Analysis and Diagnosis of the Agrarian System in the Niayes Region, Northwest Senegal

25 Pages·2017·3.34 MB·English

agriculture
Article
Analysis and Diagnosis of the Agrarian System in the
Niayes Region, Northwest Senegal (West Africa)
YohannFare1,*,MarcDufumier1,MyriamLoloum1,FannyMiss2,AlassanePouye3,
AhmatKhastalani3andAdamaFall4
1 Unitéd’EnseignementetdeRechercheAgricultureComparéeetDéveloppementAgricole,
AgroParisTech.16,rueClaudeBernard,F-75231ParisCEDEX05,France;
[email protected](M.D.);[email protected](M.L.)
2 ÉcoleNationaleduGénieRural,desEauxetdesForêts,AgroParisTech,19AvenueduMaine,75732Paris
CEDEX15,France;[email protected]
3 EcoleNationaleSupérieured´Agriculture(ENSA)deThiès,B.PA296-Thiès,Sénégal;
[email protected](A.P.);[email protected](A.K.)
4 SOSSAHELInternational,21001Thiès,Senegal;[email protected]
* Correspondence:[email protected];Tel.:[phone]
AcademicEditor:LesCopeland
Received:17April2017;Accepted:17July2017;Published:20July2017
Abstract: TheagrariansystemAnalysisandDiagnosisisusedforthisstudy,thegoalofwhichwas
toprovideacorpusofbasicknowledgeandelementsofreflectionnecessaryfortheunderstanding
theNiayesfarmingsystemsdynamicsinSenegal,WestAfrica. Suchholisticworkhasneverbeen
donebeforeforthissmallregionthatprovidesthemajorityofvegetablesinthearea,thankstoits
microclimateandaccesstofreshwaterinanaridcountry. Readingofthelandscapeandhistorical
interviewscoupledwithfine-tunedhouseholdsurveyswereusedtobuildatypologyofagricultural
productionunits(eachtypebeingrepresentedbyaproductionsystem). Themainphaseswithinthe
region’shistoryweredistinguished. Beforecolonization,agriculturewasbasedongatheringand
shiftingagriculture(milletandpeanut)inthesouthernregionandtranshumantstockbreedingin
theNorth. Duringcolonization,marketgardeningbecameasourceofincomeasaresponsetocities’
increasingdemand. Twomajordroughts(inthe1970sand1980s)haveacceleratedthismovement.
ExtensionofmarketgardeningareasandintensificationofactivitiesweremadepossiblebySahelian
migrants’ influx and the creation of mbeye seddo, a contract that allows for sharing added value
betweentheemployerandseasonalworkers,namedsourghas. Overthepast20years,the“racefor
motorization”hascreatedimportantsocialgaps(addedvaluesharingdeservesreview)andariskof
overexploitationofgroundwater.
Keywords: comparativeagriculture;surveyonfarming;socioeconomicdifferentiation;Senegal
1. Introduction
From 3.3 million inhabitants in 1961, Senegal will count its population at about 17 million in
2020. Feeding an unceasingly growing population and supplying towns with fresh and quality
vegetablesaswellasfruitsarechallengesforthecountry,whichhasmainlySahelianconditions. Due
to urban growth, competition for foreign products and devaluation of West African FCFA (Franc
delaCommunautéfinancièreenAfrique,thecurrencyofeightindependentstatesinWestAfrica),
Senegalsawanincreaseinimportsofonions,potatoes,rutabagasandcarrots. Productionfromthe
Niayesagriculturalregionseemstoplayanon-negligibleroleinimportationtosatisfynationalneeds.
Infact,Niayesfarmersprovideanywherefromhalftotwo-thirdsofthenationalproductionoffresh
vegetables (tomatoes, onions, rutabagas, cabbages, carrots, etc.) [1]. Despite the dynamism of the
Agriculture2017,7,59;doi:10.3390/agriculture7070059 www.mdpi.com/journal/agriculture
Agriculture2017,7,59 2of25
Niayesproductionsystems,therehasneverbeenanyholisticworktoprepareSenegalesepolicymakers
tofacethechallengesoffeedingthecitiesthataregrowingwithNiayesproduction. Ourresearchwas
conductedwithinagriculturaldevelopmentprojects,ledbyanon-governmentalorganization(NGO)
namedSOSSAHEL,andaimsat:
• Understanding conditions of market gardening development in the Niayes (environmental
parameters: Soil fertility, water resources, etc.) and the diversity of production units in this
regiontofine-tuneforthcomingprojects.
• Determining the conditions necessary for the Niayes to better contribute to the country’s
agricultural production. Beyond technological choices, we had to understand the economic
rationalityofNiayes’productionunits. Understandingtheirrationalitywillhelpthisprojectto
bettersuggestsocial,economicandpoliticalactionsthatwouldbeabletoboostproductionand
createjobswhilerespectingtheenvironment.
To address these objectives, this study has adopted as a theoretical reference the concept of
the“AgrarianSystem”developedattheFrenchAgriculturalResearchNationalInstitute,Agrarians
SystemsandDevelopmentDepartment(INRA-SAD)[2–4]. Thisholisticmethodologyhasbeenusedto
describemanysituationsinworldagriculturebutnotintheNiayes[5]. Theextensionofthisapproach
toNiayeswouldenrichourknowledgeoftheworld’sagriculture,inadditiontoprovidinganswersto
theabovementionedquestions.
Originatingfromcomparativeagriculturestudiesandsystemsresearchappliedtoagriculture,
theconceptisdefinedas“amodeofexploitationofagivenagro-system,historicallyconstitutedand
long-lasting,adaptedtothebioclimaticconditionsofagivenspace,andmeetingtherequirementsand
socialneedsofthetime”[2]. “AgrarianSystemanalysisanddiagnosis”isthesurveymethodrelated
totheconceptofanagrariansystem[3,4]. Itisanall-encompassingmethodology,combiningdifferent
levelsofanalysisandthereforecapableofmakingsenseofagriculturalactivitiesoperatedbyfarmers
within a given agricultural district, in a way that accounts for both ecological and socioeconomic
dimensions. Thisholisticapproachaimsatdescribingfarmers’socialandeconomicpracticesand
techniquesandatunderstandingthephenomenathatinfluencethem[4,6]. Italsoallowsforevaluating
thesustainabilityofaregion’sagricultureandcollectingallelementsforfuturetransformationsand
forecasting,withorwithoutanyproject-likeintervention.
Forthisresearchproject,datahavebeencollectedthroughobservationaswellasquestionnaires
andaliteraturereview. Thedatacollectionhasbeenorganizedatdifferentscalesfromthegenerallevel
(nationalsituation)totheparticular(region,thenfarms,plotsand/orherds)followinganiterative
analysis–synthesisprocess. Thisprocessobeysthemethodologyofcomparativeagriculture,which
“favourstheusageofatelescopicchangeofscale,particularlybetweenthethreelevelsofanalysis
privileged by us, i.e., that of the plot or herd for examining practices, that of the production unit
orfarmforintegratingdifferentcroppingandlivestocksystems,andthatofthe(moreorlessvast)
regionorcountryforthepertinentapplicationoftheagrariansystemconcept”[3,4]. Understanding
thedifferentiationofpreviousagrariansystemsisanessentialsteptounderstandingthedynamics
of the production system currently under survey. Within this current agricultural system, farms
haveeitheralwaysusedthesametechniquesorimplementedsimilar“strategies”duetodifferent
access to production means (land, work, capital) and the heterogeneity of regional conditions [3].
Thetechnical–economicevaluationofthefarmssurveyedallowsforabetterunderstandingofthe
differencesbetweenthem[7]. Finally,ananalysisofcurrentprojectsandagriculturalpolicieshelps
withdevelopingfutureperspectivesandpossiblygeneratessomecorrectivemeasurestoimplement
fromthegeneralinterestpointofview.
2. MaterialsandMethods
The survey area is the Niayes, a small agricultural region of Senegal specialising in market
gardening. The boundaries of our study area are set based on geomorphology, climate and main
Agriculture2017,7,59 3of25
agriculturaltrendsasanimportantmarketgardeningarea. Themainboundariesofourstudyarea
weresetasfollows: intheWest,theAtlanticOcean;intheEast,themainrain-fedagriculturalareas
(milAlegrti–cuplteuaren 2u01ts7, s7y, 5s9t em);intheNorth,theSenegalRiver;andintheSouth,theCapeVerdePe3 nofi n24s ula
(Figure1). Thisgeneraldelimitationwasenhancedonsitebyobservationsthatallowedtheprojectto
(Figure 1). This general delimitation was enhanced on site by observations that allowed the project 
determinezones,asrelativelyhomogenoussub-unitsofoursurveyarea.
to determine zones, as relatively homogenous sub‐units of our survey area. 

Figure 1. Location of the Niayes within the main agricultural regions of Senegal. 
Figure1.LocationoftheNiayeswithinthemainagriculturalregionsofSenegal.
On‐site data collection was conducted from 2010 to 2013 with the support of SOS Sahel 
InOtenr-nsaittieondaal ttaeacmosl,l eac ntoionn‐gowvaesrncmoenndtaulc otergdanfirzoamtion2 0(N10GOto). 2T0h1e3se wsuirtvheyths ewesruep cpoomrptleotfedS bOyS fivSea hel
Inteorfn athtieo naaulthteoarsm, ss,oamnetoimn-egso vacecronmmpeanntiaeldo rbgya nloizcaalt ioinnte(rNprGetOer)s.. TIhnetesremseudrivaetey srewsuelrtes choamvep lbeeteend by
fiveporefstehneteadu itnh ofrosu,rs oMmasetteirm’se tshaecsecso,m suppaenriveidsebdy blyo ctahle imntaeirnp raeuttehrosr. [I1n,8te–r1m0]e. dCiiatitzeerness’ ualntsd hfaarvmeebre en
organizations’ acceptance was facilitated by one of the authors’ work with the market gardening 
presented in four Master’s theses, supervised by the main author [1,8–10]. Citizens’ and farmer
union association of Niayes.  
organizations’acceptancewasfacilitatedbyoneoftheauthors’workwiththemarketgardeningunion
First, the study aimed at interviewing groups of elderly farmers who were witnesses to the 
associationofNiayes.
recent evolution of Niayes agriculture. The topic chosen for discussion during the interviews was 
First, the study aimed at interviewing groups of elderly farmers who were witnesses to the
Niayes’  agricultural  history.  Souvenirs  that  we  collected  directly  dated  from  the  1940s.  The 
recentevolutionofNiayesagriculture. Thetopicchosenfordiscussionduringtheinterviewswas
participant groups were sometimes associated with people in charge of the farmers’ organizations, 
Niayes’agriculturalhistory. Souvenirsthatwecollecteddirectlydatedfromthe1940s. Theparticipant
retired people from technical services who stayed and lived in their former working place. Such 
groupsweresometimesassociatedwithpeopleinchargeofthefarmers’organizations,retiredpeople
information was required in order to understand the rationale for their installation. With the purpose 
fromof tdeicvhidniincga lthsee rlvonicge hsiwstohroicsatla pyeerdiodan indtoli sveeqdueinnctehse ainrdfo lormcaetirnwg tohrek sionugvpenlaircse i.nS tuimche, iwnfeo ursmeda tsioomnew  as
requoiurtesdtainndoinrgd eervetontus nads ererfsetraenndcetsh: ethrea tSioecnoanlde fWororthlde iWrianr;s ttahlel aLteioonp.olWd iStehdtahre Spenugrhpoors,e Aobfddoiuv iDdiionugf the
longanhdis Atobrdicoaullapyeer iWodadine tporesseiqduenetniacle stearmnds; ltohcea 1t9in9g5 CthFeAs foruanvce ndiervsailnuattiimone;, awned uthsee d20s0o8m preicoeu stusrtagnesd. ing
evenTthsiratsy rheifsetroerniccaels :inttheervSieecwosn cdoWupolreldd wWiathr ;1t0h0e rLeelaotpeodl dtoS feadrmarsS’ elinfeg hcyocr,leAs bwdeorue DcoioorudfinaantdedA bbyd othuel aye
Wadmeapinre asuidtheonrt,i awlhteor malsso; tthoeok1 9p9a5rtC inFA mfarnayn cofd tehveamlu. aAtiboonu;ta 8n0d fitnhee‐t2u0n0e8dp sruicrveesyusr gweesr.eT uhsierdty toh ihsetolpr ical
inteersvtiaebwlisshc oeucopnleodmwici rtehs1u0lt0s raetl tahtee dhotousfeahrmolsd’ lleifveecl.y Tchlees owbjeerceticvoeo wrdaisn taot oedbtbaiynt thhee mnuaminbaeur tohfo wr,owrkheorsa lso
in each household and those external to the households, the number of people to feed, the technical 
tookpartinmanyofthem. About80fine-tunedsurveyswereusedtohelpestablisheconomicresults
details for each cultural and production system, locating them in time in landscapes, yearly and inter‐
atthehouseholdlevel. Theobjectivewastoobtainthenumberofworkersineachhouseholdandthose
yearly  rotations,  crop  shifts,  income,  inputs  and  manpower,  produce  destinations  (for  self‐
externaltothehouseholds,thenumberofpeopletofeed,thetechnicaldetailsforeachculturaland
consumption, sales, transformation), and access to credit. The choice of farms type for the surveys 
productionsystem,locatingthemintimeinlandscapes,yearlyandinter-yearlyrotations,cropshifts,
was guided by the farmers’ organizations, based on rather general typology standards, but the list of 
income,inputsandmanpower,producedestinations(forself-consumption,sales,transformation),and
farms was validated based on their gardening techniques and practices related to their means of 
accesstocredit. Thechoiceoffarmstypeforthesurveyswasguidedbythefarmers’organizations,
irrigation and their location in the landscape, and therefore gardening soil types. Each investigation 
basedonrathergeneraltypologystandards,butthelistoffarmswasvalidatedbasedontheirgardening
was led by an investigator accompanied by an interpreter, as open or half‐open survey type using a 
survey guide. During the study, we found that sometimes it was necessary to come back several times 
to have more accurate information and be more precise about different periods of the year.
Agriculture2017,7,59 4of25
techniquesandpracticesrelatedtotheirmeansofirrigationandtheirlocationinthelandscape,and
therefore gardening soil types. Each investigation was led by an investigator accompanied by an
interpreter, as open or half-open survey type using a survey guide. During the study, we found
that sometimes it was necessary to come back several times to have more accurate information
andbemorepreciseaboutdifferentperiodsoftheyear. Investigationsatthemarketandwithinthe
SenegaleseNationalAgencyonstatisticsanddemographyprovidedpriceevolutionrelatedtodifferent
productionsinthesurveyarea. Finally,wemetsomemanagersofNGOprojects,nationalprojects,
andmicrofinanceinstitutions,aswellasofficersoftechnicalservicesinthearea. Thosepeopleknow
moreaboutthepastandcurrentprojectsoperatingontheagrariansystem. Theyalsoofferedsome
assistanceduringsurveys;theyhelpedduringtheselectionofrelevantvillages,sharedcontactsof
ruralleadersandsometimesintroducedustovillagers.
2.1. TheSurveyArea
2.1.1. Boundaries
The Niayes area, a small and unique region in Western Senegal. covers approximately
2759km2[11,12],lessthantwopercentofthewholecountry’ssurface. Niayescoverstheareasituated
between Dakar in the south and Saint-Louis in the north, along the country’s northern coast and
5–30kminwidth.
TheNiayesbelongstoaparticularecosystemoftheSahelianstrip. Althoughlocatedatlatitude
14◦30(cid:48) and16◦ North,thisareaisneverthelesscharacterizedbyatropicalclimateofSub-Canariantype
andanoriginalSub-Guineanvegetation[13]. Suchanexceptionisproducedbyamarinetradewind,
relativelyfreshandhumid,generatedbytheAzoresanticyclone(NorthernAtlantic),whichprotects
the northern coast of Senegal from warm and dry harmattan winds [14]. The Niayes agricultural
region’sreliefisasuccessionofsanddunesandinter-dunebasins. Thesequaternary-ageddunesare
establishedinamarlyandlimysubstratumdatingfromtheEoceneandPaleocene[15,16]. Rainfallis
relativelylow,between350and450mmrainperyear,butwateravailabilityisimportantininter-dune
basins.Thisprofusionistiedtothe“NappedesSablesQuaternaires”—NSQ—groundwater,circulating
insandyandsandy-clayeydeposits,relativelypermeable,onamarlyandmarly–limysubstratumof
theEocene,whichisimpermeable[17,18]. Incurrentlandscapes,fromthecontinenttocoastalarea,
fourtypesofdunessucceedeachother:
• Longredandlevelleddunes,orientedfromnortheasttosouthwest,runningparallelwiththe
shoreline,witnessingtheregressiveanddryphase(Ogolien)ofthelasticeage(18,000yearsago).
ThesedunesaresteadyandindicatethebordersoftheNiayesandtheDieri(thelocalnamefor
theancientpeanutbasin).
• Shorterandhigherreddunes,shelteringmuchmorethananywhereelsehumus-bearingsoils
and peat bogs. These dunes would be resulting from Ogolian dunes alteration by a marine
tradewind[16]. Theyareingeneralpermanentbutreviveinsomeplaces.
• Semi-permanentyellowdunes,formingacoastaldunestretchwithvariablewidthfromoneto
fourkilometres. Of20to30mhigh,theyendwithanabruptfrontinthewindypart. Theywould
havebeensettledintheregressivephaseafter5500BCE.Thedepressionsbetweendunesbear
lesshumus[16].
• Whitecoastaldunes,sharp,formingalargebandrangingfromsomedozensofmetersto300m
fromthebeach. Thesandwasbroughtbyrecentcoastalaccumulation(by1800yearsago). They
arepartlymaintainedoffilaotrees(Casuarinaequisetifolia)[14,19,20].
TheNiayesareaishighlypopulatedandcharacterizedbyadynamicagriculturedominatedby
marketgardeningactivities(morethanhalfofthenationalproduction). TheNiayesmakeanimportant
contributiontothefreshvegetablesupplyinDakar. MorethantwomillionpeoplelivedinDakarin
Agriculture2017,7,59 5of25
2006,morethan20%ofSenegal’swholepopulation,andmorethantwo-thirdsofSenegal’spopulation
livelessthan60kmfromcoastalareas[21].
2.1.2. ZoningElements
Agriculture 2017, 7, 59  5 of 24 
Tiedinwithgeomorphology,proximitywithNSQgroundwaterandsoiltypes,andduneand
basi2n.1s.u2.c Zceosnsiinogn Eclaenmbenetds ividedintodifferentzones(Figures2–4andTable1):
Tied in with geomorphology, proximity with NSQ groundwater and soil types, and dune and 
• Acoastaldunestring(A),composedofrawmineralsoils.Onthesedunes,whichcanbepotentially
basin succession can be divided into different zones (Figures 2–4 and Table 1): 
mobilizedbywind,colonialforestryadministrationbytheSenegalesegovernmentestablishedin
 succAe scsoivasetastl adguensea sfitlrainogt r(eAes), sctorimpp(Cosaesdu aorfin raaewq umiseintiefroalila sLo.i)l,sa. Oveng ethtaelseb adrurineersp, rwohteicchti ncgana gbaei nst
thepsaontedn-tsiailltliyn mgroibsikliztoedt hbey bwaisninds, cboeltownieaeln fodruesnterys. administration by the Senegalese government 
established in successive stages a filao trees strip (Casuarina equisetifolia L.), a vegetal barrier 
• Small-sizeddepressions,betweenlevelledandscarcelycollecteddunes(B).Onthisarea,which
protecting against the sand‐silting risk to the basins between dunes. 
stretchesafewhundredsofmetersbehindthefilaotreesstrip,thegroundwaterlevelisnotvery
 Small‐sized depressions, between levelled and scarcely collected dunes (B). On this area, which 
deep (two to five meters). For that reason, undoubtedly, depressions are named “Ndioukis,”
stretches a few hundreds of meters behind the filao trees strip, the groundwater level is not very 
meaning “drawing water with a bucket using a pulley.” Soils are of a siliceous type, poor in
deep (two to five meters). For that reason, undoubtedly, depressions are named “Ndioukis,” 
organicmaterialsandsometimessalinated. NdioukisaremuchmorenumerousintheNorth
meaning “drawing water with a bucket using a pulley.” Soils are of a siliceous type, poor in 
oftheNiayes(Northernzone: fromtheSouthofSaintLouistotheLompouls/mer-Kebemer
organic materials and sometimes salinated. Ndioukis are much more numerous in the North of 
axist;hCe eNnitaryaelsz (oNnoer:tbheertwn ezoenneL: ofrmompo tuhle- KSoeubtehm oef rSaaxinist LanoudisK taoy tahre- TLhoimespaoxuils s(/mcoerrr‐eKsepboenmdeirn gaxtios; the
EasCteernntrbaol uznodnae:r ybeatnwdeeCna pLeomVeproduel‐PKeenbienmseurl aa:xSiso uatnhde rKnazyoanr‐eT:hEieass taoxfist h(ceoCrraepspeoVnedritnegP teon itnhseu la,
KeuEraMsteoruns bsoa,uSnédbairkyo atnand eC,aBpaey Vakehrd,eD Pieenndinesru)l.a: Southern zone: East of the Cape Verte Peninsula, 
• AdKuneuera Mreoaupsasart, lSyéfibixkeodtabnye,s Bcaayrcaekhsh, rDuibenbdyearn).d  woodedvegetation,withsandy-soiledinter-dune
 depAre dssuinoen sa,resali gphatrltyly mfixoeisdt bayn dscoarfcoe cshhrreubcboylo aunrd. Twhoiosdaerde ave(Cge)tactoiovne,r swtihthe sianntedrym‐seodileiadt einptearr‐t of
dune depressions, slightly moist and of ochre colour. This area (C) covers the intermediate part 
Niayes(from300to2000mtowardslands,tothewest). Depressionsareofvariedsizesandforms.
of Niayes (from 300 to 2000 m towards lands, to the west). Depressions are of varied sizes and 
• Theancientriverbedorlakezones(DandE)resultinginlargedepressions;theNSQisatgrounds’
forms. 
level. Depressionsareembanked,clayeyorevenpeaty(localname: xour;weclassifythemunder
 The ancient riverbed or lake zones (D and E) resulting in large depressions; the NSQ is at 
subzoneD)orclayeyandmuddysoils(calledbaninWolof)(subzoneE).TherelicsofGuinean
grounds’ level. Depressions are embanked, clayey or even peaty (local name: xour; we classify 
vegetationcanbeseeninthisarea. Aswecanseeintheliterature,theterm“Niayes”wasfirst
them under subzone D) or clayey and muddy soils (called ban in Wolof) (subzone E). The relics 
associatedwiththiswellknowsandearlypopulatedarea. Wecallthispartthe“peatyNiayes
of Guinean vegetation can be seen in this area. As we can see in the literature, the term “Niayes” 
zonwe.a”s Tfihrset wasisdotchiaotefdt hwaittha rtheais iwsemllu kcnhowmso arnedi meaprloyr tpaonptuilnattehde asroeau.t Whae ncdallc tehnistr peatrht athnei “tpiseainty the
nortNhia(Fyiegs uzroen3e).”. The width of that area is much more important in the south and centre than it is 
• Theinla tshted nuonretsh a(Freigau,wreh 3e)r. eaccesstowaterallowsmarketgardeningwithadapteddrainagemeans.
 SoilTshaer elaosft ddiuonretsy pareeian, whehiegrhet aacncdesos ftod ewckatedri oarllionwtsh embaorktteot mga(rFd)e.nTihnigs wcoitnhs taitduatpetsedth derbaoinuangde ary
withmtehaensD. iSeoriil.s are of dior type in height and of deck dior in the bottom (F). This constitutes the 
boundary with the Dieri. 
• IntheDierieasternboundary(GandH),whichmarksthestartoftheSenegalesepeanutbasin,
 In the Dieri eastern boundary (G and H), which marks the start of the Senegalese peanut basin, 
thefirstsubzone(G)isnotcultivatedbutreservedasalivestockwayandforforestryproduce
the first subzone (G) is not cultivated but reserved as a livestock way and for forestry produce 
collection. The‘H’areainthediagram(Figure2)iscultivatedwithamillet/peanutsystemunder
collection. The ‘H’ area in the diagram (Figure 2) is cultivated with a millet/peanut system under 
coverofAcaciaalbidaDel.
cover of Acacia albida Del. 

FiguFriegu2r.e 2G. Geoeloologgicicaall sseeccttiioonn oof fthteh NeiNayieasy aensda lnocdatlioocna otifo angroof‐eacoglroog-ieccaol lzoogniecsa (ladzoapnteesd (farodmap Pteezderfirlo m
Pezeert ialle. t[2a2l].)[. 22]).
Agriculture2017,7,59 6of25
Agriculture 2017, 7, 59  6 of 24 

Figure 3. Zoning of the survey region. 
Figure3.Zoningofthesurveyregion.

Figure 4. Diversity of depressions and soils, according to topography (and therefore proximity of 
the water table).
Agriculture2017,7,59 7of25

Figure4.Diversityofdepressionsandsoils,accordingtotopography(andthereforeproximityofthewatertable).
Table1.Diversityofdepressionsandsoils,accordingtotopography(andthereforeproximityofthewatertable).
Dieri
HighBasinsof
Zones Ndioukis(B) Semi-FixedDunes(C) PeatyNiayes(DandE) ContinentalDunes(F) PastoralTransitionArea RainyCultivating
andDieriArea(G) Area(H)
Altitude(≈level
10–15m(moreimportantlevel
differencebetween
Fivetotenmeters(m) 10–20m differencetowardsFassBoyewith 15–25m 25to30m 30to45m
thalwegbottomand
about20msummits)
dunetop)
Relativelyeasyaccess
Watergroundisin Waterisalmostflushinginthe Difficultaccess Verydeepwaterground(>25m),forannualplants,
Accesstowater (watergroundisatseven
averagetwotofivemeters. basinbottom. (15–20m) availablewaterisrain).
tofifteenmeters)
Sandy(dior)inheightand Clayeyandpeaty(xour)inbasin Sandydiortype,withveryslighttexturalvariationon
Sandyandverypoorin
Soils sandyandmuddyor bottom,clayeyandsandyin Sandy(Dior) thetopofdunes(weaktexturalstability)inslope
organicmaterial.
deck-diorinbasinbottom. mid-slope(ban) bottom(withfewsiltsaccumulatedbycolluviation).
Guinean-typevegetationwithpalm Variousacaciasand Shrubbysavannawith
Steppe,withscarce Variousacaciasand
trees(ElaeisguineensisandCocos combretacea.Cactacea Detariumsenegalensis,Cassia Woodedparkswith
Spontaneousandwoody Casuarinaequisetifolia,due combretacea.Cactacea
nucifera)Withaquaphyleplants andeuphorbiacea sieberiana,Celtisintegrifolia, Acaciaalbidaand
vegetation toclosepresenceoffilao andeuphorbiacea
(Nymphaealotus,Phragmitesvulgaris, disseminatedby Prosopisafricanaand Adansoniadigitata.
treesstrip. disseminatedbyhumans.
Typhaaustralis) humans. Securidacalongipediculata
1
Agriculture2017,7,59 8of25
2.2. DefinitionoftheAgriculturalSurface
Farmersweregenerallyabletoprovideuswithinformationonthesurfaceofplotstheycultivated
inhectares. Whenthatwasnotthecase,wesometimeshadtomeasurethesurfaceorestimatethetotal
Agriculture 2017, 7, 59  8 of 24 
sownsurface(e.g.,sumofalldisseminatedplotsownedbythesamefarmer). Thelandreserveofeach
farmerhasalsobeenestimated.
2.2. Definition of the Agricultural Surface 
2.3. EconomicAnalyFsiasrmers were generally able to provide us with information on the surface of plots they 
cultivated in hectares. When that was not the case, we sometimes had to measure the surface or 
2.3.1. EvaluatioenstoimfaPtee rtfhoer tmotaanl scoewsno fsuCrrfaocpep (ein.gg., Ssuymst eomf aslla dnisdseLmivineastteodc pkloFtas romwinnegd Sbyys ttheem same farmer). The 
land reserve of each farmer has also been estimated. 
Grossaverageproduct(GP)ofacroppingsystemorlivestock:
2.3. Economic Analysis 
GP=Q×P, (1)
2.3.1. Evaluation of Performances of Cropping Systems and Livestock Farming System 
whereQisthequanGtriotyssh aavrevraegsete pdroadnudct P(GiPs)t hofe ap crriocpep/inugn isty.stem or livestock: 
Foodpricesaresubjecttochangeyear-round.Formarketgardeningproduce,weusedtheaverage
GP = Q × P,  (1)
priceatthepeakperiodofsales.Thiswaseasyenoughtosetupduetotheperishablequalityofmarket
where Q is the quantity harvested and P is the price/unit. 
gardeningproduce.Thepriceoflivestockproduceismorestable,exceptforsheepsoldforyearlyfestivities
Food prices are subject to change year‐round. For market gardening produce, we used the 
(end-of-yearfestivities,“Tabaski”and“Eid,”whichisthenameoftheendoftheRamadanfast).
average price at the peak period of sales. This was easy enough to set up due to the perishable quality 
Netvalueoafd mdaerdke(tN gaVrAde)n:iEngv aplruodauticoen. Tohfe vparilcuee oaf dlivdeesdtocakl lporwodsufcoer isa mssoerses sitnagblteh, eexccerepat tfoior nshoefepw seoaldlt fhor 
fromtheperspeycetaivrley ofefstthiveitcieosm (emndu‐noift‐yy.eaInr foesrtdiveirtiteos,c “oTmabpaasrkei”t hanedp “eErfiod,r”m wahniccehs iso fthteh enadmifef eorfe tnhtec ernodp poifn tghe 
systems,theecoRnamomadiacnr feassut)l.t sweremodelledaccordingtoalinearmodel:
Net value added (NVA): Evaluation of value added allows for assessing the creation of wealth 
from the perspective NofV tAhe/ wcoomrmkeurn=itya.* SIn/ worodrekr etro −comb,pare the performances of the different 
cropping systems, the economic results were modelled according to a linear model: 
a=(GP−IC −Amt )/hectare (2)
p p
b=(INCVA/+wAormketr = )a,*S/worker − b,  
np np
a = (GP − ICp − Amtp)/hectare  (2)
where S is the area farmed (in hectares), GP is the gross average product per farmed hectare, IC
b = (ICnp + Amtnp), 
isthecostofvariableinputs, i.e., valueofgoodsandservicesthathavebeentransformedorfully
where S is the area farmed (in hectares), GP is the gross average product per farmed hectare, IC is the 
consumed during the production process (fertilizers, manure, pesticides, etc.) proportional (p) or
cost of variable inputs, i.e., value of goods and services that have been transformed or fully consumed 
non-proportional(np)tothefarmedarea;Amt: istheaveragecostperhectareoftheamortizationand
during  the  production  process  (fertilizers,  manure,  pesticides,  etc.)  proportional  (p)  or  non‐
maintenanceofequipmentandfixedassets,proportional(p)ornon-proportional(np)tothefarmed
proportional (np) to the farmed area; Amt: is the average cost per hectare of the amortization and 
area;andNVAmisatinhteennaentcpe roof dequucitpiomnenotf awnde afilxtehdp aesrsewts,o prrkoepro,rit.eio.,ntahl e(pn) eotr nporno‐dpurocptiovrittioynoafl (lnapb)o tuo rt.he farmed 
area; and NVA is the net production of wealth per worker, i.e., the net productivity of labour. 
2.3.2. TypologyofProductionSystems
2.3.2. Typology of Production Systems 
To construct the typology, we used structural variables (length of the farm, type of irrigation
To construct the typology, we used structural variables (length of the farm, type of irrigation 
equipment—manual,motorized,intermediate,numberoffamilyworkers)andfunctionalvariables.
equipment—manual, motorized, intermediate, number of family workers) and functional variables. 
Incomparativeagriculturestudies,therearethreemaingroupsoffarmtypes: family,familybusiness,
In comparative agriculture studies, there are three main groups of farm types: family, family business, 
andcapitalist. InTable2,wegivesomecriteriarelatedtothesethreemodelsoffarms.
and capitalist. In Table 2, we give some criteria related to these three models of farms.  
Table2.TypeTsaobflem 2o. Tdyeplseso offa mgoridceulsl touf raaglrpicruoltduuraclt pioronduunctiitosn[ u2n3i,2ts4 []2.3,24]. 
Entrepreneurial  Family 
   EntrepAregnreicuurlitaulrAesg ricultures FamiAlygrAicgurlitcuurletus res

Typesofproductionunits Enterprisefarm Familybusinessfarm Familyfarm
Types  Sopfe cializeinsupervisionof Workonfarmand Familylabour;no
Labour Enterprise farm  Family business farm  Family farm 
production unihtsi redlabour supervisehiredlabour permanenthiredlabour
2.3.3. EvaluationofPerformanceSopfeEciaalcizhe Tiny pseupoefrvPisrioond uctWioonrk Sysotne mfarm  and  Family  labour;  no 
Labour 
of hired labour  supervise hired labour  permanent hired labour 
To refine the interpretation of results of farms’ typology, and really measure the net family’s
revenue(RA),itisrecommendedtowithdrawthepartofincomeredistributedtoworkingpersons
2.3.3. Evaluation of Performance of Each Type of Production System 
outsideofthefamily(salaryorbenefitsharing)[3];wehavebuiltasecondlinearmodelasfollows:
Agriculture 2017, 7, 59  9 of 24 
Agriculture2017,7,59 9of25
To refine the interpretation of results of farms’ typology, and really measure the net family’s 
revenue (RA), it is recommended to withdraw the part of income redistributed to working persons 
outside of the family (salaryR Aor/ bfaemneifliyt wshoarrkinegr)= [3A]*; Sw/efa hmaviley bwuoilrtk ae rse−coBn,d linear model as follows: 
A=(GP−IC −Amt −landpropertytaxes−rents)/hectare (3)
p p
RA/family worker = A*S/family worker − B, 
B=(IC +Amt +taxes+salaries−subsidies)/familyworker.
np np
A = (GP − ICp − Amtp − land property taxes − rents)/hectare  (3) 
Evaluationofthefarm’sincomeallowedthestudytoassesstheprofitabilityoftheactivityfrom
thefarmer’spointofviBew = ((IvCenrp s+u Asmnetntp v+ ataluxeesa +d sdaeladr,iews h− iscuhbsriedpieres)s/efanmtsiltyh weocrrkeeart.i onofwealthfromthe
perspectiveofthecommunity). Whilevalueaddedandproductivitymeasuretheintrinsiceconomic
Evaluation of the farm’s income allowed the study to assess the profitability of the activity from 
efficiencyoftheproductionsystemasavaluecreationprocess,itisthefarmincomethatisinaposition
the farmer’s point of view (versus net value added, which represents the creation of wealth from the 
toexpresstheshareofvalueadded(potentiallyincreasedbythesubsidiesreceived), enablingthe
perspective of the community). While value added and productivity measure the intrinsic economic 
farmertosupporthisfamilyand,ifpossible,toinvestsoastoincreasehiscapitaland,ultimately,the
efficiency of the production system as a value creation process, it is the farm income that is in a 
productivityofhisfarm[1–3].
position to express the share of value added (potentially increased by the subsidies received), 
For each production system-type we have evaluated the average annual income. We then
enabling the farmer to support his family and, if possible, to invest so as to increase his capital and, 
constructedarepresentationofeconomicperformanceperfamilyworkeraccordingtotheavailable
ultimately, the productivity of his farm [1–3]. 
areaperfamilyworker. Finally,wehavecomparedthisannualincome/familyworkerto:
For each production system‐type we have evaluated the average annual income. We then 
constructed a representation of economic performance per family worker according to the available 
• A survival threshold (ST): such a comparison informs us about the future of the farm and its
area per family worker. Finally, we have compared this annual income/family worker to: 
capacitytodevelop(Figure5).
 A survival threshold (ST): such a comparison informs us about the future of the farm and its 
capacitIyf tRoA de>vSeTlo,pth (eFnigtuhreep 5r)o. d uctionunitisincreasinginwealth,whichenablesthefarmerto
(cid:35) makesomeadditionalnetinvestments.
o If RA > ST, then the production unit is increasing in wealth, which enables the farmer to 
If RA < ST, then the production unit is even less able to make any additional net
make some additional net investments. 
(cid:35) investments,andcannotevenentirelyrenewitsmeansofproductionandremunerateits
o If RA < ST, then the production unit is even less able to make any additional net investments, 
labourpoweratthemarketprice. Suchafarmisincrisis,losingassetsandfacingbasic
and cannot even entirely renew its means of production and remunerate its labour power 
needs;intheend,itmaydisappear,shifttoanotheractivity(labourersmovingtowealthy
at the market price. Such a farm is in crisis, losing assets and facing basic needs; in the end, 
neighbouringfarms),ortheownermaychoosetomigrate.
it may disappear, shift to another activity (labourers moving to wealthy neighbouring 
farms), or the owner may choose to migrate. 
Intheevaluationofthis“survivalthreshold”(perworkingpersonandperpersontofeedwithin
tIhne thfaem evilayl)uwateioans koefd thfiasm “isluyrmvievmalb tehrrseswhhoaldt”th (epierrb wasoircknineegd psewrseorne afonrda pgeirv peenrsyoenar t.o feed within 
the family) we asked family members what their basic needs were for a given year. 
• Theregionalopportunitycostoflabour: informsabouttheeconomicinterestfarmersmayhave
 iTnhde erdeigciaotninagl otphpeiorrwtuonriktyt ococsut rorfe nlatbporuord: uincftoiornmssy asbteomut othrea epcoosnsoibmleics ihnitfetrteosta nfaortmheerrsc ommayp ehtainvge 
ainct diveidtyic(aet.ign.g,u trhbeairn wmoigrkra ttoio cnu)r.rent production system or a possible shift to another competing 
activity (e.g., urban migration). 

FFiigguurree 55.. PPrroodduuccttiioonn uunniittss iinn ddeevveellooppmmeenntt aanndd pprroodduuccttiioonn uunniittss iinn ccrriissiiss wwiitthhiinn tthhee ssaammee aaggrraarriiaann 
ssyysstteemm ((aaddaapptteedd ffrroomm [[22]])).. 
3. Results
Agriculture2017,7,59 10of25
3. Results
3.1. HistoryandMainFeaturesoftheAgrarianSystem
3.1.1. OriginalEcosystem
Beforeagriculture,thevegetationofthecoastlinebetweenDakarandSaint-Louiswasarelicof
Guineanvegetation,alsoexistinginthesouthofthecountry[13,25]. ThisdistinguishestheNiayes
vegetationfromthatofthesamelatitudeinSenegal. Archaeologicalwork,beingrare,doesnotallow
researcherstogetprecisedataontheoriginsofagricultureinthisarea[26]. UsingasabasisArabicand
Portuguesetravellers’narratives,itcanbesaidthattheNiayeswasunoccupiedinthe15thcentury,
butwasvisitedbySererpopulationsextractingpalmwine,oilsandoinmentsfromElaeisguineensis
Jacq. palmtrees[27].
3.1.2. SettlingProcessesandPre-ColonialAgriculture
Thefirstmostimportantsettlementsstartedinthe13thcentury. Thissettlingprocesswouldbe
subjecttosuccessivemigration[28–30]:
• IntheSouthernpart,atemporaryMandingoccupationbeforethe13thcenturyandundoubtedly
followingtheGhanaEmpiredislocation. Intheirraidtothesouth, theysettledaroundMont
Rollandinthe13thcentury,wheretheypracticedshiftingagricultureandpalmtreeexploitation
incoast. Lebouspracticedcoastalfishing.
• Inthenorthandcentre,towards1680,FulafromSenegalRiver(Waalowaalbes)andfromtheedge
ofthecurrentLouga(Jeerinkkobes). Hamletswereestablishedalongthecoastbypopulationswho
alreadyknowtheareaduetotranshumance: theNiayesprovidespastureinthedryseason.
• Allalongthearea,Wolofs,afteratemporarypresenceregulatedbyseasons,wereinstalledinthe
18thcenturytoescapeinstabilityintheJoloof kingdomandslaveraidsintheWalo,Cayorand
Baol. Theyoccupiedtheregionwithoutestablishedrulesandpracticedshiftingagriculture(millet,
peanutwith15yearsoffallowlands).
3.1.3. Pre-ColonialAgriculture(Before1885)
Oilpalmexploitationinthexourbasin(areaDintheFigure2)isundoubtedlythemostancient
methodofagriculturallanduseintheNiayes. Thepeoplepracticedaneconomyofgathering,which
provided in small quantities fruit, wine and produce for basket-making [31]. In the central and
southernNiayesareas,thefirstemigrationwavesofLebouandSererbroughtsedentaryagriculture
to the area. This was an itinerant slash-and-burn agricultural system with exploitation of the dry
AcaciaseyalforestintheDieriarea(H)betweenDakarandThies[31,32]. Withthisself-subsistence
agriculture,prioritywasgiventofoodandtextilefibres’supply. Untiltheearly19thcentury,themain
cropswere: thevouandzou(VoandzeiasubterraneanL.),richinproteins;sesame(SesasumindicumL.),
whichweregrainsrichincalciumandgrilledforconsumption;sweetmelon(ColocynthiscitrullusL.),
rustic,oflargesizecalledbéref inSererandWolof;cassava(ManihotesculentaCrantz),ofanAmerican
species;andafewshrubbycottonplants(GossypiumhirsutumL.). Itcannotbeexcludedthataround
humidbasinsflood-recessionkitchengardenshaveexistedandplantedwithsweetpotatoes(whichis
alsoAmerican),Africanriceandgombo). Fulatranshumanttravelledregularlytothenorthernarea,
wheresomeFulahamletswereestablished.
3.1.4. IntroductionofNewCulturesbyColonialAdministration
Thecreation,inthe17thcentury,oftheSaint-Louistradingpostand,inthe19thcenturyofRichard
Toll’sexperimentgardensmarkedadeterminationtodevelopcolonialagriculture. Numerousfruits
andvegetableswereexperimentedwithatRichardToll’sandGorée. InSenegal,peanutcultivation
organisedbyagriculturalservicesstartedintheCapeVerdePeninsulainthe19thcentury. TheDieri