applicate
012345678
1 2 3 4 5 6 7 8 9 10 11
years
no
. of
stat
ion
s
![Page 12: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/12.jpg)
The Sedimentation Erosion Table (SET)
9 pinsbubble level
pipe benchmark
ca -4 m
From Cahoon et al., 2002
SELC biologia e geologia applicate
![Page 13: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/13.jpg)
Conceptual diagram for elevation change/accretion
from Cahoon et al., 1995
![Page 14: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/14.jpg)
Details of a SET station:C e ll A C e ll B
S E T s u p p o rtin g p ip e
S e c to r o f m e a s u re m e n ts
F e ld p s a r m a rk e r
SET re m o va b le a rm
4 m
9 readings in each sector, 36 readings per cell, 72 per station.Accuracy estimated at + 2.0 mm
length of thepin above the arm
marker
SELC biologia e geologia applicate
![Page 15: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/15.jpg)
Kaolin markers
1994
2004
SELC biologia e geologia applicate
![Page 16: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/16.jpg)
New field data
Dese 1 (reedbed)
0
1
2
3
4
5
6
7
8
Jan
-93
Jun
-94
Oct
-95
Mar
-97
Jul-
98
Dec
-99
Ap
r-01
Sep
-02
Jan
-04
May
-05
cm
elevation change (SET)
accretiony = 0.0446x - 0.407, R2 = 0.95, p<0.001(X= months since beginning)
Accretion: 0.6 cm/yrElev. ch.: 0.5, 11 ys.
Dese 2
-1
-0,5
0
0,5
1
1,5
2
2,5
3
Ma9
3
No9
3
Fe9
4
Ju94
Oc9
4
Ja95
Ap9
5
Ju95
Oc9
5
Ja96
Ap9
6
Oc9
6
Fe9
7
Ju97
Oc9
7
cm MARKERS
SET
Accretion: 0.6 cm/yrElev. ch.: 0.5, 4 ys.
SELC biologia e geologia applicate
![Page 17: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/17.jpg)
Laghi (saltmarsh with Juncus )
0
1
2
3
4
5
6
7
8
Ja
n-9
3
Ju
n-9
4
Oc
t-9
5
Ma
r-9
7
Ju
l-9
8
De
c-9
9
Ap
r-0
1
Se
p-0
2
Ja
n-0
4
Ma
y-0
5
cm
elevation change (SET)
accretion
y= 0.0013 x -43.4, r2=0.85, p<
y = 0.0409x + 0.0038, R2 = 0.8736
Accretion: 0.5 cm/yrElev. ch.: 0.5 cm/yr, 11 ys.
SELC biologia e geologia applicate
![Page 18: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/18.jpg)
S. Felice 1 (saltmarsh with Sarcocornia )
0
1
2
3
4
5
6
7
8
Jan
-93
Jun
-94
Oct
-95
Mar
-97
Jul-
98
Dec
-99
Ap
r-01
Sep
-02
Jan
-04
May
-05
cm
elevation change (SET)
accretion
y = 0.0235x - 0.2941, R2 = 0.87, p<0.001
Accretion: 0.3 cm/yrElev. ch.: 0.3, 11 ys.
SF1SF2
creekpond 5 m
![Page 19: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/19.jpg)
S. Felice 2 (saltmarsh with Spartina )
0
1
2
3
4
5
6
7
8
Jan
-93
Jun
-94
Oct
-95
Mar
-97
Jul-
98
Dec
-99
Ap
r-01
Sep
-02
Jan
-04
May
-05
cm
elevation change (SET)
accretion
y = 0.0381x - 0.2485, R2 = 0.87, p<0.001
Accretion: 0.4 cm/yrElev. ch.: 0.4 cm/yr, 11 ys.
SELC biologia e geologia applicate
![Page 20: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/20.jpg)
Torson 1 (saltmarsh with Puccinellia -Limonium )
-1
0
1
2
3
4
5
6
7
No
v-93
Ap
r-95
Au
g-9
6
Jan
-98
May
-99
Oct
-00
Feb
-02
Jun
-03
No
v-04
Mar
-06
cm
elevation change (SET)
accretion
y = 0.0327x - 0.7039, R2 = 0.84, p<0.001
Accretion: 0.4 cm/yrElev. ch.: 0.4, 11 ys.
T1
T2
![Page 21: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/21.jpg)
Torson 2 (dredge island)
-8
-7
-6
-5
-4
-3
-2
-1
0D
ec-9
3
May
-95
Sep
-96
Feb-
98
Jun-
99
Oct
-00
Mar
-02
Jul-0
3
Dec
-04
cm
elevation change (SET)
Elev. ch: - 1.8 cm/yr, 4 ys + 0.3 cm/yr, 7 ys
June 1997
SELC biologia e geologia applicate
![Page 22: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/22.jpg)
SELC biologia e geologia applicate
P. Cane 1(saltmarsh with frontal erosion)
-1
1
3
5
7
9
11
13
No
v-93
Ap
r-95
Au
g-9
6
Jan
-98
May
-99
Oct
-00
Feb
-02
cm
elevation change (SET)
accretion
Elev. ch: 0.7 cm/yr,Acc: : 1.7 cm/yr
![Page 23: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/23.jpg)
Observed rates at 14 stations
SELC biologia e geologia applicate
Accretion Elevation Shallow Years Elevation Dominantchange Subsidence above s.l. species
cm/yr cm/yr cm/yr m
Dese 1 0.6 0.50 -0.10 11 0.28 PhragmitesDese 2 0.6 0.5 -0.10 11 0.36 PhragmitesLaghi 0.5 0.5 0.00 11 0.29 JuncusSan Felice 1 0.3 0.3 0.00 11 0.35 SarcocorniaSan Felice 2 0.4 0.4 0.00 11 0.29 SpartinaTorson 1 0.4 0.4 0.00 11 0.39 PuccinelliaTorson 2 11 dredge islandFossei nat 0.4 0.4 0.00 8 0.42 LimoniumP. Cane 1* 1.70 0.70 -1.00 8 0.43 SarcocorniaEx Salina 0.45 0.3 -0.15 8 SpartinaBuello 0.9 0.8 -0.10 7 0.23 JuncusP. Vecia 0.9 0.8 -0.10 7 0.35 PuccinelliaChioggia 0.4 0.5 0.10 5 0.35 SarcocorniaTessera 1 0.4 0.4 0.00 4 0.39 SarcocorniaTessera 3 0.3 0.1 -0.20 4 0.36 SarcocorniaP. Cane 2* n.a. -4.7 4 -0.26 tidal flatTessera 2* n.a. 0.8 3 -0.23 tidal flatTessera 4* n.a. -1.5 3 -0.35 tidal flatFossei art* 0 -0.6 -0.60 1 0.31 dredge islandCampalto* 0.3 -0.1 -0.40 1 0.28 Limonium
Mean (excluding *) 0.50 0.45 -0.05
two trends
![Page 24: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/24.jpg)
Elevation change vs accretion(12 st.)
y = 0,8597x + 0,0297
R2 = 0,8526
0
0,2
0,4
0,6
0,8
1
0 0,2 0,4 0,6 0,8 1
Accretion (cm/yr)
Ele
va
tio
nc
ha
ng
e (
cm
/yr)
SELC biologia e geologia applicate
4 st.
2 st.
![Page 25: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/25.jpg)
Accretion vs elevation(12 st.)
y = -1,9246x + 1,1595
R2 = 0,2619
0,0
0,2
0,4
0,6
0,8
1,0
0,00 0,10 0,20 0,30 0,40 0,50
Elevation above s.l. (m)
Ac
cr.
(cm
/yr)
SELC biologia e geologia applicate
![Page 26: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/26.jpg)
Accretion vs. Elevation Linear Trajectories at 49 Saltmarsh SettingsGrouped by Regional Setting
0
2
4
6
8
10
12
14
16
18
-3 -1 1 3 5 7 9 11
Linear Elevation Trend (mm/yr)
Line
ar A
ccre
tion
Tre
nd (
mm
/yr)
US Atlantic - NE (Can) US Atlantic - SE U.S. Gulf Coast US Pacific
New South Wales Victoria Mediterranean
SELC biologia e geologia applicate Courtesy of Tom Spencer,Cambridge University
![Page 27: Francesco Scarton 1, Daniele Are 1, Andrea Rismondo 1 and John Day 2 Accretion and elevation changes on salt marshes and reedbeds of the lagoon of Venice:](https://reader035.fdocuments.us/reader035/viewer/2022062404/551bee6b550346af588b655f/html5/thumbnails/27.jpg)
SELC biologia e geologia applicate