De tai "Nghien ctifu phuc hoi tUnq Id 6 tinh Khanh Hoa"
do Xi nghiep dieu tra thiet ke Lam Nong nghiep Khanh Hoa chu tri thi^c hien vdi muc ti^u nghien ciifu phuc hdi cua riifng lo 6 phat sinh, phat trien sau ni^dng ray, riifng lo 6 sau khai thac khong hdp ly tai 2 huyen Khanh Sdn va Khanh Vinh; de ra bien phap ky thuat cham soc, nuoi dirdng, khai thac hdp ly riifng lo 6; xay diinq quy trinh khai thac lo 0 phii hdp vdi dieu ki^n tii nhien, xa hoi miln niii Khanh Hoa.
Dl tai da liia chon va thiet lap cac khdi (block), d tidu chua'n (d miu - OTC) di nghidn ctifu tai 2 huyen Khanh Sdh va Khanh Vinh.
Ngoai ra, cdn suf dung phtidng phap sinh thai thiic nghiem, tao lap d mau, bo tri cac d miu theo kilu khdi day du ngiu nhidn ngoai thi/c dia.
KET QUA NGHIEN CUfU DE TAI:
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Xi nghi?p dieu tra thie't ke' Ldm Nong nghiep Khdnh Hda
KET QUA NGHIEN CQU CUA DE TAI
1. SU phat trien, phuc hoi rifng lo 6
Nghien cUu Id d d 3 md hinh; Id d phuc hdi sau nUPng rSy, Id d phuc hdi sau khai thac. Id d hdn giao vdi gd. Giai doan dau cua qua trinh phuc hdi Id d (nam 2005) diin ra rat nhanh va md hinh Id d phuc hdi sau nUPng rSy phuc hdi nhanh nhat (the hien d sd lupng mang ra cao nhat la 183 mang), nhung chat lupng rUng phuc hdi khdng cao (the hien
qua sinh khdi mang chi dat 0,35m^/
d/183 mang, tdc chi dat 0,0019m=/
mang so vdi 0,0056mVmang d hai md hinh kia). Sau mdt nam phuc hdi thi qua trinh phuc hdi cham hon, nhung chat lupng kha ddng deu d ca 3 md hinh (the hien qua sinh khdi mang lan lupt la: 0,0028;
0,0041 va 0,0034mVmang).
Ben canh dd, de tai tie'n hanh theo ddi do dem nhOng cay Id d trudng thanh. Sd lUpng Id d deu tang qua cac nam va chat lupng Id d nam sau cao hon nam trudc.
K H C N & J^TT K H A N H H O A • SO 4/2010
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Cu the: tren dien tich 1,3ha do dem thi nam 2005 cd 5.258 cay (tUPng dUPng 4.045 cay/ha), nam 2006 cd 15.011 cay (tUPng dUPng 11.547 cay/ha), nam 2007 cd 15.181 cay (tuPng duPng 11.677 cay/ha), nam 2008 cd 12.415 cay (tUPng dUPng 9.550 cay/ha), nam 2009 cd 13.453 cay (tUPng dUPng 10.348 cay/ha).
Qua qua trinh theo ddi va tham khao kinh nghiem cua ngudi dan dja phuong thi hien tupng Id d khuy thudng gSp d rUng Id d phuc hdi (khuy tu 10 - 20%/nam). Khi Id Id ra hoa vao khoang thang 1 - 2 thi cay Id d sinh trudng cham lai, cay chuyen tU mau xanh sang mau vang rdi chet trong khoang thang 6 - 7. Khi Id d khuy thi thudng khuy theo bui, day thuc chat la qua trinh sinh san nhim duy tri ndi gid'ng va md rdng nhanh qua trinh phan bd cua Id d bing each ra hoa va nhd gid dua hat Id d bay xa.
c) Ndi dung cac bien phap ky thuat:
- MUc dp tac ddng thap: giQ khdng de chan tha gia sue Idn; cd bien phap phdng chdng chay; bao ve chdng chSt pha Id d, khdng lay mang trong thdi gian phuc hdi; chi dupc tan dung cay khd, gia theo chi din cua can bd ky thuat.
- MUc dp tac ddng cao: phat dpn cay leo bui ram; cudc xdi da't theo rach xung quanh bui Id d de bdn thuc phan NPK khi cd mua tieu man xuat hien vdi lupng 100 - • 200kg/ha; tra dSm hat hoSc trdng bd sung Id d d cac khoang trdng Idn hon I.OOOm^.
- Van dung cac mUc dp tac ddng: can cU vao chUc nang cua rUng va dieu kien san xua't ma ap dung cac mUc dp tac ddng nhusau:
+ RUng phdng hd: chu ye'u tac ddng d mdc dp thap, trudng hpp dac biet d nhijfng nPi cd dieu kien
L6 d (ten khoa hpc la Bambusa procera A.Chev.et A.Cam) la loai cay rat phd bien d Khanh Hoa, co khoang 15.290 ha, chiem 8,41% di^n tich riifng toan tinh. L6 6 rS't gdn giii va quen thupc vdi ngt^di ddn, n6 gan liin vdi ddi sdng sinh hoat cua cac hp dong bao dan tpc hai huypn Khanh Sdn va Khanh Vinh. Thdi gian qua, vi^c khai thac lam dung vdn riKng, phat, ddt nifdng lam rSy da lam riifng id d suy kiet chuyin thanh riifng id d tep, nang suat thap, gia trj kinh t l kem.
2. Bl#n phap ky thuft cham soc, phuc hoi rifng lo 6
De tai SL/ dung bien phap ky thuat khoanh nudi phuc hdi rUng Id d, day la bien phap Ipi dung triet de quy luat tai sinh va diin the tU nhien vdi su can thiep hpp ly cua con ngudi.
a) Ddi tupng cu the xac djnh cho khoanh nudi, phuc hdi rUng:
dat da mat rUng, rdng Id d bj suy kiet; nUOng rSy bd hda nhung van cdn tfnh chat dat rdng, cd "tua rua"
Id d vdi dp che phu tren 20% dien tfch; dien tfch tdi thieu cho mot khu rUng khoanh nudi la 5ha (ddi vdi td chUc), 1 - 3ha (dd'i vdi hd gia dinh)
b) Thdi gian tac ddng: phu thudc tdng dd'i tupng va dieu kien lap dia, cd the keo dai td 4 - 6 nam.
cho phep mdi ap dung mdt sd bien phap d mdc dd tac ddng cao.
+ RUng dac dung: khu bao ve nghiem ngat ap dung cac bien phap d mUc dd tac ddng tha'p; khu phuc hdi sinh thai ap dung nhu khu bao ve nghiem ngat va cac bien phap d mUc dp tac ddng cao; vung dem ap dung cac bien phap d mUc dp tac ddng thap va cac bien phap lua chon cua mUc dp tac ddng cao;
rUng san xua't va phdng hd it xung yeu ap dung mdc dp tac ddng thap va cac bien phap lua chpn cua mUc dp tac ddng cao.
3. Mot so d^c diem lam hoc ciia riing lo 6 Khanh Hoa
a) Dac diem nhan biet: Ld d cd
2 phan rd ret la than ngam va than khf sinh; chung cd ca'u tao tuong dd'i gidng nhau, nhieu Idng, dd't va mat nhung do chUc nang, dieu kien sdng khac nhau din de'n cd nhOng khac biet rd ret.
- Than ngam: moc cum, dang cu trIng nga, dSc rudt, nhieu Idng ngin, phan each bdi cac dd't, dudng kinh than ngam bie'n ddng tU 2 - 7cm, binh quan 5cm, chieu dai 20-80cm.
- Than khi sinh: mang la giai doan non cua than khf sinh do than ngam nhd len khdi mSt da't tao thanh. Chieu cao cay 10 - 18cm, ngon cong ru, dudng kfnh than dao ddng rat Idn tuy thudc vao ngudn dinh dudng va ngudn nudc. Than luc non cd mau xanh bac, ve gia cd mau xanh dam va nhieu dja y tao nen nhOng ddm loang id, phien la thudn dai 20 - 30cm, rdng 1,5 - 2,5cm, be mo hinh thang can, phien mo hinh mui giao dai 20cm, rdng 4cm, ludi mo xe sau.
b) Phan bd, dSc diem sinh hpc va sinh thai hpc: Ld d phan bd d nPi cd khf hau nhiet ddi, chju anh hudng rd ret cua gid mua. Dja hinh mpc Id d la nhOng ddi tha'p, nhap nhd, lupn sdng, dat mau dd hoSc nau vang, thanh phan cP gidi thjt va da't set, Idp da't day tren 50cm.
Ld d ra hoa ke't hat d tUng khdm, hang nam moc tU thang 8 de'n thang 11. Dau vu mang mpc rai rac, tU thang 8 de'n thang 9 mang mpc manh nha't cd the dat tdi 3.000 mang/ha/thang. Thdi gian sinh trudng cua mang Id d khoang 70 ngay. Mang thudng chet d dp cao 30 - 50cm, tudi thp khdng qua 8 - 1 0 nam. Phan bd sd cay theo tudi d rUng gia la: tudi non 19%, tudi vUa 15%, tudi gia 66%.
c) Gia trj SLJ dung: Ld d cd khdi lupng the tfch khd kiet la 785kg/m^
dp ben nen dpc thd 598,7kg/m^ dp ben udn xuyen tam la 3.448kg/cm^
dp ben udn tie'p tuye'n 2.499kg/cm^
dap Ung nhu cau trong xay dung.
Than Id d cd ty le xenlulo tren 50%, lignin 22,3%, chieu dai spi 1,9 -
KHCN & MT K H A N H HOA • SO 4/2010
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NIEM T U H A O
J\[jdn ndm Non nUdc co Thdng Long Con chdu xitng danh gidng Lac Hong Giif nudc bao ddi to sdc thdm
Que huang ngdi sdng toa menh mong.
San xuat...
(Tiep theo trang 4) cao sUc canh tranh cua cdng nghiep che bie'n rong bien tai Viet Nam.
- Gdp phan chuyen djch cd ca'u kinh te - xa hdi va thuc day phat trie'n khoa hpc - cdng nghe.
Duoc bie't, hien nay Vien nghien cUu va Ung dung cdng nghe Nha Trang dang trien khai du an san xua't fhiT nghiem KC02/06-10:
"Hoan thien quy trinh cdng nghe san xua't Fucoidan va cdng nghe alginat tU ba thai rong Nau" do TS. Tran Thj Thanh Van lam Chij nhiem dU an va da dUOc tuye'n chpn thUc hien de tai: "Nghien cUu qui trinh cdng nghe tao nguyen lieu ho trp dieu trj benh ung thU"
thudc ChUPng trinh nghien cUu khoa hpc cdng nghe trpng diem qud'c gia phat trie'n cdng nghiep hda dUdc de'n nam 2020, thUc hien vao nam 2011 - 2013 do TS. Nguyin Duy NhUt lam Chij nhiem de fai.H
2,2mm nen la nguyen lieu tdt cho san xua't giay trIng cao cap. Cay cd Idng dai thfch hpp che bie'n van ep. Trong cudc sdng hang ngay. Id d dap Ung nhu cau sinh hoat tU viec lam dd dung de'n mang an.
d) Thin vong: Ld d la cay rUng tu nhien cd kha nang phuc hdi sau khi bj tac ddng ne'u dupc quan ly va bao ve td't. Ve nguyen tie, cd the chat tU cay tudi 3 va phUPng thUc chung la chat chpn tUng cay theo cap tudi.
4. Moi quan he gluTa cUdng do khai thac chpn lo 6 vdi siT tai sinh va sinh trUdng ciia mang. De xuat bien phap khai thac hpp iy, chu ky khai thac rifng id 6 tai Khanh Hoa
De tai nghien cUu 3 nghiem thUc (NT) d 3 cudng dp khai thac chpn khac nhau (NTA: chat 100%
cay tudi 4 trd len, NTB: chat nhu NTA va chat them 50% cay tudi 3, NTC: chat 100% cay tudi 3 trd len) va 1 nghiem thUc dd'i chUng NTD:
khdng chat. Qua dd, cho tha'y cac
chi tieu sinh trudng mang d cac nghiem thUc khai thac chpn deu tha'p hPn nghiem thUc ddi chUng.
Nam dau tien (2006) tien hanh khai thac tren tat ca cac d khai thac (OKT) d 3 chu ky (1 nam, 2 nam, 3 nam), den nam thU hai (2007) tie'n hanh khai thac tren OKT d chu ky 1 nam thi nhan tha'y chi tieu sinh trudng ve dudng kfnh mang d nhOng OKT chu ky 1 nam deu thap hon cac chi tieu sinh trudng mang d nhOng OKT cdn lai. Nam 2008 tien hanh khai thac tren OKT d chu ky 1 nam, 2 nam nhan thay chi tieu sinh trudng ve dudng kfnh mang d nhOng OKT chu ky 1 nam la thap nhat (3,3cm), cao nhat la chu ky 3 nam (4,5cm). Chi tieu sinh trudng chieu cao mang tha'p nha't d OKT chu ky 3 nam (8,0m), cao nhat d OKT chu ky 2 nam (8,9m).
Chi tieu sd lupng mang thap nha't d OKT chu ky 2 nam, cao nhat d OKT chu ky 3 nam. Chi tieu ve sinh khdi mang cao nhat d OKT chu ky 3 nam (0,1022m3), thap nhat d OKT
chu ky 1 nam (0,0555m^).
Khi tien hanh khai thac vdi cUdng dd trung binh 50% cay tuoi 3 va 100% cay tudi 4 trd len va ket hpp chu ky khai thac 3 nam se cho hieu qua cao nha't. NhUng ne'u xet ve tfnh hieu qua kinh te va xa hdi thi ap dung bien phap khai thac vdi cudng dp trung binh ke't hpp chu ky khai thac 1 nam la hpp ly nha't.
DE XUAT, KIEN NGHj 1. Can quan ly chat che, khai thac hpp ly d l dam bao tai sinh rUng, dap Ung nhu cau sd dung Id d mdt each lau dai.
2. Can cd quy hoach vung phat trien Id d, khoanh nudi cham sdc cac rUng thU sinh cd Id d de tang them dien tfch, trO lupng va chat lupng rUng.
3. Khi tien hanh nhan rdng md hinh thi nen cd su tham gia cua ngudi dan theo kieu lam nghiep cdng ddng se giup cho ngudi dan vUa cd thu nhap vUa bao ve rUng Id d td't hOn.B
KHCN & N T KHANH HOA • SO 4/2010
