KHOA HOC C 6 N 0 NGHt
AIXIH HUOIXIG CLIA MOT SO TRAIVG THAI THAIVI THIJC V A T DEIXI MOI TRUOIXIG D A T TAI X A V A Y IXIUA,
HUYEIXI D A B A C , TIIXIH HOA BIIXIH
Nguyfin M i n h T h a n h S D u o n g T h a n h H4i^
T6MTAT
NghiSn a i u danh gia Anh h u o n g cua mot s6 trang thai tham thuc v§t d^n moi truong di.t d u ^ ti^n h ^ h trong th6i gian tir 2011 d^n thang 5 nfim 2013 tai xS Vdy Nua, Da Bkc, H6a Binh. K^t qua nghiSn cmi cho thdy: N^u giam dO tan che tu 0,7 - 0,8 xuong 0,5 - 0,6 thi x6i mon tang 123,7% -149,7% (voi rimg tu nhien) vk 318,5% viM t r ^ g thai trang co. T ? I^ luong nuoc gift hiiu hiSu ciia vat roi rung tir 187,81% (trang co), d^n 320,72% (rung giau); luong nuoc gift hftu hi§u cua v | t roi rung dao dpng 4,32 - 22,59 m^/ha, trung binh la 11,04 m ' / h a , tuong duong v6i mOt trSn mua 0,432 - 2,26 mm. DO xop tang 12,3-14,8% (rimg t v nhiSn), 6,98%
(njng l u 6 n ^ \k Uang co cky byi la 2,26%. DO kn dkt thay doi 0.05 - 0,25%. Do pH thay d6i kh6ng dang k^.
H i m lugng chdt hftu c o tang gin 1% (rimg gidu), c6n a trang co cSy bm miic tang (0,03%) thdp hon 33,33 lan, a trang co lai giam 0,02%. Dam dk tiSu a trang co giam 0,39 m g / 1 0 0 gam ddt, b rimg giau tSng 1,65 mg/100 gam ddt, a rimg trung binh tSng 1,11 mg/100 gam ddt, a rung ]u6ng tSng 0,14 mg/100 gam ddt, b i n g 14%. Lupng PjOstang nhi^u nhdt b trang fliai rimg giau (0,41 m g / 1 0 0 gam ddt), b4p theo la rimg trung binh (0,24 mg/100 gam ddt), thdp nhdt b trang co (0,07 mg/100 gam ddt). Lugng K2O tang cao nhdt 6 rimg trung binh la 2,22 m g / 1 0 0 g a m dat, ti^p theo la rimg ngheo 2,1 mg/100 gam ddt, a rimg giau Id 1,71 mg/100 gam ddt, thdp nhdt a trdng c6 vk rimg ludng lk 0,05 mg/100 gam ddt. K^t qua nghiSn cuu cho thdy r6 i n h huong cua ldp phu thuc vSt d^n moi t a r i n g ddt, dky la nhSn t6 anh huong lon nhdt d^n nang sudt, sdn lugng cSy trong vi din sdng ngu6i dan dia phuong.
Tir kh6a: Anh hudng, tr^ng thai tham thuc v$t, mdi trudng dat, tinh chit dit
1. BAT VAN D^
T r o n g n h u n g n S m q u a , vi^c q u a n ly v a s u d y n g b^n viing d a t c a n h tdc, d $ c b l ^ t la v i m g d d t doc, c h u a dupc quan t a m d u n g m i i c . H a n g trfim h 6 c t a r u n g t u nhifin b j t ^ p h d h a n g n S m l a m c h o d i § n tich d a t tr6ng d6l niii t r p c n g ^ y c ^ tflng h o a c t h a y vao d o \k n h a n g dl$n tich r i m g h-6ng k 6 m c h d t l u p n g , k h a ndng bao v0 ddt t h d p . H i ^ n t u g n g x 6 i m b n d a n g x d y ra mgnh, m6i n 3 m h a n g n g h m t ^ d ^ t m d u m& h i x b i mdn, n i a troi, l a m c h o ddt h\ m a t d a n k h a n S n g c a n h tdc. T r o n g sdn x u d t n b n g l a m n g h i d p , d d t dai Id c b n g cy sdn x u a t vb c u n g q u y g i d vd k h b n g t h ^ t h a y t h ^ , k h b n g c h i m a n g lai c h o c o n ngiroi c d c s a n p h d m h b n g trpt m d c h i i n g c b n a n h h u o n g t n r c ti^p v a cb tinh quy^t djnh d ^ n c u p c s b n g c u a c o n n g u b i t h b n g qua cdc y^u t6 n h i r n d n g s u d t c a y t r b n g , h a n hdn, IQ lyt, sgt lb d d t . .
V i y N u a Id m 0 t x d t h u p c v u n g l b n g h o t h u y d i ^ n Hda Binh cb dja h i n h k h d p h i i c t ^ p , d p d o c ldn t r u n g binh 13 - 35", t u y n h i d n d i ^ n tich n i n g t y n h i d n c b x u h u b n g giam m a n h . S a n x u d t n b n g n g h i d p d g t n d n g sudt thdp d o d d t b) x b i m b n m a n h , n g h d o d i n h
' Tmimg Dpi hpc Lfim nghi?p ' NCS Trudng Dpi hpc Ldm nghidp, Tpp chi N6ng n ^ i ? p vd PTNT
d u b n g , dbi s b n g ngiroi n b n g d d n c b n n h i ^ u k h o k h d n . D u b i d d y t r i n h h a y v ^ s u t h a y d o i m b t s 6 tinh c h a t d i a d d t d u b i m b t s b t r a n g thdi t h d m t h u c vdt b k h u v u c x d V a y N u a t r o n g thbi g i a n tir n d m 2 0 1 1 d e n n d m 2013. K ^ t q u a n g h i d n ciiu c h o thdy rb vai t r b ciia Ibp phii t h u c v^t d ^ n m b i t r u d n g ddt, ldm c a s o d^ x u d t cdc b i d n p h d p q u a n ly s u d y n g ddt mOt c d c h h p p ly vd hidu qud.
Z. Ddl TIIONG VA PHUONG PHAP NGHiN Cini 2 . 1 . D d i h i p n g
- 7 t r a n g thdi t h a m t h u c vdt r i m g : IWmg t u n h i d n t r a n g thai n g h e o , r i m g t y n h i d n t r g n g thai t r u n g b i n h , r i m g t u n h i d n t r a n g thdi gidu, r i m g t r b n g l u b n g , r i m g t r b n g k e o tai t u p n g , t r a n g c 6 cay byi, t r d n g cb.
- T h b i g i a n n g h i d n c u u tir t h d n g 3 n d m 2011 d^n t h d n g 5 n d m 2 0 1 3 .
2.2. P h m m g p h ^ n g h i d n cihi
- K^ thira, t h a m k h d o c b c h p n lpc cdc tdi Udu, k ^ t q u a n g h i d n c u u d d c b .
- P h u o n g p h d p d i ^ u t r a c d u t n i c t h a m t h u c vdt trdn b tidu c h u l n ( O T C ) : dbi v b i r i m g t r b n g di$n tich b Id 500 m ^ r i m g tir n h i d n p h u c h b i Id 1.000 m'' vd t r a n g c o , cdy b y i , d a t t r b n g Id 100 m^. S b b tidu c h u d n d u p c t h i ^ t l$p Id 1 8 (5 ti-gng thdi t h d m t h u c v^t x 3 1 ^ ldp = 15 b, h d n g c 6 c d y b u i 2 b vd t r d n g CO l b ) .
N O N G NGHIDP V A PHAT TRI^N N 6 N G THON - Kt 1 - THANG 10/2013 107
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Trtn cac OTC do d^m cac chi tiSu D,,3, Hvn, D^, s6 bui, so cay/bui (voi rung lu6ng), cic chi tifiu cay bui tham tuoi, vSt roi rung... theo cac phuong phap di^u tra lam hoc.
Di^u tra xac dinh t6c dO thsim nu6c ciia dat theo thod gian 2 Ian (thang 4 nam 2011 va t h ^ g 4 nam 2013): Sir dung ong vong khuyen, dirong kinh ben trong ong nho la 20 cm, dutmg kinh bSn trong 6ng to la 30 cm, chi& cao cac dng la 35 cm. Cic dng dupc khac vach a phia trong. Ddng dng sau xudng dat 20 cm, tuoi nuoc tir til vao dng sao cho muc nuoc trong dng ludn giir mdt lop nudc day 4 - 5 cm phia tren t^ng dat mat. Thi nghidm dupc keo dai cho ddn khi nudc thin dn dinh thi k& thtic. Tdng sd ldn di^u tra U 5 lan/d thi nghidm. Theo ddi lirong nudc thSm qua cac khoang thdi gian: 6 \hi do dau tidn, mdi lan 5 phut; 3 lan do sau, mdi lan 10 phtit; ddi vdi nhung lan tidp theo, mdi lan 30 phiit...cho den khi tdc dd tham dn dinh thi dimg lai.
Phuong phap lay miu dat va phan tich trong phdng thi nghiem (2 lan: nam 2011 va nam 2013):
Mau dat dupc lay tai cac phau didn dat a dp sau 0 -10 cm va 10 - 30 cm theo quy trinh ky thu$t. Miu dat dupc xir ly va phan tich theo cac phuong phdp sau:
+ Ty trpng xac dinh bang phuong phip:
Picnomet.
+ Dung trpng dat Dimg dng dung trpng cd thd tich 50 cm^.
+ Bd xdp (X) tinh qua ty trpng vi dung trpng.
X=(l-D/d).100:(Dladungh-pngdatvad la ty trpng dat).
+ Xac dinh chat hiru co tdng sd (0M%) bting phuong phap: Chiurin.
+ Xic dinh dam tdng sd (N%) theo phuong phip Kjeldahl.
+ PHKCI xic dinh being miy do pH meter.
+ Dam dd tidu (N, mg/100 g dat): xac djnh theo phuong phip Chiurin va Kononova.
Lan dS tidu (PjOs, mg/100 g Mt): xic djnh theo phuong phip Oniani.
+ Kali dd tidu (KjO, mg/100 g dal): xic djnh theo phuong phip quang kd ngpn liia.
Xic dinh lupng dit xdi mdn bing phuong phip dpc cpc chang diy theo hinh tam giic ddu, mdi canh dii 3 m. Ba cpc ii dinh 3 tam giic cd khic vjch 10 cm. Dimg thudc d&y dpi do khoing cich ddn mat dit 6 tung didm cich nhau 30 cm, tir do cd sd do mil dit bdi tu (+) hay bao mdn (-)• Moi d Udu bin lip 3 tam giic, thdi gian theo doi til thing 2 ddn thing 9 nam 2011 vi 2013. Lupng dat xdi mdn dupc xic djnh bing cdng thiic: A - h.D.10 (tin/ha), trong dd h li bd diy lop dat bi xdi mdn (m), D li dung trpng dat (g/cni).
Xic dinh kha ning hit nudc ciia v|t roi rting:
Xic dinh tdng khdi lupng vat roi rung theo cic phin (phan chua phin giii, phan bin phin giii vi phin phin giii), liy mau ngiu nhidn theo ttmg phin, xic dinh khdi lupng hong khd trong gid vi khdi lupng sly khd de hidu chinh. Sau khi phan chia vat roi rving theo ttmg phin, liy mau ngiu nhidn theo timg phin, mdi phin lay 03 miu (lim tuong ttr cho tit ci cic 6 thi nghidm), khdi lupng mdi miu li 1,0 kg vi hia hinh thi nghidm ngim nudc. Khpang thdi gian gian cich cho vide xic dmh li: 15 phtit, 30 phtit, 1 gid, 2 gid, 4 gid, 15 gidtvi 24 gid. Tir kdt qua thu thJp dupc, xic dinh tdc dd hiit nudc ban diu, tdc dp hiit nudc dn dmh va qui trinh tham nudc oia vit roi rung.
8. KET QUA MSHEN niu VA T)lAO UMN
3.1. D i e didm ciu tnic mdt sd trang thii thim thvc v^t khu vt;c nghidn cihi
Ket q u i didu tra dinh gii tdng thd khu vijc nghidn ciiu cho thay mpt sd tr?ng thii thim thiic v8t cd die didm chinh dupc thd hidn 6 bing 1.
Trang thai tham thuc vat Rimg giiu Rimg trung bmh Rimg nghdo Rimg ludng Rimg keo tai tuong Trang co cay bui Trang co
Bing 1. Mdt sd d^c didm 16p Ddtan
che 0,7-0,8 0,5-0,6 0,5-0,6 0,5-0,7 0,6-0,7
Dd che phii tham tuoi (%)
45-50 65-70 70-75 75-80 74-78 85 85
thim thuc vit khu vyc nghidn ciiu Khdi lupng vat roi
rung (tan/ha) 8,41 7,90 18,00 14,70 10,91 1.21
Td thinh rimg De, Sdi, Siu, Miu chd, Ch?o tia, Nanh chupt,...
Sdi, Cheo tia, Nanh chupt, Khao nudc. Ring ring
De h-ing, Thdi ba, Ch?o, Khio, Thinh nganh....
Ludng Thanh Hda Keo tai tupng
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NONG NGHlfP VA PHAT TRIEN N 6 N G T H 6 N - KV 1 - THANG 10/2013KHOA HQC C 6 N 0 MOHt
3.2. Anh huong cua dfy tdn che 16p thdm thyc vdt d^n xbi mbn ddt
Dp tan che b i & hidn cau true ciia rung trdn mdt phdng ndm ngang vd ddy cQng Id mbt nhdn to anh hubng Ibn tbi xbi mbn d d t K^t qud nghidn ciiu trdn 7 trgng thdi tham thyc vat sau 2 ldn do (ndm 2011 va ndm 2013), lirang xbi mbn dat dupc th^ hidn a bdng 2.
Bdng 2. Anh hubng cua db tdn che Ibp thdm thyc vdt d f e x b i m b n d ^ t
T l ^ g thai tham thuc vjt RiinKgjJu RtmK trunfr binh RungnRheo RLmff ludng RLmjfkeotaitupnR TiinKco Trang cdcSy byi
fio tan che 0,7-0,8 0,5-0,6 0,5-0,6 0,5-0,7 0,6-0,7
- -
Xoi mdn dat tin/ha
1,35 1,67 2.02 3,7 3,2 4,3 3,6
100
%
123,7 149,6 274,1 237,0 318,5 266,7 Bdng 3. Khd ndng hut
K^t qua nghidn cuu cho thay db tan che cua rimg cb anh hubng rdt 16n d^n xbi mbn. N^u giam db tdn che tir 0,7 - 0,8 xubng 0,5 - 0,6 thi xbi mbn tdng 123,7% - 149,7% (dbi vdi ning tu nhidn); xbi mbn ddt tdng 237% (dbi vbi rimg trbng keo tai tupng), tdng 274,1% (dbi vbi rung trong lubng), tdng 266,7% (dbi vbd trang co cdy byi) vd 318,5% dbi vbi trgng thdi trdng CO.
3.3. Anh hu6ng ci^a Ibp thdm myc d^n xbi mbn d^t
Dubi tdn rimg, lop tham muc cung cb tdc dyng phong hb tbt, th^ hidn khd ndng che phu mdt dat, han ch^ su ti^p xtic true tidp cua hgt mua tbi d a t Tliam myc cb tdc dung hiit vd giu lai mbt phdn nubc, dbng thbi lam gidm tbe dp dbng chdy mdt thbng qua db han ch^ mbt phdn xbi mbn ddt K^t qud nghidn cuu vd kha ndng hiit nubc cua vat roi rung dupc th^
hidn a hang 3.
nubc cua vdt roi ryng Trang thii vit roi rung
Thd (chua hoic it phin buy) Phin h i y khoang 30%
Phin buy khoang 40%
Phin buy khoang 60%
Khdi lupng khd(g)
200 200 200 200
Luong nudc vat roi rung da hut Khdi lupng (g)
445,92 502,26 521,04 558,60
Tinh theo % khdi lupng khd 222,%
251,13 260,52 279,30 Kdt qud cho thdy, n^u vdt roi rung a trang thdi
thfl (chua ho$c it phdn hiiy) cb th^ hiit dupc lupng nubc b k g 2 , 2 3 1 ^ khbi lupng khb cua nb (222,96%), cdn n^u v4t rod ryng dd phdn huy khodng 30, 40 vd 60% thi cb th^ hiit dupc lupng nudc tuong iing gap 2.51, 2,61, 2,79 ldn khbi lupng khb cua nb (cr day p h ^ vgt roi ryng phan giai c6 khd ndng hiit nubc lon nh^t so vdi cac phan chua phdn giai vd phdn bdn phdn giai). Ket qud hdn phu hpp vbi nghidn cuu cua tdc gia Vb Dai Hdi: "n^u v^t roi njng b trang thdi thb (chua phdn hiiy) cb th^ hiit dupc lupng nubc b4ng 1,38 ldn khbi lupng khb ciia nb (138,33%), cbn n^u Ibp thdm myc dd phdn huy 30 - 40% thi cb th^ hiit dugc lupng nubc g^p 3,21 lan" (dan theo Ngo Dmh Qu^,2008).
K^t qud cho thdy, ty Id lupng nubc giQ huu hidu vd lupng nubc giii huu hidu ciia vdt roi rung d cdc trgng thdi tham thyc vdt cb sy sai khde nhau rb rdt TV Id Iupng nubc giii him hidu ctia vdt roi ryng dao dbng tir 187,81% ( t i ^ cb), d^n 320,72% ( t i ^ g thdi r ^ g g i ^ ) , bmh qudn d^t 236,35% hay g i p 2,36 Un khtSi lupng khb cua nb. Di4u db kdo theo lupng nubc
gitr htm hidu cua vat roi rung cung khde nhau, lupng nubc ndy dao dpng 4,32 - 22,59 m^/ha, trung binh Id 11,04 mVha, tuong duong vdi mbt trdn mua 0,432 - 2,26 mm. K^t qud dupc th^ hi^n d bdng 4.
Nhu vdy, vdt roi rung eb khd ndng giu mbt lupng nudc Tit thip, ndn khong cb tdc dyng nhi^u cho vide tidu giam nubc dinh lu va luu lupng nubc lfl, cung khbng ndn coi Id cb hidu qua dbi vbi bao vd ngubn nudc vi nb khbng th^ chay vao sbng ngbi, cung khbng dupe thyc vdt hdp thu, ma chi thbng qua bbc thodt hoi nudc trd lgi khi quydn. Lpi ich ciia v^t roi rung Id d chb, nhd cb su che phii ciia v$t roi ryng md ldm giam lupng nudc bbc hoi, qua db bdo tbn nudc trong d i t
Tuy nhidn, chiing ta mdi dimg d vide xdc djnh lupng nubc hiit giu eiia vat roi ryng b mpt thdi didm thi nghidm, trong khi tinh hodn chinh tu nhidn ciia vdt roi rung vd khia canh hiit giu nudc Id d chb: lupng vdt roi ryng thudng xuydn dupc bd sung mdi, phdn hiiy vd nhd khd ndng hiit giii nudc - * bbc thodt hoi nud: trd lgi khi quy^n-»hiit giir n u d c - » . . . - » . . . t ^ ra mbt chu tiinh tudn hodn nudc khd hodn chmh.
N 6 N G NGHIDP V A PHAT TRI^N N 6 N G T H 6 N • K? 1 • T H A N G 10/2013
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KHOA H9C C 6 N 0 MOHt
Chiing ta chua lupng hda dupc lupng nuoc mi vat roi nhidu?. Vi viy mi bin chit khi ning hiit giii nudc rung cd khi nang hiit gitt, rdi bdc thoit hoi nudc tro- cua vat roi rung nhidu it bi giam di so vdi tinh hoin lai khi quydn 6 timg thdi didm, trong mdt nam li bao chinh tu nhidn ciia nd.
B i n g 4 . D d ^ Trang thii tham
thuc vdt Trang cd Trang cay bui Rung giiu Rimg trung bmh Rimg nghdo Rimg keo tai tuong Ludng
TB STD V(%) Max Min
m tif nhidn, lupng D d i m t u nhidn cua vat
roi rung (%) . 25,61 ' 28,84 34,78 31,12 32,15 35,53 31,99 31,43 3,40 10,83 35,53 25,61
nu6c gili hiiu hidi Ty Id lupng nuoc giii hiiu
hi«u (%) 187,81 196,91 320,72 263,63 201,02 280,30 204,09 236,35 51,63 21,85 320,72 187,81
I v i lupng ntfdc Lupng nudc giii hiiu hidu
(mVha)
4,32 8,22 22,59 12,64 7,65 11,48 10,39 11,04 5,79 52,45 22,59 4,32
glii toi da cua v^t T J Id lupng nudc giii tdi da
(%)
213,42 225,75 355,50 294,75 233,17 315,83 236,08 267,79 54,25 20,26 355,50 213,42
rol ryng Lupng nudc
giii tdi da (m=/ha) 4,91 9,42 25,04 14,13 8,87 12,94 12,02 12,48 6,33 50,76 25,04 4,91
3.4. Anh huteg clia tnmg thii Ihim tfavc vit ddn Kdt qui phin tich mdt sd tinh chit ly hpc dia dit mdt sd tinh chit ciia dit dudi cic trang thii thim thuc v^t trong 2 nam 2011
3.4.1. Tinh chit Iy hoc dit vi nSm 2013 dupc tdng hpp b bing 5.
Bing 5. Su thay ddi mdt sd tinh chit vjt \i dit dudi cic tr^ng tfaii thim tfaiic vjt
Trang tfaii thim tfauc velt Riing giiu Rling trung binh Rung nghdo Rtmg ludng Rimg keo tai tupng Tring cd Trang cd ciy bui
Nam 2011 Dung
trpng (g/cm=)
0,95 1,03 1.1 1,2 1,1 1,19 1,17
Ty trpng
2,16 2,2 2,3 2,38 2,29 2,31 2,28
Dp xdp
(%)
56,02 53,18 52,17 49,58 51,97 48,48 48,68
D d i m
(%)
27,1 26,4 25,8 19,4 26,6 9,2 13,1
Nam 2013 Dung
trpng (g/cm^
0,90 0,93 1,01 1,16 1,09 1,24 1,19
Ty trpng
2,52 2,32 2,44 2,47 2,52 2,39 2,37
Ddxdp
(%)
64,29 59,91 58,61 53,04 56,75 48,12 49,78
Ddam
(%)
27,35 26,49 25,9 19,50 21,70 9,15 13,3
Bdng phuong phdp nghidn oiu so sdnh vd dinh
vi trong nghidn ctiu dat, k^t qua phdn tich edc mau ddt thubc 7 trang thdi tham thuc vdt sau 2 ndm cho thdy:
Cac trang thdi tham thyc vat khde nhau d^u cd nhung anh hudng ldn nho d^n tinh chit vdt ly dit: su thay dbi ldn nhit Id cdc trang thdi rimg txf nhidn, dung trpng ddu giam 5,6 - 10,8% tuong iing vbi db xop tdng trong khoang 12,3 -14,8%. Rimg trbng keo cb db x6p tdng 9,2%, rimg tr6ng lu6ng Id 6,98%, frang thdi trang co dp xop giam 0,74% vd trang cb cdy byi do xop giu nguydn tdng khbng ddng k^ 2,26%.
DO lm dit cb thay ddi nhung str thay dbi khd nhb, Ibn nhat Id rimg h; nhidn tdng 0,25%, t h ^ nhit la trang cd dp am gidm 0,05%.
3.4.2. HAm Iupng huu covAdd ehua eua dit Kit qua phdn tich dupc th^ hidn d bang 6.
Cdc k^t qua nghidn ciiu cho thay:
- V^ do chua dit: dit 6 khu vuc cb dO chua manh nhung cb sir khde nhau rit rb vdi timg tr?ng thi tham thyc v§t. Tir ndm 2011 d^n ndm 2013 su thay doi theo db chua d ting dit m^t khbng rb r ^ . Trong cdc k^t qud phdn tich dit, dit dudi trang thii rimg gidu cb dO chua thip hon so vdi cdc trgng thi
UO
NdNG NGHIEP VA PHAT TRIEN N O N G T H O N - KY 1 - THANG 10/2012KHOA Hpc CdNGNGHl
cdn laL DO pH ctia d i t cao nhdt dupc th^ hidn d dat phy diuOc r i t lon vdo trang Ihdi tham thuc vdt Sau 2 trang co cdy byi. Khi so sdnh gid tri dO ehua giua cdc
ndm thi chting ta n h ^ thdy cb mdt su gidm nhe, ngoai trir xu hubng tdng d d i t trdng cd, rung luong vd keo tei tupng.
- V^ hdm lupng chit hOu c a Dit d khu vuc cd ham lupng huu CO dupc ddnh gia d dgng tii nghdo ddn giau
ndm tfaeo dbi d tang dit mdt cho thiy: ChA huu co tbng s6 trong d i t dirbi b edc trgng tfadi rung ty nhidn Id ldn nhat, rimg giau 5,61%, tdng g i n 1% vd th^ nhit a trang cd cdy bui chi tdng 0,03%, mtic tdng thip hon 33,33 ldn so vbi rimg giau. DJc bidt d trang cb hdm lupng chit huu ea b} gidm so vdi ndm 2011 Id 0,02%.
Bing 6. H i m lupng hfiu e a v i dd chua dit dudi c i c tran£
Trang thii tham thuc vat
Rimg ludng
Dd sSu (cm) 0-10 10-30 Tnmg bmh Keo tai tupng 0-10
10-30 Trung binh
Riing giiu 0-10
10-30 Trung binh Rimg trung binh 0-10
10-30 Trung binh Rimg nghdo 0-10
10-30 Trung binh Tring cd ciy bui 0-10
10-30 Tnmg binh
Tring cd 0-10
10-30 Trung bmh
Nam 2011 Him lupng hiru
CO (0M%) 1,6 1,11 1,36 1,97 1,18 1,58 4,86 3,53 4,20 4,21 3,05 3,63 2,78 1,87 2,33 1,87 1.21 1,54 1,82 1,13 1,48
PHKCI
3,75 3,86 3,81 3,86 3,97 3,92 3,86 3,93 3,90 3,95 3,98 3,97 3,93 3,98 3 , % 4,19 4,26 4,23 4,03 4,10 4,07
thii (faim thvc vit Nam 2013 Ham lupng hiiu
c o ( O M « ) 1,73 1,20 1,47 2,91 1,89 2,4 5,61 3,55 4,58 4,26 3,07 3,67 3,72 2,32 3,02 1,90 1,04 1,47 1,80 1,07 1,44
PHKO
3,77 3,91 3,84 3,93 4,06 4,0 3,67 3,85 3,63 3,72 3,87 3,80 3,93 3,87 3,9 4,23 4,10 4,17 4,18 4,12 4,15 3.4.3. Strbi^ dSih^ lu^mg mOt sd chit di ti^u Kdt q u i nghidn ciiu dupc tdng hpp
Bing 7. H i m fupng c i c chit dd tidu dudi mdt sd trang thii thim th^c vit Trang thii thim
thyc vit Rungludng Keo tai tupng Rimg giiu Rimg trung binh Rimg ngheo Tring cd cfiy byi Tring cd
d bing 7.
Him lupng cic chit dd tidu (mg/100 g dit) Nam 2011
Dam thuy phin 0,97 1,95 4,50 3,47 3,42 1,46 1,46
PiOs 0,46 1,61 2,51 2,45 1,98 1,05 0,96
K,0 1,67 3,44 9,73 7,44 5,03 3,38 3,16
Nam 2013 Dam tfaity phin
1,11 2,32 6,15 4,58 4,06 1,58 1,07
P,0., 0,58 1,82 2,92 2,69 2,15 1,18 1,03
K,0 1,72 3,92 11,44 9,66 7,13 3,49 3:,21 Kdt qui phin tich d i t b khu viic sau 2 nam cho
Oiiy, cic tr;ing thii tfaim thvc vit khic nhau cd svt tich lay dlnh dudng dudi dit rimg r i t khic nhau:
- Lupng dam thuy pfain d 6/7 tr?ng thii thim thvic vjt ddu ting, trir tr?ng thii tiing cd cd lupng dfun dd tidu giim 0,39 mg/100 gam dit, bing 2791; ft
N O N G NGHIDP V A PHAT T R I I N N O N G THON - Kt 1 - THANG 10/2013
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KHOA HQC C 6 M 0 NGHJ
rimg gidu lupng dam tiiuy phdn tdng nhidu nhit 1,65 mg/lOOg dit, chi^m 37%; ti^p tiieo d rimg trung binh 1,11 mg/lOOg dit, bdng 32%; thap nhit d rimg lubng 0.14 mg/lOOg d i t hlng 14%.
- Lupng P2O5 d cac trang thai tiiam tfauc vat d^u tdng nhung miic db khde nhau; tdng nhidu nhit d h ^ g flidi rimg gidu 0,41 mg/100 g dit b ^ 16,3%, ti^p theo d rung tnmg binh 0,24 mg/lOOg dit bdng 9,8%, flilp nhdt dfrang cb 0,07 mg/lOOg dit b ^ 7%.
- V^ K20: Lupng tdng cao nhit riing trung hinh Id 2,22 mg/lOOg dat, bdng 30%; ti^p tfieo d rimg nghdo 2,1 mg/lOOg dat tuong iing tdng 42%, d rimg gidu 1,71 mg/100 g ddt b ^ 18%, tiilp nhat d h-ang cd vd rimg luong la 0,05 mg/lOO g dit tuong ting ty Id%ld2%vd3%.
3.5. Anfa hudng ctia trgng tfadi tiidm tiii^ v^t d^n khd ndng tiilm nudc cua dit
K^t qua xdc djnh tdc dp tham nubc han dau dupc thi hi$n trong bang 8.
Bdng 8. T6C dO tiilm nudc ban diu oia dit dudi trgng tiidi thdm tfai^ vdt Trang thii thim
thuc vit Rimg giau Rimg tnmg binh Rimg ngheo Rung keo tai tupng Rimg ludng Tring cd ciy bui Tring cd
Tdc dd thim nudc ban diu (Vo, mm/phiit) Nam 2011
14,6 11,4 9,7 8,2 7,6 6,4 5,7
Nam 2013 15,4 11,8 10,1 8,5 7,6 6,4 5,6 Ghi chii Tlidi gian do tic dd thim U 5 phiit.
Kdt qua d bang trdn cho tfaiy cic trang tfaii tham tfauc vit khic nfaau infa faudng khi rd den kfai nang tfaim nudc cua dat Mdt sd trgng tfaii tfaim tfauc vit cd kfai ning thim nudc tang ldn (cic trang thii rung tit nhidn, rung keo tai tupng); rimg ludng vi tring co ciy bvii giii nguydn, tring cd khi ning tfaim nuoc giim.
Kdt qui niy phan inh thvrc trgng dit ftldiu vuc vi phil hpp vdi kdt qui nghidn ciiu vd xdi mdn ft phin trdn.
4.KfrLlHN
Sau tfafti gian ngfaidn ciiu tir nSm 2011 ddn nam 2013, ldp phu thuc vat ft kfau vvtc nghidn ciiu inh huftng khi rd ndt ddn mdi truftng dit
Xdi mdn dit tang 123,7% -149,7% (ddi vdi rung tti nhidn), 237% (keo tai hipng), tang 274,1% (trdng
ludng), tang 266,7% (trang cd ciy biji) vi 318,5% vdi trang thii tring CO.
Ty Id lupng nuftc giii hihi hidu cia vit roi rung dao ddng tir 187,81% (tring cft), ddn 320,72% (ritng giiu), trung binh 236,35% hay gip 2,36 lin khdi lupng khd. Lupng nuftc giii hiiu hidu dia v$t rpi njng 4,32 - 22,59 mVha, tnmg binh li 11,04 mVha, hrong duong vdi mdt trin mua 0,432 - 2,26 mm.
Do xdp tang ding kd 12,3-14,8%. Rimg trdng keo tfaay ddi 9,2%, rung trdng ludng li 6,98%, trang thii tring cd dd xdp giim 0,74% vi trgng cd ciy byi do xdp tang kfadng ding kd 2,26%.
Dd am dit cd tfaay ddi nhimg su thay ddi kha nhft, Iftn nhit li rimg hr nhidn tSng 0,25%, thip nhit li trang cd dp im giim 0,05%.
. Dd chua dit tir nam 2011 ddn nim 2013 suthay ddi theo dd chua ft tang dat m^t it thay ddi ho$c tang khdng ding kd.
Him lupng chit htiu co tdng sd trong dit dudi rimg giiu 5,61%, tang gin 1% vi thip nhit li trang cd ciy bui 0,03%, thip hon 33,33 lan so vdi rimg giau, tring cft giim so vfti nam 2011 li 0,02%.
Dam thuy phan giim 0,39 mg/100 gam dit, bing 27% (tring cd), tang 1,65 mg/100 g dit (rimg giiu), 1,11 mg/100 g dit (rimg trung binh), bang 32%, thip nhit li rimg ludng 0,14 mg/lOOg dit, bing 14%.
Lupng PPs dd tidu tang 0,41 mg/100 g dit, bang 16,3% (rtmg giiu), rimg trung binfa 0,24 mg/lOOg dit, bing 9,8%, thip nhit l i tring cft 0,07 mg/100 g dit, bing 7%.
Lupng KjO dd tidu ft rimg tTing binh tang 2,22 mg/100 g dit, bing 30%, ft rimg nghdo 2,1 mg/100 g dit, bang 42%, ft rimg giiu l i 1,71 mg/lOOg dit, bing 18%; tfaip nfait ft trang cft vi rimg ludng li 0,05 mg/100 g dit, tiong ling ty Id % li 2% vi 3%.
TItlliUTIUMKHAO
1. Bd Nftng nghidp vi Phit tridn ndng thdn, 2006. Cim nang nginh lUm nghi$p: chuong dit vi dinh dudng dit Chuong dinh hd d-p nginh lim nghidp vi ddi tic.
2. Ngd Dinh Qud, 2008. Anh hiring caa mft s6 loiu ning dSn mdi trudng dr Vift Nam. NXB Ndng nghidp Hi Ndi.
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N 6 N G NGHllP VA PHAT T R I I N N 6 N G T H 6 N - K t 1 - THANG 10/2013KHOA HPC C 6 H 0 NOHt
3. Nguyen Mmfa Tfaanfa, Duong Tfaanfa Hdi, 2013. Tinb ehit ly bda bpc ca ban cua dit dudi mdt sd tiang thAi tbam thtre vAttaixA Viy Ntra, huyin DA Bic, tinb Hda Bmh. Tap chi Nbng nghidp vd PTNT.
Sb3+4,ti^ng209-217.
4. Ld Vdn Thdng, 2013. Nghiin euu dAc didm vAt red ryng a rimg phdng hi tbuy diin Hda Binh. Bdo cdo lugn vdn thac sy Idm nghidp. Trudng Bai hpc
Ldm nghidp.
5. CIFOR, 1999. Site management and productivity in tropical plantation forest Workshop proceedings, Pietsrmaritzburg, Kerala, India.
6. Merrill R, Kaufinann and Michael G. %an, 1986. Physiographic, stand, and environmental effects on individual tree growth and growth eSSdency in suba^inefyrests. Tree Rij^iology 2,47 - 59.
INFLUENCE OFFORESTTyPESON SOILENVIRONMENTATVAY NUA COMMUNE, DABAC DISTWCT, HOA BINH PROVINCE
Nguyen Minh Tfaanfa*, Duong Tfaanfa Hai^
^ Vietnam Forestry University
^ Vietnam Joumal of Agriculture and Rural Development Summary
The study has evaluated the influence of some forest types on soil properties during the period of 2011 - May 2013 at Vay Nua commune, Da Bac district, Hoa Binh province. The proportion of effective water kept by residue fluctuates from 187.81% (savanna) to 320.7296 (rich forest), 236.35% on average or being 2.36 times of its dry weight This figure alters between 4.32 and 22.59 m^/ha, its average value being 11.04 m^/ha being equivalent to a rain fall of 0.432 - 2.26 mm. Soil porosity grows about 12,3 - 14,8% (natural forest), 6.98% (Dendrocalamus membranaceas Munro) and 2,26% in savanna and shrub forest Soil humidity changes firom 0.05% to 0.25%. pH changes insigniflcandy. The amount of organic matter increase approximately by 1% (in rich forest) and 0.03% in shrub forest but a decrease of 0.02% is seen in savanna.
Effective nitrogen in savanna falls about 0.39 mg/l(X) g soil; yet an increasing tendency is shown in rich forest (1.65 mg/lOO g soil), medium forest (1.11 mg/100 g soil), Dendrocalamus membranaceus Munro (0.14 mg/100 g soil). The amount of PjO; is highest m rich forest (0.41 mg/l(X) g solO, followed by medium forest (0.24 mg/100 g soil) and savanna (0.07 mg/100 g soil). Amount of KjO increase most in medium forest with 2.22 mg/l(K) g soil, and 2.1 mg/100 g soil in poor forest 1.71 mg/100 g soil in rich forest in turns; the lowest increase is seen in savanna sad Dendrocalamus membranaceus Munro with 0.05 mg/100 g soil. Ilie study has made clarify the influences of the vegetation on soil environment, which has flie biggest effects on productivity, yield and life of local people.
Keywords: Influence, forest types, soil environment, soilporperUes.
Ngudi phdn bi^n: GS.TSKH. D5 Dinh Sdm Ngdy nhdn bdi: 8/8/2013
Ngdy tiidng qua phdn bi^n: 26/9/2013 Ngdy duydt ddng: 2/10/2013
DQC Igi
T^p cfai Ndng nghidp vd PTNT sd 17, k? 1 tiidng 9 ndm 2013 cd ddng bdi "Xu^ nh§p khSu rau qud Vidt Nam - Tfauc trgng va ki^n nghi" trang 3-10. Nay xm dugc sua Igi nfau sau:
X U A T N H A P K H A U RAU Q U A V I ^ NAM-THUC TRANG VA KI^N NGHl Ndng Htm Tiing*'^, Hd Hgo*
' ThtdngD^ hpc Ndng nghiip Nam Kinh ClhmgQudc) ' TrudngD^hoc Ndng-LAm Bic Giang (ViitNam) VIETT^AMESE FRUTT AND VEGETABLE EXPORTS AND IMPORTS - CURRENT
S T A T U S A N D RECOMMENDATIONS
Nong Huu l\m^, Hu Hao' ' Naiijing Agricultural University (China) ' Bac Giang University ol Agriculture and Forestiy (Vietnam)
NdNG NGHllP vA PHAT TRl^N N O N G T H O N - KY 1 • T H A N G 10/2013
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