Reclaimed water use in biofuel production

Wa e 2015, 7, 4848-4857; doi:10.3390/w7094848 wa e ISSN 2073-4441 www.mdpi.com/jou nal/wa e A icle Reclaimed Wa e Use in Bio uel P oduc ion Ma ía del Pino Palacios-Diaz1,†,*, Vanessa Mendoza-G imón 1,†, Idai a He nández B i o 2,†, Juan Ramón Fe nández-Ve a 2,† and José Manuel He nández-Mo eno 3,† 1 Dp o P oducción Animal, G upo In es igación GEOVOL, Uni e sidad de Las Palmas de G an Cana ia, Fac. Ve e ina ia, A ucas 35013, Spain; E-Mail: .mendozag imó[email p o ec ed] 2 Labo a o io Ag oalimen a io y Fi opa ológico del Cabildo de G an Cana ia (Ag i-Food and Phy opa hological Labo a o y); A ucas 35013, Spain; E-Mails: ihe nandezb@g ancana ia.com (I.H.B.); j e nande[email p o ec ed] (J.R.F.-V.) 3 Depa amen o de Biología Animal, Eda ología y Geología, Uni e sidad de La Laguna, San C is óbal de La Laguna 38200, Spain; E-Mail: [email p o ec ed] † These au ho s con ibu ed equally o his wo k. * Au ho o whom co espondence should be add essed; E-Mail: mp.pal[email p o ec ed]; Tel.: +34-928- 454-353; Fax: +35-928-451-142. Academic Edi o : Ashok K. Chapagain Recei ed: 13 Ap il 2015 / Accep ed: 6 Augus 2015 / Published: 4 Sep embe 2015 Abs ac : Ja opha cu cas L., a oxic species ha does no in e e e wi h he ood chain, p oduces biodiesel o be e en i onmen al quali y han mine al oils. Howe e , in o de o cul i a e i sus ainably, i is necessa y o op imize he limi ed esou ces used, mainly wa e and soil. The e o e, in a id a eas, i is necessa y o cul i a e unde in ensi e condi ions, i iga e wi h eclaimed wa e and cu p oduc ion cos s. To op imize wa e consump ion, pa ial oo -zone d ying (PRD), which keeps a pa o he oo sys em d y, was used. This wa e managemen s a egy, employed success ully in o he oil c ops, yielded less ui pe bunch, bu mo e ui bunches pe plan . This ac will p obably allow o es ablish highe plan ing densi y and, consequen ly, highe p oduc i i y pe su ace uni . This is one o he ew a ailable op ions o imp o ing p o i abili y as p oduc ion pe ee is s able (1.25 kg seed plan −1 yea −1 o he mos p oduc i e ees, wi h excellen clima e and soil, and no limi a ions wa e use). A high pe cen age o ui lying on he g ound (24%) and non-uni o m iming in ui p oduc ion (excep some specimens) g ea ly hinde i s mechaniza ion. Al hough his c op’s en i onmen al and socio-economic bene i s a e no aken in o accoun , i is e y di icul , wi h only he calcula ed wa e consump ion (15.5 m3 OPEN ACCESS Wa e 2015, 7 4849 wa e pe L o oil o 5.6 m3 wa e pe L o oil acco ding o ou bes es ima ions), o conside i a p o i able op ion. Keywo ds: Ja opha cu cas; wa e consump ion coe icien ; pa ial oo -zone d ying (PRD); biodiesel; subsu ace d ip i iga ion (SDI) 1. In oduc ion Cul i a ing Ja opha cu cas L., a oxic species ha does no in e e e wi h he ood chain, can p o ide enewable uel o he anspo sec o , a sec o ha accoun s o one hi d o ene gy consump ion in Spain [1]. Howe e , in o de o o e a sus ainable solu ion, uncon en ional wa e esou ces mus be used, which a oids compe i ion o “g een wa e ” (e ec i e ain all), and “blue wa e ” (su ace and g oundwa e ). Soil, a limi ed, non- enewable esou ce, is ano he p oduc i e ac o o be op imized i we wish o ind an en i o- iendly solu ion. The e o e, he in ensi e cul i a ion o his species by using eclaimed wa e and i iga ion echniques o achie e op imized p oduc ion is he only op ion ha has appea ed in de eloped coun ies. Ve y li le in o ma ion is a ailable abou how o add ess Ja opha cu cas cul i a ion unde hese pa icula condi ions because i s high gene ic a iabili y [2] makes ca ying ou such s udies di icul . None heless, some ecen publica ions ha e p o ided in o ma ion on i s esponse o d ip i iga ion wi h eclaimed wa e [3,4] unde d y condi ions. Cos -bene i s udies ha e es ima ed J. cu cas p oduc ion cos s o be be ween 3 and 10 imes he e enue gene a ed by selling diesel in cul u al p ac ices in de eloping coun ies [3], so educing hese cos s is essen ial. Ye he li e a u e o e s no s udies in o in ensi e p oduc ion cos s. Mo eo e , a global analysis should in oduce he associa ed en i onmen al (pa icula es a e 80% cheape han hose p oduced by mine al uels [5], ca bon emissions a e lowe , isk o e osion dec eases when soil is cul i a ed, e c.) and economic ( inancial esou ces and economic ac i i y a e used and gene a ed in he coun y, which lowe s he ade de ici ) bene i s. Pa ial oo -zone d ying (PRD), a echnique ha has been de eloped based on knowledge o he physiological mechanisms ha con ol plan anspi a ion and oo -shoo signaling unde wa e sho age condi ions, consis s in i iga ing only one side o he oo zone so ha he plan can be simul aneously exposed o bo h we and d y soil [6]. This echnology, which was de eloped in he 1990s in Aus alia, o e s h ee bene i s: inc eased wa e use e iciency wi h no loss o yield; educed ege a i e g ow h (imp o ed ep oduc i e/ ege a i e balance); and imp o ed ui quali y [7,8]. Al hough he e a e no s udies ha ha e analyzed he esponse o PRD in Ja opha cu cas, he esul s ob ained o ano he oil ui , oli e, and explained by he bes s oma a closu e when PRD [9] is used, led us o conclude ha i would be possible o inc ease i s oil yield [6]. This pape analyzes he easibili y o using an i iga ion managemen echnique (PRD) o imp o e wa e p oduc i i y by p o iding da a o ad ance he s udy o he economic iabili y o Ja opha cu cas p oduc ion. Wa e 2015, 7 4850 2. Me hodology 2.1. Expe imen al Design and I iga ion Sys em Desc ip ion Fo his expe imen , a Ja opha cu cas plan a ion was used, which was se up 5 yea s ago on he g ounds o he Ag icul u al Expe imen al Fa m o Cabildo de G an Cana ia (Cana y Islands), wi h a plan ing ame o 3 m be ween aisles and 2.5 m be ween ees. In ea ly Feb ua y 2014, ees we e p uned wi h a chainsaw, which le ee heigh a 1.30 m and a c own diame e o app oxima ely 0.75 m. Then new specimens we e plan ed be ween ees in he old aisles (a a dis ance o 1.5 m) o lea e new aisles o 2.5 m. Howe e , his s udy only p esen s he da a o he ma u e ees. A he end o Feb ua y 2014, a subsu ace i iga ion sys em was bu ied 0.2 m deep o eplace he p e ious su ace d ip i iga ion. A se e e cochineal a ack mean wo pes icide ea men s had o be applied using summe mine al oil. No mo e pes s o diseases we e obse ed abo e he ea men h eshold. The soil o his land is classi ied as An h osol [10] (ISSS/ISRIC/FAO, 1998) o To ia en [11]. The o cha d has an au oma ic wea he s a ion, used o calcula e e e ence c op Penman-Mon ei h’s e apo anspi a ion (ET0) wi h da a a ailable since 2000. A p oblem occu ed in his wea he s a ion in 2014, which mean ha we we e only able o ob ain p ecipi a ion da a o 5 mon hs (Ap il–Augus ), du ing which ime accumula ed ain all was low, and he a e age alue o 2000–2014 was no dis inguished (26.6 L/m2) om he 22.7 L/m2 collec ed du ing his pe iod, while annual p ecipi a ion was 196 L/m2. The 248 m2 plo was di ided in o h ee blocks (each line o ees cons i u ed one block), in which he wo ea men s we e applied: a con ol (Tc), which consis ed in applying a daily dose o 2.6 L/m2; a second ea men (Ta), which ecei ed he same dose, bu was i iga ed al e na ely (weekly) on ei he side o he ees. A line o i e ees wi h 12 emi e s/ ee was i iga ed in each block; hus, each ea men i iga ed h ee lines o i e ees each, and each ea men consis ed in 15 ees dis ibu ed in o h ee lines: A, B and C (Tc) and D, E and F (Ta). A subsu ace i iga ion sys em (SDI) wi h in eg al d ippe s, p essu e-compensa ing a ange 1.5–4.0 ba , an i-siphon and high an i-d ain mechanism, spaced a 0.5 m wi h deli e y a es o 2.5 l hou −1, was used o apply eclaimed wa e . I iga ion lines we e spaced a 1.2 m, which le ees in he cen e . I iga ion ime was adjus ed o apply a cons an daily dose o wa e (wi h i iga ion wice daily) o ma ch he e e ence c op e apo anspi a ion (ET0) a e age measu ed in he las 14 yea s. Then wo i iga ions/day we e o ganized, and each i iga ion las ed 20 min o Tc ( he wo lines simul aneously i iga ed he same ee) and 40 min o Ta, bu only one o he lines i iga ed each ee (pa ial oo d ying “PRD”). Each subuni had one lowme e and eadings we e aken weekly. 2.2. Soil, Plan Analysis and Yield-Rela ed Pa ame e s Composi e soil samples be ween 0 and 0.2 m deep we e aken, which coincided wi h he beginning o he expe imen : 0.2 m apa om ee unks (in he we bulb, loc 1), be ween wo ees o each line (loc 2) and in he aisles (loc 3). A d y combus ion echnique was used wi h a LECO CNS 2000 analyze o de e mine o ganic ca bon (CO, as a %) and o al ni ogen (N o ). Soluble sal s we e es ima ed by elec ical conduc i i y (EC) a he 1:5 soil/wa e a io, exp essed in (dS/m) 1:5. A ailable ni a e (mg/kg) was de e mined by ex ac ion wi h 0.01 M calcium chlo ide and was hen analyzed by ion ch oma og aphy. A ailable phospho us (P, mg/g) was de e mined by he me hod o Olsen and Wa e 2015, 7 4851 Somme s [12]. Exchangeable ca ions we e ex ac ed wi h an ammonium ace a e solu ion bu e ed o pH 7. Ex ac ed ca ions (exp essed in meq/100 g), po assium (K), calcium (Ca), magnesium (Mg) and sodium (Na) we e analyzed by op ical emission spec opho ome y (ICP_OES). Composi e samples o young lea es we e aken om each ee line. N (%) was de e mined by he d y combus ion LECO CNS 2000 echnique. Fo he o he analyzed elemen s P, K, Ca, Mg, Na (exp essed in %), B, Cu, Fe, Mn and Zn (in mg/kg), he diges ion echnique was adop ed using ni ic acid in a mic owa e o he ICP_OES and subsequen analyses. The ipe ui s o each ee used in he di e en ea men s and he ui s ound on he soil we e collec ed weekly o 15 weeks. The ollowing pa ame e s we e measu ed in he ield: numbe o ma u e ui pe bunch and numbe o bunches wi h ipe ui ( e ile bunches), o each ee a each collec ion ime. F om he ob ained da a, he ollowing pa ame e s we e calcula ed: numbe o ha es ed ui pe ee (by adding hose collec ed om ees and hose ound on he soil). In he labo a o y, he ipe ui s and seeds o each ee and each ha es we e weighed. Also o each ee, wo new a iables we e calcula ed: accumula ed numbe o ui s pe bunch and accumula ed seed p oduc ion o e ime. 2.3. S a is ical Analysis An analysis o a iance (ANOVA) was ca ied ou wi h he SPSS s a is ical package ( e sion 22) using he gene alized linea m. The dependen a iables we e ea men (PRD: Ta s. Tc), collec ion da e and ee, including he analysis o he ollowing pe o mance pa ame e s: numbe o ui pe bunch, numbe o bunches wi h ipe ui pe ee ( e ile bunch/ ee), o al numbe o ma u e ui (including allen ui ) and numbe o ui collec ed om he ee op, weigh o he yield ob ained pe ui and seed (exp essed in g DM/ ee), and amoun o wa e applied (Tc and Ta) and hei in e ac ion. Mean sepa a ion was es ed by leas signi ican di e ence (LSD) a e se ing he signi icance le el a α = 0.05. The esul s we e agg ega ed o cumula i e p oduc ion. 3. Resul s and Discussion Ja opha is a species ha ole a es d yness, bu adequa e p oduc ion is no possible i i does no ecei e enough wa e . I needs an annual minimum o 500–600 L/m2 o app op ia e lowe ing and se ing [13]. As in all semia id egions, 196 L/m2 pe yea is insu icien , and i iga ion mus be used in hese zones [14]. Annual ain all mus each 1000–1500 L/m2 o achie e accep able p oduc ion wi hou i iga ion [15]. The amoun o wa e supplied du ing he expe imen al pe iod was 2.6 (L/m2·day−1), and wa e consump ion was measu ed om he lowme e eadings a 680 L/m2. The mon hly amoun o wa e used, compa ed wi h mon hly e apo anspi a ion (ET0) om Feb ua y o No embe 2014 (which was simila o he 14-yea a e age ET0), was 961 mm e sus 1015 mm, which was highe in au umn, bu lowe in summe and au umn 2014 (Figu e 1). The applied dose (assuming no p ecipi a ion) con ibu ed be ween 65% and 110% o he measu ed daily ET0 o 2014. Rega ding he esponse o clima ic ac o s, he daily a e age minimum empe a u e o he a ailable pe iod was always abo e 10 °C. The e o e, empe a u es coincided wi h op imal c op g ow h condi ions (20–28 °C, [16]). Wa e 2015, 7 4852 0 20 40 60 80 100 120 1.8 2.1 2.4 2.7 3.0 3.3 3.6 3.9 4.2 Jan Feb Ma Ap May Jun Jul Ago Sep Oc No Dec I iga ed wa e /ETo (%) ETo (Lm-2) Daily ETo Daily ETo_2014 I iga ed wa e /ETo Figu e 1. A e age e e ence c op e apo anspi a ion (ET0) o a ailable 14 yea s (g een), daily ET0 om he expe imen al pe iod 2014 ( ed) and i iga ed wa e /ET0 in % (blue). The soil samples esul s a e p esen ed in Table 1. Signi ican di e ences we e ound in almos all he pa ame e s acco ding o he sampling si e. In loc 1, a signi ican ly highe basici y was obse ed. Signi ican ly highe Ca and Na con en s, bu lowe salini y, OM, C/N, P, K and Mg, we e also ound. Despi e no being signi ican , he ni a e alues we e lowe in bulbs, which can be accoun ed o by g ea e nu ien abso p ion om he oo s ha g ew p e e en ially in he a ea. The e o e, he soil explo ed by oo s mos ly had a basic cha ac e , no salini y p oblems, a high OM con en and a e y s able cha ac e . Table 1. Means pH alues in wa e (1:2.5), elec ical conduc i i y 1:5 (EC in dS/m), lime, o ganic ma e (OM, exp essed as a %), o al ni ogen (N o , exp essed as %), a ailable ni a e (exp essed as mg N/kg), Olsen phospho us (exp essed as mg P/kg), ex ac ed ca ions (exp essed as me/100 g): po assium (K), calcium (Ca), magnesium (Mg) and sodium (Na) o he h ee sampling loca ions: (1) we bulb; (2) be ween lines; (3) be ween aisles. Loc pH EC Limes one OM N o C/N Ni a e P K Ca Mg Na 1 med 8.52 0.31a 5.05a 5.29a,b 0.33b 9.38a 109.18a 53.42a 4.47a 24.80c 7.54a 3.35b s d 0.037 0.08 0.17 0.18 0.01 0.16 136.86 4.38 0.26 0.48 0.12 0.19 2 med 8.37b 0.51a 5.91b 5.66b 0.34b 9.78a,b 384.1a 65.06b 8.40b 22.92b 9.33b 2.58a s d 0.041 0.09 0.19 0.20 0.01 0.18 151.61 4.85 0.29 0.54 0.13 0.22 3 med 8.11a 1.08b 5.87b 4.87a 0.29a 9.97b 1261.05b 64.64b 8.93b 21.25a 9.1b 3.2b s d 0.046 0.10 0.21 0.22 0.01 0.20 167.62 5.37 0.32 0.59 0.14 0.24 No e: Di e en le e s in supe sc ip ollowing alues (a, b, c) indica e s a is ical signi icance. Rega ding lea pa ame e s, he Ta plan s exhibi ed signi ican ly highe con en han he Tc ones, bu only o Na+. The mac onu ien con en s o he plan s used he ein ell wi hin he same ange as o he au ho s ha e epo ed (Figu e 2). Do a-San os [4] s a ed ha no p oduc i i y cons ain s occu ed wi h he nu ien con en s in he young lea es ha hey ob ained. Howe e , he K con en ob ained in ou expe imen was below ha epo ed in [4] and [17], bu simila o ha ob ained by [18] and [19]), and may be associa ed wi h p og essi e soil K deple ion in we bulbs (Figu e 2), in which no K e iliza ion was applied. Do a-San os [4] ound ha he soil pa ame e s which mos ly in luenced seed p oduc ion we e P and K. Gi en he ichness o ou soil P, K e iliza ion is ecommended. Wa e 2015, 7 4853 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 N o P K %This s udy La iola and Dias, 2008 [18] Chaudha y, 2008 [19] Souza e al, 2011 [17] de Miguel e al, 2013 [3] Do a-San os e al, 2014 [4] Figu e 2. Mac onu ien con en s in he lea es (%) ob ained he ein and hose epo ed by o he au ho s. When analyzing he esul s o ee a iables, we ound signi ican di e ences o numbe o ui /bunch. This esul ag ees wi h hose ob ained by [20] and [2], who obse ed di e ences when analyzing di e se Ja opha popula ions, al hough he ange o a ia ion indica ed by hese au ho s (0.2–9 and 6.6–12.3, espec i ely) was much wide han ha ound in ou ees. Signi ican di e ences we e also no ed in numbe o e ile bunch/ ee (pa ame e o which [2] ound no di e ences). A hi d pa ame e , numbe o ui / ee, which mus be added o he o he wo pa ame e s, also p esen ed signi ican di e ences, which again coincides wi h he indings o [20]. Howe e , no di e ences we e ound by [2]. In con as , a e age ui weigh did no signi ican ly di e among ees, and his esul also coincided wi h ha ob ained by [20], e en when a e age ui weigh (1.52 g/ ui ) was much lowe han ha ob ained in his expe imen (4.82 g/ ui ). These esul s con as wi h hose ob ained by Zegbe e al. [21], who s udied he in luence o PRD on yield, ui quali y a ha es , lesh i mness, o al soluble solids concen a ion, and many o he pa ame e s in apple ees. These au ho s ob ained he same alues be ween he con ol ea men and PRD, ye wa e use e iciency imp o ed by 120% in PRD ees. When he e olu ion o hese pa ame e s e sus ha es week (a e 15 weeks) was analyzed, di e ences we e ound in ou pa ame e s: numbe o ui /bunch (and wi h he ee a iable); a e age ui weigh (unlike ha ob ained o ees); and weigh / ee nu s and seeds, wi h highe yields ound be ween weeks 3 and 9. The wide a iabili y among ees coincided wi h [2], who s a ed ha lack o uni o mi y wi hin popula ions is one o he main p oblems o planning comme cial Ja opha p oduc ion. Thus, as he di e ences be ween ees we e so ma ked, i was di icul o obse e he e ec s o he s udied managemen p ac ices. Howe e , in his s udy we ound di e ences be ween Ta and Tc o wo pa ame e s, numbe o ui pe bunch and numbe o e ile bunches pe ee. Al hough Ta had signi ican ly less ui /bunch han Tc (2.5 s. 3.05, espec i ely), no signi ican di e ences we e ob ained o weigh o ha es ed ui . This esul ag ees wi h ha ob ained by [9] ia PRD echniques, who ound ewe , bu sligh ly la ge , oli e ui s. Ta had a signi ican ly highe a e age (14.88 e ile bunches/ ee) s. Tc (11.77). This indica es ha he smalle numbe o ui s pe bunch was compensa ed o by g ea e e ili y, which esul ed in he equi alen o al p oduc ion. This inding is p omising as i sugges s ha i Wa e 2015, 7 4854 plan ing densi y can inc ease, he ees i iga ed by an al e na e i iga ion me hod will be able o p oduce he same yield as hey p oduce mo e e ile bunches/ ee, despi e ha ing less space. This imp o emen in he balance be ween ege a i e g ow h and ep oduc i e de elopmen has al eady been epo ed in he i s s udies conduc ed in cul u ed PRD ines [6,7], which is one o he easons o imp o ed wa e e iciency in hese sys ems. The mean alues ob ained o he o he pa ame e s we e: pe cen age o ui allen on soil, 24%; a e age ui weigh , 4.82 g; weigh o p oduc ion ob ained o bo h ui and seed (148 and 63.66 g/ ee and ha es ing, espec i ely); and inally, 955 g seed/plan o 15 weeks, which coincides wi h [2] o imp o ed a ie y. Figu e 3 p esen s he cumula i e seed yield (exp essed as g DM/ ee) ob ained du ing he p oduc ion pe iod. Wide a iabili y among ees was obse ed, which was also he case be ween he less and mo e p oduc i e ees in he same line, and di e ences we e be ween 44% and 48% o Tc and Ta, espec i ely. Figu e 3b ep esen s he cumula i e p oduc ion o seeds o bo h ea men s. The ampli ude o he boxes co esponded o he ma ked di e ence among ees on he same ea men . Excep o a ew speci ic examples, we obse ed ha e y li le was ha es ed in mon h 1, and he same occu ed o he las ew weeks. Due o he wide a iabili y ob ained be ween indi iduals, we we e unable o dis inguish signi ican di e ences be ween Ta and Tc p oduc ion (1177 and 1173 kg/ha, espec i ely), which was less han 1875 kg/ha ci ed by [22] and [20]. We also saw ha ewe g o seeds we e ini ially ha es ed in Ta, bu he a e age ha es ed weigh since Oc obe was sligh ly g ea e . Whe he his end con inued o he ollowing yea mus be moni o ed. Some au ho s ha e ci ed ha oil yield om seeds was 28%, while Mo Fi [23] ci ed an oil yield o be ween 55% and 60% w/w, which coincided wi h he 55%–58% ound in he Cana ies, because hey exp essed his yield in whi e seed pe o mance e ms. When we ook he 35% /w alue as a e e ence, and assumed a densi y o 0.96 kg/L, i was possible o es ima e he i iga ion wa e equi ed o p oduce 437.5 L o oil pe ha by conside ing 6800 m3/ha o wa e used. Thus Ja opha needed 15.5 m3 o wa e pe L o oil ob ained. (a) (b) Figu e 3. (a) cumula i e p oduc ion o seeds h oughou he collec ion pe iod (g/ ee) o he h ee lines o each ea men (15 ees pe ea men ); (b) box-plo diag am o he cumula i e p oduc ion o seeds o bo h ea men s. Hence, he ob ained p oduc ion ha dly gua an ees p o i abili y o his c op. Indeed, by assuming a p ice o 0.2 € and 0.7 €/ L o wa e and oil, espec i ely, wa e expendi u e would mul iply he income ea ned om selling Ja opha by 4. Ye when we conside ed he p oduc ion o he bes ees Wa e 2015, 7 4855 (1.25 kg/ ee and yea ), and by assuming ha young ees ecen ly ini ia ed p oduc ion (2667 ees/ha), oil yield would be 1214 L/ha, which is he equi alen o 5.6 m3 wa e /L o oil, whe e wa e use would ep esen 1.6 imes he income made om selling he oil. Only o yields abo e 5000 kg o seed/ha, o i he p ice paid o he biodiesel was o e 0.7 €/kg, would Ja opha p oduc ion be in e es ing. Some au ho s [24] ha e ci ed a sales p ice o 5 $/kg o seed, which would ensu e p o i abili y. The e o e, in o de o imp o e p o i abili y, i is essen ial o educe he plan ing amewo k and inc ease he numbe o p oduc i e ees pe hec a e. I emains o be e i ied whe he oil con en is highe o he al e na e i iga ion me hod, as in oli es [6]. 4. Conclusions This s udy ob ained an a e age yield o 1200 kg seed/ha. Seed yield did no inc emen as a esul o al e na i e i iga ion (PRD). The a o emen ioned wide gene ic a iabili y o Ja opha plan s was e i ied, which makes conduc ing s udies in o op imizing ag onomic p ac ices di icul . Howe e , some pa ame e s we e a ec ed by he es ed wa e managemen as less ui pe bunch we e p oduced, bu he mos e ile bunch pe ee occu ed when plan s we e i iga ed al e na ely. The e o e by PRD, is i possible o inc ease plan ing densi y by main aining p oduc i i y/ ee since such managemen p o ides a la ge numbe o e ile b anches pe ee, which inc eases o al p oduc ion. In ac in o de o make Ja opha cu cas p oduc ion p o i able, educed spacing be ween ees is one o he ew op ions as p oduc ion pe ee is e y s able (1.25 kg seed/ ee in he bes young ees in his expe imen wi h excellen clima e and soil). Ano he ac o ha in luences p o i abili y is he la ge pe cen age o ui ha alls o he g ound (24%), so i is necessa y o collec i . Excep o a ew specimens, p oduc ion inc eased h oughou he p oduc ion pe iod, which made i e y di icul o imp o e he ha es ing p ocess using machine y. Wi h he calcula ed 15.5 m3 o wa e consump ion pe L o oil ob ained (5.6 m3 wa e /L acco ding o ou bes es ima ions once young ees s a ed p oducing), i is e y di icul o make his c op p o i able i he en i onmen al and socio-economic bene i s a e no conside ed. Acknowledgmen This wo k was suppo ed by Minis y o Economy and Finance (MINECO). Subp og am Basic Resea ch P ojec s (CGL2012-39520-C03-03) and FEDER. Con lic s o In e es The au ho s decla e no con lic o in e es . Re e ences 1. 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