Tgp chi Khoa bgc Tnrdng Dgi hoc Can Tho Phan A Khoa hgc Tu nbien. Congnghe vd Moi tnr&ng- 29 (2013): 51-5~
Tap chl Khoa hoc Tru'cfng Dai hoc Can Thd website: sj.ctu.edu.vn
DANH GIA SU* 6 NHIEM TREN RACH SANG TRANG QUA SU* PHAN BO CUA DONG VAT DAY
Duang Trf Dung' va Huynh Thi Quynh Nhu
' Khoa Mdi trudng & Tdi nguyen Thiin nhien, Trudng Dgi hoc Can Tha Thdng tin chung:
Ngdy nhdn-01/05/2013 Ngdy chdp nhgn: 24/12/2013 Title:
Assessment of the pollution on Sang Trang canal bases on the distribution ofbenlhic invertebrates
Tdkhda:
Dgng vgt ddy, 6 nhiem nudc, ASPT
Keywords:
Benthic invertebrates, M'ater pollution, ASPT
ABSTRACT
The study on the distribution ofbenlhic invertebrates on the Sang Trang canal was carried out twice (the end of rain season and mid of drain season) to evaluate the water quality changes according to the pollution caused by waste water of the Can Tho industrial zone. Twenty-eight benthic invertebrate species were found, belonging to 15 families.
Amongst those, Bivalve and Gastropod were of rich species and the worm Limnodrilus hoffineisteri appeared on each sampling position with high density. The findings showed that the organic matter led to continuous pollution of the Sang Trang canal. The pollution on the canal was characterized from fair to serious levels (low ASPT score).
TOM TAT
Viic nghiin cuu suphdn bd cua dgng vgt day trin rgch Sang Trdng dugc tien hdnh hai dot vdo cudi miia mua vd giira miia khd nhdm ddnh gid su thay doi chat lugng nudc tren thuy vuc bi d nhiem do nudc thai khu cdng nghiip d Cdn Tha. Kit qud da phdt hiin dugc 28 lodi dgng vgt ddy thuoc 15 ho, trong do ldp Bivalvia vd Gastropoda cd sd lodi nhiiu nhdt Lodi Limnodrilus hoffmeisteri ludn xudt hiin tren cdc diim khdo sdt vdi mat do cao, the hiin tinh trgng d nhiim hiru ca ludn diin ra d rgch Sang Trdng.
Diem sd ASPT thdp the hiin mdi trudng tren rgch Sang Trdng bi d nhiim tif muc do khd cho den ndng.
1 MO DAU
Theo Sd Tai nguyin va Mdi trudng Thinh phd Cdn Tha (2011), chdt lugng nudc mat trin sdng Hdu bi d nhilm chat hiiu ca vdi cdc thong sd hda hpc khdng dat QCVN 08:2008/BTNMT va cd khuynh hudng ngiy cdng gia tang. Hai khu cong nghiep ldn nhdt tgi Thdnh phd Cdn Tho la Tra ndc 1 vd Tri ndc II ndm dpe theo sdng Hdu chua co hi thing xir ly nudc thai tip trung. tdng khdi lugng nudc thii tir hai khu cdng nghiep la han 12.000 ni-^/ngiy xa qua 17 cdng thoat nudc fryc tilp vdo sdng cho nen cd khi nang gay d nhiira nudc trong he thing sdng. kenh rgch xung quanh, inh hudng true tiip den cupc sdng ciia ngudi ddn noi do. Va
rgch Sang Tring noi tilp nhan tryc tiep ngudn nudc thai tii khu cdng nghiep Tra Noc I vi 11 Id mdt frong nhirng diem ndng ve sy d nhiem mdi frudng nudc.
Van ds sir dung sinh hpc de giam sal chdt lugng nudc ngpt da dugc de cap it nhieu frong 10 nam trd Igi ddy d nudc ta. Tuy nhiin, kfai Nguyen Xuan Quynfa vd ctv. (2001) xiy dyng he thdng linh diim BMWP^'^^ va khda dinh logi din hp cac nhdm dpng vat khdng xuong sdng cd ldn nudc ngpt thudng gap thi that sy bat ddu ung dung rdng rai quj' frinfa gidra sdt ehit lugng nudc ciia cac thuy vyc nudc ngpt Viet Nara. Phuang phip nay di dugc lien hanh d nhilu song ngdi, nd cho thiy day
Tgp chi Kboa bgc Tnrang Dgi bgc Cdn Tha Phin A: Kboa hgc Tu nhien. Cong nglie vo Moi iru&ng- 29 (2013): 51-^
Id phuong phdp phii hgp vdi dieu kiln nudc ta (Nguyen Vdn Khdnh vd ctv., 2007).
Ve tieu chuan hay quy chuan radi trudng cua bp Tai nguyen vi Mdi trudng hiln nay chua cd tieu chuin sinh hpc di dinh gia chat lugng nguon nudc mgt do do cin co nhiing nghiin ciiu frln nhilu khu vyc dl xdy dyng mdt hp thdng chi sd sinh hpc dimg dl ddnfa gid cfait lupng nudc phu hgp cho timg vimg. Viec dp dyng quan frdc sinh hpc d Viet Nam da thu dugc nhtrng thanh tyu budc ddu vd dang dugc chii y (Hoang Dinh Tmng vd ctv.. 2011).
Mac dii da cd nhilu kit qua quan frac ve chat lugng nudc frln he thdng kenh rgch Can Tho nhung da phdn tap trung vao cdc chi tllu hoa hpc va ly hpc, cd vii nghiin ciiu ve dpng vat day de danh gia sy 6 nhilm ciia thiiy vyc nhung chua xac Bang 1: Dac diem ciia tiing vj tri khao sat tren rach
dinh dugc cic lodi sinh vit chi tfai cho su d nhilm dd vi viy viec nghien ciiu sy phin bd ciia dpng vat day tren rach Sang Trdng dugc thyc hien nhim tira hiiu loai d nfailm nudc mdt tai rgcfa Sang Trii^
thdng qua sy phdn bd cua dpng vit diy tren do.
2 PHU'ONG PHAP NGHIEN CUtJ 2.1 Tfadi gian va dia diem ngfaien cihi - Chu ky thu miu: viec khdo sdt dugc tiin hdnh vio 2 lan, lin 1 vio thdng 12 nam 2011 vao cuii miia mua lii va lin 2 vao giiia miia kho (03/2012). Thu raau dugc tiin hanh Iiic triiu kilt frong thing.
Tren rach Sang Trdng chpn 14 vi frf dl khdo sat. ddc diira ciia 14 vi fri duge trinfa bay qua Bdng I.
Sang Trang Vj tri
(Kfhifu)
Tpa dp
(UTM, 48P) Mo ta 0577201
1117938 Dau rach Sang Trdng, trao ddi nudc tryc tilp vdi sdng Hgu.
0577322
1117937 Diu rach Sang Tring tilp vdi song Hdu 0577201
1117825 Cdng thii tip trung ciia cac co sd sdn xudt 0576878
1117525 Nga ba chia thdnh hai nhdnh Sang Trang 1 va Sang Trang 2.
0576895
1116925 Cdng thii tgp trung ciia cic ca sd KCN Trd Ndc I.
0576924
1116655 Cdng thdi tap trung ciia cic co sd KCN Trd Ndc I.
0576507
1117521 Cdng thai tap frung ciia cac co sd KCN Tra Ndc 1.
0576471 1117510
Cdng thai tap trung ciia cdc co sd sin xudt, cdng bj che lip bcri say.
0576306 1117364
Dau eac rach nho ndi vdi rach Sang Trang; c6 su xa thai ciia cac CO sd sdn xuit.
0576031
11I722I Ddu cac rach nhd ndi vdi rach Sang Trang.
0575933
1117152 Dau cac rach nhd noi vdi rach Sang Trang.
0575724
1116522 Khu dan cu va chg nhd.
0575362
1116409 Dau cac rach nhd ndi vdi rach Sang Trdng.
0574904
1116210 Nga ba cua Sang Trdng 2.
2.2 Phuong tiln va pfauong pfaap nghien cuu Dimg gau day Petersen cd dien tich 0,021 m^ di thu mau. logi bo bdt bim vi rac tai hiln ttudng qua
sang ddy cd raat ludi 0,5 ram rdi cho mau vdo bpc ny-lon, cd dinh formol vdi ndng dp tir 8-10% rdi mang vi phdng thi nghiem de phin lich.
Tap chi Khoa hgc Tnrang Dgi hoc Can Tlia Phan A: Khoa hoc Tu nhiin. Cong ngh? vd Moi tnrang: 29 (2013): 3I-:
2.3 Phirong phap phan tich mlu Phdn tt'ch dinh tinh: Mau dugc quan sit dudi kinfa lup vd kinh failn vi va dya vdo tdi lieu phdn logi su dung Id "Dinh loai ddng vdt khdng xuong sdng nudc nggt Bac Viet Nam" ciia Dang Nggc Thanh, Thii Trdn Bdi va Pham Vdn Miln (1980) vi "Aquatic insects of Caliofomia" cua Robert L (1997).
Phan tich dinh lutpig
Mdu sau khi phdn tich se dugc ldm khd bdng gidy tissue rdi dim sd lugng va cdn frgng lugng.
Sinh lupng ddng vdt ddy dupe tinh theo cdng thirc:
D = — Trong dd:
D: mat dd (cd the/m-) faay kfadi luang (g/ra^).
X: sd lugng hay khdi lugng dpng vit diy.
S: diln tich miu thu dugc. Vdi S=n.d (n: sd lugng giu da thu; d: di|n fr'ch raiing giu.
2.4 Pfauong phap xu ly so lieu
Ddnh gid chdt lugng nudc dya vio chi sd quan
^ ° T n Cuoi mua mua IC J „ • Giiia mua khd 14
12 -
':, 8 n
6
JUL
frde sinh hoc BMWP^'^ (Biological Monitoring Working Party) va bing mire dp d nfaiem ASPT (Average Score Per Taxon) (Nguyen Xudn Quynfa v<7cn'.,2004).
Chi sd da dgng cua dpng vat day Shaimon- Weiner (H') dugc xac dinh theo cdng thirc:
H'= -Xpi-lnpi vdi pi = nj/N. Trong do: n, li sd cd the lodi thu i vd N la tdng sd ci tfal cua ddng vat ddy frong mdu.
3 KET QUA VA THAO LUAN 3.1 Thanh phdn loai va su biin dpng thanh phan loai dpng vat diy tren racfa Sang TrSng qua hai mua
Qua kit qui khio sit frln 14 diera d rgch Sang Tring di ghi nfain dupe 28 loai dpng vat diy tfaudc 6 Idp. Ldp Gasfropoda cd 10 loii chiira 35% trong tdng sd loai phit hiln dugc, tilp theo la ldp Bivalvia cd 8 loai chilm 28%i, ldp Insecta cd 5 loii cfaiim 18%. ldp Oligochaeta cd 3 loai chilm 11%, Idp Polychaeta vi Crustacea cfai chilm 4% vdi I loii cho radi Idp.
Sy biln ddng thanh phdn lo^ giiia 2 ldn khdo sit dugc frinh bdy qua Hinh I.
PI P2 P3 P4 P5 P6 P7 P8 P9 PIO P l l P12 P13 P14 Cac \i tri khao sat
Hinh 1: Tfaanfa pfaan loai dpng vat day giira hai miia ir racfa Sang Trang Hinh 1 cho thdy hdu hit cdc vi fri kfaio sat sd
loai ddng vit day vdo cuoi mua mua ed khuynh hudn" cao hon sd lodi giiia miia khd. Vdo miia khd nin day vd chit lugng mdi trudng nudc da thay ddi lam tha> ddi thanfa phdn ddng vdt ddy. va cd khuynh hudng giam ddn. 3 lodi khdng tira tfaiy vio dgt miia khd la Corbicula tenuis. Corbicula
morelefiana vi I loai thupc hp Chironomidae, nhung lgi cd nhiing loii ua hthi co xuat hiln thudc hp Unionidae vi Mylitidae Id Mecetopoda siliquosa, Nodularia sp va Limnopema siamensis.
Cdc vi fri sdu frong rgch la Pll va P14 cd sd loai bien ddng ldn, vio raiia kho cdc loai ua
Tap chi Khoa hgc Tnr&ng Dgi hgc Cdn Tho
1 Phan A: Kboa bgc Tu nhien. Cong nghi vd Mdi tnt&ng: 29 (2013): 51-57 <
nudc sgcfa ihudc hg Corbiculidae Id Corbicula moreletiana. Corbicula baudoni, Corbicula castanea. mdt di nhung nudc trieu di sdu vao frong mang vio thim loai giun nhieu to Id Namalycasiis longiciris.
Thinh phin cdc lodi ddng vdt day o rach Sang Trdng phdn bd kfadng diu gitra cdc diim nghien ciiu (lir PI din P14), cdc loii ddng vdt ddy thudng tap trung d nhiing noi tilp giip vdi ngudn nudc sdng Hdu nhu d vi tri PI vd P2 vdi thdnh phdn khd phong phu. Vi tri P5 vd P6 noi nhdn nhiiu chit thdi do day li cdng thii tgp trung cua khu cdng nghiep Tri Ndc I nin tfadnfa phan loai d diy thip hon so vdi cic vi fri khio sit khae.
Cd mdt sd loii phan bd rpng nhu Bellamya filosa va An^ulyagra polyzonala thupc hp
Viviparidae xudt hien hdu nhu d tit ci cac vj tri thu raau qua 2 dgt thu mau vdi mit dp khd cao.
Mpt sd loii c6 phgra vi phan bd hep, chi bit gap tai mpt diim nghiin ciiu vi vdi mat dp thdp nhu Digoniostoma siamense thudc hp Bithyniidae.
Nhora giun nhilu to tuy cd ngudn gdc biln nhung 60000
50000
•Sp 40000
<o- 30000
• 20000
:4
ciing dugc phdt hien d ddy do sy di nhgp ciia thiiy sinh vit bien vao ndi dia (Ding Ngpc Thanh vo ctv., 2002).
3.2 Biin d$ng ve mgt dg va sinh khoi dpng vdt day tren rgch Sang Trdng
3 2.1 Biin dgng mat dg dgng vdt ddy tren rgch Sang Trdng qua hai mita
Qua Hinh 2 cho thiy mat dp dpng vat ddy bien dpng giira hai miia rdt Idn, kfauynh hudng giira dan tir miia mua sang miia khd. Mat dp ddng v^t day gidra chii yiu do sy gidm ragnh sd lupng ci thi ciia cdc loii giun it la Limnodrilus hoffineisteri vi Branchyura sowebyii ciia hp Tubificidae nhu d vj fri P3 biin dpng rail dp dpng vdt diy li thay ro nhit, sd lugng ci thi vdo miia khd chi bdng kfaoing 1% so vdi mua mua vdi tdng mgt dp ddng vgt day vdo raiia mua la 53410 ci thl/m^ vi vao miia khi li 695 ca thl/m^ trong dd mat dp ddng vdt ddy ciia loai Limnodrilus hoffineisteri Id 47285 ci thi/m- vio mua raua bj giim cdn 362 ca the/m^ vao miia khd, lodi Branchyura sowebyii la 5667 cd thl/m-^
vio raiia mua bi giam cdn 114 ca thi/ra-.
• Cuoi mua mua
• Gitra mua kho
Lik. kri.n.^.
PI P2 P3 P4 P5 P6 P7 P8 P9 PIG P l l P12 P13 P14 Cac vi tri khao sat
Hinfa 2: Bien dpng mat do dpng vat day giiia mua mua va miia kfao d rach Sang Trdng Ci vj fri P13 va PI4 ting mat dp ci tfai vdo miia
kfad cd tfal do nen diy da thich hgp cho cac loai ddng vgt day phdt friln hon. hoac do sau miia lu thi raOt phan dpng vgt day lir nhiing vi fri khde da frdi dat vi diy. Theo Dang Ngpc Thanh (1974) thi si lugng dpng vgt diy sdng phy thudc rdt nhiiu vao raiia nudc lu. ldm xdo frpn nen ddy vi so lupng ciia sinfa vit diy sdng cung biln ddi theo timg loai sinh
canfa va timg thdi gian, phy thupc vio chi dp nudc chay vi myc nudc.
3.2.2 Biin dgng sinh khdi dgng vgt ddy trin rgch Sang Trdng qua hai mua
_Qua Hinh 3 cho tfaay sinh khii dpng vgt day biln dpng mgnh giiia hai miia tgi timg vj tri khio sdt va thi hiln rd ret la vi fri P4 vd PI 1.
54
Tap chi Khoa hgc Tnrang Dgi hgc Cdn Tha Phdn.4: Klioa hoc Tunhien Congnghe -.a Moi tnrang- 29l2013i. -•>/-."
2000 1500 - 1000
"Cuoi mua mua -Giira mua kho
500
PI P2 P3 P4 P5 P6 P7 P8 P9 PIG P l l P12 P13 P14 Cac vi tri khao sat
Hinh 3: Bien ddng sinh kfaoi dpng vat day giua miia mira va mda kho d racb Sang Trang Trong 14 vi fri khdo sil thi cac vi fri PI, P2. P4
vd P7 cd sinh khdi tang lln vdo miia khd so vdi miia raua, cac \'i tri cdn lai suih khdi ddng vit diy giam di vao miia khd.
Cic vi tri gin ciia cdng ciia kfau cdng nghiip co sinh khdi thap va biln ddng ldn, d vi fri P5 sinfa khdi vio miia raua Id 37,562 g/ra- va da giam sinh khdi cdn 5,971 g/m^ vdo miia kfad (gidm khoang 71% sinh khoi ddng vat diy). dd Id do sy gidm di cdc lodi nfauyin thi nhu Assiminea brevicula thudc hp Assiminea vd Melanoides tuberculatus tfaupe hp Thiaridae. Theo Dang Nggc Thanh (1974) logi nudc thai do cdng nghiep dd ra thi rat phiic tap vl thinh phin, frong cac tic hgi thi tic hai ca hpc do lugng phdn rac. chit vin. chit sgi cd rit nhilu frong nudc thai, phu kin ca nin day thiiy vyc nen lim thiiy sinh vdt d nen day khdng the phdt frien dugc. Cling theo Dang Ngpc Thanh (1974) thi nlu khdng tira thiy dugc logi nin da\ tfaiefa hgp.
logi sinh \ at diy iy cd thi bi giim sd lugng hodc bi tieu diet.
Cic loii nhuyin Ihl thupc hp Viviparidae nhu .Angulyagra polyzonala, Bellamya filoscr, cic loai thupc hp hen Corbiculidae nhu Corbicula baudoni.
Corbicula castanea da anh hudng den tdng sinh khdi. 6 vi tri P4 co sinh kfadi biln dpng cao nhat.
vao cudi raiia mua li 39,333 g/m^ va mua khd 472,105 g/m-. sy gia tang sinh khdi do cdc loai thupc fap Corbiculidae dd ting vl sd lupng ca the v i khdi lupng mdi cd the. rieng loai Corbicula castanea da cd sinh khdi Ii 18,867 g/m~ vao mua mua vd 220.619 g/m- vdo miia khd da tdng han 10 lin.
3.3 Chi sd da dgng Shannon-Weiner (H*) Chi sd da dang (H') cua ddng vat day frln rach Sang Trang vio cudi mua mua co khoang dao ddng tir 0,036 din 1,713 vi giira miia khd Id 0.035 din 1.445.
P6 P7 P8 P9 PIO P l l P12 P13 P14 Cac vi tri khao sal
Hinfa 4: Chi sd da dgng ciia dpng vgt day qua cic \ | tri khao sat tren rach Sang Trdn"
55
Tap cbi Khoa hgc Tnr&ng Dgi hoc Cdn Tha Phin A Khoa hgc Tu nbien. Cong ngbe va .Mdi Inrang: 29 (2013): 5J-57 Nhin chung, tinh da dang ddng vdt day d cudi
miia mua thip do 8/14 diim (hon 50% vi tri khdo sdt) di cd H'<1: con vdo giua raiia khd thi cd din hon 70% vi tri kfado sdt cd H"<l nin giiia raiia khd thi tinfa da dang ddng vdt diy ciing thdp vd ngdy cdng kem da dang tgi cdc vi tri kfado sit; dieu niy ciing ndi len miic dp ngheo nan thinh phdn loii d khu vyc dang bi 6 nhiira (Le Vin Khoa vd ctv., 2007).
Theo Ding Ngpc Thanh (2002) thi chi sd da dgng thay doi theo diiu kiln ty nhien cOa thuy vyc.
Mdt khic, vdi tgp tinh mdt sd loii thay tfal nhau phit friln uu tfal ve sd lugng theo timg thdi diim cd the ldm giira chi so da dgng. dieu dd cd nghia Ii frong rapt mdi trudng mac dii khdng bi d nfailm nhung van cd chi sd da dgng tfaip.
Chl so da dgng (H') ludn biin dOng gi tta hai mOa vi giiia cac diem khao sit tgi rgch Sang Tring, mac dil cd ciing sd lodi nfaung chi so da dang van cd sy khdc bill nhu ba vj tri PI, P9 vd P12 vio cudi miia raua chi sd da dang cd gii tri ldn lugt ta 1.466, 0.518 vd 1,512 nfaung cimg sd loai li 15.
Ben canh do. rapt sd diim cd sd loai kfadc nhau nhung chi sd da dang van bing nfaau nfau d vj fri P2 vio hai miia. Cfai sd da dang cao nlu raSi ca thi thuOc mpt loai rieng re vi cd chi so da dgng thap khi tdt ci thupc vl rapt lodi. Tir do cho thiy, chi so da dgng khdng phdi chi phy thudc vdo thanh phan sd lugng loai mi cd sd lugng ci thi vd xdc sudt xuit fai|n cua cdc ci thi frong mdi loai.
Bang 2: Xep loai chat lirgng nirdc theo he thong Weiner
Do cdc diim kfaao sdt qua hai dgt deu cd gid fri H"<2 nin cd tfai ddnh gid mdi trudng nude tgi thiiy vyc thudng xuyln nam frong tinh trang mdi trudng tir rit d nhiem (P5 vd P6 la 2 diim cd H' nhd nfadt) cfao din d nhilm. Nfaung theo D§ng Ngpc Thanfa (2002) khi sii dung chi s6 da dang cua bit ki qudn xi sinfa vat nao cin thara khdo cic gii tri vi sinfa vdt lugng vi loai hinh thiiy vyc. Mpt vin dl quan frpng khi sii dung chi si da dgng Ii phdi thu dupe vit mdu khd diy dii v i kfadefa quan. Niu phuong tiln thu miu khong tdt thi gid frj tinh dugc ciia chi s i da dang bj sai sdt nhieu. Dilu dd inh hudng khdng nfad cho ddnfa gid cfadt lugng mdi frudng.
3.4 fianh gia d nhiim bdng h i thing tinh diim BMWP^'"
Qua Bing 2 cho thiy cdc diim khao sit deu co tinh frgng 6 nhiem tir khi d nhilm din 6 nhilm ngng khi xep loai chat lugng nudc theo BMWP- ASPT. Diim si BMWP va ASPT Id tuong quan thuin nin vdi diim BMWP cao thi ASPT cung cao; nfaung BMWP cd gii fri bdng 1 thi ASPT cung bing I. Cd 6 diem (PI, P2, P3, P7, P8 va Pll) frong dgt thu mdu dgt 2 cd chi sd ASPT cao hon dgt 1 chimg td rairc dp d nhilm da cd sy thay ddi giiia hai mua, chuyin dang d nfailm ngng sang dang kfai d nhiem chirng td tinh trgng 6 nfaiem cua giiia miia khd da cd chuyin biin tuong dii tit tai mpt vai dja diera cy thi nhung mdi truongnudc tai thiiy vyc cung khdng khd quan han do diera so van thdp. Cac diim cdn lgi thi chat lugng nudc hoan todn khdng thay doi giiia hai raiia.
BMWP (Viet Nam) va chi so da dgng Shannon- V( tri
thu mau PI P2 P3 P4 P5 P6 P7 P8 P9 PIO Pil PI2 PI3 PI4
BMWP"^T vao 0 nhiera ngng 6 nhilm ndng 6 nhiera ndng 0 nhiera ndng 6 nhiera ndng 6 nhiira ngng 6 nhilm ndng O nhilm ning 6 nhilm ning 6 nhiem ndng O nhilm ning Kha d nhiem 6 nhiem ndng Kha d nhiem
j _ ;
CUOI mua mua H' O nhiem Rat 6 nhiem Rit 6 nhiira Rat 6 nhiera Rit 6 nhiem Rdt 6 nhiem 6 nfailm Rat 6 nhiem Rdt 6 nhiem 6 nhilm Rat d nhiim 0 nhiem 0 nfaiem 0 nhiera
Vao BMWP^ '^^
Khi 6 nhiem Khd 6 nhiem 6 nhilm ngng O nhiem nang 0 nhilm ngng O nhiem ngng Khd d nhiem Khd d nhiira 0 nhiem ning 0 nhiem ning Khi 6 nhilm Khi 6 nhilm 0 nhiem ning Khi d nfaiem
giua mita khd H' 0 nhiem Rit d nhiera 0 nhiira Rit d nhiera Rat d nhilm Rdt d nhilm Rdt d nhilm Rdt d nhilm Rat d nhiem 0 nhiem Rit d nhiera 0 nhiera Rdt d nhilm Rdt d nhiira Qua Bang 2 cho thay khi sii dyng chi so da
dang Shannon-Weiner (H') \a h | thdng tinh diim SMW?""'^^ vd ASPT thi nhin chung ci 2 chua thiy
dugc sy tuong ddng vdi nhau. Chi sd da dgng Shannon-Weiner (H') danh gii thiiy vyc tir rat 6 nhilm cho den d nhilm. cdn he thdng tinh diem
Tgp chi Khoa hgc Tru&ng Dgi bgc Cdn Tho Phdn A: Kboa hgc Tu nbien. Cong ngh? vd Moi tnr&ng- 29 (2013) - 51-57 BMWP^'JE'" va ASPT thi kit ludn thuy vyc tir khd d
nhiem din d nhilm ngng. Nhung tgi mdt sd vi tri nhu PI, P7 vd P13 vdo cudi miia mua vd cac vi tri P3 vd PIO vao giiia raiia mua tfal BMWP^'^^ ddnfa gii chdt lugng mdi trudng tllu cyc han H' vi ciing cd nhiing vi fri nhu P2, P7, P8, P l l va P14 thi BMWP^'^''" ddnh gid chit lugng mdi truong khdch quan ban H'.
4 KET LU^N VA DE XUAT 4.1 Ket luan
Qua hai dgt khao sdt da pfaat fai|n dugc 28 loai dpng vdt diy thupc 15 hp tgi rach Sang Trdng trong dd Idp Bivalvia vd Gasfropoda co sd lodi nhieu nhat.
Tat ci cic diem khao sat diu xuat hiln loii Limnodrilus hoffineisteri vdi mat dp cao, nhat la vdo cudi miia mua cho thiy tinh frang d nhilm huu CO ludn dien ra d rach Sang Tring.
Trong ting sd 15 hp da phat hi?n dugc thi 9 hp cd frong he thdng tinh diim BMWP^'^^. Qua diim sd ASPT thap the hien mdi trudng frln rgch Sang Trdng bi 6 nhiem tir mirc dp khd eho din nang.
4.2 De xuat
Cd thi sir dung ti l | lodi uu thi ciia loai Limnodrilus hoffmeisteri de danh gid d nhiem nhung phdi xem loai hinh thiiy vyc vi cac ylu td tic dpng.
- Cin tang tin suit thu mlu dl tang xdc suit bat ggp cdc loai dpng vdl ddy nham danh gia ddy diJ hon cdc lodi xudt hiln thdi gian ngin trong thiiy vyc.
TAI LIEU THAM KHAO
1. Ll Van Khoa, Nguyin Xudn Quynh va Nguyin Quoc Vi|t. 2007. Chi thi sinh hpc moi trudng. Nhd xuit ban Gido due. Hd Ndi.
2. Nguyen Vin Khdnfa, Phgra Van Hipp. Phan Thi Mai vd Ll Thi Qui. 2007. Su dung dpng vat khdng xuong song cd Idn dinh gii chit lugng nudc bi mit tgi canh ding Xuan Thieu.
phuong Hoa Hiep, qudn Liln Chilu, thanh phd Da Ndng. Trudng Dgi hpc Di Ning.
3. Nguyin Xuan Quynh, 2001. Dinh loai cic nhdm ddng vdl khdng xuong sdng nudc nggt thudng gdp d Viet Nam, NXB Dal hpc Quic gia Ha Ndi.
4. Sd Tdi nguyin vd Mdi frudng. 2011. Bdo cdo hiln frang mdi trudng Thanh phd Can Tha 2010.
5. Dang Ngpc Thanh, Hd Thanh Hii, Duong Diic Tiin vd Mai Dinh Yin. 2002. Thuy sinh hpc cic thiiy vyc nudc ngpt. Nlid xudt bdn Khoa hpc vi Ky thuat. Ha Ndi.
6. Dgng Ngpc Thanh, Thdi Tran Bdi va Pham Van Mien. 1980. Dinh loai ddng vat khdng xuong song nudc ngpt Bac Viet Nam. Nha xuit ban Khoa hpc vi Ky thugt. Ha Ndi.
7. Ding Ngpc Thanfa. 1974. Thily sinfa fapc dgi cuong. Nha xudt ban dai hpc va trung hgc chuyin nghlpp. Ha Npi.
8. Hoang Dinh Trung, Vd Vdn PhQ va Ll Thi Miln Ngpc. 2011. Da dgng thinh phin lodi dpng vat khong xuong sdng cd ldn vd chdt lugng nudc mat d sdng Huong. Tap chi Nghiin ciiu vd Phdt triln, frang 89-95.
