Nghien cffu - Trao doi
^Dif bao anh hirifng cua bien tfdi khi hau den dienjich, nang suat cay lua cac xa
ven bien huyen Hau Loc va [\lga Sofn, tinh Thanh Hba giai doan 2016-2020
O ThS. TRAN TH| THANH HUYEN, ThS. NGUYEN TH| HANG, ThS. NGUYEN VAN VINH Tmdng Cao ding Tii nguygn vi Mgi trudng miSn Tmng
B
ign dgi khi hpu tic dgng dgn nhieu finh vt/c kinh tg trcng dd cd Hnh vuc ndng nghigp vi sin xugt lUdng thuc. Do dd, vigc di/dodn ning suit ciy trdng, cp theli ciy Ida, trong digu kign BDKH trong tuang lai li rit quan trpng. Bii viet niy gidi thigu kgt qui nghiin ctlu budc diu khi xem xit cic Idc dgng cua si/ tdng nhigt dg, they dgi luipng mua vd ting su xim nhgp m$n dgn ning suit, dign tich trdng lud tpi cic xi ven biSn huygn Nga San vi Hgu Lgc tlnh Thanh Hda glal dopn 2016-2020. Kgt qui nghiin ciiu cho thay, dgi vdi kich ban B2 ning suit lua vp hg thu vi thu ddng tdng lin lupt li 13% vi 14%, dign tich trdng Ida dubio quy hopch din nim 2020 deu giim tU3% den 33% so vdi dign Uch trgng nim 2015.B$t v£n dS
6 hsiu het c^c nadc dang phkt triln, sU phkt tnen cua n^n kinh t§' qufic dan dUa chD y§'u vko n6ng nghigp. Anh hudng cua hi$n tUdng tiki dSt n6ng ISn tdi skn xukt n6ng nghi§p se de dga tdi si,!
phit triln cCia nSn KT-XH cCia qu6c gia. Nen ndng nghiep phg thudc r^t nhilu vao tki nguydn nudc va dilu kidn khi hku. Tai cac qudc gia mk ky thu4t gi4m nh?
han hkn vk ID lyt cdn han c h l , ckc nhkn td vat ly chfnh knh hudng tdi si) skn xult ndng nghiep (dat dai dia hlnh, thdi tilt) ft phu hpp cho vide canh tac, d i n d i n nang sud't cdy trdng se cue ky nhay ckm vdi sU biln doi ciia
khf hau. Bai bao nay gidi thidu kit quk nghien cilu budc diu v l danh gia tac ddng cCia BDKH, cu t h i la sy tang nhidt dd va thay d l i lupng mua, sy gia tang xdm nhap man d i n nSng suit va dldn tfch d i t canh tac cdy lija cua cac xa ven biln Hau LOc va Nga Sdn, tfnh Thanh Hda.
Gidi thl$u ve khu v^c nghien cijru
Hau Ldc la huydn ddng bSng ven biln, cich TP. Thanh Hod 25 km ve phia Ddng Bac vdi t i n g didn tich ty nhidn la 14.367,19 ha.
La mdt huydn ddng bSng ven biln, Hdu Ldc cd dja hlnh thlp dan tCr Tdy B i c xudng Ddng Nam. Vung ven biln bao gdm
cac xa Lidn L$c, Quang LOc, Hoa L<ic, Phu L<ic, Hod LJc, HSi LOc IVIinh LSc Hung L|c, Da L$o, Ngu LOc cd di^n tfch la 5.610,07 ha.
chllm 38,29% di0n tich toin huydn. Ddy Id viing dSt dupc hlnh thanh do qua trlnh bdi d i p cOa sdng vd biln tU xa xUa, cd dia hlnh tuong ddi bing ph&ng, thanh phin CO gidi chu y i u Id cat pha, d l thoat nudc, thich hpp cho vi^c trdng cdy mau va cdy cdng nghjdp n g i n ngdy nhu lac, d$u, ngd. Ddy cDng Id vung cd cdc cila sdng, cUa biln ndn sd t|lp trung phdt triln thuy hdi s i n cua huy^n.
Nga Son n i m v l phia Ddng Bdc tlnh Thanh Hoa. thuOc vung ddng b i n g ven b i l n cua tlnh.
106 Toi nguyen vd M6i tryong | K»l-TlrtimigOU
Trung tdm huy$n Id thj trin Nga Sdn, each TP. Thanh Hda khodng 40 km v l phia Bdng Blie, cdch thi xa Bfm Sdn khodng 10 km v l phia Ddng Nam va each thj trin Kim Sdn (Ninh Binh) 17 km v l phfa Nam. Nga Sdn cd 3 tilu viing, trong dd tieu vung vung biln bao g6m cac xd: Nga Diln, Nga Phu, Nga Thdi, Nga LiSn, Nga Thanh, Nga T i l n , Nga Tdn vd Nga Thijy, didn tfch 619,97 ha, chilm 39,16 % didn tich tU nhien todn huyen. La vung dat dUdc hlnh thanh do qud trinh bdi ddp, lin biln. Ddy Id vung chuydn canh cdi cd ndng suat va ehlt lUdng cao.
DU bao xu th^ bien dSi khi h|iu trdn dja ban Nga Sdn vd H$u L$c giai do^n 2016-2020
Xu thi tfiay dil nhipt dp Theo kich bdn BDKH 2012 vdi mUe phat thdi trung binh B2, vdo ndm 2020 nhi^t dd trung blnh ndm trdn dja ban tfnh Thanh Hda tdng 0,5°C so vdi trung binh giai dogn 1980-1999. Trong eac mua trong ndm, mUe tdng nhiet dd cd phdn khde nhau. Nhi^t dd trung binh tu thdng VI d i n thang VIII tdng 0,4"^, cde thdng cdn Igi trung binh tdng 0,5°C. D l i vdi nhiet dd cue trj, sU tdng Idn cija nhi^t d$ tdi eao vd nhidt dd t l i tfilp khdng gidng nhau. Vdo giOa Thi ky 21. nhiet dO tdi thlp taing binh mua ddng tdng tU 1°C d i n 1,2°C, nhi$t dO t l i cao trung binh tdng tu 1,2°C d i n 1 .S^^). Vdo mua hd. mUc tdng nhi^t dd t6i eao Id tu 1.2'^ d i n 1,5°C. nhidt dO tdi thlp tdng tU 1,5°C d i n 1.7°C. Xdt trung binh cd ndm. nhiet dd tdi thlp trung binh tdng tU 1.2°C d i n 1 .Si^;, nhidt dd tdi cao trung binh tdng tU1.5°C d i n 1.7fC.
NhU vdy. theo kich bdn ndy mua hd trdn dia bdn tlnh Thanh
Hoa ndi chung. Hau Ldc vd Nga Sdn ndi ndng se keo ddi, mua ddng va xudn se thu h^p lai. Nen nhiet se tdng cao, dde bidt se ed nhOng dilm ndng cao tuydt d l i mdi xuat hidn vdo mua he, ndng ndng se ngay cang gay gdt hdn, keo dai hdn. Mua ddng trd nen I m hdn.
Xu thi biin doi lifpng mud Theo kjch ban BDKH (2012), vdi mUc phdt thdi trung binh 82, mUc tdng lU0ng mUa ndm trdn dia ban tfnh Thanh Hda vdo nam 2020 Id 1,1°- so vdi lupng mUa nam trung binh giai dogn 1980 - 1999. SU tdng gidm lUdng mUa trong cac mua khde nhau trong nam cung khde nhau. Theo dd, vdo mua ddng (thdng Xll-ll) lU0ng mUa cd xu hudng tdng so vdi trung binh nhilu nam giai dogn 1980-1999. Trdn dja ban tinh Thanh Hda, IUOng mUa mua ddng tdng vdo ndm 2030 Id 1,0%.
Vdo mua he, lU0ng mua tang 3,4%, mua thu Id 1,3%. Trong khi dd vdo mua xudn (thdng lll-V), lUdng mUa ed xu hudng gidm, vdi lupng gidm Udc tinh Id 1,4%.
LUdng mua tdng len vao nhOng thdng mua he dU bdo vung ven biln Hdu Ldc, Nga Sdn se tdng nguy cd ngdp ung 6 vung trung gdy khd khdn cho trlng trot vd nudi trdng thuy sdn.
Xu thi xim nhpp mpn Vung ven bien Hdu Ldc vd Nga Sdn cd cdc cua sdng Len, sdng Can, sdng Bdo Vdn, sU xdm nhdp mdn chD yeu do thuy trieu vd tneu cUdng. Ngodi ra cdn do tdc ddng cua gid mua Ddng B^e thii vdo nhOng thang mua ddng k i t hdp vdi trieu cudng mgnh. Kit qud quan trie do mdn trdn sdng Ldn tgi trgm Cu Thdn, cdch ciSa sdng 19 km dp mdn thlp nhat do
dupc giai dogn 2005-2015 ia 0,3%o. DO mdn cao nhdt ghi dupc tgi trgm Cu Thdn Id 7,1%o vdo ndm 2010. Tgi trgm Lgeh Sung cdch cisa sdng 2 km, dd mdn cao nhat do dupc ndm 2015 Id 18,1%o. Dd mdn 1%o cd dd xdm nhap sdu nhit Id 17 km trdn sdng Len do dupc vdo ndm 2009.
Theo bai bdo "Ngidn cUu, ddnh gia tdc ddng eua biln d l i ddng chdy kidt d i n xam nh^p mdn hg du sdng Md va sdng Cd" ciJa tac gid LUdng Ngpc Chung, vien khoa hoc Thijy Lpi, dU bao dd xam nhdp mdn cd dd sdu khac nhau tren he thing sdng Len vd song Bdo Van vdo ndm 2020. Trdn sdng Len, ranh gidi mdn 1%o xam nhap sdu 20km, 4%o xam nhdp sdu 18,5km, do man 30%o xdm nhdp sdu vdo 3,5km. Trdn sdng Bao Vdn, dd m^n dao ddng tU 1 %o den 15%o. Tgi vj trf edeh nga ba sdng 2km, dd mdn Id 15%o.
Theo bdi bdo 'Md phdng mdn theo cac kjch bdn BDKH, nudc biln dang trdn hd thing sdng Ma tlnh Thanh Hda cua Bdo Thgnh vd nhdm nghiSn cUu Phdn vi$n KTTV&MT phia Nam. trSn sdng Len vdi dd mdn 4%o, khodng cdch xdm nh^p sdu nhit vdo ndm 2020 la 24,2 km (Ung vdi mUc B2 cua kich bdn BDKH 2012).
DU bdo xu t h i biln d6\ dipn tfch trdng vd ndng suit cdy lua trdn dja bdn cdc xa ven biln H|u L ^ va Nga Sdn, Thanh H6a
Anh hudng cua nhiit dp, lupng mua din ndng suit, sin lupng dy Itfa
Theo bdi bdo " K i t qud bUdc ddu v l du bdo ndng sudt lua dudi tdc ddng cCia BDKH tai hd thing tudi phia nam sdng Ma" cua tdc gid LS PhUdng Ddng vd cOng sU.
ndng suit edy tua dupc dU bdo Tai nguyen vo Mdi trudng | KM-Tiling 11/2016 ^Qy
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cho giai doan 2013-2041 vdi kjch b i n BDKH B2 (chl xdt tdi sy tdng nhidt dd, gia tSng lupng mua va gia tang mile phat thai CO2) trdn phin m i m AquaCrop nhu sau:
Nang suit cdy lua thyc t l nam 2013 tai Nga Son va Hdu Ldc vu hd-thu la 3,625 tIn/ha; vy thu-ddng Id 4,071 tSn/ha
Nang suit dy bao: Vy he- thu la 3,865 tSn/ha; vy thu-ddng Id 4,180 tIn/ha.
Cd t h i thiy, ddi vdi vung nghidn cUu, neu ch? xdt cdc tdc d^ng cua sy tang nhiet do, sy thay d l i lupng mua vd tang ndng dO CO2 theo kich b i n B2 thi BDKH cd t h i khdng de dpa d i n sy s i n xult lua. Ndng suit nhin Chung v l n tang nhilu so vdi giai doan trudc dd.
Nhan thiy k i t q u i trdn ngupc vdi nhdn dinh ciJa IPCC. Ollu niy cd t h i gill thich nhu sau:
V l CO b i n , sy tdng g i p ddi ndng dd CO2 cd t h i ldm tSng qud trlnh quang hpp tU 30 d i n 100%, tuy thulc vao cac dilu ki^n mdi toldng khde nhu nhi^t dd va dO Im.
Tang ning dO CO2 iam gia tang nang suit tilm ndng cua lija, nhung tdc ddng tidu cyc Cila sy tdng nhi$t d | Idn hdn tac d$ng tfch cyc cCia sy tang ning dd CO2.
TSng nhidt dd vd tSng lupng mua ldm cho sdu bp vk cdn trung smh s i n nhanh hdn, mUc dd tdn phd mua mdng nhilu hpn, tuy nhidn phin m i m AquaCrop dung trong bai bdo khdng t h i m l phdng v l n d l nay.
Anh hudng ciia bign dgi khi hgu vi xim nhgp mgn dgn dign tich trdng lua vio nim 2020
Nhidt d l gia tdng lam cho sy phat t n i n ciJa cdy trlng cd t h i
thay d l i , d i n d i n thdi vy cay trlng bi thay d l i . Dieu nay ddi hdi p h l i thay d l i ky thuat canh t4c cung nhu cdc lal gilng c i y trlng phu hpp hPn. Hidn tupng I m b i t thudng 6 d i u vy Xudn iam cho ma va cay lua mdi c i y sinh trudng nhanh, nhilu noi khdng c i y kip ndn ma bi gia, p h l i huy de gieo lai. Sau khi cay, lua Xudn sinh trudng q u i nhanh, nhiing ndi khdng kip thdi dilu chfnh quy trlnh tham canh thi ddng nhd, bdng nhd, it hat, vi vdy ndng suit lua giim ro r$t (giim trdn 10% so vdi nhOng ndm binh thudng).
xam nh^p mdn gia tang iam giim nang suit cdy trlng. D | man trong nUdc vd d i t tdng iam glim q u i trlnh sinh trudng cDa c i y lua, d i n d i n nang suit thlp, n i u do man cao gap thdi ky lua t r i bdng thi g i n nhu m i t trlng. Trong thdi gian qua, xdm nhap m$n gdy thi^t hai ldn cho boat d|ng trlng lua tai cac xa ven biln H$u L|c vd Nga Son.
Tlnh hlnh xdm nh$p m$n iam cho hidu q u i s i n xult thlp, hing tram hecta lua, hoa mau bi thi^t hai do man.
Trudc xu t h i nang xult cdy lua cd t h i giim 10% khi nhi$t dd tdng Idn 1°C, sy xdm nh^p mdn gia tdng gdy mSt di§n tich d i t trlng lua, mdt s l xa ven biln Hdu L|c vd Nga Son da cd dy bdo quy hoach v l di^n tfch trlng lua vao nam 2020 nhu sau: Xa Da Ldc didn tich trlng lua vdo nam 2015 la 259,07 ha, d i n nam 2020 la 250,67 ha, giim 3,3%. Xa H l l Ldc di^n tich trlng lua nam 2015 la 29,99 ha, d i n nam 2020 Id 27,94 ha, giim 7,8%. Xa Nga Phu dl^n tich trlng lua vao nam 2015 la 650 ha, d i n nam 2020 la 570 ha, gilm 12,3%. Xa Nga Tiln didn tfch trlng lua vao nam 2015
I I 113,94 ha, d i n nam 2020 11 76,21ha. g l i m 33,1%- X I Hung L|c dldn tich trlng lua v i o nim 201511203,60 ha, d i n n i m 2020 14 187,03ha, g i l m 8 , 1 % .
K^t l u | n
Bdi b i o nay da gidi thidu kit q u i nghidn cUu bUdc d i u khi xem xdt cdc tdc ddng ciJa sy tdng nhidt d | , thay d l i lupng mua vk sy x i m nh^p m j n tdng cao din dien tfch trlng v l nang suit lua tai cac xa ven biln huy0n Nga Son va Hku Lpe, Thanh Hda. Kit q u i cho thiy dd'i vdi kich bin B2 nang suit lua vy thu-ddng v l hd- thu tdng l i n lupt 11 19% v l 14%
v i o ndm 2020. Dudi tac d$ng cilia BDKH va x i m nhip m$n gia ting da phin c i c xa ven biln diu c6 quy hoaeh gilm di^n tfch trlng lua nam 2020 til 3%-33% so vdi di^n tfch trlng nam 2015.
T i l ll^u tham k h i o 1. LUdng Ngpc Chung, 2016.
Ngiin cilu, dinh gid tde dgng dia bign ddi ddng chiy kigt dgn xim nhgp min hp du sdng Md vd sdng Ci. 55 nam vi$n quy hoach Thuy Ipi 1961-2016, trang 136-149.
2. Ld PhUPng D i n g , DUdng Thanh N i l , 2012. Kgt qud budc diu vg du bio ndng suit liia dudi tic dgng cua BDKH tpi hg thgng tudi phia nam sdng Ma. Tpp chl khoa hpc ky thuit thijy Ipi v l mdi trudng, s l 39, trang 21-28.
3. B i o Thanh, Vu Thi Huong, Ngd Nam Thinh, Pham Thanh Long, (2015). Mi phdng mdn theo cdc kich bin BDKH, nude bign ddng trin hg thgng sdng Mi tlnh Thanh Hda. Tap chf t l i nguyin v l mdi trudng, 2015, s l 2.
4. B | Tdi nguydn vd Mdi trudng, (2012). Kich bdn BDKH vd nudc bign ding cho Vigt
1 0 8 Tdi nguydn vd M61 truong | Kt 1 • ntn 11/M16
