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Tgp chi Khoa hgc Tnrdng Dai hgc Cdn Tha Phdn A Khoa hgc Tu nhien Cong nghi vd Moi trudng 30 (2014) 105 114 ̂ Tap chl Khoa hoc Tru''''dng £)ai hgc Can Thd •^f website sj ctu edu vn DANH GIA LirgfNG CACBON[.]
Tgp chi Khoa hgc Tnrdng Dai hgc Cdn Tha -^ •^f Phdn A: Khoa hgc Tu nhien Cong nghi vd Moi trudng: 30 (2 Tap chl Khoa hoc Tru'dng £)ai hgc Can Thd website: sj ctu edu DANH GIA LirgfNG CACBON TICH LUY CUA SINH KHOI R I T N G TRAM TREN NEN ©AT THAN BUN TAI VlTOfN QUOC GIA U MINH THU*g(NG Truong Hoang Dan', Quach Trudng Xuan' va Bui Tnidng Tho^ ' Khoa Moi trudng vd Tdi nguyen Thien nhien, Tnrdng Dgi hgc Cdn Tha ^ Khoa Khoa hge vd Ky thudt Dgi hoc Aarhus, Dan Mgch ABSTRACT Thdng tin chung: Ngdy nhan: 27/] 1/2013 The study "the assessment of carbon accumulation of Malaleuca forest on peat so Ngdy chdp nhgn- 25'02/20I4 at U Minh Thuong National Park" was carried out in order to estimale carbon accumulation of two age le\'els (under len and over ten years) afforests The Title: analyzedparameters including diameter of breast height (DBHi.3m): height, de biomass, litterfall of Melaleuca and shrubs were collected in 40 standard quadra The assessment of carbon (10m X 10m) Results showed that under 10-year-olds forest had higher density accumulation of (5,940 individual per ha) than that of over 10-year-olds (4,440) In contrast, th Malaleuca forest on peat DBHiim and height of 10-year-olds forest were lower than that of the other age, soil at UMinh Thuong with 4.99 cm and 5.21 m compared with 6.16 cm and 6.24m, respectively Ther National Park was insignificantly different litterfall between the two age of forests ranging from 1.57 lo 1.61 ton per Similar to litterfall, carbon accumulation of two age o Tir khda: Melaleuca forests was insignificant discrepancy with figuresfluctuatedbetween Tich liiy cacbon, rieng 26.05 and 26.92 ton C per Nine plant species in under 10-year-olds forest an trdm, ddt than bim, Vudn ten species in over 10-year-olds forest were found, with (Phragmites vallatoria ( quoc gia UMinh Thugng Veldk) and (Stenochlaena palustris (Burm) Bedd) were common species Keywords: Carbon accumulation, Melaleuca forest, peat soil, UMinh Thuong National Park TOM TAT Di tdi "Bdnh gid hdm luang cacbon tich lOy cua sinh khoi rimg tram tren nin dd than biin tgi Vudn quoc gm UMinh Thugng" dugc thuc hiin nhdm u&c linh lugn cacbon tich ISy cua rimg tram d hai tudi nhd han mudi vd ldn han mudi Cdc Ihong so khdo sdt bao gom dudng kinh thdn d cao 1,3 m, chiiu cao thdn, mg do, sinh khdi, Ihdnh phdn vdt rung cua trdm vd tdng cdy bui dugc thu thdp d 40 d lieu chudn (10m x lOm) Kit qud nghien ciru cho thdy rimg irdm dudi 10 tudi c mdl dp 5940 (cdy/ha) cao han mat dg rimg trdm ldn han mudi tudi (4440 edy/ha) Nguac lgi, dtrdng kinh ngang nguc yd chiiu caa ciia rimg trdm dudi 10 tudi thdp hon dudng kinh ngang nguc vd chieu cao cua nmg trdm co dg ludi ldn han mudi vdi gid tri tuang img ldn lugi Id 4,99 em vd 5,21 m so vdt 6.16 emvd 6,24 m Khong cd sir khdc biel vi thdnh phdn vgt rung d rimg trdm co dg tudi nhd han mudi vd ldn han micdi, vdi gid tri dao dgng tir 1.57 (tdn/ha) din 1,61 (Idn/ha) Tuang lu thdnh phdn vgt rung, hdm lugng cacbon irdc tinh ciia rimg trdm theo h luoi nhd han mudi vd ldn han mudi khong khdc cd gid trj ldn lirgt dgt 26,92 (tdn C/ha) vd 26,05 (tdn C/ha) Chin lodi thuc vdt d rimg trdm nho han mu tuoi vd mudi lodi thuc vgt d rimg trdm ldn han mudi tudi dugc tim thdy say (Phragmites vallatoria (L)Veldk)vd chogi ((Stenochlaena palustris (Burm) Bedd) Id nhirng lodi chU yiu Tap chi Khoa hgc Tnr&ng Dai hgc Can Tha Phdn A: Khoa hoc Ttr nhiin Cdng nghi vd Moi inr&ng- 30 (2014): 105-} 14 GIOITHIgU Vdi tim quan ttpng cua eae bl chda cacbon d rung nhiet ddi, ttong gin ra^t thap niin qua nhilu t l ehdc fren the gidi da cd cie nghiin ciiu lien quan din sinh khii rung v i lupng cacbon tich ldy ttong cic hf sinh thai rdng 3.h dua phuong phip lulin hoac cic de xuit vl thi chl chinh sich ttong vifc bao vf cic khu rung nhift ddi, su dung dit rdng ben vung vi gia tti mdi frudng frong tinh hinh biln dii hgu toan eiu (Bio Huy, 2009) Tai Viet Nam, viec nghien cuu dl giim phat thii CO2 biu quyen ciia riing mdi frong giai dogn khdi dau vi cdn kha mdi la Trin Dinh Di vi Ll Quic Doanh (2009) sd dung phuong phap danh gii nhanh tieh ldy cacbon, dii tugng la cic phuang thdc nong lim kit hgp tgi vung dim vudn qude gia Tam Dio Kha nang tich liiy cacbon dugc ^ i nhan tai cac phuang thde rdng Vii + Bach Dan; Vii + Keo tai tugng vi Vai + Thong lin lupt dgt 16,07 tin/ha; 21,84 tin/ha va 20,81 tin/ha Do Hoang Chung va cpng tic viln (2010) da dinh gii nhanh Iugng cacbon tieh luy ttIn mit dit eiia mot sl ttgng thai thim thue vit tai Thii Nguyin, kit qua eho thiy: frgng thai tham ed, tting ciy byi xem gd tai sinh lugng cacbon tieh luy dat 1,78 - 13,67 tin C/ha; nmg ttlng dat 13,52 - 53,25 tin C/ha; ning phye hli ty nhiin dat 19,08 - 35,27 tin C/ha Tai Ddng bing song Cdu Long, rung fram la mpt kieu riing die thu eua khu vuc nhung nghiin cdu vl kha ning tieh luy cacbon tren mat dat cua rung ttam hau nhu edn mdi la va ehua dugc quan tim dung muc Tu thuc tien ttIn dl tii ''dinh gii lugng cacbon tich luy ciia sinli khoi rimg ttam ttIn nen dat than biin tai Vudn quoc gia U Minh Thupng" dupe thye hien de gdp phan eung cip cic co sd dfl lieu, thong tin vl ddng gdp ciia he ^inh thii riing ttim giim giy hifu dng nha kinh, tu cd co sd khuyin cao nhan rpng va dinh hudng cho vifc ehi tta dieh vy moi trudng PHU"0(NG PHAP NGHIEN CUtJ 2.1 Dja diem nghien ctru va tbdi gian •ghien cdu Nghien cdu duge tiln hanh tai cic tieu khu riing tram co dp tudi nho hem 10 (tilu khu 47, 57, 60) vi cac tilu khu co tuli ldn hon 10 (tiiu khu 46A, 46B, 48, 50, 58) trin nin dit than bun tai Vudn quic gia U Minh Thuang td thang 10 nim 2012 den thing nam 2013 2.2 Phinrng phap nghiin cdu 2.2.1 Phuang phdp thu thdp so lieu ngodi thuc dia Mdi tieu khu tien hinh l^ip 05 d tieu chuin cd diln tieh 100 m- (10m x 10m) duge bl tri ngiu nhiin Tong sd tieu ehuin phai lap theo hai cip dp tudi ciia rdng fram tten nin dit than bun li 40 d tilu chuin 100 m^ Tai moi d tilu ehuin tien hinh thu thgp cic chi tilu: (1) Dudng kinh thin cay d dp cao 1,3 m (DBHi,3), dp eao thin cay vut ngpn (H) vi mat dp cay ttong d tieu ehuin (2) Tgi rdng ttam vdi dp tuoi nho hon 10 chpn 15 ciy dgi diln vi riing ttam vdi dg tuli Idn ban 10 ehpn 25 cay dai difn Tiln hanh chat sit ^Ic vdi vj tti chgt each mat dit 10 cm Sau tien hinh phin chia vi can sinh khdi theo tung bO phin rieng biet: thin (SKT), ciiih (SKTc), li (SKTi) (3) Thu thap sl lieu sinh khoi ting cay byi: dim vi phin logi cay byi theo tung loai, sau dd thu toin bp so loii cay byi cd mat ttong d tieu chuan m^, cin frgng lugng cay bui theo tdng logi (ky hieu sinh khoi tuoi theo tiing loai) Sau cin xong khii Iugng sinh khdi tuoi timg logi cay bui tiln hinh thu miu moi logi de dem vl phong thi nghiem phan tieh (4) Trong moi tieu ehuin di chon, xie djnh sinh khii eua ciy frim tiln hinh bd fri 01 tiii thu vit ryng vdi diln tich m^, dugc bd tti gifla va tteo dudi tin ciy, tdng so tui thu vat rung Ii 40 tiii m^ Moi tui miu dugc thu 02 lan/thang ttong vong 09 thing Vit ryng dugc thu ttong tui sl dugc phan thiidi canh, la, bong vun 2.2.2 Phuang phdp ndi nghiip Tgi riing fram cd dp tuli ttam nhd hem 10 so ciy dgi diln li 15 ciy, tuang ty riing tram cd tuoi ldn hon 10 so cay dai difn Ii 25 ciy Tien hanh xay dyng eong thde tinh sinh khoi tuoi ciy fram d hai dp tudi dua vao dudng kinh than ciy ngang nguc va sinh khoi tuoi thuc tl cua sd ciy dgi dien theo ham luy thda y = ax*" Tien hanh cit nho mau ein phin tich sau siy kho d 105''C, dinh ky can sinh khoi khd eua eiia ciy frim theo tung thinh phan nhu: thin (SKKt), cinh (SKKc), li (SKKi); ting ciy byi phin theo tdng loai; tang vat rung phin theo canh li bdng Kit qui lin eudi eimg dugc ghi nhan sau kiu sinh khdi khd cd gii fri khon^ thay ddi Tiiy theo thinh phan eu the, thdi gian siy kho bien dpng tir 24 - 48 gid Kl din tinh hf so ty If gifla sinh khdi kho (K (kg)) vdi sinh khii tirai (T(kg)) thejo cong thdc k = K/T Cuoi eung tirdi sinh khdi khd cho Tap chi Khoa hgc Tnrdng Dgi hgc Can Tha Phdn 4: Khoa hgc Tif nhien, Cdng ngh? vd Mdi tru&ng 30 (2014): I0s-]I4 timg bp phin ciia ciy va lam phin bing cich nhan sinh khii tuoi (T) ciia eae bg phin tuong ung vdi he so k nghia li K = T*k 2.3 Phinmg phip sir ly so lieu Ting hgp toin bp sl lieu vi sinh khoi tuoi v i smh khii kho cua timg logi ciy frim, cay bui, vit rung tilu chuin dai dien thinh bieu bing phin mim Microsoft Offiee Excel 2010 tuong ung theo timg dp tuoi eua sinh khoi rung trim tten nin dat than biin dl tinh smh khdi tuoi va sinh khoi khd cac phin tten toin bg sinh khoi rimg trim ttIn dat than biin Dimg phin mim SPSS Statistics 13.0 (USA) dl phin tich su khae bift giua eae thinh phan sinh khoi Cach dinh gii lugng cacbon tich luy eua sinh khdi rirng ttim fren nin dit than biin theo dp tuoi bing phuong frinh toan Cacbon-RaCSA cua ICRAF Theo Meine Van Noordwijk (2007) lugng cacbon tich luy phin fren mat dat ttong cac ttang thii ldp phu thye vat bao gdm: cacbon tich IGy ttong thim thyc vit (ciy gl, ciy byi, tham tuoi) vi vat rung Lugng cacbon ti'ch luy duge tinh dua tten ting sinh khii kho frIn mat dit theo eong thuc: W^bon = 0.46 *DW^v (tin C/ha) Wcacbon lugng cacbou tich liiy ttong sinh khii (tin/ha) DWabove = lugng sinh khoi khd ttIn mat dat (tin/ha) DWabove = W»MKi + Wsbnib + Wbuer (tin/ha) Wwood lupng sinh khii khd ciia ting ciy gl (tin/ha) Wshmb lugng sinh khii kho eua ting cay bui (tin/ha) WLner lugug siuh khii kho eua ting vit rung (tin/ha) KET QUA THAO LU^LN 3.1 Dac diem cac thong so lam hpc cua riJmg tram tren dat than biin 3.1.1 Mat do, DBHi.3 vd H ciia rimg trdm tren ddt than biin d cimg dg tuoi So sinh cie ehi tieu vl lim hpe nhu mit dp, DBHi.3, H cua rung ttim cimg mpt cip dp tudi cd sy khic biet nhu Bing Bang 1: Mgt dp, DBHijva H ciia rimg tram Cling d$ tudi Mat (cay/m^) Him) TK DBH.j (cm) Loai rimg 0,528*0,092"" 4,1(U0,12' 4,50i0,07" 47 Rimg 10 tuoi 50 6,86±0,29' 6,68±0,17' 0,416*0,087" 58 5,90±0,11" 7,21*0,11' 0,620*0,090' Ghi chu: Trung binh ± Dg lich chudn Cdc cfnr cdi theo sau timg col Hide thi se khdc biit cdynghta Ihdng ki 0dem dinh Lhrncan P 0,05) Doi vdi rimg Idn hem 10 tuoi dudng kinh ngemg ngyc eua than ciy dao dpng td 5,79 ± 0,24 din 6.86 ± 0,29 (cm) Tucmg tu nhu rimg tram nhd hon 10 moi ciy trim d dp mdi Idn hon 10 ciia cac tilu khu CO gii tri DBHi,3 khdng dong diu Trong tilu khu 50 khic biet vdi cic tilu khu cdn lgi frong eiing dd tuli (p < 0,05) Chieu eao than cay viit ngpn dao dpng tii 5,25 ± 0.08 din 7,21 ± 0,11 (m) Trong tilu idiu 46B va tieu khu 48 khong khic bift (p > 0,05), cic tilu khu edn lai khae bilt (p < 0,05) Mat dp ciy dao d^ng tix 0.178 ± 0,033 din 0,620 ± 0,090 (eiy/m-) Trong d6 tiiu khu 46B khic biet vdi eae tilu khu cdn lai ngoai trd tieu khu 50, cic tilu khu Igi khong khae bilt (p> 0,05) 3.1.2 Mat do, DBHjj vd H cua rimg trdm trin ddt than bun theo hai cdp tudi Be khao cic dac diem lam hoc giiia hai cip dp moi ciia rimg cd sy khic bift hay khong, nghien Tap chi Khoa hpc Tntang Dgi hgc Cdn Tha Phdn A: Khoa hoc Tu nhiin Cong nghf vd Mdt tnrang: 30 (2014): 105-114 CUU tiln hinh thing ke cic thong sl DBH13, H va mat dp de tim gia tri trung binh Vdi rimg tram ed dp tudi nhd hon 10 thdng kl cae thong so DBHu, H (vdi n = 891) va mat dd (vdi n = 15); rimg tram cd dp mli ldn ban 10 thing ke cae thong so DBH1.3, H (vdi n = 1109) v i mat dp (vdi n = 25) Kit qua thing kl cac thdng so DBH1.3, H vi ra|t dp ciia rimg theo hai eip dd tuli duge thi hien qua Hinh 1,2 v i Dudng kinh thin ciy ngang nguc va ehieu eao riing cd dp tuli nho ban 10 sl nho han so vdi rimg cd dp tuoi ldn hon 10 Nguge lai, mgt dp eua rimg cd dp tuoi nho han 10 se cao hon so vdi rdng eo dp tuoi Idn hon 10 Dieu niy ed nghTa ttong qua ttinh sinh trudng vi phat ttiln cic ciy cd su eanh ttanh vl khdng gian va dinh duong, nhung cay khong dii nang eanh tranh se chit di nin mat dp ciy se giam xudng ^ _ E ^ X a P < 0,05 P < 0,05 0.6 ^ 0.5 ^-^ ^ 0.3 cS 0.2 10 Do tuoi Hinb 3: Mat dp ciia rinig theo hai tnoi 3.2 Thanh phan tang vat rung tai khu vuc nghien ciru 3.2 Thdnh phdn tdng vdt rung cua rimg trdm tren ddt than bim d cimg dg tuoi Theo Dgng Quie Cudng (2009) vat rung li cac thinh phin chinh ciia ciy nhu: canh, la, bong bi dio thai theo thdi gian qui ttinh lio hda d cic te bio song tgi nhung bO phgn cua cay hoge eie tic dpng bdi nhung ylu to bin ngoii lim cac phan hi thay doi Vat ryng thu dupe eo sy thay doi tiiy theo miia, dp tuoi cua ciy Kit qui so sanh ciia tang vat rung dupe the hien qua Hinh vi 10 Do tuoi Hinh 1: DBHijciia riing theo hai d$ tuoi 7.0 0.7 P < 0,05 6.0 Tong sinh khoi tucri cua ting vat ryng bao gdm eanh, li, bong: la frim li thinh phin chii ylu eiia ting vit rung Trong eanh vi bdng chilm ti 11 xap xi Khoi Iugng ting v^t rung cua rimg ttam nhd hon 10:canh 0,196 kg/m-, li 1,89 kg/m^ bdng 0,190 kg/m-tudi va rimg fram ldn hem 10 tudi CO cic thinh phin: cinh 0,195 kg/m-, li 1,87 kg/m-, bong 0,182 kg/m- .ff^4«/::5^ 5.0 > - : : i, >(- — X 4.0 'i> I _ — 2, 11 _ = 2.0 • Canh H La 1.0 0.0 10 Dg tuoi Hinb 2: H ciia rung theo hai d$ tuoi • Bong : _ "I': i ~ _ '"I"" : ^.- - i j 13 : J ^^ Rirng < 10 tu6i Hinh 4: Sinh khoi tinri cua tang vat rung tai rimg tram co dp tudi nhd bon 10 Phdn A Khoa hpc Tlf nhien Cong nghp va Moi tnrang:30 (201-1): 105-114 Tap chi Khoa hoc Trvang Dai hoc Can The ^ - f \ % 8i7Wy?K -.i , "~\ : .-J I -/ III nCanh>1 : : " " : ^ v QBong '/ - X^ : v : ^^ Rimg > 10 tuoi Hinh 5: Sinh kboi tuoi cua tang v^t rung tai rung tram co tudi Idn ban 10 3.2.2 Thdnh phdn tdng vdt ryng ciia rimg trdm tren ddt than biin theo hai cdp dg tuoi Thinh phin vit ryng ciia rimg fram thi li chilm ti le chii yeu vdi ti If >80%, hai tiianh phan eon Igi cua ting vit rung chilm ti II gin bing va khong eo su khic biet giira hai thinh phan niy Lugng sinh khoi khd ciia ting vit rung theo hai cip dp mli khong khic bilt {p > 0,05) Dilu niy cd nghTa vdi rimg trim nho ban 10 tudi mat dp cay cao, dudng kinh thin ciy nhd thi lupn^ vat ryng khong khic biet vdi rimg ttim cd dp tudi ldn mat dp ciy it nhung dudng kinh than cay ldn Sinh khii tuoi cua ting vgt rung theo hai miia mua, ning vl mat gii tri cd chlnh If ch nhung khong khie bilt rimg fram cd dp tuli nho han 10 tnmg binh sinh khdi tuai ting vit rung ciia cic thing miia mua va miia ning cd gii trj tucmg inig: 1,29 ± 0,05 (kg/m^); 1,25 ± 0,03 (kg/m^) Ci rimjg ttam CO dp tuoi ldn ban 10 tnmg binh sinh khdi tuoi ting vit ryng nhu mua mua 1,28 ± 0,35 (kg/m^); miia ning 1,23 ± 0,26 (kg/m-) Gifla hai miia ttong nim ting vat rung khong khic bift (p > 0,05) Theo Dang Qude Cudng (2009) khio sit ning suit vat ryng va su phin huy li Tram {Melaleuca cajuputi) tgi vudn Quoc gia Trim Chim thi v^t ryng d mua mua eao ban miia ning Vit ryng rimg ttam tten nen dit than bun d U Minh Thupng khong khae bilt theo mua co thi su chenh lech tudi ciy rimg khong ldn, nin dit than bun d U Minh Thugng khic nen dat phen d Tram Chim 25 M 20 •^ 15 =• 10 [ ^ 10 12 nRimg10 tudi I -^, Thang Hinli 6; Sinli Idioi Ichd ciia canb ruDg tlieo liai cip dd tudi 160 „ 140 ^ -rt - * i rir irS-f* i -t rtrS 120 i]i 100 ;j ;1 ;•' ? 80 ;l; - 60 I J 40 20 1; U Rung< 10 tudi Thing \\ 1 \\i ;j i|i ; :|; ;\\\ \>\ \>\ [yij Rimg > 10 tuli Hinh 7: Sinh khoi kbd cua la rung tbeo bai cip d$ tuli Tgp chi Khoa hgc Tnr&ng Dgi hgc Cdn Tha Phdn A: Khoa hgc Tu nhien Cdng nghi vd Mdi Inc&ng: 30 (2014) 105-114 i *j|y] 10 11 URung10tu6i Hinh 8: Sinh khoi kho cua bong rung tbeo bai cap dd tuoi 3.3 Thinh phan ting cay bui tai kbu vuc nghiin ciiii rimg ttim theo hai dp mdi ket qui cho thay sd loai xuat hifn tai tieu khu la 11 loai dugc thi hifn d Bang Qui trinh khio sit thuc dia tgi tilu khu cua Bing 2: So loii vi trpng lugng tdng loai ciia tang cay byi tai khu vi^c nghiin cihi STT 01 02 03 04 05 06 07 08 09 10 11 Loii ciy Chogi (Stenochlaena palustris (Burm) Bedd.^ Diy vie (Cayratia trifolia (L.) Domin.^ Bong bong (Lygodium scandens (L.) Sw.^ Sgy (Phragmites vallatoria (L.) Veldk.^ Mua (Melastoma dodecandrum Lour) Rang (Asplenium nidus) Cuang (Scleria sumatrensis Retz) Dau ma (Cassia tora L) Day mo (Paederiafoetida L) Miy (Flagellaria indica L) Ddn (Diplazium esculentum (Retz) S\y) Tdng Rimg ttim co tuoi nhd han 10, say li loii ed mat dp cao nhit vdi 10,4 (eiy/m-) tiep din li Chogi vdi mat dp 3,40 (eiy/m-) diy la hai loii die tnmg cua rimg trim tten nen dit than bim, Dau ma loii ed mat dd thip nhit vdi 0,13 (eay/m-) Rimg fram cd df tuli ldn ban 10: Say vin li loii ehu yeu vdi m|t dp 5,52 (eiy/m-), Chogi vol mat dp 2.52 (eiy/m^), Ddn la loii eo mat thip nhit vdi 0,08 (ciy/m^) Nhin chung, mat dd cic loii rimg ttim cd dp tudi nho hon 10 cao han so vdi rung frim cd dp tuli ldn han 10 cd thi rimg frim nho han 10 tuli cay chua khep tin nen inh sang mat ttdi cd thi chilu xulng ting cay byi, giup tang cay byi sinh trudng vi phit trien tot Ting cay bui ciia rimg ttam theo hai cap dp tuoi khic bilt vl frpng lugng khd (p < 0,05) Rung M^t d9 (c3y/m^) ) (llS/m= 10 2,20 0,31 0,01 0,90 0,49 0,26 0,01 0,05 0,29 0,02 4,53 ttam cd dp tudi nho, ttpng lugng kho tnmg bmh cua ting cay bui se eao vi nguge lai Dieu cd nghTa ciy trim d dp tuoi nhd chiu su cgnh ttanh gay git vl khdng gian sdng, dinh dudng vdi cae loii cay byi Khi riing ttam den tudi tnrdng thinh tde eo dp khep tan rpng thi sue canh ttanh vl khong gian cua trim mgnh ban cae loii ciy bui, din din sl loai cay byi dudi tan fram se suy ^am vl mat dp keo theo suy giim vl trpng lugng 10 2,52 0,68 0,12 5,52 0,84 0,76 0,04 0,24 0,60 0.08 3.4 Sinb khdi turn va sinh khoi kho ciia rijng tram tren dit than biin 3.4.1 Tuang quan dirdng kinh ngang nguc vd sinh khii tirai cdy trdm theo tuoi Theo Le Minh Lpe (2004) sinh khdi ciy trim phu thupc vio dudng kinh cua cay dd doi vdi nhung tilu khu cd dudng kinh cay cang cao thi Tgp chi Khoa hoc Tnr&ng Dgi hgc Cdn Tha Phdn A Khoa hgc Ttr nhien, Cong nghi va Moi tnr&ng- 30(2014) 105-114 chat chl theo ham sl luy thira SKT = 0,438 x DBH'-^^ vdi R2 = 0,892 sinh khdi tuoi cua ciy trim cang ldn Day la each xay dung phuang trinh xac dinh sinh khdi tucri dya vao dudng kinh thin ciy ngang nguc vi sinh khoi tucri cua cay ngoii thue dja tai eie d tieu chuin Tuong tu vdi rimg trara cd mdi nhd hem 10, kit qui phin tfch tuong quan cho thiy dudng kinh thin cay ngai^ nguc vi tdng sinh khoi tuoi tai lam phin cd dp mdi nhd hon 10 cd mli tuong quan chat chl theo him s6luy thda SKT = 0,658 xDBH'™' vdi R== 0,922 Kit qui phin tich tuong quan cho thiy dudng kinh thin cay ngang ngyc vi tdng sinh khdi tuai tai lam phin cd dp tuoi nho hon 10 cd moi tuang quan 30 - n 4187v'-^"' R^ = 0,8924 ^20 » 10 t^*^ DHB,,4 Hinh 9: Tuong quau giiia DBHijva TSKT rirng tram co dp tuoi nhd hon 10 150 -:—— H i^ 50 - ^ oJ ) _ — ^ _^_ „ _ — j v = 0.658x'-' R= = a932- • ^(^i*'*'^ 10 15 20 25 DHB,j Hinh 10: Tirong quan giira DBHi^va TSKT rimg tram cd dd tudi Idn bon 10 Bing 3: Sinb kboi tuoi va DBHijcua 15 cay dgi dien tai rung tram cd dd tuli nhd bon 10 TT c9y mSu DBH,,3 (cm) SKT,{lig) SKT, (kg) SKT, (kg) TSKT (kg) 01 4,40 3,75 2.13 •1,67 7,55 03 4,10 4,06 2.03 1,62 7,71 03 5,10 5,03 2.48 1,84 9,35 04 4,50 4,92 2,44 2,01 9.37 05 7,90 19,68 4.79 2,41 26,88 06 5.10 6,68 1,85 1,26 9,79 07 4.10 6,21 1.83 1,17 9,21 08 4,70 7,25 1,48 1,43 10,16 09 4,30 3,82 2,06 1,58 7.46 10 4.80 6,82 1,94 1,45 10,21 11 5,40 9,34 1,82 1,28 12,44 5,20 8,42 1.87 1,28 11,57 5,10 7,48 1,31 1,26 10,05 6,10 14,84 2.94 1,67 19,45 15 5,90 12,94 2.66 1,48 17,08 Tap chi Khoa hgc Tnr&ng Dgi hgc Cdn Tha Phan A- Khoa hgc Tu nhien Cdng nghi vd Moi irir&ng: 30 (2014): 105-114 Bang 4: Sinb kbdi tuoi, DBHM cua 25 cay dai diln tgi lam phin cd d$ tuli ldn hon 10 DBHo (cm) SKT, (kg) SKT (kg) SKT, (kg) TT cay mau TSKT (kg) 5,30 7,80 1,40 01 1,05 10,25 02 4,90 7,40 1,20 0,80 9,40 03 5,10 8,20 1,25 0,9 10,35 04 5,10 7,90 1,20 0,8 9,90 05 15,2 43,84 8,73 246 55,03 06 7,30 20,8 9,31 3,65 33,76 07 4,60 3,34 1,92 0,91 6,17 08 5,30 6,90 2,04 1,27 10,21 09 5,30 7,71 1,76 1,08 10,55 10 5,80 8,95 2,46 1,38 1279 11 5,10 7,41 1,22 1,19 9,82 12 4,80 6,81 1,22 1,26 9,29 13 9,60 31,06 1,06 2,08 34,2 14 10,4 37,81 5,87 2,12 45,8 15 5,10 7,64 1,44 1,29 10,37 16 19,2 54,89 12,73 3,87 71,49 17 8,10 22,4 3,80 2,73 28,93 18 4,70 7,10 1,25 0,90 9,25 19 4,90 7,40 1,20 0,80 9,40 20 5,10 8,10 1,30 1,05 10,45 21 5,30 8,40 2,10 1,30 11,80 22 6,40 2,30 1,60 15,70 11,8 23 4,60 7,15 1,40 1,25 9,80 24 6,10 10,4 1,85 1,60 13,85 25 5,30 7,90 2,05 1,45 11,40 3.4.2 Sinhkhoi tuoi vd sinh khoi kho eua rimg ttanli giy git vl khong gian sdng ciia cic loii ttong trdm trin ddt than biin rimg ttim Rimg eo dp tuoi Idn ciy da khep tin nen sue canh tranh ve khdng gian mgnh, cic loii ciy Kit qui nghien cdu cho thiy sinh khoi kho ciia byi dudi tin se din dan giim di khong dii sue cay ttim, ting vit rung vi tham cay bui ducri tan eanh ttanh vdi ciy ttam Nguge lgi, rimg cd dp mdi ttim tgi cae tilu khu d logi rimg ttim trin nin dit nho hon 10 li giai doan canh ttanh gay git giua cie than biin dng vdi cip tuoi nho hon 10 tuoi va ldn loii ciy bui vi ciy ttam nen giai dogn m$t dp hon 10 tuli thi sinh khoi khd ciia eac logi thinh vi sinh klili mai va sinh khdi kho ciia ciy bui ldn phin tuong dng deu cd sy khae bilt (do hon Rieng tang vgt rung cilahai cip dp moi khdng p 0,05) Vdi dit cua tilu khu dgt 26,05 (tin C/ha) 35 P> 30 25 20 -r^T^-rJJH;^ 10 e=r^s~=s =E^"-:-^:^"~~ Hr:^H?:;=s; 10tu6i Loai rimg Hinh 11: Ham lirong cacbon tich luy tren mat ak cua rimg trim theo hai c^p 89 tu6i Trung binh ham luong cacbon cua rimg tram co tu6i nho hon 10 Ion hon so voi trung binh ham luong cacbon co tuoi Ion hon 10 rimg tram co tudi rimg Ion hem 10 chira tiju khu 46B, day la tieu khu co mat cay rlt thua din din hani luong cacbon tich luy nho hon rit nhiiu so voi cac tieu khu lai cung cip dp tu5i Ngogi trir Tgp chi Khoa hgc Tnrdng Dgi hgc can Tha Phan A: Khoa hoc Tu nhien Cong ngh^ va Moi tnr&ng 30(2014) 105-114 tilu khu 46B, cac tilu khu lgi gii tri cacbon tieh luy cua rdng tram Idn hon 10 hioi dao dpng tii 25.64 din 35,07 (tin C/ha) Idn hon so vdi lugng cacbon tieh luy cda riing trim nho hon 10 tuli (25,07-28,82 tin C/ha) Vifc xie dinh him Iugng cacbon tieh luy tten mgt dit eua sinh khii rung ttam frIn nin dit than bim tgi Vudn qude gia U Minh Thugng la mpt de tai nghien cuu hoan toin mdi So vol nghien cdu cda Vu Tin Phuang (2006) vi trii lugng cacbon tich liiy ciia ciy bui dudi m li 9,89 tin C/ha vi kha nang tich luy cacbon cda rimg Trang {Kandelia obovata Sheue) ttong ven biln huyin Giao Thdy, tinh Nam Dinh d cap tuli li 40,01 tan C/ha (Mai sy Tuin va Nguyin Thi Hing Hanh, 2009) thi ning tich luy cacbon cua rimg ttam ttIn nen dit than biin Vudn quoc gia U Minh Thugng hoin toan kha thi Kit qui niy se giup ich duge nhilu cho nhOng cong frinh khoa hpc sau niy gidp cac nhi khoa hpc hoach dinh dugc kl hoach phat triln thi ttudng CO2 ttong tuong lai KET LU^N VA DE XUAT 4.1 Ket lugn Riing CO dp tuoi nhd hon 10 eo mat dp cay ldn hon rimg cd dp tuli Idn ban 10 Nguac lgi dudng kinh vi chilu cao cua rdng trim nhd hem 10 tudi nhd han so vdi rimg Idn ban 10 tudi Riiog trim nhd hon 10 tudi eo sl loai ciy bui hifn difn (9 loai) it hon so vdi rimg frim ldn ban 10 mdi (10 loai), nhin^ mat dp vi trpng Iugng Idn ban Trong say (Phragmites vallatoria (L.)Veldk.) vi choai ((Stenochlaena palustris (Burm) Bedd.) li nhdng loii chu yiu co m|t d0 cao Tdng sinh khoi khd cua rimg trim nho hon 10 tuli la 58,5 tin/ha; cdn d rimg ttim ldn hon 10 tuoi thi sinh khii kho dat 58,7 tin/ha Trung binh him lupng cacbon ti'ch luy cua rimg tram ed dp tuli nho hon 10 la 26,92 (tin C/ha) va rimg trim CO dp tuli ldn hon 10 li 26,05 (tin C/ha) 4.2 filxuit Qui trinh nghien edu chi xac dinh ham lugng cacbon tieh luy ttIn nin dit than bim De nghi cie nghien cuu tiep sau lim ro him Iugng cacbon tieh liiy ttong bp phgn rl cda ciy ttam va ci ham lugng cacbon tieh luy ttong dit Tu kit qua tinh toin duge eua