Impacts of large-scale drought and deluge on phenology and vegetation productivity in Southeastern...

Impacts of large-scale drought and deluge on phenology and vegetation

productivity in Southeastern Australia

Xuanlong Ma1, Alfredo Huete1, Susan Moran2, Guillermo Ponce-Campos2, Derek Eamus3

1 Plant Functional Biology & Climate Change ClusterUniversity of Technology Sydney

2 Southwest Watershed Research Centre,USDA Agriculture Research Service

3 School of Life Sciences, University of Technology Sydney

6 October 2015 @ Kusadasi, Turkey

Xuanlong Ma [email protected] 1

International Conference on Phenology Impact of Climate Extremes on Phenology

MOTIVATION



IN THE NEWS

Lake Hume (NSW), 2007

Credit:Tim

J Keegan

Xuanlong Ma [email protected]

Credit: Epoc Tinm

es

Stockman Gordon Litchfield at Leigh Creek (SA), 2006

33


Drought had significant impacts, including dramatic reduction in agricultural

production, reduced water availability for industrial and civil consumptions, increased forest die-back and bushfire (Sempel et al., 2010).



There is an increasing trend in the frequency and spatial extent of extreme

climate events around globe and in Australia, yet the impacts of these extreme climate on

ecosystem function remains uncertain.



Vegetation phenology and primary productivity represent key functions of an ecosystem,

potential changes in phenology and primary productivity under climate change will have

great implications to regional & global climate and biogeochemical cycles.



Phenology is the study of life cycles of flora and fauna and their interactions

with seasonal and inter-annual variations in climate and other factors.



Phenology is an integrative indicator of vegetation

responses to climate variability and change.



Vegetation phenology and primary productivity together represent key functions of an

ecosystem.



Therefore, understanding their relationships with environment is of great importance in global change studies that

aim to predict how ecosystem function will be affected by future climate changes.



Remote Sensing uses satellites to track seasonal changes in

vegetation activity on regional, continental, and global scales.



Remote sensing provide unparalleled way for detection and mapping vegetation phenological and functional responses to climate over broad-

scales, which complement the restricted coverage afforded by ground-based plots

observations.



The objective of this study is to investigate the shifts in

phenology and vegetation productivity under climatic

extremes.



DATA & METHOD



Southeastern Australia (SEA)

Land cover map of the SEA


Ma et al. (2015) JGR-Biogeosciences, in press


1.3 million km2

Southeastern Australia (SEA)

Land cover map of the SEA


Martin WellsBroken Hill

Yanco

TumbarumbaWarracknabeal

16

Chowilla



1.3 million km2

Satellite Data• Moderate Resolution Imaging

Spectroradiometer (MODIS) onboard NASA’s Terra satellite;

• Enhanced Vegetation Index (EVI);

• MOD13C1, 16-day, 0.05° resolution;

• 2000-2014;

• Quality Control (QC) applied.





Wavelength (microns)

Refl

ecta

nce




Refl

ecta

nce



Vegetation Index is based on the contrast between the reflectances at

NIR region and VIS region.


Refl

ecta

nce

Standardised Precipitation-Evapotranspiration Index (SPEI)

• SPEI is a multi-scaler drought index which takes into account both precipitation (P) and potential evapotranspiration (PET) in determine the drought severity (Vicente-Serrano et al., 2011);

• SPEI reflect the cumulative effect of the imbalance between atmospheric supply (P) and demand (PET);



Phenological Metrics ExtractionSeasonal maximum EVI

Prior Season Minimum EVI

10%

After Season Minimum EVI

10%

Soil background EVI = 0.08(yellow shaded area)

Annual integrated EVI (iEVI)(green shaded area)

SGS

PGS

EGSLGS●

Warracknabeal (Cropland)

0.0

0.1

0.2

0.3

0.4

0.5

Feb−2003 Apr−2003 Jun−2003 Aug−2003 Oct−2003 Dec−2003Date

EVI




RESULTS



First, we show the hydroclimatic impacts on seasonality of

vegetation growth.




(a)

(b)

(c)

(d)

(e)

(f)

Tumbarumba (Wet sclerophyll forest)

Yanco (Pasture)

Chowilla (Mallee woodland)

Warracknabeal (Wheat cropland)

Broken Hill (Hummock grassland)

Martins Wells (Acacia shrublands)

−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2

Sep−2000 Mar−2002 Sep−2003 Mar−2005 Sep−2006 Mar−2008 Sep−2009 Mar−2011 Sep−2012Date

EVI sd

or S

PEI

SPEI Dry Wet EVI

●

●

● ●

●

●

●●

●

●

●

●

●

●

●

●●

●

●●

●

●

●●

●

●

●●

●●

●● ●

●

●

●

●

● ●

●

●

●

●

●

●

●

● ●

●

●

●● ●

●●

●●

● ● ●●

● ● ●

● ● ● ● ●● ● ● ●

● ● ● ● ●

●

●

●

●

●●

● ●

●

●

●

●

● ●

●

●

●

●

●●

●

●

●

●

●

●●

●

●

● ●

●●

●

●●

●●●

●

●

● ●● ● ●

●

● ●●

●

●

●

●

● ●

● ●

●

●

● ● ● ● ● ● ● ● ● ● ● ●●

● ● ●● ●

●● ● ● ●

●● ● ●

● ● ● ● ● ●●

●

●

●

●

●

● ●

●

●

●

● ●

● ● ● ● ● ● ●●

● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●

●

●

●

●

●

●●

●

●● ● ●

● ● ●●

●

●● ●

●

●

● ●● ● ● ●

●

●●

● ●● ●

● ● ●● ●

●●

●● ●

●

●●

●

● ●

● ●

●

●

●

●● ●

●

●

●

●

●

●

●

●

●


Yanco (Pasture)





0.30

0.35

0.40

0.45

0.2

0.3

0.4

0.5

0.14

0.16

0.18

0.20

0.1

0.2

0.3

0.4

0.5

0.08

0.10

0.12

0.14

0.16

0.08

0.10

0.12

0.14

Jan Apr Jul OctDate

EVI M

OD

IS

● ●2002 (Drought) 2010 (Wet)

(a)

(b)

(c)

(d)

(e)

(f)


Yanco (Pasture)





−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2


EVI sd

or S

PEI

SPEI Dry Wet EVI

●

●

● ●

●

●

●●

●

●

●

●

●

●

●

●●

●

●●

●

●

●●

●

●

●●

●●

●● ●

●

●

●

●

● ●

●

●

●

●

●

●

●

● ●

●

●

●● ●

●●

●●

● ● ●●

● ● ●

● ● ● ● ●● ● ● ●

● ● ● ● ●

●

●

●

●

●●

● ●

●

●

●

●

● ●

●

●

●

●

●●

●

●

●

●

●

●●

●

●

● ●

●●

●

●●

●●●

●

●

● ●● ● ●

●

● ●●

●

●

●

●

● ●

● ●

●

●

● ● ● ● ● ● ● ● ● ● ● ●●

● ● ●● ●

●● ● ● ●

●● ● ●

● ● ● ● ● ●●

●

●

●

●

●

● ●

●

●

●

● ●

● ● ● ● ● ● ●●

● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●

●

●

●

●

●

●●

●

●● ● ●

● ● ●●

●

●● ●

●

●

● ●● ● ● ●

●

●●

● ●● ●

● ● ●● ●

●●

●● ●

●

●●

●

● ●

● ●

●

●

●

●● ●

●

●

●

●

●

●

●

●

●


Yanco (Pasture)





0.30

0.35

0.40

0.45

0.2

0.3

0.4

0.5

0.14

0.16

0.18

0.20

0.1

0.2

0.3

0.4

0.5

0.08

0.10

0.12

0.14

0.16

0.08

0.10

0.12

0.14

Jan Apr Jul OctDate

EVI M

OD

IS

● ●2002 (Drought) 2010 (Wet)

Seasonal and inter-annual variations in EVI and SPEI at local sites, 2000-2013

2525

All sites experienced severe and protracted drought condition throughout 2002 and 2003, as indicated by consecutive negative SPEI lasted for 9 - 14 monthsMa et al. (2015) JGR-Biogeosciences, in press


Second, we show the biogeographical patterns in vegetation phenology and productivity across drought and wet

years




SPEI

LGS (days)

iEVISD

27

In 2002, 87% areas of the SEA experienced drought impact, 76% areas experienced wet condition during the 2010




SPEI

LGS (days)

iEVISD

28


Within the areas that phenology was detected during both 2002 and 2010, there was an increasing trend in LGS over

70% areas of the SEA in the wet year.




SPEI

LGS (days)

iEVISD

29

Region-wide averaged productivity was reduced by 21% in the 2002 drought year and was increased by 20% in the

2010 wet year relative to 2000-2013 average.


Within the areas that phenology was detected during both 2002 and 2010, there was an increasing trend in LGS over

70% areas of the SEA in the wet year.



Quite dramatically, we found drought resulted in widespread reduction or

collapse in seasonality, associated with no detectable phenology over vast

drylands ecosystems.




2002 drought year

2010 wet year

2002 drought year

2010 wet year

EVI

32




2002 drought year

2010 wet year

2002 drought year

2010 wet year

EVI

33



Length of greening season > 6 months in normal or wet year


2002 drought year

2010 wet year

2002 drought year

2010 wet year

EVI

34



Length of greening season = 0 day in drought year

Length of greening season > 6 months in normal or wet year

DISCUSSIONS



First…



Phenology: the study of periodic plant and animal life

cycle events.



In temperate ecosystems, phenology profile as observed from satellite sensors normally

looks like…


Trends in Environmental Research Series (TIERS) 8 April 2015

3838



Harvard Forest, MA, USA, deciduous broadleaf forest Fisher & Mustad, 2007

Hmimina et al., 2013


3939




Fontainebleau, France, deciduous broadleaf forest Hmimina et al., 2013


4040




Fontainebleau, France, deciduous broadleaf forest Hmimina et al., 2013

Darwin, NT, Australia, tropical savanna Ma et al., 2013

4141


However, we found under highly variable climate, such as in Australia, phenology profile

looks like…




(a)

(b)

(c)

(d)

(e)

(f)


Yanco (Pasture)





−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2


EVI sd

or S

PEI

SPEI Dry Wet EVI

●

●

● ●

●

●

●●

●

●

●

●

●

●

●

●●

●

●●

●

●

●●

●

●

●●

●●

●● ●

●

●

●

●

● ●

●

●

●

●

●

●

●

● ●

●

●

●● ●

●●

●●

● ● ●●

● ● ●

● ● ● ● ●● ● ● ●

● ● ● ● ●

●

●

●

●

●●

● ●

●

●

●

●

● ●

●

●

●

●

●●

●

●

●

●

●

●●

●

●

● ●

●●

●

●●

●●●

●

●

● ●● ● ●

●

● ●●

●

●

●

●

● ●

● ●

●

●

● ● ● ● ● ● ● ● ● ● ● ●●

● ● ●● ●

●● ● ● ●

●● ● ●

● ● ● ● ● ●●

●

●

●

●

●

● ●

●

●

●

● ●

● ● ● ● ● ● ●●

● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●

●

●

●

●

●

●●

●

●● ● ●

● ● ●●

●

●● ●

●

●

● ●● ● ● ●

●

●●

● ●● ●

● ● ●● ●

●●

●● ●

●

●●

●

● ●

● ●

●

●

●

●● ●

●

●

●

●

●

●

●

●

●


Yanco (Pasture)





0.30

0.35

0.40

0.45

0.2

0.3

0.4

0.5

0.14

0.16

0.18

0.20

0.1

0.2

0.3

0.4

0.5

0.08

0.10

0.12

0.14

0.16

0.08

0.10

0.12

0.14

Jan Apr Jul OctDate

EVI M

OD

IS

● ●2002 (Drought) 2010 (Wet)

(a)

(b)

(c)

(d)

(e)

(f)


Yanco (Pasture)





−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2


EVI sd

or S

PEI

SPEI Dry Wet EVI

●

●

● ●

●

●

●●

●

●

●

●

●

●

●

●●

●

●●

●

●

●●

●

●

●●

●●

●● ●

●

●

●

●

● ●

●

●

●

●

●

●

●

● ●

●

●

●● ●

●●

●●

● ● ●●

● ● ●

● ● ● ● ●● ● ● ●

● ● ● ● ●

●

●

●

●

●●

● ●

●

●

●

●

● ●

●

●

●

●

●●

●

●

●

●

●

●●

●

●

● ●

●●

●

●●

●●●

●

●

● ●● ● ●

●

● ●●

●

●

●

●

● ●

● ●

●

●

● ● ● ● ● ● ● ● ● ● ● ●●

● ● ●● ●

●● ● ● ●

●● ● ●

● ● ● ● ● ●●

●

●

●

●

●

● ●

●

●

●

● ●

● ● ● ● ● ● ●●

● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●

●

●

●

●

●

●●

●

●● ● ●

● ● ●●

●

●● ●

●

●

● ●● ● ● ●

●

●●

● ●● ●

● ● ●● ●

●●

●● ●

●

●●

●

● ●

● ●

●

●

●

●● ●

●

●

●

●

●

●

●

●

●


Yanco (Pasture)





0.30

0.35

0.40

0.45

0.2

0.3

0.4

0.5

0.14

0.16

0.18

0.20

0.1

0.2

0.3

0.4

0.5

0.08

0.10

0.12

0.14

0.16

0.08

0.10

0.12

0.14

Jan Apr Jul OctDate

EVI M

OD

IS

● ●2002 (Drought) 2010 (Wet)

(a)

(b)

(c)

(d)

(e)

(f)


Yanco (Pasture)





−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2


EVI sd

or S

PEI

SPEI Dry Wet EVI

●

●

● ●

●

●

●●

●

●

●

●

●

●

●

●●

●

●●

●

●

●●

●

●

●●

●●

●● ●

●

●

●

●

● ●

●

●

●

●

●

●

●

● ●

●

●

●● ●

●●

●●

● ● ●●

● ● ●

● ● ● ● ●● ● ● ●

● ● ● ● ●

●

●

●

●

●●

● ●

●

●

●

●

● ●

●

●

●

●

●●

●

●

●

●

●

●●

●

●

● ●

●●

●

●●

●●●

●

●

● ●● ● ●

●

● ●●

●

●

●

●

● ●

● ●

●

●

● ● ● ● ● ● ● ● ● ● ● ●●

● ● ●● ●

●● ● ● ●

●● ● ●

● ● ● ● ● ●●

●

●

●

●

●

● ●

●

●

●

● ●

● ● ● ● ● ● ●●

● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●

●

●

●

●

●

●●

●

●● ● ●

● ● ●●

●

●● ●

●

●

● ●● ● ● ●

●

●●

● ●● ●

● ● ●● ●

●●

●● ●

●

●●

●

● ●

● ●

●

●

●

●● ●

●

●

●

●

●

●

●

●

●


Yanco (Pasture)





0.30

0.35

0.40

0.45

0.2

0.3

0.4

0.5

0.14

0.16

0.18

0.20

0.1

0.2

0.3

0.4

0.5

0.08

0.10

0.12

0.14

0.16

0.08

0.10

0.12

0.14

Jan Apr Jul OctDate

EVI M

OD

IS

● ●2002 (Drought) 2010 (Wet)

(a)

(b)

(c)

(d)

(e)

(f)


Yanco (Pasture)





−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2


EVI sd

or S

PEI

SPEI Dry Wet EVI

●

●

● ●

●

●

●●

●

●

●

●

●

●

●

●●

●

●●

●

●

●●

●

●

●●

●●

●● ●

●

●

●

●

● ●

●

●

●

●

●

●

●

● ●

●

●

●● ●

●●

●●

● ● ●●

● ● ●

● ● ● ● ●● ● ● ●

● ● ● ● ●

●

●

●

●

●●

● ●

●

●

●

●

● ●

●

●

●

●

●●

●

●

●

●

●

●●

●

●

● ●

●●

●

●●

●●●

●

●

● ●● ● ●

●

● ●●

●

●

●

●

● ●

● ●

●

●

● ● ● ● ● ● ● ● ● ● ● ●●

● ● ●● ●

●● ● ● ●

●● ● ●

● ● ● ● ● ●●

●

●

●

●

●

● ●

●

●

●

● ●

● ● ● ● ● ● ●●

● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●

●

●

●

●

●

●●

●

●● ● ●

● ● ●●

●

●● ●

●

●

● ●● ● ● ●

●

●●

● ●● ●

● ● ●● ●

●●

●● ●

●

●●

●

● ●

● ●

●

●

●

●● ●

●

●

●

●

●

●

●

●

●


Yanco (Pasture)





0.30

0.35

0.40

0.45

0.2

0.3

0.4

0.5

0.14

0.16

0.18

0.20

0.1

0.2

0.3

0.4

0.5

0.08

0.10

0.12

0.14

0.16

0.08

0.10

0.12

0.14

Jan Apr Jul OctDate

EVI M

OD

IS

● ●2002 (Drought) 2010 (Wet)

4343




(a)

(b)

(c)

(d)

(e)

(f)


Yanco (Pasture)





−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2


EVI sd

or S

PEI

SPEI Dry Wet EVI

●

●

● ●

●

●

●●

●

●

●

●

●

●

●

●●

●

●●

●

●

●●

●

●

●●

●●

●● ●

●

●

●

●

● ●

●

●

●

●

●

●

●

● ●

●

●

●● ●

●●

●●

● ● ●●

● ● ●

● ● ● ● ●● ● ● ●

● ● ● ● ●

●

●

●

●

●●

● ●

●

●

●

●

● ●

●

●

●

●

●●

●

●

●

●

●

●●

●

●

● ●

●●

●

●●

●●●

●

●

● ●● ● ●

●

● ●●

●

●

●

●

● ●

● ●

●

●

● ● ● ● ● ● ● ● ● ● ● ●●

● ● ●● ●

●● ● ● ●

●● ● ●

● ● ● ● ● ●●

●

●

●

●

●

● ●

●

●

●

● ●

● ● ● ● ● ● ●●

● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●

●

●

●

●

●

●●

●

●● ● ●

● ● ●●

●

●● ●

●

●

● ●● ● ● ●

●

●●

● ●● ●

● ● ●● ●

●●

●● ●

●

●●

●

● ●

● ●

●

●

●

●● ●

●

●

●

●

●

●

●

●

●


Yanco (Pasture)





0.30

0.35

0.40

0.45

0.2

0.3

0.4

0.5

0.14

0.16

0.18

0.20

0.1

0.2

0.3

0.4

0.5

0.08

0.10

0.12

0.14

0.16

0.08

0.10

0.12

0.14

Jan Apr Jul OctDate

EVI M

OD

IS

● ●2002 (Drought) 2010 (Wet)

(a)

(b)

(c)

(d)

(e)

(f)


Yanco (Pasture)





−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2


EVI sd

or S

PEI

SPEI Dry Wet EVI

●

●

● ●

●

●

●●

●

●

●

●

●

●

●

●●

●

●●

●

●

●●

●

●

●●

●●

●● ●

●

●

●

●

● ●

●

●

●

●

●

●

●

● ●

●

●

●● ●

●●

●●

● ● ●●

● ● ●

● ● ● ● ●● ● ● ●

● ● ● ● ●

●

●

●

●

●●

● ●

●

●

●

●

● ●

●

●

●

●

●●

●

●

●

●

●

●●

●

●

● ●

●●

●

●●

●●●

●

●

● ●● ● ●

●

● ●●

●

●

●

●

● ●

● ●

●

●

● ● ● ● ● ● ● ● ● ● ● ●●

● ● ●● ●

●● ● ● ●

●● ● ●

● ● ● ● ● ●●

●

●

●

●

●

● ●

●

●

●

● ●

● ● ● ● ● ● ●●

● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●

●

●

●

●

●

●●

●

●● ● ●

● ● ●●

●

●● ●

●

●

● ●● ● ● ●

●

●●

● ●● ●

● ● ●● ●

●●

●● ●

●

●●

●

● ●

● ●

●

●

●

●● ●

●

●

●

●

●

●

●

●

●


Yanco (Pasture)





0.30

0.35

0.40

0.45

0.2

0.3

0.4

0.5

0.14

0.16

0.18

0.20

0.1

0.2

0.3

0.4

0.5

0.08

0.10

0.12

0.14

0.16

0.08

0.10

0.12

0.14

Jan Apr Jul OctDate

EVI M

OD

IS

● ●2002 (Drought) 2010 (Wet)

(a)

(b)

(c)

(d)

(e)

(f)


Yanco (Pasture)





−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2


EVI sd

or S

PEI

SPEI Dry Wet EVI

●

●

● ●

●

●

●●

●

●

●

●

●

●

●

●●

●

●●

●

●

●●

●

●

●●

●●

●● ●

●

●

●

●

● ●

●

●

●

●

●

●

●

● ●

●

●

●● ●

●●

●●

● ● ●●

● ● ●

● ● ● ● ●● ● ● ●

● ● ● ● ●

●

●

●

●

●●

● ●

●

●

●

●

● ●

●

●

●

●

●●

●

●

●

●

●

●●

●

●

● ●

●●

●

●●

●●●

●

●

● ●● ● ●

●

● ●●

●

●

●

●

● ●

● ●

●

●

● ● ● ● ● ● ● ● ● ● ● ●●

● ● ●● ●

●● ● ● ●

●● ● ●

● ● ● ● ● ●●

●

●

●

●

●

● ●

●

●

●

● ●

● ● ● ● ● ● ●●

● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●

●

●

●

●

●

●●

●

●● ● ●

● ● ●●

●

●● ●

●

●

● ●● ● ● ●

●

●●

● ●● ●

● ● ●● ●

●●

●● ●

●

●●

●

● ●

● ●

●

●

●

●● ●

●

●

●

●

●

●

●

●

●


Yanco (Pasture)





0.30

0.35

0.40

0.45

0.2

0.3

0.4

0.5

0.14

0.16

0.18

0.20

0.1

0.2

0.3

0.4

0.5

0.08

0.10

0.12

0.14

0.16

0.08

0.10

0.12

0.14

Jan Apr Jul OctDate

EVI M

OD

IS

● ●2002 (Drought) 2010 (Wet)

(a)

(b)

(c)

(d)

(e)

(f)


Yanco (Pasture)





−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2


EVI sd

or S

PEI

SPEI Dry Wet EVI

●

●

● ●

●

●

●●

●

●

●

●

●

●

●

●●

●

●●

●

●

●●

●

●

●●

●●

●● ●

●

●

●

●

● ●

●

●

●

●

●

●

●

● ●

●

●

●● ●

●●

●●

● ● ●●

● ● ●

● ● ● ● ●● ● ● ●

● ● ● ● ●

●

●

●

●

●●

● ●

●

●

●

●

● ●

●

●

●

●

●●

●

●

●

●

●

●●

●

●

● ●

●●

●

●●

●●●

●

●

● ●● ● ●

●

● ●●

●

●

●

●

● ●

● ●

●

●

● ● ● ● ● ● ● ● ● ● ● ●●

● ● ●● ●

●● ● ● ●

●● ● ●

● ● ● ● ● ●●

●

●

●

●

●

● ●

●

●

●

● ●

● ● ● ● ● ● ●●

● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●

●

●

●

●

●

●●

●

●● ● ●

● ● ●●

●

●● ●

●

●

● ●● ● ● ●

●

●●

● ●● ●

● ● ●● ●

●●

●● ●

●

●●

●

● ●

● ●

●

●

●

●● ●

●

●

●

●

●

●

●

●

●


Yanco (Pasture)





0.30

0.35

0.40

0.45

0.2

0.3

0.4

0.5

0.14

0.16

0.18

0.20

0.1

0.2

0.3

0.4

0.5

0.08

0.10

0.12

0.14

0.16

0.08

0.10

0.12

0.14

Jan Apr Jul OctDate

EVI M

OD

IS

● ●2002 (Drought) 2010 (Wet)

Yanco, NSW (Pasture)

Warracknabeal, VIC (Wheat crop)

Broken Hill, NSW (Hummock grass)

Martin Wells, SA (Acacia shrubland)

Red: 2002 Blue: 2010

4444



Finding #1



Phenology is not repeated event, at least for Australia’s

dryland ecosystems.



46

Trends in Environmental Research Series (TIERS) Impact of Climate Extremes on Terrestrial Ecosystems

46


Drought resulted in widespread reductions or collapse in the normal patterns of seasonality such that in many cases there was no detectable

phenological cycle during drought years.



47


47


Implication of finding #1



48


48


The direction of the gradual shifting in ecosystem function and structure as induced by

global change (e.g., warming and CO2 fertilisation effect) in a long-run might be

suddenly altered, or even reversed direction, by short-term extreme climatic events.



49


49


Our findings highlight the need for models to explicitly take into account

climate-induced abrupt shifts in phenology and productivity for

predicting future ecosystem states, particularly in global semi-arid and arid regions where climate is highly

variable and vegetation growth is not or less limited by temperature but rather limited by water-availability.



50


50


Second…



51


51


Agricultural ecosystems, including cropland and

pastures, are important…



52


52


However, we found…



53


53



(a)

(b)

(c)

(d)

(e)

(f)


Yanco (Pasture)





−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2


EVI sd

or S

PEI

SPEI Dry Wet EVI

●

●

● ●

●

●

●●

●

●

●

●

●

●

●

●●

●

●●

●

●

●●

●

●

●●

●●

●● ●

●

●

●

●

● ●

●

●

●

●

●

●

●

● ●

●

●

●● ●

●●

●●

● ● ●●

● ● ●

● ● ● ● ●● ● ● ●

● ● ● ● ●

●

●

●

●

●●

● ●

●

●

●

●

● ●

●

●

●

●

●●

●

●

●

●

●

●●

●

●

● ●

●●

●

●●

●●●

●

●

● ●● ● ●

●

● ●●

●

●

●

●

● ●

● ●

●

●

● ● ● ● ● ● ● ● ● ● ● ●●

● ● ●● ●

●● ● ● ●

●● ● ●

● ● ● ● ● ●●

●

●

●

●

●

● ●

●

●

●

● ●

● ● ● ● ● ● ●●

● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●

●

●

●

●

●

●●

●

●● ● ●

● ● ●●

●

●● ●

●

●

● ●● ● ● ●

●

●●

● ●● ●

● ● ●● ●

●●

●● ●

●

●●

●

● ●

● ●

●

●

●

●● ●

●

●

●

●

●

●

●

●

●


Yanco (Pasture)





0.30

0.35

0.40

0.45

0.2

0.3

0.4

0.5

0.14

0.16

0.18

0.20

0.1

0.2

0.3

0.4

0.5

0.08

0.10

0.12

0.14

0.16

0.08

0.10

0.12

0.14

Jan Apr Jul OctDate

EVI M

OD

IS

● ●2002 (Drought) 2010 (Wet)

(a)

(b)

(c)

(d)

(e)

(f)


Yanco (Pasture)





−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2


EVI sd

or S

PEI

SPEI Dry Wet EVI

●

●

● ●

●

●

●●

●

●

●

●

●

●

●

●●

●

●●

●

●

●●

●

●

●●

●●

●● ●

●

●

●

●

● ●

●

●

●

●

●

●

●

● ●

●

●

●● ●

●●

●●

● ● ●●

● ● ●

● ● ● ● ●● ● ● ●

● ● ● ● ●

●

●

●

●

●●

● ●

●

●

●

●

● ●

●

●

●

●

●●

●

●

●

●

●

●●

●

●

● ●

●●

●

●●

●●●

●

●

● ●● ● ●

●

● ●●

●

●

●

●

● ●

● ●

●

●

● ● ● ● ● ● ● ● ● ● ● ●●

● ● ●● ●

●● ● ● ●

●● ● ●

● ● ● ● ● ●●

●

●

●

●

●

● ●

●

●

●

● ●

● ● ● ● ● ● ●●

● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●

●

●

●

●

●

●●

●

●● ● ●

● ● ●●

●

●● ●

●

●

● ●● ● ● ●

●

●●

● ●● ●

● ● ●● ●

●●

●● ●

●

●●

●

● ●

● ●

●

●

●

●● ●

●

●

●

●

●

●

●

●

●


Yanco (Pasture)





0.30

0.35

0.40

0.45

0.2

0.3

0.4

0.5

0.14

0.16

0.18

0.20

0.1

0.2

0.3

0.4

0.5

0.08

0.10

0.12

0.14

0.16

0.08

0.10

0.12

0.14

Jan Apr Jul OctDate

EVI M

OD

IS

● ●2002 (Drought) 2010 (Wet)

Red: 2002 Blue: 2010

Victoria wheat belt


54


54

Yanco

Warracknabeal




(a)

(b)

(c)

(d)

(e)

(f)


Yanco (Pasture)





−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2


EVI sd

or S

PEI

SPEI Dry Wet EVI

●

●

● ●

●

●

●●

●

●

●

●

●

●

●

●●

●

●●

●

●

●●

●

●

●●

●●

●● ●

●

●

●

●

● ●

●

●

●

●

●

●

●

● ●

●

●

●● ●

●●

●●

● ● ●●

● ● ●

● ● ● ● ●● ● ● ●

● ● ● ● ●

●

●

●

●

●●

● ●

●

●

●

●

● ●

●

●

●

●

●●

●

●

●

●

●

●●

●

●

● ●

●●

●

●●

●●●

●

●

● ●● ● ●

●

● ●●

●

●

●

●

● ●

● ●

●

●

● ● ● ● ● ● ● ● ● ● ● ●●

● ● ●● ●

●● ● ● ●

●● ● ●

● ● ● ● ● ●●

●

●

●

●

●

● ●

●

●

●

● ●

● ● ● ● ● ● ●●

● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●

●

●

●

●

●

●●

●

●● ● ●

● ● ●●

●

●● ●

●

●

● ●● ● ● ●

●

●●

● ●● ●

● ● ●● ●

●●

●● ●

●

●●

●

● ●

● ●

●

●

●

●● ●

●

●

●

●

●

●

●

●

●


Yanco (Pasture)





0.30

0.35

0.40

0.45

0.2

0.3

0.4

0.5

0.14

0.16

0.18

0.20

0.1

0.2

0.3

0.4

0.5

0.08

0.10

0.12

0.14

0.16

0.08

0.10

0.12

0.14

Jan Apr Jul OctDate

EVI M

OD

IS

● ●2002 (Drought) 2010 (Wet)

(a)

(b)

(c)

(d)

(e)

(f)


Yanco (Pasture)





−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2

−2

0

2


EVI sd

or S

PEI

SPEI Dry Wet EVI

●

●

● ●

●

●

●●

●

●

●

●

●

●

●

●●

●

●●

●

●

●●

●

●

●●

●●

●● ●

●

●

●

●

● ●

●

●

●

●

●

●

●

● ●

●

●

●● ●

●●

●●

● ● ●●

● ● ●

● ● ● ● ●● ● ● ●

● ● ● ● ●

●

●

●

●

●●

● ●

●

●

●

●

● ●

●

●

●

●

●●

●

●

●

●

●

●●

●

●

● ●

●●

●

●●

●●●

●

●

● ●● ● ●

●

● ●●

●

●

●

●

● ●

● ●

●

●

● ● ● ● ● ● ● ● ● ● ● ●●

● ● ●● ●

●● ● ● ●

●● ● ●

● ● ● ● ● ●●

●

●

●

●

●

● ●

●

●

●

● ●

● ● ● ● ● ● ●●

● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●

●

●

●

●

●

●●

●

●● ● ●

● ● ●●

●

●● ●

●

●

● ●● ● ● ●

●

●●

● ●● ●

● ● ●● ●

●●

●● ●

●

●●

●

● ●

● ●

●

●

●

●● ●

●

●

●

●

●

●

●

●

●


Yanco (Pasture)





0.30

0.35

0.40

0.45

0.2

0.3

0.4

0.5

0.14

0.16

0.18

0.20

0.1

0.2

0.3

0.4

0.5

0.08

0.10

0.12

0.14

0.16

0.08

0.10

0.12

0.14

Jan Apr Jul OctDate

EVI M

OD

IS

● ●2002 (Drought) 2010 (Wet)

Red: 2002 Blue: 2010

Victoria wheat belt “We want to see the Murray flow.” NSW farmer Gilbert Bain is harvesting

his withered wheat near Deniliquin.


55


55

Yanco

Warracknabeal




(a) (b) (c)

(d) (e) (f)

(g) (h) (i)

Rainfed Cropland Rainfed Pasture Tussock Grassland

Hummock Grassland Shrubland Closed Forest

Open Forest Open Woodland Woodland

0.0

0.5

1.0

1.5

0.0

0.5

1.0

1.5

012345

0

1

2

3

0

1

2

0.0

0.3

0.6

0.9

1.2

0.0

0.3

0.6

0.9

0

1

2

3

4

0.0

0.5

1.0

1.5

−2 0 2 −2 0 2 −2 0 2∆iEVIsd or ∆SPEI

Den

sity

iEVI SPEI

2002 − Mean 2010 − Mean

(a) (b) (c)

(d) (e) (f)

(g) (h) (i)




0.0

0.5

1.0

1.5

0.0

0.5

1.0

1.5

012345

0

1

2

3

0

1

2

0.0

0.3

0.6

0.9

1.2

0.0

0.3

0.6

0.9

0

1

2

3

4

0.0

0.5

1.0

1.5

−2 0 2 −2 0 2 −2 0 2∆iEVIsd or ∆SPEI

Den

sity

iEVI SPEI

2002 − Mean 2010 − Mean

(a) (b) (c)

(d) (e) (f)

(g) (h) (i)




0.0

0.5

1.0

1.5

0.0

0.5

1.0

1.5

012345

0

1

2

3

0

1

2

0.0

0.3

0.6

0.9

1.2

0.0

0.3

0.6

0.9

0

1

2

3

4

0.0

0.5

1.0

1.5

−2 0 2 −2 0 2 −2 0 2∆iEVIsd or ∆SPEI

Den

sity

iEVI SPEI

2002 − Mean 2010 − Mean

(a) (b) (c)

(d) (e) (f)

(g) (h) (i)




0.0

0.5

1.0

1.5

0.0

0.5

1.0

1.5

012345

0

1

2

3

0

1

2

0.0

0.3

0.6

0.9

1.2

0.0

0.3

0.6

0.9

0

1

2

3

4

0.0

0.5

1.0

1.5

−2 0 2 −2 0 2 −2 0 2∆iEVIsd or ∆SPEI

Den

sity

iEVI SPEI

2002 − Mean 2010 − Mean

(a) (b) (c)

(d) (e) (f)

(g) (h) (i)




0.0

0.5

1.0

1.5

0.0

0.5

1.0

1.5

012345

0

1

2

3

0

1

2

0.0

0.3

0.6

0.9

1.2

0.0

0.3

0.6

0.9

0

1

2

3

4

0.0

0.5

1.0

1.5

−2 0 2 −2 0 2 −2 0 2∆iEVIsd or ∆SPEI

Den

sity

iEVI SPEI

2002 − Mean 2010 − Mean

Red: 2002 Blue: 2010

Negative impact of drought was amplified by cropland


56


56




(a) (b) (c)

(d) (e) (f)

(g) (h) (i)




0.0

0.5

1.0

1.5

0.0

0.5

1.0

1.5

012345

0

1

2

3

0

1

2

0.0

0.3

0.6

0.9

1.2

0.0

0.3

0.6

0.9

0

1

2

3

4

0.0

0.5

1.0

1.5

−2 0 2 −2 0 2 −2 0 2∆iEVIsd or ∆SPEI

Den

sity

iEVI SPEI

2002 − Mean 2010 − Mean

(a) (b) (c)

(d) (e) (f)

(g) (h) (i)




0.0

0.5

1.0

1.5

0.0

0.5

1.0

1.5

012345

0

1

2

3

0

1

2

0.0

0.3

0.6

0.9

1.2

0.0

0.3

0.6

0.9

0

1

2

3

4

0.0

0.5

1.0

1.5

−2 0 2 −2 0 2 −2 0 2∆iEVIsd or ∆SPEI

Den

sity

iEVI SPEI

2002 − Mean 2010 − Mean

(a) (b) (c)

(d) (e) (f)

(g) (h) (i)




0.0

0.5

1.0

1.5

0.0

0.5

1.0

1.5

012345

0

1

2

3

0

1

2

0.0

0.3

0.6

0.9

1.2

0.0

0.3

0.6

0.9

0

1

2

3

4

0.0

0.5

1.0

1.5

−2 0 2 −2 0 2 −2 0 2∆iEVIsd or ∆SPEI

Den

sity

iEVI SPEI

2002 − Mean 2010 − Mean

(a) (b) (c)

(d) (e) (f)

(g) (h) (i)




0.0

0.5

1.0

1.5

0.0

0.5

1.0

1.5

012345

0

1

2

3

0

1

2

0.0

0.3

0.6

0.9

1.2

0.0

0.3

0.6

0.9

0

1

2

3

4

0.0

0.5

1.0

1.5

−2 0 2 −2 0 2 −2 0 2∆iEVIsd or ∆SPEI

Den

sity

iEVI SPEI

2002 − Mean 2010 − Mean

(a) (b) (c)

(d) (e) (f)

(g) (h) (i)




0.0

0.5

1.0

1.5

0.0

0.5

1.0

1.5

012345

0

1

2

3

0

1

2

0.0

0.3

0.6

0.9

1.2

0.0

0.3

0.6

0.9

0

1

2

3

4

0.0

0.5

1.0

1.5

−2 0 2 −2 0 2 −2 0 2∆iEVIsd or ∆SPEI

Den

sity

iEVI SPEI

2002 − Mean 2010 − Mean

Red: 2002 Blue: 2010

Negative impact of drought was amplified by cropland


57


57

Native dryland vegetation buffered drought impact

very well Ma et al. (2015) JGR-Biogeosciences, in press


Finding #2:



58


58


SE Australia’s agricultural ecosystems, including cropland and

pastures, didn’t buffer drought impact as good as native

vegetations.



59


59


In a climate change perspective, predicted increases in drought

frequency and intensity will have great impact on Australia’s

agricultural ecosystems, resulted in a series of consequences, such as crop failures, forage loss, and

pasture degradation.



60


60


These pose concerns on their sustainable ability to support human livelihood and social

functioning, and suggested that improved management and

adaption strategies should be strengthened in these areas of

concerns.



61


61


Besides, our results highlighted the significant role of native vegetations,

particularly hummock grassland (spinifex) and shrubland (e.g., Acacia shrubland, or Mulga), in buffering the impacts of drought on regional carbon balance and subsequent feedback to

regional and global climate.



6262


For example, the positive anomaly in global land carbon sink in 2010-11 was largely driven by semi-arid ecosystems in Southern Hemisphere, with 60% of global

carbon uptake anomaly was attributed to Australia’s drylands ecosystems (Poulter et al., 2014).



6363


Summary



64


Summary



65


• We found dramatic impacts were exerted by drought and wet extremes on vegetation phenology & productivity, with abrupt change in phenology and productivity between dry and wet years.

• We found agricultural ecosystems did not buffer drought well, while native dryland ecosystems were quite resistant and resilient to hydroclimatic variations.

Summary



66


• We found dramatic impacts were exerted by drought and wet extremes on vegetation phenology & productivity, with abrupt change in phenology and productivity between dry and wet years.

• We found agricultural ecosystems did not buffer drought well, while native dryland ecosystems were quite resistant and resilient to hydroclimatic variations.

Thanks! Questions?


Trend in Environment ResearchTrends in Environmental Research Series (TIERS) Impact of Climate Extremes on Terrestrial Ecosystems

67


Murray-Darling National ParkPhoto Credit: Ignacio Palacios/Lonely Planet

Impacts of large-scale drought and deluge on phenology and vegetation productivity in Southeastern...

Science

Transcript of Impacts of large-scale drought and deluge on phenology and vegetation productivity in Southeastern...