I KHOA HOC i p J . I J I J J M ' l : ^
XOI MON BE MAT VA VAN CHUYEN BUN CAT TRONG LUtJ v i r c SONG L 6
Le Thanh Hiing Trudng Dgi hgc Thiiy Lgi
Tom tat: Bdi bdo ndy di cap vdn di xoi mdn bi mat vd van chuyin biin cdt trong luu vuc song Ld, tir do lam ea sd du bdo dnh hudng ciia su thay doi thdm phd vd xdy dung hd chiia din xdi mdn bi mat vd vdn chuyin biin cdt luu vuc. Phuang trinh mdt ddt phd dung hiiu chinh (RUSLE), md hinh tap trung ddng chdy, thay ddi sic dung ddt, dnh hudng cua hd chiia da dugc sii dung di tinh todn trong md hinh xoi mdn vd van chuyin biin cdt trong diiu kien tu nhiin vd diiu kien thciy ddi thdm phit. Thay ddi tinh hinh sit dyng ddt, khodng 20% diin tich rimg chuyin ddi thdnh ddt ndng nghiep vd 15% biin thdnh ddng cd vd doi troc, lugng biin cdt van chuyin trong sdng tdng 28%. Hd chira Thdc Bd vd ho chua Tuyen Quang sau khi dua vdo khai thdc dd lam thay ddi hdm lugng biin cdt ddng chdy tit 1971 vd 2005. Phdn tich ede sd lieu quan trde vi hdm lugng bim cdt, gidm khodng 95% lugng biin cdt van chuyin trong sdng Chdy do tdc dong cua hd Thdc Bd vd gidm khodng 71 % trong sdng Gdm do tdc dong cua hd Tuyen Quang.
TuKhda: Hd chira, luu vuc song Lo, RUSLE, van chuyen biin cdt, xoi mdn be mat
Summary: This article approaches the problem of surface erosion and sediment load in the Lo river basin, in order to predict the possible impact of reservoirs and land use changes on surface erosion and sediment load in the river basin. The Revised Universal Soil Loss Equation (RUSLE), a river network routing scheme, land use change and effeets-gf reservoirs were accounted in modeling erosion and sediment yield passing from natural impounded and land use change conditions. Land use changes scenarios, parameterized on the basis of observed land use changes in the impounded basin, assuming that 20% of forest area is converted into rice and agricultural crops and 15% into bushes, shrubs and meadows show that a 28% increase of sediment load can be expected. The Thac Ba reservoir and the Tuyen Quang reservoir already changed sediment concentration since 1971 and 2005 when they were, respectively, in operations. By analyzing the sediment concentration data, the sediment load reduction of about 95% is shown for the dam in the Chay river (Thac Ba reservoir) and 71% is for the dam in the Gam river (Tuyen Quang reservoir).
Keywords: Reservoirs, Lo river basin, RUSLE, sediment load, surface erosion
1. MOf D A U thirc vat tren b6 mSt luu v\rc. Bfin canh do tren Khu vuc nghien cuu la Imi vuc song Lo co ' ™ ^ ^ <^ "f f '^'>*' ' * " '^ '^'^ " 4 (dmg dien tich 38165 km^ (tai Viet Tri), noi co tmh ^ ^ 2.«-10 m ) va Tuyen Quang (dung tich trang phat rimg lam nuong ray manh me ciing 2,245-10 m ) dugc dua vao khai thac lan lupt voi tap tuc canh t i c lam thay dfli thim phu <« " ^ ' ^ ^ l ™ °5m 2005 da lim thay doi co ban ham luang bun cat ti^ nhiSn trong song.
Cae thay doi do tac dong khong nho den sv x6i Ngay nh§n bai: 02/6/2017 UJ5JJ jjg ^j^j J^J^ y^^ y^ ygjj chuyen biin eat Ngay th6ng qua phan bien: 12/7/2017 ^ ,
N ^ y duyet dang: 26/7/2017 """"^ '™2-
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Bai bao nay de cap den van de xoi mon be mat luu vuc theo thai gian va v§n chuyen bim cat trong luu vuc song tu do du doan anh huong ciia sir thay doi tham phii thuc vat, xay dung ho chiia va cae yeu to khac bao gom ca cae yeu to tu nhien va tac dong cua con nguai gSy ra d6i vai luang xoi mon va van chuyen bun cat trong luu virc song Lo.
2. Liru VXrC NGHlfiN CUtJ
Vung ngbiSn curu la km vuc song Lo, mot trong ba nhanh chinh cua song H6ng. Song Lo duac hpp thanh voi song Gam va s6ng Chay; co do d6c tnmg bmh lim vuc la 19,7%; co dien tich luu vuc la 38165 km^ (tinh d8n Viet Tri) trong do 22629 km^ tren lanh thd Vi^t Nam; chieu dai dong chinh la 470 km (275 km a Viet Nam); do cao frung binh lim vuc la 884 m, phSn cao tren 250 m chi6m ban 80% tong dien tieh km vuc (binh 1).
Hinh 1: Bdn do luu vuc sdng L6 (Trung Qu6c vd Viet Nam)
3 . L U ' 0 N G M U ' A , D 6 N G C H A Y V A B U N C A T dao dpng trong khoang 1500-1800 mm, dac 3.1. Che d9 mira bi6t 6 tram BSc Quang len tai 4814,8 mm.
T, . L. L - . , -T. . Trung bmh hang nam s6 ngay mua la 150 Luang mua trung binh nam tinh Tuyen Quang
98 TAP CHf KHOA HOC VA C O N G NGHf THUY LOl S(5 39 - 2017
KHOAHtJC ^ . J . I J I c U l e t ! ! : ^ ngay. Miia mua trung voi mua he vol tSng
luong mua ca mua khoang 1310+2131 mm (tai cic tram khac nhau), chiem 85,3*94,1% t6ng luong mua hang nam. Mua kho trimg vol mua dong, CO t6ng lugng mua c i miia la 134^225 mm, chi chi6m 5,9+24,7% tdng luong mua
hang nam. Cae thing co luong mua Ion la thing 7, thing 8 va thing 9 voi khoang 250+320 mm/thang, va dac biet len den 950 mm/thang (thing 9 nam 2000 t^ TP. Tuyen Quang). Clii tiet luong mua trung binh thing t ^ cic tram d o t r e n l u u v u c g h i d bang 1.
Bang 1: L i r ^ g mu^ trung binh t h i n g , nam tai cae tram tren luu vi^c song Lo Bon vi.mm Thdng
BaoMc Bao Lac luc Yen PhoBdng M Khirtmg RSafhi Bdc Me Bdc Ha Bdc Quang ChatRa NaHang Pho Rang ChgrBSn Chiem Hoa Hdm Yen Tuyen Quang ThdcBa Vii Qutmg Phi Ho Viet Tri
1 39,0 22,2 32,5 20,2 41,7 17,8 26,0 24,1 72,0 19,0 21,2 27,4 17,4 26,0 27,3 23,1 21,9 31,9 33,7 26,4
2 43,7 25,9 41,9 19,9 46,1 21,6 27,6 31,8 73,5 22,4 29,5 34,8 27,2 32,8 39,5 29,5 30,2 38,8 37,1 30,9 i 67,6 44,9 71,7 38,0 50,2 44,7 51,1 57,1 90,3 45,0 56,7 59,6 46,5 52,9 56,2 52,4 54,6 57,8 55,0 46,2
4 108,6
76,1 136,4 94,7 115,6 88,4 90,1 124,8 246,3 92,8 107,5 135,3 112,6 122,9 126,4 112,8 112,7 111,3 112,1 102,3
5 305,0 165,1 209,0 181,0 204,5 196,0 244,3 194,9 761,9 176,0 251,9 183,6 203,5 234,4 232,1 222,6 212,4 209,9 215,2 187,2
6 450,8 212,7 283,5 313,1 327,2 294,2 287,7 237,5 983,7 238,7 322,4 213,8 320,9 280,4 281,6 270,8 255,1 243,7 247,9 260,6
7 545,8 241,6 328,0 367,1 405,2 338,5 329,2 276,2 919,4 254,0 336,0 251,1 345,8 283,9 321,6 289,6 331,8 281,4 279,3 269,4
S 415,2 217,3 396,6 323,6 363,0 319,9 267,0 332,2 625,1 239,7 278,4 333,0 340,9 295,3 318,3 298,4 332,2 275,1 286,7 272,2
9 234,5
98,2 255,1 180,7 207,5 165,2 132,6 211,1 406,5 125,1 135,3 203,8 162,8 166,9 184,7 172,6 198,4 195,1 202,5 183,0
U 165,9
76,3 144,4 123,4 159,5 105,0 91,6 124,8 391,6 86,2 90,2 112,9 119,3 106,9 120,8 124,3 126,7 136,7 151,3 142,0
;/
83,8 41,5 59,7 66,6 81,5 52,4 46,6 64,1 166,1 40,8 43,4 44,8 44,8 45,3 44,7 45,6 50,8 48,0 60,4 51,8
12 34,5 21,5 27,6 26,5 35,4 21,1 21,6 22,3 78,3 19,2 22,7 17,4 20,6 22,0 22,2 17,3 20,5 24,0 24,0 20,2
Ndm 2494,4 1243,4 1986,3 1754,7 2037,4 1664,6 1615,4 1700,1 '4814,8
1358,9 1695,2 1617,2 1762,4 1669,7 1775,4 1659,0 1747,3 1653,6 1705,3 1592,3
3.2. Dong chay va biin cat
Cae s6 lieu dong chay va ham lupng biin cat la lijmg trong song duac quan trac, do dac tai 8 ti^m thuy van khac nhau b6 tri trong liru vuc song Lo g6m: tram Bao Yen, tram Thac Ba, tram Ha Giang, tram Ham YSn, tram Bao Lac, tram Chiem Hoa, tram Tuyen Quang va tram Vu Quang.
Tir hinh 2 cho thay, sau khi ho chua Thac Bk di vao v ^ hanh (nam 1971) ham lupng biin cat la lOmg trong dong chay do duac tai ha luu giam dot bi6n. Ham luong bun cat la limg trung binh trong giai doan 1971-1975 giam xuong con 0,026 kg/m^ so voi miic trung binh 0,529 kg/m^ trong giai dogn 1959-1970 (hiroc khi xay dung h6 chiia), ty le ling dpng bim cat trong long h6 Thac Ba dat 95%.
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Hinh 2: Anh hudng ciia hd chita Thdc Bd den luang biin cdt lo lung
d tram Chiem Hoa (ha luu h6 Tuyen Quang), giai doan 1965-2004 (tru6c khi xay dung ho ham luang bun cat la liing trung bhih do dupe chiia) la 0,436 kg/m^, hieu qua lang dpng la trong giai doan 2005-2007 la 0,184 kg/m^ va 71% duac tb6 hien a hmh 3.
Dong chay va bhn cat tai tram Chiem Hoa
Iz^iidur J
Nam 2004, ho Tuyen Quang dira vao khai thdc
'-'\r^K
^if-M-'W
•i '• ' i y
Sir suy gidm ham lugng biin cdi lo lung
Irong ddng chdy
1 9 ^ 1S80 1965
• • I C3E->CD Z£G 2010
Hinh 3 • Anh hudng cua hd chira Tuyen Quang din lugng biin cdt lo lung Nhung s6 lieu nay phu hap voi nhiing s6 lieu cua Le Thj Phuang Quynh va nnc [I].
4. MO HINH RUSLE VA M 6 HINH T^P TRUNG DONG CHAY
100 TAP CHl KHOA HOC VA C O N G N G H E THUY LOI S(5 39 - 2017
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4.1. Mo hinh RUSLE
Phuong trinh mdt ddt pb6 dung (USLE), Wischmeier va Smith [2], va phien ban hieu chmh (RUSLE), Renard va nnc [3], dupe iing dung de ti'nh toan luong xoi mon b6 mat trung bmh hang nSra, mo hinh RUSLE dupe lap trinh bang ngon ngu FORTRAN, Le Thanh Hiing [4]. Phuong trinh USLE/RUSLE thuang dupe bieu dien theo cong thiic:
A = R-K-LSCP trong do:
- A la ton that dat trung binh tren mot hecta trong mpt nam (tdn/ha.nam)
R la he s6 kha nSng xoi mon do mua (MJ/ba)-(mm/h)
6 day, tac gia sii dung phuang trinh eiia Loureiro vaCoutinho [5]:
I N 12
^=-f^J2 I^C^OS • rain,o - 8 8 . 9 2 • days.oj^j
^ i - l m - l
trong do: N la so nam quan trie; rainio la lupng mua hang nam > 10 mm; dayjo la s6 ngay co lupng mua hang nam > 10 mm. Sii dung phuang trinh tren, tinh toan gia tri he s6 R tnmg binh hang thang cua luu vuc song L6.
K la he so xoi mon d l t trung binh (tdn/MJ)(h/mm). CJ day, chpn K = 0,022 dua tren cae nghien ciiu cua Vezina va nnc [6];
Pham Hung [7]. Gia tri K nhu tren ciing phu hop voi nghien ciiu cua Zhang va nnc [8].
- LS la chieu dai va dp doc ciia suon doc. Trong ngbien ciiu nay, sii dung cong thiic cua Moore va Burch [9] de tinh toan he so LS nhu sau:
LS
_(A^ r (smp Y '1,22,0 lo,0896j
trong do: As dien tich 6 thOra canh tac tren mpt don vi chiSu rpng suon doc, vai vimg nui phia bdc Viet Nan, chpn dem vi chiSu rpng suon ddc la 22,1; m', n' la cae he s6 tuang iing chpn la 0,6 va 1,3; p la goc nghieng suon d6c so vcri phuang ngang.
- C la he so su dung dat, C < I, vcd d6i hoang boa C = 1, He so C ciia luu vuc song Lo d6i vai tung loai cay trong dupe thS bien trong bang 2, theo Vezina va nnc [6], va trong bang 3, theo Pham Hung [7].
Bang 2: He so C, theo Vezina va nnc [6]
Loai canh tdc Lua(2vu) Liia (1 vu) Liia (1 vu) voi ngo
San Ngo Daunanh
HesdC 0,55 0,40 0,55 0,22 0,12 0,28 Bang 3: Hf so C, theo Phjim Hiing [7]
Logi canh tdc Liia va hoa mau Cay bui, doi co Rimg tir nhien Dat hoang, doi hoang
H$s6C 0,60 0,18 0,003 1,00 - P la he so giai phap bao ve dat, P < 1, khi khong CO giai phap bao ve ddt P = 1. Vai hinh thiic canh tac pho bien trong liru virc song Lo la rupng bac thang, dua theo nghien ciiu ciia Vezina va nnc [6] va Pham Himg [7], trong nghien ciiu nay, lua chpn he so P = 0,2.
4.2. Mo hinh tap trung dong chay P I M O S H O N G )
Dong chay cua biin eat xoi mon do mua tren cae suon doe eiia luu vuc dupe chuyen qua mo hinh tap trung dong chay mang luai song. Mo hinh ciing dupe lap trinh bang ngon ngQ FORTRAN, Le Thanh Himg [4], dira han thuat loan dp doc 8 huong, Ranzi va nnc [10]
di tinh toan lupng dong chay biin cat a trong mang ludi song Lo.
5, KET QUA DAT DU'OC 5.7. Ve xoi mon ddt be mgt
Mo hinh RUSLE da duac ap dung tinh toan cho Iim vuc song Lo bdng each sir dung so lieu
TAP C H ( KHOA HOC VA C O N G N G H E THUY LOl S6 39 - 2017 101
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mua dupe thu thap tu 20 tram khi tupng do mua nam trong luu vuc va eac thong so ciia phuang trmh RUSLE dupe liet ke a tren. Ket qua a hinh 4 the hien lupng mat dat trung binh nam do x6i mon be mat trong luu vuc song Lo.
Bang 4: B$ day trung binh lop dat xoi mon Trgm do
Bao Yen Thac Ba Ha Giang Ham Yen Bao Lac Chiem Hoa Tuyen Quang Vii Quang
B6 day ldp xoi mon 0,27 mm/nam 0,34 mm/nam 0,25 mm/nam 0,32 mm/nam 0,34 mm/nam 0,17 mm/nam 0,23 mm/nam 0,23 mm/nam
Hinh 4: Mdt ddt trung binh (tdn/ha/ndm) d luu vuc song L6
Dp day trung binh cua lap ddt xoi mon tren b^
mat luu vuc bang nam dupe xac dinh tir ket qua cua mo hinh RUSLE tinh toan luong mdt dat tnmg binh bang nam tai 8 tram quan trie thiiy van dupe the hien trong bang 4.
5.2. Ve h i ^ qua idng d^ng biin c^t trong ho chua H6 chua Thac Ba (dung tich 2,49-10^ m^) va ho chiia Tuyen Quang (dung tich 2,245-lO' m^) da thay doi ham lupfng bun cat trong dong chay ke tu nam 1971 (ho Thac Ba) va nam 2005 (bo Tuyen Quang). Bun cat lang dpng trong cae ho chiia nay da lam thay doi ham lupng bim cat la lirng trong song. Hieu qua lang dpng cua cae ho chira nay uac tinh trong khoang 71%-^95%. De danh gia su mat dat do xoi mon trong luu vuc song Lo, su dung mo hinh RUSLE va mo hinh DIMOSHONG dk tinh toan. Ket qua tinh toan thu dupe theo mo hinh tuang doi sat vai eac k£t qua thuc do tai 8 t r ^ thiiy van tren trong liru vuc song Lo dupe the bien trong bang 5.
Bang 5: T6ng lirong biin cat hang nam (tan/nam) Tr^m do
Bao Yen Thac Ba*
H i Giang Ham Yen Bio Lac Chiem Hoa*
Tuyen Quang*
Vii Quang*
S6ng Chay Chiy Lo Lo Gam Gim LoGam LoGamChay
Dien tich (km^)
5000 6170 8300 11900 4060 16500 29600 37000
Biin cat thuc do (khong ho)
4 315 193 3 221 854 3 018 636 4 254 671 1 181 968 5 411995 10 230 666 11000 128
Biin cat RUSLE (khong ho)
2 000 728 3 157 341 3 162 664 5 652 585 2 079 477 4 326 636 10 018 721 12 825 106
Biin cat thu'c do (CO ho) 4 315 193
186 249 3 018 636 4 254 671 1 181 968 1 868 613 3 915 373 4 188 439
Biin cat RUSLE (co ho) 1 851 864
639 120 2 630 838 4 755 346 2 079 477 1 222 592 4 087 866 4 225 354 (*) Cdc trgm a hg luu hd chua
TAP CHf KHOA HOC VA C O N G N G H E T H O Y L O I S O 39 - 2017
I KHOA HOC M E E B 3 ! 3 ! I ^ B
5.3. Ve su- thay dSi tham phii thyc vat dien tich dit rimg chuySn thanh dien tich dit Su thay d6i su dung dit da anh huong khong """S nghiep v i 15»/o thanh bui cay v i d6i Co, da nho d6i vdi xoi mon v i vin chuySn bun cit ' ™ '™S luong mit dit ciia luu vuc song Lo.
trong luu vuc song Lo. Do sir thay d6i lop phu ^^ 1™ ' " * '°™ * ™ ^° l™* RUSLE v i mo thuc vat: phi rimg dS phit triSn nang nghiep, *"•* DIMOSHONG cho thiy su thay dai su biSn dit rtmg thanh dit canh tic, hoang hoa dit ""vng dat vol dien tich dit rimg giam 35% nhu rimg va chiy rimg, theo Pham Hung [7] quan ' ^ " * " ^^ '™ ^V ™^' *^' '^° ™' ™™ t™? 1™
sit thiy dien tich rimg giam dSn 35%, voi 20% kh°™g 28% (xem trong bing 6).
Bang 6: Anh hudng thay flSi tham phu a i n t6ng lirong bun cat (tan/nam) lun vyc song Lo Tram do
Bao Yen Thic Ba*
Ha Giang Ham Yen Bao L^c Chiem Hoa*
Tuyen Quang*
Vii Quang*
S6ng Chiy Chay Lo Lo Gim Gam L6-Gam L6-Gam-Chay
Dien tich (km^)
5000 6170 8300 11900 4060 16500 29600 37000
Biin cat RUSLE 1 851 864
639 120 2 630 838 4 755 346 2 079 477 1 222 592 4 087 866 4 225 354
B i n cat RUSLE (thay doi tham
phu) 2 114 557
833 979 2 859 101 6 355 186 2 618 556 1580 741 5 724 311 5 968 811
Biin cat tang TB
(%)
28%
6. KET L U ^ N
Mua la yeu to quan trpng nhSt trong so eac nhan to anh huong den xoi mon be mat liru vuc. Phan tich so lieu mua thu thap tCr 20 tram do nua trong luu vuc song Lo cho thdy, khoang 83,3% t6ng lupng mua hang nam co cuong dp Ion ban 10 mm/ngay co dii nSng lupng dk gay nSn sir xoi mon dSt, theo Loureiro va Coutinho [5].
Mo hinh RUSLE kh hpp vai mo hinh DIMOSHOMG d% tinh toan lupng t6n thdt ddt do xoi mon va van chuyen bim cat trong song.
KSt qua tinh toan dupe chieu day lop ddt hk mat bj xoi mon trung binh hang nam tai tam tram do trong luu vuc song Lo: tai tram Bao Yen 0,27 mm/nam, tram Thac Ba 0,34 mm/nSm, tram Ha Giang 0,25 mm/nSm, tram Ham Yen 0,32 mm/nam, tram Bao L?e 0,34 mm/nam, tram Chieu Hoa 0,17 mm/nSm, tram
Tuyen Quang 0,23 mm/nam va tram Vii Quang 0,23 mm/nam.
Viec xay dung hai dap lan a luu vuc song Chay va song Gam tao nen h6 chiia Thac Ba va ho chiia Tuyen Quang da lam giam dang ke lupng bun eat la liing trong song. Su dung mo hinh RUSLE kk hop mo hinh DIMOSHONG tinh toan dupe lupng mat dat do xoi mon be mat va hieu qua lang dpng bun eat trong ho dat khoang 71%-^95%. Thay doi su dung dat da lam thay doi tham phu thuc vat trong luu vuc, vai gia dinh 20% dien tich dat rimg dupe chuyen doi thanh dat nong nghiep va 15% dien tich dat rimg bi hoang boa tra thanh doi co, cay bui thi co the lam tang len 28% lupng mat dat do xoi mon. Dieu nay cho thay mo hinh RUSLE kk hpp vai mo hinh DIMOSHONG CO the tinh toan dy bao xoi mon va van chuyen biin cat trong Iiru vuc song Lo, lupng biin cat
TAP C H ( K H O A H O C V A C O N G N G H ^ T H O Y LOI S6 39 - 2017 103
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ling dong trong cic ha chiia voi cic kich bin doi tip quin canh tic, chiy rimg va hoang h6a thay d6i tham phii thuc vat khac nhau do thay dat rimg.
TAI LIEU THAM KHAO
[1] Le T.P.Q., Gamier J., Gilles B., Sylvain T. and Chau V.M., 2007. The changing flow regime and sediment load of the Red river, Viet Nam. J. of Hydrol., 334, 199-214.
[2] Wischmeier W.H. and Smith D.D., 1978. Predicting rainfall erosion soil losses, A Guide to Conservation Planning. Agriculture Handbook N°. 282, N°. 537, U.S. Dep. Agr, Washington D.C.
[3] Renaid K.G., Foster G.A., Weesies D.A., McCool D.K. and Yoder D . C , 1997. Predicting Soil Erosion by Water: A Guide to Conservation Plarming with the Revised Universal Soil Less Equation (RUSLE). Agr. Handbook No.703, USDA, Washington DC.
[4] Le T.H., 2009, Sedunent load in the Lo river basin (Vietnam) and interaction with hydraulic structures, PhD thesis, Politecnico di Milano - Italia.
[5] Loureiro N.S. and Coutinho M.A., 2001. A new procedure to estimate the RUSLE E130 index, based on monthly rainfall data and applied to the Algarve region, Portugal, J. of Hydrol., 250, 12-18.
[6] Vezina K., Bonn F. and Pham V.C, 2006. Agricultural land-use patterns and soil erosion vulnerability of watershed units in Vietnam's northern highlands. Landscape Ecol 21 (8), 1311-1325.
[7] Pham H., 2007. Evaluating potential of soil loss erosion in the Ba Be lake basin in Vietnam, Project, Hanoi-Vietnam.
[8] Zhang K.L., Shu A.P., Xu X.L., Yang Q.K. and Yu B., 2008. Soil erodibility and its estimation for agricultural soils in China. J. of Ar. Env. 72, 1002-101.
[9] Moore I.D., Burch F.J., 1986. Physical basic of the length-slope factor in the Universal Soil Loss Equation. Soil Sci. Soc. of Am. L, Vol. 50,1294-1298.
[10] Ranzi R., Bochicchio M. and Bacchi B., 2002. Effects on floods of recent afforestation and urbanisation in the Mella River (Italian Alps), Hydrol. Earth System Sci., 6(2), 239-265.
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