A Partic ipatory Simulation to Fac ilitate Farmers’ Adoption of Livestock Feeding Systems Based on Conservation Agriculture in the Uplands of Northern Vietnam

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A Partic ipatory Simulation to Fac ilitate Farmers’ Adoption of Livestock Feeding Systems Based on Conservation Agriculture in the Uplands of Northern Vietnam

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A Partic ipatory Simulation to Fac ilitate Farmers’ Adoption of Livestock Feeding Systems Based on Conservation Agriculture in the Uplands of Northern Vietnam

IN TERN ATION AL JOURN AL OF AGRICULTURAL SUSTAIN ABILITY 1473-5903/ 04/ 02 0118-15 $20.00/ Vol 2, N o 2, 2004 # 2004 C Martin et al A Pa rtic ip a tory Sim ula tion to Fa c ilita te Fa rm ers’ Ad op tion of Livestoc k Feed ing System s Ba sed on Conserva tion Ag ric ulture in the Up la nd s of Northern Vietna m Ced ric Martin 1,2, Jean-Christop he Castella 2,3, H oang Lan Anh 2, Yann Egu ienta 1,2,4 and Tran Trong H ieu Centre d e Coop e´ration Internationale en Recherche Agronomiqu e p ou r le De´velopp em ent (CIRAD), Av Agropolis, 34398 Montpellier Ced ex 5, France; 2Mou ntain Agrarian Systems Programm e, Vietnam Agricultural Science Institute (VASI), Thanh Tri, H anoi, Vietnam; 3Institut d e Recherche p ou r le De´velopp em ent (IRD), 213 rue Lafayette, 75480 Paris Cedex 10, France, and International Rice Research Institute (IRRI), DAPO 7777, Metro Manila, Philip pines; 4Centre N ational d ’Etud es Agronomiques d es Re´gions Chau des (CN EARC), 1101 Av Agropolis, BP 5098, 34033 Montpellier Ced ex 1, France changes and p rioritising d evelop m ent issu es in Bac Kan, one of the p oorest p rovinces in northern Vietnam (Castella et al., 2003a) The d iagnostic p hase revealed three d riving forces for local d evelop m ent that are shared by m any other u p land areas in northern Vietnam and also by Southeast Asia in general First, the villagers’ access to markets, ed ucation, health services and technical information is of critical importance in p rovid ing d iversified local d evelop m ent op p ortu nities The geograp hic d iversity of the land scap e is reflected in the w id e d iversity of socio-econom ic environm ents (Donovan et al., 1997) Second , the su ccessive land p olicies that have accom p anied the p rocess of agricu ltu ral d ecollectivisation over the last d ecad e have been a m ajor d riving force of changes in land u se Land d istribu tion to ind ivid u al hou sehold s p rofound ly m od ified land -u se system s both in the valley bottom s and on the hillsid es (Castella & Dang, 2002; Jam ieson et al., 1998) Third , crop – livestock – forest interactions w ere com p letely transform ed by a changing econom ic context, and by accessibility and land tenu re p olicies The extensive m anagem ent of largeru m inants (bu ffaloes and cattle) has becom e a m ajor obstacle to agricu ltu ral intensification in both the low land s and the u p land s (Castella et al., 2003b; H u sson et al., 2001a) The restriction of the access bu ffaloes and cattle had to their trad itional forage resou rces resu lted in their straying into shru b- and forestland , cau sing p roblem s for forest regeneration and also for the anim als, as p oor d iet lead s to p oor p erform ance In recent years m ajor environm ental concerns In the m ou n tain areas of n orth ern Vietnam , exten sive h u sband ry of large-ruminants is limited b y the lack of n atural forage Since 2000, the M ou ntain Agrarian System Program h as b een cerned w ith this issue and h as evaluated techn ical altern atives aimed at sustainab le integration of crop-livestock systems O ne alternative sists of feed ing system s for largerum in an ts b ased on crop ping systems w ith p lan t cover D iffusion of information about the n ew system is sup p orted b y a set of interactive commu nication tools for u se b etw een farmers an d researchers A p articipatory simu lation m ethod w as d eveloped that com bines a comp artmental m od el of the village territory w ith five techn ical inn ovations Farmers sim ulate the ad op tion of the inn ovations they choose am on g food-forage cropp in g system s in rotation or in association, and u rea-treated straw They evaluate the q uan tity of forage that can b e grown for their h erd u sing the chosen set of techn iqu es Sim ulations revealed farmers’ straints and objectives in adoptin g sustainab le cropp ing systems on the h illsid es w hile main taining a small an im al h usban d ry system The results obtained b y each farmer p rovide a u sefu l b asis for d iscu ssion about the imp lemen tation of inn ovation This p articipatory simu lation m ethod cou ld b e m ore w id ely u sed to facilitate the d iffusion of inn ovations such as integratin g livestock feed in g system s w ith servation cropp ing p ractices Keyw ord s conservation agricu ltu re, livestock system s, m ou ntain areas, p articip atory sim u lation, Vietnam Introd uc tion Since 1997, the Mou ntain Agrarian System s Program has been investigating land -u se 118 Particip atory Sim u lation of Crop – Livestock System s in Vietnam have been raised abou t m ou ntain agricu ltu ral system s, concerns that em erged after the abolition of the agricu ltu ral collectives in 1988 Althou gh ou r research p rogram m e cou ld not go beyond the d ocu m entation of the im p act of accessibility and land p olicies on land -u se changes, w e d evelop ed a range of technical and organisational innovations to overcom e som e of the crop –livestock issu es that w e id entified A d iagnostic stu d y carried ou t beforehand set the stage for the d iffu sion of the innovations A large nu mber of cropping practices based on p lant cover and embracing the p rinciples of conservation agriculture w ere d eveloped as alternatives to slash-and-burn p ractices and tested in the real cond itions that the farmers face (Altieri, 2002; H usson et al., 2001b; Uphoff, 2002) These w ere d esigned as basic components of more comp lex cropp ing system s that farmers can combine in d ifferent ways d ep ending on their specific need s and objectives (e.g give p riority to rice sufficiency, crop –livestock association, p ut more emp hasis on forage for livestock, expansion of perennial crops, etc.) The m ost p romising innovations thu s far have been, (1) d irect sow ing of u pland rice or maize in a mulch of Brachiaria (grass) or M ucuna (legume), (2) crop –legume association (e.g cassava – Stylosanthes, orchard Arachis), (3) vegetative strips (natu ral vegetation, p lanted grasses or legumes) along contour lines, (4) a soil slow burning techniqu e that boosts the fertility of d egraded soils by releasing p hosp horu s in a form that the plant can easily u ptake, and (5) mini-terraces to control erosion on steep slopes In ad dition to restructuring soils, controlling erosion and improving crop m anagement, these innovations can also p rovide good quality forage for livestock (Eguienta et al., 2002) Farm ers w ho tested the p rop osed techniqu es in their ow n field s w ithin the fram ew ork of the p roject w ere very interested in these alternatives to trad itional slash and bu rn p ractices They su ggested im p rovem ents, and p rop osed som e of their ow n innovations (e.g treatm ent of straw w ith u rea) that w ere tested at a w id er scale in the p roject H ow ever, the d iffu sion of these new p ractices w as not an easy p rocess The sp ecific constraints of the m ou ntain environm ent had to be taken into accou nt in d esigning strategies for the d issem ination of innovation In m ost cases it is im p ossible for su bsistence farm ers to ad op t a com p lete p ackage; stepwiseadoption (i.e the introd u ction of su ccessive com p onents of a given cropp ing system s) is p referred The introd u ction 119 of any innovation is m anaged in a systemic perspective, as changes in the cropp ing p atterns of sm all u p land farm s inevitably affect livestock and forest resou rce m anagem ent For exam p le, the d evelop m ent of cover crops or vegetative strip s w ou ld lim it livestock access to fallow field s d u ring the w inter and w ou ld thu s requ ire farm ers (1) to fence their field s to avoid d am age to soil conservation crop s by straying anim als, and (2) to com p ensate for the restriction im p osed on trad itional forage resou rces by growing their ow n forage or p rovid ing access to other grazing areas The integrated com p onents of farm ers’ livelihood system s thu s cannot be stu d ied or m od ified ind ep end ently from each other Lastly, soil and w ater conservation techniqu es enable the highly d iverse u p land environm ent to be u sed to ad vantage In the face of the d iversity of situ ations and system s, a wide range of solutions is requ ired Farm ers can choose from am ong the op tions those that best fit their ow n p articu lar circu m stances and need s The above constraints in the d iffu sion of innovation call for an integrated m ethod ological ap p roach to farm ers’ livelihood system s and m ore sp ecifically to crop – livestock m anagem ent In su ch a d iverse natu ral and hu m an environm ent, only a p articip atory ap p roach is able to id entify farm ers’ need s in a tim e effective m anner (Castella et al., 2003b; N eef, 2004; Pretty, 1995) H ow ever, certain factors that ensu re the su ccess of the p articip atory m ethod (Mosse, 1994) have to be taken into accou nt w hen d esigning a m ethod that allow s farm ers to sim u late the ad op tion of innovation The p articip atory sim u lation ap p roach d iffers from a ‘rap id ’ ap p raisal that cannot resu lt in a fu ll u nd erstand ing of the com p lex system s involved nor establish a relationship of tru st betw een the local p op u lation and ou tsid ers Fu rtherm ore, a p articip atory ap p roach can accom m od ate d ifferent d egrees of p articip ation by p articip ants in a given session, and also d ifferent p ercep tions of the ap p roach by p articip ants (Moser, 1991) The facilitators of the m eetings m u st have good technical know led ge as w ell as good com m u nication skills to enable all the p articip ants to exp ress them selves Facilitators also need a good know led ge of the local context to be able to interp ret the inform ation generated by the ap p raisal, p articu larly the socio-p olitical asp ects, in ord er to avoid m isinterp retation (Sayer & Cam p bell, 2004; Shanks & Bu i, 2001) The tools (i.e tables, m ap s, figu res) u sed to generate this inform ation m ay be an 120 obstacle to active p articip ation if they are not easy to u nd erstand (Mosse, 1994) In ou r case, the sim u lation w as not carried ou t in ‘virgin’ territory bu t in a village w here p roject staff (inclu d ing one native of the village) had been exp erim enting innovations w ith local farm ers for the p ast three years This p rocess had resu lted in a good relationship betw een local stakehold ers and researchers and the latter had acqu ired a good know led ge of the local context In this pap er w e highlight the process of innovation d iffu sion that engaged both scientists and local stakeholders in d esigning a platform for social learning for the m anagem ent of natu ral resources (Roăling & Jiggins, 1998) The scientists facilitated the d iffusion of innovation by providing all the information needed to enable local p eople to m ake their own evaluation of crop–livestock issues, to collectively d iscover d ifferent possible solutions and to adap t them to the sp ecific issues they had d efined together To start the interactive comm unication p rocess w e d esigned a grap hic language to be used by scientists and local stakeholders The grap hic language incorporated tw o m ajor assum ptions d erived from p revious stu dies in the same area: (1) the village entity is the relevant sp atial and social u nit for comm unitybased management of natural resources (Castella & Dang, 2002), and (2) the spatio-temp oral d imension of crop –livestock interactions is a key factor to take into accou nt w hen d esigning or introdu cing technical innovations (Castella et al., 2002a) The aim of this p aper is to rep ort on our experience using and evaluating the new comm unication tool as a sup port for the d iffu sion of sustainable technical innovations The m ethod itself is d iscu ssed in d etail in two other p apers (Castella et al., 2002a, 2002b) The Suc c essive Stages in the Pa rtic ip a tory Sim ulation of Innova tion Adoption We p resented our grap hic models to rep resentatives of the local commu nity to check that we had in fact d esigned a ‘common spatial language’ betw een researchers and farmers The common spatial language is intend ed to p rovide a concrete supp ort for (1) the p articipatory valid ation of local information related to spatial management of natu ral resources, and (2) the introdu ction of technical innovations to imp rove feed ing systems for large rum inants Sixteen farm ers attended the International Jou rnal of Agricu ltu ral Su stainability first session held on 18 and 19 October, 2001 at the Phieng Lieng People’s Comm ittee The p articip ants w ere (1) rep resentative (men and w omen) of the three main household typ es classified in a household typology made in Phieng Lieng in 2000 (Eguienta et al., 2002); (2) knowled geable and influ ential p eople within the commu nity; and (3) farm ers w ho were familiar w ith the p roject activities and innovations through p reviou s involvem ent in project experiments At the beginning of the m eeting, the d ecrease in natu ral forage resou rces and the im p ortance of natu ral resou rce m anagem ent w ere highlighted At the first session, a 3D m od el of the village (Castella et al., 2002b) w as u sed as a visu al su p p ort to show the farm ers the m ain land scap e featu res and the d ifferent land -u se classes We established a link betw een the m ain land m arks on the 3D m od el and their rep resentation on a p ap er-based sp atial grap hic m od el Once the p articip ants w ere com fortable w ith the sp atial grap hic m od el that rep resented land u se in their village in 2001, w e u sed the sam e kind of grap hic rep resentations to show the changes in land u se that their village had u nd ergone over the last 40 years We w ere thu s able to show how cu rrent land u se and related issu es w ere a p rod u ct of the p ast (Castella et al., 2002b) At the end of the first session, a blank calend ar (Figu re 1) w as d isp layed so the p articip ants cou ld rep resent the d istribu tion of their activities over a p eriod of one year by d istingu ishing the relative contribu tion of m en and w om en and the location of the d ifferent activities in the village territory Eight activities w ere inclu d ed : irrigated rice, u p land crop s, orchard and gard en, anim al hu sband ry, gathering of tim ber and non-tim ber forest p rod ucts, and off-farm activities For each activity and gend er, the corresp ond ing w orking p eriod w as m arked on the calend ar Inform ation abou t annu al d istribu tion of labou r betw een activities and betw een m en and w om en is very im p ortant becau se lack of labou r can be a m ajor constraint in the ad op tion of innovations Interesting inform ation also cam e to light abou t interactions betw een crop and livestock related activities, show ing that the anim als relied exclu sively on natu ral resou rces or crop resid u es for forage: After each rice harvest, the ru m inants graze in the rice field s (N ovem ber – Decem ber and briefly in May –Ju ne) Particip atory Sim u lation of Crop – Livestock System s in Vietnam 121 Figu re Sp atio-tem p oral d im ensions of the sim u lation The only forage resou rce available in the crop p ing area d u ring the crop p ing p eriod is vegetation bord ering the field s and this is not su fficient Farm ers have to carefu lly m anage their stock of rice straw, w hich is d istribu ted to the w orking bu ffaloes d u ring the second rice cropp ing season At the second session, the sp atial m od el corresp ond ing to cu rrent land u se w as first p resented to the p articip ants and the sp atial com p artm ent m od el w as then introd u ced After the d ifferent com p artm ents had been d escribed , a p ap er cop y of the grap hic m od el of the village w as d istribu ted to each p articip ant w ho w as invited to locate his or her ow n land resou rces in the d ifferent com p artm ents N ext, five innovations w ere p rop osed together w ith their feed ing cap acity for large ru m inants Pap er cop ies of the com p artm ental m od el w ere u sed as su p p orts for a p articip atory sim u lation of innovation ad op tion The farm ers w ere then invited to choose am ong the p rop osed innovations the one they w ou ld like to ad op t, to locate it on the com p artm ental m od el, and w ith the assistance of the researchers, to calcu late the feed ing cap acity of their herd The p articip ants w ere alread y fam iliar w ith these new crop p ing system s as they had been tested by som e of them in their ow n village They w ere free to p rop ose their ow n innovations w ith the corresp ond ing technical p aram eters Mod elling Sp atia l Managem ent of Na tural Resourc es at the Village Level a nd Rela ted Livestoc k Ma na gem ent Issues The c om pa rtm ental m odel The d ifferent land -u se typ es in Phieng Lieng village territory w ere taken from a village scale GIS to create a com p artm ental m od el (Castella et al., 2002a), w here each kind of land -u se w as rep resented p rop ortionally This com m u nication 122 tool w as p resented to the farm ers attend ing the sim u lation p rogressively in d ifferent versions First, the sp atial m od el corresp ond ing to the cu rrent land u se (first level of abstraction) that had been show n to the farm ers at the p reviou s session w as d isp layed on a p ap er board Then the d ifferent elem ents of the sp atial m od el (Castella et al., 2002b) w ere id entified and p rogressively d raw n on a new schem atic m od el in ord er to lead the farm ers to a second level of abstraction: the com p artm ental m od el Once the schem atic m od el w as d raw n, a colou red version w as p resented w ith p rop ortions of land u se areas that show ed the real village situ ation (Figu re 1): the low land crop area m ainly corresp ond ed to 1– cycles of irrigated rice, som etim es m aize (hot rainy season) and vegetables (cold d ry season); the gard en area w as d ed icated to vegetables and fru it trees; the u p land crop area corresp ond ed to rainfed rice, m aize, cassava and p lantations; the term ‘forest’ inclu d ed p oor and second ary forests as w ell as w ood y regrow th Finally, each p articip ant received a sheet of p ap er show ing the village m od el on w hich they cou ld p osition their ow n crop and anim al resou rces along w ith the innovations they had chosen Sp a tio-tem p oral c onstraints linked to a nim a l husb andry Anim al hu sband ry issu es exist in the tw o d im ensions of sp ace and tim e At the beginning of the 1990s, the coop erative herd w as d istribu ted to ind ivid u als (one head /p erson) w ho each looked after their ow n anim al The forage resou rces that form ed the basis of this d evelop m ent w ere collective p astu res and the forest H ow ever, these areas w ere not controlled and natu ral resou rces grad u ally becam e insu fficient in term s of feed ing cap acity, cau sing tw o seriou s p roblem s that w ere inter-related : lack of forage d u ring the w inter (cold d ry season): forep art from a lim ited qu antity of d ried rice straw, natu ral vegetation w as the only feed ing resou rce available and its grow th w as near zero The resu lt w as w eakening anim als lead ing to a red u ction in fertility, abortion, d ecreased resistance to d isease and low w ork p erform ance at the beginning of International Jou rnal of Agricu ltu ral Su stainability the rainy season (first cycle rice p lou ghing/ harrow ing in March); intra- and inter-village conflicts: d u ring the w inter, starving anim als broke fences and d am aged crop s w ithin the village and d u ring the rest of the year they grazed in the neighbou ring village’s m ead ow To clearly illu strate the p roblem s cau sed by roam ing anim als, the m ovem ent of the village herd in the d ifferent com p artm ents w as illu strated on the m od el by arrow s (Figu re 2) The ad vantages and constraints of d ifferent solu tions for ind ivid u al and /or collective m anagem ent of the livestock herd w ere then introd u ced and d iscu ssed : closing off access to other village territories w ou ld be very d ifficu lt as it w ou ld requ ire fencing large areas in the u p p er p art of the village w atershed ; extend ing grazing in the collective area: the land cu rrently u sed cou ld only feed 12 bu ffaloes w hereas there w ere in fact m ore than 100 in Phieng Lieng Increasing the am ou nt of m ead ow land w ou ld requ ire collective m anagem ent or ind ivid u al u se of p lots in the collective area, neither of w hich w as consid ered feasible by the farm ers at the tim e; im p lem enting feed ing system s for largeru m inants by com bining innovative crop p ing system s in sp ace and tim e on ind ivid u ally ow ned land : this w as the solu tion chosen by the farm ers w ho agreed to sim u late the resu lts of su ch system s Results of the Partic ipatory Sim ulation Inp uts–outputs There w ere tw o sim u lation inp u ts: ad op ted innovation: each innovation has an associated yield and p eriod (w inter or su m m er); su rface area: 2000 m w as chosen as the u nit su rface area, as it is the size of the average p lot The ou u t is exp ressed as the nu m ber of equ ivalent bu ffalo (equ bu ) p er u nit area Fou r p aram eters w ere inclu d ed : p rod u ction p eriod , exp ressed in d ays (PProd ); consu m p tion rate for a given forage, ranging from to 10 (CR); Particip atory Sim u lation of Crop – Livestock System s in Vietnam 123 Figu re Discu ssion abou t a collective livestock m anagem ent p lan d aily theoretical m aintenance need s (MN ) for equ bu , exp ressed in kg DM/equ bu/d ay The average w eight of a bu ffalo is 300 kg and its d aily food requ irem ent is 2.5 kg d ry m atter (DM)/100 kg In ord er to take other anim als into accou nt, a cow is estim ated as 2/3 equ bu and a goat 1/10 equ bu ; p otential yield , exp ressed in kg/ha (PY) For a 2000 m p lot, PY CR/(PProd  MN ) ¼ n equ bu Orig in of the innovations and the m od el p a m eters The cropp ing system s w ith p lant cover sim u ltaneou sly enable su stainable agricu ltu re on slop ing land and im p roved anim al feed ing These techniqu es w ere first tested u nd er controlled cond itions on exp erim ental p lots hired from the farm ers Once valid ated in local cond itions, they w ere im p lem ented by farm ers on their ow n p lots w ith the assistance of technicians w ho collected the d ata and feed back from farm ers abou t the su ccess they had and the d ifficu lties they encou ntered w hile im p lem enting the new techniqu es At this p oint, five typ es of innovations had been selected in consu ltation w ith farm ers, each one sp ecific to an agro-ecological u nit (or com p artm ent of the village land scap e) Food -forage crop rotation (e.g three years of Brachiara sp then m aize) allow s feed ing of one bu ffalo/u nit area from March to N ovem ber Food -forage crop association: – Brachiara sp interlined w ith m aize allow s feed ing of half bu ffalo/u nit area from Au gu st to N ovem ber; – Stylosanthes guyanensis – cassava or orchard (p erennial system , one year settlem ent and w eed ing requ ired ) allow s feed ing of one bu ffalo/u nit su rface from March to N ovem ber; orchard soil covered by Arachis pintoă (p erennial system , one year settlem ent and w eed ing requ ired ) allow s feed ing of one bu ffalo/u nit area from March to N ovem ber; 124 International Jou rnal of Agricu ltu ral Su stainability u rea treated straw allow s feed ing of: – one bu ffalo/u nit area from Decem ber to March for m aize straw ; – tw o bu ffaloes/u nit area, sam e p eriod for rice straw Winter oats in the irrigated rice field s allow s feed ing of one bu ffalo/u nit area from Decem ber to March Valu es for p aram eters (Table 1) w ere estim ated from exp erim ental resu lts obtained in the Mou ntain Agrarian System s Program from 2001 to 2003 and from the literatu re (FAO) In ord er to be realistic and to highlight the constraints of innovative crop p ing system s, reference yield s corresp ond to m inim u m valu es obtained w ith a low level of inp u ts on p oor soils Du ring the d iscu ssion, inform ation abou t com p u ted yield s w as com p lem ented by inform ation abou t forage valu es d istingu ishing betw een p rotein and energetic forages (Figu re 3) and consid ering the biop hysical effects of the cover crop s: grasses w ith a d eep and strong root system , su ch as Brachiaria sp , p lay a key role in soil d ecom p action and in the im p rovem ent of p orosity; they also p lay the role of ‘biological p u m p ’ by recycling m inerals that are not accessible to associated or rotated crop s; legu m es, su ch as Stylosanthes and Arachis sp p , im p rove chem ical fertility of the soil by fixing atm osp heric nitrogen; u rea treatm ent of rice and m aize straw are alternatives to bu rning straw that help red u ce CO em ission w hile p rovid ing good qu ality feed for livestock; w inter oats crop p ing in p ad d y field is a p ossible first step tow ard m ore com p lex crop p ing system s associated w ith a living p lant cover A su bstantial increase in the soil organic carbon content in the 10 cm top soil layer in Figu re Forage valu es of som e grasses and legu m es tested (H u sson et al , 2003) no-tillage soils com p ared w ith soils u nd er natu ral vegetation and long-term conventional tillage (Se´guy et al., 2003) can occur d u e to high crop-resid u e inp ut and lack of soil d istu rbance Moreover, micro and macro-fauna populations, abundance, d iversity and soil biological activity d ecrease d uring traditional cu ltivation system s Conversely, the soil structure is improved w hen a vegetal cover with a strong root system is p ermanently maintained on the soil (H usson et al., 2003; Up hoff, 2002) Im plem entation of the sim ula tion Po sitio ning fa rm ers’ reso urc es on the m o d el Farm ers d rew lines on the grap hic m od el to show the land they ow ned or cou ld u se in each com p artm ent, i.e the lim its of their ind ivid u al land -u se system (Figu re 4) A table w as d istribu ted so each farm er cou ld note d ow n the size of his bu ffalo herd Tab le Valu es for p aram eters of the innovations u sed for the sim u lation Innova t ion Brachiaria rotation Brachiaria association Stylosanthes association P ot ent ia l yield (kg/ha ) P roduct ion period (da ys) Consumpt ion t e N equ.bu 2000 275 500 122 0.5 2000 275 Arachis-orchard 2000 275 Urea-treated rice straw 3600 121 2.5 Urea-treated m aize straw 900 121 Winter oats 900 121 Particip atory Sim u lation of Crop – Livestock System s in Vietnam 125 Figu re Positioning farm ers’ resou rces and innovations on the com p artm ental m od el Presenta tio n o f the inno va tio ns The innovations w ere p resented on a table (Figu re 5) giving p otential ou u ts (equ bu /u nit area) w ithin the p rod u ction p eriod along w ith sp ecific characteristics (settlem ent tim e, fertilisation and labou r requ irem ents, etc.), and illu strated w ith p hotos taken d u ring p reviou s exp erim ents in their village Cho ic e o f inno va tions b y the fa rm ers a nd eva lua tio n o f the results Coloured squares corresp onding to the d ifferent innovations w ere exp lained and then d istributed to the farmers w ho chose some of them and p laced them in the relevant comp artments on their schematic m od el A brief d em onstration showed them how to calcu late the nu mber of buffaloes fed 126 International Jou rnal of Agricu ltu ral Su stainability Figu re Discu ssions betqeen farm ers and researchers abou t the sim u lation in term s of feed ing cap acity d uring the d ifferent p eriod s of the year The result w as then transferred to the buffalo table In add ition to the d em onstration, it w as explained that: From Sim ulation to Ac tion Understand ing and disc ussing the m odel and proposed innova tions the feed ing cap acity linked w ith the innovation is only estim ated and in p ractice it m ay be slightly d ifferent; only the sim p lest and cheap est techniqu es had been p resented , and these w ou ld not be su fficient to feed all the bu ffaloes even if they w ere ap p lied to the w hole village territory; at this stage, the calcu lation d id not take labou r requ irem ents into accou nt Follow -u p visits (tw o sessions totalling five d ays, betw een the end of N ovem ber and the beginning of Decem ber) w ere m ad e to Phieng Lieng farm ers w ho had attend ed the sim u lation The aim w as to m aintain the farm ers’ interest in innovations initiated by the sim u lation, to check their u nd erstand ing of the m od el, and to get their p oints of view abou t the feasibility of the innovations The su rveys w ere cond u cted as op en interview s to: The farmers were then invited to make their own calcu lations based on their own sp ecific situation, w ith the assistance of the project staff, and to enter the result on their own table, enabling them to see if their w hole herd cou ld or could not be fed from their ind ividu al plots This triggered a lively d iscussion (Figure 5) At the end of the session they were remind ed that this w as only the first step in solving their problem, and they w ere encouraged to contact the team if they w ished to imp lement the proposed innovations listen to the farm er ’s com m ents abou t the m eeting and p articip atory sim u lation; check the farm er ’s u nd erstand ing of the m od el Before d iscu ssing the innovations the farm er w as interested in, he w as asked to d escribe the three m ain com p artm ents of the m od el, the location of his resou rces and the innovations he had chosen, in ord er to check his u nd erstand ing of the m od el and to clarify any p oints that had not p reviou sly been m ad e clear; Particip atory Sim u lation of Crop – Livestock System s in Vietnam d iscu ss the innovations chosen (constraints, p lans, etc.) All those interview ed exp ressed p ositive reactions to the m eeting Most of the p articip ants correctly u nd erstood the m od el and the sim u lation gam e This resu lt confirm ed their interest and ability to concentrate d u ring the testing of the m od el Farm ers’ com m ents, p lans and constraints abou t p ossible innovations and their ap p licability are p resented in Table The general colu m ns d escribe id eas for w hich there w as a consensu s in the com m u nity The sp ecific colu m ns are based on ind ivid u al com m ents m ad e by farm ers of each farm typ e classified by Egu ienta et al (2002) The lack of forage in w inter w as a m ajor constraint for m ost of the resp ond ents It has negative effect on p erform ance, rep rod u ction and resistance to d iseases In 2000 there w as an ep id em ic that led to the d eath of m any bu ffaloes Ap art from ind ivid u al activities, the p roject m ay assist the village in a collective activity p rop osed by one farm er to grow m u cu na on the collective p astu re area to regenerate the soil and overcom e w eed s Mu cu na is easily cleared and other crops can then be grow n The p roject cou ld thu s initiate a d ynam ic of collective m anagem ent that cou ld p artly com p ensate for p roblem s cau sed by ind ivid u al im p lem entation Many resp ond ents w ere w orried abou t the fact that forage crop p lanting tim e (March) m ay coincid e w ith the sp ring season There is a risk of a labou r shortage at this tim e and som e hou sehold s w ou ld thu s not be able to im p lem ent the innovations Very few of the farm ers interview ed w ere interested in rotating forage and food crop s They ap p eared to consid er it a w aste of land and to p refer associating these crops, w hich highlights the land satu ration situ ation Som e farm ers fear that u rea treated straw, esp ecially m aize straw, cou ld be d angerou s for their livestock Only a few farm ers w ere interested in grow ing w inter oats becau se the p ad d y field s are u su ally not fenced d u ring the w inter This absence of fencing is also a seriou s constraint for innovation im p lem entation in the hillsid es Most of the crop associations are p lanted in the resid ential/gard en area w here su rveillance is easier 127 Table show s the d iversity of the p articip ants rep resented by the w id e range of agricu ltu ral and anim al resou rces Farm ers’ strategies d u ring the sim u lation w ere influ enced by their available resou rces, cap abilities and objectives, resu lting in a w id e range of reactions and innovation choices (Figu re 6) The objectives of their anim al hu sband ry activities d iffered as a fu nction of their ind ivid u al circu m stances These can range from ow ning a cou p le of bu ffaloes for land p rep aration in the p ad d ies, to d evelop ing a living cap ital, p rod u cing m eat or d iversifying sou rces of incom e All these p aram eters influ enced the farm ers’ interest in the sim u lation, their choice of innovations, and their m otivation to actu ally im p lem ent the innovations For instance, som e farm ers w ho d id not ow n large ru m inants also p layed the gam e, either becau se they p lanned to bu y an anim al or becau se they w ere interested in the soil fertility im p rovem ent fu nction of the techniqu es, or in the feed ing valu e of the cover p lants for fish farm ing It can also be seen that som e constraints affect the w hole com m u nity w hile others are sp ecific to som e hou sehold s: available labou r is a p roblem for som e farm ers, w hile for others it is the d isp ersion of their p lots or their rem oteness that p revents them from fencing The m ain ou tcom es of this exp erim ent in p articip atory sim u lation w ere first that farm ers w ere not p rep ared to collectively m anage forage resou rces at the village scale in ord er to feed their entire bu ffalo herd They p referred to rely p rim arily on the anim al feed they cou ld p rod u ce on their ind ivid u al p lots (Castella et al., 2002b) Second ly, cropp ing system s based on cover crops w ou ld be d evelop ed on the hillsid es only throu gh a step w ise p rocess that w ou ld solve the p roblem of forage d eficit d u ring the w inter before establishing cover crop s on the slop es and therefore avoid ing d am age by anim als to u p land field s N ew forage resou rces from the valley bottom w ou ld facilitate the introd u ction of the conservation cropp ing system s on the hillsid es Im plem entation of innovations The follow ing w inter season (2001), tw o innovations w ere p rop osed to the farm ers: u rea treated rice straw and w inter oats The aim of these tw o new com p onents in the livestock feed ing system s w as to low er anim al p ressu re on the new cover crops on the hillsid es as w ell 128 Tab le Synthesised inform ation from farm er interview s (su rvey d ata) The general colu m ns d escribe id eas for w hich there w as a consensu s in the com m u nity The sp ecific colu m ns are based on ind ivid u al com m ents m ad e by farm ers in the ind icated categories Type/husba ndry Comment s Genera l N o bu ffaloes Bu ffaloes for labou r Cap italisation (bu ff and /or ox) Presentation u sefu l for: † know ing history; † long-term strategy bu ild ing; † u nd erstand ing the lim its of natu ral forage resou rces; † know led ge of constraints and their resolu tion Diversification (bu ff., ox, goat) P la ns Specific Interested by the d ou ble fu nction of cover crop s: feed ing ỵ soil restoration Exp ecting ind ivid u al allocations from collective area Const int s Genera l † Grad u al innovation im p lem entation (step w ise) † Using cover crop s also for fish and p ig feed ing Specific Anim als sold , som etim es rep laced by a cu ltivator; p lan to bu y – bu ffaloes Cow shed near the u p land field s Genera l † † † † † Storage for treated straw Unw illing to exp loit forest (labou r cost and conservation) † M ucuna in the collective area; † collective organisation † † † † † † † † Anim al m ortality; anim al labou r force Und erexp loited land ; Tim e for grass cu tting Livestock roam ing; p lot scattering and d istance; slop e Lack of agricu ltu ral resou rces; anim al w atching Tab le Basic statistics abou t som e farm ers’ agricu ltu ral and anim al resou rces (Source: Mou ntain Agrarian System s Program ) P a met er Mean Max Min No w orkers/ household 2.9 10 1.5 P a ddy a rea (ha ) Upla nd a rea (ha ) Forest la nd a rea (ha ) No buffa lo 3.186 2.918 8.081 3.8 6.750 10.000 20.000 15 1.500 0 590 No ca t t le 0.7 International Jou rnal of Agricu ltu ral Su stainability Cover crop ¼ com p lem entary fod d er Lack of fod d er, esp ecially in w inter; w eed control; fences (cost and efficiency); hu m an labou r force; inp u ts and know led ge: need for m aterial and technical assistance Specific Particip atory Sim u lation of Crop – Livestock System s in Vietnam 129 Figu re Exam p le of three contrasted ind ivid u al m od els (su rfaces  1000 m 2) as on the natu ral m ead ow and forest resou rces d u ring the w inter season Urea -trea ted ric e stra w Given farm ers’ relu ctance to treat m aize straw (consid ered u nsu itable for ru m inant feed ing), w e p rop osed u rea treatm ent of rice straw, w hich has three ad vantages: better conservation: u ntreated straw stock is som etim es d am aged by fu ngi, rats or insects; increased d igestibility: the treatm ent is in fact ‘p re-d igestion’ w hich enables the anim al to eat a larger qu antity; increased forage valu e Farm ers u su ally bu rned rice straw from irrigated field s after the au tu m n harvest and kep t a sm all qu antity w hich w as d ried and u sed as occasional fod d er d u ring the w inter Althou gh the ash w as then u sed to fertilise rice nu rseries, the net resu lt w as the exp ort of p lant m aterial from the field Exp orting rice straw for anim al feed thu s p rovid ing m anu re for low land rice field s is a m ore su stainable m anagem ent techniqu e Briefly, the techniqu e consists of cu tting d ry rice straw into segm ents (betw een 15 –25 cm long), w hich are m oistened w ith a 4% u rea w ater solu tion (betw een 80 –100% DM) and then salted (0.5– 1% DM) (N gu yen, 2004) Recom m end ations for the d u ration of ferm entation range from three to fou r w eeks This techniqu e w as introd u ced in three step s: p relim inary d iscu ssions w ith the farm ers w ho chose this innovation d u ring the sim u lation (12 farm ers) abou t their objectives and constraints; id entification of farm ers w illing to take p art in the exp erim ent and d em onstration of the straw p rocessing and the d istribu tion of treated straw to the bu ffaloes ow ned by the p roject (staff of the agricu ltu ral extension service w ere invited to p articip ate); d istribu tion of technical leaflet abou t the techniqu e of straw treatm ent w ith u rea 130 In the end , six of the 12 farm ers d id not im p lem ent this techniqu e d u e to insu fficient straw, lack of labou r (to cu t straw and d ig holes) or becau se they w anted to check the resu lts of this techniqu e w ith their neighbou rs before ad op ting it them selves The p roject assisted the six other farm ers w ith straw treatm ent They fou nd the techniqu e sim p le, cheap and not overly tim e consu m ing Winter o a ts in the p a d d ies Most of the farm ers d id not u se their irrigated rice field s d u ring the w inter (thou gh a few grew vegetables on sm all areas p rotected by bam boo fences) They u su ally p lou ghed and then flood ed their field in Decem ber – Janu ary (d ep end ing on available labou r) in ord er to p rep are it for the first crop of rice as soon as the rainy season begins It w as su ggested to these farm ers to grow oats in these field s to cu t as green forage d u ring the w inter The id ea w as to organise the field into d aily cu tting p lots in su ch a w ay that the first p lots had su fficiently regrow n w hen the last p lot had been cu t, as a fu nction of the nu m ber of anim als to be fed , the qu antity requ ired p er anim al and the sp eed of oat regrow th u nd er the local cond itions If the farm ers d id not have a big enou gh rice field , a com bination of oats, natu ral vegetation, and u rea treated rice straw w as d eterm ined w ith them as feed ing system com p onents to im p rove w inter feed ing Du ring the sim u lation, only three farm ers chose this innovation both becau se of the fencing constraint (in w inter, anim als roam in the p ad d ies) and becau se of the novelty of this crop Finally, the p roject su p p orted the volu nteer farm ers by p rovid ing fencing and oats w ere sow ed d irectly u nd er the m u lch of rice straw The large qu antity of biom ass p rod u ced (around t DM/ha at flow ering) consid ering the season and the lack of forage at that tim e, w as su fficient to convince the farm ers In 2002 this activity exp and ed and inclu d ed other w inter cereals (w heat and barley) in the p ad d y field bu t also on the low er p art of the hillsid es Within one year, 80% of p articip ants had tested in real cond itions som e kind of innovative crop p ing system that they had d iscovered d u ring the sim u lation For exam p le, in Janu ary 2002, half the farm ers treated rice straw w ith u rea as a w inter fod d er com p lem ent The sim u lation revealed that this strategic su p p ly of im p roved fod d er m et the farm ers’ need s, and this led u s to p rovid e assistance to a larger nu m ber of International Jou rnal of Agricu ltu ral Su stainability farm ers in the w hole Cho Don d istrict Extension agents from the Agricu ltu ral Services of the d istrict w ere trained d u ring treatm ent of straw on the farm s, and the follow ing year, they trained farm ers in other villages in the d istrict Du ring the 2002 rainy season, half of the p articip ants im p lem ented other innovations on their slop ing field s (association Arachis pintoi -orchard , settlem ent of Brachiaria sp for forage p rod u ction, etc.) Conc lusions The p articip atory sim u lation p rovid ed m any new elem ents for agricu ltu ral d iagnosis and help ed u s im p rove the p rop osed crop – livestock m od el Farm ers w ere clearly interested in the p rop osed innovations and asked very relevant qu estions Du ring the follow -u p visits w e w ere able to confirm that farm ers w ere m ore aw are of local issu es related to crop –livestock interactions and w ere read y to u nd ertake concrete actions tow ard su stainability that they had encou ntered d u ring the sim u lation These resu lts show that the sim u lation w as effective in enhancing farm ers’ p articip ation in thinking abou t and in u nd ertaking action tow ard m ore su stainable cropp ing system s and anim al hu sband ry system s at field , hou sehold and village levels The m onitoring of innovation d iffu sion p rocesses p rovid es a basis to assess the effectiveness of the m od el itself It shou ld allow for sp ontaneou s ad ap tations as w ell as alternative sou rces of innovation p rovid ed by the farm ers them selves For instance, in other villages, som e farm ers hire w orkers to go farther into the forest to cu t and carry back natu ral grasses Others have their anim als tend ed by farm ers w ho are located w here su fficient forage is available Desp ite these encou raging resu lts, not all the farm ers ad op ted the innovations p rop osed Som e w ere p revented from d oing so by the technical skills requ ired by the new feed ing system s or by the inp u ts, p articu larly fencing w hich is exp ensive for the ind ivid u al farm er After this su ccessfu l test in real cond itions the m ethod w ill now be ap p lied to other villages in Bac Kan p rovince We need to test it in m any d ifferent natu ral and hu m an environm ents for fu rther valid ation In the fu tu re, it m ay be ap p lied on a rou tine basis by local extension agents So far, m ost of the p articip ants have been relu ctant to d evelop concerted ru les for Particip atory Sim u lation of Crop – Livestock System s in Vietnam com m u nity-based livestock m anagem ent Althou gh they are consciou s of the p otential benefits for the w hole village, setting u p the negotiation p latform has to go throu gh a p relim inary stage of ind ivid u al ad op tion, taking into accou nt the p articu lar circu m stances of each hou sehold Once farm ers have been convinced of their ind ivid u al benefit in ad op ting the technical innovations it w ill be easier to engage negotiations abou t organisational innovations to rationalise forage resou rce m anagem ent at the village scale Ou r p articip atory sim u lation m ethod p roved very effective in su p p orting ind ivid u al d ecision-m aking Fu rther d evelop m ent of ou r m ethod ology w ill aim at com m u nity-based m anagem ent of natu ral resou rces Regard ing the feed ing system s them selves, im p ortant w ork still rem ains to be d one, su ch as ad ap ting them to situ ation-sp ecific constraints and labou r allocation, and enabling farm ers to concretely im p lem ent the p rop osed innovations (seed s, environm ent-friend ly herbicid es, fencing, etc.) With this in view, socio-econom ic com p onents su ch as social netw orks, p olicies, and cred it have to be closely exam ined The feed back received from farm ers d u ring the p articip atory sim u lations w ill also help im p rove the technical innovations w hile taking into accou nt the socio-econom ic context of their im p lem entation Ac knowled g em ents The au thors w ou ld like to thank the Mou ntain Agrarian System s Program team m em bers involved in the sim u lation: H oang Van Viet, H oang H Bac, N gu yen H oang Mai, N gu yen Qu ang Tin, N gu yen Van Manh, Step hane Salim , Tran Thi H u ong Giang and Trieu Thi Vang The au thors are also very gratefu l to Pau l N ovosad for ed iting an earlier version of this p ap er Corresp ond enc e Any corresp ond ence shou ld be d irected to Jean-Christop he Castella, Institu t d e Recherche p ou r le De´ velop p m ent (IRD), B.P 64501, 34394 Montp ellier Ced ex 5, France (j.castella@ird fr) Referenc es Altieri, M.A (2002) Agroecology: The science of natu ral resou rce m anagem ent for p oor farm ers in m arginal environm ents Agriculture, Ecosystems and Environment 93, 1–24 131 Castella, J.C and Dang, D.Q (ed s) (2002) Doi M oi in the M ountains Land Use Changes and Farmers’ Livelihood Strategies in Bac Kan Province H anoi, Vietnam : The Agricu ltu ral Pu blishing H ou se Castella, J.C., Egu ienta, Y and Tran, T.H (2002a) Sp atial com p artm ent m od el: An interface betw een scientists and local stakehold ers to facilitate the d iffu sion of innovative livestock feed ing system s SAM Paper Series 13 H anoi: Vietnam Agricu ltu ral Science Institu te Castella J.C., Tran, T.H and Egu ienta, Y (2002b) Use of sp atial grap hic m od els as a com m on langu age betw een researchers and local stakehold ers SAM Paper Series 12 H anoi: Vietnam Agricu ltu ral Science Institu te Castella, J.C., Chabanne, A., Dang, D.Q., H a, D.T., H u sson, O., Le, Q.D and Tran, D.L (ed s) (2003a) Towards Sustainable Agricultural Development in M ountain Areas of Northern Vietnam Experience from the M ountain Agrarian Systems Program in Bac Kan Province, 1998–2002 H anoi: Vietnam Agricu ltu ral Science Institu te Mu ltim ed ia CD-Rom and Web site: w w w.know led gebank.irri.org/sam / hom e_en.htm l Castella, J.C., Boissau , S and H oang, L.A (2003b) Enhancing com m u nities’ ad ap tability to a rap id ly changing environm ent in Vietnam u p land s: The SAMBA role-p lay In R.C Serrano and R.T Aggangan (ed s) Sustaining Upland Development in Southeast Asia: Issues, Tools & Institutions for Local Natural Resource M anagement (p p 203–236) Los Banos, Philip p ines: PCARRD Donovan, D., Ram bo, A.T., Fox, J., Le, T.C and Tran, D.V (1997) Development Trends in Vietnam’s Northern M ountain Region An Overview and Analysis H anoi: N ational Political Pu blishing H ou se Egu ienta, Y.K., Martin, C., Lecom te, P., H u sson, O and Castella, J.C (2002) Crop -livestock in northern Vietnam : Issu es, d iversity of farm ers’ resp onses and alternatives for su stainable integration of anim als in u p land agricu ltu ral system s In J.C Castella and D.Q Dang (ed s) Doi M oi in the M ountains (p p 221–247) H anoi: The Agricu ltu ral Pu blishing H ou se H u sson, O., Castella, J.C., H a, D.T and N au d in, K (2001a) Agronom ic d iagnosis and id entification of factors lim iting u p land rice yield in m ou ntainou s areas of northern Vietnam SAM Paper Series H anoi: Vietnam Agricu ltu ral Science Institu te H u sson O., H a, D.T., Lienhard , P., Le, Q.D and Segu y, L (2001b) Agronom ic d iagnosis and d evelop m ent of d irect sow ing techniqu es Up land ricebased cropp ing system s in m ou ntainou s areas of northern Vietnam Contribution to the First World Congress on Conservation Agriculture, ECAF/FAO, 1–5 October 2001, Mad rid , Sp ain At w w w know led gebank.irri.org/sam /sam /p d f/2001_ PosterMad rid _E.p d f H u sson, O., Chabanne, A., H a, D.T., Lecom te, P., Martin, C., Castella, J.C., Tivet F and Se´ gu y L (2003) Integrating crop s and livestock throu gh 132 d irect seed ing on vegetal cover in Vietnam Proceedings of the II World Congress on Conservation Agriculture: “ Producing in harmony with nature” , Igu acu Falls, Parana, Brazil, Au gu st 11–15, 2003 (p p 357– 367) Ponta Grossa, Brazil: FEBRAPDP Jam ieson N , Le Trong Cu c, Ram bo A.T (1998) The Development Crisis in Vietnam’s M ountains H onolu lu : East-West Centre Mosse, D (1994) Au thority, gend er and know led ge: Theoretical reflections on the p ractice of p articip atory ru ral ap p raisal Development and Change 25 (3), 497–526 Moser, P.K (1991) Knowledge and Evidence Cam brid ge, N ew York: Cam brid ge University Press N eef, A (ed ) (2004) Participatory Approaches for Sustainable Land Use in Southeast Asia Bangkok: White Lotu s Pu blishers N gu yen, X.T (2004) An evalu ation of ad op tability of alkali treatment of rice straw as feed for grow ing beef cattle u nd er sm allhold ers’ circu m stances Livestock Research for Rural Development 16, 52 At http ://w w w.cip av.org.co/lrrd /lrrd 16/7/trac16052 htm Pretty, J.N (1995) Particip atory learning for su stainable agricu ltu re World Development 23, 1247 1263 Roă ling, N G and Jiggins, J (1998) The ecological know led ge system In N G Roă ling and M.A.E International Jou rnal of Agricu ltu ral Su stainability Wagem akers (ed s) Facilitating Sustainable Agriculture: Participatory Learning and Adaptive M anagement in Times of Environmental Uncertainty (p p 281–307) Cam brid ge, UK: Cam brid ge University Press Sayer, J and Cam p bell, B (2004) The Science of Sustainable Development: Local Livelihoods and the Global Environment Cam brid ge, UK: Cam brid ge University Press Se´ gu y, L., Bou zinac, S., Scop el, E and Ribeiro F (2003) N ew concep ts for su stainable m anagem ent of cu ltivated soils throu gh d irect seed ing m u lch based cropp ing system s: The CIRAD exp erience, p artnership and netw orks Proceedings of the II World Congress on Conservation Agriculture: “ Producing in harmony with nature” , Igu acu Falls, Parana, Brazil, Au gu st 11–15, 2003 Ponta Grossa, Brazil: FEBRAPDP Shanks, E and Bu i T.D (2001) Field Based Learning and Training in Participatory Approaches to Rural Development A Decade of Experience in PRA from the Vietnam Sweden Cooperation Programme and Challenges for Formal Education, Research and Donor Organisations H anoi, Vietnam : Sw ed ish International Develop m ent Agency Up hoff, N (ed ) (2002) Agroecological Innovations Lond on: Earthscan ... ecological know led ge system In N G Roă ling and M .A. E International Jou rnal of Agricu ltu ral Su stainability Wagem akers (ed s) Facilitating Sustainable Agriculture: Participatory Learning and Adaptive... in harmony with nature” , Igu acu Falls, Parana, Brazil, Au gu st 11–15, 2003 Ponta Grossa, Brazil: FEBRAPDP Shanks, E and Bu i T.D (2001) Field Based Learning and Training in Participatory Approaches... innovations it w ill be easier to engage negotiations abou t organisational innovations to rationalise forage resou rce m anagem ent at the village scale Ou r p articip atory sim u lation m ethod p roved

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