{"id":8948,"date":"2007-05-16T03:17:20","date_gmt":"2007-05-15T20:17:20","guid":{"rendered":"http:\/\/vafs.gov.vn\/vn\/2007\/05\/nghich-ly-cay-ban-dia\/"},"modified":"2013-10-06T09:00:55","modified_gmt":"2013-10-06T02:00:55","slug":"nghich-ly-cay-ban-dia","status":"publish","type":"post","link":"https:\/\/vafs.gov.vn\/vn\/nghich-ly-cay-ban-dia\/","title":{"rendered":"Ngh\u1ecbch l\u00fd c\u00e2y b\u1ea3n \u0111\u1ecba"},"content":{"rendered":"<p>Nguy\u1ec5n Ho\u00e0ng Ngh\u0129aVi\u1ec7n Khoa h\u1ecdc L\u00e2m nghi\u1ec7p VN<strong>M\u1edf \u0111\u1ea7u<\/strong>R\u1eebng t\u1ef1 nhi\u00ean c\u1ee7a c\u00e1c n\u01b0\u1edbc nhi\u1ec7t \u0111\u1edbi c\u00f3 m\u1ee9c \u0111\u1ed9 \u0111a d\u1ea1ng cao v\u1ec1 c\u00e1c lo\u00e0i th\u1ef1c v\u1eadt. Theo nh\u00e0 khoa h\u1ecdc van Steenis (1971) th\u00ec v\u00f9ng \u0110\u00f4ng Nam \u00e1 bao g\u1ed3m c\u1ea3 Vi\u1ec7t Nam, c\u00f3 t\u1edbi 25 000 lo\u00e0i th\u1ef1c v\u1eadt c\u00f3 hoa, chi\u1ebfm 10% t\u1ed5ng s\u1ed1 lo\u00e0i th\u1ef1c v\u1eadt c\u00f3 hoa c\u1ee7a th\u1ebf gi\u1edbi, trong \u0111\u00f3 c\u00f3 t\u1edbi 40% s\u1ed1 lo\u00e0i l\u00e0 lo\u00e0i \u0111\u1eb7c h\u1eefu, ngh\u0129a l\u00e0 ch\u1ec9 g\u1eb7p \u1edf ri\u00eang v\u00f9ng n\u00e0y m\u00e0 th\u00f4i.H\u1ec7 th\u1ef1c v\u1eadt r\u1eebng Vi\u1ec7t Nam c\u0169ng c\u00f3 ti\u1ebfng l\u00e0 phong ph\u00fa v\u00e0 \u0111a d\u1ea1ng. Theo Vi\u1ec7n Sinh th\u00e1i v\u00e0 t\u00e0i nguy\u00ean sinh v\u1eadt (1993), ch\u1ec9 ri\u00eang ng\u00e0nh Khuy\u1ebft th\u1ef1c v\u1eadt (<em>Ptesidophyta<\/em>), ng\u00e0nh H\u1ea1t tr\u1ea7n (<em>Gymnospermae<\/em>) v\u00e0 ng\u00e0nh H\u1ea1t k\u00edn (<em>Angiospermae<\/em>) \u0111\u00e3 c\u00f3 kho\u1ea3ng 11000 lo\u00e0i c\u1ee7a tr\u00ean 2500 chi, trong \u0111\u00f3 c\u00f3 kho\u1ea3ng 7 000 lo\u00e0i th\u1ef1c v\u1eadt b\u1eadc cao c\u00f3 m\u1ea1ch.Do nhi\u1ec1u nguy\u00ean nh\u00e2n kh\u00e1c nhau m\u00e0 trong giai \u0111o\u1ea1n v\u1eeba qua, di\u1ec7n t\u00edch r\u1eebng c\u1ee7a n\u01b0\u1edbc ta \u0111\u00e3 gi\u1ea3m \u0111\u00e1ng k\u1ec3, v\u1edbi t\u1ed1c \u0111\u1ed9 kho\u1ea3ng tr\u00ean d\u01b0\u1edbi 100 000 ha\/n\u0103m. T\u1ef7 l\u1ec7 che ph\u1ee7 c\u1ee7a r\u1eebng gi\u1ea3m t\u1eeb 40,7% (13,5 tri\u1ec7u ha r\u1eebng) v\u00e0o n\u0103m 1943 (Maurand, 1943) xu\u1ed1ng c\u00f2n 27,1% v\u00e0o n\u0103m 1980 v\u00e0 26,2% v\u00e0o n\u0103m 1985 (B\u1ed9 L\u00e2m nghi\u1ec7p, 1991). Nhi\u1ec1u t\u1ec9nh quan tr\u1ecdng \u1edf mi\u1ec1n n\u00fai ph\u00eda B\u1eafc nh\u01b0 S\u01a1n La, Lai Ch\u00e2u, Cao B\u1eb1ng v.v. c\u00f3 t\u1ef7 l\u1ec7 che ph\u1ee7 c\u1ee7a r\u1eebng r\u1ea5t th\u1ea5p, ch\u1ec9 c\u00f2n tr\u00ean d\u01b0\u1edbi 10%. Vi\u1ec7c ph\u1ee5c h\u1ed3i, t\u00e1i sinh r\u1eebng \u0111ang l\u00e0 m\u1ed9t nhu c\u1ea7u b\u1ee9c b\u00e1ch, nh\u1ea5t l\u00e0 cho nh\u1eefng khu v\u1ef1c ph\u00f2ng h\u1ed9 \u0111\u1ea7u ngu\u1ed3n, ven bi\u1ec3n v\u00e0 \u0111\u1ec3 \u0111\u00e1p \u1ee9ng nhu c\u1ea7u ti\u00eau d\u00f9ng c\u1ee7a x\u00e3 h\u1ed9i, k\u1ec3 c\u1ea3 cho xu\u1ea5t kh\u1ea9u. Vai tr\u00f2 c\u1ee7a c\u00e1c lo\u00e0i c\u00e2y b\u1ea3n \u0111\u1ecba trong c\u00f4ng t\u00e1c tr\u1ed3ng r\u1eebng l\u00e0 r\u1ea5t r\u00f5 r\u00e0ng, song hi\u1ec7n t\u1ed3n t\u1ea1i v\u00f4 s\u1ed1 ngh\u1ecbch l\u00fd \u1edf t\u1ea7m qu\u1ed1c t\u1ebf v\u00e0 \u1edf m\u1ed7i qu\u1ed1c gia, \u0111\u00f2i h\u1ecfi c\u00e1c nh\u00e0 nghi\u00ean c\u1ee9u v\u00e0 qu\u1ea3n l\u00fd s\u1edbm quan t\u00e2m, gi\u1ea3i quy\u1ebft.c\u00e1c ngh\u1ecbch l\u00fd c\u01a1 b\u1ea3n.<strong>1. Ngh\u1ecbch l\u00fd th\u1ee9 nh\u1ea5t : Th\u1ebf gi\u1edbi \u01b0a c\u1ee7a ngo\u1ea1i. <\/strong>Ngh\u1ecbch l\u00fd n\u00e0y c\u00f3 t\u1ea7m qu\u1ed1c t\u1ebf v\u00e0 \u0111i\u1ec1u d\u1ec5 nh\u1eadn bi\u1ebft nh\u1ea5t \u0111\u00f3 l\u00e0 vi\u1ec7c s\u1eed d\u1ee5ng r\u1ed9ng r\u00e3i c\u00e1c lo\u00e0i c\u00e2y n\u00f4ng nghi\u1ec7p tr\u00ean ph\u1ea1m vi to\u00e0n c\u1ea7u. Th\u00f4ng th\u01b0\u01a1ng qu\u1ed1c t\u1ebf v\u00e0 khu v\u1ef1c t\u1eeb h\u00e0ng tr\u0103m, h\u00e0ng ngh\u00ecn n\u0103m qua \u0111\u00e3 g\u00f3p ph\u1ea7n trao \u0111\u1ed5i c\u00e1c gi\u1ed1ng c\u00e2y tr\u1ed3ng quan tr\u1ecdng gi\u1eefa c\u00e1c v\u00f9ng v\u00e0 c\u00e1c l\u1ee5c \u0111\u1ecba kh\u00e1c nhau. Kh\u00f4ng c\u00f3 n\u01b0\u1edbc n\u00e0o c\u00f3 th\u1ec3 t\u1ef1 cung c\u1ea5p n\u1ed5i ngu\u1ed3n t\u00e0i nguy\u00ean ditruy\u1ec1n cho ri\u00eang m\u00ecnh cho d\u00f9 n\u01b0\u1edbc \u0111\u00f3 c\u00f3 gi\u00e0u c\u00f3 \u0111\u1ebfn m\u1ee9c n\u00e0o \u0111i n\u1eefa v\u1ec1 m\u1eb7t t\u00e0i nguy\u00ean. C\u00e1c lo\u00e0i c\u00e2y c\u00f3 ngu\u1ed3n g\u1ed1c t\u1eeb ch\u00e2u \u00e1 nh\u01b0 l\u00faa n\u01b0\u1edbc (<em>Oryza sativa<\/em>), c\u00e1c lo\u00e0i chu\u1ed1i (<em>Musa<\/em> spp.), d\u1eeba (<em>Cocos nucifera<\/em>) kh\u00f4ng ch\u1ec9 quan tr\u1ecdng \u1edf v\u00f9ng ch\u00e2u \u00e1, m\u00e0 c\u00f2n c\u00f3 vai tr\u00f2 kinh t\u1ebf v\u00e0 dinh d\u01b0\u1ee1ng l\u1edbn lao \u1edf ch\u00e2u Phi v\u00e0 ch\u00e2u M\u1ef9. Hoa k\u1ef3 \u1edf ch\u00e2u M\u1ef9 l\u00e0 m\u1ed9t trong ba n\u01b0\u1edbc xu\u1ea5t kh\u1ea9u g\u1ea1o l\u1edbn nh\u1ea5t th\u1ebf gi\u1edbi c\u00f9ng v\u1edbi Th\u00e1i Lan v\u00e0 Vi\u1ec7t Nam \u1edf ch\u00e2u \u00e1. \u0110\u1eadu t\u01b0\u01a1ng (<em>Glycine soja<\/em>) c\u00f3 ngu\u1ed3n g\u1ed1c t\u1eeb ph\u00eda b\u1eafc Trung Qu\u1ed1c nay \u0111\u01b0\u1ee3c tr\u1ed3ng r\u1ed9ng r\u00e3i \u1edf ch\u00e2u M\u1ef9 v\u00e0 v\u00f9ng n\u00e0y \u0111\u00e3 t\u1eebng \u0111\u1ea1t t\u1edbi 74% m\u1ee9c s\u1ea3n xu\u1ea5t c\u1ee7a th\u1ebf gi\u1edbi. Theo Th\u1eddi b\u00e1o Kinh t\u1ebf Vi\u1ec7t Nam(1997), n\u0103m n\u01b0\u1edbc ch\u00e2u M\u1ef9 l\u00e0 Hoa K\u1ef3, Braxin, \u00e1chentina, Cana\u0111a v\u00e0 Paragoay \u0111\u00e3 \u0111\u1ea1t 80,6% s\u1ea3n l\u01b0\u1ee3ng \u0111\u1eadu t\u01b0\u01a1ng th\u1ebf gi\u1edbi v\u1ee5 \u0111\u1eadu t\u01b0\u01a1ng n\u0103m 1995\/1996 v\u00e0 \u01b0\u1edbc \u0111\u1ea1t kho\u1ea3ng 82,3% v\u00e0o v\u1ee5 96\/97. Ng\u01b0\u1ee3c l\u1ea1i khoai lang (<em>Ipomoea batatas<\/em>) c\u00f3 ngu\u1ed3n g\u1ed1c \u1edf Nam M\u1ef9 th\u00ec nay c\u00f3 t\u1edbi 90% t\u1ed5ng s\u1ea3n l\u01b0\u1ee3ng khoai lang tr\u00ean th\u1ebf gi\u1edbi l\u1ea1i b\u1eaft ngu\u1ed3n t\u1eeb ch\u00e2u \u00e1 bao g\u1ed3m Trung Qu\u1ed1c, Vi\u1ec7t Nam v\u00e0 Papua New Guinea. C\u0169ng nh\u01b0 v\u1eady, ng\u00f4 (<em>Zea mays<\/em>) c\u00f3 ngu\u1ed3n g\u1ed1c t\u1eeb Trung v\u00e0 Nam M\u1ef9 nay \u0111\u01b0\u1ee3c g\u00e2y tr\u1ed3ng tr\u00ean ph\u1ea1m vi to\u00e0n th\u1ebf gi\u1edbi. \u0110i\u1ec1u \u0111\u00e1ng \u0111\u01b0\u1ee3c nh\u1ea5n m\u1ea1nh \u1edf \u0111\u00e2y l\u00e0 tr\u00ean ph\u1ea1m vi to\u00e0n c\u1ea7u, ba lo\u00e0i c\u00e2y tr\u1ed3ng quan tr\u1ecdng nh\u1ea5t l\u00e0 ng\u00f4, l\u00faa n\u01b0\u1edbc v\u00e0 l\u00faa m\u00ec cung c\u1ea5p kho\u1ea3ng 60% l\u01b0\u1ee3ng calori v\u00e0 protein m\u00e0 con ng\u01b0\u1eddi l\u1ea5y \u0111\u01b0\u1ee3c t\u1eeb th\u1ef1c v\u1eadt. C\u00f2n v\u00f4 s\u1ed1 c\u00e1c lo\u00e0i c\u00e2y tr\u1ed3ng kh\u00e1c c\u00f3 ngu\u1ed3n g\u1ed1c ngo\u1ea1i lai m\u00e0 hi\u1ec7n nay nh\u00e2n lo\u1ea1i v\u1eabn \u0111ang s\u1eed d\u1ee5ng r\u1ea5t th\u00e0nh c\u00f4ng v\u00e0 mang l\u1ea1i hi\u1ec7u qu\u1ea3 kinh t\u1ebf l\u1edbn nh\u01b0 c\u00e2y \u0111i\u1ec1u (<em>Anacardium occidentale<\/em>), cao su (<em>Hevea brasiliensis<\/em>), c\u00e0 ph\u00ea v.v.<strong>2. Ngh\u1ecbch l\u00fd th\u1ee9 hai : L\u00e2m nghi\u1ec7p th\u1ebf gi\u1edbi th\u00edch tr\u1ed3ng c\u00e2y nh\u1eadp n\u1ed9i.<\/strong>B\u1ea1ch \u0111\u00e0n (<em>Eucalyptus<\/em> L\u2019Herit) l\u00e0 chi th\u1ef1c v\u1eadt thu\u1ed9c h\u1ecd Sim (<em>Myrtaceae<\/em>) v\u1edbi tr\u00ean 500 lo\u00e0i ch\u1ec9 c\u00f3 ph\u00e2n b\u1ed1 duy nh\u1ea5t \u1edf \u00d4xtr\u00e2ylia (tr\u1eeb hai lo\u00e0i l\u00e0 <em>E.urophylla<\/em> g\u1eb7p \u1edf In\u0111\u00f4n\u00eaxia v\u00e0 <em>E.deglupta <\/em>g\u1eb7p \u1edf Philipin). Theo \u01b0\u1edbc t\u00ednh c\u1ee7a T\u1ed5 ch\u1ee9c L\u01b0\u01a1ng n\u00f4ng (FAO) th\u00ec cho t\u1edbi n\u0103m 1985, \u0111\u00e3 c\u00f3 g\u1ea7n tr\u0103m n\u01b0\u1edbc g\u00e2y tr\u1ed3ng b\u1ea1ch \u0111\u00e0n trong \u0111\u00f3 di\u1ec7n t\u00edch r\u1eebng tr\u1ed3ng \u1edf 13 n\u01b0\u1edbc tr\u1ed3ng nhi\u1ec1u nh\u1ea5t \u0111\u00e3 \u0111\u1ea1t tr\u00ean 5 tri\u1ec7u ha v\u00e0 60 n\u01b0\u1edbc c\u00f2n l\u1ea1i tr\u1ed3ng \u0111\u01b0\u1ee3c n\u1eeda tri\u1ec7u ha. C\u00e1c n\u01b0\u1edbc tr\u1ed3ng nhi\u1ec1u nh\u1ea5t l\u00fac \u0111\u00f3 l\u00e0 :\u00b7Braxin, ch\u00e2u M\u1ef9: 2.500.000 ha\u00b7\u1ea5n \u0110\u1ed9, ch\u00e2u \u00e1:550.000\u00b7Nam Phi, ch\u00e2u Phi:470.000\u00b7B\u1ed3 \u0110\u00e0o Nha, ch\u00e2u \u00c2u:430.000\u00b7\u0102ng\u00f4la, ch\u00e2u Phi:390.000\u00b7T\u00e2y Ban Nha, ch\u00e2u \u00c2u:390.000\u00b7Trung Qu\u1ed1c, ch\u00e2u \u00e1:300.000\u00b7\u00cati\u00f4pi, ch\u00e2u Phi:250.000\u00b7\u00e1chentina, ch\u00e2u M\u1ef9:240.000\u00b7Ma-r\u1ed1c, ch\u00e2u Phi:180.000\u0110i\u1ec1u ngh\u1ecbch l\u00fd l\u00e0 cho t\u1edbi n\u0103m 1989, c\u1ea3 \u0111\u1ea5t n\u01b0\u1edbc \u00d4xtr\u00e2ylia r\u1ed9ng l\u1edbn, x\u1ee9 s\u1edf c\u1ee7a b\u1ea1ch \u0111\u00e0n l\u1ea1i m\u1edbi ch\u1ec9 tr\u1ed3ng \u0111\u01b0\u1ee3c 55.000 ha, ngh\u0129a l\u00e0 b\u1eb1ng g\u1ea7n 1% c\u1ee7a to\u00e0n th\u1ebf gi\u1edbi v\u00e0 ch\u1ec9 b\u1eb1ng 1\/5 c\u1ee7a Braxin n\u0103m 1985. \u01af\u1edbc t\u00ednh cho t\u1edbi n\u0103m 2000, to\u00e0n th\u1ebf gi\u1edbi tr\u1ed3ng \u0111\u01b0\u1ee3c kho\u1ea3ng 10 tri\u1ec7u ha b\u1ea1ch \u0111\u00e0n.\u0110i\u1ec1u ngh\u1ecbch l\u00fd n\u00e0y c\u0169ng l\u1ea1i \u0111\u00fang cho c\u00e1c lo\u00e0i keo <em>Acacia<\/em>. Keo <em>Acacia<\/em> l\u00e0 chi th\u1ef1c v\u1eadt thu\u1ed9c h\u1ecd \u0110\u1eadu (<em>Leguminosae<\/em>) g\u1ed3m kho\u1ea3ng 1200 lo\u00e0i, trong \u0111\u00f3 ri\u00eang \u00d4xtr\u00e2ylia c\u0169ng \u0111\u00e3 c\u00f3 t\u1edbi 850 lo\u00e0i. L\u1ea1i m\u1ed9t l\u1ea7n n\u1eefa c\u00e1c n\u01b0\u1edbc ch\u00e2u \u00e1 l\u00e0 n\u01a1i g\u00e2y tr\u1ed3ng nhi\u1ec1u nh\u1ea5t c\u00e1c lo\u00e0i Keo \u00d4xtr\u00e2ylia. \u0110\u1ebfn n\u0103m 1991, Trung qu\u1ed1c \u0111\u00e3 tr\u1ed3ng 60.000 ha, ri\u00eang \u0111\u1ea3o Xumat\u01a1ra c\u1ee7a In\u0111\u00f4n\u00eaxia \u0111\u00e3 tr\u1ed3ng 38.000 ha t\u1edbi n\u0103m 1990. Malaixia \u0111\u00e3 c\u00f3 61.000 ha keo tai t\u01b0\u1ee3ng (<em>A.mangium<\/em>) v\u00e0o n\u0103m 1991 v\u00e0 d\u1ef1 ki\u1ebfn \u0111\u1ea1t n\u1eeda tri\u1ec7u ha t\u1edbi n\u0103m 2000.Trong khi th\u1edd \u01a1 v\u1edbi vi\u1ec7c tr\u1ed3ng b\u1ea1ch \u0111\u00e0n v\u00e0 keo <em>Acacia<\/em> b\u1ea3n \u0111\u1ecba, \u00d4xtr\u00e2ylia l\u1ea1i h\u0103ng h\u00e1i tr\u1ed3ng c\u00e1c lo\u00e0i c\u00e2y nh\u1eadp n\u1ed9i cho n\u0103ng su\u1ea5t cao \u0111\u00f3 l\u00e0 th\u00f4ng carib\u00ea (<em>Pinus caribaea<\/em>), th\u00f4ng elliottii (<em>P.elliottii<\/em>) c\u00f3 ngu\u1ed3n g\u1ed1c t\u1eeb ch\u00e2u M\u1ef9 v\u00e0 c\u00e2y lai c\u1ee7a hai lo\u00e0i tr\u00ean. Ri\u00eang bang Queensland, trong t\u1ed5ng s\u1ed1 176.000 ha r\u1eebng tr\u1ed3ng, c\u00f3 40% l\u00e0 th\u00f4ng elliottii, 35% l\u00e0 th\u00f4ng carib\u00ea v\u00e0 ch\u1ec9 c\u00f3 25% l\u00e0 c\u1ee7a c\u00e2y b\u1ea3n \u0111\u1ecba. New Zealand l\u00e0 \u0111\u1ea5t n\u01b0\u1edbc n\u1ed5i ti\u1ebfng th\u1ebf gi\u1edbi v\u1ec1 tr\u1ed3ng r\u1eebng th\u00f4ng radiata (<em>Pinus radiata<\/em>) c\u00f3 n\u0103ng su\u1ea5t cao v\u00e0 \u0111\u00e2y l\u00e0 c\u00e2y tr\u1ed3ng r\u1eebng ch\u1ee7 y\u1ebfu c\u1ee7a \u0111\u1ea5t n\u01b0\u1edbc n\u00e0y. Song kh\u00f3 ai tin \u0111\u01b0\u1ee3c r\u1eb1ng, th\u00f4ng radiata l\u00e0 c\u00e2y nh\u1eadp n\u1ed9i c\u00f3 ngu\u1ed3n g\u1ed1c t\u1eeb b\u1eafc M\u1ef9 l\u1ea1i c\u00f3 t\u1ea7m quan tr\u1ecdng kh\u00f3 l\u01b0\u1eddng \u1edf ngo\u00e0i v\u00f9ng ph\u00e2n b\u1ed1 c\u1ee7a n\u00f3.<strong><\/strong><strong>3. Ngh\u1ecbch l\u00fd th\u1ee9 ba : Vi\u1ec7t <\/strong><strong>Nam<\/strong><strong> tr\u1ed3ng th\u00e0nh c\u00f4ng nhi\u1ec1u c\u00e2y nh\u1eadp n\u1ed9i<\/strong>.Vi\u1ec7t Nam c\u00f3 nhi\u1ec1u lo\u00e0i c\u00e2y nh\u1eadp n\u1ed9i \u0111\u00e3 \u0111\u01b0\u1ee3c g\u00e2y tr\u1ed3ng th\u00e0nh c\u00f4ng tr\u00ean di\u1ec7n r\u1ed9ng. N\u1ebfu ch\u1ec9 k\u1ec3 \u0111\u1ebfn c\u00e1c lo\u00e0i c\u00e2y g\u1ed7, c\u00e2y \u0111\u1eb7c s\u1ea3n th\u00ec \u0111\u00f3 l\u00e0 c\u00e2y \u0111i\u1ec1u, c\u00e2y cao su, c\u00e0 ph\u00ea, long n\u00e3o, x\u00e0 c\u1eeb, sa mu, phi lao, th\u00f4ng \u0111u\u00f4i ng\u1ef1a, th\u00f4ng carib\u00ea, t\u1ebfch, b\u1ea1ch \u0111\u00e0n, keo v.v. Nhi\u1ec1u lo\u00e0i c\u00e2y trong s\u1ed1 \u0111\u00f3 \u0111\u00e3 tr\u1edf th\u00e0nh quen thu\u1ed9c v\u00e0 kh\u00f4ng th\u1ec3 thi\u1ebfu trong \u0111\u1eddi s\u1ed1ng c\u1ee7a nh\u00e2n d\u00e2n ta. \u0110\u1ed1i v\u1edbi v\u00f9ng c\u00e1t ven bi\u1ec3n, phi lao \u0111\u00e3 tr\u1edf n\u00ean kh\u00f4ng th\u1ec3 thay th\u1ebf; th\u00f4ng \u0111u\u00f4i ng\u1ef1a v\u00e0 sa mu \u0111\u00e3 \u0111\u01b0\u1ee3c coi nh\u01b0 c\u00e2y b\u1ea3n \u0111\u1ecba c\u1ee7a v\u00f9ng n\u00fai ph\u00eda B\u1eafc.Vi\u1ec7n Khoa h\u1ecdc L\u00e2m nghi\u1ec7p Vi\u1ec7t Nam \u0111\u00e3 \u0111\u1ec1 xu\u1ea5t 92 lo\u00e0i c\u00e2y cho tr\u1ed3ng r\u1eebng \u1edf c\u00e1c v\u00f9ng sinh th\u00e1i kh\u00e1c nhau trong c\u1ea3 n\u01b0\u1edbc, trong \u0111\u00f3 c\u00f3 20 lo\u00e0i nh\u1eadp n\u1ed9i v\u00e0 tr\u00ean 70 lo\u00e0i b\u1ea3n \u0111\u1ecba, song c\u00e2y nh\u1eadp n\u1ed9i v\u1eabn chi\u1ebfm t\u1ef7 tr\u1ecdng g\u00e2y tr\u1ed3ng l\u1edbn. Theo Nguy\u1ec5n Ng\u1ecdc Lung (1994), trong t\u1ed5ng s\u1ed1 23 lo\u00e0i c\u00e2y ph\u1ee5c v\u1ee5 tr\u1ed3ng r\u1eebng \u1edf mi\u1ec1n B\u1eafc Vi\u1ec7t nam, ch\u1ec9 ri\u00eang 5 lo\u00e0i ho\u1eb7c nh\u00f3m lo\u00e0i c\u00e2y nh\u1eadp n\u1ed9i l\u00e0 nh\u00f3m lo\u00e0i b\u1ea1ch \u0111\u00e0n, keo tai t\u01b0\u1ee3ng, keo l\u00e1 tr\u00e0m, phi lao v\u00e0 th\u00f4ng \u0111u\u00f4i ng\u1ef1a \u0111\u00e3 chi\u1ebfm t\u1edbi 54% t\u1ed5ng s\u1ed1 di\u1ec7n t\u00edch r\u1eebng tr\u1ed3ng. V\u1ee5 Khoa h\u1ecdc C\u00f4ng ngh\u1ec7, B\u1ed9 L\u00e2m nghi\u1ec7p (1994) cho bi\u1ebft trong giai \u0111o\u1ea1n 1986-1992, di\u1ec7n t\u00edch r\u1eebng tr\u1ed3ng 10 lo\u00e0i c\u00e2y nh\u1eadp n\u1ed9i l\u00e0 th\u00f4ng \u0111u\u00f4i ng\u1ef1a, th\u00f4ng carib\u00ea, b\u1ea1ch \u0111\u00e0n caman, b\u1ea1ch \u0111\u00e0n t\u00ear\u00ea, b\u1ea1ch \u0111\u00e0n ur\u00f4 v\u00e0 b\u1ea1ch \u0111\u00e0n li\u1ec5u, keo tai t\u01b0\u1ee3ng , keo l\u00e1 tr\u00e0m, \u0111i\u1ec1u, t\u1ebfch \u0111\u00e3 chi\u1ebfm t\u1edbi 61% t\u1ed5ng di\u1ec7n t\u00edch r\u1eebng tr\u1ed3ng, c\u00f2n 11 lo\u00e0i c\u00e2y b\u1ea3n \u0111\u1ecba ch\u00ednh ch\u1ec9 chi\u1ebfm 39%.\u0110i\u1ec1u c\u00f3 ngu\u1ed3n g\u1ed1c t\u1eeb Nam M\u1ef9 (Braxin) song \u0111\u00e3 \u0111\u01b0\u1ee3c nh\u1eadp v\u00e0o \u1ea5n \u0110\u1ed9 t\u1eeb h\u01a1n 400 n\u0103m v\u00e0 v\u00e0o Vi\u1ec7t Nam t\u1eeb h\u01a1n 200 n\u0103m. N\u01b0\u1edbc ta hi\u1ec7n nay l\u00e0 m\u1ed9t trong 4 n\u01b0\u1edbc c\u00f3 di\u1ec7n t\u00edch tr\u1ed3ng v\u00e0 s\u1ea3n l\u01b0\u1ee3ng h\u1ea1t \u0111i\u1ec1u cao nh\u1ea5t \u0111\u00f3 l\u00e0 \u1ea5n \u0110\u1ed9, In\u0111\u00f4n\u00eaxia, Braxin v\u00e0 Vi\u1ec7t Nam. C\u00e0 ph\u00ea Vi\u1ec7t Nam c\u0169ng \u0111ang l\u00e0 m\u1ed9t m\u1eb7t h\u00e0ng xu\u1ea5t kh\u1ea9u c\u00f3 gi\u00e1 tr\u1ecb, ngo\u00e0i ra cao su, t\u1ebfch v\u00e0 m\u1ed9t s\u1ed1 lo\u00e0i c\u00e2y nh\u1eadp n\u1ed9i kh\u00e1c c\u0169ng \u0111ang \u0111\u01b0\u1ee3c \u01b0u ti\u00ean ph\u00e1t tri\u1ec3n m\u1edf r\u1ed9ng di\u1ec7n t\u00edch g\u00e2y tr\u1ed3ng.<strong>4. Ngh\u1ecbch l\u00fd th\u1ee9 t\u01b0 : Kh\u00f3 g\u00e2y tr\u1ed3ng ph\u00e1t tri\u1ec3n c\u00e2y b\u1ea3n \u0111\u1ecba<\/strong> ?\u0110i\u1ec1u r\u1ea5t \u0111\u00e1ng \u0111\u01b0\u1ee3c quan t\u00e2m l\u00e0 v\u1ed1n c\u00e2y b\u1ea3n \u0111\u1ecba hi\u1ec7n \u0111ang b\u1ecb suy gi\u1ea3m nghi\u00eam tr\u1ecdng c\u1ea3 v\u1ec1 ch\u1ee7ng lo\u1ea1i v\u00e0 s\u1ed1 l\u01b0\u1ee3ng do c\u00e1c ho\u1ea1t \u0111\u1ed9ng ph\u00e1 r\u1eebng. R\u1eebng l\u00e1 r\u1ed9ng th\u01b0\u1eddng xanh \u0111ang ng\u00e0y m\u1ed9t thu h\u1eb9p v\u00e0 d\u1ea7n bi\u1ebfn th\u00e0nh \u0111\u1ed3i tr\u1ecdc. M\u00f4i tr\u01b0\u1eddng s\u1ed1ng b\u1ecb ph\u00e1 hu\u1ef7, c\u00e1c h\u1ec7 sinh th\u00e1i r\u1eebng b\u1ecb \u0111e do\u1ea1, c\u00e1c lo\u00e0i \u0111\u1ed9ng th\u1ef1c v\u1eadt r\u1eebng qu\u00fd hi\u1ebfm \u0111ang \u0111\u1ee9ng tr\u01b0\u1edbc nguy c\u01a1 b\u1ecb tuy\u1ec7t ch\u1ee7ng. Vi\u1ec7c ph\u1ee5c h\u1ed3i r\u1eebng b\u1eb1ng c\u00e1c lo\u00e0i c\u00e2y b\u1ea3n \u0111\u1ecba \u0111ang tr\u1edf th\u00e0nh m\u1ed9t v\u1ea5n \u0111\u1ec1 c\u1ea5p b\u00e1ch. Song c\u00f3 m\u1ed9t ngh\u1ecbch l\u00fd kh\u00f3 gi\u1ea3i quy\u1ebft : g\u00e2y tr\u1ed3ng ph\u00e1t tri\u1ec3n c\u00e2y b\u1ea3n \u0111\u1ecba l\u00e0 m\u1ed9t c\u00f4ng vi\u1ec7c r\u1ea5t kh\u00f3 kh\u0103n. \u0110i\u1ec1u g\u00ec \u0111\u00e3 l\u00e0m cho v\u1ea5n \u0111\u1ec1 tr\u1edf n\u00ean ph\u1ee9c t\u1ea1p v\u00e0 kh\u00f3 gi\u1ea3i quy\u1ebft \u0111\u1ebfn nh\u01b0 th\u1ebf ?<strong>* C\u00e1c l\u00fd do v\u1ec1 hi\u1ec3u bi\u1ebft<\/strong> : Ch\u00fang ta c\u00f2n thi\u1ebfu nhi\u1ec1u hi\u1ec3u bi\u1ebft s\u00e2u s\u1eafc v\u1ec1 c\u00e1c h\u1ec7 sinh th\u00e1i r\u1eebng, c\u00e1c lo\u00e0i b\u1ea3n \u0111\u1ecba n\u00f3i chung v\u00e0 \u0111\u1eb7c \u0111i\u1ec3m ri\u00eang cho t\u1eebng lo\u00e0i c\u1ee5 th\u1ec3 nh\u01b0 nhu c\u1ea7u v\u1ec1 \u0111\u1ea5t \u0111ai, kh\u00ed h\u1eadu, \u00e1nh s\u00e1ng \u1edf c\u00e1c giai \u0111o\u1ea1n kh\u00e1c nhau, m\u1ed1i li\u00ean h\u1ec7 gi\u1eefa c\u00e1c lo\u00e0i trong qu\u1ea7n th\u1ec3 \u0111a lo\u00e0i, kh\u1ea3 n\u0103ng t\u00e1i sinh t\u1ef1 nhi\u00ean, kh\u1ea3 n\u0103ng g\u00e2y tr\u1ed3ng, v\u1eadt h\u1eadu v.v. V\u1edbi nh\u1eefng l\u1ed7 h\u1ed5ng l\u1edbn v\u1ec1 hi\u1ec3u bi\u1ebft nh\u01b0 v\u1eady ch\u1eafc ch\u1eafn kh\u00f3 c\u00f3 th\u1ec3 ph\u00e1t tri\u1ec3n c\u00e2y b\u1ea3n \u0111\u1ecba tr\u00ean di\u1ec7n r\u1ed9ng.<strong><\/strong><strong>* C\u00e1c l\u00fd do v\u1ec1 nh\u1eadn th\u1ee9c<\/strong> : C\u00e1c nh\u00e0 qu\u1ea3n l\u00fd mong mu\u1ed1n nhanh ch\u00f3ng \u0111\u01b0a nhanh c\u00e1c lo\u00e0i c\u00e2y b\u1ea3n \u0111\u1ecba v\u00e0o g\u00e2y tr\u1ed3ng \u0111\u1ea1i tr\u00e0, song \u0111\u1ed1i v\u1edbi c\u00e1c nh\u00e0 s\u1ea3n xu\u1ea5t kinh doanh, khai th\u00e1c l\u00e0 d\u1ec5 h\u01a1n c\u1ea3, c\u00f2n tr\u1ed3ng r\u1eebng v\u1edbi lu\u00e2n k\u1ef3 50 n\u0103m (ho\u1eb7c h\u01a1n n\u1eefa) l\u00e0 qu\u00e1 d\u00e0i \u0111\u1ed1i v\u1edbi h\u1ecd, trong khi l\u00e3i su\u1ea5t ng\u00e2n h\u00e0ng cao, hi\u1ec3m ho\u1ea1 \u0111\u1ed1i v\u1edbi lo\u1ea1i r\u1eebng n\u00e0y l\u1ea1i l\u1edbn, v\u00ec v\u1eady h\u1ecd ch\u1ec9 \u0111\u1ea7u t\u01b0 v\u00e0o c\u00e1c lo\u00e0i c\u00e2y c\u00f3 lu\u00e2n k\u1ef3 ng\u1eafn (5-7 n\u0103m) nhanh ch\u00f3ng thu s\u1ea3n ph\u1ea9m cho c\u00f4ng nghi\u1ec7p v\u00e0 xu\u1ea5t kh\u1ea9u \u0111\u1ec3 s\u1edbm thu h\u1ed3i v\u1ed1n v\u00e0 c\u00f3 l\u00e3i. Ai s\u1ebd l\u00e0 ng\u01b0\u1eddi \u0111\u1ea7u t\u01b0 cho c\u00e2y b\u1ea3n \u0111\u1ecba ? R\u00f5 r\u00e0ng Ch\u00ednh ph\u1ee7 ph\u1ea3i l\u00e0 nh\u00e2n t\u1ed1 ch\u1ee7 \u0111\u1ea1o.<strong><\/strong><strong>* C\u00e1c l\u00fd do v\u1ec1 k\u1ef9 thu\u1eadt<\/strong> : C\u00e2y b\u1ea3n \u0111\u1ecba quen s\u1ed1ng trong m\u1ed9t m\u00f4i tr\u01b0\u1eddng s\u1ed1ng ho\u00e0n ch\u1ec9nh, \u00edt bi\u1ebfn \u0111\u1ed9ng n\u00ean c\u00f3 nhu c\u1ea7u cao v\u1ec1 \u0111\u1ea5t v\u00e0 c\u00e1c y\u1ebfu t\u1ed1 kh\u00e1c. Kh\u00f4ng th\u1ec3 \u0111\u01b0a tr\u1ed3ng ngay c\u00e2y b\u1ea3n \u0111\u1ecba tr\u00ean \u0111\u1ea5t tr\u1ed1ng, \u0111\u1ed3i n\u00fai tr\u1ecdc kh\u00f4 c\u1eb1n, tr\u1ed3ng thu\u1ea7n lo\u1ea1i tr\u00e0n lan tr\u00ean di\u1ec7n r\u1ed9ng. Do tu\u1ed5i th\u1ecd d\u00e0i, hi\u1ec3u bi\u1ebft thi\u1ebfu, k\u1ef9 thu\u1eadt ch\u01b0a \u0111\u1ed3ng b\u1ed9 n\u00ean kh\u1ea3 n\u0103ng th\u00e0nh r\u1eebng khi tr\u1ed3ng c\u00e2y b\u1ea3n \u0111\u1ecba thu\u1ea7n lo\u1ea1i tr\u00ean di\u1ec7n r\u1ed9ng l\u00e0 kh\u00f3 nh\u01b0 tr\u01b0\u1eddng h\u1ee3p r\u1eebng m\u1ee1 (<em>Manglietia glauca<\/em>) v\u00e0 l\u00e1t hoa (<em>Chukrasia tabularis<\/em>) cho g\u1ed7 l\u1edbn trong nh\u1eefng n\u0103m v\u1eeba qua. R\u1eebng tr\u1ed3ng b\u1ed3 \u0111\u1ec1 (<em>Styrax tonkinensis<\/em>) r\u1ea5t th\u00e0nh c\u00f4ng \u1edf lu\u00e2n k\u1ef3 \u0111\u1ea7u song n\u0103ng su\u1ea5t gi\u1ea3m d\u1ea7n \u1edf c\u00e1c lu\u00e2n k\u1ef3 sau m\u00e0 ch\u01b0a c\u00f3 c\u00e1c bi\u1ec7n ph\u00e1p gi\u1ea3i quy\u1ebft tho\u1ea3 \u0111\u00e1ng. Ai c\u0169ng bi\u1ebft nghi\u00ean c\u1ee9u c\u1ea7n ph\u1ea3i \u0111i tr\u01b0\u1edbc m\u1ed9t b\u01b0\u1edbc song \u0111\u1ea7u t\u01b0 cho nghi\u00ean c\u1ee9u c\u00e1c v\u1ea5n \u0111\u1ec1 n\u00e0y c\u00f2n qu\u00e1 th\u1ea5p.<strong>* C\u00e1c l\u00fd do v\u1ec1 x\u00e3 h\u1ed9i<\/strong> : V\u00f9ng c\u00f3 nhu c\u1ea7u l\u1edbn v\u1ec1 tr\u1ed3ng c\u00e2y b\u1ea3n \u0111\u1ecba th\u01b0\u1eddng l\u00e0 v\u00f9ng s\u00e2u v\u00f9ng xa, \u0111\u1eddi s\u1ed1ng c\u1ee7a d\u00e2n c\u00f2n g\u1eb7p nhi\u1ec1u kh\u00f3 kh\u0103n, giao th\u00f4ng y\u1ebfu, \u0111i\u1ec1u ki\u1ec7n \u0111\u1ec3 ti\u1ebfp thu k\u1ef9 thu\u1eadt m\u1edbi c\u00f2n nhi\u1ec1u h\u1ea1n ch\u1ebf. Quy ho\u1ea1ch \u0111\u1ea5t r\u1eebng, b\u1ea3o v\u1ec7 r\u1eebng, \u0111\u1ea5t cho tr\u1ed3ng r\u1eebng, tr\u1ed3ng r\u1eebng g\u00ec v.v. \u1edf c\u00e1c \u0111\u1ecba ph\u01b0\u01a1ng c\u00f2n ch\u01b0a c\u1ee5 th\u1ec3. Ng\u01b0\u1eddi d\u00e2n v\u1eabn ph\u00e1 r\u1eebng l\u1ea5y \u0111\u1ea5t tr\u1ed3ng c\u00e2y c\u00f4ng nghi\u1ec7p v\u00e0 c\u00e2y l\u01b0\u01a1ng th\u1ef1c. V\u1ed1n cho tr\u1ed3ng r\u1eebng thi\u1ebfu, d\u00e2n ch\u01b0a mu\u1ed1n tr\u1ed3ng r\u1eebng lu\u00e2n k\u1ef3 d\u00e0i v\u00e0 r\u1eebng hi\u1ec7n c\u00f2n kh\u00f3 b\u1ea3o v\u1ec7. M\u1ed9t s\u1ed1 n\u01a1i \u0111\u00e3 c\u00f3 \u0111\u1ea7u t\u01b0 c\u1ee7a Nh\u00e0 n\u01b0\u1edbc cho tr\u1ed3ng r\u1eebng c\u00e2y b\u1ea3n \u0111\u1ecba song m\u1ee9c \u0111\u1ea7u t\u01b0 c\u00f2n th\u1ea5p, tr\u1ed3ng qu\u1ea3ng canh, ch\u01b0a tu\u00e2n th\u1ee7 c\u00e1c y\u00eau c\u1ea7u k\u1ef9 thu\u1eadt.NGH\u1ecbCH L\u00fd C\u1ee7A NGH\u1ecbCH L\u00fd : \u0110\u1ecbNHH\u01af\u1edbNGGI\u1ea3IQUY\u1ebfT.V\u1edbi kinh nghi\u1ec7m qu\u00fd thu \u0111\u01b0\u1ee3c t\u1eeb h\u00e0ng tr\u0103m n\u0103m v\u00e0 35 n\u0103m x\u00e2y d\u1ef1ng ng\u00e0nh L\u00e2m nghi\u1ec7p, h\u00e0ng ch\u1ee5c lo\u00e0i c\u00e2y b\u1ea3n \u0111\u1ecba \u0111\u00e3 \u0111\u01b0\u1ee3c \u0111\u01b0a v\u00e0o tr\u1ed3ng r\u1eebng th\u00e0nh c\u00f4ng \u1edf c\u00e1c m\u1ee9c \u0111\u1ed9 v\u00e0 ph\u1ea1m vi kh\u00e1c nhau. H\u00e0ng ch\u1ee5c lo\u00e0i c\u00e2y \u0111\u00e3 c\u00f3 \u0111\u01b0\u1ee3c quy tr\u00ecnh, quy ph\u1ea1m ho\u1eb7c h\u01b0\u1edbng d\u1eabn k\u1ef9 thu\u1eadt g\u00e2y tr\u1ed3ng. H\u1ed3i \u1edf L\u1ea1ng S\u01a1n v\u00e0 qu\u1ebf \u1edf Y\u00ean B\u00e1i \u0111\u00e3 t\u1eebng \u0111\u01b0\u1ee3c ng\u01b0\u1eddi d\u00e2n \u0111\u1ecba ph\u01b0\u01a1ng g\u00e2y tr\u1ed3ng th\u00e0nh c\u00f4ng t\u1eeb h\u00e0ng tr\u0103m n\u0103m qua v\u00e0 c\u00f2n \u0111\u01b0\u1ee3c m\u1edf r\u1ed9ng sang c\u00e1c \u0111\u1ecba ph\u01b0\u01a1ng l\u00e2n c\u1eadn. Lim xanh \u0111\u00e3 \u0111\u01b0\u1ee3c tr\u1ed3ng t\u1eeb h\u00e0ng ch\u1ee5c n\u0103m nay t\u1ea1i nhi\u1ec1u \u0111\u1ecba ph\u01b0\u01a1ng nh\u01b0 Thanh h\u00f3a, Ho\u00e0 B\u00ecnh, Tam \u0110\u1ea3o (V\u0129nh Ph\u00fac), C\u1ea7u Hai (Ph\u00fa Th\u1ecd), k\u1ec3 c\u1ea3 m\u1ed9t s\u1ed1 n\u01a1i ngo\u00e0i v\u00f9ng ph\u00e2n b\u1ed1 c\u1ee7a lo\u00e0i nh\u01b0 Lang Hanh (L\u00e2m \u0110\u1ed3ng), Tr\u1ea3ng Bom (\u0110\u1ed3ng Nai). B\u1ed3 \u0111\u1ec1 v\u00e0 m\u1ee1 \u0111\u00e3 t\u1eebng l\u00e0 c\u00e1c lo\u00e0i c\u00e2y tr\u1ed3ng r\u1eebng ch\u00ednh c\u1ee7a v\u00f9ng trung t\u00e2m v\u00e0 \u0110\u00f4ng B\u1eafc B\u1ed9. Th\u00f4ng nh\u1ef1a th\u00e0nh lo\u00e0i c\u00e2y ph\u1ee7 xanh quen thu\u1ed9c c\u1ee7a v\u00f9ng trung du mi\u1ec1n B\u1eafc v\u00e0 Trung b\u1ed9 m\u00e0 ch\u1ec9 c\u00f3 n\u00f3 m\u1edbi ch\u1ecbu n\u1ed5i nh\u1eefng \u0111\u1ed3i \u0111\u00e1 ong kh\u00f4 c\u1eb1n. Tr\u1ea9u, s\u1edf \u0111\u00e3 t\u1eebng \u0111\u01b0\u1ee3c tr\u1ed3ng \u1edf nhi\u1ec1u n\u01a1i c\u1ee7a v\u00f9ng n\u00fai mi\u1ec1n B\u1eafc v\u00e0 B\u1eafc Trung B\u1ed9; c\u0169ng nh\u01b0 th\u00f4ng ba l\u00e1 \u1edf T\u00e2y Nguy\u00ean; sao, d\u1ea7u \u1edf Nam B\u1ed9; c\u00e1c c\u00e2y ch\u1ee7 c\u00e1nh ki\u1ebfn \u0111\u1ecf (c\u1ecd ph\u00e8n, c\u1ecd khi\u1ebft, \u0111\u1eadu thi\u1ec1u) \u1edf T\u00e2y B\u1eafc.Nh\u1eefng n\u0103m g\u1ea7n \u0111\u00e2y, nhi\u1ec1u lo\u00e0i c\u00e2y kh\u00e1c c\u0169ng \u0111\u00e3 \u0111\u01b0\u1ee3c th\u1eed nghi\u1ec7m tr\u00ean nhi\u1ec1u d\u1ea1ng l\u1eadp \u0111\u1ecba v\u00e0 kh\u00ed h\u1eadu nh\u01b0 c\u1ea9m lai \u1edf \u0110\u00f4ng Nam B\u1ed9; g\u00f5 \u0111\u1ecf v\u00e0 b\u1eddi l\u1eddi \u0111\u1ecf \u1edf T\u00e2y Nguy\u00ean, tr\u1ea7m h\u01b0\u01a1ng \u1edf mi\u1ec1n Trung; m\u1ea1y sao, h\u00f4ng, kh\u00e1o v\u00e0ng, d\u1ebb \u0111\u1ecf, d\u1ebb \u0103n qu\u1ea3 \u1edf v\u00f9ng \u0110\u00f4ng B\u1eafc, t\u00e1o m\u00e8o \u1edf T\u00e2y B\u1eafc; l\u00e1t hoa \u1edf S\u01a1n La, Ho\u00e0 B\u00ecnh v\u00e0 Ngh\u1ec7 An; hu\u1ef7nh \u1edf Qu\u1ea3ng B\u00ecnh v\u00e0 c\u00e1c lo\u00e0i tre lu\u1ed3ng, song m\u00e2y \u1edf r\u1ea3i r\u00e1c nhi\u1ec1u n\u01a1i.R\u1eebng lim xanh 35 tu\u1ed5i tr\u1ed3ng t\u1ea1i C\u1ea7u Hai (\u0110oan H\u00f9ng, Ph\u00fa Th\u1ecd) n\u0103m 1961 nay c\u00f3 chi\u1ec1u cao b\u00ecnh qu\u00e2n 15 m v\u00e0 \u0111\u01b0\u1eddng k\u00ednh b\u00ecnh qu\u00e2n 39,5 cm (m\u1eadt \u0111\u1ed9 ban \u0111\u1ea7u 1100 c\u00e2y\/ha qua nhi\u1ec1u l\u1ea7n ch\u1eb7t t\u1ec9a nay c\u00f2n 100 c\u00e2y\/ha). Nguy\u1ec5n B\u00e1 Ch\u1ea5t (1996) th\u00f4ng b\u00e1o r\u1eb1ng l\u00e1t hoa tr\u1ed3ng trong b\u0103ng r\u1ed9ng 20 m sau 4 n\u0103m cho chi\u1ec1u cao v\u00fat ng\u1ecdn 5,5 m v\u00e0 \u0111\u01b0\u1eddng k\u00ednh ngang ng\u1ef1c 5,4 cm. B\u1ea3ng 1 gi\u1edbi thi\u1ec7u m\u1ed9t s\u1ed1 s\u1ed1 li\u1ec7u t\u0103ng tr\u01b0\u1edfng chi\u1ec1u cao v\u00e0 \u0111\u01b0\u1eddng k\u00ednh ngang ng\u1ef1c c\u1ee7a m\u1ed9t s\u1ed1 lo\u00e0i c\u00e2y b\u1ea3n \u0111\u1ecba \u0111\u01b0\u1ee3c tr\u1ed3ng trong v\u01b0\u1eddn s\u01b0u t\u1eadp c\u00e2y g\u1ed7 \u1edf C\u1ea7u Hai, Ph\u00fa Th\u1ecd v\u00e0 r\u1eebng tr\u1ed3ng \u1edf m\u1ed9t s\u1ed1 n\u01a1i kh\u00e1c.B\u1ea3ng 1 : T\u0103ng tr\u01b0\u1edfng c\u1ee7a m\u1ed9t s\u1ed1 lo\u00e0i c\u00e2y b\u1ea3n \u0111\u1ecba tr\u1ed3ng \u1edf m\u1ed9t s\u1ed1 n\u01a1i. <\/p>\n<table>\n<tbody>\n<tr>\n<td>lo\u00e0i<\/td>\n<td>\ntu\u1ed5i (n\u0103m)\n<\/td>\n<td>\nt\u0103ng tr\u01b0\u1edfng D 1,3(cm\/n\u0103m)\n<\/td>\n<td>\nt\u0103ng tr\u01b0\u1edfng H (m\/n\u0103m)\n<\/td>\n<td>\u0111\u1ecba ph\u01b0\u01a1ng<\/td>\n<\/tr>\n<tr>\n<td>Lim xanh<\/td>\n<td>35<\/td>\n<td>1,09<\/td>\n<td>0,35<\/td>\n<td>Tam \u0110\u1ea3o,V\u0129nh Ph\u00fac<\/td>\n<\/tr>\n<tr>\n<td>Lim xanh<\/td>\n<td>35<\/td>\n<td>1,13<\/td>\n<td>0,43<\/td>\n<td>C\u1ea7u Hai, Ph\u00fa Th\u1ecd<\/td>\n<\/tr>\n<tr>\n<td>Lim xanh<\/td>\n<td>5<\/td>\n<td>1,46<\/td>\n<td>1,08<\/td>\n<td>C\u1ea7u Hai, Ph\u00fa Th\u1ecd<\/td>\n<\/tr>\n<tr>\n<td>Lim x\u1eb9t<\/td>\n<td>5<\/td>\n<td>1,73<\/td>\n<td>1,29<\/td>\n<td>C\u1ea7u Hai, Ph\u00fa Th\u1ecd<\/td>\n<\/tr>\n<tr>\n<td>R\u00e0ng r\u00e0ng m\u00edt<\/td>\n<td>5<\/td>\n<td>1,20<\/td>\n<td>1,25<\/td>\n<td>C\u1ea7u Hai, Ph\u00fa Th\u1ecd<\/td>\n<\/tr>\n<tr>\n<td>V\u1ea1ng tr\u1ee9ng<\/td>\n<td>5<\/td>\n<td>2,16<\/td>\n<td>1,59<\/td>\n<td>C\u1ea7u Hai, Ph\u00fa Th\u1ecd<\/td>\n<\/tr>\n<tr>\n<td>S\u1ed3i ph\u1ea3ng<\/td>\n<td>5<\/td>\n<td>2,54<\/td>\n<td>1,51<\/td>\n<td>C\u1ea7u Hai, Ph\u00fa Th\u1ecd<\/td>\n<\/tr>\n<tr>\n<td>Re g\u1eebng<\/td>\n<td>5<\/td>\n<td>1,86<\/td>\n<td>1,27<\/td>\n<td>C\u1ea7u Hai, Ph\u00fa Th\u1ecd<\/td>\n<\/tr>\n<tr>\n<td>L\u00e1t hoa *<\/td>\n<td>4<\/td>\n<td>1,35<\/td>\n<td>1,37<\/td>\n<td>Ngh\u0129a \u0110\u00e0n, Ngh\u1ec7 An<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Nh\u01b0 v\u1eady c\u00f3 th\u1ec3 th\u1ea5y r\u1ea5t r\u00f5 r\u1eb1ng vi\u1ec7c g\u00e2y tr\u1ed3ng c\u00e2y b\u1ea3n \u0111\u1ecba \u0111\u00e3 c\u00f3 ti\u1ec1m n\u0103ng l\u1edbn v\u00e0 c\u00f3 th\u1ec3 th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c song kh\u00f4ng ph\u1ea3i lo\u00e0i c\u00e2y n\u00e0o v\u00e0 n\u01a1i n\u00e0o c\u0169ng th\u00e0nh c\u00f4ng. X\u00e1c \u0111\u1ecbnh lo\u00e0i c\u00e2y th\u00edch h\u1ee3p, ch\u1ecdn ho\u00e0n c\u1ea3nh g\u00e2y tr\u1ed3ng ph\u00f9 h\u1ee3p (\u0111\u1ea5t \u0111ai v\u00e0 kh\u00ed h\u1eadu), t\u1ea1o ho\u00e0n c\u1ea3nh tr\u1ed3ng v\u00e0 ch\u1ecdn ph\u01b0\u01a1ng th\u1ee9c tr\u1ed3ng c\u0169ng nh\u01b0 x\u00e1c \u0111\u1ecbnh r\u00f5 ngu\u1ed3n gi\u1ed1ng ph\u00f9 h\u1ee3p s\u1ebd l\u00e0 nh\u1eefng \u0111i\u1ec1u ki\u1ec7n c\u01a1 b\u1ea3n c\u1ee7a th\u00e0nh c\u00f4ng. <\/p>\n","protected":false},"excerpt":{"rendered":"<p><span style=\"font-family: &#39;Times New Roman&#39;\"><font size=\"3\">R\u1eebng t\u1ef1 nhi&ecirc;n c\u1ee7a c&aacute;c n\u01b0\u1edbc nhi\u1ec7t \u0111\u1edbi c&oacute; m\u1ee9c \u0111\u1ed9 \u0111a d\u1ea1ng cao v\u1ec1 c&aacute;c lo&agrave;i th\u1ef1c v\u1eadt. Theo nh&agrave; khoa h\u1ecdc van Steenis (1971) th&igrave; v&ugrave;ng \u0110&ocirc;ng Nam &aacute; bao g\u1ed3m c\u1ea3 Vi\u1ec7t Nam, c&oacute; t\u1edbi 25 000 lo&agrave;i th\u1ef1c v\u1eadt c&oacute; hoa, chi\u1ebfm 10% t\u1ed5ng s\u1ed1 lo&agrave;i th\u1ef1c v\u1eadt c&oacute; hoa c\u1ee7a th\u1ebf gi\u1edbi, trong \u0111&oacute; c&oacute; t\u1edbi 40% s\u1ed1 lo&agrave;i l&agrave; lo&agrave;i \u0111\u1eb7c h\u1eefu, ngh\u0129a l&agrave; ch\u1ec9 g\u1eb7p \u1edf ri&ecirc;ng v&ugrave;ng n&agrave;y m&agrave; th&ocirc;i.<\/font><\/span><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[21],"tags":[],"_links":{"self":[{"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/posts\/8948"}],"collection":[{"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/comments?post=8948"}],"version-history":[{"count":1,"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/posts\/8948\/revisions"}],"predecessor-version":[{"id":10404,"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/posts\/8948\/revisions\/10404"}],"wp:attachment":[{"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/media?parent=8948"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/categories?post=8948"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/tags?post=8948"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}