Mai Thj Lan Anh va Dtg Tap chi KHOA HOC & CONG NGHE 118(04): 191 - 196
DAC BIEM HOA SINH H p C CUA MOT SO YEU TO MOI T R U C X N G DAT LUA TAI Q U Y 6 T T H A N G , THANH PHO TIHAI NGUYEN
Mai Thi Lan Anh', Stephen Joseph^, Lukas Van Zwieten^, Hoang Trang Kien', Hoang Lam', Van Hiru Tap', Mai Van Trinh^
'Trucmg DH Khoa hgc - DH Thai Nguyin. 'DH New South Wales. NSW2052 Australia Vi^n Moi [rudng Nong nghiep (lAE). Ha Noi, Viel Nam TOMTAT
Nghien cuu nay trinh bay nhiJng anh huong ciia than sinh hoc den sy bien dgng ham lugng chat hiiu ca, N-NH4 trong dat va mot so yeu to moi truang dat Udng liia nhu pH, Eh trong dat ihit pha cat or khu vuc ngoai 6 ciia thanh pho Thai Nguyen, Viet Nam. Ket qua nghien cuu ciia nam thii nhat 6 thi nghiem nghien cuu 3 nam gom cac cong thiic thii nghiem voi than sinh hpc va phan chudng dugc danh gia trong bai bao nay. Than sinh hoc dugc san xuat nho qua trinh dot nhiet phan bang thiet bi TLUD-drum ciia hdn hgp sinh khdi gom trau, rom ra, Ue va go. Trudc khi nhiet phan, lat ca sinh khdi nay dugc Iron vai hdn hgp cd chiia thanh phan dinh duong cao. Sau 1 nam dau lien bon than sinh hpc, ham lugng chat hiiu co trong dat da tang len 62,5%. Than sinh hgc li voi phan chudng da phat huy dac ti'nh hap phu tot doi voi cac thanh phan khoang chat nhu sat va amoni, nho do vira giiip gm Iai chat dmh dudng Irong dat vira giam dgc sat trong dat liia,
Tir khoa: Cdc bon hiru ca trong ddt. ddt trdng IUa, than sinh hgc, phdn compost.
DAT VAN DE
Liia (Oryza sativa) la mgt loai cay luang thuc quan trpng va la nguon thuc pham Iau doi han bat ky cay tr6ng khac. Tuy nhien, viec trong va san xuat liia gao nay sinh mgt so van de moi truang nhu phat thai khi nha kinh, dac biet la khi metan (CH4) va nito oxit (NiO), van de quan ly so luong lon ram ra va nuoc tucri can thiet cho cac giai doan ngap nudc lien tuc (Bueno va Lafarge, 2009) [3].
Nhflng canh ddng lua thoat nudc t6t, hoac la do nguon nudc ban che hoac lam co sue khi de tang cuong goc de nhanh, la cac bien phap canh tac pho bien a cac nuoc san xuat liia gao ldn (IRRl, 2013) [5], He tbSng ihoat nudc lao ra viing ky khi dac trung trong dat noi xay ra dong thai hai qua trinh nitrat hda va khu nitrat (Smith va Patrick, 1983) [9]. Trong qua trinh nitrat hda, NH^'^cd sEn U-ong dat bi oxy hda thanh NO3", trong phan ung khii nitrat, NO3' bj khu thanh N2O, cuoi ciing thanh N2. Tuy nhien, do m^t phan moi trudng dat la ky khi nen mot sd luting dang ke N2O thoat vao khi quySn thong qua cac lo hong ciia dat. Khoang hong nay thudng cd d?c linh oxy hda (Smith
* Tel. 0I635IO2I32. Email-mailananh-festn@gmailcom
va Patrick, 1983) [9] Ngoai ra, su linh dpng sin cd C trong dat cung tang cudng qua trinh khu thdng qua viec cung cap chal cho dien lti de khir nitrat va ibiic day qua trinb yem khi.
Vi vay, nudc va cac chat hiiu co trong nhirng canh ddng liia la yeu to tac ddng den phat thai CH4 va N2O. Ngoai cac dieu kien dat, cay Iua ciing tang cudng phal thai CH4 va N2O bang each cung cap cac chat cho dien tir.
Viet Nam cd khoang 6 trieu ha dSt trdng liia Ilia, la mgt trong hai qudc gia san xuat liia gao va xual khau hang dau the gidi (FAOSTAT, 2013) [4]. Ci day, ap dung phan chudng (FYM) Cling vdi phan dam trong rupng lua la mgl thuc le phd bign (Dung el al., 2003) [2].
Tuy nhien ciing vdi qua trinh cdng nghiep hda nong nghiep nong thdn, cac thiet bi may city dugc su dung phd bien keo theo nguon phan chudng giam dang ke. De dam bao an ninh luang thuc, phan khoang la lua chgn sd mgl ciia ndng dan hien nay. He qua la cac canh ddng Ilia ngay ciuig cd nguy ca ngheo kiel dinh dudng, ham lugng cac chat hiru co giam, d|c biet la cac bon, Trong bdi canh do, than sinh hgc tir phe pham ndng nghiep la mot giai phap hiju hieu bd sung ngudn cac bon vao dat, cai tao cac dac tinh dinh dudng ciia dat.
Mai Thi Lan Anh vd Dtg Tap chi KHOA HOC & CONG NGHE 118(04): 191-196 nang cao nang xuat cay trdng (Joshep &
Lehmann, 2009). Trong khuon khd de tai
"Nghiin cuu dnh huffng cua cdc yiu to moi trudng din cdn bang cacbon trong dat lua nu&c hu&ng din gidm phdt thai khi nhd kinh (CH4, COi)", bai bao nay trinh bay nhii'ng ket qua ban dau ve dac diem hda sinh hgc cua dat trdng liia d xdm Trung Thanh, xa Quy8t Thang, Ihanh phd Thai Nguyen, so sanh vdl cac che dp canh lac thdng thudng ciia ndng dan hicn nay vdi ciing mgt che do canh tac nhu nhau klii bd sung than sinh hgc vao dat.
DOI TLTONG, PHU'ONG PHAP NGHIEN CUU Nghien CUTJ dugc lien hanh d xa Quyet Th^ng-TP Thai Nguyen, tinh Thai Nguyen (2^34,275' Kinh do B^c; 105''46,796' vT dp Ddng). Dat cd thanh phan ca gidi gdm 79,8%
cat, 11,3% limon va 8,9% set, thudc loai dat thit pha cat, dung trpng 1,34 gjcm'. Kcl qua ngbien ciin bJ bang I cho thay PHKCI (1:5) dat 4,43 d muc axit nhe. Ham luong cation trao ddi trong dat khu vuc nghien cuu la 12,3 cmol/kg d miic trung binli Ham lugng cac bon biiTi ca 0,96%, nita tdng sd la 0,11%, Phot pho tdng sd 0,017%; kali tdng sd 0,03%
a miic ngheo den rat ngheo
Thi ngbiem ddng rudng dugc Ihiel ke theo khoi hoan chinh ngau nhien gdm 5 cdng thiic vdl 3 lan lap, mdi d thi nghiem rdng 30m^
(5m X 6m), Liia gidng Khang Dan 18 dugc thii' nghiem vdi cac che dp bdn phan gdm, Tl:
ddi chiing (khdng bdn); T2; NPK (iOOkg N+90Kg P,O;+60 kg KjO/ha cho vu xuan, 80kg N+60Kg P2O5+6O kg KjO/ha cho vu
he); T3: NPK+ 1,5 tan than sinh hgc; T4:
NPK+ 10 tin compost tii phan trau; T5;
NPK+ 10 tan compost tii phan trau cd chiia 5% than sinh hgc. Thdi gian ti^n hanh thi nghiem vu xuan nam 2013, tdng thdi gian sinh tnrdng va phat trien cua Ma, tinh tu liic cSy den Iiic thu hoach la 105 ngay.
Dac tinh rua than sinh hoc
Xii ly sinh khoi trudc khi dot se tao ra san phSm than sinh hgc cd chat lugng dinh duong cao (Bang 2) Cac Ioai sinh khdi gom trSu, rom, tre va gd (tre va gd dugc ngam dudi ao dg tang ham lugng dinh duong (Mai Lan Anh va Joseph, 2012) [I], dugc phdi trdn vdi hdn hgp chiia 10%. dal set, 5%. vdi, 10% phan trau tu-cfi, 2%> tro (dot tir rom). Sau khi phai kho khdng khi, sinh khdi dugc dot nhiet phan d nhiet dp 400 - eOCC b5ng thiing TLUD- drum (DK-TRl) (Joseph va Mai Lan Anh, 2012) [6]. Hon hpp phdi Iron cd muc dich tang ham lugng dinh duang va kha nang hoal ddng hda hpc ciia than sinh hgc, Dat set chiia ham lugng khoang da lugng va vi lugng; voi se bd sung canxi va magie, phan trau giiip bd sung ham lugng nita, tro tu ram chiia kali lang ham lugng khoang kali cho than.
Than sinh hgc su dung trong thi nghiem ddng rudng cd nhieu dac tinh hda hgc tdt vi chiia cac thanh phan P, K, Ca, Mg Than sinh hgc cd tinh kiem, giiip cai thien tinh axit ciia dat, CEC tuong duang 13,6 cmol/kg. Dac biet ty le C/N la 106,3, d ty le nay se giiip than sinh hgc ben viing trong dat trong thdi gian dai.
BangL Ddc tinh cita ddt khu vuc nghien cuu tnrac thi nghiem
p H ( l : S ) CEC OC N P K H , 0 KCl (cmol/kg) Tons so (%) 6.27 4.43 12,3 0.96 0,11 0,02 0.03
Fe
0,22 P detieu
K trao doi (mg/kg) 22,2 22.2 Bang 2. Dac tinh Ihan sinli hoc sir di,mg Irong Ihi nghiem nghien ciru va xudn 2013 p H „ , „ C E C C N C/N P
(1:4) c m o l k g %
9.78 13.6 55,3 0,52 106,3 5,12 K
g/kg 25,87
Ca 13.8
Mg 3,9
Mai Thi Lan Anh vd Dtg Tap chi KHOA HQC & CONG NGHE 118(04): 191 - 196 Mau dat dugc lly 5 15n d 5 giai doan phat
trien liia, dd la de nhanh rg, lam ddng, tro, chin siia va chin. Eh va pH dugc do bSng thi6l bi do hien trudng (Model E-20J-C-9 Combination Electrode Operation Instruction) trudc khi lay mau dat. Mau ddt lay ve dugc bao quan trong tii lanh, phan tich ngay cac chi tieu Fe^* theo phuang phap Cadarindp va Ocnina; N-NHj dugc phan tich theo phuang phap KJeldahl.
KET QUA VA THAO LUAN
Tinh chat oxy hoa khu cua dat lua tai khu vyc nghien cihi
Dat cd dac tinh khii trong d cac giai doan liia de nhanh rg, lam ddng va trd bdng (rH dao ddng lir 5,66 - 7,93 (rH = 2pH +2 Eh/59, a 25''C), tuy nhien giua cac giai doan phat trien cua Ilia cd nhung bien ddng khac nhau do anh hudng cua che do quan ly nudc tai rudng.
l e O A T SIDAT 7 1 0 A T SSDAT 9aOAT
Hinh I, Biin dgng pH trong dat qua cdc giai dogn phdt tnin ciia liia
Hinh 2. Bien dpng Eh trong ddt qua cdc giai dogn phdt triin cua lua
Ket qua nghien ciiu trinh bay trong hinh 1 cho thay pH dat ciia khu vuc nghien ciiu il bien ddng so vdi dat trudc thi nghiem (trong dieu kien khdng ngap nudc), pH dal trudc thi nghiem cd xu hudng chung la giam nhe d giai doan phat trien ciia Ilia. The dxy hda khii (Eh) the hien rat rd dac tinh ctia dat Iiia. 6 thdi diem 40 ngay sau cay, dat liia van ngap nudc khoang 5±2 cm, do dd tao nen mdi trudng khu xung quanh re Itia, Eh dat dao ddng tir 215 - 323mV. Dieu kien nay rat tbuan lgi cho cac phan ling phan hiiy chat hiru ca yem khi, ket qua la tao ra khi me tan (CH4) (Kogel- knabner et al., 2010) [8]. Day cung la nguyen nhan chii yeu gay ra su pbat thai khi nha kinh tir hoal ddng canh lac lua nudc.
Dong thai ciia Fe^*^ trong dat Iiia Ham lugng Fe^* trong dat phan anb dac tinb oxy bda kbii cua dal, Tir ket qua binh 3, cho thay ham lugng sal (II) cd xu hudng giam dan qua cac giai doan phat trien ctia liia va cd mdi quan he vdi muc nudc tai rudng. O 3 giai doan dau, dat ngap nudc, quan sat thay ham lugng sal khu thap nhat tai cdng thiic bdn 1,5 tan than smh boc + NPK, nguyen nhan cd the la do F J da hap ph... vao cac khoang hdng tren be mat than sinh hoc, nai cd cac nhdm chiic nang hoat ddng nbu -OH, -COH, -COOH, lao cac hen kel hiru co klioang ben virng (Mai Lan Anh & Joseph, 2012) [1], Co che nay rai cd y nghia lam giam ngd ddc sat Irong dat Ilia dac biet d nhiing nai cd ham lugng Fe ldng sd cao.
Dong thai ciia chat hun ca trong dat Su bien ddi ve ham luang chat huu co trong dat (SOM) vu xuan nam 2013 tai khu vuc nghien ciiu dugc the hien thdng qua dd thi hinh 4. Cd su bien ddng dang ke ciia ham lugng chal hiiu ca trong dat sau 36 ngay sau cay. Tlic la sau khoang thdi gian nay, cac chat hihi CO dugc dua vao dal trudc khi cay liia dang bi phan hiiy yem khi trong dieu kien khii ciia dat ngap nudc. Ham lugng chat hihi ca ldn nhat d cdng thuc bdn phan compost cd chiia 5%j than sinh hgc. SOM irong dat ddi chirng tang len dang ke sau khi cay liia do ldn
Mai Thi Lan Anh vd Dtg Tap chl KHOA HOC & CONG NGHE 118(04): 191-196 du thuc vat tir vu trudc con de lai trong dat.
Khi chuan bi cay, dat dugc cay va biia ngau tao dieu kien cho qua trinh phan hiiy cac loai re Ilia va gdc cdn Iai tir nhimg vu tnidc. Sau 36 ngay sau cay ham lugng chat huu ca trong dat cao nhat tai d thi nghiem bdn 10 tan phan u cd chua 5%. than sinh hpc va NPK, sau dd SOM giam dan qua cac giai doan phat trien ciia Ilia. Khdng cd su khac biel y ngbia (p>0,05) ve bien ddng ctia SOM trong dat d cac cdng thiic TI - T4 (SOM dao ddng tir 2,6 - 3,2%i) trong 4 giai doan phal trien ciia Iiia trudc khi thu hoach (De nhanh rd, Iam ddng, trd boa va chin sira). Htong cdng thiic bdn 1,5 tan than sinh hgc + NPK va cdng thiic bdn 10 tan phan compost li tir phan trau (khdng chiia than sinh hgc), lugng chat hiiu ca trong dat dat gia tri \an nhat d giai doan Ida lam ddng (51 ngay sau cay). Dat bdn 10 tan phan chudng u cd chua 5% than sinh bgc + NPK cho ham lugng chat hiru co cao nhat. Sau vu dau tien, SOM lang trung binli 62,5%i d cac d thi nghiem cd bd sung chat bii'u ca. Vdi cdng thuc chi bdn NPK, ham lugng SOM giam xudng, mac dil sir khac biet cung chua cd y ngbia.
0 ^
_ 36 DAT S l D A f 7 1 DAT 88 DAT STN
Hinh 3. Bien dgng Fe^* linh dgng trong dat qua cdc giai doan phdt triin ciia lua, H * ddt ngap nuac 5-7 cm, SM. ddt ngdp mudc 2-3 cm, • . ddt
khong ngap nudc (DAT. Ngdy sau cdy)
BCtrol BNPK
^NPK-'l.BtBC BNPK+lOtCPnoBC BNPK-^lOtCP&SC
Hinh 4. Bien dong hdm lugng chdt hieu ca trong ddt Ida
Dong thai ciia N-NH'*'1inh d6ng trong dat
De nhinh r j Lamaerg Tr6 ChinsCra CWn
Hinh 5. Bien dgng hdm lugng N-NH** linh dong trong dal Ida
Ham Iugng ciia N-NH''*linh ddng trong dat co xu hudng giam dan theo cac giai doan sinh tnidng va phat trien ciia liia. Tuy nhien do su khac nhau ve thanh phan chat huu ca dau vao, khi ket thuc giai doan sinh trudng va phat trien ciia lua, dat cd bdn than sinh hgc van giii dugc luang dinh duong amoni dang ke. Ci cdng thiic ddi chiing, do khdng dugc bd sung them phan khoang hay phan htiu ca, nen sau qua trinh canh tac, lua da ISy di tu dit mol lugng dinh duang dang ke, tuang duong khoang 30 mg N-NH4/100g dSt (giam tir 35,9 - 10,6 mg/lOOg dit). Qua dd thi hinh 5 co
Mai Thi 1-an Anh vd Dig T^p chi KHOA HpC & CONG NGHE 118(04): 191-196 nhftng dau hieu cho thiy than sinh hgc cd th6
tucmg tac kha tdt vai dat trong viec giO lai cac thanh phan mang dien tich. Ham Iugng N- NH** dat cao nhit trong cdng thiic bdn 10 tan compost cd chiia 5% than sinh hgc + NPK va cd xu hudng giam dan qua cac giai doan phat trifin ciia liia (60,4 - 3,6 mg/lOOg dit). Cd thd than sinh hgc hoat ddng nhu tac nhan Iam gia tang kha nang trao ddi cation cua dat, ngoai ra mdt sd thanh phan khoang trong hon hgp tien xii ly sinh khdi trudc khi nhiet phan ciing cd the gdp phan tang CEC cua dat. Do dd, lugng dang ke cation amoni trong.dat dugc giii lai, tir dd giai phdng dan dan, cung cap chg cay trdng.
KET LUAN
Than stnh hpc cd y nghia quan trpng trong viec bd sung chSt hiiu co vao dat, do cd chiia ham lugng cac bon khoang 55,3%i. Sinh khdi rom, trau, tre, gd dugc trdn vdi hdn hgp dat set, vdi, trg va phan trau giiip tang ham lugng khoang chat va hoat tfnh sinh hda cho than sinh hgc ddng thdi tan dung dugc cac ngudn nguyen li§u tir nhien lam phan bdn. Than sinh hgc cd the bdn tru'c tiep vao dat hoac phdi Iron vdi phan chudng li 45-60 ngay cho hoai muc. Sa*; 1 nam dan t'en bdn th?n sinh hpc, ham lugng chat hiiu ca trong dat da tang ien 62,5%. Than sinh hpc li vdi phan chudng da phat huy dac tinh hap phu idi ddi vdi cac thanh phan khoang chat nhu sat va amoni, nhd dd vira giiip giiia Iai chat dinh dudng trong dat vira giam ddc sat trong dat liia. Sau tbdi gian thi nghiem, dat cd than sinh hgc cd ham lugng chat hun eg, N-NH4* cao ban so vdi cac cdng thiic khac. Trong cac giai doan phat trien ciia liia, than sinh hgc va phan huu eg dau vao cd vai trd quan trpng trong viec hip thu ion sat, tao cac lien kdt hihi ca khoang ben viing, giiip giam ddc tinh cua sat (II) ddi vdi rlliia.
TAI LIEU THAM KHAO [I]. Mai Lan Anh, T., & Joseph, S , (2012), "Banh gia chat lugng than sinh hoc san xuat tir mot so loai vSt lieu hiru ca pho bien d Mien Bac Viel Nam", Tgp chi Khoa hoc Cdng nghe DH Thdi Nguyen, 53, 3-7.
[2]. Dung, N. H., Thien, T. C, Hong, N. V., Loc, N. T., Minh, D. V., Thau, T. D., Son, T. T., (1999), "Impact of agro-chemical use on productivity and health in Vietnam", Economy and environment program for Southeast Asia (EEPSEA).
[3]. Bueno, C. S., & Lafarge, T., (2009), "Higher crop performance of nee hybrids than of elite inbreds in the tropics: 1. Hybnds accumulate more biomass during each phenological phase". Field Crops Research, 112, (2), 229-237.
[4]. FAOSTAT, (2013), "Land resources database". On line at http://faostat.org (Accessed December 2011)
[5]. Intemational Rice Research Inslimte (b).
Saving water: Alternate wetting and drying.online at: httpV/www.knQwledgebank.irri.orti [Accessed April 2013].
[6], Joseph, S., & Mai, L, A., (2012), "North Vietnam Villagers Develop Strategies to Help Combal Global Warming and Improve Household Health"; Results of First 18 months Of Village Biochar Program", http://www.biochar- intemational.org/''ites/defauIt/flles/Evaluation_of_
CARE__Vielnam Biochar_final.pdf
[7]. Joshep, S„ & Lehmann, J., (2009), "Biochar for Environmental Management Science And
Technology". Earthscan Publishers Ltd [8]. Kogel-knabner, I., Amelung, W , Cao, Z, Fiedler, S , Frenzel, P., Jahn, R., ... Schloter. M , (2010),"Biogeochemistry of paddy so\\s" Geoderma, 157,(1-2), 1-14
[9], Smith, C. J., & Patrick Jr, W. H., (1983),"Nitrous oxide emission as affected by alternate anaerobic and aerobic conditions from soil suspensions enriched with ammonium sulfate",5o/7 Biology and Biochemistry, 15, (6), 693-697,
Mai Thj Lan Anh vo £>/g Tap chi KHOA HOC & CONG N G H £ 118(04): 191 - 196
S U M M A R Y
P R O P E R T I E S O F E N V I R O N M E N T A L F A C T O R S I N P A D D Y R I C E S O I L I N Q U Y E T T H A N G , T H A I N G U Y E N C I T Y
Mai Thi Lan Anh'*, Stephen Joseph^; Lukas Van Zwieten^;
Hoang Trung Kien'; Hoang Lam', Van Huu Tap', Mai Van Trinh^
'College of Science - TNU: 'Ne^v South Wales University, NSW2052 Australia:
^Inslilule for Agricultural Environmenl
Rice on the upland areas of Viemam is mostly planted on the soils which are acidic and low organic matters. Biochar could increases pH and organic carbon contents in the soil as well as increasing yields if combined either with compost or with chemical fertilizer. This study investigates effects of biochar as well as biochar-composting on changes in soil organic matters (SOM) and some environmental factors such as pH, Eh, Fe'*, N-NH4 in a sandy clay loam, in suburb of Thai Nguyen City, Vietnam (2t°34,275' North; I05''46,796' East).- This paper reports on the results ofthe first of a three year field tnal. A composite high nutnenl biochar was produced by blending buffalo dung. Hybrid Acacia wood, bamboo, n e e husk, rice straw. All feedstocks were coated wilh a mixture of buffalo dung 5%, lime 2%; 10% clay, 5 % of rice straw ash to increase the mineral content on the biochar's surface. The mixture of minerals and biomass (rice straw and timber wood) were dried and then pyrolysis in TLUD - drum oven at 400-500"C to produce the biochar. After first year of expenments, the utilization of organic amendments increased the amount of SOM compared lo the control soil. Biochar incorporate wilh compost manure was stable in soil. In addiction, biochar absorbs ion in mineral-organic complex, reducing iron toxic in paddy field.
Key words. Soil organic carbon, rice, biochar, compost
Ngdy nhan bar 13/3/2014. Ngdy phdn biin- 15/3/2014; Ngdy duyel ddng: 25/3/2014 Phdn bien khoa hpc: TS. Ngd Vdn Gidi - Trudng DH Khoa hgc - DH Thdi Nguyen
Tel. 01635102132. Email- iiiailananhjesln@gmad a 196
