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High spatial patchiness of methane  p i lp High spatial High patchiness hi off methane h concentrations concentrations over the flat landscape of the  t ti over the th flat fl t landscape l d p off the th Ebro River Delta (NW Mediterranean) Ebro River Delta (NW Mediterranean) J.‐A. J. A. Morguí Morguí1,2,*,, X. Rodó X. Rodó1, 3, R. Curcoll , R. Curcoll1, A. Àgueda , A. Àgueda1, L. Sánchez , L. Sánchez‐García García1, P. Occhipinti , P. Occhipinti1, A. Font , A. Font1,4, M. Ealo , M. Ealo1, C. Grossi , C. Grossi1, M. Nofuentes , M. Nofuentes1, R. Arias , R. Arias1, O. Batet , O. Batet1 1

3Institució Catalana de Recerca i Estudis Avançats;  IInstitut Català de Ciències del Clima (IC3);  tit t C t là d Ciè i d l Cli (IC3) 2 Ecology Dept., Universitat de Barcelona;  E l D t U i it t d B l I tit ió C t l d R i E t di A t 4 4 Environmental Research Group, King's College London. E i t lR hG Ki ' C ll L d ( (* corresponding author: jamorgui@ic3.cat) p g j g )

The Ebro River Delta The Ebro River Delta

A1

The Ebro River Delta landscape of a 320 km2 extension p is composed p g y , largely g yp agroecosystem, paddyy fields distributed at both sides of the river, and of natural lagoons and marshes along the coast of the Mediterranean Sea (A). (A) This area is protected for birdlife, birdlife and it holds the Ebro Delta Natural Park. Park Rice farming and seafood activities harvesting are the main human activities.

L Lagoon Estella ((DEC) )

RIVER SIDE (RIV)

A2

In order to protect the huge aquatic birds communities, communities the rice fi ld are usually fields ll kept k t flooded fl d d for f a long l ti time after ft the th harvesting h ti season, usually ll untill late l January.

DELTA LEFT DELTA LEFT  SIDE

RICE FIELD RICE FIELD  left

EBRO RIVER

A5

RICE FIELD  right h

Lagoon g Tancada (TAN)

DELTA RIGHT RIGHT SIDE SIDE Iberian Iberian 

Peninsula

A

This means a long time is left for anaerobic decomposition of organic matter (like straw and bird depositions). Through February p and March rice fields dryy and thereafter soil p preparation labors can start ((end of March). ) Startingg in mid‐April, p , new water channelized from the Ebro River floods the paddy fields allowing rice to grow, to flourish and to mature, flourish, mature before rice harvesting in September. September In late January water channels are closed in a new cycle to get the fields dried for aeration and new seeding. seeding (B, (B C, C D)

A4

A3 Fig. A: Ebro River Delta (NW Mediterranean) and field sampling scheme (A); Flooding  Fig A: Ebro River Delta (NW Mediterranean) and field sampling scheme (A); Flooding stages at the paddy fields and lagoons  (B‐D); and field instrumentation (E‐G). t t th dd fi ld dl (B D) d fi ld i t t ti (E G)

Aim of the study Aim of the study In 2011, 2011 as to prevent the proliferation of an invasive species (Pomacea insularum) spreading over the Northern rice paddies, paddies the closure of the left water channels was anticipated to the end of the rice harvesting season (early O t b ) This Thi extraordinary t di ti (only ( l undertaken d t k for f 2011 and d 2012) turned t d outt in i a different diff t timing ti i off the th drying d i up off soils il from f th left l ft fields fi ld whereas h th right i ht ones were kept k t flooded fl d d until til late l t January J ( Fi A). A) October). action the the (see Fig. The aim of the study presented here is to take advantage of this large scale casual and unique “experiment” for evaluating the temporal and spatial variability in the distribution of atmospheric Greenhouse Gases originated from both the p patchiness due to farms owners’ uses and the role of the gglobal water management of the Ebro Delta agroecosystem. g g y

D

M th d l i l Description Methodological Description Methodological i ti

C

Continuous measurements of CO2, CH4 and H2O were obtained with a portable instrument designed for aircraft research (Picarro G‐2301‐m, Cavity Ring‐Down Spectroscopy at 1Hz), powered with batteries and mounted on a car (E). This car circulated at 60 km/h in order to obtain an p g A). ) Air was sampled p and filtered from an inlet in the front p spatial resolution around 20 to 30 m, followingg a track of 70 km ((red line in Fig. part of a car ((F), ), at ~ 40 cm above gground ((G). ) No drying y g system y was used: the effect of water vapor p was corrected with the build‐in Picarro G‐2301‐m system. The instrument is periodically calibrated with a set of seven NOAA standards. Moreover discrete gas samples (flasks) were obtained at five sites (yellow points in Fig. Fig A1‐5) for other GHGs analysis in the laboratory (Gas Ch Chromatography). t h ) The measurement campaigns p g covered:

B F E

• The diurnal cycle: Three tracks were followed, one at sunset, other at dawn, and the third at the new sunset. • The Th rice i crops managementt cycle: l ¾(Seasonality): After the harvesting in September, September the closure of the left water channels was effectuated in November 11th 2011. 2011 In December 20th and 21st 2011 continuous measurements were conducted for the effects of organic matter decomposition in flooded (both right and left) areas. Next N t sampling li was in i January J 23rd and d 24th 2012, 2012 just j t att the th days d th right the i ht water t channels h l closed, l d that th t is, i right i ht fields fi ld were still till fully f ll fl d d whereas h h water table bl in i the h left l f ones was deep d i the h soils. il The Th third hi d campaign i shown h h h time i h water gateways from f flooded, the in here was at the the the two river sides opened, but with the soils still kept dry (April 18thh and 19thh 2012), and just after the labors for aeration and seeding have finished.

G

¾(Soil‐water conditions): ¾(S il di i ) Both B h sides id flooded fl d d (20/21‐Dec), (20/21 D ) right i h side id flooded fl d d vs. left l f side id dried d i d (23/24‐Jan), (23/24 J ) and d both b h sides id dried d i d (18/19‐Apr). (18/19 A )

Atmospheric p methane concentration variability. variabilityy 40.8

[1920 - 1940) 40.7

40.6 0.6

0.65

0.7 Longitude (º)

0.75

40.6 0.6

[2400 - 2500) 40.75 [2300 - 2400)

[2200 - 2300)

[2200 - 2300)

[2200 - 2300)

40 7 40.7 [2100 - 2200)

Latitud de (º)

[2300 - 2400)

Latitud de (º)

[2300 - 2400)

[2100 - 2200)

[2000 - 2100)

[2000 - 2100) 40.65

[1900 - 2000)

[1900 - 2000)

[1900 - 2000)

< 1900

< 1900

< 1900

40.6 0.6

0.65

0.7 Longitude g (º) ( )

0.75

40.6 0.6

0.8

19-Apr-2012 05:20:46 - 19-Apr-2012 09:36:42

0.8

40.75

[1895 - 1900)

[[1890 - 1895)) 40.7 [1885 - 1890)

40.65

[1880 - 1885)

< 1880

Latittude (º)

Latitude (º)

>=1900

[1895 - 1900)

[1890 - 1895) 40.7 [1885 - 1890)

40.65

[1880 - 1885)

< 1880 40.6 06 0.6

0 65 0.65

0.7 0 7 Longitude (º)

Dawn /2

0 75 0.75

08 0.8

December 21st----------DEC----------------RIV-----------------------TAN 21st DEC RIV TAN FLEXPART model simulation in backward mode of the Potential Surface Influence (PSI, 0 0-300m 300m layer) for the wind arriving at the Ebro Delta in December 21st and January 24th at dawn . PSI representation for pixels with a Residence time of the air in those pixels lasting more than 100 seconds are also depicted for three points: ¾DEC (Lagoon site in the river Ebro left side, side A1 in Fig A) ¾RIV (River (Ri b k site, bank it A3 in i Fig Fi A) ¾TAN (Lagoon (L site i in i the h river i Eb right Ebro i h side, id A5 A in i Fig. Fi A)

January 24th----------DEC------------------RIV-----------------TAN 24th DEC RIV TAN A Apriil 18th h-1 19th (20 ( 012 2)

40.75

[1890 - 1895)

[1880 - 1885)

0.75

>=1900

[1895 - 1900)

[1885 - 1890)

0.7 Longitude g (º) ( )

40.8

>=1900

40.7

0.65

19-Apr-2012 11:40:32 - 19-Apr-2012 15:24:28

40.8

Sunset /1

40 7 40.7

Jan nua ary 23 3rd-24 4th h (2 201 12))

24-Jan-2012 15:06:48 - 24-Jan-2012 18:49:46

[2400 - 2500)

0.8

08 0.8

0.8

[2400 - 2500)

18-Apr-2012 17:09:18 - 18-Apr-2012 21:30:23

0 75 0.75

0.75

>=2500

40.8

0.7 0 7 Longitude (º)

0.7 Longitude (º) ( )

40 8 40.8

40.65

40.65

0.65

>=2500

40.65

Latitude (º))

< 1880

0.8

[2000 - 2100)

40 75 40.75

[1880 - 1900)

>=2500

[2100 - 2200)

0 65 0.65

[1900 - 1920)

24-Jan-2012 06:33:29 - 24-Jan-2012 10:26:27

40 7 40.7

0.75

40.7

< 1880

40.75

0.7 Longitude g (º) ( )

[1920 - 1940)

40.65

[1880 - 1900)

40 8 40.8

0.65

[1940 - 1960)

[1900 - 1920)

40.65

40.75

40.6 06 0.6

40.75

[1940 - 1960)

Latitude e (º)

Latitude L e (º)

40.75

23-Jan-2012 15:35:54 - 23-Jan-2012 19:08:20

40.6 0.6

>=1960 > 1960

>=1960

40 8 40.8

Latitud de (º)

21-Dec-2011 11:28:47 - 21-Dec-2011 17:29:11

21-Dec-2011 07:08:32 - 21-Dec-2011 11:28:21 40.8

D Deccem mb ber 20 0th-21 1stt (2 201 11)

Variabilityy of methane concentrations in the air blowing g over the Ebro Delta can be attributed both to the influence of the daily cycle (in metabolism or/and in air stability) and of the flooding stage. stage Patchiness can be attributed also to the size of the diff different t rice i paddies. ddi At Atmospheric h i methane values obtained after the dry period are similar to the planet background. g

Wi d influence. Wind i fl

The Ebro River valley channelize the winds coming from an Atlantic source. The RPSI (Restricted Potential Surface Influence) for January helps to explain the Mediterranean sea strong influence for the low values of methane over TAN (La Tancada Lagoon). Lagoon)

< 1880 40.6 06 0.6

0 65 0.65

07 0.7 Longitude (º)

0 75 0.75

08 0.8

Sunset /3 European Geosciences E G i Union U i General Assembly 2012 Vienna | Austria | 22 – 27 April p 2012

EGU 2012 ClimaDat  

poster EGU 2012 ClimaDat

EGU 2012 ClimaDat  

poster EGU 2012 ClimaDat

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