88 Tap chi Nghien cffu va Phat trien, sd 1 (78) 2010 HIEN TRANG THAM THlJC VAT NGAP MAN 6 VUNG DAT NGAP Nl/dc TAM GIANG CAU HAI, TINH THl/A THIEN HUE Hoang Cong Tin, Mai Van Pho, Ton That Phap'''' I Dat[.]
88 Tap chi Nghien cffu va Phat trien, sd (78) 2010 HIEN TRANG THAM THlJC VAT NGAP MAN VUNG DAT NGAP Nl/dc TAM GIANG-CAU HAI, TINH THl/A THIEN HUE Hoang Cong Tin, Mai Van Pho, Ton That Phap' I Dat v a n de Vung da't ngap nffde (DNN) Tam Giang-Cau Hai d Thffa Thien Hue vdi dien tich han 21.600ha la mdt nhffng dam pha ldn n h a t Ddng Nam A Trong dd, Ru Cha la mdt mdng rii^g ngap man n h a t edn lai d pha cd vai trd ldn viec ehe chdn gid bao eho vung Hffffng Phong eung nhff gdp phan tri ngudn lgi va da dang sinh hge eua vung dam phd Tuy nhien, hien eac hoat ddng canh tae ndng nghiep, xay ddp de ngan man, phat trien nuoi trdng thuy san va tai bie'n thien nhien da va dang la eac tae nhan de dga de'n tham thffc vat ngap man (TVNM) Vi vay, viec danh gia mgt each toan dien ve eau true eua tham thffc vat ngap man, xae dinh dac diem phan bo lam ca sd cho viec dinh hffdng ehien Iffgc quan ly vd quy hoach tham TVNM, nham bao tdn va tang kha nang bdo ve cua vung trffdc cae tac ddng eua bie'n ddi hau la mgt van de cap thie't dang dffge quan tam ldn hien II Phtfcfng p h a p n g h i e n cii'u 2.1 Ddi tiiOng vd dia diem nghien ciHu Tham thffc vat ngap man d vung DNN xa Hffang Phong, huyen Hffffng Tra, thudc he thong dam phd ven bien tinh Thffa Thien Hue' (TTH) (Hinh 1) 2.2 Ddc diem khu viic nghien cdtu Hffffng Phong la mdt xa ddng bang ven dam pha thude huyen Hffang Tra, each phd" Hue khoang 12km Dia gidi hanh ehinh cua xa dffgc bao quanh bdi hai sdng la sdng Hffffng, song Kim Ddi va mgt mat giap phd Tam Giang Dia ban xa Hffdng Phong nam tga tff 16°32'41,04"-16°35'6,27" vT bac va 107°34'30,06"107°37'45,52" kinh ddng vdi tdng dien tich da't tff nhien 15,7km2, vdi gan 10,34km ehieu dai dffdng bd ven pha thudc dia ban hai thdn Thuan Hda va Van Quat Ddng Day la hai thdn ndm phia bdc cua xa, tie'p giap vdi pha Tam Giang doan ddi dien vdi cda bien Thuan An Xa Hffang Phong, huyen Hffang Tra thude tieu vung hau la phan vung hau tinh Thffa Thien Hue Vung ed nhiet dd'trung binh nam tff 24-25,2°C, tong nhiet dp tff 8.700-9.200°C, tong so gid ndng tren 1.900 gid/nam, nhiet thap n h a t ed the xud'ng dffdi 10°C, eao nha't ed the len tdi 41°C Tdng lffgng mffa tha'p nha't tinh, tff 2.600-2.800mm, tff thang den thdng dffdi 800mm Dp am trung binh cung tha'p nha't tinh, tff • Trffdng Dai hpc Khoa hpc Hue Tap chi Nghien cffu va Phat trien, sd (78) 2010 89 Hinh Ban dja ban nghien cffu 83-84% va thieu am thdng, tff thang de'n thang Day la vung nhay cam thffdng chiu dnh hffdng manh cua gid bao, lu lut, han han va gid tay kho ndng 2.3 Phiicfng phdp nghien cvCu Cac tff lieu va phffffng phap nghien cffu thffc dia truyen tho'ng cung nhff cdng nghe mdi (vien tham va GIS) da dffgc ket hgp sd dung nghien cffu tham TVNM ven bien nhff sau: i Khdo sdt dieu tra, thu mdu phuc vu ddnh gid hien trgng thdm TVNM theo he thd'ng tuye'n va d tieu chuan (OTC) lOxlOm theo Thdi Van Trffng (1978), Nguyen NghTa Thin (1997, 2007) va Phan Nguyen Hdng (2003) Xac dinh vi tri, so loai va sd lffffng cay mdi OTC Do dffdng kinh tdn cay, dffdng kinh than ngang ngffe (1,3m), do cao vut nggn bdng thffdc va may ehieu cao ii Phdn tich ddnh gid thdm thUc vgt: Dinh loai theo phffffng phdp so sanh hinh thai bdng cae tai lieu ehinh: Pham Hoang Hg (2001), Phan Nguyen Hdng (2003), FAQ (2007) vd phan tich danh gia thdm thffc vat theo Mabinay & Magrita (2003), Huy (2005), Kathiresan (2007) gdm cae chi tieu: Mat trung binh, dd thffdng gap (tan sd' xua't hien), ffu the' tffang ddi va dien tich tiet dien than 90 Tap chi Nghien cffu va Phat trien, sd (78) 2010 Hi Ung dung vien thdm vd GIS xdy dUng bdn phdn bd dffac thffc hien dffa tren bd dnh vidn tham ALOS-AVNIR (chup 28/5/2008) dp phan giai 10m Ket qua giai doan xay dffng ban dd phan bd' dffgc chuyen sang dang bitmap va lffu trff ban dd chuyen de ve sff phan bd' eiia thdm thffc vat ngap man eho dia ban nghien cffu.**' iv Phuang phdp nghien cdu cd sU tham gia cua cgng dong dia phuang (Participatory Rural Appraisal-PRA): Gdm cae edng cu PRA nhff thdng tin thff cap (Secondary data): Thu thap cac van ban, eac bao cao khoa hge, eac sd lieu tho'ng ke, ban dd lien quan de'n sii dung va quy hoach dat cua xa Hffffng Phong, phdng van ban eau true (Semi-structure interviews), lap ban dd tai nguyen (Resources mapping), dieu tra theo tuyen (Transect line) va hgp tde vdi chinh quyen dia phffang de tim hieu eac dac diem ba't thffdng va sff tde ddng ciia bie'n ddi hau len tham TVNM eung nhff dinh hffdng sd dung va phdt trien kinh te cae vung sinh thai quan trgng d xa Hffang Phong III Ket qua n g h i e n ciJu 3.1 Cau true thdnh phdn lodi TVNM ' Qua ke't qua nghien cufu da xac dinh dffge 16 loai TVNM thugc 16 chi va 14 hg d vung DNN xa Hffang Phong Trong dd, da bd sung them'10 loai cho danh luc he TVNM d vung dam phd ven bien tinh Thffa Thien Hue (Bang 1) Thanh phan loai TVNM dffge chia lam nhdm: Nhdm TVNM chinh thffc ed lodi (chiem 37,50% tdng so' loai) va nhdm thffc vat gia nhap rffng ngap man ed 10 loai (ehie'm 62,50% tdng so' loai) Mae dau t h a n h phan loai khdng phong phu nhffng vai trd eiia thdm TVNM khong nhffng cd y nghia ve mat sinh thai ma cdn cd gia tri dd'i vdi cdng ddng eff dan thdn Thuan Hda viee phdng t r a n h thien tai hang nam Bdng Danh luc thffc vat ngap man d vung DNN xa Hffang Phong (Sdp xep theo Brummit, 1992) ,, , ; •• TT (1) 1 2 Ten khoa hoc (2) POLYPODIOPHYTA PTERIDACEAE Arcostichum aureum L MAGNOLIOPHYTA MAGNOLIOPSIDA ACANTHACEAE Acanthus ilicifolius L BIGNONIACEAE Ten Vi^t Nam (3) Nganh Dffdng xi Hp Cd seo ga Rang bien, Rau mop Nganh Ngpc lan Ldp la mam , Hp ro ro gai Hp Quao ' • Dang song Nhom TVC) (4) (5) C MS Bu MS Nguon anh vien tham ALOS-AVNIR (10m) sff dung de giai doan che phu cua TVNM dffpc cung cap bdi dff an "Quan trac cac he sinh thii ven bien Viet Nam" Cd quan tham hiem vu tru Nhat Ban (JAXA) tai trd thong qua Vien Hai dffPng hpc Nha Trang Tap the tac gia xin ehan cam Pn sff ho trp ngudn tff lieu gia trj Tap chi Nghien cffu va Phat trien, sd (78) 2010 (2) (1) 4 5 6 7 8 9 10 10 11 11 12 13 12 14 13 15 14 16 Dolichandrone spathacea (L.f.) K.Sehum CHENOPODRACEAE Suaeda maritime (L.) Dum CONVOLVULACEAE Ipomoea pes-capre (L.) Sweet EUPHORBIACEAE Excoecaria agallocha L FABACEAE Derris trifolia (Benth) Barker Canavalia maritima Thouars MALVACEAE Hibiscus tiliaceus L MYRSINACEAE Aegiceras corniculatum (L.) Blanco VERBENACEAE Clerodendrum inerme Gaertn RHIZQPHORACEAE Bruguiera gymnorrihza (L.) Lamk Rhizophora stylosa Gritf LILIOPSIDA ARACEAE Colocasia esculenta (L.) Schott CYPERACEAE Cyperus stoloniferus Retz PANDANACEAE Pandanus tectorius Sol 91 (4) (5) G MAS Cmn MAS DL MAS G/GB MS DL DL MAS MAS G MAS Bu/GB MS Bu MAS Gn G MS MS C MAS C MAS G MAS (3) Quao Hp Rau mudi Mudi bien, Rau mudi Hp Bim bim Muong bien, Rau mudng bien Hp Thau dau Gia, Cha HpDau Coc ken Dau bien Hp Bong Tra (hoa vang) Ho Dpn nem Su Hp Co roi npffa Ngpc nO bien Hp Dffdc Vet du Dffdc vdi Ldp la mam Hp Ray Mon nffde HpCdi Co gau bien Hp Dffa dai Dffa gai * Chu thich: MS (True Mangrove Species): Thffc vat ngap man chinh thffc; MAS (Mangrove Asssociated Species): Thffc vat gia nhap rffng ngap man; Bu: Cay bui; G: Cay gd; Gn: Cay gd nhd; GB: Cay gd dang bui; DL: Day leo; C: Cay than thao; Cmn: Cd mpng nUdc 3.2 Hien trang tdn che vd mat TVNM 3.2.1 Do tdn che cua TVNM Dp tan ehe eiia thdm TVNM d vffng DNN xa Hffffng Phong dffge quye't dinh ehu ye'u bdi loai Gia (Excoecaria agallocha) va Quao (Dolichandrone spathacea) Trong dd, loai Gia chiem 91,57% dp tan ehe va Quao ehi chiem mdt ty le nhd 8,43% tang tao tan cua tham TVNM (Hinh 2) 3.2.2 Mat cua TVNM CGiS I Quao Hinh Ty le % dd tan che cua TVNM tai cac OTC tren dja ban nghien cffu Ca'u true eua quan xa TVNM la rffng thff sinh kha thuan loai va dffge minh chffng bdi sd' lffgng ca the eiia cae eay gd nhd (Gid, Quao) d tat cd cac ()TC nghien cffu Trung binh tren cd 92 Tap chi Nghien cffu va Phat trie'n, sd (78) 2010 1.685 cay Gia va 142,86 eay Quao, vdi sd' lffgng t h a n thff sinh trung binh ldn Iffgt la 6,23 than/cay vd 3,1 than/cay 3.3 Dac diem phdn bd cua TVNM d vung DNN xd Hilofng Phong Sff phan bd eua TVNM theo hffdng tff pha vao da't lien d vung DNN thudc xa Hffang Phong dffgc phan thdnh vung chinh: i) Vung dat eat ven bd pha gdm cae quan the Muoi bien {Suaeda maritime), Cd gau bien (Cyperus stoloniferus) va Rau mudng bien (Ipomoea pes-capre) tren dat eat am, eay bd lan nhanh ii) Vung dat eao trieu ehi ngap nffde vao mua mffa: chii ye'u gdm quan the Gia (Excoecaria agallocha) va Quao (Dolichandrone spathacea) phan bd Trong dd, Gid la quan the ffu the d vung tao riftig tai sinh thudn loai mgc tren nen dat set eao trieu hoac dat bun ngap trieu trung binh Hi) Vung thffdng xuyen ngap trieu gdm cae quan the eay bui nhff Dffdc vdi (Rhizophora stylosa), Gid (Excoecaria agallocha) va O rd (Acanthus ilicifolius) Ngoai edn ed ede qudn the eay bui phan bo' dffa bd ao, bd de tren nen dat set kho hay am ffdt Sff phan tang eua quan xa TVNM d vung DNN xa Hffang Phong phan tdng chinh: i) Tdng eay gd cd ehieu eao trung binh tff 4-7m gdm ede lodi nhff Dffdc vdi (Rhizophora stylosa), Gia (Excoecaria agallocha) va Quao (Dolichandrone spathacea) tao tan ii) Tang eay bui chieu eao trung binh dffdi 2m gdm ede loai Su (Aegiceras corniculatum), rd (Acanthus ilicifolius) va Ngge nff bien (Clerodendrum inerme) phan bo' dffdi tan cua tang cay go Hi) Tang eay thdo gdm cdc lodi Mud'i bien (Suaeda maritime), Cd gau bien (Cyperus stoloniferus) va Rang bien (Arcostichum aureum) vdi ehieu eao dffdi Im 3.4 Bdn ldp phu thdm TVNM d vung DNN xd HUcfng Phong Dffdi sff hd trg eua cdng nghe vidn tham va GIS ke't hgp vdi ke't qua nghien cffu thffc dia, chung tdi da xay dffng dffge ban dd ve hien trang sd dung dat d khu vffe nghien cffu cung vdi cac ldp phu t h a m TVNM d vung DNN xa Hffang Phong Ke't qud phan tich eho tha'y ldp phii tham TVNM cd tdng dien tich l l , 5 h a (Hinh 3) Trong dd, phan ldn dien tich eay ngap man tap trung d Ru ehinh vdi dien tich 5,24ha ehie'm ty le 45,37% tdng dien tich, sau dd la khu vffe Ru tren vdi dien tich 3,64ha ehie'm ty le 31,52% va sau eung la khu vffe Ru dffdi chi CO 2,68ha ehie'm ty le 23,20% tdng dien tich rv Ket l u a n H/nh Ban hien trang phan bd tham TVNM d xa Hupng Phong, tinh Thffa Thien Hue Ve hien trang thdm TVNM, da xac dinh dffge 16 lodi TVNM thude 16 ehi, 14 ho d Tap chi Nghien cffu va Phat trien, sd (78) 2010 ;^iu^ 93 Hinh Gia (Cha) - Excoecaria agallocha L, cay ; b canh mang hoa; c canh mang qua; sinh canh song l-linh ro gai - Acanthus'ilicifolius L a canh mang hoa; b cum hoa; c hinh thai la: d quan the cay a •*^' hlinh Duoc vol - Rhizophora stylosa Griff Hinh Tham thuc vat ngap man viing DNN Tam Giang - Cau Hai vung DNN thude xa Hffffng Phong, huyen Hffffng Tra, tinh TTH, dd nhdm TVNM chinh thffc cd loai (chiem 37,50% tdng so loai) va nhdm eay gia nhap rffng ngap man 10 loai (chiem 62,50% tdng sd loai), bd sung 10 loai mdi cho danh luc he TVNM d xa Hffffng Phong Da ffng dung edng nghe vien thdm va GIS xay dffng bdn dd ldp phu thdm TVNM de xae dinh dien tich phan bd' cua he sinh thai vdi dien tich ll,55ha Trong dd, Ru ehinh ed 5,24ha, Ru tren 3,64ha va Ru dffdi 2,68ha Day dffge xem la nhffng thong tin ed y nghia thffc tien qudn ly va dinh hffdng phdt trien ben vffng tai nguyen vung dat ngap nffdc Hai loai'Gid (Excoecaria agallocha) va Quao (Dolichandrone spatliacea) quyet dinh mat dp eay, trung binh ed 10.500 than Gid/ha va 422 than Quao/ha Tffang ffng dd tan che ciia Gia chiem 91,57% va Quao ehi chiem mpt ty le nhd (8,43%).' • Ve phan bo, tham TVNM vung DNN xa Hffffng Phong cd sff phan bo theo chieu thdng dffng theo tang chinh: tang eay gd nhd, tang eay bui va tang cay thao Sff phan bd theo khdng gian dffpc phan lam vffng chinh: 94 Tap chi Nghien cffu va Phat trien, sd (78) 2010 eay vung da't cdt ven bd phd; cay vung dat cao trieu ehi ngap nffdc vao mua mffa va cay vung thffdng xuyen ngap trieu Kien nghi Vung duyen hai mien Trung ndi chung va dam pha ven bien TTH ndi rieng dffgc xac dinh la mdt nhffng dia phffang se chiu anh hffdng nang ne nhffng tae ddng eua bie'n ddi hau Vi vay, tren ca sd ket qua nghien cffu ve hien trang TVNM cho thay dinh hffdng quy hoach phat trie'n md rgng dien tich TVNM eiia ehinh quyen dia phffang la hoan toan kha thi, nham phdt huy vai trd cua TVNM dd'i vdi vung ven bien cijng nhff tang kha nang dd'i phd va thich ffng vdi nhffng tae ddng cua bie'n ddi hau dang mdt ro ret nhff hien HCT-MVP-TTP TAI LIEU THAM KHAO FAQ and Wetlands International (2007), Mangrove Guidebook for Southeast Asia Printed by Dharmasarn Co., Ltd Pham Hoang Hp (2001), Cay co Viet Nam, tap I, II, III, Nxb Tre, TP Hd Chi Minh Phan Nguyen Hdng (chu bien) (1999), Rdng ngap man Viet Nam, Nxb Nong nghiep, Ha Npi Ton That Phap (chu bien), Lffdng Quang Ddc, Mai Van Phd, Le Thi T r i , Phan Thj Thuy Hdng, Nguyen Van Hoang, Vd Van Dung, Hoang Cdng Tin, Trffdng Thi Hieu Thao (2009), Da dang sinh hoc dphi Tam Giang-Cau Hai, tinh Thda Thien Hue, Nxb Dai hpc Hue Sd Khoa hpc va Cdng nghe Thffa Thien Hue, Dac diem hau-thuy van tinh Thda Thien Hue, Nxb Thuan Hda, Hue, 2004 McLeod, Elizabeth and Salm, Rodney V (2006), Managing Mangroves for Resilience to Climate Change lUCN, Gland, Switzerland 64pp Oilman, E.L., et al (2008), Threats to mangroves from climate change and adaptation options, Aquat Bot., doi:10.1016/j.aquabot.2007.12.009 Tomlinson (1986), The Botany of Mangroves Printed in United of American TOM TAT Hien trang tham thffc vat ngap man d vung dat ngap nffdc Tam Giang-Cau Hai, tfnh Thffa Thien Hue dffpc xac djnh gdm 16 loai thffc vat ngap man thupc 16 chi, 14 hp Trong dd, hai loai Gia (Excoecaria agallocha) va Quao (Dolichandrone spathacea) quyet dinh mat dd d^day, vdi gia trj trung binh 10.500 than Gia/ha va 422 than Quao/ha Tffpng ffng dd tan che cua Gia chiem 91^57% va Quao ehie'm mdt ty le nhd (8,43%) Ben canh dd, nhd sff hd trd eua edng nghe vien tham va GIS xay dffng ban dd Idp phu tham TVNM da xac dinh dffpc dien tich phan bd la 11,55ha Cac ke't qua nghien cffu cau true, hien trang phan bd va lap ban dd tham TVNM cd mdt y nghTa quan trpng viec quan ly, phan vung quy hoaeh eung nhff hoaeh djnh bao tdn va phat trien ben vffng he sinh thai ABSTRACT THE CURRENT SITUATION OF MANGROVES AT TAM GIANG-CAU HAI COASTAL LAGOON, T H Q A THIEN HUE PROVINCE _^ The results of study on mangroves at Tam Giang-Cau Hai coastal lagoon, Thffa Thien Hue province consists of 16 mangroves species belong to 16 genuses, 14 familiar are presented Excoecaria agallocha and Dolichandrone spathacea are most densities, 10,500 trunks per hectare and 422 trunks per hectare in average value Correlative with Excoecaria agallocha cover value 91.57% and Dolichandrone spathacea value 8.43% In other hands, under supporting of remote sensing and GIS techniques on mapping mangroves cover which showed the area of mangroves cover with value 11.55 hectare Mangroves structure, distribution characteristics and cover map has been played a vital information/data tor management, zoning, and conservation planning and sustainable development the ecosystem ... ABSTRACT THE CURRENT SITUATION OF MANGROVES AT TAM GIANG- CAU HAI COASTAL LAGOON, T H Q A THIEN HUE PROVINCE _^ The results of study on mangroves at Tam Giang- Cau Hai coastal lagoon, Thffa Thien Hue... Printed in United of American TOM TAT Hien trang tham thffc vat ngap man d vung dat ngap nffdc Tam Giang- Cau Hai, tfnh Thffa Thien Hue dffpc xac djnh gdm 16 loai thffc vat ngap man thupc 16 chi, 14... Hoang, Vd Van Dung, Hoang Cdng Tin, Trffdng Thi Hieu Thao (2009), Da dang sinh hoc dphi Tam Giang- Cau Hai, tinh Thda Thien Hue, Nxb Dai hpc Hue Sd Khoa hpc va Cdng nghe Thffa Thien Hue, Dac diem