VERMICOMPOST AS AN ALTERNATIVE OF MANAGEMENT FOR WATER HYACINTH

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1 Rev. Int. Contm. Amie. 32 (4) , 2016 DOI: /RICA VERMICOMPOST AS AN ALTERNATIVE OF MANAGEMENT FOR WATER HYACINTH Dioselin ÁLVAREZ BERNAL 1 *, Mrcos Alfonso LASTIRI HERNÁNDEZ 1, Héctor René BUELNA OSBEN 1, Silvi Mriel CONTRERAS RAMOS 2 nd Miguel MORA 3 1 Centro Interdisciplinrio de Investigción pr el Desrrollo Integrl Regionl de Michocán, Instituto Politécnico Ncionl. Justo Sierr 28, Centro, Jiquilpn, Michocán, México, C.P Centro de Investigción y Asistenci en Tecnologí y Diseño del Estdo de Jlisco A.C. (CIATEJ). Avenid Normlists 800, Coloni Colins de l Norml, Gudljr, Jlisco, México, C.P Deprtment of Wildlife nd Fisheries Sciences, Texs A&M University, College Sttion , Texs, United Sttes * Autor pr correspondenci: dlvrez@ipn.mx (Received June 2015; ccepted Ferury 2016) Key words: Eiseni fetid, vermicomposting, Eichhorni crssipes, slinity, metls, orgnic fertilizer, electricl conductivity ABSTRACT Aqutic weeds, such s Eichhorni crssipes (Mrt.) Solms (wter hycinth) cn e used s rw mteril for vermicompost. Vermicompost is the product of microil decomposition of orgnic wste through the digestive trcts of erthworms. The im of this work ws to use wter hycinth to otin stle nd mture vermicompost. Three tretments were performed for vermicomposting, tretment one with 100 % of wter hycinth, tretment two with 100 % of cow mnure nd tretment three with 50 % of wter hycinth nd 50 % of cow mnure. The erthworm used ws Eiseni fetid Svigny. Vermicompost ws chrcterized physiclly, chemiclly nd microiologiclly, nd mesured y indexes of stility nd mturity, s well, metl concentrtions were detemined. Germintion index ws otined with four different seeds: rdish (Rphnus stivus L.), lettuce (Lctuc stiv L.), cucumer (Cucumis spp.) nd zucchini (Cucurit pepo L.). The three different tretments for vermicompost were stle nd mture fter 110 dys with 90 % of E. fetid survivl in ech tretment. The vermicompost with wter hycinth nd wter hycinth plus cow mnure hd high ph nd electricl conductivity. Rdish hd the est performnce in germintion index nd the three vermicompost were rich in metls. We conclude tht vermicomposting is suitle for mnging wter hycinth ecuse it cn produce stle, mture, nd rich in nutrients vermicompost, which is useful s orgnic fertilizer or soil improver. Plrs clve: Eiseni fetid, vermicompostje, Eichhorni crssipes, slinidd, metles, fertiliznte orgánico, conductividd eléctric RESUMEN Ls mlezs cuátics como Eichhorni crssipes (Mrt.) Solms (lirio cuático), pueden ser útiles en l elorción de vermicompost. El vermicompost es el producto de l

2 426 D. Álvrez Bernl et l. descomposición de desechos orgánicos por medio de los microorgnismos del trcto digestivo de ls lomrices. El ojetivo de este trjo fue utilizr el lirio cuático pr otener un vermicompost estle y mduro. Se relizron tres trtmientos: uno con el 100 % de lirio cuático, el dos con 100 % de estiércol y el tres con 50 % lirio cuático y 50 % de estiércol, l lomriz utilizd fue Eiseni fetid Svigny. Los vermicompost se crcterizron físic, químic y microiológicmente, demás se midieron índices de mdurez y estilidd, sí como l concentrción de metles. El índice de germinción se relizó con cutro semills diferentes: ráno (Rphnus stivus L.), lechug (Lctuc stiv L.), pepino (Cucumis spp.) y clcit (Cucurit pepo L.). Los tres trtmientos resultron ser estles y mduros después de 110 dís de vermicompostje con un índice de supervivenci de E. Fetid de 90 %, los vermicompost con lirio cuático y lirio cuático más estiércol tuvieron un ph y un conductividd eléctric ltos. El ráno mostró un uen desempeño en el índice de germinción, los tres vermicompost resultron ricos en metles. Se concluye que el vermicompostje es decudo pr el mnejo del lirio cuático, deido que se otiene un vermicompost estle, mduro y rico en nutrientes, que puede utilizrse como fertiliznte orgánico o mejordor de suelos. INTRODUCTION The wter hycinth (WH), Eichhorni crssipes, is n emergent plnt of the fmily Pontederice nd is considered n invsive plnt ecuse of its rpid popultion growth (Ptil 2012). It tolertes intervls of ph, etween 6-8, nd grows rpidly when nitrogen levels re round 21 mg/l, phosphorus of 62 mg/l, iron of 0.6 mg/l, nd t lest 5 mg/l of clcium (Coetzee et l. 2007, Ruíz-Tellez et l. 2008). The WH is found in odies of wter with high nutrient levels (Mlik 2007). This qutic weed hs cused economic nd environmentl losses in mny countries, ecuse of its rpid growth it cn ostruct the ccess to the pumps used for irrigtion, cusing wter resources depletion, nd the spreding of mosquitoes nd flies which re vectors of numer of diseses (Ding et l. 2001). There re severl wys to hndle nd control WH including mechnicl, iologicl, nd chemicl methods. However, it is lso used to produce vlule products, such s, iogs, compost nd vermicompost (Mlik 2007). Vermicomposting is iologicl method where worms such s Eiseni fetid, Eudrilus eugenie or Lumricus ruellus (Gjlkshmi et l. 2001, Gupt et l. 2007) re used for trnsforming orgnic wste into vermicompost. It hs een reported tht vermicompost is rich in nutrients nd contin enzymes nd hormones tht stimulte plnt growth nd help them resist pthogens (Gjlshkmi nd Asi 2004). However, vermicompost cn hve lrge mount of slts, high electricl conductivity due to the origin from the rw mteril used, which cn e serious thret for sensile crops (Edwrds nd Bohlen 1996). The importnce of using wter hycinth for vermicomposting is ecuse this method stops its prolifertion y eliminting its ility to reproduce (Mlik 2007). Stility nd mturity of vermicompost is importnt ecuse it indictes when it is redy to e used s orgnic fertilizer or soil conditioner. One crucil nlysis is the germintion index tht indictes indirectly if the vermicompost contins phytotoxic compounds or lrge mount of slts tht cn dmge plnts (Brren et l. 2014, Khn et l. 2014). The im of this work ws using wter hycinth to produce stle nd mture vermicompost with Clifornin red worm in order to give n lterntive mngement of this qutic weed. MATERIALS AND METHODS Smpling site WH ws collected from three drins in the irrigtion district 024, Ciéneg de Chpl, in northest Michocán, México (19º nd 20º N; 102º 43 16, 102º W), t n ltitude of 1525 msl (INEGI 2014). The drins in the irrigtion district hd the following flor: Hydrocotyle vulgris L., Scirpus spp., Pisti strtiotes L., Lemn minor L. Griff., Phrgmites ustrlis (Cv.) Trin. ex Steud., Typh domingensis Pers. nd E. crssipes, the ltter eing the most undnt species (PCIMALC 2005). Smples of WH were wshed with potle wter to remove sediment prticles ttched to the roots

3 VERMICOMPOST OF WATER HYACINTH 427 nd leves. The whole plnt ws cut in segments of 2 to 3 cm. Cttle mnure (CM) ws collected from cowshed in Jiquilpn, Michocán. The min physicl nd chemicl chrcteristics of WH nd CM re shown in Tle I. TABLE I. PHYSICAL AND CHEMICAL CHARACTERIS- TICS OF RAW MATERIALS FOR VERMICOM- POST Prmeter WH CM Moisture (%) 92 ± ± 1 Ash (%) 79 ± ± 1 ph 8.5 ± ± 0.2 Electricl conductivity (ds/ m) 2.7 ± ± 0.2 Totl orgnic cron (g/kg) 25.5 ± ± 11 Fulvic cid (g/kg) 7.8 ± ± 0.1 Humic cid (g/kg) 17.7 ± ± 0.3 Totl nitrogen (g/kg) 0.54 ± ± 2 WH: wter hycinth, CM: cow mnure WH nd CM were pre-treted y forming pile of 50 cm nd covering with drk plstic g (600 clier). The pile ws wtered nd turned every other dy, during 20 dys to eliminte voltile gses potentilly toxic to E. fetid erthworms. Experimentl design Three eds (1 m wide, 2 m long nd 0.3 m high) were plced for ech tretment, which were 1) WH, 2) CM nd 3) mixture of WH (50 %) nd CM (50 %) (WH+CM). Ech ed ws treted with 1.5 kg of dult Clifornin red worms (E. fetid), nd then ws covered with shdow mesh to prevent moisture loss nd irds eting the worms. The moisture content ws mintined nd djusted to 80 % on dily sis. For survivl index of erthworms, rndom smple ws tken using frmework of 0.5 m y 0.5 m ech side, plced in the middle of the ed to eliminte the edge effect, t 20 cm of depth of the ed. Survivl ws clculted s the rtio etween the numer of orgnisms collected t the end of the experiment nd the numer of initil orgnisms (Allen 1990). After 110 dys erthworms were seprted from eds with specific trps. A smple ws collected from ech ed nd then ir dried t room temperture in the shde, grounded nd stored in plstic g for lter nlysis. Physicl nd chemicl nlysis Ech smple ws nlyzed for the following prmeters: ph nd electricl conductivity (EC) using distilled wter in 1:10 (w/v), totl orgnic cron (Nelson nd Sommer 1982), totl Kjeldh nitrogen (Bremner nd Mulvney 1982), moisture (Alef nd Nnnipieri 1995), oxidle orgnic cron nd CO 2 (Sánchez-Monedero et l. 1996), inorgnic cron (Pge 1982), ction exchnge cpcity (Uehr nd Gillmn 1981), finlly, NH 4 + nd NO 3 - were mesured y colorimetric techniques (APHA 1988). Germintion index The germintion index ws mesured using seeds of R. stivus, Cucumis spp., L. stiv nd C. pepo, ccording to Zucconi et l. (1981). Microiologicl nlysis Escherichi coli, totl nd fecl coliforms were determined in vermicompost with USEPA method 1680 (2010), Slmonell spp. with method 1682 (USEPA 1998), nd helminth eggs s follows. The smples were mixed with uffered wter contining surfctnt 0.1% (Triton X-100). Afterwrds lrge prticles were llowed to precipitte nd the superntnt ws decnted. The sediment ws sujected to density grdient centrifugtion using mgnesium sulfte (specific grvity 1.2 g cm 3 ). Smll prticles were removed y second screening on smll mesh size screen (400 mesh US stndrd, 38 μm, stinless steel,) nd proteinceous mteril y n cid lcohol/ethyl ether extrction. The concentrte ws susequently incuted t 26 ºC for 10 dys nd microscopiclly exmined for helminth eggs on Sedgwick-Rfter counting chmer (Husser Scientific, Horshm, P.) (USEPA 2003, Appendix I). Metl nlysis A susmple of vermicompost ws used to determine metls content (C, Co, Cu, Fe, Mg, Mn, Mo, Se, Zn, Si, B, B). 0.3 g of vermicompost were plced in polytetrfluoroethylene, flme retrdnt (PTFE-TFM) tues nd were digested in microwve (Multiwve 3000 Perkin Elmer USA ) with 1.0 ml of concentrted hydrochloric cid (HCl), 9.0 ml of concentrted nitric cid (HNO 3 ) nd 2.0 ml of hydrogen peroxide t 30 % (H 2 O 2 ). The metls were quntified y opticl emission spectroscopy inductively coupled plsm (ICP-OES model Optim 4300 DV, PerkinElmer Instruments USA ). Sttisticl nlysis An nlysis of vrince ws conducted long with Tukey test to determine significnt differences etween tretments using the sttisticl pckge SAS 9.1 (2004). The significnce level ws set t P 0.05.

4 428 D. Álvrez Bernl et l. TABLE II. MATURITY AND STABILITY INDEXES FOR VERMICOM- POSTS OBTAINED WITH VERMICOMPOSTING PROCESS Prmeter WH CM WH+CM SMD Mturity nd stility index ph EC Bulk density (g/ ml) N-NH + 4 (mg/kg) < N-NO 2 (mg/kg) < 5 2 N-NO 3 (mg/kg) < NH 4 /NO < 3 3 HA/FA >1.9 5 FA (g/kg) CEXC (g/kg) TOC (g/kg) > CO 2 (mg/kg/dy) Bernl et l. (1998), 2 ASCP (2001), 3 TMECC (2010), 4 Hue nd Liu (1995), 5 Iglesis-Jiménez nd Pérez-Grcí (1992), 6 Lsridi et l. (2006) WH: wter hycinth, CM: cow mnure, WH+CM: wter hycinth plus cow mnure, SMD: Significnce miniml difference (p 0.05) HA/FA: humic cid-fulvic cid rtio, FA: fulvic cid, CEXC: ction exchnge cpcity, TOC: totl orgnic cron RESULTS AND DISCUSSION A stle nd mture vermicompost ws otined fter 110 dys nd their chemicl nd physicl properties re shown in Tle II. Gupt et l. (2007) reported 147 dys to otin stle nd mture vermicompost, while Gjlkshmi et l. (2001) reported six months. In our study, the shorter process time ws due to the lrge mount of erthworms dded to ech ed. In ech ed the survivl index ws 90 % ± 2, indicting tht the erthworms dpted to the mterils used nd tht the WH from dringes did not contin compounds tht interfered with their development. This is in contrst with Singh nd Klmdhd (2013) who found decrese in erthworm survivl, eing necessry to use mixture of 25 % WH nd 75 % cow dung. An increse in the percentge of WH in the mixture resulted in n increse in mortlity of these erthworms (Glkshmi et l. 2001, Gupt 2007, Zires et l. 2011). Pre-compost is necessry to void erthworm mortlity (Mupondi et l. 2011). The ph ws slightly sline in the three vermicomposts. CM nd WH hd ph of 8.5 nd 9.4 respectively, nd EC rnging from 3.3 to 4.01 ds/m, indicting importnt presence of slts which my hve little impct on slt tolernt crops (Tle II). These results of EC were similr to those reported y Crdoso nd Rmírez (2001) with n EC of 4 mmhos/cm nd ph vlue of 7.2. Vermicompost produced with WH nd iosolids is lkline ecuse the clciferous glnds dd clcium (Bollo 1999). However, Gupt et l. (2007) otined ph vlue of 7 fter 147 dys with vermicompost of ovine mnure nd WH. WH hs een considered nturl kidney for distured wters. It hs een used s iofilter of wstewter rich in orgnic nd inorgnic nutrients, s well s wter contminted with toxic metls nd persistent orgnic compounds (Mlik 2007). WH lso tkes slts from dringe wter (Zhou et l. 2007, Singh nd Klmdhd 2013). Wters from the dringe system of Ciéneg de Chpl re rckish (Silv-Grcí et l. 2006), nd CM hs lrge mount of slts s well (EC 5.5 ds/m), which explins the high vlues of ph nd EC found in the vermicompost in this study. The orgnic mtter content nd ction exchnge cpcity of the three vermicomposts were high (Tle II), indicting tht they re rich in nutrients nd therefore suitle s orgnic mendment. It is known tht vermicomposting of solid wste results in nutrient rich humus, produced y microorgnisms in the digestive system of erthworms (Gjlshkmi nd Asi 2004). Vermicompost stility is relted with the decomposition of orgnic mtter (Bustmnte et l. 2008), mesured y minerliztion of cron nd nitrogen (CO 2 nd NH 4 + ). The vlues of CO 2 nd NH 4 + otined indicted stility despite significnt differences etween tretments (Tle II). The mturity indictes tht vermicompost cn e used

5 VERMICOMPOST OF WATER HYACINTH Germintion index (%) c c c 24 h 48 h 72 h 96 h 120 h 20 c c 0 CM Rdish ccc cc cc Lettuce Cucumer Zucchini WH Rdish Lettuce Cucumer Zucchini WH+CM Rdish ccc cc Lettuce Cucumer cc Zucchini Fig. 1. Germintion index of different seeds with extrcts of vermicompost CM: cow mnure, WH: wter hycinth, WH+CM: wter hycinth plus cow mnure. Brs with the sme letter men there re no significnt differences (p 0.05) s orgnic fertilizer to e microiologiclly stle. The prmeters tht indicte mturity in compost re oxidizle orgnic cron, C:N rtio nd germintion index (Sánchez-Monedero et l. 2001). For the oxidizle orgnic cron nd C:N rtio, there were significnt differences etween smples (Tle II), these results indicte stility nd mturity in the three tretments. Germintion index (GI) is one of the most importnt prmeters for stility. The sensitivity of seeds to the phytotoxic compounds nd slts ws vried nd the est response ws the rdish with germintion t 24 h. In contrst, the other seeds hd n dpttion phse nd there ws no germintion in the first 48 h until the 72 h were reched. Vermicompost WH+CM, hd lower rtes of germintion for ll seeds, due to its high conductivity (Fig. 1). Zires et l. (2011) suspects tht the phytotoxic compounds from WH re responsile for the low percentge in germintion index. The lettuce seeds re more sensitive to slts nd phytotoxic compounds. In ll the vermicompost the germintion of these seeds ws recorded until 96 h. Germintion in vermicompost WH ws 70 %, in WH+CM ws 80 % fter 120 h, nd 100 % in CM. The ove indictes tht despite hving different degrees of mturity, nd no phytotoxic compounds, slts ffect germintion stge. Vermicompost with WH hd low rte of GI with seeds of cucumer nd lettuce compred with seeds of rdish (Fig. 1). These results coincide with those from Zires et l. (2011), who found low percentge of GI with vermicompost of WH. In contrst, zucchini seeds hve one hundred % of GI despite the high EC of the WH vermicompost. Mixed vermicompost WH+CM hd lower GI in most seeds compred with other tretments, likely ecuse of the slt excess, nd EC of 4.01 ds/m. Ptidr et l. (2013) found 60 % of GI for rdish with mixed vermicompost (WH + CM). Metl concentrtions in three vermicompost re shown in Tle III. There were no significnt differences mong tretments, nd most of the metls were in gret concentrtions (i.e. C mg/kg), except for B, B, Se nd Mo. There is evidence tht metls ccumulte in WH. Singh nd Klmdhd (2013) found similr concentrtions of Zn, Mn, Cu nd Fe fter 45 dys of vermicomposting. Nevertheless, high ph reduce iovliility of these metls (Ingelmo et l. 2012). The concentrtions of Co nd Cu in the three tretments were elow the upper limits reported y the Europen Comission (2014) nd WRAP (2014). Zinc ws found within the upper limits of US Composting Council (TMECC 2010), ut ws higher for Europen Comission nd WRAP. It is importnt to

6 430 D. Álvrez Bernl et l. TABLE III. METALS IN VERMICOMPOST Metl CM (mg/kg) WH (mg/kg) WH+CM (mg/kg) SMD Upper limit C Co Cu Fe Mg Mn Mo Se Zn c Si B B Source: Europen Commission (2014), Source: WRAP (2014), c Source: US Composting Council (TMECC 2010). SMD: Significnce miniml difference (P 0.05), CM: cow mnure, WH: wter hycinth, WH+CM: wter hycinth plus cow mnure evlute metls in compost ecuse of the risks to the environment when using orgnic mendments with high concentrtion of metls. Regultions out metls in compost exist in mny countries except in México (Brren et l. 2014, Mohee nd Soohny 2014). The microil qulity of vermicompost is importnt ecuse pthogens cn cuse dmge to the helth of those who hndle this type of fertilizer. Microiologicl results re shown in Tle IV. Totl nd fecl coliforms nd helminth eggs were present in low vlues in three vermicomposts ( he/g). However, there re no regultions out the microil content in compost. Results for E. coli were low in three vermicomposts nd Slmonell ws sent only in WH vermicompost ccording to the USEPA, Europen Commision, nd WRAP regultions. Hit nd Tre (2011) found higher mounts of totl nd fecl coliforms, Slmonell nd helminth eggs in vermicompost of sludge, in contrst with our low vlues. Interestingly, the British specifiction of qulity compost for growth medi requires the sence of such orgnisms (WRAP 2014). Cre must e tken with hndling vermicompost ecuse it is not completely sfe nd cn cuse stomch diseses in susceptile individuls. Therefore, it is importnt to use proper mngement techniques with pproprite personl equipment. CONCLUSION Wter odies with WH prolems cn e mnged y using the WH for vermicomposting, ecuse it cn produce stle, mture nd rich in nutrients vermicompost useful s orgnic fertilizer or soil improver. Besides, the whole process is crried out in reltively short time: 110 dys, including 20 dys pre-composting nd 90 dys of vermicomposting. Vermicompost of WH hs n importnt mount of metls nd slts, however some seeds cn thrive. ACKNOWLEDGMENTS We thnk Blnc E. Mnzo Cázres nd M. Isel Monres Escler for their technicl support. Lemon rnch (Secretrí de Desrrollo Rurl-Michocán) for providing the erthworms E. fetid nd to Secretrí de Investigción y Posgrdo del Instituto Politécnico Ncionl for funding (SIP ). TABLE IV. MICROBIAL PARAMETERS OF VERMICOMPOSTS Microorgnisms Vermicompost CM WH WH+CM Upper limit Escherichi coli (CFU/g) < 1000 c Slmonell spp. (CFU/25g) Asent < c Totl coliforms (CFU/g) Fecl coliforms (CFU/g) < c Helminth eggs (he/g) < c Source: Europen Commission (2014), Source: WRAP (2014), c Source: US Composting Council (TMECC 2010). Rows with the sme letter men there re not significnt differences (P 0.05). CFU: colony forming units, he: numer of helminths eggs, CM: cow mnure, WH: wter hycinth, WH+CM: wter hycinth plus cow mnure

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