Tir DONG HOA CAC BlTOC PHAN XfCH KHONG GIAN TRONG PHAN YUNG 6 NHIEM VUNG NlT^C VEN B 6 HAI PHONG B A N G G I S Nguygn Thi Thu Ha, Tran Dinh Lan Vieri Tai nguyen va Moi truong Bien 246
Trang 1Tir DONG HOA CAC BlTOC PHAN XfCH KHONG GIAN TRONG PHAN YUNG 6 NHIEM VUNG NlT^C VEN B 6 HAI PHONG
B A N G G I S
Nguygn Thi Thu Ha, Tran Dinh Lan
Vieri Tai nguyen va Moi truong Bien
246 Da Ning, Hai Phong Email: hanttfgtimer.ac.vn
Tom tat
Viec nghien cuu Ictp trinh phdt trien chuc nang ma rgng trong cdc phan mSm cintyen ngdnh nhc'tm tgo ra cong cu ung dung theo cdc muc dich su dung khdc nliau la rat can Ihiel Phan mem Arcview 3.2 cd md nguon md cho phep nguai sit dung lap trinh them cdc chuc nang phan tich khong gian bang ngon ngu lap Irinh mo rang Avenue
Bdo cdo nciy trinh bdy viec su dung dgc diem do de tu ddng hoa cdc buac phan tich khong gian nham phan vimg d nhiem chat huu ca de phan hiiy tai vimg nuac bien ven ba Hai Phong, dua ra mot bice Iranh tong the ve hien trgng moi truang nuoc hien ven ba cua thanh pho, phan dnh cdc nguy co tiem dn gay
d nhiem moi truang fir cdc nguon thdi vd cdc hogt dong kinh te xd hoi
Abstract
AUTOMATION OF SPATIAL ANALYSIS STEPS IN POLLUTION ZONING OF HAI •
PHONG COASTAL WATER AREA BY GIS
The research on programming to develop the extended functions of the
specialized software to create tools for different applications is essential The open source software ArcView 3.2 allows users to program additional spatial analysis functions using the Avenue language
In this article, the programming on automatic spatial analysis is presented
It lielps to develop zoning scheme for tfw easy degradable organic substances
in Hai Phong coastal water, to provide a comprehensive picture of the city's coastal water environmental status, which reflects the potential risks of
environmental pollution from the waste sources and the socio-economic
activities
\ MO DAU
Hai Phong la thanh pho co nen kinh te soi dgng, dien ra nhieu boat dgng t£ii vung ven bien nhu: cong nghiep, nuoi tr6ng thuy san, hang hai, ; dieu nay lam cho vimg nuoc ven
Trang 20 nhiem va phan vung 6 nhiem ciia moi truang nuoc ven bo Hai Phong la cong viec rit cin
thiet Co so du lieu GIS voi kha nang luu trG, tim kiem, phan tich va hiln thi thong tin dia
ly la mgt cong cu manh trong quan ly va giam sat sy phan b6, danh gia chat lugng nuac bien, du bao nguy co 6 nhiem Phan mem Arcview 3.2 la mgt phan mSm thuong mai ciia Vien nghien cim cac he thong moi truang (ERIS), My, ap dung cong nghe he thdng thong tin dia ly (GIS) Tuy nhien viec su dung toi da kha nang cho phep co sin trong phin m^m Arcview 3.2 de phan tich kliong gian, chong lap ban do phai ap dyng qua nhi§u buoc tinh toan va nhieu thao tac khac nhau
Dai viet nay trinh bay mgt chuang trinh dugc lap trinh trong ngon ngu Avenue cua phan mem Arcview GIS [1-8], nham xay dyng them mgt chuc nang moi trong phan tich khong gian, ty dgng hoa cac buoc tinh toan, chong lap ban do c6 trgng so, dua ra ket qua hien thi duoi dang ban do mgt each nhanh nhat va chinh xac nhit dg phan viing 6 nhiem moi truong viing nuoc bien ven bo Hai Phong
II PHl/ONG PHAP
- Phuong phap xay dung cffso' dG lieu
Ban do dia hinh khu vuc nghien cuu, cac lop thong tin vh bo bidn, song, duong dugc so
hoa va luu tru duoi dang so, sir dung cho viec phan tich khong gian
Cac tram khao sat dugc nhap vao bang dG lieu su dyng phan mem Microsoft Access Cac diem khao sat hien thi duoi dang diem, tga do dugc dua vao bang thugc tinh trong Arcview bang viec su dung chuc nang ket noi SQL Cac tram khao sat se dugc hien thi tren ban do nen theo diing vi tri tga do
- Phuong phap ngi suy
Phuang phap ngi suy trgng s6 nghjch (IDW): cho rang gia tri tai mgt vi tri khong lay mau la trung binh trgng so theo khoang each ciia cac gia tri tai cac vi tri lay mau Cac diem gan vi tri can ngi suy hon se co anh huong Ion ban tai gia tri ngi suy so voi cac diem 6 xa hon Nhu vay, vi tri ngi suy cang gin vai dilm khao sat thi gia tri ngi suy cang gan voi gia tri do dugc tai diem khao sat Gia su co i diem xung quanh diem can ngi suy, ve mgt
duong tron co tam tai dikm ngi suy, ban kinh dmax sao cho tat ca cac diem xung quanh diem
can ngi suy nim trong pham vi ciia duong tron, khi do gia tri cua diem can dugc ngi suy dugc tinh theo cong thuc sau:
Trong do z,: la gia tri do dugc tai cac diem quan trac
W,: ty trgng dugc tinh theo cong thiic sau
Wi = 1 - di/dmas diem gan nhat co anh huong nho
Wj = 1- (di/dniax)^ diem gin nhit co anh huong trung binh
Trang 3- Phuong phap chong lop du lieu c6 trong s6
Sau khi nhap cac lop tliong tin dau vao, phan tich khong gian thu dugc cac lop tliong
tin chuyen dh duoi dang luoi; cac lop thong tin nay dugc tinh toan, sau do chong lop co trgngj
s6 ^ '^ Ch6ng lap ban d6 dh tao ra mgt ban do moi ma tren do gia tri dugc gan cho m6i dignfi
hoac nhom diSm la mgt ham cua cac gia tri dgc lap lien quan den timg vi tri cua cac lop^
thong tin dugc chong
Giasuco n lopco gia trj la PI, P2 Pn Chfing n lap co trgng so theo c6ng thGc sau:
P= W1.P1+ W2.P2+ Wn Pn
Trong do W1+ W2+ Wn= 1
- Phuong phap lap trinh trong ng6n ngu Avenue
Avenue la ngon ngu lap trinh su dyng de phat trien ung dung trong phan mem Arcview
3.2 Trong Arcview co nhi6u doan code mlu ma co the su dung de truy c^p nhtrng chirc
nang khong co gia tri qua giao dien binh thuong cua Arcview Ngon ngG Avenue lien quan
chat die voi phin mim Arcview va ngudi su dung co the thao tac tren Arcview de thay doi
each lam viec trong Arcview hay de thuc hien nhGng cong viec cu the nao do, tham chi co
the phat trien ung dung theo giao dien do hga trong Arcview
Avenue la ngon ngG lap- trinh huong doi tugng; no cho phep chiing ta kliai thac
ArcviewGIS thong qua he thong cac doi tugng dugc thiet ke san mgt each chi tiet (View,
theme ) He thong cac doi tugng nay dugc to chirc kha ro rang va de hieu trong moi
truang Arcview, cung cap day du cong cu de nguai diing co the de dang lam viec voi
Avenue Co the tao dugc cac bieu tugng do hga trong giao dien, thiet lap thugc tinh cua
bieu tugng do de dieu khien chiing; co the viet nhung doan code trong Avenue de thyc
hien lenh tuong ung voi cac nut trong cua so giao dien do
Viet doan code
Bien soan
Chay va ket noi script
Tao nut trong giao
Trang 4Hinh 1: Sa do cdc buac lap trinh trong phan mem Arcview 3.2
it (ChDCridLi
B i n
.thoGrid -O.i
GelActiveDoc
theVieu GetTb
C Count <-l)
Grid
il (IheGridList Gelfitl IsV
than
theGridl • cheGndList
labela - < -TCCp-.-Trn
defaults { ".—i
ordBT - HsgBoic Hultiln
vhile ( rdor count • 0
-^
Ge
le-TRUE)
U)-GetHd
•Layer •«< AsString, lebels d e i a u U s )
order"- BsgBoii Multiinput(thBGridl "leyor "+x.AsString, IsbDls defaults )
TCCP - ordor GBt(O)-AsHujibor
TrongSo - order Get(ll AsBiibor
t b o G n d - thaGrid * theGridList Get[jr) GBtGrid •> TioagSo ^ TCCP
Hinh 2: Bien dich script trong phan mem Arcview 3.2
Trang 5So lieu phan bo
ham lirgng chat 1
So lieu phan bo ham lu-gng ch^t 2
So lieu phan b6 ham lirgng chat
So lieu phSn bo ham lugng chat n
CSDL GIS
Ban do phan bo
ham lugng chat 1
Noi suy
Ban do phan bo
ham lugng chat 2
H€ so rui ro
' RQi
Ban do phan bo ham luong chat
He s6 rui ro
' RQ2
Ban do phSn b6 ham Ivongchitn
He so rui ro RQ
H€ so rui ro
• R Q H I
Chong lop
CO trong so
Ban do mu'c do rui ro
0 nhiem
Hinh 3: Sa do cdc buac thuc hien md hinh t\c ddng hoa
III KET QUA VA THAO LUAN
Co the ap dyng cac phuang phap tren cho nhieu thSng so^ khac nhau tai mgt vung
Trang 6BOD va COD cua viing nu6c bi^n ven b o Hai Phong voi s6 li6u khao sat mua kh6, t i n g
m^t, nam 2 0 0 9 1 ^ 47 tram Vi s6 tram khao sat phan bo khong deu, nen da &ix dung duong
bd biSn 1 ^ gioi han bien cho viec ngi suy YM qua thu dugc la cac lop thong tin ve phan
bo ham lugng BOD va D O trong vimg n u a c bien ven b o k i u vyc Hai Phong mua kh6 nam
2009 Tu cdc lap thong tin nay, da tinh toan h e so rui ro cua thfing s6 BOD, DO cua tung khu vyc theo cong thfic:
RBOD= H a m l u g n g B O D / T C C P B O D
RcoD= H ^ lugng D O / T C C P D O Trong d6: TCCP: tigu chuin cho phep B O D va DO
M i l
1 1
CD
• •
L J
C H O G I A I RS't an todn
An todn Nguy CO
a nhi§m Ngodi viing nghiSn
Hinh 4: Ban do phan viing muc do d nhiem chat hihi co de phan hiiy
Trang 7Coi thong s6 BOD va COD la cac thong so chi thi cho miic d6 6 nhiSm chit huu co
dl phan buy, sau khi tham khao chuyen gia ve vi?c cho diem muc do bi§u thi 6 nhiem cua cac chit biin co dl phan hGy, da tinh dugc trgng so cua cac thong BOD va DO tuong ung
la 0.7 va 0.3
Sau do, da tiln hanh ch6ng lop co trgng s6 2 lop thdng tin he s6 rui ro ciia 2 th6ng s6" BOD va DO, chia trung binh co ket qua cuoi cling va nhan dugc lap thong tin ve t^ng h^ s6 rui ciia su 6 nhilm chit huu co cua timg khu vyc MGc nil ro dugc phSn thanh 4 cdp nhu thi hien trong ban d6 hinh 4 Nhiing vung c6 h? so rui ro <5: 1^ vimg an toan, 0.5-0.75: vimg c6 rui ro 6 nhiem chat hiiu co de phan hiiy, 0.75- I: viing co rui ro cao va >I: la nhGng viing da 6 nhiem chit hihi co de phan hiiy Ket qua cho thSy, khu vyc 6 nhiem va e6 muc do nii ro cao nhat la cua song Cam, Dinh Vu, khu vuc gan D6 Son va khu vuc song Bach Dang
Toan bg qua trinh tinh toan va chong lop c6 trgng so dugc ty dgng hoa thong qua 1 lenh moi, dugc lap tririh trong giao dien cua Arcview 3.2 Sau khi co dugc 2 lop thong tin
da ngi suy cua BOD va DO, ta co ngay dugc ket qua cuoi cimg Chi can an vao bieu tugng moi da dugc tao ra trong giao dien hoac vao menu va chgn lenh, may tinh se hien len ciia s6 dl dilri cac gia tri vl TCCP, trgng so ciia thong so trong timg lop thong tin May tinh se
tu dgng tinh toan be so rui ro cua timg 16p thong tin, cgng chong lop co trgng s6, sau do lay trung binh lop-thong tin ve tong he so rui cua sy 6 nhilm chat hGu co cua timg khu vuc Can luu y la, nlu s6 lieu day du hon va so tram khao sat phan bo dong deu hon trong pham vi nghien cuu thi ket qua phan vung 6 nhilm chSt hihi co de phSn hGy se chinh xac hon Viec lap trinh co the ket noi, mo rgng vol ngon ngu khac va phat trien cho cdc img dyng khac nhau
IV KET LUAN
Cong cu ma rgng trong phan mem Arcview GIS nham tu dgng boa cdc budc phan tich khong gian trong truong hgp tinh toan va cgng chong lop vol cac lop thong tin da dugc lap trinh giiip nguoi sG dung giam di cdc buoc thyc hiSn theo cdch thu cong, N6u nhu thao tac thu cong phai trai qua nhieu buoc tinh toan, thi vcd thanh c6ng cy ty dgng hoa d5 dugc lap trinh, chi can nhap thong so dau vao la cdc lop thfing tin co the ty dgng dua ra ket qua cuoi cimg
Viec ap dyng qua trinh ty dgng noi tren cho 2 chit 6 nhilm hGu co de phdn hiiy la
BOp va COD tai vung nuoc bien ven bo Hai Phong da chi ra viing co nil ro 6 nhiem cao
nhat la khu vyc cua song Cim, Dinh Vu, gin D6 Son, song Bach Ding Khu vuc nu6c cita song Van Uc va viing nuac bien cang ra xa ba chit 6 nhiem hihi co dl phdn buy vin & nguong an toan
Trang 8TAI LIEU THAM KHAO
1 Amir H Hazavi "ArcView GIS/Avenue developer's guide "
2 'E^^." Using Avenue, customization and Application Development for ArcView GIS"
3 ESRI "Arcview Spatial Analyst, advanced Spatial Analysis Using Raster and Vector Data"
4 Guide of ITS Durham University "Programming in Arcview 3.x GIS using Avenue'"
5 D6 Thu Huong, 2003 "Tiep can mo hinh GIS ddnh gia nguy co 6 nhiim ddu trong nude vinh Hg Long "
6 Shunji Murai, 1999 "Gis work book-foundamental Course and Technical Course, Japan Association of Surveyors Public "
7 Le DGc Tri, Tran Van Phdp- "Lap trinh GIS can bdn "
8 University of South Carolina "Avenue Part 11: Getting Results Training document"
Ngu'd'i dgc nhan xet: TS Nguyen Minh Son