KHOA HOC C 6 N G N G H E
TiCH HOP GIS VA DAI\IH GIA DA CHi TIEU [(VICE) TROMG XAC OflXIH DAT THICH HOP TROIXIG VAI THIEU
HUYEIV SOIV DOIVG - TIIVH B A C GIAIVG
Lfi Thi Giangl T6MTAT
Nghifin citu duoc tien hanh nham ung dung su ticb hpp cong nghe GIS va phuong phap danh gia da chi h&u (MCE) de xac dinh dien tich thich hop cho cay vai thieu. Trgng so ciia mdi chi tifiu duoc xac dmh biing phuong phap AHP va sau do tinh toan cac miic do thich hop don tinh cua cac chl tifiu bang phuang phap chuyen gia. GIS dupc su dung de xay dung ban 6.6 thich hop cho cay vai tliieu bang chuc nang chong xep cac ban clo don tinh. Vific tich hi?p GIS va danh gia da chi tieu da tim ra duoc trpng sd ciia cac chi tifiu do ddc, loai dat, dp day tang dat, thanh phan co gidi va che do nudc ddi voi cSy vai thi^u lan luot la 0,26, 0,13, 0.48, 0,05, 0,08, tir do tim vimg dat thich hop voi cac muc do rat tbich hpp (Sl), thich hpp trung bmh (S2), it thich hpp (S3) vi khflng thich hpp (N) cho cSy vai thieu huygn Son Dpng tinh Bac Giang Ian lupt la 2074,14, 8247,96, 5308,62.57936,71 ha.
Tli kh6a: Banh gi& da chi diu, (GIS) he thdng thdng dn dia ly, danh gia di't, cay vai thiiu.
1. OAT VAN fli
Son Dpng la mpt huyen mien nui n ^ a phia Jfing bic cua tmh Bac Giang, tong difin tich tu nhifin :iia huyfin nam 2012 la 84.664,49 ha, vi tri tuong ddi ihuan lpi cho vific ph^t trien kinh tfi - xa hSi va giao luu kinh tfi. Huyfin co dia huih tuong doi cao, mang lac diem khi h^u luc dia vung niii kha ro rfit, lupng mua trung binh hdng nam fliap, sd lugng ao, h6, song, suoi it va co trii luong thap, do la dieu kifin kem thuan loi cho san xuat nong nghifip; dieu kifin
?iao thong rat kho khan; dat dai co ham luong mun th^p cung gay can tro cho vific phat tnen kinh tfi - xa
|ioi ciia huyen. Nen kinh ^ cua huyen hi truoc den nay
•:hu yfiu dua vao n6ng nghiep, trong do trong cay hang iam la chinh. Nhimg trong vai nam gan day vai thifiu 'lat d^u mang lai lgi ich kmh te cao da gop phan cai hifin doi s6ng kmh te - xa hgi cua nhan dan trong uyen. Vific dcinh gia d^t thich hgp cho cay vai thieu fi phat trien thanh cay hang hoa la mgt vific lam can jiiet dfi cung cap mgt co so hop ly cho cac quyfi't jinh su dung dat.
lU Su phat trien cua hai linh vuc GIS va MCE gop jihan dac biet quan trgng trong giai quyet bai toan uyfi't dmh da tieu chi khong gian. Trong do, GIS 6ng vai tro phan tich khong gian; MCE dong vai tro ian tich da Ihugc tinh, danh gia va xac dinh mtic do J tien cua cac phuong an quyet dinh. Mo hinh tich Dp GIS va MCE la qua trinh ket hgp giiia dii lieu
khong gian va qua trinh danh gia cua ngucri ra quyfit dinh. Kha nang hifip luc giiia GIS va MCE dem lai lgi ich to lon trong nghien cuu ung dung GIS va danh gia da tieu chi vao cac linh vuc danh gia kha nang thich hgp d^t dai (Malczewski, 1999 [7]; Lootsma, 1999 161; Zopounidis va Pardalos, 2010 [10]).
Muc dich cua nghien cuu nay nham tim ra trgng so cua cac chi tieu danh gia dat thich hgp cho cay vai thifiu tai huyfin Son Dfing tinh Bac Giang bang viec ticb hgp GIS va MCE.
2. PHUDNG PHAP NGIflHi CUU
Phtrong phap danh gia da hfiu chi (MCE) la mgt ky thuat phan tich to hgp cac tifiu chi khac nhau de cho ket qua cudi cimg, ting dung phuong phap AHP de xac dinh tam quan trgng tuong ddi cua cac phuong an dua vao su so sanh cap doi (Saaty, 1997, 1980,1996 [8]). AHP tiep can van dfi theo ca 2 each:
tifip can hfi thdng qua so dd thu bac va tiep can nhan qua thdng qua so sanh cap doi.
Phuong phap nay bao gdm 3 buoc [7]:
Buoc 1; So s^nh cjg) ddi Al
A2 A3
Al 1 l / a , 2 l / a , 3
A2 ai2 1 1/223
A3 Sn a?!
1
Ma tran so sanh cap doi la ma tran dot xiing.
Miic do quan trgng cua cac phuong an dugc chia thanh 9 muc quan trgng tang dan tir it quan trgng hon den rat quan trgng hon.
Ipc vi^n Nong nghifip Viet Nam
[/JONG NGHIEP VA PHAT TRIEN NONG THON - KY 2 - THANG 1/2015 35
KHOA Hpc CONG N G H t
Bil6c 2: Tinh trpng s6
Tr^n ca sa ma tran so sanh tinh dupc miic dp quan trpng cua cac phuong an. Qua trinh tinh toan nhusau (Saaty, 1996) [8]:
• DM k . 1, khi do ma tran so sanh la [P'l - [a,l (ma tran vuong: nan)
(1). Xet buoc lap thli k:
T i n h P ' - l P " ] ^
Tong hang; T,%.,a„ (i = 1,2 n) Tinh timg gia tri cua vector u-.^ = y . ^ t
Xac dinh duoc vector [IV") = [wj^w^.-.w!;]' (2) Neu [W] - [W'l^O, dat k : - k+1 quay lai (1); nfo [W"! - [ W ' l - 0, trpng sp can tinh la [W].
Bu*c 3; Tinh tJ sd nhit quin CR
Ta cp; [P'l X [W] - X ^ . m (>™.: la gia tri rieng cua ma tran so sanh [P']).
Tinh vector nhat quan (Consistency vector):
Hxliv>l
dp doc, ch^ dp nuoc, flianh phan ca gifti va da c tang dat dupc phan cip (bang 1).
[C]-- TinhA™^ = c.l''.
' vai vector [Cl = [Cj C2...
Tinh clli sp nhat quan: CI =
Chi sd ngiu nhi&n (RI) tra tir bang chp san.
Ty sd nhat quan: CB = - {%).
Neu CR > 10% thi su nhan dinh la ngiu nhien, can dupc thuc hien lai buoc 1.
Ndu CR < 10% thi [W] la bp trpng sd cin tim [3, 51.
D^ chuin hoa miic dd thich hop ciia cac cap chi ti6u ddi vdi loai hinh vai thieu, phuang phap chuyen gia da dupc sii dtmg dd tinh toan gia tri Xi, miic dp thich hop tii cao xudng thap duoc tinh bang gia tri phan tram vdi 2(1-100%. Tit dd tinh duoc gii tri thich hop cho cac ddi tupng bing cdng thiic:
Si-'Z(W,xX,) vaii=l....n
Tich hop giira danh gii da chi tidu va GIS se cho ra la bin dd thich hpp cho cac loai hinh sii dung dat cd gii tri tir 0 den 1,0. Sir dung phuong phip phan ldp lai trong GIS de tao ra ban dd thich hpp ciia cac loai sudung daL
3.llfT(|UiillieHBIGUU
Trdn dia ban huydn Spn Ddng, chpn 5 chi tieu dd danh gii dit dai chp cSy vai thieu, do la: Ipai dat.
Phan dip 1. lx>ai dat
• Dat phil sa ngoi sudi (Py)
• Dat thung long ddc tii(D)
• Dit dd vang trgn da set va bien chat (Fs) - Dat do vang bien ddi do Udng Ilia nudc (FD -Datvang nhat tren da cit (Fq) -Dit miin vang nhat tren da cat (Hq) 2. Thanh phin cagidi - Thit trung binh (d) - Thit nhe (c) -Catpha (b)
Ma G Gl G2 G3 G4 G5 G6
C Cl Ci C3
Phan cip 3. Dg day ting dat
>100 -50-100 -<50 4. Chd dd hidl
Tudi chu d6ng Tudi l)an chu dpng Nhd nudc trdi.
5. Do ddc
• 0"-8"
-8°-15°
-15°-25"
->25'
Ma D Dl D2 D3 I 11 12 13
SL SLI SL2 SL3 SL4 Ung dung phuang phap AHP (Saaty, 1980), thifit lap ma frgn so sanh cap ddi, tren co sd do sii diing phan mem IDRISI tinh dugc trgng sd cua cac chi tieu danh gia: W,,= 0,26; WG= 0,13; WD= 0,48; Wc= 0,05;
Wi= 0,08, chi sd nhat quan CR=0,07. ,, BMg 2. Ma tran so sdnh cgp ddi
DO ddc Loai dit D6 dating
dit "
TPCG Chddd nudc
ddc 1 1/3 3 1/5 1/5
Loai dit 1 5 1/3 1/3
Dp day ting dit
1 1/7 1/5
TPCG
1 3
Chddd nudc
1 Tiong,
sd 0,26;
0,13, 0,48 0,05' 0,081 Voi cac trgng sd cho cac yfiu td (Wk), cimg v6i cac gia tri (Xi) the hifin miic do thich hgp ciia timg cap chi tieu dugc xac dinh bang phuong phap chuyfin gia, vific xac dinh Xi dua tren yeu cau sii dung dat cua cay vai thifiu dugc thfi hifin o bang 3.
Bing3.Y6uc4u
Sl 52 S3 N
Lo?idit G1,G3 G2 G4,G5,G6
su dung dit c&a TPCG
Cl C2 C3
DO diy ting dit
Dl D2 D3
ciiy vii ChSda nudc
11 12,13
thi&l DO ddc S U SL2 SL3 S U
I'l
36 NONG NGHIEP VA PHAT TRIEN N O N G THON - KY 2 - THANG 1/2015
KHOA HOC CONG NGHfi Tu d6 xac dinh gia tri Xi (%), gia tri thich hop 5,
dugc tinh theo cdng thiic S/^W^xX^ Kfit qua dugc the hifin 6'bang 4.
Bang 4. Gi6 Ihj thich hop theo tiing miic dd ph&i c ^ cua tiing chi tifiu
Ma Gl G2 G3 G4 G5 G6 Cl C2 C3
Xi (99 30 20 30 10 5 5 55 35 10
s,
0,04 0,03 0,04 0,01 0,01 0,01 0,03 0,02 0,01
Mi Dl D2 D3 11 12 13 SLI SL2 SL3 S U
Xi(99 55 35 10 55 35 10 40 35 20 5
s,
0,26 0,17 0,05 0,04 0,03 0,01 0,10 0,09 0,05 0,01 Sli dung chdng xep ban dd de xay dung dugc ban do thich hgp dat dai trdng vai thifiu, sii dung phuong phap phan ldp theo cac thang phan lop.
Thang phan ldp duoc xay dung hang each chay thii trfin phdn mem nhieu gia tri khac nhau va tham khao cac chuyfin gia de chgn ra cac cap thich hgp nhu sau;
- Rat thich hgp (Sl); cd gik tri ldn hon hoac bang 0,47.
- Thich hgp trung binh (S2): cd gia hi tir 0,36 dfin 0,47.
- it thich hop (S3): cd gia hi hi 0,29 den 0,36.
- Khdng thich hgp (N) cd gia tri bfi hon 0,29.
Difin tich cac mtic thich hgp theo ban do tren ciing da dugc tinh toan, ket qua dugc thfi hifin d- bang 5.
Bang 5. Difin tich trdng v ^ thich hgp & cac miic dp khac nhau
STT 1 2 3 4
Miic do thich hop Ritfliichhpp(Sl) Ihich hpp trung binh(S2) it thich hpp (S3) 2idng thich hop (N)
Tdng
Di^n Uch (ha) 2074,14 8247,96 5308,62 57936,71 73567,43
Tyld
(%)
2,82 11,21 7,22 78,75 100,00
Bang 5 cho th^y ddi vdi cay vai thieu, difin tich khong thich hgp chiem dien tich ldn nhat la 78,75%;
difin tich rat tihich hop chiem difin tich nhd nhat, chi cd 2074,14 ha, chiem 2,82%; dien tich thich hgp himg hinh va it thich hop lan lugt la 11,21% va 7,22%
difin tich danh gia; vi hi cac khu vuc thich hgp do dugc the hifin tren ban dd phan hang thich hgp dat trdng vai huyfin Son Ddng, lanh Bac Giang.
Difin tich thich hgp d miic Sl thudng tap trung d cac xa Tuan Dao, Cam Dan, Que Son ...dien tich tbich hgp S2 n ^ rai rac d- mdt sd xa nhu T u ^ Dao, An Lac, Duong Huu, Thanh Son... Vific danh gia dat thich hgp trdng vai thifiu bang phuong phap danh gia da chi tieu cd uu difim hon phuong phap danh gia dat cua FAO (FAO, 1976). Neu d" phuong phap danh gia cua FAO khong xet den su hrong tac giua cac chi tifiu, xem cac chi tieu cd vai trd quan trgng nhu nhau thi a phuong phap danh gia da chi tifiu se cong hang hon d vific xet dfin t ^ quan trgng khac nhau giiia cac chi tieu ddi vdi mgt muc dich danh gia cu thd (cay vai), ndi Ifin tam anh huong khac nhau d^n muc dich danh gia the hien d cac trgng sd khac nhau. Vi vay cd nhung don vi ban dd dat cd yeu td han che la thanh phan co gidi nhung do do day tang dat chifim trgng sd Icm nen ket qua thich hop cao Sl.
4 . KET LUAN
Vific tich hgp GIS va danh gia da chi tifiu (MCE) da tim ra dugc trgng sd cua cac chi tieu dd ddc, loai dat, do day tang dat, thanh phdn co gidi va chfi do nudc ddi vdi cay vai thifiu lan luot la 0,26, 0,13, 0,48, 0,05, 0,08. Nhu vay dd day tang dat cd tam quan trgng ldn nhat (Wi=0,48), it quan trgng nhat la thanh N 6 N G NGHIEP VA PHAT TRIEN NONG THON - KY 2 - THANG 1/2015 37
KHOA HQC C 6 N G NGHE
phan Cff gidi (Wi=0,05).
Nghien ctiu da tim dugc viing dat thich hgp vdi cac miic do rat thich hgp (Sl), thich hgp trung binh (S2), it thich hgp (S3) va khong tiiich hgp (N) cho cay vai thifiu huyfin Son Dgng tinh Bac Giang vdi difin tich lan lugt la 2074,14, 8247,96, 5308,62, 57936,71 ha. Nhu vay vific tich hop gitia GIS va MCE cung cap mgt cong cu huu hifiu trong vific danh gia dat thich hgp ma cd xet dfin su anh hudng khac nhau ctia tiing chi tifiu danh gia ddi vdi mgt mtic dich cu thfi.
TM UEU THAM KHAO
1. Nguyfin Kim Loi (2006). Ung dung GIS b-ong quan ly tii nguyen thien nhidn. NXB Nong nghifip TPHCM.
2. FAO (1996). Agro-ecolo0cal zoning guidelines. FAO Soils Bulletin 73.
3. Goodwin and G. Wright (1998). Decision analysis for management judgment England; Wiley.
4. J. Ronald Eastinan (2009). IDRISI Taiga Tutorial. Clark University, MA, USA.
5. C. W. Kirkwood (1997). Strate0c dedsion making: multiobjective decision analysis with spreadsheets. CA;Duxbury Press, Belmont.
6. F. A. Lootsma (1999). Multi-Criteria Decision Analysis visa Ratio and Difference Judgment Kluwer Academic Pubbsher, Netherlands.
7. Malczewski, J. (1999). GIS and Multicritena Dicision analysis. John Wiley&Sons.
8. Saaty T . L . (1996). The Analytic Hierarchy Process. McGraw Hill, 1980 reprinted by RWS Pubhcations, NewYork.
9. Voogd H. (1983). Multi-Criteria Evaluations for urban and re0onal planning. London Princeton Univ., London.
10. Zopounidis C. and P. M. Pardalos (2010).
Handbook of MultiCriteria Analysis, .^plied optimization Spring, er, USA.
INTEGRATING GIS AND MULTE-CRITERIA EVALUATION (MCE) IN DETERMINING SUITABLE LAND FOR LYCHEE AT SON DONG DISTOICT - BAC GIANG PROVINCE
Le Thi Giang Summary
The study was conducted to integrate appUcations of GIS technology and methods for Multi-Critena Evaluation (MCE) to identify areas suitable for lychee trees. Weighting of each criterion is determined by the AHP method and then calculating the suitable level of the criteria by expert: method. GIS is applied for building suitable maps for lychee trees by using overlay function. The integration of GIS and multi-criteria evaluation has found the weight of the target slope, soil type, soil depth, texture and irrigation for lychee trees respectively 0.26, 0.13, 0.48, 0.05, 0.08, then find suitable land to levels that are suitable (Sl), the appropriate medium (S2), less suitable (S3) and not suitable (N) for lychee trees Son Dong district, Bac Giang province respectively 2074.14,8247.96, 5308.62,57936.71 ba.
Keywords: MCE, GIS, land evaluation, lychee.
Ngudi p h ^ bifin: TS. H o ^ Tuan Hifip Ngiy nhan bai: 5/9/2014 Ng^y thdng qua pUn bifin: 6/10/2014 Ng^y duyfit dang; 13/10/2014
38 NONG NGHIEP VA PHAT TRIEN N O N G THON - KY 2 - THANG 1/201S
