SINH KHOI V A CAC BON CUA RUNG LA R 0N G THUOIXIG XANH VUNG TAY NGUYEN, V lfT NAM

Bdo Huy1, V6 Hung, Nguyfen Thj Thanh Huong, Cao Thj Ly, Pham Tuin Anh, Huynh NhAn Tri, Nguyfen Due Djnh

t 6m t AtTrtn ca so nghidn cuu ciu true sinh khdi, cic bon theo cip kinh cua kidu rung la rpng thuong xanh vung Tiy Nguydn cho tung don vj phin lo i li cip chidu cao va cip sinh khdi, trong do cac lim phin dupe chia thinh ba cip chidu cao vi ba cip sinh khoi (Cip 1: 99 tin/ha, cip 2: 222 tin/ha, cip 3: 331 tin/ha), t$o thinh 16 hpp 9 don vi phin loai dd xic djnh sinh khdi vi cic bon lim phin; dong thoi ting dung cic mo hinh sinh trie uoc tinh sinh khoi vi cic bon ciy ci thd di uoc tinh dugc cho cic lim phin voi lugng cic bon tich luy thip nhit trong ciy gd trdn mit dit li 47,84 tin/ha, trong ciy go dudi mit dit li 6,20 tin/ha vi tong cic bon trong ciy gd trdn vi dudi mit dat li 54,04 tin/ha; lugng cic bon tich luy cao nhit trong ciy gd trdn mit dit li 163,71 tin/ha, trong ciy gd dudi mit dit li 15,60 tin/ha vi tong cic bon trong ciy go trdn vi duoi mit dit li 179,31 tin/ha. Ting truong cua lim phin, vd sinh khoi thip nhit cua ciy go trdn vi duoi mit dit li 3,63 tin/ha/nim, cic bon trong ciy g6 trdn vi duoi mit dit li 1,67 tin/ha/nim vi hip thu C02 cua ciy gd trdn vi dudi mit dit li 6,13 tin/ha/nim; trong khi d6 ting truong cao nhit voi sinh khdi cua ciy gd trdn vi dudi mit dit li 9,84 tin/ha/nim, cic bon 4,40 tin/ha/nim vi hip thu C02 li 16,15 tin/ha/nim.Tirkhda: C ic bon rung, md hinh sinh trdc, rung li rqng thudng xanh, sinh khoi, TiyNguyin.

KHOA HQC C6N0 UGH*

i . b At v a n b £

Vin dfe uoc tinh sinh khoi, trir lugng cic bon rung luu giu vi lugng C02 hip thu hoac phit thai trong qui trinh quan ly rung de? tham gia chuong trinh REDD* (Reducing Emissions from Deforestation and Forest Degradation: Giam phit thii tir suy thoii vi mit rung kfet hgp vdi bao tdn, quin ly bfen vung rung vi ting cudng tru lugng cic bon rung d cic nude dang phit trifen) d Vifet Nam li m$t nhu ciu cip thifet, nhim cung cip thdng tin du lifeu hip thu vi phit thai C02 tu quan ly rung ding tin ciy theo yfeu ciu cua IPCC (2006), tu d6 c6 thfe xic djnh tin chi cic bon rung vi thu duge nguon tai chinh tu dich vu moi trudng hap thu C02 tir rimg.

Rimg c6 5 bfe chua cic bon (IPCC, 2006): Trong thuc vSt trfen mit dat, rfe ciy dudi mat dat, tham muc, ciy chfet vi cac bon huu co trong dat. Bfe chua cic bon cin dugc tap trung quan ly, giim sit li trong thyc v$t trfen m$t dat Dfe udc tinh sinh khoi cua ciy rung phin trfen mat dat (AGB) cho mot sd kifeu rimg nhifet ddi, phuong phip chat ha ciy (destructive sampling) vi lip md hinh sinh trie (allometric equations) dfe udc tinh sinh khdi, cic bon rimg di dugc thyc hifen bdi Brown (1997 - 2001), MacDicken (1997), Chave vi cdng sy (2005), Pearson (2007), Basuki vi cdng sy (2009), Henry vi cdng sy (2010), Dietz vi cdng sy (2011), Johannes vi cdng sy (2011).

1 Trudng D?i hoc Tiy Nguyen

Tuy nhifen sd lifeu ciy chat ha cdn it trdn vimg nhifet ddi rpng ldn toin ciu, chua c6 du lifeu dai difen cho rung nhifet ddi Vifet Nam vi chua dugc dinh gii sai sd vi dg tin ciy, do vay chua thfe ung dung d Vifet Nam. Ddng thdi kfet qui cua cic nghifen cuu niy chi mdi dimg lai d sinh khdi ciy c i thfe; cic gii trj sinh khdi, cic bon lim phin trfen mat dit chu yfeu dugc chuyfen ddi tir tru lugng rung go sang do dd cd dp tin ciy thap; trong khi dd thifeu cic mo hinh, phuong phip dfe udc tinh sinh khdi, cic bon cho cic lam phin khic nhau.

2. Bdi TIIQNG VA PHUONG PHAP NGHBV CUU

2.1. Ddi tugmg nghifen cuu- Sinh khdi vi cic bon ciy rimg: Bao gdm trong

5 bg phan li thin, cinh, li, vo vi rfe.- Sinh khdi vi cic bon lim phan: Sinh khdi vi bfe

chua cic bon trong ciy go cua lim phin trfen vi dudi mat dat

- Kifeu rung li rong thudng xanh bao gdm cic trang thii giiu, trung binh, ngheo vi non.

22. D$c difem khu vyc nghifen cuuCic khu rimg nghifen cuu nim trong khu vyc

phin bd dai difen cua rimg li rdng thudng xanh d 3 tinh Tiy Nguyfen li Gia Lai, Dak Lak vi Dak Ndng. Huyfen lCBang thupc tinh Gia Lai, hai huyfen Krong Bdng vi M’Drak thudc tinh Dik Lak vi huyfen Tuy Due thupc tinh Dik Ndng. Bao gdm 09 lo i dat trfen 03 loai di m? bazan, macma axit vi phifen sfet; dit cd kfet von nhe 0 - 20%, pH - 5,7 - 7,5, dp siu ting dit >

NONG NGHlfP VA PHAT TRIEN NdNG TH6N-KY1 + 2 - THANG 2/2014

KH NOHt

50 cm. G cac vj tri sucm vk dinh voi do doc 0 - 36°, trong pham vi do cao so voi mat bifen tir 376 m dfen1.068 m. Lugng mua binh quan nam 1.750 mm -2.500 mm/nam; c6 hai mua mua, kho, mua mua thuong tir thang 5 dfen thang 11; nhtet do trung binh nam bifen dong 22,2 - 27,0°C. Do am khong khi trung binh nam 80 - 83%.

2.3. Phuong phap nghidn cuu2.3.1. Thiit lap o miu dSdo tinh chi tieu lam phan0 mau dugc thifet lap theo phuong phap dai didn

cho cac trang thai rimg. 0 mau co kich thuoc 20 x 100 m, co 20 o m&u d 4 trang thai rimg dugc thtet lap; moi trang thai binh quan c6 5 o. Bo tri o theo phuong phap difen hinh va dugc rai dfeu theo cac cap tru lugng, sinh khoi. Moi o miu dugc phan chia thanh cic o phu theo cip duong kinh do dfem (ICRAF, 2007) 6 hinh 1.

cay rimg (ICRAF, 2007)Cac chi tidu difeu tra trong o mau bao gom loai,

duong kinh ngang nguc (DBH), chteu cao (H), phim chit cay. Phan chia thinh cic o phu theo cap kinh nhu sau:

- 6 miu chinh: 20 x 100 m: Difeu tra ciy go co DBH > 30 cm.

- 6 miu phu: 5 x 40 m (1 o trong o chinh): Difeu tra ciy go c6 5 cm < DBH < 30 cm;

- 0 mau phu: 5 x 5 m (1 o phu trong o chinh): Difeu tra cay go c6 DBH < 5 cm.

2.3.2. Phuong phdp uoc tinh sinh khoi, cdc bon ldm phdn

Cic lam phin li rgng thucmg xanh d Tiy Nguyfen phin bd r0ng trfen cac difeu kifen khic nhau, do d6 khi ndng san xuit sinh khoi vi tich luy cic bon cung khic nhau. Dfe uoc lupng dung tru lugng cic bon vi tang trudng cua n6 cin phan chia lim

phin thanh cac cip chifeu cao. Su dung md hinh tuong quan H -f(DBH) chung dfe phan chia thinh cac dudng cong chifeu cao thfe hifen cho ndng suit Trong nghifen cuu nay da phan chia thinh 3 cipchifeu cao.

Ngoai ra cac lam phin da qua tac ddng cic muc do khac nhau do d6 tich luy sinh khdi va d c bon vi dac difem ciu true cung thay ddi theo. Do d6 cin phan chia rimg thanh cic cip kinh khdi. Phan chia lam phin thanh 3 cap sinh khdi dua vao bifen ddng cua n6 vdi muc y nghia 95%.

Ciu true sinh khdi, cic bon lam phin dugc nghifen cuu theo cip kinh d 9 td hgp bao gdm 3 cipchifeu cao vi 3 cip sinh khdi.

Su dung cic mo hinh sinh trie dfe udc tinh sinh khdi vi cic bon ci thfe cay go da dupe Bio Huy vi cgng su (2012) thifet lap theo phuong phip chit h? cay tifeu chuin (destructrue measurement). 362 ciy tifeu chuin dugc chat ha rii dfeu theo cip kinh, phin bd theo cic loii phd bifen, uu thfe trong lam phin vi dai difen cho ba cip khdi lupng thfe tich g5 li cung, trung binh vi mfem dugc xic djnh nhanh d thyc dia. Cic md hinh udc tinh gdm cd: Sinh khdi cay gd trfen mat dit (AGB) (bao gdm c i 4 bd phin than, cinh, li vi vo), cic bon trong ciy gd trfen mat dit (C(AGB)), sinh khdi cay go dudi mit dit (trong rfe) (BGB), cic bon trong rfe cay gd (C(BGB)).

Sir dung phan bd thuc nghifem sd cay theo cip kinh (N/DBH), tuong quan H/DBH cho timg cip chifeu cao va cip sinh khdi; cimg vdi cic md hinh sinh trie udc tinh sinh khdi, cic bon ciy c i thfe ndi trfen; tinh toan dugc tdng sinh khdi vi cic bon lim phin trfen vi dudi m$t dit theo cip lrinh vi chung lim phin cho timg td hpp cip chifeu cao vi sinh khdi

Dfe du bio tang trudng sinh khdi vi cic bon lim phin, thifet lip md hinh quan hfe tudi A - f(DBH, H) dfe xic djnh A theo timg cip kinh vi tu kfet qui xic djnh sinh khdi vi cic bon cung theo cip lrinh, tinh dugc lupng tang trudng binh quin hAng nam vfe gjah khdi, cic bon theo cip kinh vi chung cho lam phin vi cho 9 td hpp sinh khdi - cip chifeu cao.

LrfTHAvAilAlUMN3.1. Phin cip chifeu cao dfe udc tinh «*nl» khdi,

cic bon lim phinCung nhu udc tinh tru lupng gd, dfe udc tinh sinh

khdi vi cic bon lim phin trudc hfet dto phan lo?

196 N6NG NGHlfP VA PHAT TRI N N6NG THON - KY 1 + 2 - THANG 2/2014

KHOA HOC C6NG NOHt

rung thinh nh6m ddng nhit vfe dp nang suit. Trong thuc tfe vifec u6c lupng sinh khdi, cic bon sfe mle sai sd cao khi chi dua vio mot nhin to ducmg kinh (DBH), vi cung DBH nhung ddi£u kifen lap dja thuan lgi, tdt hon thi chi£u cao (H) sfe cao hon va ngupc lai, do dd bifen s6 cua ham allometric equations (phuong trinh tinh tuong quan sinh truong) cd dp tin cay cao thudng phai c6 bifen chteu cao (H). Vi vay phan cip H dir<TC hi£u nhu la phan dp nang suit rung sfe hd trp cho vifec udc tinh sinh khoi, cac bon rung c6 do chinh xic cao hon.

Tu 241 cap sd lifeu H/DBH do trfen tit ca 6 miu nghifen cuu thuoc rung la rong thuong xanh Tay Nguyfen, thidt lap md hinh quan hfe H/DBH vdi cic tifeu chuin lua chpn ham nhu sau va bifeu thj d hinh 2:

H - 4DBH)H_m - (0.799577 ♦ 1 05918*ln(DBH_cm)r2

DBH_cm

Hinh 2: Quan hfe H/DBHH_m = (0,799577 + l,05918*ln(DBH_cm))A2 (1)Vdi R2 = 77,76%, P< 0,000, n = 241, CF = 1,07, AIC

«- 483,8 vas% = 16,7%.Tir md hinh H/DBH, tidn hanh phan chia thanh

3 dp chidu cao. Can cu vao bidn ddng chidu cao 13 - 25 m d dp dudng kinh 20 - 30 cm, su dung phuong phap c6 djnh tham sd a va thay ddi tham so bi theo timg dp H, tu day x4c djnh dupe cac phuong trinh giua va gidi h?n d c cap:

H_m « (0,799577 + bi*ln(DBH_cm))A2Tir day l$p dupe dudng cong va bifeu theo 3 cip

chidu cao cho rimg thudng xanh Tay Nguyfen d hinh 3.

Trfen cor sd cip H da l|p, m0t lam phdn cy thd nghifen cuu dupe xic djnh cip H tuong ung thdng qua H binh quan d cip kinh 20 - 30 cm, lam co sd udc lupng sinh khdi lam phin theo tung cip chidu cao.

Hinh 3: Dudng cong va bidu dp chidu cao3.2. Phan dp sinh khdi dd udc tinh d c bon lam

phinLam phin trong thuc tfe da qua cic muc dp tac

ddng khac nhau, do dd da cd thay ddi d c bon trong d c bfe chua, vi vay can phan chia thanh cac cip tuong ddi dong nhit vfe sinh khdi, nd khdng chi phin anh sinh khdi theo dp ma cdn dimg dfe lam ddi tupng ddng nhit cho vifec nit miu do tinh d c bon trfen thuc td. Chi tifeu sinh khdi lya chpn dfe phan cip la tdng sinh khdi cua tit ca cay go trfen m$t dit (than, dnh, la va vd) vdi DBH > 5 cm.

Trfen co sd du lifeu do dfem trong d c d miu, sip xdp phan bd N/DBH, su dyng quan hfe H/DBH theo timg cap H va dua vao ham sinh khdi d y trfen mat dit (AGB) vdi hai nhan td DBH va H dd udc tinh sinh khdi theo cip kinh va tdng sinh khdi cay gd trfen mat dit (TAGTB, tln/ha) cho timg lam phin.

Md hinh sinh trie udc tinh sinh khdi cay ca thd trfen mat dit (AGB) theo hai nhan td DBH va H dupe su dung theo Bao Huy va cong su (2012):

ln(AGB_kg) = -2,9766 + 0,535797*ln(DBH_cm) +0,759321*ln (H_m*DBH_cmA2) (2)

Kdt qua cho thiy sinh khdi TAGTB trung binh cua rimg 11 rpng thudng xanh vimg Tay Nguyfen la205,4 tln/ha, nhd nhit 11 34,4 tln/ha va ldn nhit la 364,3 tln/ha. Udc lupng TAGTB vdi dd tin cay 95%: TAGTB = 205,4 ± 49,0 tin /ha * 156 - 254 t!n$a.

Tidn hanh phan chia TAGTB thanh 3 dp d bang1 theo nguyfen tic cap 2 cd gia trj trung binh va bidn dong cua nd trong pham vi tin d y P *95%; dp 1 la cap sinh khdi thip, nim d pham vi trli bfen ngoai udc lupng khoang 95% va d p 3 la d p sinh khdi cao nim vd phia phai bfen ngoai cua udc lupng khoang 95%. Kdt qua dinh gii cho thiy phan chia thanh ba d p sinh khdi cd sy khic bifet rd rfet d muc tin cay 95%,

NONG NGHlfP VA PHAT TRllN NdNG TH6N-KY1 + 2 - THANG 2/2014

KHOA HQC C6HO NOH>

F = 69,98 > F(oo5, 2.17) = 3,59; P < 0,000. Nhu vay vi c la ty 1 sinh khoi ciy go trtn m$t dit cua lim phdn phin chia cap sinh khoi cho rung la rong thucmg (TAGTB, tin/ha) vdi tong tru lupng ciy dung (M, xanh li thich hgp, chung co su khac biet nhau dl tao m3/ha): BCEF - TAGTB / M; tu diy c6 thi suythinh timg khoi dong nhat trong do tinh, uoc lupng vi giam sit cic bon rung.

Trong thuc tl lam nghidp hten nay thucmg su dung gii tri tru lupng lim phan de phin chia trang thai rimg theo muc do giiu ngheo khic nhau. Dl thuan ti£n cho vi|c chuyln doi tir tru luong sang sinh khoi vi ngupc lai, tinh toin hi so chuyln doi BCEF

ngupc lai M * TAGTB/BCEF. Kit qua nhin dupe h| so BCEF rimg li rong thudng xanh vimg Tiy Nguyen trung binh li 0,707, voi do tm ciy 95% thi uoc lugng khoang BCEF - 0,707 ± 0,006. Trtn co sd do co dupe bang phin chia 3 cap sinh khdi cimg vdi gii trj tru lupng rimg tuong duong d bang 1.

Bing 1: Phin cdp sinh khdi TAGTB vd quan h£ vdi M

Cap sinh khoi TAGTB tan/ha) M (m3/ha)Min Max Min Max

Cap sinh khoi 1 35 155 50 220Cap sinh khoi 2 156 254 221 360Cap sinh khoi 3 255 365 361 5153.3. Sinh khdi vi cic bon tich lGy cua cic lim

phin trtn vi dudi m$t ditSinh khoi vi cic bon rimg dupe udc tinh dua vio

cau true sinh khoi vi cic bon ciy rimg theo cap kinh, cu ly cap 10 cm vi dupe udc lugng theo timg don vj phin chia lim phan li cip sinh khoi (co 3 cip) vi cdp chilu cao H (co 3 cap).

Trtn co sd sip xlp cic o nghten cuu theo timg cip sinh khoi vi cap chilu cao, tinh toin:

- Phin bd N/DBH cho timg don vi cap sinh khdi vi cap H.

- Su dung phuong trinh H/DBH cho timg cip chilu cao dl xic djnh H theo cip kinh

- Su dung cic mo hinh sinh trie cua Bao Huy vi cong su (2012) dl tinh sinh khoi/cic bon trtn vi dudi mit dat trung binh cho timg cip kinh.

ln(AGB_kg) = -2,9766 + 0,535797*ln(DBH_cm) +0,759321*ln (H_m*DBH_cmA2) (3)

ln(C(AGB)_kg) - -3,72664 + 2,05141*ln(DBH_cm) + 0,760168*ln(H_m) (4) BGB.kg * exp(-3,73687 + 2,32102*ln(DBH_cm)) (5)

C(BGB)_kg - exp(-4,91842 + 2,41957*ln(DBH_cm)) (6)

- Kit hpp vdi mit d$ theo cip kinh d l tinh tdng sinh khoi ciy g6 trin mit ddt CTAGTB, tan/ha), dudi mit dat (TBGTB, tdn/ha), tdng cic bon ciy g6 trin mit ddt (TAGTC, tdn/ha), dudi m it ddt (TBGTC, tan/ha) vi tdng sinh khdi ciy rimg trtn vi dudi m$t dat TTB (tdn/ha), tdng cic bon ciy rimg trtn vi dudi mit ddt TTC (tdn/ha).

Kit qua tinh toin dupe cdu true sinh khdi, cic bon lim phdn theo 3 cdp sinh khdi vi 3 cdp chilu cao, tao thinh 9 to hpp don vj phin chia sinh khdi/cic bon rimg. Kit qua minh hoa cdu true sinh khdi, cic bon cua lim phdn cd sinh khoi vi ning sudt trung binh: Cap sinh khoi 2 - Cap H la II (bang 2, hinh 4).

Bang 2: Cdu true sinh khdi vi cic bon d lim phdn cdp sinh khdi 2 — cdp HIIDBH(cm) H (m) N/ha TAGTB

(t/ha)TBGTB(t/ha)

TAGTC(t/ha)

TBGTC(t/ha)

TTB(t/ha)

TTC(t/ha)

5 6,7 878 5,2 0,9 2,4 0,3 6,0 2,715 14,4 479 48,2 6,1 22,6 2,5 543 25,125 19,0 208 74,0 8,7 34,7 3,7 82,7 38,435 22,4 47 37,7 4,3 17,7 1.9 42,0 19345 25,1 30 44,3 4,9 20,7 2,2 49,2 22,955 27,4 11 25,9 2,9 12,1 13 28,8 13,465 29,3 4 14,8 1.6 6,9 0,7 16,4 7,775 31,1 3 12,5 1.4 5,9 0,6 13,9 6385 32,6 2 11,3 U 53 0,6 12,5 5,9

Tong 1662 273,8 32,0 128,3 13,8 305,9 142,1

198 NONG NGHlfP VA PHATTRI^N N6NGTHON- K Y 1 + 2 - THANG2/2014

KHOA HOC C6NG NOHt

45.040.0

35.0

30.0

25.0

20.0

15.0

10.0

5.0u .u

5 15 25 35 45 55 65 75 85

■ T A G T C (t/ha) 2.4 22.6 34.7 17.7 20.7 12.1 6.9 5.9 5.3

■ T B G T C (t/ha) 0.3 2.5 3.7 1.9 2.2 1.3 0.7 0.6 0.6

Hinh 4: Phdn b6 sinh khdi trfen vd dudi m$t ddt theo cdp DBH lim phdn dp sinh khdi 2 - cdp HIITir ddy uric tinh dupe cdc bon tich luy trong ldm hgp phdn loai) theo bang 3.

phdn theo 3 cdp sinh khoi va 3 cap chidu cao (9 toJdng 3: Tich lfiy cdc bon ldm phdn trfen vd dudi mdt di t theo td hpp 3*3 (3 cdp sinh khdi * 3 cdp chidu cao'

Cdp sinh khdi / TAGTB (tdn/ha)

Tich luy C ldm phdn trfen vd dudi mdt ddt

Cdp HI II III

135-155 (tdn/ha)

TAGTC (tdn/ha) 66,23 57,27 47,84TBGTC (tdn/ha) 6,20 6,20 6,20TC (tdn/ha) 72,43 63,47 54,04

2156 - 254 (tdn/ha)

TAGTC (tan/ha) 148,56 128,33 107,04TBGTC (tdn/ha) 13,79 13,79 13,79TC (tan/ha) 162,35 142,12 120,83

3255-365 (tan/ha)

TAGTC (tdn/ha) 163,71 140,69 116,53TBGTC (tdn/ha) 15,60 15,60 15,60TC (tim/ha) 179,31 156,29 132,13

Nhu vdy doi voi rimg la rpng thudng xanh vimg Tdy Nguyfen xdc djnh dugc lupng cdc bon tich luy thdp nhat d cip sinh khdi 1 vd cap H III, voi cdc bon trfen m$t dat ld 47,84 tan/ha, duoi mdt dat ld 6,20 tdn/ha vd tdng ld 54,04 tan/ha; lupng cdc bon tich luy cao nhdt d cdp sinh khdi 3 vd cap H I, vdi cdc bon trfen mdt ddt la 163,71 tan/ha, dudi mdt dat ld 15,60 tdn/ha vd tdng 1a 179,31 tan/ha.

3.4. Dy bdo tdng trudng sinh khdi, cdc bon vd hdp thy C02 cua ldm phdn

Dy bdo dugc kha ndng hap thy C02 cua rimg rat cd f nghia trong theo doi bidn ddng lupng C02 khi tham gia chuong trinh REDD*. Hidn nay theo IPCC (2006) chu ydu cd hai phucmg phdp gidm sdt thay ddi bd chua cdc bon vd h > thy/phdt thai C02 rimg. Dd

la phuong phdp theo doi tdng thfem hodc mdt di cua cdc bon rung (Gain - Loss method) hodc phuong phap thay ddi tru lupng cdc bon tad cdc thdi didm (Stock Diference method). Cac phuong phdp ndy hodc 1a can theo doi thudng xuyfen trfen d djnh vj hodc do tinh rimg d cdc thdi didm vd tinh todn lai lupng cdc bon.

Nghifen cuu ndy nhdm chi ra dupe tdng trudng cua sinh khdi, cdc bon vd lupng C02 hap thu hdng ndm cua cac ldm phan khde nhau ldm co sd cho vide du bdo tdng trudng sinh khdi, cdc bon vd C02 hap thu khi rung chuydn tir cap sinh khdi ndy sang cap khac a timg cap chidu cao.

Trfen ca sd 189 cdy chdt ha dupe ddm vdng ndm dd xdc djnh tudi, lap md hinh udc tinh tudi cdy (A, ndm) theo cdp kinh va cap chidu cao d bang 4.

NONG NGHlfP VA PHAT TRI N N6NG TH6N-KY1 + 2 - THANG 2/2014 199

KHOA HQC C6WO NGH>

Bang 4: Md hinh udc tinh A theo DBH vi HStt Dang ham Ham R2 (90 P n Pbi CF AIC SX

1 A = f(DBH, H) sqrt(A_year) = -0,687835 + 0,231466*ln (DBH_cmA10/H_m) 69,139 0,000 189 0,000 1.48 -43.2 33,6*

Chia lam phan lam 3 cap sinh khoi TAGTB va 3 cap chteu cao H, tir dd co 9 to hop don vi lam phan dd du bao tang truong sinh khoi va hap thu C02 tung lam phdn. Tinh tang truong binh quan hang nam cua sinh khoi vi cic bon theo tung cip kinh thong qua mo hinh A, sau d6 tong hgp c6 dugc ting truong sinh khoi va hap thu C02 lam phin.

Tang truong sinh khoi va cac bon binh quan hang n3m dugc tinh theo cong thuc:

TTB

(7)ATTB =

ATTC = —A (8)

Trong d6:Ann. A-nx;: Tang truong binh quin sinh khdi

hoic cac bon (trfen va duoi mat dit cay gd), tan/ha/nam.

TTB, TTC: Tong sinh khoi hoac cac bon cua cay go trfen va dudi mat dat, tin/ha.

A Tudi theo cip kinh vi cap chidu cao cdy rung dugc tinh theo md hinh A - f(DBH, H) da lap.

Tinh toan cho 9 don vj voi 3 cap sinh khdi va 3 cip chidu cao, tong hgp dugc thong tin tang trudng sinh khdi, cic bon va hip thu C02 cua toan bd h£ thdng rung thudng xanh, vdi C02 - 3,67C d bang 5.

Bing 5: Tang trudng sinh khdi, cic bon vi hip thy C02 trfen cic don vj phan lo?i rung li rdng thudng xanh

Cip sinh khdi / TAGTB (tan/ha)

Chi tifeu tang trudng sinh khdi viC

CipHI II m

135 -155 (tin/ha)

Attr (tin/ha/nam) 4,98 4,32 3,63Arrc (tin/ha/nam) 2,30 1,99 1,67ATTC02 (tan/ha/nam) 8,46 7,32 6,13

2156-254 (tin/ha)

Attb (tan/ha/nam) 9,48 8,21 6,89A-rrc (tin/ha/nam) 4,40 3,80 3,18ATTC02 (tan/ha/nam) 16,15 13,95 11,68

3255-365 (tin/ha)

Attb (tin/ha/nam) 6,07 5,24 438Attc (tin/ha/nam) 2,83 2,44 2,04ATTc02 (tan/ha/nam) 10,40 8,97 7,49

■ TAGTB = 99 tin/ha ■ TAGTB = 222 tin/ha■ TAGTB = 331 tin/ha

III

Hinh 5: Hip thy C02 (tin/ha/nim) rung li rdng thudng xanh theo cip sinh khdi vi cip chidu cao

Kdt qua niy chi ra tang trudng thip nhit d cip sinh khdi 1 vi cip H III, vdi tang trudng sinh khdi li3,63 tin/ha/nim, cic bon li 1,67 tin/ha/nam vi hip thu C02 li 6,13 tin/ha/nim; ting trudng cao nhit d

cap sinh khdi 2 vi cip H I vdi sinh khdi li 9,84 tin/ha/nam, cic bon 4,40 tin/ha/nam vi hip thy C02 li 16,15 tin/ha/nam.

IPCC (2006) cho thiy tang trudng sinh khdi trfen mat dat rung mua nhidt ddi d chiu A bidn ddng 3,4-13,0 tin/ha/nam. Kdt qui nghifen cuu cua dd tii cung phu hgp vdi dd lidu qudc td, nhung ph$m vi bidn ddng hep hon vi cy thd cho rung nhidt ddi dTSy Nguyfen, Vidt Nam vi nhu viy chinh xic hon.

Hinh 5 vi bing 5 cho thiy khi ning hip thy C02 d cap chidu cao I li cao nhit d cic cip sinh khdi vi giam din ddn cip II vi DI, didu niy phu hyp vdi vide phin cip H, vi cip chidu cao I li chi thj cho cip ndng suit tdt nhit, sau dd giim din ddn cip II vi QL Trong khi dd hip thy C02 cao nhit d cip «nh khdi 2 (sinh khdi trung binh) d cic cip H, sau dd li cip 3 (sinh khdi cao nhit) vi thip nhit d d p «nh lrhAi 1

200 n 6 n g nghiEp vAphAt m i l n 6 n g ih 6 n -k ? i+ 2 -ih A n g 2/2014

KHOA HQC CONG NOHt

(sinh khdi thdp nhdt). Difeu nay cho thdy cdp sinh khdi 2 1 cdp c6 cdu true rung dn dinh nhung chua qua thdnh thuc do d6 nang lire hdp thu C02 la tot nhdt, trong khi d6 cdp sinh khoi 1 Id lam phdn rung bj tac dpng manh, suy giam khoi lupng va chdt lupng sinh khoi do vay lam giam khd nang hdp thu C02 cua rimg; rifeng cdp sinh khdi 3 la cdp co sinh khoi cao va gdn thanh thuc do vay tdc dp sinh trudng cua cay rimg da gidm va ldm giam kha nang hdp thu C02 cua loai lam phdn nay. Vfe ly thuydt lam hpc, sinh truong cua lam phdn se ngirr g khi dat thdnh thuc vd kha nang hdp thu C02 sfe bao hoa, tuy nhten loai lam phdn nay ndm ngoai pham vi nghten cuu.

4.KfrLUAN

- Dfe udc tinh, du bao sinh khoi, cac bon lam phdn cdn phan chia rimg thanh cac cdp chteu cao va cdc cap sinh khoi. Rimg ld rong thudng xanh Tay Nguyfen cdn phan chia thanh 3 cdp H va 3 cdp sinh khdi: Cdp 1: TAGTB * 99 tdn/ha, cdp 2: TAGTB * 222 tdn/ha, cdp 3: TAGTB = 331 tdn/ha.

- Sinh khdi vd cac bon lam phdn cdn dupe udc dnh thdng qua cdc md hinh phan bd N/DBH, tuong quan H/DBH va cac md hinh sinh trdc udc tinh sinh khdi, cac bon cua cay rimg trdn va dudi mat ddt Vifec udc tinh ndy cdn dupe tidn hdnh cho timg don vi phan loai theo cdp H vd cdp sinh khdi.

- Ddi vdi rimg ld rong thudng xanh vimg Tay Nguyfen lupng cdc bon tich luy thdp nhdt d cdp sinh khdi 1 vd cdp H III, vdi cdc bon trfen mat ddt ld 47,84 tdn/ha, dudi m$t ddt la 6,20 tdn/ha vd tong la 54,04 tdn/ha; lupng cdc bon tich luy cao nhdt d cdp sinh khdi 3 vd cdp H I, vdi cdc bon trfen mdt ddt ld 163,71 tdn/ha, dudi mdt dat ld 15,60 tdn/ha vd tdng ld 179,31 tdn/ha.

- TSng trudng sinh khdi, cdc bon vd hdp thu C02 cua ldm phdn trfen vd dudi mdt dat thdp nhdt d cdp sinh khdi 1 vd cdp H III, vdi tdng trudng sinh khdi ld3,63 tdn/ha/nam, cdc bon ld 1,67 tan/ha/nam vd hdp thy C02 ld 6,13 tdn/ha/nam; tang trudng cao nhdt d cdp sinh khdi 2 vd cdp H I vdi sinh khoi ld 9,84 tdn/ha/nam, cdc bon 4,40 tdn/ha/nam vd hdp thy C02 ld 16,15 tdn/ha/nam.

• Hdp thy C02 cua rung cao nhdt d cdp H 1 (tdt nhdt) vd dcdp sinh khdi 2 (cdp sinh khdi trung binh).

TAiu& inuaiiito

1. Bdo Huy, Nguyfen Thj Thanh Huong, Vd Hung, Cao Thi L& Nguyfen Due Dinh, 2012. Xay dyng md Hinh sinh trie dfe udc tinh sinh khdi vd cdc

bon cay rimg la rong thudng xanh vimg Tdy Nguyfen. Tap chi Rimg va Mdi trudng, sd 51(2012): 21 - 30.

2. Bao Huy, Cao Thi Ly. Vd Hung, Nguyfen Thj Thanh Huong, Nguyfen Due Dinh, 2012. Xdc djnh lupng C02 hap thu cua rimg ld rdng thudng xanh vimg Tay Nguyfen lam ca sd tham gia chuong trinh giam thteu khi phat thai tir suy thodi vd mdt rimg. Bao cao khoa hpc dfe tai khoa hpc cdng nghfe trpng difem cua Bd Giao due va Ddo t$o.

3. Bao Huy, 2013. Md hinh sinh trdc vd vifen thdm - GIS dfe xdc dinh lupng COz hdp thy cua rimg la rdng thudng xanh vimg Tay Nguyfen. Nxb Khoa hpc va Ky thuat

4. Basuki, T. M., Van Lake, P. E., Skidmore, A. K, Hussin, Y. A, 2009. Allometric equations for estimating the abobeground biomass in the tropical lowland Dipterocarp forests. Forest Ecology and Management 257(2009): 1684-1694.

5. Brown, S., 1997. Estimating biomass and biomass change of tropical forests: a Primer. FAO Forestry paper - 134. ISBN 92-5-103955-0. Available on web site: http://wwwiao.org/docrep/W4095E / w4095e00.htm#Contents.

6. Brown, S. 2002. Measuring cdc bon in forests: current status and future challenges. Environmental Pollution, 3(116): 363-372.

7. Brown, S. and Iverson, L R, 1992. Biomass estimates for tropical forests. World Resources Review 4:366-384.

8. Brown, S., Gillespie, A. J. R, and Lugo, A. E., 1989. Biomass estimation methods for tropical forests with applications to forest inventory data. Forest Science 35:881-902.

9. Chave, J., Andalo, C., Brown, S., Cairns, M. A., Chambers, J. Q., Eamus, D., Folster, H., Fromard, F., Higuchi, N., Kira, T., Lescure, J. P., Nelson, B. W., Ogawa, H., Puig, H., Riera, B., Yamakura, T., 2005. Tree allometry and improved estimatykm of carbon stocks and balance in tropical forests. Oecok>gial45 (2005): 87-99. DOI 10.1007/s0044240&0100x.

10. Dietz, J., Kuyah, S., 2011. Guidelines for establishing regional allometric equations for bimass estimation through destructive sampling World Agroforestry Center (ICRAF).

11. Henry, H., Benard, A., Asante, W. A., Eshun, J., Adu-Bredu, S., Valentini, R, Beraoux, M., Saint- Andre, L, 2010. Wood density, phytomass variations within and among trees, and allometric equations in

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s tropical rainforest of Africa. Forest Ecology and Management Journal, 260 (2010): 1375-1388.

12. Huy, B., Hung, V., Huong, N. T. T., Ly, C. T., Dinh, N. D., 2012. Tree allometric equations in Evergreen Broadleaf Forests in the South Central Coastal region, Viet Nam. In (Eds) Inoguchi, A, Henry, M. Birigazzi, L Sola, G., Tree allometric equation development for estimation of forest above­ground biomass in Viet Nam. UN-REDD Programme, Hanoi, Viet Nam.

13. ICRAF, 2007. Rapid carbon stock appraisal.14. IPCC, 2006. IPCC Guidelines for National

Greenhouse Gas Inventories. Prepared by the Natinal Greenhouse Gas Inventories Programme,

Eggleston H. S., Buendia L, Miwa K., Nsfara T., Tanabe K. (eds). Published: IGES, Japan.

15. Johannes, D., Shem, K., 2011, Guidelines for establishing reginonal allometric equations for biomass estimation through destructive sampling. CIFOR.

16. MacDicken, K. G., 1997. A Guide to Monitoring Cic bon Storage in Forestry and Agroforestry Projects. Winrock International Institute for Agricultural Development

17. Pearson, T., R., H., Brown, S., L, Birdsey, R, A, 2007. Measurement Guidelines for the Sequestration of Forest Cic bon. United States Department of Agriculture (USDA) Forest Service. General Technical Report NRS-18.

BIOMASS AND CARBON OF EVER GREEN BOARD-LEAF FORESTS IN THE CENTRAL HIGHLANDS,VIETNAM

Bao Huy1, Vo Hung, Nguyen Thi Thanh Huong, Cao Thi Ly, Nguyen Due Dinh, Pham Tuan Anh, Huynh Nhan Tri. Summary

On the basis of distribution of biomass, carbon per diameter classes in evergreen broadleaf forest in the Central Highlands, Vietnam for each unit classified as height (site index) and biomass levels, in which the forest is divided into three heigh index and biomass levels (level 1: 99 tons per ha, level 2: 222 tons per ha and level 3: 331 tons per ha) to determine the distribution of forest biomass and carbon; simultaneous application of tree allometric equations; the study has estimated for forest stand: the lowest above ground trees carbon is 47.84 tons/ha, below ground trees cac bon is 6.20 tons/ha and the total above and below ground trees carbon is 54.04 tons/ha; the highest above ground trees cic bon is 163.71 tons/ha, below ground trees cdc bon is 15.60 tons/ha and the total above and below ground trees cic bon is 179.31 tons/ha. Forest stand growth including above and below ground trees, the lowest trees biomass growth is 3.63 tons/ha/year, trees carbon is 1.67 tons/ha/year and C02 absorption is 6.13 tons/ha/year, the highest growth with above and below ground trees biomass is 9.84 tons/ha/year, 4.40 trees carbon tons/ ha/year and C02 absorption is 16.15 tons/ha/year.Key words: Allometric equation, biomass, carbon, Central Highlands, ever green broad leaf forestNgudi phin bi£n: PGS.TS. VO Dai HaiNgiy nh$n bii: 26/8/2013Ngiy thdng qua phin bi$n: 26/9/2013Ngiy duy£t ding: 03/10/2013

1 Tay Nguyen University

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