Nguyen Hai Hda Tap chi KHQA HQC & CONG NGH? 173(13): 2 5 - 3 0
StJ" DUNG ANH PLANETSCOPE XAY DUTVG BAN DO THAM PHU XA VEN BIEN T H U Q C TINH THANH H 6 A VA NINH BINH
Nguyen Hai H&a Truang Dgi hoc Lam nghiep Viet Nam T O M T A T
Vi6c ling dung c6ng ngh§ GIS v i tu liSu vien tham c6 dp phan giii cao cho ph^p danh gii nhanh hi?n trang thim phii ven bien voi dp chinh xac cao. Ket qua xay dyng bin do hien trang thim phii cac x i ven biin bing tu lieu anh PlanetScope nim 2017 thong qua chi s6 thyc vat cho dp chmh xic rat cao tr6n 95,0%, 6^c biet phuong phip phin loai bing chi s6 SAVl (Soil Adjusted Vegetation Index) (97,1%) cho dp chinh xic cao hon chi s6 NDVI (Normalised Difference Vegetation Index) (95,5%). Theo chi so SAVl, dien tich dit che phii bdi thyc vat la 2054,0 ha (18,6%), dien tfch dit tring v i dit tho cu chiem 4677,5 ha (42.4%), diSn tfch che phu bdi nude la 4299,0 ha (39,0%).
Ket qua nghien ciiu l i co so khoa cho viSc qui hoach phit triSn va quan ly hoat dpng sir dung dit viing ven bien khu vyc nghiSn ciiu.
Tir khda: Chi so thuc vat, PlanetScope, sir difng dat, thdm phii, Thanh Hda, Ninh Binh D A T V A N DE
T u lieu v i l n tham la m6t trong nhiing thanh tuu khoa hpc khdng gian vii try dang dugc sii dung rdng rai trong nhieu ITnh vyc q u i n ly tai nguyen va mdi trudng d nhieu nude trln the gidi [1]. V i l e ling dung cong ngh? GIS va t u lieu vien t h i m giiip c i c nha khoa hgc v i nha hoach djnh chinh sach cd nhieu phuong i n lua chgn mang tinh chiin luge trong vi?c sir dyng va quan ly t i i nguyen thien nhiln va mdi trudng [6]. Do vay, GIS va vien tham dugc sii dung n h u la mgt cgng cy h i l u qua trong quan ly v i giam sat tai nguyen moi trudng hien nay.
Bk t i n g c u d n g tinh h i l u qua cdng t i c quan ly boat ddng sii dung dat thi viec xac dinh d i l n tich va m u c dich su dyng dat, xac djnh loai t h i m phii la dieu quan trgng. Do dd, b i n dd hi?n trang t h i m phii la tai li?u quan trgng trong cdng t i c quan ly dat dai, thiit ke, quy hogch sir dung d i t [5]. Hien nay, cdng t i c qui ho^ch sii dung d i t tai cac xa ven bien thugc huyen Nga Son va Hau Lgc (tinh Thanh Hda) va huyen Kim Son (tinh Ninh Binh) la nhu c i u c i p thiit, mgt trong nhfi-ng k h i u quan trgng ciia cdng tac nay la danh gia hien trang su dung dat ma p h u a n g tiln cua no l i ban dd.
' Tel: 0977 689948. Email: hoanh@vfu edu.vi
Tai khu vuc nghien cuu, mac du hang nam deu cd c i c bao cao v l h i l n trang c i c Idp phii v i boat dpng sir dyng dat, nhung hau h i t cac bao cao chii yeu dua tren viec do ve, thanh l$p b i n do bang p h u a n g phap truyin thong tho so, do la mpt cdng viec phiic tap, mat nhieu cong siic va ddi hdi nhilu thdi gian.
Ngoai ra, viec xay dung b i n do Idp phu doi hoi nhanh ve thdi gian, chinh xac ve loai hinh v i cap nhat ve thong tin. Do vay, v i l e nghien ciiu ling dung t u lieu vien t h i m ket hgp vdi he thong thdng tin dja ly d l xay dyng ban do h i l n trang Idp phu dam b i o tinh hien thdi, ddng bg phuc vu qui hoach bao ve he sinh thai ven b i i n la yeu cau k h i c h quan v i c i p thiit duoc dat ra tai khu v y c nghien ciiu. D l gdp phan giai quyet van tren, n g h i l n ciiu da thuc hien xay d u n g ban d o h i l n trang Idp phii thong qua chi sd thyc vat NDVI va SAVl vdi i n h PlanetScope cd do phan giai cao tai khu vuc nghien cuu, ket qua se la c o sd khoa hpc cho viec qui hoach phat trien va quan ly boat dpng su dung dat cho khu v y c nghiln ciiu.
DIA DIEM, V A T LIEU V A P H U O N G P H A P N G H I E N CUU
Dia diem nghien ciru
Doi tugng nghien cuu la cac doi tugng tham phii thugc cac xa ven bien, bao gom xa Da Lgc thugc huyen Hau Lgc, x i Nga Tan va
25
Nguyen Hai H6a Tap chi KHOA HQC & CONG NGHE \T5l^V3):2:)-3(}
Nga Thiiy thupc h u y i n Nga San tinh Thanh Hda; va xa Kim D d n g thupc huyen Kim Son, tinh Ninh Binh. D i xay dyng b i n do Idp phii, d i t i i su dung PlanetScope nam 2017 vdi do phan giai 3mx3m (Bang 01).
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Hinh 1. Khu virc cdc xa nghiin cdu ven bien thudc huyen Hgu Loc vd Nga San (Thanh Hoa); huyin Km San (Ninh Bmh)
V a t lieu n g h i l n cihi - M a y G P S G a r m i n 6 5 0 . - Phin m i m ArcGIS version 10.2.
- T u li^u anh PlanetScope nam 2017 vdi dd phin giai 3 m x 3 m.
P h m m g p h a p n g h i e n c ^ Phitffngphdp dieu tra ngoai nghiep De tai tiin h i n h dieu tra, lya chpn cac diem kiem tra (Sampling points) ngoai thuc dja d l dinh g i i do chinh xac p h u a n g phap phan lo^i anh. Phuong phap lua chgn m i u ngau nhien phan t i n g dugc sii dyng de x i c djnh cac ddi tugng toan bp khu vyc nghiln ciiu. Vi tri cac diim khao s i t dugc xac dinh tga do bang thiit bi h i thdng dinh vj toan c i u (GPS Garmin 650). K i t qua cd 300 diem dugc d i i u tra ngoii thyc dia vdi 3 Idp doi tugng. D l tai sir dung 7 0 % (210 diem) sd diem nghien ciiu ngoai thuc dia cho muc dich phan loai va 3 0 % (90 d i l m ) sd diem con lai dugc sur dyng
cho v i l e danh g i i do chinh xac phuong phap phan loai.
Phircmg phap xir ly vd phan loaidnh Qua trinh x u ly va phan loai i n h gdm 3 budc chinh n h u sau (1) Thu t h | p du lieu i n h va cac b u d c tiin xii 1^ anh, gdp cac canh anh lai voi nhau, phan tich, x u !^ dii lieu va tiin hanh giai d o i n i n h ; (2) Thanh l i p cac ban do tham phii nam 2017 thong qua chi s6 thuc VEit (NDVI- Normalised Difference Vegetation Index) va chi sd SAVl {Soil Adjusted Vegetation Index) [7, 8]. D l tiin hanh xu I^f va phan loai i n h , d i t i i su dyng phin mim c h u y i n dyng ArcGIS 10,2.
Chi s6 N D V I d u g c x i c dinh dya trln su phan xa khac nhau cua thyc v i t t h i h i l n giiia kenh p h i k h i k i i n va kenh pho can hong ngoEii, diing d i b i i n thi miic do tap trung cua thyc v^t trln mat dit. Chi sd thyc vat dugc tinh toan theo cdng thiic sau:
NDVI == (BanduiR- BandRed)/(BandNiR+ BandRed) Trong dd: NDVI la chi so thuc vat, Bandm la kenh h6ng ngoai, BandRed la kenli mau do, G i i tri cua chi so t h y c vat la day sd tir -1 den + 1 . N i u gia tri N D V I cang cao thi khu vyc do CO do che phu thuc v&t tdt. Neu gia trj NDVI t h i p thi khu vyc do cd do che phu thip. Niu g i i tri N D V I am cho t h i y khu vyc khong c6 thyc vat. Chi sd SAVl d u g c x i c dinh theo cdng thiic dudi d i y :
SAVl = {{BandNiR- BandRed)/(BandNiR+
BandR^+L)}*(l+L)
Trong do: L = 0 khi khu vuc nghiln cuu co ty II thuc vat chiem da so, L = 0.5 khi khu vyc nghien ciiu cd ty II che phu bdi thuc vat va d i t t r i n g b i n g nhau, L -= 1 khi khu vyc nghiln ciiu cd ty 11 d i t trong chiem da so.
Trong nghien ciiu n i y , t i c gia lua chpn h i so L = 0 . 5 [ 2 ] .
Bang \. Di^ lieu dnh vien thdm PlanetScope duoc sic dung
M i anh Ngiy chup B6 p h i n giai (m) _Ngu^
la 20170529^024117_1038_3B_AnalyticMS lb 20170529_024147_101a_3B_AnalyticMS Ic 20170529_024146__l01a_3B_AnalyticMS 1 d 20!70529_024145_l 01 a_3B_AnalyticMS le 20170529_024ll7J038_3B_AnalyticMS 2 Ban d i hanh chinh
29/05/2017 29/05/2017 29/05/2017 29/05/2017 29/05/2017 2010
3 3 3 3 3 1:50000
CLS CLS CLS CLS CLS VDTOHR Nguon: hiips://www.planetcom/explorer
Nguyen Hai Hoa Tap chi KHOA HQC & C 6 N G N G H S 173(13): 2 5 - 3 0
Thu thap dfl' lieu
Dieu tra thyc dia Dit liSu inh PlanetScope
\
Xii ly anh *
Dit liSu GIS, so lieu Uiing k l
Phan loai anh bang chi so NDVI/SAVl
T
Danh gii do chinh xic phuong phip phan loai
i
n do lap phii ven bien nam 2017
Sa do 1. Quy trinh sd dung anh vien thdm PlanetScope thanh lap bdn do thdm phu K E T Q U A N G H I E N C U U
Phan loai anh bang chi so N D V I v a S A V l
K i t qua tinh toan chi sd thuc vat cac xa ven bien nam 2017 cho thay NDVI cd gia tri dao ddng tir -0,56 -5- 0,52, gia tri trung binh l i -0,17 va SAVl co g i i trj dao ddng tir 0,85 -^ -0,78, gia trj trung binh la -0,28. V d i gia t n trung binh chi sd thuc v i t am cho t h i y khu vuc nghien ciiu cd ty le dat t r i n g c h i i m n h i i u hon so vdi dipn tich d i t che phu bdi thyc vit. Ket q u i tinh toan chi so thyc v?t N D V I va SAVl d u g c t h i hien tai Hinh 2 va 3.
Hinh 2. Gid tri chi sdNDVI nam 2017 (PlanetScope Hinh 3. Gid tri chisd SA VInam 2017 (PlanetScope 29/05/2017) , 29/05/2017) fianb gia do chinh xac p h u o n g phap phan loai bang chi so N D V I va S A V l
K i t qua danh g i i dp chinh xac d u g c tdng hgp tai bang 2 va 3 . Qua b i n g 2 va 03 cho t h i y sy khac bi?t giiia k i t qua d i i u tra thyc dja bang GPS va k i t qua phan loai anh ddi vdi chi sd N D V I la 9 5 , 5 % va 9 7 , 1 % doi vdi SAVL
Nguyin Hai Hoa Tap chi KHOA HOC & CONG NGHE 173(13): 25-30 Bang 2. Ket qua phan ioai anh PlanetScope Iheo NDVI nam 2017
"^—^-^_GPS thin: dia
Anh phan ioai Thii^ v§t D^t trfing, d^t th6 cu- Nude ThucvSt 34 I 0 D^t tr6ng, dit did cu 1 34 0 Nuftc 0 I 19 T6nE
E>9 chinh xde (%) 94.3 97.1 95.0 95.5 Bdng 3. K^t tjuaphdn loai anh PlanetScope theo SA VI nam 2017
" ^ ~ - ^ - — ^ i i ^ t l n t c dia
Anh phan loaT Thi;%vat fiat trong, dat thS cir Nui^c Tlnicvat 34 1 0 Dat trSng, dat thd or 1 34 0 Nucfc 0 0 20 Tons
Do chinh x^e (%) 94.3 97.1 100 97.1 Bang 4. Dien tich tham phu theo chisd NDVI vd SA VI nam 2017
fi6i tu(me NDVI SAVl Dien tich (ha) TV ie (%) Di^n tich (ha)
Dat trong, dat tho cir 3728,9 33,8 4677,5 Thirc v?t 2054,4 18,6 2054,5 Niroc 5247,7 47,6 4299,0 T6ns 11030,0 100,0 11030,0
Ty le (%) 42,4 18,6 39,0 100,0
Dien tich tham phu xa ven bien kbu virc
nghien cuu
Nghien ciiu sir dung dir lieu inh PlanetScope nam 2017 (3 m x 3 m) dl xiy dung bin dd hiln trang tham phu t^i xa Da Lgc thuoc huyen Hlu Loc, xa Nga Tin vi Nga Thiiy thugc huy?n Nga Son tinh Thanh Hoa; xa Kim Dong thugc huyen Kim San tinh Ninh Binh bing chi sd thuc vat NDVI vi SAVL Ket qui xay dyng ban do hiln trang tham phii dugc the hiln t^i hinh 4 vi hinh 5.
phan chia vdi khoang gii tri chi so khac nhau, de tai kit hgp vdi ket qui dieu h-a ngoii thuc dia da tien hanh phan ra lam 3 Idp tham phti chinh cho khu vuc nghiln ciiu, bao gim dat tring va dit thi cu; Idp phu bdi thuc vat; va doi tugng la nude, dugc the hiln t^i hinh 4 va hinh 5. Kit qui dinh gia miic dg tin cay cua phuang phip phan loai rit cao, d6i vdi NDVI la 95,5% vi SAVl la 97,1%. Tir bin di hi|n trang thim phii, nghiln cuu udc tinh diln tich cho tirng doi tugng tham phii. Kit qui dugc t6ng hgp trong bang 4.
Hinh 4. Hifn trgng thdm phu xa ven bien tinh Thanh Hoa vd Ninh Binh bang chisd NDVI (PlanetScope
29/05/2017, dp chinh xac dat 95,5%) Ket qui tinh toin chi so NDVI vi SAVl dugc chia ra lam 30 Idp, trln ca sd cic Idp dugc
Hinh 5. Hien trgng thdm phu xa ven bien linh Thanh Hoa vd Ninh Binh bdng chi sd SA Vl (PlanetScope
29/05/2017, ddchinhxdcdgt97,i%)
Nguyin Hai Hoa Tap chi KHOA HQC & C 6 N G NGHE 173(13): 2 5 - 3 0 Ket qua tai bang 5 cho t h i y dien tich d i t che
phii bdi thyc vat dieo N D V I va SAVl gin n h u t u o n g dong (2054,0 ha), trong khi k i t q u i tfnh toan dien tich dat cho d i i tugng khac co su k h i c b i l t Idn n h u dien tich d i t trong v i d i t tho cu, 3728,9 ha theo N D V I va 4677,5 ha theo SAVL N g o i i ra, k i t q u i d i n h gia dd chinh xac ciia ban do p h i n loai cho thay SAVl cd ty II chinh x i c c h i i m d i n 9 7 . 1 % , cao h a n N D V I , d i l u nay cho t h i y sii dung chi so S A V l trong vi?c phan Ioai t h i m phu cho k i t qua t i t h a n N D V I [1], [2].
K E T L U A N
V i l e xay d u n g ban d o hien trang tham phu cac xa ven h i l n bang t u lilu anh PlanetScope nam 2017 thdng qua chi sd thuc vat cho dg chinh xac rat cao t r l n 95,0%., d i e biet phan loai tham phii b i n g chi sd S A V l (97,1%) cho dO chinh xac cao h a n N D V I (95,5%). Theo chi so SAVl, dien tich che phu bdi thuc v i t khu v y c nghien cuu la 2054,0 ha (chiem 18,6% tdng d i l n tich khu vyc nghien ciiu), d i l n tich d i t trong va dat tho c u chiem 4677,5 ha (42,4%.) va che phii bdi n u d e la 4299.0 ha (39,0%i). Ket q u i nghien ciiu la c a sd khoa tdt cho vi^c qui ho^ch phat trien qui dat khu vyc nghien ciiu.
Ltri c a m o n
Bai b i o da su dung t u lieu anh viln tham PlanetScope do CLS cung cap d e x a y dung ban do Idp phu. T i c gia xin chin thanh c i m an CLS da cung cap t u lieu v i y kien ddng gdp ciia c i c phan biin d l nang chat lugng bai bao.
TAI LIEU T H A M K H A O 1. Nguyen Hai H6a (2015), "Sir dung chi s i thyc vit NDVI d i phin loai va danh gia biin dfing Idp phO rirng nggp man tai huyen Tien Lang, Hai Ph6ng giai doiin 2000- 2013", Tap chi Khoa hgc vd Cdng ngh? Lam nghiep, so 11/2015, tr. 65-74.
2. Nguyen Hii Hoa (2016), "LTng dung anh viln thim Landsat v i cong nghe GIS trong xac dinh bien d^ng riing ng^p mjn ven bien thanh pho Hai Phong giai do^n 1990- 2014", Tgp chi Nong nghiip vd Phat trien Nong thon, so 3+4/2016, tr.
239-246.
3. Hoing Cong Tin, Ton Thit Phip, Nguyen Quang Tuan (2011), "iTng dung cong nghe vien thim vi h? thing thong tin dja ly (GIS) yong danh gii hiSn trang tham co bien d viing dat ngap nuac x i Huong Phong, huyen Huong Tra, tinh Thira ThiSn Hui", 77c Khoa hoc Dai hoc Hui. 65, pp.
231-239.
4. Hai- Hoa N., McAlpme C , Pullar D., Duke N.C., Johansen K. (2013), "The relationship of spatial-temporal changes in fringe mangrove extent and adjacent land-use: case study of Kien Giang coast, Vietnam", Ocean & Coastal Management. 76, pp. 12-22.
5. Mensah J. C. (2013), "Remote sensing application for mangrove mapping in the Ellembelle district in Ghana", Master thesis.
University Of Rhode Island, May 11, 2013.
6. Xu H. (2002), "Spatial expansion of urban/town in Fuqing and its driving force analysis".
Remote Sensing Technology and Appication, 17, pp. 86-92.
7. Ridd M. K. (1995), "Exploring a V-I-S (vegetation - impervious surface - soil) model for urban ecosystem analysis through remote sensing:
comparative anatomy for cities". International Jounal of Remote Sensing, 16, pp. 2165-2185.
8. Heute A. R. (1988), "A soil-adjusted vegetation index (SAVl)", Remote Sensing of Environment,
25, pp, 295-309.
Nguyen Hii Hda Tap chi KHOA HQC & CONG NGHE 173(13): 25 - 30
S U M M A R Y
USING P L A N E T S C O P E I M A G E T O C O N S T R U C T L A N D C O V E R IMAPS OF C O A S T A L V I L L A G E S IN T H A N H H O A A N D N I N H BENH P R O V I N C E S
Nguyen Hai Hoa*
Vietnam National University of Forestry The application of GIS technology and high resolution remote sensing data enables quick assessment of the status of coastal land cover with high accuracy. By using PlanetScope image (3mx3m) in 2017, the study has constructed maps of coastal land cover successfully with high accuracy of over 95.0%. In particular, the classification map by SAVl was assessed with 97.1% of accuracy, was higher than the NDVI (95.5%). As SAVl calculated in 2017, the area covered by vegetation was estimated at 2054.0 ha (18.6%), whereas bare land and residential areas were estimated at 4677.5 ha (42.4%) and areas covered by water was 4299.0 ha (39%). These provide a good basis for coastal land use planning in the study area.
Key words: Vegetation index, PlanetScope, land use, land cover, Thanh Hoa, NmhBinh.
Ngay nhan bdi: 25/8/2017; Ngay phdn bi?n: 07/9/2017; Ngay duyet dang: 31/10/2017 Tel- 0977 689948. Email hoanh@vfu edu.v.
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