KHOA HOC CONG NGHE
IMGHIEIM CLTLI SLT DLJIMG T H U E V A T D E P H U C H O I O A T S A U K H A I T H A C QUAIMEi S A T T A I T H A I IMGUYEIM
Qudch Ho^ng Long' T6MTAT
Nliani dira ra giai phap phuc hoi do phi dat sau khai khoang, mot thi ngbiem voi 4 lo^ cay phii dat la: Don buot. ngai dai, mSn trau va ducmg xi da dugc Uen hanb tir 7/2017 den 7/2019 tren dat vua hoan tho tai mo sat Trai Cau, Thai Nguyen. K&t qua cho thay ca 4 cay deu co kha nang sinh truong va phat tnen tot, cho khoi lupng than la cao n^n cbe phii dat t6t va co kha nang but thu kim loai nang trong dat tot. Ca 4 loai cay d6u CO kha nang phuc hoi do phi dait tot sau 2 nam trong. Danh gia mo hinh cay keo tai tuong cho thay tren dat sau khai khoang cay c6 tinh thich ung rong va kha nang sinh tnrong nhanh. nen ngoai kha nang cbe phu dat doc nhanh con cho sinh khoi lon tren dan vi dien Uch. Cay keo tai tuong duoc trong sau 2, 5 va 8 nAm da CO tac dung rat tich cue dfe phuc hoi do phi dat 6 ca 2 tang 6at ciia viing khai thac quang sat Trai Cau. D.iv la huong phuc hoi dat sau khai thac quang sat hieu qua va ben vung.
Til Wida: Dat sau khai khoang, cay phii da't, cay keo tai tupng. do phi dat. kim loai nAng.
I.MffflAU
Khi khai thac quang sat cung nhu cac loai quang khac, van de cai tao phuc hoi moi truang sau khai thac va dam bao chat lugng moi truong xung quanh trong qua trinh khai thac la yeu c3u cap bach hien nay. Cho den nay co kha nhi^u giai phap de phuc h6i dat sau khai khoang nhu: bi^n phap cong trinh, bien phap hoa hgc...nhung bien phap sinh hpc van co hieu qua kinh te nh^t vi dau tu chi phi thap va than thien vai moi truong.
Vl vay phuong phap su dung thuc vat vira xii Iy dugc 6 nhi^ni kim loai nang, vira phuc hoi dugc dp phi dat sau khai thac khoang san la npi dung nghien cuu de tim ra giai phap co hieu qua hien nay.
Z. NQI DUNG VA PHUDNG PHAP IVGHBV CUU 2.1. N6i dung nghi&n cihi
- Danh gia kha nSng phuc h6i diit va xu Iy dat bi 6 nhi^m ciia mgt so loai cay phu dat a viing mo sat Trai Cau.
- Danh gia kha nang phuc hoi dp phi dat ciia cay keo tai tuong tren dat sau khai thac mo sdt Trai Cau.
2.2. Ihiii gian v^ dia di^m nghien cmi - Thi nghiem cua npi dung 01 duoc thuc hien tir ngay 10/7/2017 den 10/7/2019; mo hinh thuc nghiem cua noi dung 02 duoc danh gia vao thang 7/2019.
- Dia diem- Viing mo sat Trai Cau. huy^n Dong Hy, Thai Xguyen.
2.3. Phuong ph&p nghien cihi 2.3.1. Phuong phap cho ngi dung 1
Nghien cuu tuy^n chon cac loai cay phii d^t cai tao dat sau khai khoang g6m 5 cong thuc thi nghidm, De CO tu nhien mpc, cay don buot, ngai dai. man tr4u, duong Xi 12].
- Thi nghiem dugc b6 tri tr^n dat da hoan tho vao thang 7 nam 2017, gom 5 cong thiic, nhac lai 3 Ian theo khoi ngau nhi^n hoan toan.
- Bien phap ky thuat: Trong mat do 16 khom/m- vm khoang each 25 x 25 cm. Phan bon NPK Van Dien 10:7:3 voi luong 1.000 kg/ha.
- Chi tieu theo doi: Nang suat sinh vat hpc (than, canh, la); phan tich dat truoc thi nghidm va sau 2 nam trong: Dung trgng, ty trpng, do xop, thanh phan cagioi; chi tieu hoa hoc dat: pH, mun (%), N tdng so (%), P2O5 tong so (%), KgO tong so (%); kim loai nang Fe, Zn, As, Pb, Cd.
- Sd lieu phan tich dat: Theo quy chuan QCVN 0:^MT:2015/BTNMT (BpTai nguydn va Moi truang, 2015) [1]: Chat lugng dat dimg cho san xuat nong nghiep (mg/kg dat kho): Pb < 70, Cd < 1,5, As <
15.
2.3.2. Phuong phap cho noi dung 2 Danh gia kha nang phuc hoi do phi dat ciia cay keo tai tugng tren dat sau khai thac mo sat. Nghien CLTU den hanh tren 3 loai mo hinh:
' NCS Trucmg D;H hoc Nong Uini - Dai hoc Thai Nguyen
NONG NGHIEP VA PHAT TRIEN NONG THON - KY 1 - THANG 11/2019 57
KHOA HOC COIW N G H t + Mo hinh 1: Keo tai tinmg sau trong 2 nam.
+ Mu hmh 2: Keo tai tugng sau trong 5 nam.
+ Mo hinh 3: Keo tai tucmg sau tr6ng 8 nam.
- Chi tieu nghien cuu: Cung giong nhu vai noi dung 1.
3. KET QUA NGHBU CUU VA THAO LUJW
3.1. Dinh gii kha ning phiic h6i dit vi xu ly d&
bi 6 nhi^m cua mOt s6 loai ciy phii d ^ o vimg mo sit Tr^iCau
3.1.1. Kha nang smh trudng, phat trien va phuc hoi dat cua cac loai cay trdng
Muc tieu phuc hoi dat sau khai khoang cho san xuat nong nghiep la dua dp phi dat v^ nhu h; nhien truac khi khai thac mo. Vi vay, doi vai bien phap sinh hgc thi cdn tim loai cay c6 kha ning sinh truong, phat tri^n nhanh, de lai sinh khoi lan va co kha nang htit thu kim loai nang trong dat.
a. Nang suat chat xanh cua cay thi nghiem So Ii6u theo doi ning suit chat xanh (than, canh, la) cua 4 cay tham gia thi nghiem (Bang 1) cho thiy:
Ca 4 loai cay trong d4u cho kha nang sinh truang va phat tri^n tdt tren dat vira hoan thd. Sau trdng 1 nam mat dat da dugc phii kin boi than la cay.
Nang suat sinh vat hpc (than, canh, la) sau 2 nam deu cao ban chac chin so cong thirc de co ta nhien mpc. Trong dd, cay don budt va min trau dat nang suit cao hon ca. Nhu vay cd the thay ca 4 cay thi nghiem d^u cd sinh khdi ldn va kha nang che phii dat tdt, dat tieu chi cai tao phuc hoi dat sau khai thac khoang san.
Bing 1. Ning suit thin cinh Ii ciia ciy trong ti^n dit sau khai khoing
DVT: g/khom
Cong thirc
1 2 2 4 5
Loaicay
Cotu nhien Don buot
Ngai dai Man trau Dirong xi LSD,,,,,
CVff)
Khcli lugng tuoi Sau 1
nam 55,81 120.55 108.32 113,64 99,69 7.85 4.19
Sau 2 nam 132.09 221.85 203,44 209,11 192,62 12,99 3,60
Khoi lugfng Idio Sau 1
nam 13,95 31.14 28.97 28.44 27,52 2,67 5,46
Sau 2 nam 35,66 60,68 55,43 57.78 53.53 5,82 5,87
b. Kha nSng but thu kun I091 n$iig cua ciy "^' ngiiifm
Kha ning htit thu kim lo^i niiiK trong tl^l cua cic ciy tham gia thi nghiem dugc trinh bay t^i b^S 2. Sd lieu phan dch ham lugng kim loai nan^ trong cay (than, canh, la) cho thay:
Bang 2. K^t qui phin tich him lugng kim W ° ^ trong ciy sau 2 nim trAng Cling
thuc I 2 ' 2
4 5
Loaicay Co tu nhien Don buot
Ngai dai Man trau IXrong XI LSD,,,,
CVff)
Ham luong trong cay (mg/kg) .'Vs 1 I'b Cd 5.12 1 17.77 0.124 i;,7fi 20.13 ' _a25l)_
7,14 1 19,78 _0454_
_S.ll 4 21,23 (i.ay _ S.22 i 2«,tll , (U'lli H.56 1 /,.'« ^ ui>;i__
4.19] 477] US (Ngudn: Phan tich t^ Vifn Klioa hoc Su sdng, Dai hQC Thai Nguyen)
Tat ca 4 loai ciy thi nghidm d^u cho kha nSng thu hut As, Pb va Cd kha va cao ban chac chan so vdi cong thuc CO mgc tu nhi^n. Nhu vay cd the thay ca 4 cay thi nghidm d^u cd kha nang hiil thu kim loai nang ti-ong dat tdt. dat ti^u chi cai tao phuc hoi dat sau khai thic khoing san.
3.1.2. Kha nang phuc h6i dat va xir ly dat bi 6 nhiim cua mqt so loai cay thi nghifm
a. Kha nang phuc hdi dd phi dat cua cay thi nghiem
Tr^n CO sd" tieu chi chgn loai cay ngin ngay nhung CO kha nang phuc hdi do phi dat nhanh. thi nghiem 4 loai cay da cho thay kha nang dd
- Sd lieu phan tich mpt sd linh chat hda hoc dat trudc thi nghiem va sau 2 nam thi ngbiem dugc tdng hgp d bang 3 cho thay sau 2 nam b-ong cac chi tieu hda tinh dat d^u thay ddi theo cbieu hudng tdt len Ham luang miin, dam, Ian, kali tdng so d^u cao ban chac chan so vdi cdng thiic de cd moc tu nhien va dat tnroc thi nghiem.
Nhu vay. cac cay phii dat b-ong thi nghiem , 1 2 nam da cd tie dung tich cue de phuc hdi m- . unh chit hda hgc dat a ting 0 - 20 cm cua vun;. , thac quang sit Trai Cau.
58 N O N G NGHIEP VA PHAT TRIEN N O N G THON - K , - THANG '/2019
KHOA HOC CONG NGHE
Cong thuc
1 2 2 4 5
Bang 3. Mot so ttnh chA h6a hpc lj)ai cay
Co tu nhien Hon buot
Ngai dai Mill! trau Duong XI Rat truoc thi nghiem
LSD„
CV(%)
PHKCI 5,40
d ^ 6 thi nghidm cay trong Mun
TO 1,54 5,51 1,89 5.62 ' 1.92 5.52 1,79 5.48 ; 1,75 5,36 1,49 0,31
3,06
0.21 6.68
N 0,09 0.13 0,13 0,11 0,11 0,08 a 01 3.77
sau2ncUn P.O,
(%)
o,o,s 0,11 0,11 0,09 0,09 0.07 0.01 8,91
K,() TO 0.15 0,19 0,18 0,16 0,17 0,14 0.02 7.42 (Nguon: Phan tich tai Vifn Khoa hoc Su song. Dai hoc Thai Nguyen)
- Sd lieu phan Uch mdt so tinh chat Iy hgc dit truoc thi nghidm va sau 2 nam thi nghiem dugc tdng hgp d' bang 4 cho thiy:
Sau 2 nSm trdng cay cac chi tieu ly tinh dat deu thay ddi theo chieu huong tdt len. Do xop dat d cac
cong thuc trong bdn cay d^u cao ban chic chan sau 2 nam trdng so vdi cdng thirc de cd bj nhien mgc vi dat trudc thi nghiem.
Cong thiic
1 2 2 4 5
Loai cay Co tu nhien
Don buot Ngai dai Man triiu Dirong xi Dat tnroc Iln nglu^m
LSI),.,,.
CV(t)
Dung trpng fe/cm') 1.26 1.22 1.22 1.21 1.21 1.29 0.06 2.48
Ty trpng fe/cm') 2.55 2.55 2.55 2.55 2.55 2.56
Do xop TO 50,6 52,2 52,2 52,6 52,6 49,6 2,16 2.30
Thanh p h ^ CO gioi (%) Cat
(>0,02 mm) 31 33 33 32 31 30
Limon (0,002-0.02 mm)
42 43 42 43 44 40
Set (<0.002 mm)
29 24 25 25 25 30
(Ngudn: Phong phan tich, Bd mon Khoa hoc Dat, DHNL Thai Nguyfn)
Nhuvay, cac cay phu dat trong thi nghiem sau 2 b. Kha nang xu ly dat bi d nhiim cua mgt so lo^i nam da cd tie dung tich cue de phuc hdi mot so tinh cay thi ngbifni
chit ly hgc dat d tang 0 - 2 0 cm ciia viing khai thac quang s<it Trai Cau.
Bing 5. Kim logi ning trong dat d thi nghidm ciy trdng sau 2 nam Cong thirc Loai cay
Diit truoc thi nghiem 1
2 2 4 5
Co tu nhit;n Don buot
Ngai dai Man Uau Duong xi 0C^'^• 03-MT:2015/BTNMT
LSD,.,,, CV(%)
Ham luong ldm loai nang (mg/kg) As
19.76 16.87 15.02 15.11 14.02 15.02 15 0,84 2,89
Pb 71,65 68,69 66,27 67,24 66,01 56,23 70 2,61 2,17
Cd 0,773 0,736 0,662 0,687 0,635 0.702 1.5 0,03 2.28
Zn 201,21 198,22 190,00 181„51 180,02 183,25
Fe ,531,43 500,02 482,03 480,61 477,37 481,82 200 1 5.06 1,47
23.82 2.66 _ (\guon Phan Uch lai Vien Klioa hoc Strsdng. Dai hoc Thai Xguyen)
NONG NGHIEP VA PHATTRIEN NONG THON - KY 1 - THANG 11/2019 59
KHOAHOC C6NO NGHt Dc danh gia kha nang xir ly 6 nhidm ciia kmi loai
nang ti-ong dat sau khai khoang, can tien hinh phin tich dat thl ngbiem trudc va sau trdng ciy 2 nam [3].
Sd lieu phin tich thu duoc d bang 5 cho thay 4 loai ciy trdng sau 2 nam da hut thu tich cue va ham lugng cic kim loai nang trong dat da giam chic chin so vdi dat trudc thi nghiem va dat miic quy chuan cho phep ciia QCVN 03-MT:2015/BTNMT cho dat
kha sinb hgc thl can dinh gia cay keo tai tugng xeni co nang sinh tiudng, phit tiien nhanh. tao nen : khdi Ion hay khdng nham phuc hdi do phi AaX duV*-"
nhanh chong |4j.
So heu theo doi nang suit chat xanh (than, canh.
Ia) ctia keo tai brpng d 3 md hinh co Uioi cay '2 n4ni, J nam va 8 nam (Bang 6) cho thay:
Cay keo tai tugng cd tinh thich iniir ront: :ikha ndng nghiep (tiir hai cay don budt vi ngai dai d chi " ^ ^ ^'"^ tirrdng nhanh. nen ngoai kha nang che tieu As).
Nhu vay. ca 4 loai cay sau 2 nim trdng deu cd kha ning xir ly tdt 6 nhidm kim loai nang trong dat sau khai khoang.
3.2. Dinh gii kha ning phyc h6i dO phi dat ciia ciy keo tai tugng h-fen dit sau khai thic mo sit Trgi Cau
3.2.1. Kha nAng sinh tnrdng. phat tnen ciia cay keo tai tuong
Muc tieu phuc hdi dat sau khai khoing cho sin xuat nong nghiep la dua dp phi dat vd nhu tu nhien
phii dat doc nhanh cdn cho sinh khdi Idn tren don vi dien tich. Nang suat chit xanh (than, canh. la) sau 2 nam trdng da dat 27,1 kg/cay tuoi. tuong duong 67.65 tan bioi/ha; khdi lugng khd 13.2 kj,'Aay. tuong duong 33,00 tan/ha. Sau 5 nam nang sual dian, canh, la dat cao d cii dang tuoi va kho, tinmg duong 232,00 tan/ha va 110,75 tan/ha. Sau 8 nam in'ing keo tai tuung d i cho sinh khoi rit Idn, tuong duong 358,75 tan tuai/ha va 183,50 tan kho/ha.
Nhu vay, ca 3 mo hinh cay keo tai tugng deu cd sinh khdi lon va kha nang che phu dat tot, dat tieu chl cai tao phuc hoi dit sau khai thac khoang san.
tnrdc khi khai thac md. Vi vay, ddi voi bien phap sinh
Bing 6. Sinh trudng vi ning suit thin cinh li cua keo tai tirgng b cic mO hinh trdng TT
1 2 3
Tudi cay
2 nam 5 nam 8 nam
DKthan (cm)
6,45 11,7 16,4
Chieu cao cay
(m) 6,3 11,5 17,6
Khoi lupng tiroi (kg/cay)
27,1 92,8 143,5
Khdi lupng khd (kg/cay)
13,2 44,3 73,4
Nang suat tuoi (tan/ha)
67.65 232.00 358.75
Nang suat khd (tan/ha)
33.00 110,75 183,50 3.2.2. Khd nUng phuc hdi dd phi dat ciia cay keo
tai tuong
Tieu chi chon cay cd kha nang phuc hdi dd phi diit nhanh d 3 md hinh keo tai lugng dugc trinh bay dudi day.
a. Kha nang cai tao tinh chat hda hoc dat ciia md hinh tiling cay keo tai tuong
Bing 7. Mot sd tinh chit hda hgc dat d cic md hinh trdng keo tai tugng _ _ _ Sd lieu phan tich mgt sd tinb chat hda hoc dat d cic mo hinh thu nghiem trdng keo tai tuong duac tdng hop b bang 7 cho thay sau 2 den 5 va 8 nam ti-dng keo cac chi tieu hda tinh dil d ca 2 tang dat 0 - 20 cm va 20 - 40 cm deu thay ddi theo chidu huang tdt Idn.
T T Tudi cay 2 nam
T;uig dat
(cm) PHKC Miin
(%)
20 - 4(1 0 - 2 0 2 ( ) ^ ) _
U - 20 20 - 40
3.08 2,75 (\giidn:Phan tich tai Vif n Khoa hoc Su sdng. Dai hoc Thai Nguyen)
NONG NGHIEP VA PHAT TRIEN NONG THON-Kr^ -THANG i 1/2019
KHOA HOC CdNG N G H £
Nhu viy. cay keo tai tugng dugc trdng sau 2, 5 va 8 nim da co tic dung rit tich cue de phtic hdi mgt sd tinh chat hda hoc dat a ca 2 tang dit cua vimg khai thac quang sit Trai Cau.
b. Kha nAng cai tao tmh chat ly hgc dat cua md hinh tidng cay keo tai tugng
Sd lidu phan tich mdt sd tinh chat Iy hpc dit d cic md hinh thii nghiem trdng keo tai higng dugc Bing 8. Mpt s6 tfnh chit ly hpc dit
tong hop d bing 8 cho thay sau 2 ddn 5 \ a S nim trong keo cic chi hdu ly tinh dat d ca 2 ting dit 0 - 20 cm vi 20 - 40 cm deu thay ddi theo chidu hudng tdt ldn.
Nhu viy, ciy keo tai tugng sau 2, 5 va 8 nam trdng da cd tac dung rit tich cue cho phuc hdi mdt sd tinh chit Iy hpc dit d ca 2 tang dit ciia vimg khai thic quang sit Trai Cau.
o c i c m d h i n h t r d n g k e o tai tugng TT Tudicay Ting dat
(cm) Dung trpng Cg/cm^
Ty trong (g/cm')
Dp xdp
(*)
Thanh phan eg gidi (%) Cat
(>0,02 mm) Limon (0.002-0.02
mm) Set (<0.002
mm)
1,28 40 29
1.23
49.8 51,8
39 31
8 nam 1.16 54.2
40 45
20-40 1.17 2,53 53,8 42 43 15 (Ngudn: Phong phan tich, Bd mdn Khoa hoc Dai, DHNL Thai. Vj?r/i en)
c. Kha ndng xu ly dat bi d nhiim ciia md hinh ^ang 9 cho thay sau 5 nam cay keo da hut thu Pb va tiong cay keo tai tuong ^^" ^ "^"^ ^^ ^ ^^ ^^™ lirpiig cic kim loai ning dd , , - , , trong dat d ca 2 tang dat mire quy chuan cho phep Dd danh gia kha nang xu Iy d nhiem cua kim loai . ,^r-,^- ^ »«-r om c /DTTHH*'?' U .*-'.
. ^ ' . cua ( K \ ^ 03-MT;2015/BTNMT cho dat nong nang trong dat sau khai khoing, da tidn hanh phan , ,.
tich dat ciia 3 md hinh trdng keo tai tuong sau 2 nim, 5 nam va 8 nam ti-dng. Sd lieu phin tich thu duoc d
Bang 9. Kim logi njing trong djtdf cic mdhinh trdng keo tai tugng IT
1 2 3
Tudi cay 2 nam
5 nam 8 nam QCVN 03-MT:2015/BTNMT
Tang dat (cm) 0-20 20-40
0-20 20-40
0-20 20-40
Ham luong kim loai nang (mg/kg) As
20,36 20,22 17,02 17,18 14,27 14,19 15
Pb 71,03 71,01 66,23 62,15 56,32 57,81 70
Cd 0.753 0.752 0.702 0.700 0.654 0.621 1.5
Zn 183,21 185,74 182,25 184.34 178.10 177,27 200
Fe 541,13 542,06 481,82 482,54 451,93 442,34 (Ngudn: Phan tich tai Vifn Khoa hgc Susdng, Dai
Mot uu diem ndi bat niia cua keo tai tuong la ciy than gd nen san pham gd duoc sii dung khong lam d nhidm va mdi dirdng.
4. KETLUAN
Ca 4 loai ciy cay phii dat: Don budt, Ngai dai, Min ti-iu va Duong xi deu cho kha nang sinh tnrdng va phat tiien tdt. cho khdi luong than la cao nen che phii dat tdt va cd kha nang hiit thu kim loai nang
hgc Ihai Nguyen)
trong dat tdt Ca 4 loai cay d4u cd kha nang phuc hdi do phi dat tdt sau 2 nam trdng.
Ciy keo tai tugng cd tinh thich img rdng va kha nang sinh tnidng nhanh, ndn ngoai kha nang ehe phli dat ddc nhanh cdn cho sinh khdi ldn trdn dan vj dien tich. Cay keo tai tuong duoc b-dng sau 2, 5 va 8 nam da cd tie dung rit tich cue de phuc hoi dd phi dit a ca 2 tang dat ciia vimg khai Ihac quang sit Trai Cau. Diy
NONG NGHIEP VA PHAT TRIEN NONG THON - KY 1 - THANG 11/2019
KHOA HOC CONG NGHt
la hudng phuc hdi dat sau khai Ihac quang sat hieu qua nang lai mdt sd khu vuc mien nui. Tap chi ^''"•'•' va bdn vung. nghiep va PTNT, 9/2013
m UBI TUMI KHAO 3. E,a„g £,inh Kim (2010). .\i;h„-n c..-.. <: * « ? 1. BdTai nguyen va Mdi hudng (2015). Thdng thuc vat de xu ly d nhiSw km loai nang ta"-"^'^^
tir 64/2015/TT-BTNMT cua Bo tivdng Bd Tai ^ ^ *^<" khoang san. Bao cio long ket Be tai nguyen va Mdi tivong ngay 21 thang 12 nam 2015: "ghien ciiu cap Nha nuo«: KC08.04/06.
Quy chuan ky thuit Qudc gia vd gidi han cho phdp 4. Dang Van Minh va cs. (2011). .Vt** i™
cua mot sd kim loai nang tiong dat (QCVN 03- bien phap .imh hoc de cai tao phuc hdi dat canh tac MT:2015/BTNMT) • sau khai tiiac khoang siin tai Thai .\i,in-en. Bao cao
2. Nguydn The Dang (2013). Thu thap, danh gia 'i'' <*• ™P Bd. Dai hoc Thai Nguyen, va tuydn chpn cay cai tao dat bi d nhilm kim loai
USING THE PLANT FOR SOIL RECOVERY AFTER THE EXPLOITATION OF IRON ORE IN THAI NGUYEN
Quach Hoaog Long"
' Thai .\i.njyen University of A'^ricullure and Forestiy
Summary
In order to provide a solution for restonng soil fertiLty after mining, an expenment of four cover crops, namely Biden pilosa, Artemisia vulgaris, Eleusine indica and Ptcm. villala, was conducted from july 2017 to July 2019 on soil after mining at Trai Cau iron mine. Thai Nguyen. The results showed thai all 4 planN had good growth and development, high biomass. so they covered the soil well and were able to attract heavy metals in the soil. All 4 plants recovers good soil fertility after 2 years of planUng. Assessment ol Acacia mangium model shows that on the post-mming land has wide adaptability and rapid growth, so in addition to the ability to cover sloping land, it also gives large biomass per unit area. Acacia mangium grown after 2, 5 and 8 years has very posiUve eifect on restonng soil ferUlity in both soil layers of Trai Cau iron ore mining area. Tliis is a sustainable and effective way to recover land after iron ore expIoitaUon.
Keywords: Post-mimng soil, cover crops. Acacia niangium. soil fertility, heavy metals.
Ngudi phin bidn: TS. Bid Huy Hidn Ngiy nhjn bii: 13/9/2019 Ngiy thdng qua phin bidn: 14/10/2019 Ngiy duydt ding; 21/10/2019
NONG NGHIEP VA PHAT TRIEN NONG THON - KY 1 - THANG 1 /2oi9
