Characterization of the Wine Grape Thermohydrological Conditions in the Tropical Brazilian ...

15 Pages·2015·5.72 MB·English

Hindawi Publishing Corporation
ISRN Agronomy
Volume 2014, Article ID 727123, 14 pages
http://dx.doi.org/10.1155/2014/727123
Research Article
Characterization of the Wine Grape
Thermohydrological Conditions in the Tropical Brazilian
Growing Region: Long-Term and Future Assessments
AntônioHeribertodeCastroTeixeira,1JorgeTonietto,2
GiulianoEliasPereira,2andFernandoBrazTangerinoHernandez3
1Embrapa,13070-115Campinas,SP,Brazil
2Embrapa,95700-000BentoGon¸calves,RS,Brazil
3Sa˜oPauloStateUniversity,15385-000IlhaSolteira,SP,Brazil
CorrespondenceshouldbeaddressedtoJorgeTonietto;[email protected]
Received12November2013;Accepted22December2013;Published10February2014
AcademicEditors:J.Hatfield,N.Hulugalle,andL.Mateos
Copyright©2014AntoˆnioHeribertodeCastroTeixeiraetal. This is an open access article distributed under the Creative
Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the
originalworkisproperlycited.
Overthelastyears,Brazilhasappearedamongthenewtropicalwineproducingcountries.Thejoinedeffectofrisingairtemperature
anddecreasingprecipitationmakesitimportanttoquantifythetrendofthethermohydrologicalconditionsofthecommercial
vineyards.Theaims ofthecurrentresearchweretoclassifyanddelimittheseconditionsforthewinemakingprocesses under
differenttimescenariosintheBrazilianNortheasternregion.Bioclimaticindicatorswereusedtogetherwithlong-termweatherdata
andprojectionsoftheIPCCemissionscenariosundersimulatedpruningdates.Theresultsshowedthatdecreasingofprecipitation
shouldbegoodforwineproductionwhenirrigationwaterisavailable,butrisingairtemperaturewillaffectthewinequalityand
stability mainly for pruning done from November to March. The best pruning periods are around May for any time scenario
considered. In general, more care should be taken for pruning happening in other periods of the year, regarding the effect of
increasingthermalconditionsonwinequality.Theclassificationanddelimitationdone,joinedwithotherecologicalcharacteristics,
areimportantforarationalplanningofthecommercialwineproductionexpansion,mainlyinsituationsofclimateandlanduse
changestogetherwithrisingwatercompetition.
1.Introduction Air temperature values lower than 10∘C will limit the
vineshootgrowth,inducingtheplantstoadormancyperiod
Long-term observations and models are showing pieces of in temperate climates [5]. The optimum thermal range is
∘
evidence of alterations in the climate system happening in considered between 25 and 30 C [6]. According to Huglin
severalplacesoftheworld,whichcanbeattributedtohuman andSchneider[7],undersituationsofairtemperaturehigher
∘ ∘
activities.These effects are mainlyconsequencesofchanges than25 C,netphotosynthesisdecreases.Above30 C,berry
intheatmosphericcompositionandhenceglobalaverageair size and weight are reduced, with the metabolic processes
∘
temperatureisprojectedtorisetogetherwithregionalvaria- dropping near 45 C [8]. Rising air temperature contributes
tionsinprecipitationpatterns[1,2]. to high sugar concentration in grapes, resulting in larger
Grapevine phenology, wine quality, and yield are very alcohol content in wines and lower acidity, increasing pH.
dependent on climate at regional, local, and microclimatic As consequences, the presence, intensity and quality of the
scales [3]. Regional climate has been the focus of climate aroma,colour,andwinestabilitymaybeaffectednegatively
changeimpactassessments.Atthelocallevel,theconsider- [9,10].
ations of grape site selection, cultural practices, and water Webbetal.[11]analysingairtemperaturerangesconclud-
managementareincreasing,beingveryimportantissuesfor ed that, by 2030 in Australia, there may be additional areas
potentialadaptationstoclimatechanges[4]. forgrowingsomegrapevarieties,but,overall,reductionsin
2 ISRNAgronomy
suitable areas are predicted by 2050 (between 27%, mid- ClimaticClassification(MCC)SystemproposedbyTonietto
warming, and 44%, high warming). However, in the USA, andCarbonneau[27]hasbeenusedundertemperateclimate
White et al. [12] showed that predictions based on average conditionsinEurope[28,29]andinSouthAmerica[30,31].
airtemperaturerangesalonemightunderestimatetheclimate However,themethodhasworkedwellconsideringasingle,
changesimpactsonviticulture. six-monthgrowingseasonperyearundertheseconditions.
According to Ganichot [13], the potential alcohol levels Over the last years, the Brazilian tropical region has
ofgrapesincreasedby2%(from9.7to22.7v/v%),whiletotal appearedamongthenewwineproducingareas.Withproper
aciditydecreasedfrom6to4gL−1H2SO4andpHincreased irrigation and cultural management practices, the farmers
from 3.0 to 3.3, across all grape cultivars between 1980 and canproducegrapesandcarryoutwinemakingatanytimeof
2001 in southern France. Jones [14] reviewed reports on theyear,allowingapotentialaverageofbetweentwotothree
increasedalcohollevelsinwinesfromAlsace,Australia,and vineyard-growing cycles per year, in accordance with and
Napa founding that 50% of their increases are attributed to dependingoneachvariety[19].Theriseoftheairtemperature
climatechanges. withaconsequentincreaseinaridityintheBrazilianNorth-
east region will affect the wine quality and water require-
Besides the direct effects of rising air temperature on
ments. The joined effect of rising water consumption and
vinephysiologyandgrapecomposition,thereareimportant
decreasingprecipitation,togetherwithrapidlandusechange,
secondary ones. Increased soil and water salinity is a phe-
makesitimportanttoquantifythevineyardthermohydrolog-
nomenonassociatedwithseveralsemiaridandaridregions
icaltrendsonalargescaletosubsidizewinemakingadapta-
relyingonirrigation[15,16].Thesejointeffectscanpromote
tionsandwaterproductivityimprovementsinthenearfuture.
highconcentrationsofNa,K,andClinwines[17].Risingair
∘ Theobjectiveofthisresearchwastocombinebioclimatic
temperatures (30 C) may increase suspended solid concen-
∘ indicators,togetherwithlong-termweatherdataandprojec-
trations, but Brix levels larger than 24 C Brix are likely not
tionsoftheIPCCA2andB2emissionscenariosfortheyears
due to photosynthesis and sugar transport from leaves and
2020,2050,and2080,toclassifyanddelimitthethermohy-
woods.Thesehighlevelscanbeattributedtoanincreaseof
drological conditions for the winemaking processes under
evapotranspiration(ET),asthewarmairclosetothecanopies
different pruning dates and time scenarios in the Brazilian
isoneoftheenergysourcesforthewaterfluxes[18].
Northeastern region. The modelling aims to subsidize the
Warmingconditionscandirectlyaffectthevineyardwater
rational expansion of wine grape crop and improvements
requirements,which,togetherwithprecipitationreductions,
on water productivity, while minimizing undesired climate
will lead to high levels of both aridity and irrigation water
changeeffectsonwinequalityandenvironmentaldamages.
demand[19].AccordingtoWebbetal.[20],theairtempera-
This information is very important in situations of rising
tureriseduringtheharvestperiodmayreduceberryquality
water competition by irrigated agriculture, natural vegeta-
throughhigherETrates.Apredictionofincreasingvineyard
tion, and nonagricultural sectors in the present and future
waterconsumptionup30%by2070,despite thechanges in
conditions.
precipitationpatterns,wasobservedinAustralia[21].
Jackson and Cherry [22] reported that high rainfall
2.MaterialsandMethods
amountsreducetheripeningcapacityofgrapes.Ontheother
hand,acertainlevelofwaterstressduringthisstageisfavour- Figure1 shows details of the Brazilian geographic regions,
ablefortheorganolepticwinequality[7].Dryweathermakes with states of the Northeast region and the location of the
irrigation technologies an important asset for controlling raingaugesandtheconventionalagrometeorologicalstations
water deficiencies and excesses and the need of vineyard used.
waterrequirementsquantification[19,21]. Theavailablemonthlytotalprecipitationdatawerefrom
According to Webb [23] the vineyard-growing season SUDENE (Superintendence of Development of the North-
precipitation amounts are predicted to decrease or increase east) referred to 1455 locations of rain gauges, while the
inAustralia,dependingupontheregion,whilethearidityis monthly mean air temperature data were from INMET
expectedtoriseinallareasby2030and2050.Generally,these (National Meteorological Institute) recorded in 75 conven-
predictions translate the need of a reduction in irrigation tionalstations.
water supply through increasing water productivity, which These weather data are long-term values for the period
maybeconsideredastheratiooftheactualyieldtothewater from 1961 to 1990, taken as the baseline conditions in this
consumption[24]. study and used for comparisons with the IPCC A2 and B2
Arangeofemissionscenarioshavebeendevelopedinthe emission scenarios for the projected years 2020, 2050, and
IntergovernmentalPanelonClimateChange(IPCC)Special 2080. In the stations with only precipitation data available,
ReportsonEmissionScenariosthatreflectwaysinwhichthe themonthlyairtemperature(𝑇 )valueswereestimated
month
worldmightdevelop[25]. fromthegeographiccoordinates[32].
A large number of climate models have classified wine- As the air temperature data is easier to be obtained for
makingregionsbyusingdifferentmethodologies(e.g.,Bon- thewholeBrazilianNortheastthantheothermeteorological
nardotetal.[26];ToniettoandCarbonneau[27]).Forther- parametersinvolvedinthewatervapourtransfer,theThorn-
mohydrological vineyard delimitation, aiming at grape and thwaite (TH) method, which needs only the monthly aver-
wine production, one can apply bioclimatic indices based ages (𝑇 ) as an input, was first applied to retrieve the
month
on the thermohydrological requirements. The Multicriteria monthly reference evapotranspiration (ETo). Available or
ISRNAgronomy 3
−72 −68 −64 −60 −56 −52 −48 −44 −40 −36 −32
4
0
−4 North
MA
CE RN
PB
−8 PI PE
Northeast AL
SE
−12 BA
Central West
−16
−20 Brazil Southeast
−24
N
South
−28
0 1000
−32
(km)
Figure1:BrazilianregionsandtheNortheasternstatesofMaranha˜o(MA),Piau´ı(PI),Ceara´(CE),RioGrandedoNorte(RN),Para´ıba(PB),
Pernambuco(PE),Alagoas(AL),Sergipe(SE),andBahia(BA),togetherwiththelocationsoftheraingaugesandconventionalagrometeor-
ologicalstations.
estimatedweatherdatafromtheconventionalstationswere months (VWRGS). Taking five 𝐾𝑐 modelled values from
usedtogetherwithastronomicalrelations[33]. DDac, and a base air temperature (𝑇𝑏) of 10∘C, zero being
Simultaneousmeasurementsofpotentialevapotranspira- the initial value for DDac and considering the accumu-
tion(ETp)inwinegrapecv.Syrahunderoptimalsoilmois- lated ones for the first, second, third, and fourth months,
tureconditions,togetherwithETobythePenman-Monteith the average crop coefficient (𝐾𝑐 ) was multiplied by EToGS
GS
(PM) method [34], allowed the acquirement of crop coeffi- togiveVWRGS:
cient(𝐾𝑐)alongacompletegrowingseason[35].Dailydata
ofsolarradiation,airtemperatureandrelativehumidity,and VWRGS =𝐾𝑐 EToGS. (2)
GS
wind speed from an automatic agrometeorological station
wereusedforthecalculationofETo. VWRGS togetherwiththemeantotalprecipitationfora
In the current research, a model based on the relation growingseason(𝑃GS)allowedthedevelopmentandapplica-
of𝐾𝑐 andtheaccumulateddegree days (DDac)wasusedto tionofavineyardwaterindicator(VWIGS)forthemoisture
retrieve ETp, considering the cv. Syrah as a reference [19], delimitationsintheBrazilianNortheast,varyingthepruning
afterapplyingregressionequationsforcalibratingEToTHinto dates:
EToPM throughout regression equations. Seven automatic 𝑃
agrometeorologicalstationsinthesemiaridconditionsofthe VWI = GS . (3)
GS VWR
BrazilianNortheastwereusedforthiscalibration: GS
𝐾𝑐 =𝑎GDac2+𝑏GDac+𝑐, (1) The indicator represented by (3) enables the character-
ization of the water component of the climate, taking into
where𝑎=−2×10−7,𝑏=4×10−4,and𝑐=0.54aretheregres- accounttheinputandoutputofwaterfromandtothevine-
sioncoefficientsvalidfortheBraziliansemiaridconditions, yards, indicating the potential moisture availability in their
with𝑅2 =0.80. rootzones.
ForthecalibrationofET0THintoET0PM,beforeusingthe VWIGSvaluesaround1.00implythefeasibilityforrainfed
modelrelating𝐾𝑐andDDac,theregressionequationsforthe winegrapecrop,whilethosemuchhigherindicateunsuitable
first and for the second semesters were applied separately, conditionsindependentlyofirrigationwateravailability,due
both presenting 𝑅2 around 0.70. Since the intention is to to problems of moisture excess. Low VWIGS values mean
applybioclimaticindicatorsforclassifyingwinegrapeareas naturalwaterdeficienciesandthedegreeofirrigationneeds
andnottohaveaccurateETmeasurements,thiscalibration accordingtothepruningdates.
processseemstobeplausibleconsideringtheabsenceofall Thefuturescenarioswereconsideredbyusingprecipita-
meteorologicalparametersnecessaryforPMequationinthe tionandairtemperaturedatafortheprojectedyearscantered
wholeBrazilianNortheastregion. on2020,2050,and2080fromIPCCreports[1,2]simulated
TheETpforonegrowingseason(GS)wasconsideredas by the model HadCM3 from the Hadley centre [36], which
the vineyard water requirements for an average GS of four was chosen because it was the one that best agreed with
4 ISRNAgronomy
∘
observed historical weather data among others tested in canseealargerareawiththosehigherthan24.0 C,forprun-
SouthAmerica[37]. inginOctober(Figure2(a)).
The baseline and projected weather data were interpo- Analysingthe𝑃 maps(Figure2(b)),duringthewettest
GS
lated in a Geographic Information System (GIS) environ- GS,Maranha˜o(MA)andtheNorthwesternsideofPiau´ı(PI)
ment, by the “movingaverage” method, and the thermohy- statearethemostproblematicareas,becauseoftheAmazon’s
drologicalmodelswereappliedtothegridsof𝑃GSand𝑇GS. climatic influences, with total averaged values higher than
Basic criteria for dividing the Northeastern region into 750mm.Whenthepruningoccursduringthedriestperiod,
fourclasses(C1,C2,C3,andC4)ofvineyardthermohydro- almost the whole Northeast Brazil shows 𝑃 long-term
GS
logical conditions were used. First, the VWIGS values were valuesbelow400mm,evenlowerthan150mminthecentral
consideredthemostimportantfactor,astheexcessivemois- andSouthwesternareasoftheregion.
tureisnotsuitableforthewinegrapecrop,independentlyif
Figure3showsthespatialvariationoftheVWRGSvalues
irrigatedornot.
forthereferencecv.Syrah,underdifferentpruningdatesand
WhenVWIGSvaluesarelowerorequalto2.00(classesC1 anaverageGSoffourmonths,basedonthelong-termdata
andC2),themoistureconditionsarethebest,becauseofless
from 1961 to 1990 (baseline conditions), in the Brazilian
plantdiseases,rootrespirationproblems,anddirectdamage
Northeastregion.
tothefruitspromotedbyexcessofprecipitation.Thesecon-
ditions will favour better quality of must and wine, where, ThepruningdateswithmaximumVW−R1GS valuesarein
September,whentheaverageis410mmGS ,whilethelow-
accordingtodatafromtheBrazilianGeographicalandSta-
est ones are found when they are in March, around
tistical Institute (IBGE), the commercial wine grapes are
−1
300mmGS .Accordingtothestandarddeviations(SD),the
concentratedintheBrazilianNortheasternregion.
smallestandthelargestspatialvariationsoccur,respectively,
Aswarmerconditionsaffectnegativelythewinequality,
−1
the most suitable areas in relation to moisture conditions forpruningdonefromMarchtoMay(SD=18mmGS )and
wereclassifiedaccordingtoa𝑇 thresholdof24∘C.C1areas betweenAugustandOctober(SD=23mmGS−1).
wereconsideredthosewith𝑇GSGbSelow24∘CandC2areasare Table1presentsthevariationofVWRGSforthereference
thoseabovethisvalue.Althoughthelatterclasshassuitable cv.Syrah,amongtheBrazilianNortheasternstates,consider-
naturalmoistureconditionsforirrigatedwinecrop,aslong ingthebaselineconditions(1961–1990)anddifferentpruning
as the air temperature increases above this threshold value, datesforafour-monthaverageGS.
the wine quality should be affected, contributing to high HighlightsareforPiau´ı(PI),Ceara´(CE),andRioGrande
levelsofalcohol,lowacidity,andlargepHvalues,becoming do Norte (RN) as the states with the largest vineyard water
unbalanced with instability for the phenolic and aromatic demands.ThehighestaveragevaluesarefoundinCeara´(CE),
composition. whilethelowestonesareforBahia(BA)state.Theextremesof
−1
InsituationsofVWIGSbeinghigherthan2.00,thegrow- VWRGSvaluesrepresentadailyrangefrom2.5to3.3mmd .
ing wine grape areas and yield are reduced, according to For the delimitation of the thermohydrological condi-
data from IBGE. A class with VWIGS higher than 2.00 and tionsofthereferencewinegrapecv.Syrah,consideringdif-
lowerorequalto4.00wasthenconsideredasanintermediary ferent pruning dates and an average four months GS, the
one; insofar the natural moisture increases, the yield and bioclimatic indicator VWIGS was first considered for the
winequalityshouldbeaffected,independentlyofthethermal baselineconditions(Figure4).
conditions. PruningdatesbetweenJuneandAugustpresentthelarg-
Areas and pruning dates inside the worst class, those est area of natural climate dryness conditions. Under these
having VWIGS higher than 4.00, should present the biggest circumstancestheVWIGS valuesarebelow0.50andtheSD
problemsingrapeyieldduetohighlevelsofnaturalhumidity between0.25and0.40.Ontheotherhand,VWIGSlargerthan
that compromise the grape sanity, enological potential, and 2.00andSDabove0.70occurinlargerareasforpruningdates
consequentlythewinequality.Thereisnocommercialwine fromDecembertoApril,mainlyintheNorthwesternsideof
grapecropreportedbytheIBGEundertheseconditionsin Maranha˜o(MA)state.
theBrazilianNortheasternstates. Table2presentstheaverageVWIGS valuesperstate,for
thewinegrapecv.Syrah,consideringdifferentpruningdates
3.Results alongtheyearandanaveragegrowingseasonoffourmonths,
intheBrazilianNortheast,byusingweatherdataforthebas-
3.1. Long-Term Vineyard Thermohydrological Conditions. elineconditions(1961–1990).
Figure2 shows the maps of the 𝑇GS long-term values, for, VWIGSvaluesaround2.00orhigherfortherainyperiod
respectively, the coldest and the hottest GS, with pruning are found in Maranha˜o (MA), Piau´ı (PI), and Ceara´ (CE)
dates in July and October (Figure2(a)), respectively, and states.Thelowestonesoccurduringthedriestpruningperi-
those of 𝑃 , for the wettest and the driest conditions,with ods, in Ceara´ (CE) and Rio Grande do Norte (RN), with
GS
pruningdatesinJanuaryandJune(Figure2(b)),respectively. averagesevenbellow0.10.
Thelowest𝑇 valuesoccuratthewintersolsticetimein Figure5showsthedelimitationoffourclasses,according
GS
the Southern hemisphere, while the highest ones are found tothethermohydrologicalconditionsforthebaselinecondi-
whentheSunisaroundthezenithpositionoverthecentral tions,consideringdifferentpruningdatesalongtheyear,the
partoftheBrazilianNortheasternregion.ForpruninginJuly, referencewinegrapecropcv.Syrah,andanaverageGSoffour
manypixelspresent𝑇 valueslowerthan22.0∘C,whileone months.
GS
ISRNAgronomy 5
35.0 1300
30.8 1040
26.6 780
July January
C) m)
∘T(GS P(mGS
22.4 520
18.2 260
October June
14.0 0
(a) (b)
Figure2:Mapsofthelong-termweathervalues(1961–1990)foranaveragewinegrapegrowingseasonoffourmonthsintheBrazilianNorth-
easternregion:(a)meanairtemperatureforthecoldestandthehottestconditions(𝑇 ),withpruningdates,respectively,inJulyandOctober
GS
and(b)totalprecipitation,forthewettestandthedriestconditions(𝑃 ),withpruningdates,respectively,inJanuaryandJune.
GS
Table1:Meanvaluesofthevineyardgrapewaterrequirements,cv.Syrah,fordifferentpruningdates,consideringanaveragegrowingseason
offourmonths(VWR )andthebaselineconditions(1961–1990)intheBrazilianNortheasternstatesofMaranha˜o(MA),Piau´ı(PI),Ceara´
GS
(CE),RioGrandedoNorte(RN),Para´ıba(PB),Pernambuco(PE),Alagoas(AL),Sergipe(SE),andBahia(BA).
VWR VWR VWR VWR VWR VWR VWR VWR VWR
Pruningdate GSMA GSPI GSCE GSRN GSPB GSPE GSAL GSSE GSBA
(mm) (mm) (mm) (mm) (mm) (mm) (mm) (mm) (mm)
January 278.6 312.9 327.0 336.2 319.2 319.2 318.3 331.4 311.2
February 271.2 304.0 313.2 323.8 306.1 304.9 306.7 321.5 301.4
March 269.5 298.0 309.0 316.0 297.6 294.3 295.2 308.3 288.6
April 287.7 308.8 324.9 325.1 307.8 302.0 300.9 311.5 295.0
May 319.0 329.0 348.2 341.4 324.3 316.6 312.3 320.4 312.0
June 352.5 358.3 375.0 363.1 348.0 341.0 332.5 336.4 336.5
July 392.8 401.8 405.2 390.9 378.7 374.6 363.0 366.0 374.8
August 406.5 420.5 415.0 400.1 389.4 388.4 374.3 376.5 385.9
September 408.7 428.9 422.5 409.1 389.4 400.4 386.6 389.1 399.8
October 382.6 408.5 409.5 399.8 389.1 390.3 378.0 383.1 376.6
November 344.0 371.0 383.5 379.8 367.0 367.2 359.0 366.7 351.1
December 312.2 341.5 357.8 361.4 346.1 345.8 341.9 353.0 333.7
Year 335.4 356.9 365.9 362.2 346.9 345.4 339.1 347.0 338.9
ThelargestsizesfortheC1andC2classesoccur,respec- andfromJanuarytoMarch(5%oftheregion),respectively.
tively, when the pruning dates are from April to June (62% ThehighestconcentrationisforC2classwhenthepruning
oftheregion)andfromSeptembertoNovember(78%ofthe dates are in October, representing more than 80% of the
region).TheclassesC3andC4occurmostlywhentheprun- Brazilian Northeast, while pruning periods in May present
ingisdonefromDecembertoFebruary(28%oftheregion) morethan65%ofareasclassifiedasC1.
6 ISRNAgronomy
550
490
JJaannuuaarryy FFeebbrruuaarryy MMaarrcchh AApprriill
430
m)
m
(
GS
R
W
V
370
MMaayy JJuunnee JJuullyy AAuugguusstt
310
SSeepptteemmbbeerr OOccttoobbeerr NNoovveemmbbeerr DDeecceemmbbeerr
250
Figure3:Mapsofthewinegrapewaterrequirements,cv.Syrah,fordifferentpruningdates,anaveragegrowingseasonoffourmonths
(VWRGS),andthebaselineconditions(1961–1990),intheBrazilianNortheasternregion.
Table2:Meanvaluesofthevineyardwaterindexforthewinegrape,cv.Syrah,consideringanaveragegrowingseason(VWI )offour
GS
monthsandthebaselineconditions(1961–1990),intheBrazilianNortheasternstatesofMaranha˜o(MA),Piau´ı(PI),Ceara´(CE),RioGrande
doNorte(RN),Para´ıba(PB),Pernambuco(PE),Alagoas(AL),Sergipe(SE),andBahia(BA).
Pruningdate VWI VWI VWI VWI VWI VWI VWI VWI VWI
GSMA GSPI GSCE GSRN GSPB GSPE GSAL GSSE GSBA
January 3.52 2.18 1.92 1.39 1.46 1.28 0.99 0.94 1.32
February 3.36 1.89 2.07 1.59 1.61 1.35 1.30 1.35 1.11
March 2.67 1.41 1.79 1.51 1.55 1.30 1.55 1.67 0.90
April 2.48 1.36 1.70 1.47 1.50 1.27 1.52 1.65 0.88
May 0.77 0.24 0.49 0.64 0.75 0.69 1.37 1.62 0.41
June 0.39 0.11 0.19 0.37 0.49 0.49 1.03 1.23 0.34
July 0.34 0.17 0.09 0.20 0.30 0.33 0.68 0.85 0.38
August 0.45 0.36 0.07 0.10 0.18 0.23 0.42 0.58 0.59
September 0.71 0.61 0.12 0.10 0.18 0.27 0.33 0.44 0.84
October 1.24 1.00 0.32 0.20 0.29 0.40 0.34 0.41 1.11
November 1.93 1.44 0.69 0.45 0.55 0.63 0.46 0.49 1.32
December 2.76 1.89 1.30 0.90 1.00 0.98 0.69 0.63 1.36
Year 1.72 1.06 0.90 0.74 0.84 0.77 0.89 0.99 0.88
ISRNAgronomy 7
6.00
4.80
JJaannuuaarryy FFeebbrruuaarryy MMaarrcchh AApprriill
3.60
GS
WI
V
2.40
MMaayy JJuunnee JJuullyy AAuugguusstt
1.20
SSeepptteemmbbeerr OOccttoobbeerr NNoovveemmbbeerr DDeecceemmbbeerr
0.00
Figure4:Mapsofthevineyardwaterindicatorforthewinegrape,cv.Syrah,fordifferentpruningdates,anaveragegrowingseasonoffour
months(VWIGS),andthebaselineconditions(1961–1990),intheBrazilianNortheasternregion.
3.2. Projected Vineyard Thermohydrological Conditions. average annual values are expected to have a reduction of
Table3 presents the averaged values of the differences (Δ) more than −0.60 by the projected year of 2080 from both
for the wine grape thermohydrological indicators, between IPCC scenarios. The exceptions are for pruning dates from
the baseline conditions (1961–1990) and the projected years NovembertoDecemberfortheprojectedyearof2020andthe
(2020, 2050, and 2080), considering the IPCC A2 and B2 IPCCA2emissionscenario,whenthevaluesremainstable,as
emission scenarios for the entire Brazilian Northeastern aconsequenceoftheexpectedincreasesin𝑃 .
GS
region. Thespatialvariationsofthe𝑃 differencesbetweenthe
dateA; hgoewneervaelri,zetdhe𝑇lGoSwiensctrΔea𝑇sGeSisvaelvuiedsenatrefoprreadniyctpedrunwiinthg btharseeelidnieffearnedntthweinpergorjeacpteepdryuenairnsg(GdΔSa𝑃teGsSa)loinngptehreceynetaarg,teask,ifnogr
pruningoccurringfromJunetoAugust.Ontheotherhand, as reference the cv. Syrah, in the Brazilian Northeastern
the highest ones are from November to March, being even region,areshowninFigure6.Positivevaluesmeanincreases,
∘ −1
largerthan5.0 CGS ,consideringtheprojectedyearof2080 whilethenegativeonesrepresentdecreases.
andtheIPCCA2emissionscenario.These𝑇GSincreaseswill ForbothIPCCemissionscenariosstrong𝑃GSreductions
makethevineyardwaterconsumptionrise,asevidencedby arepredictedinlargeareas,mainlywhenthepruningdates
the predicted ΔVWRGS averages, higher than 180mmGS−1 arearoundMay.However,insomeplaces,morenotablefor
forpruningdatesinDecember. pruningcentredinJanuaryinthesouthernsideofBahia(BA)
In parallelto the 𝑇GS increases, decreases in 𝑃GS values, state, there are signs of rainfall increases, especially for the
accordingtothepruningdates,arealsogenerallyevident.The projectedyearsof2020and2050.
most negative ΔVWRGS valuesareduringtherainyperiod, ThespatialvariationsoftheVWRGSdifferencesbetween
whenthe𝑃GSvaluesareexp−e1ctedtohaveanaveragereduction the baseline and the projected years (ΔVWRGS), for three
of more than 250mmGS by the year 2080, for pruning differentwinegrapepruningdateconditionsalongtheyear,
datesbetweenFebruaryandMarch. taking the cv. Syrah as reference, in the Brazilian North-
ThesimultaneousincreasesinVWRGSandreductionsin eastern region, are presented in Figure7, also in percent-
𝑃GS will cause a progressive negative trend in VWIGS. The ages.
8 ISRNAgronomy
JJaannuuaarryy FFeebbrruuaarryy MMaarrcchh AApprriill
MMaayy JJuunnee JJuullyy AAuugguusstt
SSeepptteemmbbeerr OOccttoobbeerr NNoovveemmbbeerr DDeecceemmbbeerr
C1:VWI ≤2andT <24∘C C3:2<VWI ≤4
GS GS GS
C2:VWI ≤2andT ≥24∘C C4:VWI >4
GS GS GS
Figure5:Classmapsofthethermohydrologicalconditionsforthewinegrape,cv.Syrah,underdifferentpruningdates,anaveragegrowing
seasonoffourmonths,andthebaselineconditions(1961–1990),intheBrazilianNortheasternregion.
Although all areas have predictions for rising vineyard thepredictionsofreducing𝑃GS andincreasingVWRGS.The
water demands, lower ΔVWR values are verified for the mostnegativeΔVWI valuesareintheNorthwesternside
GS GS
2020 projected year, with the minor ranges for pruning ofMaranha˜o(MA)state.FortheSouthwesternsideofBahia
around September, mainly in the southern side of Bahia (BA)state,moreincreasesinVWIGSarepredicted.
(BA) state. Considering the projected year of 2080 strong Analyses were done on how the initial four thermohy-
increasesarepredicted,especiallyduringthewettestperiod drologicalclassesforwinegrapecouldbechangedalongthe
representedbythepruningcentredinJanuaryforIPCCA2 IPCC projected years, considering three different pruning
emissionscenario,withhighlightsforCeara´(CE)andPiau´ı dateconditionsalongtheyear,forthereferencecv.Syrah,in
(PI) and the western part of Rio Grande do Norte (RN), theBrazilianNortheasternregion(Figure9).
Para´ıba(PB),andPernambuco(PE)states. By the projected year of 2080, almost all the Brazilian
The spatial variation for the differences between the NortheasternstatesarepredictedtopresentlargerC2areas.
baselineandtheprojectedyearsofthevineyardwaterindi- However, for pruning dates around May, there are still
cator(ΔVWI ),forthreedifferentwinegrapepruningdate predictions of the C1 class, mainly in the southern side of
GS
conditionsalongtheyear,takingasreferencethecv.Syrah,in Bahiastate.
theBrazilianNortheasternregion,isshowninFigure8. C3areaswillprogressivelybereduced,beingrestrictedfor
Ingeneral,therearedecreasesinVWIGS,withthehighest pruningdonearoundJanuary,whiletheworstclassC4arising
onesoccurringforpruningdatesaroundJanuaryasaresultof intheNorthwesternpartofMaranha˜ostate,forpruningdates
ISRNAgronomy 9
Table 3: Average differences for the wine grape growing season values of air temperature (ΔT ), precipitation (ΔP ), vineyard water
GS GS
requirements(ΔVWR ),andvineyardwaterindex(ΔVWI )betweenthebaselineconditions(1961–1990)andtheprojectedyearsof2020,
GS GS
2050,and2080,intheBrazilianNortheasternregion,consideringthereferencecv.Syrah:IPCCA2(a)andB2(b)emissionscenarios.
(a) A2emissionscenario
Δ𝑇 (∘C) Δ𝑃 (mm) ΔVWR (mm) ΔVWI (—)
Pruningdate GS GS GS GS
2020 2050 2080 2020 2050 2080 2020 2050 2080 2020 2050 2080
January 1.5 3.0 5.6 −7.4 −88.0 −217.1 31.8 68.9 170.9 −0.20 −0.57 −1.14
February 1.6 3.1 5.5 −110.4 −165.9 −269.3 32.3 69.3 156.7 −0.51 −0.79 −1.22
March 1.6 3.1 5.3 −161.8 −206.5 −265.8 27.6 60.6 132.9 −0.64 −0.84 −1.10
April 1.5 3.0 5.0 −177.1 −198.9 −233.9 25.9 53.1 108.9 −1.08 −1.17 −1.30
May 1.4 2.8 4.6 −121.9 −137.1 −148.6 22.7 44.6 86.1 −0.39 −0.44 −0.48
June 1.3 2.6 4.1 −89.5 −97.3 −102.7 22.8 42.0 71.7 −0.26 −0.29 −0.30
July 1.3 2.6 4.0 −84.7 −89.6 −94.8 19.8 40.4 72.4 −0.23 −0.25 −0.26
August 1.3 2.7 4.2 −84.9 −91.7 −114.0 19.7 43.1 89.5 −0.22 −0.23 −0.31
September 1.5 2.9 4.5 −57.2 −76.5 −124.3 19.3 46.3 112.5 −0.16 −0.18 −0.36
October 1.5 2.9 5.0 13.4 −38.5 −118.0 19.1 48.5 119.3 −0.01 −0.18 −0.44
November 1.5 3.0 5.4 59.9 −5.6 −129.3 28.6 62.4 155.8 0.07 −0.28 −0.62
December 1.5 3.0 5.6 75.4 −11.1 −142.1 29.3 65.9 186.1 0.09 −0.28 −0.85
Average 1.5 2.9 4.9 −62.2 −100.6 −163.3 24.9 53.8 121.9 −0.30 −0.46 −0.70
(b) B2emissionscenario
Δ𝑇 (∘C) Δ𝑃 (mm) ΔVWR (mm) ΔVWI (—)
Pruningdate GS GS GS GS
2020 2050 2080 2020 2050 2080 2020 2050 2080 2020 2050 2080
January 1.3 2.6 4.0 −106.1 −69.8 −203.9 27.8 58.2 107.9 −0.47 −0.48 −0.99
February 1.4 2.8 3.6 −133.8 −162.8 −252.1 29.2 60.8 86.6 −0.57 −0.75 −1.07
March 1.3 2.6 3.4 −172.0 −207.2 −267.0 23.7 50.5 68.0 −0.65 −0.82 −1.03
April 1.2 2.5 3.4 −179.4 −198.9 −222.8 21.8 43.0 65.3 −1.08 −1.16 −1.25
May 1.2 2.3 3.2 −124.7 −135.7 −143.9 19.5 36.7 54.2 −0.39 −0.43 −0.46
June 1.1 2.2 2.9 −91.1 −97.8 −99.4 20.0 35.2 49.8 −0.27 −0.29 −0.29
July 1.3 2.1 2.8 −85.1 −93.4 −93.3 16.5 31.9 46.9 −0.23 −0.25 −0.25
August 1.1 2.2 3.0 −82.6 −90.3 −105.0 16.4 34.5 53.8 −0.22 −0.24 −0.28
September 1.3 2.5 3.0 −56.3 −72.2 −110.6 16.3 37.8 50.4 −0.16 −0.21 −0.31
October 1.2 2.5 3.6 −62.2 −17.1 −107.0 14.9 54.2 78.2 −0.19 −0.11 −0.37
November 1.3 2.7 4.0 −30.0 22.9 −98.1 25.7 37.4 100.9 −0.16 −0.10 −0.47
December 1.4 2.8 3.7 −25.1 11.5 −130.7 26.4 57.7 93.5 −0.18 −0.20 −0.64
Average 1.3 2.5 3.4 −95.7 −92.6 −152.8 21.5 44.8 71.3 −0.38 −0.42 −0.62
∘
duringtherainyconditionsinJanuary,willpracticallydisap- temperaturefrom25to30 C[6].Ontheotherhand,theair
∘
pearalongtheyears(seeFigures7and9). temperature values are not below the threshold of 10 C [5],
whichcouldintroduceadormancystage.
4.Discussion When the pruning is around October, many areas with
∘
thermal conditions outside the upper limit (over 30.0 C)
Accordingtothelong-termdata,therearenothermallimi- oftenoccurandcouldbringsomelimitationsforwinequality.
tationsforwinegrapecropintheBrazilianNortheast,with Theselattersituationswillcontributetohighsugarcontentin
pruning dates in the middle of the year. On one hand, grapesbutwineswithincreasinglevelsofalcohol,lowacidity,
severalsituationsareinsidetheoptimumaveragerangeofair and large pH values. These effects together will promote
10 ISRNAgronomy
IPCC emission scenarios
100
A2 B2 A2 B2 A2 B2
00 00 00 60
22 22 22
00 00 00
22 22 22
20
d years 50 5050 5050 %()
cte 20 2020 2020 PGS
Proje −20 Δ
80 8080 8080 −60
0 00 00
2 22 22
Pruning in January Pruning in May Pruning in September −100
Figure6:Spatialvariationofthegrowingseasonprecipitationdifferencesinpercentage(Δ𝑃 ),betweenthebaseline(1961–1990)andthe
GS
projectedyearsof2020,2050,and2080,consideringthreedifferentpruningdatesalongtheyear,anaveragegrowingseasonoffourmonths
forthecv.Syrah,andtheIPCCA2andB2emissionscenariosintheBrazilianNortheasternregion.
a wine unbalance with instability for the phenolic and rainfalls reduce the ripening capacity of grapes, and the
aromaticcomposition[8–10].Inaddition,secondaryeffects impossibility of water stress application is unfavourable for
related to declines in soil structure and increases of soil the organoleptic wine quality [7]. However, the effects of
salinity could occur [15, 16], favouring high concentrations moisture excess are minimized along the IPCC projected
ofNa,K,andClinthetropicalwines[17]. years.
Normally,thehighestvineyardwaterrequirementsoccur Consideringthelong-termweatherdataof1961–1990,the
when the pruning dates are centred in September and the pruningperiodswiththebestthermohydrologicalconditions
lowest when they are around March. Among the Brazilian forwinegrapecrop(class C1)arefromMaytoJune.High-
Northeasternstates,Piau´ı(PI),Ceara´(CE),andRioGrande lights are for Bahia (BA), Pernambuco (PE), Para´ıba (PB),
do Norte (RN) are highlighted, showing the largest evapo- Alagoas (AL), Sergipe (SE), and the west side of Maranha˜o
transpiration rates, which may correspond to good yield if (MA)withthelargestareasinsidethisclass.Theworstther-
waterisavailable.However,somecaremustbetakenincase mohydrologicalclass (C4) onlyoccurs intheNorthwestern
of water scarcity, having ample room for wine grape water partofMaranha˜o(MA)state,whenthepruningisbetween
productivityimprovementsinsituationsofloweratmospher- January and March. In this last class, the highest levels
icdemands[24]. of natural humidity compromise the grape sanity and the
Comparing the long-term regional daily averaged vine- enological potential [19]. It is important to note that, even
−1
yardwaterrequirementsof2.5to3.3mmday fromthecur- if C3 and C4 areas not being suitable during the wettest
rent study with water use from five experiments under periodoftheyearintheBrazilianNortheast,theywillpresent
different conditions [38–42], the results from the upscaling favourableconditions(C1class)whenthepruningdatesare
techniques used in the current study seem to be plausible. fromJunetoOctober.
However, as the growing seasons in tropical climates are Takingintoaccounttheprojectedyears,therearegeneral
shorter, the total evapotranspiration rates are lower than air temperature increases during the growing seasons with
thosefromtemperateconditions. incrementsofC2anddecreasesinC1areas,whichmaycon-
Aftercomputingtheongoingandoutgoingcomponents tributetomoreproblemsforelaboratingtheBraziliantrop-
oftheclimaticwaterbalance,itwasobservedthatthelowest ical wines, because of increments of alcohol content and
naturalvineyardmoistureconditionsoccurforpruningdates decreasesofacidity,increasingpH[9,10].
from May to August. These conditions will avoid plant dis- Themostimportanteffectfromclimatechangesforwine
eases, root respiration problems, and direct damage to the production in the Brazilian Northeast region should be to
berriespromotedbyexcessofprecipitation,favouringbetter takemorecareoftheincreasingthermalconditionsregarding
qualityofbothmustandwine[19].Thehighestbaselinemois- thewinequality.Examplesofattentiontothisproblemarethe
ture levels for pruning done from January to April should additionoftartaricacidtoaddresstheimbalanceofacidity
promote the worst wine commercial production. Excessive andthereverseosmosisprocedurestodealcoholisewine[21].