KHOA HOC
^ CAli TRLC DONG RIONG VA HE THONG THUY LOfl NOI DONG PHUC VU PHUONG THUC SAN XUAT TIEN TIEN CHO VUNG
BAC TRUNG BQ
PGS.TS T r a n Chi T r u n g , KS. Pham Van Hiep Trung tdm Tu vdn PIM Tom tat: H$ thdng thuy lgi ngi ddng Id ca sd hg tdng cd vai trd quan trong trong phdt trien sdn xudt ndng nghiep, xdy dung ndng thon mdi. Tren ca sd kit qud dieu tra tgi 3 tinh Nghe An, Hd Tinh vd Thira Thien Hui nghien ciru ndy di xudl cdu true ddng rudng yd he thdng thuy lgi ngi ddng phuc vu phuang thirc sdn xudt tien tien cho vung Bdc Trung bd. Cdu true dong rudng vd hj thdng thiiy lgi ngi ddng da kit hgp vdi giao thdng noi dong di dp dung ca gidi hda sdn xudl ndng nghiep theo quy md ldn. Cdc sa do quy hogch he thdng thiiy lai ndi ddng ddm bdo chu dgng tudi tieu cho tirng khodnh, cdc thira rudng dugc tudi tieu ddc lap cd the chu dgng canh tde khi sdn xudt khdng dnh hudng din thira rudng khde, thudn tien cho viec qudn ly van hdnh.
Tir khda: Cau true ddng rupng, he thong thuy lgi npi dong, phuffng thitc sdn xuat tien tien Summary: On-farm irrigation system is an important infrastructure foragriculture development as well as rural development. Based on results of assessing actual situation in three provinces namely Nghe An. Ha Tinh and Thua-Thien-Hue, this research proposes the farm structure and on-farm irrigation systemmeeting for advanced agriculture production in the Northern central region. The farm structure and on-farm irrigation system have been combined with farm roads to promote agricultural production mechamzationfor large scale. The on-farm irrigation planning schemes ensurefor convenient management, since these schemes can provide water to each farm plotso that each plot can be cultivated indecently, noi affecting lo the others.
Key words: Farm struture, on farm irigation system, advance production modaylity.
I, D ^ T VAN DE
H? thong c6ng trinh thuy lgi la co s6 ha tang ph\ic vy tudi tieu cho cay trong, g6p phan quan trgng iam tang nang suat, san lugng va chat lugng san pham nong nghiep. Tuy nhien, ben egnh cac h? thong thuy lgi phat huy cao c6ng suat thiet ke, con nhieu cong trinh thuy lgi dgt hi?u qua thap, chua dap iing dugc yeu cau nhi?m vy de ra, ty 1? dien tieh co tuoi dgt 80%, ha tang thuy lgi ngi dong ehua dap iing dugc yeu cau san xuat nong nghifp theo quy
Ngireri phin bi?n: PGS.TS Nguyen Tlil Quang Ngay nhgn bai: 05/8/2014
Ngay thong qua phan bi?n: 26/9/2014 Ngay duy?t dang: 24/4/2015
trinh tien tien. Ca nuoc co 234.000km kenh muang cac loai nhung mai c6 2 3 % dugc kien c6, ty le kenh muong ngi dong duge ki6n co con thip hon, chi dat khoang 16% [6]. D^ an Tai CO cau nganh thuy lgi d5 neu ro can nang cap, eai tgo co s6 hg tling thuy lgi, gin vdi xay dyng duong giao thong ngi d6ng, d6n dien, doi thUa, san phang dong mgng de eo t h i ap dyng cac phuong thiic eanh tac tien tiln, t6 ehiic lgi san xuat theo quy mo Ion, thiic diy co giai hoa, gop phan nang cao nang suit cay trong.
Nghien ciiu ap dyng cae giai phap khoa hgc cong nghe xay dung h6 thong thuy lgi ngi ddng la giai phap quan trgng d l xay dyng hoan chinh he thong thuy lgi ngi d6ng. Den nay da CO mgt so nghien eiiu ap dyng cae giai phap
30 TAP CHf KHOA HQC VA C O N G N G H E T H O Y L p i SO 26 - 2015
KHOA HOC khoa hge cong ngh^ xay dyng he th6ng thuy
lgi ngi dong, nhu nghien ciiu quy hoach thuy lgi ngi dong phyc vy cho cac mo hinh chuyin doi CO ciu cay tr6ng vimg DBSH [4], nghien ciiu hi^n dgi hoa he th6ng thiiy lgi ngi ddng cho viing DBSH [1], nghien ciiu so d6 he th6ng thiiy lgi ngi ddng cho vimg DBSCL [5].
Tren ca s6 kit qim dilu tra, danh gia tai 3 tmh Nghe An, Ha "Hnh va Thua Thien Hul, nghien ciiu nay de xuat cau tnic ddng rudng va he thong thiiy lgi ngi ddng phuc vy phuang thUc san xuat tiSn tiln cho vimg Bdc Trung bd.
II. THI/C TR^NG Hl^ THONG THUY LOI NQI B 6 N G V A CAU TRUC DONG RUONG 6 VUNG B A C TRUNG BQ + Thuc trgng he thdng thuy lgi ndi ddng:
Theo sd lieu thdng ke cua Tdng eye Thiiy lgi nam 2011, vung Bac Trung bg cd 7.502 edng trinh thiiy lgi, trong do cd 2.424 hd ehua, 1.458 dap dang, 3.100 tram bam va 520 cdng trinh tam phuc vy cho tong di^n tich tudi 654.540ha, trong do 331.270ha liia ddng xuan, 139.530ha liia he thu, 138.740ha lua mda. Theo ket qim dilu tra tgi 3 tinh Nghe An, Ha TTnh va Thira Thien Hue, eac td ehiie thuy ndng d dia phuong quan ly 2.956 cdng trinh ehiem 80% sd lugng cac cdng trinh thuy lgi, phue vu cho 40% dien tich tudi.
Sd lieu nay eho thay vai tro rat quan trgng cua cac cdng trinh tfiuy lgi ngi ddng do dia phuong quan ly hien nay. He thdng kenh muong ciia toan vung CO tdng chieu dai 22.828km da dugc kien CO 11.287km, trong do ty le kien ed hoa cac tuyin kSnh cAp 1 la 60%, kenh cap 2 la 31% va kenh e ^ 3 la 27% eho thay he thdng kenh ngi
ddng chua dugc kien cd hda nhiSu, linh trang kenh dat cdn ehiem da sd.
Ket qua dieu tra he thdng thiiy lgi ngi ddng theo tieu chi thiiy lgi xay dung ndng thdn mdi 6 45 xa dien hinh (15 xa/tmh) 6 3 tinh eho thay den cudi nam 2013 chi co 5 xa (chilm 12%) dgt tieu ehi thuy lgi. Trong do sd xa dgt tieu chi ed he thdng cdng trinh thuy lgi dam bao nang luc thiet ke dat 68%. Tieu chi kien cd hoa kenh muong dgt dugc rit thdp, 6 Ngh? An dgt 20%, Ha Tmh la 35% va Thira Thien Hul mdi dat 7%. Dae diem ve he thdng thiiy lgi ndi ddng vung Bae Trung bd dugc danh gia qua mpt sd thdng sd ve mat dg kenh tudi, khoang each eac kenh tudi mat rudng, ty le kenh tudi tieu taeh biet (Bang 1). Mat do kenh tudi trung binh ciia vung Bac Trung bd dgt 105 m/ha, trong do cac kenh tudi mat rugng la 80m/ha. Khoang each giGa cac kenh tudi mat rugng trung binh la 135m, nhieu viing san xudt con thilu kenh tudi mat rugng nen tinh trang tudi tran tir thua rudng nay sang thiia khac con phd biln. Ty 1? kenh tudi ti6u taeh biet binh quan cua vimg la 58%, nhieu he thdng con thieu kenh tieu mat mgng.
Kien cd hda kenh muong dugc cae dia phuong thuc hien theo 4 hinh thdc chii ylu la: Be tdng, gaeh xay, da xay va gach tapio, trong do hinh thUc phd bien nhit la loai hinh keiih b6 tdng (chilm 32%) va gaeh taplo (chilm 37%). Trude day, hau het cac dia phuang deu su dung ggeh taplo xay dung kenh muong dl giam chi phi dau tu xay dung. Thoi gian gin day, khi cac tinh cd CO ehe ho trg xi mang cho xay dung kenh muong thi eac dia phuang da xay dyng kenh be tdng la chu yeu.
Bang 1. Dae diem he thong thuy Igi ngi dong vung Bdc Trung bg Tinh
Nghe An Ha Tinh Thira Thien Hue Binh quan
Mat do kenh tudi (m/ha)
110 125 87 105
K/c cac kenh tiroi mat mong (m)
140 135 132 135
Ty le kenh tuoi tieu taeh biet (%)
58 60 57 58
TAP CHl KHOA HQC VA C O N G NGHf TH J Y LOI S(5 26 - 2015
KHOA HOC l i i ^ E I 3 ! B U i
+ cdu true ddng rudng:
Tir nam 1996 khi thuc hi?n chinh sach khoan rudng cho hg nong dan, cac tinh viing Bac Trung bd da thue hien viec giao rudng dat cho ngudi dan san xuat, moi hd cd 7-10 thua rudng, cd dien tich trung binh la 300-500m ddi vdi dat Ilia va 200-300 m^ddi vdi dit rau [3]. Sang giai dogn 2000-2010 cac tinh bat dau thyc hien ddn dien ddi thira nen dong rudng da bdt manh miin, tnmg binh s6 thua/hg giam tii 50-70%, dien tich cac thua tang tir 100-150%. Nha thuc hi?n ddn diln
ddi san xuat hieu qua, dit ndng nghiep dugc chuyen ddi eho timg viing, tap tnmg chuySn canh theo cac thdn, he thdng thiiy lgi va giao thdng ndi ddng da ngay cang dugc cai thidn.
Tii nam 2010 den nay vdi viec phat trien ndng nghiep 6 cac xa dien ra mgnh me, yen eiu ap dyng ca gidi hda vao san suat nong nghiep ngay cang cao de phat triSn ndng nghiep, hiu hit cac dia phuong tiep tye tien hanh ddn diln ddi thiia (ddn dien ddi thiia ISn 2). Sau khi thuc hien ddn dien ddi thua hien nay trung binh chi edn 3 thiia/hd, dien tieh binh quan thiia rudng la 948m^ (Bang 2).
ddi thua n6n da xuat hien cae md hinh chuyen
Bang 2. Dae diem cau true dong rugng viing BSc Trung bg
Ngh? An Ha Tinh Thira Thien Hu§
Binh quan
Dien tich nong nghiep/ho (m^)
2.127 2.250 2.100 2.159
So thiia/hp 3 3 4 3
Di?n tich thua rugng (m^)
1.057 887 900 948 Nhimg phan tich tren eho thay he th6ng thuy
l(?i npi dong vimg Bac Trung bp con t6n tai nhi6u van de. Ty le cac xa dat tieu chi thuy li?i con thip (12%) do he thSng thiiy loi npi dong chua dam bao chii dpng cap nuoc cho san xuat nong nghi?p. Tieu chi kien c6 hoa kenh muong hifn nay d?lt rdt thip. NhiSu vimg san xuat con thieu kenh tuoi tieu mat rupng, tinh trang tuoi tieu tran bo da anh huong den vi^c chu dpng canh tac san xuit nong nghiep. Man thuan giGa cac ho dung nuoc con xay ra nhu co hg gieo ma, co hp lai cay hay co thua rupng gSt cin tieu nuoc trong khi CO thua can nuoc de gieo ma nhimg h | thong thiiy Ipri npi dong hien tai ehua chii dpiig dupc tuoi, tieu. Thiia rupng hien nay co chiju dai ph6 biin tir 40-60m khong dam bao yen cau cho cac loai may co gioi san xuit nong nghipp hoat dpng hieu qua (yeu ciu chieu dai thira rupng tit 80 -100m).
m . Dfe XUAT M 6 HINH CAU T R t C D 6 N G R U Q N G V A H E T H 6 N G THUY LOI NQI D 6 N G P H V C VV PHU'ONG THirc SAN XUAT TIEN TIEN CHO VfiNG BAC TRUNG BQ
3.1 Sa do h^ thong kenh tirdi, tieu a) Yeu cdu quy hogch hodn chinh h( thdng thuy lgi ngi ddng:
Hoan ehinh hp th6ng thuy lpi npi d6ng phue vu phuong thitc san xuit tien tiSn cho vimg Bic Trung bp can dap ling dupc cac yeu ciu nhu sau:
- He thong thiiy lpi npi d6ng phii hpp voi quy hoach xay dung nong thon moi, dinh huong phat trien kinh ti xa hpi, dae biet la phat triSn nong nghiep ciia eac dia phuong.
- He thong thuy lpi npi d6ng dam bao dupe tinh dong bp voi cac quy hoach khac nhu quy hoach he th6ng thiiy lpi dia vung, quy hoach duimg giao thong npi d6t^ quy hoach su dung daJ va chuong tiinh don dien doi thua 6 cac dia phuong.
32 TAP CHf KHOA HQC VA CONG NGHE THilY LOI S(5 26 - 2015
KHOA HOC - He thdng thuy lgi ndi dong chu ddng tu6i tieu,
dam bao tudi tieu ehu dgng cho cac thua rugng ma khdng anh hudng den thua rugng liin kl dl dap ling dugc cac phuong thiic san xuit ndng nghi$p tien tiln nhu SRI, ndng - Id - phoi.
- H? thdng kenh muong ndi ddng dam bao cho viec
^ dyng ca gidi hda vao san xuat ndng nghi^.
b) Sa do he thdng thiiy lgi ngi ddng cho vung Bdc Trung bo:
+ So dd 1: So dd bd tri kenh tuoi tieu taeh biet hai ben bd khoanh
J J . 1 J _ J J 1 J J 1
* V » — * * V I * t 1 Al
1 J. _ i 1 J S T 7 '
» » 1 • - * * • • • •
t i !
v i v l V I V V | t v '
Kenh tuoi Kenh tieu Bo khoanh Bo vung
Hinh 1. Sa do bd tri kenh tudi tieu tdeh biet hai ben bd khodnh U'u diem: Chu ddng tudi tieu eho timg
khoanh. Cae thua rudng dugc tudi tieu dgc lap cd the chu ddng canh tac khdng anh hudng den thiia rudng khac, tao dieu kien thuan lgi cho co gidi hda, eho quan ly van hanh. Dudng bd khoanh 6 giiia cd the ket hgp duang giao thdng eho nmy ndng nghiep.
Nhugc dilm; Cd nhieu dudng bd khoanh, nhieu kenh mat rudng nen dien tich chiem dat
ldn (7.1%), do do tang kmh phi dau tu.
Dieu kien ap dyng: Khu vyc co dia hmh tuong ddi bang phang va cd xu hudng ddc mdt chieu. Phil hgp cho cac vung trdng lua chat lugng cao, vung xen vy lua va mau, vung chuyen cay mau, cac canh ddng mlu ldn.
+ So dd 2: So do bd tri kenh tudi tieu taeh biet, hai khoanh rudng chung mgt kenh tieu 1 1 1 1
I I I . 1
I I 1 ; • A.
I I 1 1 1 i ' 1 1 1 1 1 x l s ' s ' i l j l i f ,
1 1 1 1 1 I t 1 1 1 1 '
t 1 1 ! 1 ' , ;
t 1 t 1 « : f - » . f 1 * ? ' J 1 * 1 » 1 i 1 i , . i '
Kenh tuoi Kenh tieu Bo khoanh Bo vung
Hinh 2. Sa do bd tri kinh tudi tieu tdeh biet. hai khodnh rugng chung mdt kenh tieu
TAP C H l KHOA HOC VA C O N G N G H £ THUY LOI S 6 26 - 2015 33
I KHOAHOC
Uu dilm: Chu dgng tudi tieu, tgo dieu ki6n thuan lgi eho eo gidi hda, thuan tien cho quan ly van hanh, dien tich dat chiem 6.5%, thap ban so dd 1 do bd kenh tieu khdng kit hgp dudng giao thdng.
- Nhugc dilm: Phai cai. tao lai mat mdng neu dilu ki?n dia hmh khdng cho phep, bd kenh khdng kit hgp dudng giao thong se khdng
thugn lgi cho mgt sd khau trong san xuat.
Dilu kien ^ dung: Khu vuc cd dia hmh tuong ddi bang phlng co thi tiSu vl mgt phia hoac dja hmh cd dgng lan sdng. Kenh tuoi bd tri tren dBnh sdng, kenh tieu bd tri dirdi chan sdng.
+ So dd 3: So dd bd tri kenh tudi tieu kit hgp cho timg khoanh rudng
Kenh tuoi tieu ket hpp Bo khoanh Bo viing
Hinh 3. Sa do bd tri kenh tuai tieu kit hgp cho timg khodnh rudng - Uu dilm: Thugn ti?n cho ca gidi hda va quan
ly van hMi, chilm dien tieh dat thip (6.7%), giam sd lugng kenh so vdi 2 so do tren, kinh phi dau tu thap.
- Nhugc dilm: Miic dg chu dgng trong tudi tieu khdng cao, lugng nude trong kenh ldn, khi ngudn nudc hgn ehe se gay khd khan cho viec lay nudc, thai gian tieu nuac eham.
- Dilu kien ap dyng: Khu vuc cd dia hinh tuong ddi bang phang vimg ddng bang, eae khu vue yeu cau miic dg tudi tieu ehu ddng khdng cao phii hgp cho vung chuyen liia hoac cd the ap dyng cho vung nudi trdng thuy san.
c) Phgm vi kien cd hda kenh
Kien cd hda kenh muong la giai phap quan trgng nang eao hieu qua tudi tieu ciia he thdng thuy lgi ndi ddng, tuy nhien, van dl dat ra la pham vi nao thi can thue hi^n kien cd hda kenh mat mgng hay kenh cap nude cap cudi cimg.
xay dyng kien ed kenh mat rudng dan din dau
tu Ion, trong khi dd 6 phgm vi phii hgp eac tuyin kenh mat rugng la kenh dat van phat huy dugc hi?u qua tudi tieu. Hon niia, cac kenh dat con cd tac dyng bao v? mdi truong sinh thai eho mgt sd logi sinh vat tdn tgi tren ddng ruOng.
Hien nay, mdt s6 dia phuang da cd van ban quy dinh pham vi thuc hi6n kien c6 hda kenh de ho trg xi mang cho xay dung k6nh muong nhu 6 tinh Thira Thien Hul la kenh tir 5ha trd 16n hay 6 Ngh? An la k6nh tir lOha tra len. Tren co s6 phan tich thuc trgng hf thdng thuy lgi ndi dong cung nhu chii truong thue hien kien co hoa kenh muong cua cac dia phuang thi pham vi can thuc hien kien cd hda kenh mat rugng hay k6nh cap nudc cap cudi cimg la Sha trd len doi vdi viing mien nui va lOha trd len doi vdi vung ddng bang la phii hgp cho viing Bic Trung bg.
3.2 Be xuat cau true dong rugng cau tnic ddng rudng ciing la yeu td quylt dinh den hieu qua ciia he thdng thiiy lgi ngi ddng do
34 TAP CH( KHOA HOC VA C O N G N G H E THUY LOl S6 26 - 2015
I KHOAHUC ^ j . ! i ! c l J I . 1 ! l = ^ anh hudng toi so dd bd tri he thdng kenh ndi dieu tra,_cau tnic dong rudng phu hgp cho he ddng, b a vimg b6 thua va kha nang ap dung co thdng thtiy lgi ndi ddng dap ung phuang thuc giai hda vao san xuit ndng nghiep.Tren co sd san xuat tien tien cho vimg Bac Trung bd dugc phan tich thuc trgng ddng rugng d cac tinh de xuat nhu d Bang 3.
Bang 3. Cac thong so ve eau triic ddng rugng cho vung Bac T r u n g bo TT
1 2 3 4 5 6 7
Chi tieu Dien tich thira Chieu dai thira rupng Chieu rpng thiia rupng Khoang each 2 ha khoanh Chieu rpng bo khoanh Khoang each giita 2 bo viing Chieu rpng hiy vimg
Don vi m^
m m m m m m
Viing dong bang 2.000- 4.000
80-120 20-40 80 -120
2 - 4 250-300
4-6
Vimg trung du, mien mil 1.500-2.500
70-90 20-30 70-90 2-3 400-600
3-4
3.3 Ap dung quy hogch hS thong thuy loi uQi dong cho xa Diln Phiic
Xa Dien Phiic huySn Dien Chau, tinh Nghe An dugc chgn la xa diem de ap dung xay dyng hoan chinh h$ thong thiiy lgi ngi ddng. Xa Dien Phiie eo dia hinh bang phang dai dien cho viing ddng bSng d viing Bac Trung bg xa
vdi dien tich ty nhien 45.606 km , trong do dien tich nong nghiep 331,4ha, dien tich trdng Ilia 185,6ha. Ket qua ap dung so do bd tri kSnh tudi tieu taeh biet hai ben ba khoanh (Sa do 1) de quy hoach he thdng thuy lgi ndi ddng cho khu mau san xuat tham canh lua dugc the hien 6 Hinh 4.
F^-
; ' H" > • - *-^
«
i « «
-f—^
1 — —
- * -»
t
»
t
•
«
•
«
]I
"- (
7uni
1
1 ., . 1 .
1 ^ 1 " "
1 - "
1 " "
1 **
1 *"
\r
]
[
' 1
Hinh 4. Ap dung quy hogch he thdng thuy lgi ngi ddng cho xa Dien Phuc.
(a) Hien trgng vd (b) quy hogch
TAP CHt KHOA HOC VA C 6 N G N G H ^ THUY LOl S(5 26 •- 2015 35
I KHOAHOC | ^ J . I . M J . < M ! I = ^ Sau khi ap dung quy hoach, dien tich thua rupng la til 2000m'- 3000m'c6 chiSu rpng trung binh tir 20 - 30m, chi6u dai tit 80-
100m dam bao dap ling yeu cau cho viec ap dung CO gioi hoa san xu4t nong nghiep.
Tirng thua rupng dupc tuoi tieu rieng biet nen co thi chil dpng canh tac ma khong anh huomg dSn thua rupng liSn ki, thuan tien cho viec ap dung cac phuong phap tuoi tiet kiem nuoc nhu nong 16 phoi, SRI.
Dutmg bo khoanh 6 giira co the ket hop ducmg giao thong cho cac may nong nghiep, khoang each giita cac bo viing, bo thua diim bao cho viec di lai, van chuyen san pham nong nghiep Ihuan tien.
IV. KET LUAN
Tren co so kSt qua diiu tra tai 3 tinh Nghe An, Ha Tinh va Thira Thien HuS, nghien cilu nay da dS xuit cSu hue d6ng rupng va he th6ng thuy loi npi d6ng phuc vu phuong thirc san xuat tien tien cho vimg BJc Trung bp. Cdu tnic dSng mpng va he th6ng thuy lpi npi dong da g§n vcri san phSng, cai tao d6ng rupng, k6t hpp voi giao thong npi dong dl ddy manh co gioi hoa, canh tac theo quy n\b Ion. Cac so d6 quy hoach he thong thiiy lpi npi d6ng dupc dl xuit dam bao chii dpng tuoi tieu cho timg khoanh, cac thua rupng dupc tuoi tieu dpe lap CO thi chu dpng canh taeh khi san xuit khong anh huong din thua rupng khac, tao dilu kien thuan lpi eho ca gioi hoa san xuat nong nghiep cung nhu cong tac quan ly van hanh.
TAI LIEU THAM KHAO
[1] Nguyen Tuin Anh. Nghien ciru giai phap hien dgi hoa he thong thiiy loi npi viing DBSH, 2013.
[2] Bp Nong nghiep va PTNT. Tuyin tap tieu chuan co dipn nong nghiep Viet Nam - tap 1, 2002.
[3] Dao The Anh. Nghien cuu thuc tien don dien doi thiia a mot so tinh va de xuat cliinh sach don dien doi thira nang cao hieu qua sii dung dat o DBSH, 2004.
[4] Doan Doan Tuan. Nghien ciru cac giai phap thiiy lpi phuc vu chuyen doi co cau cay trong viing DBSH, 2008.
[5] Le Sam. He thong thiiy lpi viing DBSCL. Nha xuit ban nong nghiep, 2009.
[6] Tong cue thiiy lpi. Bao cao dieu tra hien trang thiiy lpi toan qu6c, 2013.
36 TAP CHl KHOA HOC VA CONG NGHE T H O Y LOI Sl3 26 - 2015
