- Phiro'ng phap quan sat, do dac: Bang kinh nghiem ctia minh, ket hgp
b. Tdc dgng cua dieu kien khi hau, moi trudng
- Su thich nghi eua cdy trong dieu kien mdi trudng do thi
Nhu chiing ta da biet phan Idn cay bdng mat trdng d Ha Ndi dugc dem ve ttr rirng ty nhien. Vi vay nhirng cay nio thich nghi dugc se tdn tai va phat trien, nguge lai se bj dao thai.
Da phan nhu'ng loai cay ban dja cd ngudn gdc d Viet Nam cd kha nang thich nghi tdt ban nhu Mudm, Lim xanh, Ldc virng, Nhdi, Sanh, Si, Sau. Sua, Stra. Dau rai. Nhti'ng loai cay nay tuy da budc vao tudi cd thiJ nhung kha nang sinh trtrdng van binh thudng, it sau benh rdng rudt. Tuy vay cting cd mgt vai loai thich nghi
Xdy dung Atlas cdy cd thu Hd Ndi
kem nhu: Bang lang nudc. Me, Vti stra. Sao den... thudng sau benh. muc gdc. cinh d tudi gia.
Nhung cay nhap ngi dugc dua ttr nbtrng nudc cd cting dieu kien khi hau nhiet ddi hay i nhiet ddi. khi trdng d Ha Ndi da cd nbtrng sy thich. nghi khic nhau. Mdt sd cay den tudi gia da ed hien tugng muc gdc, rdng rudt, gay canh. Dien hinh nhu cay: Dii ngya, Phugng vT, Mudng ngti. But mgc. Ngan hoa... Nhung ca\ na> cdn sdt lai rat it, va thudng hay dd gay vao mtia mua bao. Tuy \ay trong sd nbtrng loai cay nhap ndi ndi len loii cay Xi ctr. Xa ctr thich nghi vdi dieu kien sdng d Ha Ndi ca ve dat dai vi khi hiu. Bang chirng la cay sinh trudng nhanh, phat trien tdt ca ve chieu cao va dudng kinh. Trong dieu kien phit trien binh thudng, it bi tic ddng cat tia cay se rat to cao, tan phit trien rdng. Cbting ta cd the thay mdt sd cay d Bach Thio, hay tren dudng phd Ha Ndi. Dien hinh la cay X i ctr trirdc Phti Chti tjch cd chu vi than cay 5,72in, tire dudng kinh than cay l,82tn, d Vudn Bach thio cd 2 cay cd dudng kinh 1,77m. Xa ctr mac dti nhieu cay da qua 100 tudi nhung chua thay cd bieu hien cita sy gia cdi, cay phat trien tdt khdng muc than, gdc, it sau benh cho dti Xa ctr la loii cay bi cat tia rat nhieu. Xa ctr cd be re ngang rat phat trien dim bao cho sy vung chac ctia cay. Nhung tren dudng phd Ha Ndi Xa ctr hay bj dd trong mtia gid bao va bj bai xich. Chinh vi trong qui trinh stra he phd, xay dyng cic cdng trinh ngam ngudi ta da chat bd he re ciia cay, lam cay mat can bang v i de dd. Cdn d nhirng noi thdng thoing, he re phit trien hoan chinh ngay c i khi tan cay rat phat trien, X i ctr chua bao gid dd.
Qua viec nhap ngi gidng cay trdng tao bdng mat cho Ha Ngi, can phai cd nbtrng budc di than trgng va nghien ctru can than, bdi vi cay bdng mat phii sau vai chuc nam chung mdi phat huy tic dyng va nbtrng hau qua chung mang lai chua the dy tinh dugc.
- Thdi tiet gid bdo
Ha Ndi nam trong viing khi hau nhiet ddi am, mua mtia. Hang nam thudng xay ra nbtrng con ldc, gid manh, mua Idn ddi khi cd bao. H i Ndi da chirng kien tran bao di qua lam dd hang tram cay gd Idn, nbtrng con ldc lam dd nhieu cay va nhtrng
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Xdy dirng Alias cdy cd thu Hd Ndi
con mua Idn lam ngap sau nhieu dudng phd. Nhti'ng tie ddng nay qua thdi gian da anh hudng nhieu den sy phit trien va tdn tai ctia he thdng ca\ bdng mat.
Nbtrng cay gia. cay cd thu d Ha Ndi cdn dugc den nga\ na> cting da \ugt qua nbtrng tic dgng khac nghiet ciia thai tiet thien nhien de tdn tai va phat trien.