Tap chi KHLN 4/2014 (3599 - 3613)
©, Vien KHLNVN • VAFS
ISSN 1859-0373 Dang tai tai www vafs gov vn
NGHIEN CU'U DAC DIEM LAP DjA VUNG DAM PHA VA VEN BIEN TINH THLTA THIEN HUE PHUC VU CONG TAG TRONG RU'NG NGAP MAN
Pham Ngoc Dung
Vdn phong Dodn DBOH vd HDND iinh Thira Thien Hut'
T O M TAT
Tir khda. Che dp thuy trieu, dp mSn. lap dja, rirng ngap man, Thira Thien Hue.
Ket qua nghien cuu da xac dmh dien tich dat ngap man co thg trfing rirng cila tinh Thira Thien Hufi la 2 765,8 ha. trong do viing ao nuoi thiiy san ha tvjh CO dien tich Ion nhSt, 2 502,5ha, chi^m 90,48%; tigp den la vung ven d^m pha, 206.9ha, chi^m 7,48%; viing cira song co 40,4ha, chi6m 1,46% va vung ven bi6n la nho nhat, chi c6 16.0ha, chiem 0,57% dien tich. Dk ngap man ciia Thira Thien Hue co dac tinh chung la chua; thanh phan co gioi thupc loai ddl cat pha voi ty IS cat biSn dong trung binh tir 80 - 90%; ddt giau kali long so, nhung ham luong lan, dam tong so va miin co su bien dpng kha Ion. tir muc ngheo den kha tiiy thupc timg viing ddt. Ddt o cac khu vuc cua song, ven bien va ao nuoi thiiy san giau dinh duong hon dat o viing ven dam pha. Theo dp mSn cua nuoc, dat ngap man cua Thira Thien Hue dupc phan chia thanh 05 viing.
Study on terrain characteristics of lagoon and coastal areas in Thua Thien Hue province for mangrove plantation
Keywords: Tidal regime, salinity, terrain, mangrove, Thua Thien Hue
The research results have identified that the wetland area for mangrove plantation of Thua Thien Hue province is 2,765 Sha, including the largest area ofthe low tidal aquaculture pond with 2,502,5ha, occupied 90 48% of the total area; the area belonging to the lagoon with 206 9ha. 7 48%, estuary area with 40.4ha, 1.46% and the smallest area o f t h e coast, only I6 0ha, accounting for 0.57%. The mangrove land of Thua Thien Hue province is generally sour; mechanical composition of sandy soil type with the fluctuation sand rate of average 80 - 90%; with rich potassium, but the concentration of phosphate, total nitrogen and humus with the large fluctuation, from the poor level to the medium level, depending on the region. Soil in the estuary, coastal area and aquaculture pond is more nutritious than in the lagoon. According to the salinity, the mangrove land is divided into 05 regions.
Tap chi KHLN 2014 Pham Ngpc Dung, 2014(4) I. DAT VAN DE
Thira Thien Hii^ la tinh co kha nhieu dien tich dSt ngap man (DNM) so vai cac dia phuang a mien Trung Viet Nam. Ngoai nhirng bai bdi a cac cira song, ven bien, tinh con CO he thong dam pha nuac Igf Tam Giang - Cau Hai rong 21.600ha va dam Lap An, rong 1.600ha (Sa Khoa hoc va Cong nghe Thira Thien Hue, 2004). Tuy nhien, dien tich rirng ngap man hien tai ciia tinh lai rat it, chi khoang 30ha, phan bo thanh tirng dam nho, rai rac a ven ba pha Tam Giang - Cau Hai va dam Lap An (Phan Nguyen Hong, 1999).
Trirac tinh hinh khi hau toan cau dang co nhirng bien doi lan, bat lai doi vai cupc song cua con nguai, thi viec phat trien them dien tich rimg ngap man tren dja ban tinh la hk sue can thiet. Thitc te thi viec trong rirng ngap man da dugc thuc hien kha sam tai Thira Thien Hue tir nhung nam 90 cua the ky XX. nhung ty ie thanh rirng thap do nhilu nguyen nhan, trong do co nguyen nhan quan trpng la do chua bo tri loai cay trong phii hpp voi dac diem lap dia cua tirng viing ngap man. Chinh vi vay, viec nghien ciru, danh gia dac diem lap dja viing dam pha va ven bi6n tinh Thira Thien Hue la nhu cdu khach quan va cdp bach nhdm tim ca sa khoa hoc cho viec xay dung giai phap ky thuat phu hgp dk phat trien thanh cong rirng ngap man tai tinh Thira Thien Hue.
II. PHl/ONG PIIAP NGHIEN CU'U 2.1. Phuong phap tai lieu
Kk thira k^t qua quan trSc dp man dd phuc vu hoat dpng nuoi tr6ng thiiy san ciia Chi cue Nuoi Thuy san tinh va cdc kk qua nghien ciru da co dk phdn tich dac dilm dp man cua nuac a cac \'iing d^t ngap tai Thira Thien Hue.
2.2. Phuong phap do do man, do sau ngap trieu, lay mau va phan tich dat
- Do dp man: Su dung khuc xa ke ATAGO: S - 28 CLia Nhat Ban de do bo sung do man cua nuoc tai cac kliu virc nghien cihi chua duoc nganh thuy san quan trac, gom cac khu vuc:
ven bien Tu Hien, ven bien Lang Co va diim Lap An.
- Do dp sdu ngap trieu: Quan trac lien tuc ca nam 2013. Do do sau ngap trieu hang ngay, mdi gio lay so lieu 01 lan tai 2 dilm quan trac dai dien cho 2 viing che dp trieu ciia tinh, gom diem so I dai dien cho viing CO che do ban nhat trieu deu dat a khu vuc giao nhau giira song Huang, pha Tam Giang va cira bien Thuan An, gpi la dilm Thuan An, diem so 2 dai dien cho vimg c6 chi dp ban nhdt trieu khong deu, dat 6 ven bi^n Lang Co.
- Lay mdu vd phan tich ddt: Ldy mdu ddt dl phan tich tai 17 khu vuc dat ngap man diln hinh ciia tinh theo phuang phap ciia Le Van Khoa va d6ng tac gia (1996). Tai m6i khu vyc Idy 2 mau hdn hap, mau thir nhdt o tdng 0 - 20cm, mau thu hai a tang 20 - 50cm. Phan tich tinh chdt cua dat tai Khoa Nong hoc, Truang Dai hpc Nong ldm Hul.
2.3. PhuoTig phap xay dung ban do khoanh vung lap dia dat ngap man
- Sir dung anh Bing Aerial, bdn quyln nam 2014 cua "Image Courtesy of NASA", Earthstar Geographies SIO va tap doan Microsoft, download tir trang web http://wvAv.bing.com/maps/, tich hgp vao phan mem Mapinfo ver. 12 va du lieu tpa dp dja ly cua cac dang lap dia dugc thu thap bang may djnh vi ve tinh GPS 76CSx dl khoanh ve cac viing lap dia ngdp man.
3600
Pham Ngoc Dung, 2014(4) Tap chi KHLN 2014 2.3. PhiroTig p h a p xir ly so lieu
Xu ly thong ke cac ket qua nghien ciru bang bang tinh tinh dien cua Excel (Nguyen Hai Tudt, Ngo Kim Khoi, 1996).
III. KET QUA NGHIEN CU'U VA THAO LUAN 3.1. Dien tich va p h a n bo ciia dat ngap man
& tinh Thira Thien H u e
Kit qud nghien cim da xac dinh ddt ngdp man (DNM) CO thi trong rirng ngap man (RNM) ciia tinh Thira Thien Hue gom 04 tieu viing lap dia la: (i) Tilu vimg lap dja DNM ao nuoi thuy san ha trieu; (ii) tieu viing lap dja DNM ven ddm pha; (iii) tieu vimg lap dja DNM cira song va (iv) tieu vimg lap dja DNM ven bien (Bang 1).
Bang 1. Dien tich va phan bo DNM ciia tinh Thira Thien Hue TT
1 2 3 4
T i l u vung lap dja Ao nuoi thuy san hg U\hu Ven dam pha Ciia song Ven bien
Phan bo Ven pha Tam Giang - C l u Hai va ven dSm Lap An
Pha Tam Giang - Cau Hai va ven d^m Lap An Cira song Hu'ang va song BLI LU CCfa bien Tu' Hign va ci>a bien Lang Co Tong cpng
Di#n tich (ha) 2,502,5
206,9 40.4 16.0 2 765,8
Tyl?
(%}
90,48 7,48 1,46 0,57 100
Kit qua bang 1 cho thdy, tfing dien tich DNM CO t h i trdng rirng ciia tinh Thira Thien Hul la 2.765,Sha, trong do vimg ao nudi thiiy san ha trieu co dien tich lan nhat, den 2.502,5ha, chilm 90,48%; tiep d i n Id viing ven ddm pha 206,9ha, chilm 7,48%; viing cira song 40.4ha, chilm 1,46% va viing ven
biln la nho nhdt, chi co 16,0ha, chiem 0,57% dien tich.
Tir kit qua dieu tra khdo sat thuc dia, ket hap sii dung anh vien tham da xac dinh dugc dien tich va khoanh ve dugc ban dd phdn bd chi tilt ciia timg loai lap dia DNM theo dja ban huyen, xa nhu sau:
3. I.I. Tiiu viing lap dia diit ngdp man ao nudi thuy sdn ha trieu
Bang 2. Dien tich va phdn bd ciia DNM ao nudi thiiy san ha trieu TT
1 2 3 4 5
Huyfn Phong Oien Quang Dien Hi/cyng Tra Phu Vang Phu Lpc
Cpng
Difn tich (hai 19,7 603.6 267,9 705,8 905,5 2502,5
Tyl?
(•/.) 0,78 24,11 10,70 28,20 36,18 100
Tap chi KHLN 2014 Phgm Ngpc Dung, 2014M)
Hinh 1. Phan bd dat ngdp man ao nudi thiiy san h?i trieu (vung mdu vdng) va ven dam pha (vimg mdu do) a Thira Thien Hue Kit qua bang 2 va hinh 1 cho thdy, ao nuoi
thiiy sdn ha trieu chii yeu phan bo dpc ven bd pha Tam Giang - Cau Hai (2,461,Sha, chiem 99.2%). trong do huyen Phil Lgc co nhieu dien tich nhat. din 905.5ha. chiem 36,18%, phdn bd tren 12 xa va thi tran, tiep den la huyen Phu Vang, 705,8ha, chilm 28,2%, phdn 3.1.2. Tieu viing lap dia ddt ngap man ven ddm phd
Bang 3. Chi tiet dien tich va phdn bd ciia ddt ngdp man ven dam pha bd tren 14 xa va thi trdn; huyen Quang Dien cd 603,6ha, chilm 24,1 \%, phan bd tren 7 xa va thj trdn; thi xa Huang Tra cd 267,91m, chilm 10,7%, phdn bd tren 2 xa. thdp nhk la huyen Phong Dien, chi cd 19,7ha, chiem 0,78%, duy nhat a xa Dien Hai.
TT 1 2
Dja diem Pha Tam Giang - Cau Hai 0am Lap An Tpng cpng
Di^n tich (ha) 122,4
84,5 206,9
Ty 1?(%1 59,16 40,84 100,00
Loai DNM nay phdn bd dpc ven bo pha Tam Giang - Cdu Hai va dam Lap An. Trong do, ven pha Tam Giang - Cdu Hai co 122,4ha, chiem 59,16%. phan bd a 15 xa va thi trdn.
thugc 04 huyen Qudng Diln, Huong Tra, Phu Vang va Phu Lpc; ven dam Lap An co 84,5ha, chilm 40,84% (Bang 3 vd Hinh 1).
Phgm Nggc Dung, 2014(4) Tap chi KHLN 2014
3.1.3. Tieu vung lap dia ddt ngdp man cira sdng
Bang 4. Chi tiet dien tich va phdn bd ciia dang lap dia DNM cua sdng
TT 1 2
Dja diem Cua song Hucyng Cua song BO Lu Cpng
Di^n tich (ha) 28,9 11.50 40,4
Ty 1? (%) 71,53 26.47 100.00
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Hinh 2. Phdn bo ciia lap dia DNM cua sdng 6 Thira Thien Hul (a) DNM d cira sdng Huong; (b) DNM d cira sdng Bii Lu Ket qua bang 4 va hinh 2 cho thay, DNM cira
sdng 6 Thira Thien Hue chi co 6 khu vuc cira sdng Hucmg va cira sdng Bii Lu, dien tich chi CO 40,4ha, trong do khu vuc cira sdng Huong cd 28,85ha, chiem 71,53%o va khu vuc cira sdng Bu Lu cd 11,50ha chilm 28,47%.
3.1.4. Tieu vung lap dja ddt ngap man ven bien Ket qua nghien cuu da xac dinh chi co vimg ven cua bien Lang Co (thj tran Lang Co) va ven cira bien Tu Hien (xa Vinh Hien) thupc huyen Phu Lgc la cd cac bai ddt bdi ngap man vai dien tich la 16,0ha, trong do khu vuc ven bien Lang Cd co 10,56ha, chiem 65,63% va khu vuc ven bien Tu Hien c6 5,63ha, chiem 34,37% (Bang 5 va Hinh 3).
Bang 5. Chi tiet dien tich va phan bd ciia dat ngap man ven bien
TT 1 2
Dja diem Ven bien Lang Co Ven bien Tu" Hien Cong
Di^n tich (ha) 10.5 5.5 16,0
Ty If (%) 65.63 34.37 100.00
+
X .IL-V--,
Hinh 3. So do phan b6 cua DNM ven bien a Thira Thien Hue
m
(a) DNM o ven bien Lang Co; (b) DNM 6 ven bien Tu Hien
Tap chi KHLN 2014 Pham Ngoc Dijng, 2014(41 3.2. Dac dilm dat ngap man tinh Thira
Thien Hue
3.2.1. Dp man ciia nudc
Dp man cua nudc la nhdn td sinh thai quan trpng, anh hudng ldn din sy phdn bd cua cay ngap man (CNM). Viec xac dinh duoc dp man
Bang 6. Diln biln dp man trung binh theo thang trong nam 2013 6 cac tilu viing lap dja DNM ciia nudc cd y nghTa rat quan trpng, giup lya chpn, bd tri diing c a cau cay trdng RNM cho tirng viing. Ket qua quan trac dp man nuac nam 2013 tren cac viing DNM cua tinh dupc trinh bay tai bang 6.
Tiiwi gian
01-15/1 16-31/1 01 -15/2 16-30/2 01 -15/3 16-31/3 01-15/4 16-30/4 01 -15/5 16-31/5 01 -15/6 16-30/6 01 -15/7 16-31/7 01 -15/8 16-31/8 01 -15/9 16-30/9 01 -15/10 16-31/10 01 -15/11 16-30/11 01 - 15/12 16-31/12
cua tinh Thira Thien Hue (%o) Dja diem i<tiao sat Tieu vilng iap
dja CLFa song
Ci>aS.
Hu-cng
5 5 7 7 12 12 12 14 14 16 15 18 21 22 20 16 8 3 4 4 4 5 6 6
Ci>a S. Bu
Lu 8 8 12 15 12 14 14 15 15 18 18 20 22 24 21 20 10 5 5 5 8 6 6 8
Tieu vijng lap dia ven b i l n
TIP Hiin
17 18 19 23 19 20 21 22 31 32 31 32 32 31 31 30 20 15 12 10 9 12 14 12
Lang 06
18 18 20 21 21 22 24 24 30 31 31 32 32 32 32 32 22 18 15 14 12 12 15 15
Tieu vung lap dja ven d^m pha Pha Tam Giang - Cau Hai Di4n
Hai 0 0 0 0 0 2 3 4 4 5 7 8 7 8 8 8 4 0 0 0 0 0 0 0
Sia 2 2 9 10 5 12 13 7 8 11 10 11 15 15 12 16 8 2 0 0 0 0 2 0
Thuan An
15 16 25 17 21 24 20 26 22 24 27 24 25 28 28 30 20 18 15 10 12 9 8 10
Sam Chudn
12 12 18 20 16 19 19 20 20 22 25 22 24 25 24 23 18 12 10 10 12 8 7 8
Thuy T i i - H a
Trung 8 10 12 14 15 16 18 20 18 20 21 19 20 20 18 20 16 10 7 8 9 6 6 6
C l u Hai 8 12 15 16 16 14 14 18 25 26 22 21 25 21 19 18 12 9 0 0 0 0 3 3
Diim Lap
An 18 18 20 21 21 22 24 24 30 31 31 32 32 32 32 32 22 18 15 14 12 12 15 15
Tilu vCing lap dja ao nuoi thuy san ha
trilu
Tuong dong voidg man nuoc ciia lap dja ven dim pha tai
tiing khu Vl^c phan b l
Pham Ngpc Dijng, 2014(4) Tap chi KHLN 2014 Ket qud nghien ciru cho thay cd su tuong
ddng ve dp man nuac ciia vimg ao nudi thuy san ha trieu vdi dp man nudc ciia viing ven dam pha, dp man ciia nuac trong ddm Lap An voi dp man cua nuac a ven biln Lang Cd phia ngoai cira ddm. Nguyen nhdn la do ao nuoi thiiy sdn ha trilu d sat bd ddm, phd, chi trao ddi nudc true tiep voi ddm pha thdng qua he thdng cdng tren cac bcf ao va cac kenh dan nudc tir ddm pha vac ao; nuoc trong ao hoan toan la nudc ciia dam pha, nen dp man cua nudc trong ao chinh la dp man ciia nudc tren dam pha. Tuong tu nhu vay, do dam Lap An cd dang nhu mpt tui nuac ldn an sau vao ddt lien, hoan todn biet lap vdi cac dam phd khac trong he thdng dam pha ciia tinh Thira Thien Hue, chi thdng vdi bien Lang Cd qua cira dam; mac ddu xung quanh ddm cd mpt sd con sudi, nhung do luu lugng nhd, lupng nudc ngpt dd vao ddm thap, nudc trong dam chii yeu la nudc thiiy trieu, nen co dp man tuang tu dp man ciia nuoc a vimg ven bien ngoai cua dam.
Kit qua bang 6 cung cho thdy dp man ciia nudc d cac viing DNM cd bien ddi Ion theo khdng gian va theo thai gian, cu the:
- Bien doi theo khdng gian: Nhin chung dp man ciia nudc giita cac viing DNM rat khac nhau va ngay trong ciing mpt xiing ciing cd nhiing khac biet nhdt djnh. Cu the:
+ Viing ven biln cd dp man ldn nhat, bien dong tir 9 - 32%o, tilp d i n la vung ven ddm phd, tir 0 - 32%o; viing cua sdng cd do man thap hon, bien dpng tir 3 - 22%o.
+ Viing ven ddm pha co dp man biln ddng rat ldn va phan hoa thanh nhilu tieu viing dp man khac nhau. Trong dd, ddm Lap An biet lap vdi cac ddm pha khac, trao ddi nuac true tilp vai hien Lang Cd, cd do man cao va dn djnh nhat, tir 12 - 32%o. Pha Tam Giang - Cdu Hai rdng han 22.000ha, trai dai tren 68km, bao gdm 04
ddm ndi nhau tir Bac xudng Nam Id pha Tam Giang, dam Sam - Chudn, dam Thuy Tii - Ha Trung va ddm Cdu Hai.
Pha Tam Giang keo dai tir xa Dien Hdi den thi trdn Thuan An. cd dp man cua nudc tang dan theo hudng Bac - Nam. Khu vuc Dien Hai cd dp man thap nhat, bien dpng tir 0 - S%o; khu vuc thi trdn Sia it chju anh hudng cua sdng 6 Lau va gdn cira bien Thuan An nen cd dp man cao hon khu vyc Dien Hdi, bien dpng tir 0 - 16%o; khu vuc Thudn An cd dp man cao nhat trong toan pha Tam Giang - Cdu Hai, biln ddng tir 8 - 30%o.
Dam Sam - Chudn, cd dp man bien ddng tir 8 - 25%o.
Dam Thiiy Tii - Ha Trung tiep ndi vdi Sam - Chudn, do nam d giiia 2 cira bien Thudn An vd Tu Hien, cd su trao ddi nudc tdt giiJa 2 cira bien nen cd dp man dn dinh nhdt so vdi cac kliu vuc khac ciia pha Tam Giang - Cau Hai;
bien dpng tir 6 - 21%o.
Ddm Cdu Hai cd dp man bien ddng tdn va thieu dn dinh, dao dpng tir 0 - 26%o. Do d gdn cira bien Tu Hien, nen dp man ciia nudc d viing nay thuang cao han ddm Thiiy Tii, nhung khi cd 111 lut thi dp man d ddm Cdu Hai giam rdt nhanh do chiu anh hudng xd lii tir hd Trudi.
+ Viing cira sdng: Do man ciia nudc d ciia sdng Bu Lu thuong cao hem d cira sdng Huong tir 2 - 5%o; dieu nay la do song Huong do vao pha Tam Giang trong khi song Bii Lu dd thang ra bien Ddng, nen muc dp nhiem man cao han.
- Bien doi theo thoi gian: Diem chung nhat giira cac tieu viing lap dia la dp man d miia khd cao hon nhieu so vdi dp man d miia mua.
Tai Thira Thien Hue, miia mua bat ddu tir thang 9 den thang 12; miia khd bat dau tir thdng 4 den thang 8. Vao miia mua, thang 10 va 11 Id thdi gian cd luong mua Ion nhat trong nam, ciing la thdi ky xay ra lu ldn, nen
Tap chi KHLN 2014 Pham Nggc DiJng, 2Ql4(4j^
mdi trudng nudc ciia nhieu khu vuc dam pha bi nggt hda, dp man chi con 0%o; tir thang 5 den thang 8, dugc xem la thdi ky man hda, dp man co thi tren 30%o d cac viing ven cira bien.
+ Dp man nudc ciia viing ven bien rat cao trong miia khd, tu 21 - 32%o; vao mua mua, dp man cd giam, bien dpng tir 9 - 22%o, nhung van cao han nhieu so vdi cac viing khac.
+ Dp man cua nudc d cua sdng Hucmg va sdng Bii Lu trong miia khd kha cao, dao ddng tir 15 - 22%o; vao miia mua, dp man giam thap, bien dpng tir 3 - 10%o; thdi gian cdn lai trong nam, thudng dao ddng trong khoang tir 12 - 20%o. Thuc te, van cd nhirng thdi diem nudc d cira sdng Hucmg va cira song Bii Lu bj ngpt hda hoan toan, dd la nhimg liic lu ldn, nudc d thugng ngudn sdng Huong va sdng Bii Lu do ve nhieu, da day khdi nudc man ra ngodi ciia bien. Tuy nhien thdi gian ngpt hda thudng chi keo dai vai ngdy, khi nudc 10 yeu, nudc man se theo thuy trieu xam nhap vao cira sdng lam tang dp man cua nudc d khu vuc nay.
+ Dp man nudc cua pha Tam Giang - Cdu Hai bien ddng rdt ldn va thieu dn dinh giiia 2 miia, nhat la cac khu vuc Diln Hai, Sja va Cdu Hai:
Khu vyc Dien Hai hoan todn bi nggt hoa trong miia mua va keo dai sang ca din thang 3 nam sau (6 thang ngpt hda/nam); vao miia kho, nudc ciia khu vuc nay cd dp man, nhung van rat thap, khdng qua 8%o.
Khu vyc Sia cd dp man cao hem Diln Hai, nhung vdn bj ngpt hda vao 2 thang mua nhilu la thdng 10 va 11; do man dao ddng tir 0 - 8%o vao miia mua va tir 7 - 16%o vao miia khd.
Ddm Cau Hai cd dp man dao ddng trong khodng tit 0 - 1 l%o vao miia mua va lir 14 - 25%o vao miia khd. Ddy la noi cd biln dpng dp man cua nudc ldn nhdt trong tdt ca cac viing ddt ngap man ciia tinh Thira Thien Hul.
Dya vao thang phdn chia dp man Venice (1958) (Tdn Thdt Phdp, 1993), vdi cdc trj si lam diem moc de phdn bac gdm:
- Nudc ngpt: S%o < 0,5%o;
- La nhat: 0,5 < S%o < 5%o;
- Lp vira: 5%o < S%o < 18%o;
- L a man: 18<S%o<30%o;
- La qua man: 30%o < S%o < dp man ciia vimg bien tiep can thi cd the chia DNM ciia tinh Thira Thien Hue thanh 5 \amg dp man nhu sau.
Viing 1: Cd mdi trudng bien ddi chii yeu giiia nudc ngpt va la nhat, tieu bieu cho vimg nay ia Idiu vyc Dien Hai d cyc bac cua pha Tam Giang Viing 2: Cd mdi trucmg bien ddi chii yeu giiia nudc ngpt, lp nhat va la vira, tieu bieu cho viing nay la khu vuc Sia thupc pha Tam Giang.
Vimg 3: Cd mdi trudng bien ddi chii yeu giiia nudc nggt, lp nhat, la vira va la man, tieu bieu cho viing nay la dam Cdu Hai va cac khu vyc cira sdng Huang, cua sdng Bii Lu.
Viing 4: Cd mdi trudng bien ddi chii yeu giira ip vira va lp man, tieu bieu cho vimg nay la cac khu vyc Thuan An, ddm Sam Chudn, ddm Thiiy Tu - Ha Trung thupc pha Tam Giang - Cau Hai.
Viing 5: Cd mdi trudng bien ddi chii ylu giiia lp vira, Ip man va lg- qua man, tieu bieu cho viing nay la cac khu vyc ven biln Tu Hiln, ven biln Lang Cd va ddm Lap An.
3.2.2. Che dp thuy trieu vd dp sau ngap trieu
& cdc vung DNM 3.2.2.1. Che do thuy trieu
Viing biln ven bd Thira Thien Hul cd thiiy trieu bien ddi khd phirc tap. Viing ven bien Ian can cira Thuan An thupc chi dp ban nhdt trilu deu, nai day cd dao dpng thiiy trilu nhd nhat trong toan dai ven bd cua Viet Nam, chi khoang 0,30 - 0,50m; khu vuc phia Nam cua tinh gdm vimg ven bien cira Tu Hien va Lang
Pham Ngpc Djjnq. 2014(4) Tap chi KHLN 2014
Co tliuoc huyen Phu Loc, thuy triju chuygn sang che do Mn nhat triSu khong dhu (Le Van Khoa elal, 19%).
Thiiy trieu ciia viing dSm pha, cira song hinh thanh do cam ting triSu ngoai bidn thong qua cac cira bien (Le Van Khoa el al., 1996), nen cung CO 2 che dp trieu. Viing dim pha, cira song thuoc cac huyen Phong Diin, Quang Dien, Huong Tra va phu Vang (g6m pha Tam Giang, cira song Huong, ikm Sam - Chu6n, dam Thiiy Tii) chiu anh huong ciia tridu o cira Bang 7. Che dp thuy trieu a cac
bien Thuan An nen co che dp ban nhat trieu deu; viing dam pha. cira song, ven bien thuoc huyen Phii Loc (gom dam Cau Hai, cira song Bii Lu, ven bien Lang Co, ikm Lap An) chju anh huong ciia trieu a cira bidn Tu Hidn va Lang Co nen co che dp ban nhat tridu khong deu. Do trap doi nuac true tiep vai dam pha, nen che dp thiiy trieu trong cac ao nuoi thuy san tuang tir che dp thiiy tridu tren cac d^m pha (Bang 7).
viing DNM cua Thira Thien Hud
Dja diem 1. Vung ven d^m pha - Pha Tam Giang -Dam Sam - Chuon - Dam Thuy Tu - D i m Cau Hai - Dam Lgp An 2 Vung ao nuoi thuy san hg tnlu
3 Vung cua song - COa song Hu'cng - Ci>a s6ng Bu Lu 4. Vung ven bien - Ven bien TiK Hien - Ven bien Lang Co
C h i dp thuy t r i l u Ban n h | t t r i § u d l u
X X X
Ban nhat tridu khong d i u
X X Tu'ong tiy vung ven d i m pha
X
X
X X
3.2.2.2. Dp sdu ngdp trieu
Ket qua quan trac thuy trieu nam 2013 tai 2 diem Thuan An va Lang Cd, dai dien cho 2 chi dp thiiy trieu the hien qua bang 8 va hinh 4.
Bang 8. Dien bien muc nudc trieu nam 2013 khu vyc Thudn An va Lang Cd
Ttio-i gian
1/1/2013 10/1/2013 20/1/2013 1/2/2013
Khu v v c Thuan An (Ban nhat trieu d i u ; DVT; m) IVIi/c nu'O'C
cao nh^t 0.35 0.29 0.26 0.25
lUli^rc nu'O'C t h i p n h i t 0.15 0.08 0,10
•0.17
Trung binh 0.25 0.19 0.18 0.04
Khu vyc Lang Co (Ban nhat t r i l u Ichong d i u ; DVT: m) IVIyc nu'O'C
cao n h l t 0.52 0.44 0.41 0.40
Myc nyo'C t h i p n h l t
0.00 -0.08 -0.06 -0.35
Trung binh 0,26 0.18 0.18 0.03
Pham Ngpc Dung. 2014f«
P
Thcri gian
10/2/2013 20/2/2013 1/3/2013 10/3/2013 20/3/2013 1/4/2013 10/4/2013 20/4/2013 1/5/2013 10/5/2013 20/5/2013 1/6/2013 tO/6/2013 20/6/2013 1/7/2013 10/7/2013 20/7/2013 1/8/2013 10/8/2013 20/8/2013 1/9/2013 10/9/2013 20/9/2013 1/10/2013 10/10/2013 20/10/2013 1/11/2013 10/11/2013 20/11/2013 1/12/2013 10/12/2013 20/12/2013 30/12/2013
Khu vyc Thuan An {Ban nttat t r i l u d i u ; DVT: m) li/lyc nuoc
cao nhlt 0.34 0.11 0.28 0.10 -0.04 0.23 0.38 0.00 0.16 0.19 0.07 0.04 0.09 0.15 0.13 0.09 0,15 0.17 0.09 0.15 -0.10
0.28 0.61 0.85 0.42 0.73 0.52 1.20 0.66 0.49 0.31 0.27 0,34
IWyc nyac ttilp nhlt 0,03 -0.10 -0.20 -0.08 -0.16 -0.20 -0.18 -0.15 -0.20
•0.22 -0.25 -0.30 -0.25 -0.25 -0.28 -0.35 -0.25 -0.08 -0.23 -0.20 -0.19 -0.06 0.38 0.40 0.17 0.47 0.20 0.90 0.54 0.20 0.08 0,02 0.09
Trung binh 0.19 0.01 0.04 0.01 -0,10 0.02 0.10 -0,08 -0.02 -0.02 -0.09 -0.13 -0.08 -0.05 -0.08 -0.13 -0.05 0.05 -0.07 -0.03 -0.15 0.11 0.50 0,63 0.30 0.60 0.36 1.05 0.60 0.35 0.20 0.15 0.22
Khu v y c Lang Co i ^ _ (Ban nhat t r i l u t<h6ng d i u ; DVT: m) Myc nyoc
cao n h l t 0.52 0.26 0.45 0.25 0.13 0.38 0,53 0.15 0.31 0.34 0,25 0.22 0.24 0.30 0.28 0,25 0,30 0.32 0.26 0,30 0.05 0.45 0.72 0.95 0.57 0.82 0.59 1,10 0,83 0.62 0,46 0.42 0.45
Myc nyac t h i p nhat
•0.12 -0.25 -0.35 -0.25 -0.31 -0.35 -0.33 -0,32 -0,35 -0,37
•0.40 -0.45 -0.40 -0.40
•0.45
•0.50 -0,40 -0.25 -0.38 -0.35 -0.35 -0.22 0.06 0.25 0.03 0,32 0.05 0.72 0.38 0.05 -0.06 -0.15 -0.07
Trung binh 0.20 0.01 0.05 ,.j 0.00 ,
•0,09 ' 0.02 0.10 - 0.09 - 0.02 -0.02 -0,08 -0.12 -0.08 -0.05
•0,09 -0.13
•0.05 0.04 -0.06 -O03 -0.15 0.12 0.39 0,60 0.30 0,57 0.32 0.91 0.61 0.34 0.20 0.14 0.19
3608
Phgm Nggc DCrng. 2014(4) Tap chi KHLN 2014 1,40
1,20 0,80 0,60 O40
0,20 M A I' ^ __
0.00 ^ ^ ', ! '^
-0,20 5 g s s ' ' § > . , 3 _ 2 -0,60 - " - - ' - - ' -
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Hinh 4. Dien bien muc nudc trik nam 2013: (a) khu vyc Thudn An, (b) Khu vyc Lang Cd Ket qua bang 8 \'d hinh 4 cho thdy ngoai 2
thang 10 va II, muc nudc triSu d ca 2 khu vyc cd sy tang cao bat thudng do lu lut ldn, thi cac thdng cdn lai trong nam, myc nudc trieu d cac khu vyc kha dn djnh. Bien dp tri^u cao nhdt d khu vuc Thuan An la 0,6m; d Lang Cd Id 0,9m. Vao miia mua, nhdt la cac thang 10, 11 va 12, muc nudc d viing ddm pha va cira sdng ludn cao han myc nudc bi^n, nen cac viing dat nay deu ludn d trong tinh trang 3.2.3. Mdt sd ti'nh chdt ly hda tinh cua ddt ngap man
Bang 9. Mdt sd tinh chat ly hda tinh ciia DNM d tinh Thira Thien Hud
bj ngdp nudc. Nhung vao miia khd, nhdt la cac thang 5, 6, 7 va 8, muc nudc d cac vimg nay thudng thap hem myc nudc bien. 6 Thuan An thdp hem tir 10 - 20cm, cd thdi dilm len den 30cm; d Lang Cd thdp hon tir 20 - 40cm, cd thai diem len den 50cm. Do dd, vao cac thang 6, 7, 8, phan ldn cac bai bdi d cua sdng, ven pha va ven bien deu can nudc tir 12 den 16 gid/ngay.
T i l u vung DNM
Vung cua song
Viing ven bien
Vung ven dam pha
Dja d i l m
Cua Song Hyong Cua song Bii Lu Ven bien LSng Co Ven bien Ty Hien Dong pha Tam Giang Tay pha Pha Giang 3am Sam • Chuon
D9 sau (cm) 0^20 2 0 - 5 0 0 - 2 0 2 0 - 5 0 0 - 2 0 20^50 0 ^ 2 0 2 0 - 6 0 0 - 2 0 2 0 - 5 0 0 - 2 0 2 0 - 5 0 0 - 2 0 2 0 - 5 0
PHKCI
5,37 5,00 5,63 5,12 5,98 5,87 5,87 5,96 4,77 4,68 4.05 3.34 3.97 3.61
Mun
1.65 1.45 2.69 2,39 2,45 2,38 2,28 2.17 1.96 1.86 1,81 1,80 2.37 2.23
N
(%)
0.150 0.135 0.180 0.165 0.132 0.124 0.082 0.077 0.074 0.066 0.055 0.053 0.164 0.165
PiO,
(%)
0.048 0.042 0.054 0.042 0,137 0.110 0.116 0.108 0.125 0.101 0.024 0.020 0.022 0,020
KjO
(%)
0.43 0.40 0.63 0.54 0.49 0.42 0.65 0.63 0.83 0.77 0.31 0,27 0,77 0,69
Thanh p h i n co* gioi {%) Cat
84,6 79,8 84.7 78.9 81.3 74.9 88,8 87.9 85.7 83.5 91.2 89.3 87.7 84,6
Thjt 1.1 1.5 3.3 6,1 4,4 6,7 4,4 3,3 1,1 2,0 1,1 1.4 6.0 3.3
Set 14.3 18.7 12 15 14.3 18.4 6,8 8,8 13,2 14,5 7,7 10.1 6.3 12.1
Tap chi KHLN 2014 Pham Ngpc Dung, 2014(4|
DNM
VCing ao nuoi thuy san ha tnlu
Dja diem
Dong 6km ThCiy TO - Ha Trung Tay dim Thiiy Til - Ha Trung Dong SSm c l u Hai Tay dim Cau Hai Dong dim Lgp An Tay dim Lgp An Dong pha Tam Giang Tay pha Tam Giang Dim Sam Chudn Tay dim Thuy TLI - Ha Tmng
Do sau (cm) 0 - 2 0 20-50
0 - 2 0 20-50
0 - 2 0 20-50
0 - 2 0 20-50
0 - 2 0 20-50
0 - 2 0 20-50
0 - 2 0 20-50
0 - 2 0 20-50
0 - 2 0 20-50
0 - 2 0 20-50
PHKCI
5,60 4.36 4,85 4,63 4,30 4.12 4,31 4,40 5.88 5,33 5,55 5,53 5.67 5,37 5,68 5,11 5,02 4,44 5,13 4.83
Mun
(%)
0.57 0.41 1.64 1.60 1.03 0.94 1.59 1.45 2.79 2.55 2.48 2.17 2.69 2.49 2.06 1.44 1.74 1,55 2,26 1.85
N
(%)
0.056 0.050 0.086 0.066 0.084 0.075 0.087 0.081 0.108 0.090 0,105 0.102 0,101 0.091 0.077 0.063 0.135 0.117 0.106 0.085
P2OS
(%)
0.021 0,024 0,054 0,050 0,038 0.036 0.063 0.045 0.150 0.145 0.070 0.068 0.128 0.061 0.049 0.040 0.050 0.034 0.084 0.075
KiO
(%)
0.18 0.13 0.68 0.63 0.23 0.20 0.52 0.51 0.73 0.74 0.61 0,50 0,78 0.70 0,87 0.86 0.59 0.38 0.68 0.63
Thanh p h i n CO gioi (%) Cat
92.3 91.1 89.9 86.8 90.1 84.6 87.9 86.8 82.9 80.2 91.9 89,9 74.8 76.9 81,1 71.0 86.8 78.9 87.0 85.5
Thjt 4.4 3.9 1,0 1,1 2.2 5.8 4.4 4.8 7.1 5.5 3.3 4.1 17.3 16.8 13.7 21.8 4.4 7.5 2.5 2.2
Set 3.3 6.0 9,1 12.1 7.7 9.6 7.7 8.4 10.0 143 4.8 6.0 79 6.3 5,3 7,2 8.8 13.6 10.5 12.3
Ket qua bang 9 cho thay DNM a tinh Thua Thien Hue co dac diem chung la dat cat va chua; ham lugng dam, lan, kali tong so va mun tai cac diem khao sat khong co su khac biet lan giua tang mat va tang duai. Tuy nhien, tfnh chat, dac diem ciia dat a cac ti^u vung lap dja co su khac nhau ro ret.
- Vung cii'a song Huong va song Bit Lu: DSt a ving nay thuoc loai it chua (pH tir 5,0 - 5,63); giau kali tdng s6 (0.40 - 0,63%), dam t6ng so cr mile kha (0,14 - 0,18%) nhung ham lugng lan tdng so va mun b miic tir ngheo djn trung binh (lan: 0,042 - 0.054%>; mim: 1,45 - 2,69%). Thanh phan co gioi thupc loai dSt cat
pha set, tang duai co nhieu set hon tang tren (ty le cat biin dgng tit 78,9 - 84,7%; ty le set va thit kha cao, tir 15.3 - 21,1%).
- Vung ven bien Tu- Hien va Lang Co: Dat viing nay it chua hon vimg cira song (pH tit 5,88 - 5,98), giau kali tfing s6 (0,42 - 0,65%), lan t6ng s6 6 mirc kha (0,108 - 0,137%), trang binh ve dam tong so va mim (dam: 0,08 - 0,13%; mim: 2,17 - 2,45%). Thanh phin co giai thugc Igai dat cat pha set, tang duoi co nhieu set hon tSng tren; dang chu y dat a ven bien Lang Co co ham lugng cat thap nhat trong cac Igai DNM ctia tinh.
3610
Pham Ngpc Dung, 2014(4) Tap chi KHLN 2014
ViJng ven dam pha: Dat viing nay cd dac diem chung la chua, ngheo dinh duang va cd ham luang cat cao ban d^t d cac lap dja khac.
Do dia ban rdng lan, trai dai ghn het toan bd viing ven biln ciia tinh nen tinh chk, dac didm cua dat d cac khu vuc cd sir khac nhau rd ret;
ddng thdi, ngay trong ciing mot khu \ uc cung cd sir khac nhau giiia d^t d ven bd Ddng va dat d ven ba Tay, cu the:
+ Pha Tam Giang: DSt vimg nay cd pH thkp (tir 3,84 - 4,77) nen rk chua. dk o bd Tay chua hem a bd Ddng. Bk giau kali tdng sd (0,27 - 0,83%) nhung ngheo dam tdng sd va miin (dam: 0,056 0,074%; miin: 1.81 1,96%); bd Tay ngheo lan tdng sd han bd Ddng. Thanh phan ca giai cd ty le cat chiem kha cao, tren 85% ca tang tren va tang dudi, bd Tay cd ty le cat cao han hb Ddng (91,2%
so vdi 85,7%); phan set trong dat cao ban nhieu so vdi phan thit (set bien ddng tir 10,1 - 13,1%; thjt bian ddng tir 1,1 - 1,4%).
+ Dam Sam - Chudn: Dat d day rat chua do pH rat thap (tir 3,61 - 3,97); ty le cat kha cao, tren 85%; ty le set va thit deu nhau d tang tren (6,0 va 6,3%), nhung d tang dudi thi phan set ldn gSp 4 ian phhn thjt (12,1% so vdi 3,3%).
Mac dau lan tdng sd a muc ngheo (0,020 - 0,022), tuy nhien thanh phan dinh duang ciia dk a viing nay kha hon dat d ven pha Tam Giang, the hien qua cac chi sd: Kali tdng sd d miirc giau (0,69 - 0.77%), dam tdng sd d mirc kha (0,155 - 0,164%) va ham lugng mun d mirc trung binh (2,23 - 2,37%).
+ Dim Thiiy Tu - Ha Trung: Dat chua (pH tir 4,36 - 5,6) va cd ty le cat cao nhit (tir 89,9 - 92,3%) so vdi ddt d cac viing khac trong he dam pha Tam Giang - Cau Hai. Ham lugng cac chat dinh duong trong dat d ba Tay cao han khdng dang kd so vai bd Ddng. Ngoai trir
kali tdng sd d mtic tir kha den giau (0,18 - 0,68%), thi cac chat dinh duong khac deu d muc ngheo va rat ngheo ca d tang tren va tang dudi: miin bien dgng tir 0,57 1,64%; dam tdng sd tir 0,056 - 0,086% va lan tdng sd tir 0,021 -0,054.
+ Dam Cau Hai: Cung nhu dam Thiiy Tu - Ha Trung, dat d dam Cau Hai cung rat chua (pH tir 4,12 - 4,40), ty le cat rat cao (87,9 - 90,1%);
ham lugng kali tong sd d muc tir kha den giau (0,23 - 0.52%) nhung ngheo cac dinh dudng khac ca d tang tren va tang dudi: mim bien ddng tir 1,03 - 1,59%; dam tdng sd tir 0,084 - 0,087%; ian tdng sd tir 0,036 - 0,063%.
+ Dam Lap An: Dat d day it chua (pH tir 5,33 - 5,88); cd ham lugng chat dinh dudng cao ban nhtrng viing khac thuoc lap dia ven dam pha the hien qua cac chi sd: Kali tdng sd d mirc giau (0,50 - 0,73%) ham lugfng miin. dam va Mn tdng sd deu d mirc trung binh va kha (mim: 2,17 - 2,79%, dam: 0,09 - 0,11; lan tdng s6: 0,068 - 0,15%). Thanh phan ca gidi cd ty le cat bien dong tir 80,2 - 91,9%. Nhin chung, dat d bd Ddng ciia dam tdt han dat d bd Tay, the hien d chi sd ham lugng cac chat dinh dudng trong dat cao han va ty le cat d bd Ddng tir 80,2 - 82,9%, th4p hon rat nhieu so vdi bd Tay, bien dgng tir 89,9-91.9%.
- Dat ao nuoi thiiy san ha trieu: Ao nudi thuy san ha trieu nguyen la cac bai dat bdi ngap man d ven dam pha, do ngudi dan dap de, ian pha xay dung nen, do dd ve ca ban tinh chat, dac diem ciia loai dat nay gidng nhu ciia dat ven dam pha lien ke vdi nd. Tuy nhien, do tac ddng lau dai ciia hoat ddng nudi thuy san nhu viec cay ai nen dat, bdn them vdi va thirc an du thira trong qua trinh nudi thiiy san da lam thay ddi ket cau thanh
Tap chi KHLN 2014 Phgm Ngoc DOng, 2Q14[4) phan CO gidi ciia dk. tang them dd kiem va
ham lugng cac chat dinh duang trong dat.
Kkl qua phan tich dat tai 04 khu vuc Ddng va Tay pha Tam Giang, dhm Sam - Chudn va phia Tay dam Thiiy Tu - Ha Trung da khang dinh rat ro dieu nay:
+ Ddt ao nudi thiiy san d bd Ddng ciia pha Tam Giang cd dac tinh it chua (pH tir 5.37 - 5.67); giau kali, trung binh ve ham lugng mim, dam va lan tong sd; thanh phan co gidi cd ty le cat kha thdp tir 74.8 - 76.9%. t\ le thjt va set tir 23.1 -25.2%.
+ Dat ao nudi thiiy san d bd Tay pha Tam Giang cung cd dac tinh it chua (pH tir 5,11 - 5.68); giau kali nhung ngheo dam va lan tdng sd. ham lugng miin d mirc trung binh; thanh phan CO gidi cd ty le cat kha thap tir 71,0 - 81,2%, ty le thjt va set tir 19,2 - 29,0%.
+ Dat ao nudi thiiy san d dam Sam - Chudn cd dac tinh chua (pH tir 4,44 - 5,02); giau kali, trung binh ve dam tdng sd nhung ngheo miin va lan; thanh phan ca gidi cd ty le cat tuang tu dat ven dam tir 78.9 - 86.8%. ty le thit va set tir 13,2-21.1%.
+ Dat ao nudi thiiy san d bd Ta\ dam Thiiy Tii - Ha Trung cd dac tinh chua (pH tir 4,83 - 5,13);
giau kali, trung binh ve ham lugng miin, dam va lan tdng sd.
IV. KET LUAN
(1). Dien tich DNM cd the trong rimg ciia tinh Thira Thien Hue la 2.765.Sha, trong dd viing ao nudi thiiy san ha trieu cd dien tich Ion nhdt, dkn 2.502,5ha. chilm 90,48%; tilp din la viing ven dam pha. 206.9ha, chilm 7,48%;
viing cua song cd 40,4ha. chilm 1.46% va viing ven bien la nhd nhdt. chi cd 16.0 ha.
chiem 0,57% tdng dien tich.
(2). Dua vao do man cua nudc. da phan loai DNM ciia tinh Thira Thien Hue thanli 05 viing gom: (i) Viing 1: Cd mdi trudng biln ddi chu ylu giua nudc ngpt va lg nhat, tieu bilu cho viing nay la khu vuc Dien Hai d cue bdc cua pha Tam Giang: (ii) Viing 2: Co moi trudng bien ddi chii yeu giira nudc nggt, lg nhat \ a lg \ ira, tieu bieu cho viing nay la khu vuc Sia thugc pha Tam Giang; (iii) Viing 3:
Cd mdi trudng bien ddi chu \eu giiia nuac nggt, lg nhat va lg vira va lg man, tieu bieu cho viing nay ia viing dam Cau Hai va cac khu vuc cua sdng Huong, cua sdng Bii Lu;
(iv) Viing 4: Cd mdi trudng bien ddi chu yeu giua lg vira va lg man, tieu bieu cho viing nay la cac khu vuc Thuan An, dam Sam Chudn, dam Thiiy Tu - Ha Trung thupc pha Tam Giang - Cau Hai; (v) Viing 5: C6 moi trudng bien ddi chu yeu giiia lg vira, lp man va lg qua man, tieu bieu cho viing nay la cac khu vuc ven bien Tu Hien, ven bien Lang Co va dam Lap An.
(3). DNM ciia Thira Thien Hue cd dac tinh chung la chua; thanh phan c a gidi thugc loai dat cat pha vdi ty le cat bien dgng trung binh tir 80 90%; ddt giau kali tdng so, nhung ham lugng lan, dam tdng sd va miin cd su bien dpng kha Idn, tir mirc ngheo den kha tiiy thudc tirng viing dat. Dat d cac khu vuc cua sdng. ven bien va ao nudi thiiy san giau dinh duang han dat d viing ven dam pha. Vdi tinh chat, dac diem nhu vay, DNM tai Thira Thien Hue khdng phai la loai dat thich hgp nhat ddi vai CNM, tuy nhien van cd the phat trien dugc RNM tren loai dat nay. bdi CNM cd kha nang thich nghi kha cao vdi dieu kien mdi trudng, cd the song ngay ca tren n l n ddt rat ngheo dinh duang nhu nen cat, sdi va ran san hd (Phan Nguyen Hong, 1999).
Phgm Ngoc Dung, 2014(4) Tap chi KHLN 2014
TAI LIEli THAM KHAO
I. Phan Nguyen H6ng. 1999 Rirng ngap man Viel Nam. Nxb Nong nghiep. Ha Noi
2 So Khoa hoc va Cong nghe Thira Thien Hue, 2004 Dac diem l\hi hau - thuy van linh Thira Thien Hue Nxb Thuan Hoa - Hue.
3. Le Van Khoa va cpng sy, 1996. Phirong phap phan tich dat, nuoc, phan bon, ca; tr6ng. Nxb Giao due.
4. Ton That Phap, 1993 Nghien ciru thuc vat thuy sinh o pha Tam Giang tinh Thira Thien Hu^ Luan an Pho tiSn sT Khoa hoc sinh hoc.
5 Nguyen Hai Tuat, Ngo Kim Khoi, 1996 Xu ly th6ng ke kgt qua nghien ciru thuc nghiem trong nong lam nghiep tren may tinh. Nxb. Nong nghiep, 1996.
Nguoi thdm dinh: PGS.TS. V6 Dai Hai