Mfii Pia ly v^ Tai Dguyen M5i trufrng Thira Thien H u i Hpi P i a ly Vifl Nam
Thipac do tham hut sinh thai va dip trir sinh thai:
mo hinh va i>ng dung cho thanh phd Ha Noi
Nguyen An Thjnh', Tran VSn Tuan' Abstract
Ecological deficit and ecological reserve: model and its application for Hanoi city Recent decades have seen a greater consumption of human caused the degradation of natural ecosystems' production capacity at multiscales over the world. This ecological reality could be clarified by using several quaniiialive indicators, such as ecological deficu and ecological reserve Considering as the biggest city in Vietnam since Us expansion in 2008, Hanoi city has a rapid urbanization and an increased consumption which have affected negatively natural resources and sustainable development alreaify Results of applying ecological deficit and ecological reserve to Hanoi city included of calculating values of equivalence factors (EQF) and yield factor (YF) for different land uses, assessing ecological defied and ecological reserve, and analyzing impacts of urbanization and land use planning as principal human driving forces of raising ecological reserve These results show that three quarters of districts in Hanoi rank among ecological defied group, furihermore, applications of ecological deficit and ecological reserve would be indicated as a scientific base for
land use planning in Hanoi city until 2020 in terms of sustainable development as well as climate change adaptation
L D A T VAN D E
Trong nhung thap ky gan day, van de con ngudi dang lam tang nhu cau tieu thy vugt qua kha nang cung ung ciia he sinh thai hoac khai thac qua mirc cac ngudn tai nguyen thien nhien - nhu'ng khia cgnh quan trgng phan anh mirc do bin viing mdi Irudng cua mgt khu vuc - da dugc de cap tdi trong nhieu tai li?u [3, 5]. Tuy nhien, Iheo Idng hgp cua Ewing va nnk. (2010), tren thyc te kh6ng cd nhieu n^ien ciiu minh ehirng cho cac nhan djnh dd [4]. Hudng danh gia tham hut sinh thai (ecological deficit) va dy IrO sinh thai (ecological reserve) dya tren cac ehi thi djnh lugng ciia td chiic Mang ludi Diu chan Toan ciu (Global Footprint Network) la mgt each tilp can hieu qua giai quylt bai toan nay.
Cac Ihudc do nay dugc ap dyng cho pham vi toan cau, cap qudc gia va dja phuong; tinh den cuoi nam 2010 da dugc danh gia eho ban 100 thanh phd thugc tat ca cac chau luc tren thi gidi [3, 4, 6, 8,9].
Sau khi dugc md rgng dja gidi hanh chinh vao thang 8/2008, thanh phd Ha Ndi cd tdng dien tich 3.348,5 km^, bao gdm 29 quan, huyen vdi 577 phudng, xa va thj Iran, trd thanh mdt trong 17 thii do cd dien tich ldn nhit the gidi. Md rdng dja gidi mgt mat bao dam khdng gian cho phat trien kinh te xa hdi, mat khac, nhilu van dl nay sinh lien quan Idi dd thj hda nhanh, chuyen ddi muc dich sir dyng dal theo hudng giam dien tich cac loai dat co kha nang san xuat, gia lang tieu thu luong thyc va nhien li?u.... tgo ap luc ldn ddi vdi Iai nguyen, thach thirc phat trien ben virng. Do dd, danh gia thuc trang tham hyt sinh thai va dy trir sinh thai de thay dugc su khac biel vl kha nang cung ung tai nguyen so vdi nhu ciu tieu thu giiJa cac quan, huyen cd y nghTa quan trgng cho djnh hudng phal trien ciia thanh pho Ha Npi nhiJng nam tiep theo.
2. CACH TIEP CAN VA MO HINH
' Trudng Dgi hqc Khoa hoc Tu nhien. DHQG Hd NQI
D!A LY TUNHIEN, TAI NGUYEN THIEN NHIEN VA MOI TRUONG
Hoi Dja ly v^ Tai ngu}cn Moi trirong Thua Thien Hue Hpi Dja ly Vigt M,
Dugc sir dung rdng rai nhu cac chi thj ve tinh ben vung mdi trudng, thudc do tham hut sinh \\
phan anh "'mirc do tieu ihu tdi nguyen vd dong hda chdt thdi cua con ngudi vugl qud khd ndng cu.
img cua dia phucmg hodc khu virc", ngugc Igi, thudc do du tru sinh thai bieu thj "khd ndng cung •i, lai nguyen cua dia phirang hodc khu virc ldn han muc dg Uiu ihg tdi nguyen ciia con ngudi" [4], Di tren so sanh nhu cau eiia con ngudi vdi muc dap ung ciia ly nhien, tham hyl sinh thai se xay ra iroi trudng hgp nhu cau ldn hon, ngugc lai se xay ra tich luy sinh thai.
Mdt md hinh duge khuyen nghj su dyng cho cap dja phuong vdi dicn tich cac logi dat duoc quy doi' Cling mdt don vj chuan la hecta loan cau (gha) Ihdng qua hi sd cdn bdng va hi so ndng sudt [3, 4, 5] co d?i nhu sau:
ED = EQFy.YF>
vdi ED > 0: tham hyt sinh thai; ED < 0: tich Itiy sinh thai
Trong dd: ED la thudc do tham hut/du Irir sinh Ihai (gha/ngudi); EQF la he sd can bin (gha/Iia); YF la h? sd nang suat (tan/Iia); P la luong ticu thu san pham sinh hgc hoac lugng phal thi (tan); YN la he sd nang suat qudc gia (tan/ha); A la dien tich ciia tirng loai dat (ha)
Gia tri cac he sd nang suat YF dugc xac djnh theo mo hinh sau:
YF!; -r^-x(x„')"'
Trong do: YF^ la he sd nang suat (wha4dia); K^ la nang sua! loai dat quoc gia (laiVhha); ^^L nang suat logi dal tren the gidi (tan/wha),
3. CAC KET QUA NGHIEN c u t )
3.1. Xac djnh gia tri he so can bang va he so nang suat
He sd call bang EQF cho phep chuyin ddi dien tich 5 loai dit la dat canh lac, dat ddng c6 chai nudi, dat rirng, mgt nude nudi trdng thiiy san va dat xay dung tir don vi ha sang don vi gha, dugc tham khao tCr sd lieu ciia id chirc Mang ludi Diu chan Toan ciu khi ap dung cho thanh phd Ha Npi. Hes^
nang suat YF phan anh nang suat tuong doi dac tbii cho mfii qudc gia. Do tir nam 2002, to chirc Manj ludi Dau chan Toan cau khdng cdng bd cy Ihl gia tri YF cho tirng qudc gia [4, 5], nen Irong nghiei cuu nay sudung gia tri YF da dugc tinh cho VietNam vao nam 2001 (bdng 1).
Bang 1. Gid tri cdc hi sd dp dung cho thdnh phd Hd Ndi
Loai dat 1, Dat canh tac 2 Dac rirng 3 Diil donjicochan nuoi 4, Mat nirac nuoi Irong lliuy san 5. Dat xay dirn^
He so can bang EQF (Bha/ha)
2,51 1.26 0.46 0.37 2.51
He so nangsuSt YF(wha/nha)
1,66 1.53 1.22 1.00 1.66 3.2. Danh gia mure do tham hut sinh thai va dy Iru' sinh thai
Hoi nghi Khoa hoc Dia ly Todn qudc ldn thu 6; Thdnh phd Hui 9/201^
J... Pja ly va Tai nguyen Moi truo'ng Thti'a Thien Hue Hoi Oia ly Vict Nair
Thudc do tham hut sinh thai va dy tru' sinh thai Aaac sit dung danh gia cho tat ca 29 quan, huyen cua thanh phi Ha Npi vdi eac thdng sd dau vao duac thing ke nam 2009. Kit qua danh gia cho thay gia tri tham hut sinh thai trung binh (n) ciia Ihanh phd Ha Npi la 0,929 (gha/ngudi); gia tri tdi da la 7,115 gha/ngudi thuoc ve quan Hoan Kiem, gap 7,66 lan iri trung binh (ji); gia trj toi thicu la -0,301 gha/ngudi lhu6c vl huyen Ba Vi Cac khu vuc cd gia trj cao thupc vl Hoan Kiem, Cau Giay, Ba Dinh, Long Bien, Ha Dong va Hoai Due (ED > 2 gha/ngudi) Cac khu vyc CO gia trj thap thuoc ve cae huyen Chuang My, Thanh Oai, My Diic, Soc Son, Phii Xuyen, U'ng Hda va Ba Vi (ED < 0 gha/ngudi) (bang 2j.
Hinh 1. Sa dd mien gid tri thii-ac do ihdin hut s 'nh thai vd tich liiy sinh then cua thdnh phd Hd Noi
ndm2009
Tren ban dd mien gia trj, mat do dudng dang tn tham hut sinh thai eao nhit d cac quan ngi Ihanh vdi dinh nam d vj tri quan Hoan Kiem, nguoc lai, cac huyen ngoai thanh co gia tri Ihap han Khu virc thdm hut sinh that cao nhdl la quan Hoan Kiem (gia Irj ED = 7, U 5 gha/ngudi). Khu vuc thdm hut stnh thai cao bao gdm cac quan ndi thanh la Cau Giay, Ba Dinh, Long Bien, Ha Ddng va huyen Hoai Diic (ED = 2,083 - 2,519 gha/ngudi). phan anh nhu cau lieu thu tin nguyen Idn hon nhieu lan so vdi kha nang cung cap ciia dat dai. Khu vu-c thdm hut sinh thdi trung binh bao gom ba quan ngi thanh la Tay Ho, Thanh Xuan va Hai Ba Trung (ED = 1,039 ^ 1,605 gha/ngudi). Khu vuc cd muc do thdm hut thdp bao gdm quan Dong Da. thj xa Son Tay va eac huyen ngoai thanh la Me Linh, Dan Phugng, Thanh Tri, Tir Liem, Hoang Mai, Phuc Thg, Qudc Oai, Gia Lam, Ddng ih, Thach That va Thudng Tin (ED = 0,015 - 0,845 gha/ngudi). Khu vuc du tru sinh thdi gdm phan Idn cae huyen ngoai thanh thupc tinh Ha Tay (eu) la Chuong My, Thanli Oai, My Due, Sdc Son, Phii Xuyen, Ba Vi va Ung Hda (ED = -0,301 ^ -0,029). Vdi long dien tich ty nhien la 148.943 ha, cac huyen thugc khu vuc du trir sinh thai cd dien Iich dat canh tac chilm tdi 53.537 ha (35,9%) va dit rirng 19.315 ha (12,9%), gip nhieu Ian so vdi cac khu vuc tham hyt sinh thai (hhih I).
3.3. Tac dgng cua do thi hda va quy hoach su* dung dat den Iham hut sinh thai
Cac nghien cuu tgi nhieu dd Ihj tren the gidi cho thay, trong trudng hgp cae qudc gia dang phat trien, cae yeu to chu yeu eiia dd thj hda anh hudng den tham hyt sinh thai la miic dp tap trung dan cu va bien doi ca cau sir dyng dat [6, 7], Doi vdi thanh phd Ha Ngi, theo so lieu dicu tra dan so den 1/4/2009. long sd dan ciia Ha Ngi la 6.448,837 ngudi, mat do dan sd trung binh 1,979 ngudi/km^ vdi 2,632.087 cu dan thanh thj (41.8 l%)va 3.816.750 cu dan ndng thon (58,19%), Dan eu lap trung dong nhat tgi cac qugn ndi thanh nhu Hoan Kiem (28,02 nghin ngudi/km"), Ba Dinh (24,46 nghin ngudi/km ). Cac huyen ngogi thanh cd mat dp dan sd thap, vi du Chuang My (1,26 nghin ngudi/km"), Ung Hda (0,99 nghin ngudi/km^) [2]. Quan Hoan Kiem dugc xep vao nhdm cd mire dd tham hut sinh Ihai cao nhat, cd mat do dan sd 28,02 nghin ngudi/km", dat xay dyng chiein d\c<-' tich lan nhat. Khu vuc du triJ sinh thai bao gdm cac huyen ngoai thanh cd mat do dan sd thap nhal va dien tich dat canh tac chiem ty trgng ldn trong co cau sir dung dat.
B[A LY TU'NHIEN, TAI NGUYEN THIEN NHIEN VA MOI TRU'QNG
Hgi Dja Ly va Tki nguyen Moi trirong Thiia Thicn Hue Hoi Oia ly Vicl San,
Trong bao cao qiiy hoach sir dung dat thanh ph6 Ha Noi, d\r Itien nhom dat phi nong nghiep dfii, nam 2020 se dat dien tich 167.507 ha, tang 32.824 ha so voi nam 2010. Chiim do thj dirffc djnh hirmi|^
phat trien bao g3m do thi trung tam hat nhan va cac do thj trirc thuoc voi cac do thi v? tinh va 13 llij~
trSn, chu trpng ma rong ve phia tay va bic sang ta ngan song Mong. Cac trung tam do thi mot dirijQ quy hoach la do thi sinh thai Son Tay, do thi khoa hpc-cong ngh? Hoa Lac (Thach That), do thi djch vu dao tao Xuan Mai (Chuong My), do thi cong nghiep Phu Xuyen - Phu Minh (PhU Xuyen), do thj c6ng nghiep dich vy Soc Son [I]. Cac do thi trung tam nay deu thupc khu viic tham hut sinh thai ihip (Son Tay, Thach Thit) hoac dtr triJ sinh thai (Chirong My, Phu Xuyen, Soc Son). Nhir vjy. theo phuong an quy hoach, thi xa Son Tay va huyen Thach That dirpc d\r bao se co su thay doi ro ret vj mirc xep hang so voi cac huyen con lai trong nhom tham hut sinh thai thap; tuong tir, cac huyJi, Chirong MJ, Phil Xuyen va Soc Son se thay doi nhieu vS mirc xip hjng so voi cac huyen khac thugc
Su
1
2
3
4
5 Khu vuc thdm hut/
dulrif sinh thai Tham hut sinh thai rat cao
Tham hyt sinh thii cao Tham hyl sinh thdi trung binh
Tham hut sinh Ihdi
thap
Dytrii sinh thdi
Bdng 2. Gid trj thirdc do thdm hut sinh thdi vd cdc yiu td dnh hudng cua cdc qudn huyen thuoc thdnh phd Hd Ngi ndm 2009
Qudn, huyen
Hoan Kiem CSu Giay Ba Dinh Long Bien H^ Dong Hoai Due Tay Ho Thanh Xuan Hai B4 Tnmg Me Linh Dong Da Dan Phuong Thanh Tri Son TSy'*' Tir LiSm Hoang Mai Phiic Thp Qu6c Oai Gia L^m Dong Anh Thach T h a t ' ' ' Thudng Tin C h u o n g My*'' Thanh Oai My Dire Soc So"n''*
Gid tri thudc do (gha/ngudi)
7,115 2,519 2,449 2,138 2,116 2,083 1,605 1,173 1,039 0,845 0,731 0,695 0,684 0,588 0,546 0,495 0,359 0,313 0,141 0,124 0,022 0,015 -0,029 -0,037 -0,083 -0,088
Dien lich (lirr/)
5,3 12,0 9,3 59,9 48,3 82,5 24.0 9,1 10,1 142,5 10,0 77,4 62,9 113,5 75,6 40.3 117,2 147,0 114.7 182,1 184,6 127,4 232,4 123,9 231,5 306,5
Mdt do ddn so (nghin ngirdi/iim )
28,02 19,72 24,46 3.90 4,94 2,38 5.68 25,56 30,03 1,38 37,65 1.86 3,21 1,13 5,55 8,54 1,38 1.11 2,06 1,89 0,98 1,76 1,26 1,37 0,75 0,95
Ddt canh tac (ha)
15,3 56,9 3,3 1804,6 1327,9 4077,0 302,9 28,1 5,6 7560,6 6,4 3427,5 2637,0 3909.6 2908.3 872,7 6120,1 7317,3 6059,9 8932,0 6501,0 6553,3 13068,1 8292,2 9197,1 13536,6
Mat nirdc nuoi trdng thity sdn (ha)
0,0 6,7 2,0 94.7 34.8 111,1 575.7 33,9 8,5 354.6 18,4 208,5 849,7 166,3 184.0 441,0 341,1 272.0 183,0 553.0 209,3 730,1 583,2 338,2 674,3 278,6
Ddt rirng (ha)
0,0 0,0 0.0 0,0 0.0 0,0 0,0 0,0 0,0 3,1 0,0 0,0 0,0 778,3 0,0 0,0 0,0 1470.6 41,5 0,0 2457,1 0,0 303,8 0,0 3526,2 4760,6
!
oil
ilung (he)
S12.i
1126.1 905,11 3947.!
3411,1 3972.4 1393.0 836.2 993,0 5673^
970,i 3330,4
irmi
6134,1 4309,4 256y ASlli _53]M _487y _ 8 m 2
jrmi jgai __m>i
_3605J
j a ! UWOJil Hot nghj Khoa hoc Dia ly Todn qudc ldn thu 6. Thdnh phd Hui 9/201^
|iKj pja ly vlt T&i nguyen Moi truong Thira Thien Hue Hoi Pia ly Viet Nam
Cdc aiiltrfng thing ke
mSta
Phu Xuyen* ' U'ng Hoa BaVi Dd ldn mdu Bien (?d Tri lot thieu Tn ldi da Trt trun^ binh (fj) Dd Icch chudn (u) Phuang sai (if')
-0.127 -0,176 -0,301 29 7.417 -0.301 7.115 0.929 1.462 2.137
171,1 183,7 424,0 29 418.7 5.3 424 114.7 9S9 9.7 I&
1,07 0,99 0,59 29 17.06 0.59 37.65 7.59 I0.S4 117.64
9443,1 11786,0 16939,0 29 16935.7 3.3 16939.0 5265.1 4755,6 2.2.10"
756,2 1022.9 1090,1 29 1090.1 0.0 1 090.1
349.0 320,1 1.02.10'
0,0 0.0 10724.9 29 10724,9 0,0 10724.9 859,5 2263.5 5.1.1 If
6043.7 4765.6 6503.2 29 10395.0 512.6 10907.5 4397.8 2773.9 7.7.l(f gddC
sudung ddt
') Id cdc huyen dirge du bdo se thay ddi mirc xip hang thdm hut sinh thai Iheo phuang dn quy hogch thdnh phd Hd Ngi din nam 2020)
KET LUAN VA THAO LUAN
- Ket qua ciia nghien cuu nay da xac djnh dugc gia Iri Ihudc du tham hut sinh thai va dy tru sinh thai cho 29 qugn, huyen ciia Ha Ndi, tir do chi ra 3/4 sd lugng cac don vi lanh thd bj tham hut sinh thai, ddi hdi phai cd chien luge can bang giiJa nhu cau lieu thu va khai thac tai nguyen, nhat la tai nguyen dat.
- Trong bao cao quy hoach sir dung dat thanh phd Ha Noi den nam 2020, cac phuang an quy hogch dua ra chu yeu dua tren sd lieu hien trang va bien dgng sir dung dat eiing nhirng sd lieu eo ban dy bao ve phat trien kinh te xa hdi. Vdi uu the trong dinh lucmg mirc do tieu thu ciia dan cu dja phuang va kha nSng san xuat ciia dat dai, cac thudc do tham hut sinh thai va du tru sinh thai cd the dugc ung dung tot trong cong tac danh gia va dy bao phuc vy quy hoach su: dung dSt.
- Danh gia tham hut sinh thai va dy Irir sinh thai da duge thyc hien rat hieu qua d quy mo loan cau va qudc gia. La mgt trong cac qudc gia dugc id chuc Mgng ludi Dau chan Toan cau danh gia dua tren cac Ihudc do nay tir nam 1961 den 2007, Viet Nam ed dien bien thay ddi muc do tham hut sinh thai Iheo xu the chung ciia the gidi (5]. Kel qua nghien ciru dien hinh tgi thanh phd Ha Ngi cho thay, hudng nay cd the md rgng cho tSt ca cac tinh thanh khac trong lanh tho Viet Nam vdi dieu kien c^n dieu chinh mgt sd tham sd cua md hinh phii hgp vdi thyc tien danh gia d cap dia phuang. Trong khung canh bien ddi khi hau va canh bao loan cau hien nay, cac thudc do nay cung cd the dugc sir dung nhu la mgt ngudng danh gia ben vii'ng va la ea sd dua ra cac phuang an phdng tranh, thich irng vdi bien doi khi hgu d cap dia phuong,
TAI LIEU THAM KHAO
1. So Tai nguyen va Mdi Irudng thanh phd Ha Ndi (2011). Quy hogch sir dung ddt din nam 2020 vd ki hoach sir dung ddt 5 ndm (2011-2015). Ha Ndi.
2. Tdng cyc th6ng ke (2010). Nien gidm thdng ke thdnh phd Hd Ngi. NXB Thdng ke. Ha Ngi 3. Cornish A, (WWF lead author) (2011). Hong Kong Ecological Footprint Report 2010 Paths to a
Sustainable Future. Hong Kong.
4. Ewing B., D. Moore, S. Goldfinger, A. Oursler, A Reed, M. Wackernagel (2010). Ecological Footprint Atlas 2010. Global Footprint Network.
5. Kilzes J,, A. Galli, S. Rizk, A. Reed, M. Wackernagel (2008). Guidebook to the nalional footprint accounts 2008. Oakland: Global Footprint Network.
0)A LY TUNHIEN, TAI NGUYEN THIEN NHIEN vA MOI TRUQNG
Hpi Dja ly va Tai ngu>cn Moi Iruong ThiJa Thien Hud Moi Dja ly VictN,
6. Lin L., X. Gaodi, C Shuyan, L. Zhihai, S. Humphrey, C, Shcngkui, G. Liqiang, L. Haiylnii Ewing (2010). China Ecological Footprint Diocapacily, Cities and Development Report 20j Oakland: Global !"oolprinl Network.
7. Rees W., M. Wackcnagel (1996), Urban ecological footprints: why cities cannot be sustaiihibk and why they arc a key to sustainabilily. The Environmenlal Impact Assess Review, Vol. Ifi p 223-248.
8. Stokar T., M. Steinemann, B, RiJegge, J. Schmill (2006). Switzerland's ecological footprint. Oflii federal de la slalisiique (OFS) Neuchalel,
9. WWF Japan, Global Footprint Network (2009). Ecological Footprint Report Japan 2009. Japan.