31(3), 275-275 Tap chl C A C KHOA HOC VE T R A I OAT 9-2009
CAC MO HINH NGHIEN CLTU DINH LlTONG XOI MON DAT DO MUA vA KHA NANG AP DUNG
CHO CAC VUNG NHIET D 6 I AM
NGUYEN DINH KY, LUU THE ANH I. GlCil THIEU
Xdi mdn ddt do mua hidn dang la vdn dd cdp bach mang tinh toan cdu va nd tac ddng nghiem trgng ddn ndn kinh te' va mdi trudng sinh thai. Xdi mdn ddt tae dpng vd de dga xdu ddn cong tac quan ly bdn viing tai nguydn ddt, nang .sudt nOng nghiep va ehdt lugng mdi tmdng, dae biet la chdt lugng ddt va nude. Xdi mdn ddt la mdt qua trinh ty nhien nhung nhirng tae dpng deu cye va thidu kiem soat trong phat trien kinh td - xa hpi cila con ngudi da va dang lam gia tang qua trinh rira trdi, tinh nguy hai eiia xdi mdn. Trdn thuc td, tdng lugng ddt tdn thdt do xdi mdn phu thuPc vao eae ehi sd : 1) Chi sd xdi mdn cila mua, 2) Tham phil be mat, 3) Kha nang chd'ng xdi mdn cua ddt, 4) Didu kien dia hinh.
Trong cac chi .so uen, dia binh la mdt chi sd chinh anh hudng ddn xdi mdn ddt do mua ; nhirng khu vyc dia hinh dde rdt nhay cam vdi xdi mdn vi td'c do vd nang lugng ddng ehd'y mat trdn dia hinh dd'c thudng rdt Idn ; nhung nai ed mat dp ddng cha'y mat cao eung lam gia tang xdi mdn ddt.
Do vay, viec bao ve ddt khdi xdi mdn da trd thanh mpt vdn dd cdn thie't vd mang tinh cdp bach dd'i vdi cac nha quan ly, cac nhd lap kd hoach ; ddng thdi day la mdt ITnh vuc nghidn ciru, mdt bai toan thu hiit sy quan tam cila nhidu nhd khoa hgc, dae biet cdng tac nghidn eiru dinh lugng xdi mdn ddt thdng qua eae md hinh tinh toan, dy bao lugng ddt mdt di do xdi mdn. Tir cud'i nhung nam 1960 eua thd ky XX, cac nhd khoa hgc da nghien ciiu tdng hgp, phan tieh sd lidu thyc nghiem di xay dyng cac md hinh khae nhau phue vu eho cdng tac nghidn ciru dinh lugng xdi mdn ddt (cae md hinh dya tren thyc nghiem, md hinh vat ly va ly thuydt). Hien nay, vdi sy hd trg eila cdng nghe vidn tham vd he thdng tin dja ly (GIS), cac mO hinh nghidn cuu dinh lugng xdi mdn ddt eho kdt qua ed dd chinh xac cao, trong
thdi gian ngdn vd ed thd dp dung ddi vdi viing lanh thd rPng da dap irng duge yeu cdu cdp bach cua thyc tidn san xudt vd nghien cuu khoa hgc.
II. TONG QUAN c A c MO HINH DINH LUONG XOI MON DAT
Hien nay, uen thd gidi cd nhieu md hinh nghien curu dinh lugng xdi mdn ddt va duge ehia thdnh ba nhdm mdhinh chinh: l)Nhdm mdhinh thyc nghiem cd Phuang trinh mdt ddt phd dung (Universal Soil Loss Equation - USEE), Phuang trinh mdt ddt phd dung hieu chinh (Revised Universal Soil Loss Equation - RUSLE). 2) Nhdm md binb ban thyc nghiem cd Phuang trinh mdt ddt phd dung cai tidn (Modified Universal Soil Loss Equation - MUSLE) va Md hinh Morgan Morgan va Finney (MMF). 3) Nhdm md hinh dya tren cae qua trinh vat ly cd MO binb dy bao xdi mdn do mua (WEPP) va MO hinh xdi mdn dp dung eho viing lanh thd ciia Thomes (1985 va 1989).
Tae gia J.B. Thomes da xay dyng md hinh nghien curu dinh lugng xdi mdn ddt do mua dya tren cac qua trinh vat ly trong co chd xdi mdn ddt, md binh kdt hgp rinh toan kha nang van chuydn vat chdt va kha nang bao ve ddt khdi xdi mdn eila tham phil thyc vat thdng qua chi sd thyc vat chud'n NDVI (Normalized Difference Vegetation Index), phuang trinh tdng quat cila md hinh cd dang :
E = k*OF2*sl.67*e-0,07*v (1) trong dd : E - lugng ddt xdi mdn (mm/ngay hoae mm/thang, mm/nam phu thupe vdo bude thdi gian ciia md binh), k - chi sd xdi mdn ciia ddt, OF - ddng cha'y mat hinh thanh do nude mua (mm/dan vi thdi gian), s - dd dd'c (m/m) va v - dd ehe phil eila tham thyc vat (%).
Md hinh nay duge tae gia xay dyng vdi muc dich dp dung cho ty le nghien cHu cdp khu vyc (Regional Scale) va toan edu (Global Scale), bude thdi gian eila md binb phu thude hoan toan vao sd lieu quan trde vd lugng mua.
III. LTNG DUNG MO HINH XOI MON CUA J.B. THORNES CHO VUNG NUI CAO NHIET D61 A M HIMALAYA (AN D O ) Trong nghien ciiu nay, phuang trinh (1) duge diing dd tinh toan lugng ddt xdi mdn Uung binh ngay Uong ba thing mua mua (VII, VIII va IX) nam 2008 eho viing tmng tam cila ddy Himalaya (An Dp).
/. Gioi thieu chung ve khu vuc nghien cdu Khu vyc nghidn ciru d viing Uung tam eila ddy Hi- malaya (huyen Cbamoli, bang Uttarakhand, An Dd), thudc thugng ngudn cila sdng Ganga, tdng dien tieh ty nhien khoang 796.561 ha, dan sd 370.359 ngudi;
nam trong tga dd dia ly 29°45' ddn 31°00' vy dp Bac va 79°00' - 80°5' kinh dp DPng {hinh 1).
Dp cao tmng binh 629-7243 m so vdi myc nude bie'n trung binh ; dia hinh dd'c ddn rat dd'c, bi ehia
y^
^AC'
cdt manh va nghidng ddn tir bac xud'ng nam. Viing nghien eiru ed dae did'm khi hau nhiet ddi gid miia nui eao ; ehia ba miia ro ret, mua mua tap tmng tir thang VI ddn thang X (vdi 70 - 80 % tdng lugng mua ca nam), miia ddng bat ddu tir thang XI deh thang III nam sau va miia he tU thang IV ddn thang V.
Do ban chd vd didu kien dja binb nui cao va chia cat manh nen phugng thirc canh tac ndng nghiep trong viing hoan toan Id be thd'ng rudng bae thang.
Kdt qua xay dyng ban dd bien trang su dung ddt nam 2008 khu vyc nghien eiru bang tu lieu anh ve tinh IRS LISS-Ill cho thdy, bdng tuye't phil tren cac dinh nui cao phia bdc viing nghien ethi chiem dien tieh Idn nhdt (43,89 % tdng dien tich ty nhien khu vyc nghien eiru), tidp ddn la nui da 13,83 %, rirng ram chie'm 24,70 %, ddt ndng nghiep chidm 10,4 %, cay bui chie'm 6,78 %, edn lai la cae loai ddt khae.
2. DU lieu su dung va tinh toan cac thong sd dau vao cua mo hinh
a) So lieu ve tai nguyen da't va chl so xoi mon cCia dat (k)
Do khdng cd ban do ddt ty le ldn cila khu vyc nghien curu, nen ban dd dat ty le 1:500.000 do Co
quan Didu tra va Quy hoach Sir dung Ddt An Dp thanh lap nam 1999 theo he thd'ng phan loai dat cila My (Soil Taxo- nomy) da duge su dung eho nghien ciru nay. Chi sd xdi mdn cila ddt phu thupe chil ye'u vao ham lugng chdt hiru CO va thanh phdn eg gidi dat.
Tdng sd ed 10 phdu dien dat duge nghien ciru bd sung, cac mdu dat duge phan deh cac thanh phdn ly - hda hgc tai Phdng phan tich Ddt - Vien Vidn tham Qudc gia An Dp.
Kdt qua tinh toan chi sd xdi mdn cda dat trinh bdy trong bdng 1 va hinh 2, gia Ui cila k giao ddng tir 0,12 ddn 0,48.
b) Ban do do doc Ban dd dp doc duge xay dyng tir md hinh so dd eao SRTM (Shuttle Radar Topo- graphy Mission) cd dp phan giai 90 m. Tuy nhien, SRTM Hinh 7. So dd khu vyc nghien ciru
Bdng 1. Gia trj chi so xoi m6n cua da't va quy mo dien tich
STT 1 2 3 4 5 6 7 8 9 10 11
Gia tri k 0,12 0,14 0,24 0,27 0,340 0,375 0,380 0,410 0,420 0,480 Sdng bang
Tdng
Dien tich (ha) 208.285,92
40.430,88 44.327,52 276.449,76 44.163,36 8.019,36 36.650,88 3.335,04 17.229,60 23.034,24 94.634,44 796.561,00
Ty le (%) 26,15
5,08 5,56 34,71 5,54 1,01 4,60 0,42 2,16 2,89 11,88 100,00 DEM cd nhieu dien rich bi Idi, cae dien tieh ldi nay duge chinh sila dya Udn ban dd nen dja hinh ty le 1:50.000 va cae didm khdng chd mat ddt thu nhan duge uen thue dia bang may dinh vi ve tinh GPS.
Quy md dien tieh cila cae cdp dp dd'c khae nhau trong khu vyc nghidn ciru duge trinh bdy trong hdng 2 va hinh 3.
Bdng 2. Quy mo dien tfcti cua cac cap do doc khae nhau
STT 1 2 3 4 5 6 7 8 9
Gia tri dd dd'c (%) 0 - 1 1 - 3 3 - 5 5 - 10 10- 15 15-25 25-33 33-50
>50 Tong
Dien tieh (ha) 6.097,31 29.243,29 54.190,08 61.963,78 68.922,78 76.863,28 128.135,58 220.108,49 151.036,42 796.561,00
Tyle (%) 0,77 3,67 6,80 7,78 8,65 9,65 16,09 27,63 18,96 100,00
c) Chi so tham thi/c vat
Nhidu tac gia tren thd gidi da nghien ciiu va tim ra mdi quan be mat thidt giila tham thyc vat vdi gia Ui NDVI. Tu lieu anh vidn tham MODIS (Moderate Resolution Imaging Speetroradiometers thu duge tir ve tinh TERRA cd chu ky chup 16 ngay vdi dP phan giai mat ddt la 250 m duge diing dd tinh toan va thanh lap ban dd chi sd tham thyc vat cho khu vyc nghien ciru thdng qua cdng thiie :
0 5 10 20 km
Hinh 2. Ban dd chi so xdi mdn ciia ddt khu vyc nghien ciru
0 5 10 20 Km
V = 93,07466 * NDVI -i- 8,79815 (2)
Hinh 3. Ban dd dd dd'c khu vyc nghidn ciru Kdt qua tinh toan dp ehe phil tham thyc vat Uung binh thang VII giao dOng 0,00-97,99 %, thang VIII 0,00-100 % va thang IX til 0,00 % ddn 100 %.
d) Chl so dong chay mat hinh thanh do nude mua Ban dd mua trung binh ngay do Tmng tam Dy bao Thdi tie't An Dd xay dyng duge dung dd tinh toan ddng ehd'y mat binb thanh do nude mua. Db dm cila ddt Uude thdi did'm mua duge xem xet va dua vao Uong qua Uinh tinh toan vi dp dm ddt anh hudng rdt ldn de'n kha nang chira nude eiia ddt ; nd cQng anh hudng rdt ldn ddn sy hinh thanh ddng ehd'y mat khi mua xd'y ra. Ddng ehd'y mat chi hinh thanh khi lugng mua trung binh ngay ldn hgn dd trir dm eye dai cila ddt da bao hda. Kha nang giii nude mua cila ddt phu thudc loai tham thyc vat, loai ddt, ham lugng ehdt hiru eg, thanh phdn eg gidi cila ddt,...
Qua ke't qua tinh toan cho thdy, ddng ehd'y mat chl hinh thanh ndu lugng mua trung binh ngay ldn hgn 14 mm. Nhu vay, trong ba thing miia mua (VII, VII, IX), long sd cd 35 ngay vdi lugng mua Uung binh trdn 14 mm ; trong dd thing VII cd 15 ngay, thing VIII cd 10 ngay va thing IX cd 10 ngay mua.
IV. KET QUA VA THAO LUAN
Ddng ehd'y mat tmng binh ngay da duge tinh toan dd phue vu dy bio lugng ddt bj xdi mdn tmng binb ngay cila 35 ngay mua, sau dd ehia lugng mua Uung binb ngay thanh ba cdp de thuan tien cho cdng tic thd'ng ke va so sanh : lugng mua cao (>100 mm/ngay) cd 3 ngay, tmng binb (50-100 mm/ngay) cd 10 ngay va thdp (14-50 mm/ngay) cd 22 ngay.
Kdt qua tinh toin ddng ehd'y mat eiia nude mua cho thdy, ddng ehd'y mat eye dd'u chidm 18 % tdng lugng mua cua 35 ngdy mua nam 2008, ddng ehdy mat eye dai 97 % va ddng ehdy mat tmng binh 47 %.
Phugng trinh (1) diing dd tinh toin lugng ddt xdi mdn tmng binh ngay eho 35 ngay mua nam 2008 d viing tmng tam ddy Himalaya duge thd hien Uong bdng 3 va hinh 4. Don vi cila lugng dat bi xdi mdn la mm/ngay mua, vi vay ty trgng cua tdng da't mat da duge sir dung dd ehuydn ddi don vi tir mm/ngay sang tdn/ha/ngay.
Thdi gian Tu thing VII ddn IX, 2008
Bdng 3. Luong dat xoi m6n cua 35 ngay mua duoe chia theo 3 cap khae nhau
Tdng ngay Tdng lugng Lugng mua tmng binh ngay Lugng ddt xdi mdn (tan/ha)
mua mua (mm) Cdp Gid tri (mm) Max Min Mean
3 10
381 741
Cao Trung binh
> 100 50-100
924,078 1.404,420
0,0010 0,0029
5,514 28,956 Tdng
22 35
729 1851
Tha'p <50 50,699
2.379,197
0,0001 0,0040
9,540 44,010
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M
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^ O v e r l a n d f l o w (mm/35 rain days)
^Ig^ Hic^ : 1803. M
^ - - i , Low: 336.89
Dd'i vdi ba ngay cd lugng mua 127 mm/ngay (ngay 15, 22 va 23 thing 9 nam 2008), tdng lugng dat xdi mdn cye dai ghi nhan duge la 924,078 tdn/ha, tdng lugng ddt tdn thdt eye ddu la 0,001 tdn/ha va trung binh la 5,514 tdn/ha.
Ddi vdi 10 ngay cd lugng mua trung binb tir 14 de'n 50 mm/ngay (tdng lugng mua tugng irng 741 mm), tdng lugng ddt xdi mdn cye dai ghi nhan duge 1.404,42 ta'n/ha, tdng lugng ddt tdn thdt eye tidu 0,0029 tdn/ha va trung binb la 28,956 ta'n^a.
Dd'i vdi 22 ngay ed lugng mua trung binh tir 50 de'n 100 mm/ngay (tdng lugng mua tuang irng la 729 mm), tdng lugng ddt xdi mdn eye dai ghi nhan duge la 50,699 ta'n/ha, tdng lugng da't tdn thdt eye tie'u la 0,0001 td'n/ha va tmng binb la 9,54 tan^a.
•^ Hinh 4. Ban dd tong ddng ehd'y mat hinh thanh do nude mua eila 35 ngay vdi tong lugng mua
tugng irng 1.851 mm
Lugng ddt xdi mdn chia thanh 6 cdp tu rdt thdp ddn rdt eao theo thang sau : rdt thdp: < 5 tdn/ha/nam, thdp: 5-10 tah/ha/nam, tmng binh: 10-15 tdn/ha/nam, cao : 15-25 tdn/ha/nam, rdt cao : 25-50 tdn/ha/nam, nguy hidm : > 50 tdn/ha/nam.
Nhu vay, quy md didn rich cila cac cdp xdi mdn duge trinh bdy trong bdng 4 hinh 5, trong dd cdp nguy hidm chidm 15,22 % tdng dien rich nghien ciru, rdt cao 7,62 %, Cao 6,81 %, tmng binh 3,85 %, tha'p 4,81 % va rdt thdp 3,71 %.
Bdng 4. Quy mo dien tich cua li/dng da't bj xoi mon cho 35 ngay theo cac cap do khae nhau cua khu vUc
trung tam d l y Himalaya nam 2008
Ca'p xdi mdn Rdt thdp
Tha'p Tmng binh Cao Rdt eao Nguy hidm Bdng tuye't Nui dd Song, sudi
Tdng dien tich nghien curu
Dien tieh (ha) 29.520,00 38.317,12 30.693,12 54.218,56 60.728,61 121.236,48 349.593,70 110.172,61 2.080,80 796.561,00
Tyle (%) 3,71 4,81 3,85 6,81 7,62 15,22 43,89 13,83 0,26 100,00
KET LUAN
- Ke't qua nghien ciru irng dung md hinh xdi mdn da't cua J.B. Thomes eho quy mO viing lanh thd da dua ra mOt bure trang tdng quan vd xdi mdn ddt d viing nhiet ddi d'm niii cao nhu viing trung tam ddy Himalaya eiia Ai Dp. Md hinh xdi mdn ddt Thomes cho phep dnh toan tryc tidp va dy bdo lugng ddt bi xdi mdn tmng binh cho timg ngay mua (don vj tinh mm/ngay), cd thd tinh toin cho tung uan mua (dan vi tinh mm/tran mua). Vdi sy trg giiip cila tu lieu vidn tham vd cdng nghe GIS se rut ngdn thdi gian dnh todn va dd rang cap nhat sd lieu va tien Igi trong dieu chinh cde thdng sd ddu vao cila mO hinh.
- Ddi vdi viing nghidn cuu, kdt qua tinh todn ddng ehdy mat hinh thanh do nude mua eho thdy ddng ehdy mat chl duge hinh thanh khi lugng mua trung binh tren 14 mm/ngay. Kdt qua nghien curu cung xde dinh tdng sd cd 35 ngay mua trong nam 2008 cd lugng mua du ldn di hinh thanh ddng ehd'y mat.
- Kdt qua tinh toan tdng lugng ddt xdi mdn cho 35 ngay mua (thing VII cd 15 ngay, thang VIII cd 10 ngay va thing IX cd 10 ngay) trong mua mua nam 2008 cho thdy lugng ddt xdi mdn tmng binh la
Hinh 5. Ban dd phan cdp mure dp xdi mdn cho 35 ngdy mua eila khu vyc nghien curu
1,26 tdn/ha/ngay. Tdng lugng ddt xdi mdn cye dai trong 35 ngdy mua la 2.379 ta'n^a, eye tid'u la 0,004 tdn/ha va tmng binh la 44 ta'n/ha.
- d quy md viing lanh thd, mOt ban chd ddi vdi md hinh nay la eOng tac kidm nghiem kdt qua cila mO hinh vdi sd lieu quan trie tren thyc td, dd tu dd didu ehinh cic thdng sd ddu vao cila mO binb sao eho phil hgp vdi didu kidn thyc td. Qua trinh dnh toin Cling cho thdy, dd dd'c eila dia hinh, tham thue vat la cic chl sd nhay cam va anh hudng rdt ldn ddn qua Uinh xdi mdn ddt; ddng ehdy mat hinh thanh do nude mua la thdng sd khd tinh todn va phu thude vao nhidu ydu td nhu loai ddt, dp dm ddt, ham lugng miin, thdnh phdn ca gidi ddt va loai thyc vat.
- Nhu vay, md hinh nghidn curu xdi mdn ddt ip dung eho viing lanh thd eua J.B. Thomes (1985, 1989) hoan todn cd thd dp dung tinh toin vd dy bio lugng da't bi xdi mdn theo ngdy mua hoac tran mua eho cic viing nhiet ddi dm cd lugng mua Idn, tip tmng nhu Ai Dp, Viet Nam...
- Dd'i vdi didu kidn Viet Nam hien nay, ndu sii dung tu lieu anh MODIS NDVI dd phan giai 250 m chl phil hgp vdi quy md nghien ciiu cdp viing hoac toan qude (tuang iing vdi ty le ban dd 1/250.000
hoae nhd ban). Ndu mudn dp dung cho ty le nghien ciru ldn ban (1/50.000 hoac 1/100.000) thi phai .su dung cic tu lieu anh vd tinh cd dd phan giai ldn ban nhuu SPOT, ASTER,... Hien nay, tai Trung tam Vidn tham Qud'c gia thudng xuydn thu cic tu lieu anh SPOT, vi vay hoan toan cd thd ip dung md hinh Thomes dd nghidn ciiu d ty le ldn (cdp tinh, huyen) tu tu lieu anh ve tinh SPOT nay.
TAI LIEU DAN
[1] LUU THE ANH, 2008 : The Pilot Project of Postgraduate Diplome "soil erosion modeling for .soil eon.servation planning using remote sensing and geographic information system techniques - A case study in Cbamoli district, Uttarakhand state, India", CSSTEAP, Dehra Dun - India.
|2j A. KLIK et al, 1995 : Applicadon of WEPP billslope model on Austria. Proceedings of the 31"
Annual Conference of the American Water Resources Association (AWRA), "Water Management in urban areas". Houston, Texas, 313 - 322.
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Land degradation & development, 12, 579 - 539.
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Remote Sensing of Environment, 46,204-212.
[51 J.K. MITCHELL et al, 1980 : Soil loss esdma- don. In : M.J. Kirkby and R.P.C. Morgan, Soil Ero- sion. John Wiley and Sons Ltd., London. 17-62.
[6J R.P.C. MORGANetal, 1984: APredicrive Model for the Assessment of Soil Erosion Risk. Joumal Agricultural Enginee-ring Research 30, 245 - 253.
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[9] KG. RENARD et al, 1997 : Predicring soil erosion by water : A guide to conservation planning with the revised USEE, USDA Hand Book N". 703, USDA, Washington, D.C.
[10] J.J. STONE et al, 1995 : Hillslope surface hydrology. In USDA-Water Erosion Prediction Project (WEPP), Hillslope Profile and Watershed Model Documen-tation Technical Documentadon, NSERL Report 10, Flanagan DC, Nearing MA (eds) USDA-ARS National Soil Erosion Research Laboratory : West Lafayette, IN ; Chapter 4.
[Ill J.B. THORNES, 1985 : The ecology of ero- sion. Geography, 70, 222 - 234.
[12J J.B. THORNES, 1989 : Erosional equilibria under grazing, in J. Bindiff, D. Davidson and E.
Grant (eds). Conceptual Issues in Environmental Ar- chaeology (Edinburgh : University Press), 193- 210.
[13) R. WILLIAMS, 1975 : Sediment Yield Pre- diction with USEE using mn-off energy factor. In present and prospective technology for predicting sediment yields and sources, ARS-S-40, USDA, Washington D.C, 244 - 252.
[14] W.H. WISCHMEIER, et al 1958 : Rainfall energy and its relationship to soil loss. Transactions - American Geophysical Union 39, 285 - 291.
[15] W.H. WISCHMEIER & D.D. SMITH, 1978 : Predicting Rainfall Erosion Losses. Agricultural Handbook N". 537, USDA, Washington DC, USA.
S U M M A R Y
Overview of quantitative rainfall erosion models and its application to tropical monsoon regions The problem of land degradation by accelerated water-induced erosion is a serious environmental Issue for water and soil management in the world, particularly in tropical and subtropical regions where given the combination of medium textured soils, llthology, steep relief, seasonally concentrated rain- fall and abandonment of agricultural practices. As a consequence, there is a need for a better quantitative estimation of erosion processes on these landscapes for both on-site and off-site assessment of its Impact.
Much research has been conducted on the develop- ment of soil erosion assessment tools. In the last 60 years, a number of models have been built (empirical, conceptual or physically based) such as USLE, RUSLE, MUSLE, MMF, WEPP, LISEM.Thornes,...
In order to represent and to quantify the process of detachment transport and deposition of eroded soil with the aim of implementing assessment tools for either scientific or planning purposes. Physically based models are powerful modern tools to support such understanding.
This paper presents the results of demonstration soil erosion modeling at regional scale to estimate the average rate of soil loss using Regional Scale Model (Sheetwash Erosion Model of Thornes, 1985, 1989) with assistance of Remote Sensing and GIS technology in the part of the centre of Himalayan mountain range.
Ngdy nhdn bdi : 13-01-2009 Vien Dia ly
(Vien Khoa hgc vd Cong nghe Viet Nam)