T!J^}jJninJ 0,05mgN/l) xuit hien phia ngoai cira Van Uc Ticu ban Khi luang Thiiy van vil Dong liec hoc Bii cira Lach Tray, mdt phin nhd ven bd vinh Cat Ba Cac khu vuc khac d viing ven bien Hai Phdng thdi gian diu ed ham lugng NH4' nhd (< O.OlmgN/1) Chijnh lech ham lugng NHj* giira ting mat va day pha trieu khdng ldn qua trinh dgng lire manh mc cua ca ddng trieu va ddng chay sdng Tuy nhien cung cd the thiy pham vi viing nude cd ham lugng NH4' ldn tang mat d vung cira sdng Van lie so vdi ting day Su phan tail NH4' tir luc dia phia ngoai vung cira sdng ven bien Hai Phdng thi hien rd pha trieu xudng Dudi tac ddng cua truang ddng chay pha trieu nay, ddng NH4' khdng chi phat trien phia ngoai ma cdn cd xu hudng dich chuyen nhieu vl phia nam - lay nam theo hudng di chuyen cua cac khdi nude sdng tuong tu nhu sir di chuyln cua TSS Khu vuc cd ham lugng NH4* cao ngoai viing sat cac cita sdng, vinh Cat Ba cdn xuit hien d viing ven bd ban dao Dd Son Trong dd, khdi nude ting day d khu vuc giiia cua Nam Trieu va eiia Van IJc cd ham lugng NH4* nhd y Nhom muoi Nitorat (NOf): xu hudng lan trayin va bidn ddi cua NO3' miia mua d cac pha trii-u khac cung tuong tu nhu NH4* nhung vdi ham lugng ldn hon kha nhilu Trong pha trieu len cua mua mua trudng ddng chay ed huong tir phia biin vao cac cua sdng vi v,iy viing cd ham lugng NO3" eao bj day dan vc phia luc dja Tuy nhien luu lugng nude cua eac sdng tuong ddi ldn vao miia mua nen vung cd ham lugng NO3" cao (> 0,lmgN/l) xuiit hien d cac sdng, phia ngoai cira Van Uc, ctia Lach Tray, khu vuc tay nam dao Cat Hai, mdt phan nhd d ven bd vinh Cat Ba Cac khu vuc khac d vung ven bien Hai Phdng thdi gian deu cd ham lugng NO3" bien ddi khoang tir 0,05 den 0,lmgN/l Chenh lech ham lugng NO3' giira tang mat va day pha trieu khdng Idn qua trinh dgng luc manh mi; cua ca ddng trieu va ddng chay sdng -1- Nhom muoi phot (PO/'): pha trieu len, luu lugng nude eua cac sdng tuong ddi ldn vao miia mua nen viing ed ham lugng PO4' cao (> 0,03mgP/l) xuat hien d eac sdng, phia ngoai cua Nam Trieu va mgt phan nhd d ven bd vjnh Cat Ba Cac khu vuc khac d vimg ven biin Hai Phong thdi gian deu cd ham lugng PO4 thap (< 0,03mgP/l) Phan bd ham lugng POi'' d viing ven bd phia nam ban dao Dd Son tucmg ddi nhd so vdi vitng phia bic cd the la tai lugng phdt hda tan tir viing cua sdng Cam, Bach Dang va Lach Tray ldn hon so vdi song Van Uc khu vuc phia tay nam dao Cat Ba, bien dgng Clia ham lugng P04"'' theo thdi gian chit yeu hong khoang tir den 20 pgP/1 Bien dao ddng eua ham lugng PO4'" biin doi manh theo pha trieu va the hien su anh hudng cua cac ngudn dinh duong PO4'" tit viing cua sdng ya cd the khu vyc vjnh Cat Ba dua vdi cac cue dai dat dugc muc nude dat gia tri thap nhat va cue tieu vao cac thdi diem nude ldn Ham lugng PO4'" lap nude mat tugng doi ldn so vdi lop nude tang day, dae biet la vao nhitng cd bien dao ddng muc nude ldn Ci khu vyc phia nam va tay nam dao Cat Hai, vj tri gin cac ciia sdng cua phia bac ban dao Do San hon nen ham lugng PO4'' nugc cdn cd gia tri kha cao va biin dgng chu yeu khoang 15-35pgP/l IV KET LUAN Oing sir md phdng ba chieu eiia md hinh Delft3d eho thay chat ran lo liing anh huong din Idp nude tang mat manh ban so vdi cac lap nude d tang day Trong ea hai mua (mua tidt ngln Khou Iwc vii Cong nghe bien toiin iiuoc ldn thir va khd) ddng cac chit gay nhiem hihi co, dinh duong tu cac sdng d Hai Phdng it anh hudng den khu vue phia nam dao Cat Hai va Cat Ba Tuy nhien, khoi nude cd ham lugng hiru CO, dinh dudng eao di tir lue dja anh hudng nhieu den viing bai bien Do San va tay nam cira sdng Van Uc Dd nang cao chinh xac cua md hinh hon nua, cin xac dinh chi tilt cac ngudn thai dd khu vuc cac sdng va ven bd bien Hal Phdng TAI LIEU THAM KHAO Do Trgng Binh, 2003 U'ng eliing mi> hinh MIKE 21 de ddnh gid va die beio Ihuy diing li vit chiit heo-ng ineirc vinh Het Long Tuyin tap Tai nguyen va mdi trudng bien, tap IX, trang 33-51 Nxb KH&KT, Ha Ngi Do Trgng Binh Trin Anh Tu, Vd Duy VTnh, 2010 Nghien cieu ddnh gid lan truyen cite chill giiy nhiem khu vuc cita sdng ven bien Hdi Phong bang mo hinh toim hgc Bao cao Icing hgp de tai cap phd Hai Phdng Luu tru tai Vien Tai nguyen va Moi trudng bien Muila D J and Addiseott T M., 2005 Calibration and Validation of Water shed-Scale Models Vu Duy VTnh, 2005 Me") hinh todn nghien cieu thuy dgng liec vd chdt liegng nieffc khu viec Vinh Bdi Tie Long Tuyen tap tai nguyen va mdi trudng bien, tap XII, trang 33-51 Nxb KH&KT, Ha Ngi WL|Delft Hydraulics, 1999 Delft3D-FL0W User Manual Version i.05, DelftlD-Waq User Manual Version 3.01, Delfl3D-Part U.ser Manual Version 1.0 WL| Delft Hydraulics Delft, Netherlands ... vin xuat hien o d phia ngoai dai ven ba phia cua Van Uc, ciia Uchji Tray, khu vuc tay nam dao Cat Hai, mgt phin nhd d ven bd vjnh Cat Ba Cac khu vtrc kliat viing ven bien Hai Phdng thdi gian diu... md hinh lan truySn cac ch5t gay d nhidm [2] Phuo''ng phap Phuong phap md hinh toan sir dung ue nid phdng c h i dg thiiy dgng luc va lan truyjn cac chat gay d n h i i m khu vuc eua sdng ven bidn... dugc the hien [5] 2.1 Trien khai cdc mo hinh tinh todn khu virc cua song ven biin Hai Phdng + Md hinh thiiy dgng lire: eho khu vuc cua song ven bien Hai Phong su dung he ludi eong trirc giao Pham