KHOA HOC CONG N G H i /l\IGHIEI\l CLriJ OAC DIEM TAI SIIXIH LO TROIVG RIJI\IG LA ROIVG THUdlVG XAIVH TAI VLTQIV QUOC GIA XUAIV 501\| Nguyin D ^ Tri&S Bin Thi D6i^ Phgm Minh Toai^ Ngd Thi Long'''' TOMTAT[.]
KHOA HOC CONG N G H i /l\IGHIEI\l CLriJ OAC DIEM TAI SIIXIH LO TROIVG RIJI\IG LA ROIVG THUdlVG XAIVH TAI VLTQIV QUOC GIA XUAIV 501\| Nguyin D ^ Tri&S Bin Thi D6i^ Phgm Minh Toai^ Ngd Thi Long' TOMTAT Dua ti^n ket qua nghian cuu tii 73 Id tidng cua cac trang thai rung la rpng tiiudng xanh tai Vudn Qudc gia Xuan Son da xac dinh dupc dien tich 16 frdng tnmg binh d cac trang thai rimg bien dpng ttr 112,4 m^ den 168,3 ml Ty le Id tidng co nguon gdc tir cay chet tu nhien va diSn tich nhd hon 100 m^ chiem uu thi Thanh phan loai cay tai sinh tai cac Id tidng rat phong phii va da dang, bien dong tu 43 den 85 loai, nhi^n chi co - loai CO mat cong thdc to loai Mat dp cay tai sinh biln dpng tir 8.800 den 12.533 cay/ha Ty le cay tai sinh co pham chat tdt, bien dong tu 77,3% din 86,7% va chu ylu co ngudn goc tir hat Ty 1$ cay tdi sinh trien vong (h>2,0 m) d cac 15tidngchiem tir 25,28% den 38,07% vdi su tham gia tu 29 den 54 loai, co 4-6 loai tham gia cong thiic td loai Su ke thira loai cay giira Idp cay tai sinh Id tidng vdi tang cdy cao xung quanh chilm ty 1& tir 36,2% den 67,1%; chi sd tuong ddng (SI) biln d6ng tir 0,45 den 0,61 Ddi vdi ldp cdy tdi sinh trien vong cua Idfrdng,ty le ke thira tir 25,7% din 52,9% va chi sd SI biln dong tir 0,35 den 0,60 Tir khda: Riing la rong thudng xanh tai sinh 16 tring, tai smh tirnhiSn + Tuyen 1: Xdm Dit - Xdm Lang - Lung Mdng 1.0ATVAN0E Tdi sinh rimg la mdt qud trinh sinh hoc mang tinh ddc thu cua h i sinh thai rimg Bilu hien dae trung cua tai sinh rimg la sir xuat hien mgt thi he cay etia nhung loai cay gd d noi edn hoan canh rimg (dudi tan rimg, Id tidng tiong rimg, rimg sau khai thdc, tiln dat rimg sau lam nuang ddt rdy ) Tdi sinh rimg d rimg tu nhien nhiet ddi thudng ed cdc hinh thiic chti ylu Id: (i) tai sinh liln tiic dudi tdn rimg vd (ii) tdi sinh Id trdng Tdi sinh Id tidng la sir mam va hinh thdnh cay ma, cay eon tiong cdc Id trdng dudi tan rimg ed sir xao tidn tu nhien hoac nhdn tde Tai sinh Id tidng phu thudc vdo kich thudc vd tang eay cao xung quanh 16 tidng, su phat trien eua cdy bui, tham tuai d Id tidng Vudn Qudc gia Xudn Son cd tdng dien tieh 15.048 vdi rimg la rdng thudng xanh chilm tm thi Mdt tiong eae nhiem vii tipng tam eua vudn la xae dinh duoc dpng thai tai sinh tu nhiin cua tham thuc vat rimg Do vay, dl tai tap trung nghien ciiu dac dilm tdi sinh Id tidng eua tham thue vdt Iam CO sd de xudt cae biln phap quan Iy vd phat trien bin vimg tai nguyen thuc vat rimg + Tuyin 2: Xdm Dii - Niii Ten + Tuyin 3: Xdm Du - Xdm L^p - Xdm Cdi + Tuyen 4: Xdm Du - Trung tam Vtron - Xd XuSn Dai + Tuyin 5: Xdm Lap - Ntii Bang - Lua chgn Id tidng: Cae Id tidng tu nhiin duoc lira ehgn khi: ed diln tich > 25 m^; da sd eae cay go tiong Id frdng cd chieu cao nhd hon m hodc chilu eao trung binh < 50% ehilu cao cua tang eay cao xung quanh; each Id trdng dugc lua chon trudc dd ^i thieu 50 m dl dam bao khdng trimg lap cdy cao xung quanh Id tidng Nghien euu da lua ehgn dupe 73 16 tidng tai frang thai rimg cua khu vuc nghien ciiu - Thilt lap tuyin dieu tia: Can cii ban dd hien trang rimg eua khu virc nghiin ciiu, xde dmh tuyin dilu tia, dam bao dai diln cho cdc tiang thai rimg cua khu vue Trong nghiin cuu xac dmh 05 tuyen: - Xdc dinh diln tich Id frdng, gdm budc: (i) budc 1: tir vi tri trung tdm Id trdng, sir dung la ban xae dinh diem thude mep Id tidng ndm tien goc phuang Vl 0^ 45", 90^ 135°, 180^ 225°, 270" vd 315" Danh dau vi tri cde dilm bdng cpc gd de thuan tien cho cdng viee dim tilp theo; (ii) budc sit dung thudc Vertex de xac dinh khoang each giiia dilm ndm tiln mep Id tidng va (iii) budc khoang each vudng gdc tir vi tri trung tdm Id tidng tdi doan thdng ndi cae dilm "phuang vi" tiln Dien tich ciia 16 tidng sau dd dugc xde dinh Id tdng diln tich cua hinh tam gidc ed dinh ehung ndm d tdm 16 frdng va edc dinh tuong iing vdi dilm thudc mep 16 tidng ^ Trudng D^ii hpc Hiing Vuong " Trudng Dai hpc Lam nghiep - Thiet lap d dang ban dilu tia tai sinh: Tai tmng tam Id tidng lap 01 d dang ban cd diln tich 25 m^ (5 X m) vd dieu tia tat ca cay tdi sinh theo cac chi tilu: PHUDNG PHAP NGHBU CUU 122 NONG NGHIEP VA PHAT TRIEN NONG THON - KY - THANG 10/2014 KHOA HOC CONG NGHfi loai cdy, chilu cao viit ngpn, dudng kinh gdc, chat lugng sinh tniong vd ngudn gdc - Dilu tra tang cdy cao xung quanh 16 tidng; Trin canh bin tiong dugc thiet ldp bdi "dilm phuong vi" dilu tra rdng ngoai 10 m vd dim todn bo cay cd Di > cm vdi cac chi tilu: lodi cdy, DL3, Hvn, Dt - Td thdnh tang cdy cao dugc xdc dinh cdn cti vao chl sd quan tigng (IVl) cua timg loai cay tiong quan xa tbyc vat theo phuong phdp cua Bruce va James (2002) can o i vao sd cdy, tilt diln ngang cua mdi lodi IVI,%: N , % + G,% Trong dd: IVIi% la chi sd dp quan tigng cua loai i frong quan xa thuc vat rimg; Nj%: mat dp tuong ddi ctia lodi i dugc tinh bang ty 1§ % giua sd ca thi cua lodi i vd tdng sd ca t h i tiong quan xd G,%: tilt diln ngang tuong ddi duge tinh bang ty ll % giiia tdng tilt diln ngang eiia lodi i vd tdng tilt diln ngang cua quan xa H§ sd td thdnh ciia mdi lodi (iheo phan 10) Ki = IVI%/10 - Xde dinh td thdnh lodi cdy tai sinh: Trong dix kj la h i sd td thdnh Ioai thti i; Uj Id sd Iuong cd thi loai thti i; N la tdng sd cd thi cua cac loai dilu tra dtroc - Chat lugng cdy tdi sinh dupc ddnh gia thdng qua cdc chi tilu hinh thdi ben ngoai vd phdn thdnh ba cap: Cay tdt, cdy xau, cay trung binh - Ngudn gdc cdy tdi sinh dugc phan bilt theo hai hinh tinic: Tdi sinh hat, tai sinh ehdi - Chieu eao cdy tdi sinh phan cap; m Danh gid triln vgng eua eay tdi sinh dira vdo chilu cao cua cay tai sinh, rthiing cay cd ehilu eao > m, ed pham chat tdt thi dupc coi la cdy tai sinh triln vgng - Danh gid khd nang k l thira lodi cdy cua Idp cay tdi sinh so vdi tang cdy cao, sti dung chi sd tuong ddng SI {Index of similarity hay Sorensen Indexi SI = C / ( A - H B ) Trong dd: C la sd Ioai xudt hiln d ca hai tdng cdy; A,B la sd Iugng lodi eua tdng cdy cao ( ^ , tang cdy tdi sinh (B) Nlu chi sd SI > 0,75 cd thi kit ludn thdnh phlu loai cua hai tang cdy cd mdi bin h i chdt che D l xdc dinh td thdnh cay tai sinh: dupc xde dinh KET QUii NGHBII CUU VA THAO LUAN theo sd cdy (N) vdi he sd td thdnh (theo phdn 10) cua cdc lodi tham gia theo edng thtic: A:, = ^ x l O ^ 3.1 Ddc dilm 16 trdng tdi khu vi^ nghiin cihi Dua tiln kit qua thdng k l tir 73 Id tidng rung la rdng thuimg xanh ctia khu virc nghidn ctiu, dae dilm CO ban cua Id tidng dupc thi hiln d bang B ^ D Jc dilm 16 trdng tai ichuvuc nghiin ciiu D^c diem S6 lugng 16 (73 16) IIB IIIAl Cilia tiieo nguyen niian iiinii tiianli 16 tr6ng - Do cdy chet do, thdn cdy da muc - Do cdy bi gio bdo f;dy do, chdt phd - Khong ro nguyen nhdn 1 Di?n ticil 16 tr6ng (m'') 112,4±48,4 143,8±88,3 - Dten tich 16 nho nhdt (m') 53,8 35 • Di4n tich 16 Irong ion nhdt (m^) 202 319 Kit qua d bang cho thjiy, tdng sd Id tidng dilu tia Id 7316, nhilu nhat d trang tiiai IV (18 Id) vd thap nhdt b trang thai IIB (8 Id) Trong nghiin ctru nay, nguyin nhdn hinh thdnh Id tidng gdm loai: 16 tidng dupc hinh cay dd tu nhien vd da mtie; Id tidng hinh thdnh cdy hi gid bao gay dd hodc chdt phd vd 16 tidng khdng rd lich sir hinh thdnh chilm ty I | thdp nh^L Trang thai rirng 11IA2 iIlA3 11 12 IIIB 15 IV 18 4 3 3 118,3±60,8 I37,9±78,7 i29,6±50,9 168,3±71,7 44,7 40 70 80 215 252,2 209,8 349 Diln tieh Id tidng ed su khac giiia cac tiang thai, cao nhat d tiang thai IV vdi diln tich trung binh 168,3 ± 71,7 m^; biln ddng tir 80 m^ din 349 m^; tiang thdi cd diln tieh 16 tidng thap nhdt Id IIB vdi diln tich trung binh 112,4 ± 48,4 m^ biln ddng tir 53,8 m^ din 202 m^ Nlu phan ehia theo diln tich 16 tidng, ty 1| 16 tidng cd di$n tich nhd han 100 m^, chilm 62,5% d N N G N G H I I P VA PHAT TRIEN NONG THON - KY - THANG 10/2014 123 KHOA HOC C N G NGHi trang a i a I B ; 44,44% a trang tliai niAl; 36,36% a trang thai IIIA2; 41,67% ff trang thai fflAB; 40% b trang thm IIIB va 11,11% a frang t h a IV Ty Ie 15 tring CO dl6n tich 100-150 m^ cao nhat trang thai IV (38,89%), thap nhat & trang thai IIIA3 (8,33%) Voi la CO dien tich 150-200 m^, ly Ie cao nhat b trang t h a IIIB (26,67%) va thap nhit b trang t h a IIIA3 (8,33%) Ty 16 16 co dita tich>200 m^ cao nhat a trang thai IIIAS (41,67%), thap nhat b trang t h a UB (12,50%) 3.2 Dac di^m tang c3y cao xung quanh 16 trdng 3.2.1 S^ luong vi mot so chi ti^u sinh tnidng ctia tang cay cao Xac dinh s6 lucmg va dac di^m sinh truong dia tang cay cao n h a n xac dinh miic a i h huong dia chiing den sinh truong v^ phdt tri^n ctia cay t a sinh b che 15 trong ning K^t qua nghien ctm dtroc the hien bang Baig So IIKmgvamStsocl]11ti^usmh tnionir cua tang cay cao H™(m) D,(m) Q(m") N (cay) Di.3 (cm) 8,0*2,0' 3,2*0,9" 12,4*4,3' 51,5±14,4' 12,9±1,5' 11,1*2,2° 3,5*0,8"° 41,3±16,0» I9,5±3,2° 21,9*7,3° T,i,5-tl\,6' 13,3*1,2' 3,7*0,5° 27,1*4,1° 24,0±3,2° 3,7*0,5° 23,9±0,7' 13,5*1,2° 30,8*5,6° 40,2*9,3° 3,8*0,4° 27,2*3,2" 14,0*1,2° 35,3±8,5'' 32,1*7,0° 4,0*0,4° 14,8*1,0" 35,0*8,0° 31,0*3,7° 37,4*8,5° rv Ket qua b baig cho thay, so luong cay cao Dt = 3,2*0,9 m, G - 12,4*4,3 nf, cao nhat o'trang thai xung quanh 16 CO sti khac biet gitia cac trang IV vol D I dat 31,0±3,7 cm, H „ - 14,8*1,0 m, D, t h a rimg, nhi^u nhat 6' trang t h a IIB (51,5*14,4 cay), 4,0*0,4 m, G dat 37,4*8,5 m' thap nhat o' trang t h a IV (35,0*8,0 cay) Voi trang 3.2.2 Cau tnic td tang cay cao xung quanh t h a rung nguydn sinh (IV), cay 6- ting cay cao co 16 kich thuoc nen c6 it cay hon b rimg phiic hoi (IIB) T a khu vuc nghifen ctiu, t6 thaih ctia taig cay Cac chi tieu sinh truong D13, H^^, Dt va G deu co su cao xung quanh 15 duoc xac dinh dua trgn s6 khdc biet ro ret 6' cac trang thm rimg, thap nhat b luong ca the, tong ti^t dien ngang Ket qua duoc till h-ang t h a IIB voi D, = 12,9*1,5 cm, H„ - 8,0*2,0 m, hien qua baig Baig T6 thaih ting ciy cao xtmg quanh 15 So loai Ty Ie loa TTR Ki Cong thtrc to thaih tm the uu die (%) TTR IIB IIIAl IIIA2 IIIAS Iim IIIAS 6,85 IV 70 7,04 1,23 Pma + 1,21 Bga -i- 0,63 Lv + 0,59 N n a + 0,52 Mro + 5,85 LK (64 loai) 0,75 Gt + 0,61 Lv -f 8,68 LK (72 loai) 0,56 Lv + 0,53 Mro -i- 0,53 Gt -i- 8,38 LK (69 loa) 0,65 Trm -> 0,57 Chv + 0,54 Gt + 8,32 LK (71 loa 0,91 GtH 0,75 Mro H- 0,66 Varu -1- 0,66 Lv -f 0,62 Chv + 6,50 LK ( loa) s 3,43 ^ 0,82 Sa * 0,68 Va -1- 0,63 Gt + 0,52 Sr -i- 6,57 LK (67 loa) Ghi chu: TTR Trang thai ning, K,: He so to cac loai cay cay uu the; Pma: Phin ma; Bga: Ba gac; Ix Loc vimg; Nnai: Niii nai: Mro: Mo roi; Gt: GO, triing; Trm: Trucmg mat; Chv: Chia vdi; Varu: Vai ning; Sx Sang; Sr: San ning; LK: Loai khac Ket qua t a baig cho thay, thaih phan loa taig roi Sang, Truimg mat, V a rimg, Chia v5i, Thanh cay cao xung quanh 16 frong o" cac frang t h a ning phin loa tang cay cao xung quanh 15 frdng co cac loai phong phti, da dang, bien dpng hi 69 loa (IIB) den 74 cay g6 gia tri nhu Gpi n^p, Tau mat Sen mat, Trai loa (IIIAl), mac dit so loa co mat o cac frang thai ly, Tuy nhten so lupng cita chiing khong nhi^u nta rimg lon nhung so loa co mat O' cong thtic to khong CO mat frong c6ng thtic td thaih loa loa rat thap, bien dong tir QIIAl) loa den loa OIB, 3.3 Dac didm tii sinh 16 trdng IIIB, IV), chiem ty le ttr 2,70% den 7,25% To loai cay CO su thay doi giUa cac frang t h a rimg, cac loa uu 3.3.1 Mat va mot s6'chi deu sinh tmdng cOa the gom: Phan ma, Ba gac, Loc vimg, Goi frang Mo cay iBi sinh NONG NGHIEP VA PHAT TRIEN NONG THON - KY - THANG 10/2014 KHOA HOC CONG NGHE Bang Mat vd mdt sd chi tidu sinh truong cua cdv tii sinh 15 trdnc TTR nB inAi mA2 mA3 IHB IV Mat (cay/lia) 8.800*4.350" 12.533*4.152' 10.873*3.495' 10.500*3.546" 11.040*2.836" 12.200*3.888° Duong kiob goc (Do, cm) 1,98*0,29' 1,54*0,45" 1,87*0,43" 2,01*0,42" 1,61*0,28° 1,73*0,42" Chieu cao (Hvn, m) 2,02*0,29" 1,59*0,42' 1,93*0,45" 1,97*0,40' 1,65*0,39' 1.79*0,53" Ghi chd- a, b Ii cac ky tu biiu thi miic dp dong nhi't, sai khac cua dai lupng quan sat dupc kiem tra bang tieu chuin One-way ANOVA vdi xac suit p < 0,05 Mat va eae chi tilu smh tmdng cay tai sinh Id tidng ciia cac tiang thai rung duge thi hiln d bang 3.3.2 Dp uu thi, muc dp da dang vi td thinh loii ciy tai sinh Id tidng Bdng Dd uu thd, dd da dang va td cay tai smh TTR Sd loai Cd H Ki Cong thtic td 2,39 Bga + 0,97 Mro * 0,80 Pma + 0,63 Snh + 0,57 Varu + 4,66 IIB 43 8,88 10,72 5,34 LK(38Ioa) 0,85 Mcln + 0,60 Gt + 0,57 Lv + 0,57 Smqui + 0,53 Lane + 6,28 72 3,44 21,08 3,79 IIIAl LK(661oa II1A2 70 3,45 20,69 1,71 0,94 Pma + 0,77 Smq + 8,29 LK (68 loa) 2,86 22,54 2,16 0,63 Smq + 0,51 Dpt + 0,51 Gt + 0,51 Pma + 7,84 LK (73 loa) IIIA3 75 IIIB 83 3,08 22,32 1,91 0,72 Mchi + 0,65 Lv + 0,53 Ddr + 8,09 LK (80 loa) 0,71Trm + 0,69 Varu + 0,66 C a + 0,55 Va + 0,51 Gt + 6,89 LK (80 IV 85 3,39 21,09 3,11 loa) Ghi chu Cd: chi sd da dang Snnpson (chi sd chiim uu the); H: Chf sd da dang loii (Shannon-Wiener index); Ki: H^ sd to tiiinh loii uu the; Snh: Sang nhung; Mcln: Mau chd li nhd; Smg: Sao mat qui; Lane: Li nen; Dpt: Dai phong tu; Ddr: Du du rung; CaJ: Ci Io; Va: Vinganh Kit qua d bang eho thay, phdn loai eay xac dinh pham chat ciia cay Ngudn gdc cay tai sinh tai sinh Id tidng eua khu vue nghiin cmi rat phong gdm hai hinh thuc la tai sinh hat va tai sinh chdi Kit phli va da dang, biln ddng tu 43 Ioai (IIB) din 85 qua xae dinh pham chat, ngudn gdc eay tai sinh Id loai (TV) Tuy nhien, sd loai cd mat tiong cong thue trdng dugc thi hien d bang Bang Phdm ehat va ngudn gde cdy tai sinh td Iai rat thap, biln ddng tir loai (IIIA2) din lo^i (IIB) Muc dd chiem uu thi (Cd), eao nhat d tiang thai IIB (8,88), thap nhat d trang thai IIIA2 (2,86) Trai nguoc muc dd chilm uu the la chi sd da dang loai (H) thap nhat d trang thai IIB (10,72) va cao nhat d tiang thai IIIAS (22,54) Thanh phan Ioai cay tdi sinh Id tidng cd su thay ddi giua cac tiang thai rimg, tiang thai rimg phue hdi IIB chu ylu la cae loai eay ua sdng Ba gae, Md roi, Phan ma, Vai rimg; ddi vdi cac tiang thai rimg IIIB, IV cac loai la: Ldc vimg, Mau ehd la nhd, Tnrdng mat, Vang anh chilm mi thi 3.3.3 Phim chit vi nguon gd'c ciy tii smh dudi tinning Phdm chat la chi tilu quan tiong de danh gia nang luc ciia cay tai va thi he rimg tiong tuong lai Trong nghiin euu nay, chi tilu hinh thai cay va kha nang sinh trudng eiia eay tai sinh dugc su dung dl TTR Nguon goc (%) Pham chat (%) Tdt T m n g binh Xau Hat Choi IIB 77,3 18,8 4,0 86,9 13,1 IIIAl 78,4 20,2 1.4 84,4 15,6 niA2 81,9 17,1 1.0 88.3 11.7 IIIAS 79,0 19,4 1,6 84,8 15.2 IIIB 86.7 12,1 1,2 90,3 9,7 rv 83,1 15,3 1,6 91,4 8,6 Kit qua d bang cho thay, ty le cay tai sinh Id tidng d cae trang thai rimg ed pham chat tdt kha cao, biln dong tir 77,3% GIB) den 86,7% (IIIB); ty le cay tai sinh cd pham chat trung binh biln ddng tir 12,1% (IIIB) den 20,2% (IIIAl); cay tai sinh cd pham chat xau chilm ty le rat thap, biln ddng tii 1,0% (IIIA2) din 4,0% GIB) Da sd eay tai sinh Id tidng cua cac trang thai rimg ed ngudn gdc tir hat, bien dgng tu 84,4% GIIAl) din 91,4% (TV); ty Ie cay tai sinh cd ngudn gdc tir chdi biln ddng tu 8,6% GV) din 15,6% GIIAl) N N G NGHIEP VA PHAT TRIEN NONG THON - KY - THANG 10/2014 125 KHOA HOC CONG N G H £ eooo.Oj 3.3.4 Phan body tii smh theo cap chieu cao Hinh cho thay, phan bd cay tai sinh theo cap chilu eao biln ddng rdt ldn giiia cac cap ehilu cao va trang thai rimg, ty l l cay tai sinh cd chilu cao nhd hon m chiem uu till, bien dgng tir 61,59% (MAS) den 74,82% (IDAI) Sd lirong cay tai sinh d tat ca cac tiang thai rimg deu ldn nhat d cdp chilu cao - m Dilu chting td ngudn hat gidng dugc phat tan din Id tidng rat Idn va dilu kiln eho hat gidng mam kha thuan lgi -•-IIB sooo-oj 4000.0 A -•-IIIAl / A \ -*-IIIAZ 3000.0 \ 2000.0 •• S^y ib*^ "*"" 1OOO.0 \ oj Ciy tai sinh ed ehieu cao >2 m duge eoi la ciy tai sinh trien vgng Ket qua xae dinh sd lugng va Hinh So s^nh phan bd sd cdy tdi sinh theo c ^ phan loai cay tai sinh trien vgng d Id tidng cac trang chilu cao dfcAc trgng t h ^ rimg thai rimg dugc till hiln d bang Bang Mat do, to thath loM cdy t ^ sinh tlifo vong 16 Cong thtic to thaih Ki TTR So loa N (cay/ha) Tyle(%) 1,79 Mro + 1,64 Bga + 0,75 Pma + 0,75 Snh + 5,07 LK IIB 3.350 38,07 4,93 29 (25 loa) 0,98 Lane + 0,98 M c b + 0,73 Lv + 0,61 Varu + 0,61 inAl 3,90 25,18 35 3.156 Voman + 6,10LK(301oa) 0,78 Dpt + 0,69 Gt + 0,69 Smq + 0,59 Gnep + 0,59 Rorg+ IIIA2 3.709 41 34,11 3,33 6,67 LK (36 toa) 0,74 Va + 0,58 Lv + 0,50 Cv + 0,50 Gt + 0,50 Lane + 0,50 IIIM 4.033 50 38,41 3,31 Smq + 6,69 LK (44 loa) 0,79 Varu + 0,71 Lv + 0,57 Dpt + 0,57 Mchl + 7,36 LK niB 55 3.733 33,81 2,64 (51 loa) 1,15 Varu + 0,63 Gt + 0,58 Va + 9,52 Dptu + 7,12 LK (51 IV 4.244 54 34,79 2,88 loa) Ghichii: Vmon: Vd min; Gnep: Gdi nep; Cv: Cudng ving; Rorg: Roi rung; LK Loii khic Bang F h ^ bd c£ly t ^ sinh ti-ln b l m | t ddt t^i Bang cho thay, phan loai c^y tai sinh cac Id tidng trien vpng d 15 tidng cua khu vue rat phong phii va da dang, biln ddng tir 29 loai (HB) din 55 Ioai GIIB); mat cay tai sinh triln vpng kha cao, tir 3.156 cay/ha (IIIAl) den 4.244 cay/ha (IV) So vdi mat dp cay tai sinh d Id tidng, ty l l cay tai triln vpng biln ddng tir 25,18% GIIAl) din 38,07% GIB) Sd loai ed mat tiong edng thiie td biln ddng 4-6 loai; Md roi, Ba gac, Roi rimg, Vai rimg, Ldc vimg La nin, Dai phong tu , la cac loai uu thi cua Idp cay tai sinh triln vpng 3.3.5 Phin biciy Id trdng tai sinh tidn be mit dit tai cic Dang phai bo 118,29 5,38 Cum 107,75 3,44 Cum 27±9"'' 76,36 2,81 Cura II1A3 26 ± * 78,57 2,99 Cum IIIB 27 ± * 50,26 1,82 Cum IV 30 ± ' 94,50 3,10 Cum \' IIB 22 ±11" inAi 31*10' IIIA2 Bang cho thay, sd lugng eay tai sinh trung binb tiong 16 tidng thude tiang thai nghiin cuu cd su Tir kit qua dilu tia tiln cae d dang ban 25 m^ tiong 73 Id tidng eiia 06 tiang thai rimg khu vue nghien cuu, phan bd sd cay tai sinh tien be mat dat tiong cac Id tidng theo chi sd Poisson dugc tdng hgp tiong bang 126 to n + SD (cay/ODB) TTR khac bilt cd y nghia, biln ddng tir 22 cAy/d (trang thai IIB) din 31 cay/d (tiang thai IIIAl) Cdc gid tri (0 eiia cac tiang thai rimg diu Idn hon 1, chiing to phan bd eiia cay tai sinh b cac Id tidng b dang cum NONG NGHIEP VA PHAT TRIEN NONG THON - KY - THANG 10/2014 KHOA HOC C O H G NGHi 3.4 Si; tuong d6ng Ccky t a sinh v6i ting cdy cao xung quanhl6tr6ng Being Su tuong done toa lop c ^ t ^ sinh (B) voi tang c ^ cao (A) quanh 16 ti^ng Chi so tutmg dong Ke thira C&A Ke Ihtra B&A s6loa TTR So loai Sdloa C A SIA&C B 0,39 0,45 36,2 19 27,5 UB 25 29 69 43 0,35 0,59 58,1 19 25,7 43 35 mAi 74 72 0,50 0,58 IIIA2 56,9 28 38,9 41 72 70 41 0,37 0,49 31,1 37 IIIAS 50,0 23 74 76 50 0,52 0,56 45,2 60,3 33 44 55 mB 73 83 0,60 0,61 37 52,9 IV 67,1 47 70 85 54 Ghi chd A- So loii tang ciy cao; B: Si loii ciy tii smh dudi Id tidng; C: Sdloii ciy xuit bien d ci hai tang % % cay Bang eho thay, su tuong ddng loai eay giua tdng cay cao va ldp cay tai sinh Id tidng thay ddi theo trang tiiai rimg vdi ty l l k l thira tu 36,2% (IIB) din 67,1% (IV) Tuy nhiin chi sd tuong ddng (SI) d cae trang thai rimg diu 2,0 m) chi ehilm tir 25,28% GIIAl) din 38,07% GIB) vdi mat dp tir 3.156 cay/ha (HIAl) din 4.244 cay/ha GV); phan lodi cay tdi sinh triln vpng khd phong phu, bien ddng tir 29 loai (IIB) din 54 loai QV) Phan bd cay tai sinh tien b l mat dat tai cac 16 tidng thudc dang phan bd cum Tu 73 16 tidng d rimg la rdng thudng xanh cua - Su tuong ddng (SI) lodi cay giira tang cay eao Vudn Qudc gia Xuan Son, nghien eiru da xae vd ldp cay tai sinh Id tidng thay ddi theo trang thdi dinh duge mdt sd dae dilm eo ban cua tai sinh Id rung vdi ty le k l thua tir 36,2% GIB) din 67,1% (TV) tidng: Chi sd SI d muc trung binh, tir 0,45 (IIB) din 0,61 - Diln tieh Id tidng ed su khac giiia cac GIB) Ddi vdi ldp cay tai sinh triln vong cua 16 tidng trang thai, trung binh tu 112,4 m^ GIB) den 168,3 m^ cd ty 11 ke tiiiia bien ddng tir 25,7% GIIAl) din 52,9% (IV) Ty ll Id tidng cd diln tich nhd hon 100 m^ eao GV) va ehi sd SI biln ddng tir 0,35 din 0,60 nhat d tiang thai IIB (62,5%), thap nhat d tiang tiiai Vdi nhung dac diem tai smh Id tidng neu tien, cd rv (11,11%); ty Ie Id tidng cd dien tieh >200 m^ cao the thay rdng, d rimg la rdng thudng xanh Vudn nhat d tiang thai IIIA3 (41,67%), tiiap nhat d tiang Qudc gia Xuan Son, qua trinh tdi sinh Id frdng dang tiidi IIB (12,50%) Ld tidng hinh cay chet tu diln khd thuan lgi d hau h i t cdc tiang thai rimg nhien, than cay da muc ehiem mi the, eao nhat d Tuy sir ke thiia ciia ldp eay tdi sinh k l can edn d muc tiang thai IIB (62,5%), tiiap nhat d tiang thai IIIA3 trung binh nhung dilu la phii hgp vdi thue t l bdi (33,3%) tai Id tidng, nhieu lodi cay ua sang cd thi phat triln - Mat dp cay tai sinh 16 cua cae trang thai rimg tdt hon Tuy nhien, tiong tuong lai sir tuong ddng d rat ldn, biln ddng tir 8.800 eay/ha GIB) din 12.533 hai tang cay se din duoc tang len Do vay, can cay/ha GIIAl) Dudng kinh gdc cay tai sinh 16 tidng bao vl tdt tai nguyin rimg noi day va tiep tue theo cua cae tiang thdi rimg cd su khae bilt, cao nhat d ddi qua trinh phat tnen eua ldp cay tai sinh d cac 16 tiang tiidi IIIA3 (2,01 cm) va tiiap nhat d tiang thai tidng tiong rimg IIIAl (1,54 em), ehilu cao trung binh eay tai sinh Id TAI LEU THAM KHAO tidng chua cd su khde bi^t giua cac tiang thai rimg Tran Van Con va edng su, 2010 Ngbien cuu - Thanh phin loai cay tdi sinh Id tidng cua khu cic die diem lim hoc (diin thi, ciu tnic, to thinh virc nghiin cuu rat phong phu va da dang, biln ddng N N G NGHIEP V A PHAT TRIEN NONG THON - KY - THANG 10/2014 127 KHOA HOC CONG N G H t tai sinh (TS), tang truang, hau thuy van, dat, ) cia mot so he sinh thai rimg (HSTR) til nhien chu yeu a Viet Nam Bao cao tdng ket de tai Vita tiah Ninh Binb Luan van tdt nghigp d a hoc Dai hoc l A n nghigp Ha Noi u, Q^^ ^^^ 2009 Phuang phap nghiin aht KHLNVN, 2010 pjj^ Le Thi Dien, Pham Mmh Toai, Le Phti Anh, 2010 Nghiin ctiu dac diem tai sinh loai Re huang (Cinamomum parthenoxylon) tai Vucm Qudc gia Bach Ma Tap chi Khoa hoc - D a hoc Hu«, sd 63, 2010 fti 33-411 o ^T-^£ TT- ^ iAôi ^T' A' A-& *'ã ã u ' Vu Tiln Hmh, 199L Ve dac dilm tai smh eua ^ ~ rL - / ^ «fl^ rung ttr nhien Tap san Lim nghiep (so 02) Tap chi Khoa hoc Lan nghiep Vita Khoa hpc Iim nghigp Ha Ndi ^ -n.-TTU onnn Ar t - „., Nguyen Th, Kha, 2009 Nghien cm die diSm ^ * ^ ^^ vi dudi tan tiang tiiii rung IIIAl tai Cong ly Lam nghiep Mai Son, huy0n Luc Nam tinb „ - „ , ,, IL i_ i Bac Giang Luan van thac sy khoa hoc lam nghiep *^ Trudng Dai hpc Lam nghiip Nguyin Thi Nhan, 2009 Nghidn cmi dac diem tii sinh IS tidng rimg Ui nhien Ii rdng tiiuong xanh tai Vudn Quoc gia Ciic Phuong, huyen Nho Quan, ^^^ , g ^ luang cac chi so da dang sinh hoc 7- '^^ ^ ^ ^rung, 1978 Thim tiiuc vit rimg VietNam NXB Khoa hpc Ky ttiuat Ha Ndi RESEARCH ON GAP REGENERATION CHARACTERISTICS OF BROAD LEAF EVERGREEN FORESTS IN XUAN SON NATIONAL PARK Nguyen Dac Trien, Bui The Doi, Hiam Minh Toai, Ngo TTie Long Summaiy The study results of 73 gaps in the broad leaf evergreen forest states of Xuan Son National Park determined that mean gap areafluctuatedfrom 112.4 m^ to 168.3 m^ Gaps derived from naturaUy dead frees and those with the area under 100 m^ were dominant The free regeneration composition in gaps was diverse, ranged from 43 to 85 species; however, there were only from to species appearing in the free species composition formula Regeneration density ranged from 8,800 stems/ha to 12,533 stems/ha The rate of good quality regenerating frees was from 77.3% to 86,7% and they were mostly originated from seed Ihe rate of advanced regeneration (height > 2.0 m) in gaps accoimted for from 25.28% to 38.07% of overall regeneration density, with from 29 to 54 in species richness and from to species appearing in the free species composition formula The regenerating free species richness in gaps was from 36.2 to 67.1 percent similar to the canopy free species richness in surroundings, and the similarity index fluctuated from 0.45 to 0.61 For the species richness of the advanced regenerating free layer in gaps, this similarity wasfrom25.7% to 52.9%, and the similarity index ranged from 0.35 to 0.60 Keywords: Broadleafevergreen forest, gap regeneration, natural regeneration Ngudi phan biln: PGS.TS Vd DEU Hai Ngdy n h ^ bdi: 18/8/2014 Ngdy tiidng qua phan biln: 19/9/2014 Ngdy duyit dang: 26/9/2014 128 N O N G NGHIEP V A PHAT TRIEN N O N G THON - KY - THANG 10/2014 ... tdi sinh dugc phan bilt theo hai hinh tinic: Tdi sinh hat, tai sinh ehdi - Chieu eao cdy tdi sinh phan cap; m Danh gid triln vgng eua eay tdi sinh. .. chi ti^u sinh tnidng ctia tang cay cao Xac dinh s6 lucmg va dac di^m sinh truong dia tang cay cao n h a n xac dinh miic a i h huong dia chiing den sinh truong v^ phdt tri^n ctia cay t a sinh b... eay xac dinh pham chat ciia cay Ngudn gdc cay tai sinh tai sinh Id tidng eua khu vue nghiin cmi rat phong gdm hai hinh thuc la tai sinh hat va tai sinh chdi Kit phli va da dang, biln ddng tu 43