Đặc điểm phân bố vi sinh vật và ảnh hưởng chế phẩm vi sinh Lypomycin M đến khả năng giữ nước vùng bán khô hạn tỉnh Ninh Thuận

DAI HOC
QUOC
GIA
HA
NOI
TRirdNG
DAI HOC KHOA HOC
TIT
NHIEN
• ^
5i^
^ ^
H^
• •
H^
DAC DIEM PHAN BO VI
SINH
VAT VA ANH
HITONG
CHE
PHAM VI SINH LYPOMYCIN M
DEN KHA NANG
GI0 Nl/OC
YUNG
BAN KHO
HAN
TINH NINH THUAN
MA
SO:
QT-06-41
CHli TRI

DE
TAI:
ThS.
TRAN THI
TUYET THU.
CAC
CAN
BO THAM
(ilA:
TS. BUI THI
NGOC
DUNG
ThS.
NGUY£N
KIEU
BANG TAM
CN.
NGL
YIIX
XUAN
HLA.N
HA NOI - 2007
^-jf-
H'^-C
Q'J'^C
^1/-
-A :\r ;
&L/
^il
BAO CAO TOM TAT

1.
Ten de tai:
"Dqc
diem phdn bo vi sink vat vd dnh Huang che phdm vi sink
Lypomycin M den khd ndng
gin nu&c
rung bdn khd
hqn
tinh Ninh
Thuqn'\
Masddetai:QT-06-41
2.
Chii tri
de tai: ThS. Tran
Thj
Tuyet Thu
3.
Cac can bo tham gia
thirc
hien:
TS.
Biii
Thi Ngoc Dung - Vien Quy hoach va Thiet ke Nong nghiep;
ThS.
Nguyen Kieu Bang Tarn - Khoa Moi
truang,
Truang
DHKHTN;
CN. Nguyen Xuan Huan
-

Khoa Moi truang,
Trucrng
DHKHTN.
4.
Muc tieu va noi dung nghien
ciru
4J,
Muc tieu nghien
ctiu
Hien tugng sa mac
hoa,
hoang mac boa
a tinh
Ninh Thuan da va dang tra
thanh mot trong
nhirng
van de can dugc cac nha khoa hoc, nha quan
ly
quan tam
giai quyet. Mot trong nhung yeu to can tra rat
Ian
den qua
trinh
canh tac nong
nghiep a vung nay la
nuac
tuai.
Do dieu kien
khi
hau kho

han,
kha nang giu nuac
cLia
dat kem nhung kha nang
bdc
hai nuac
lai
de dang, lam anh huang khong nho
den qua
trinh
canh tac cay trong va khu he sinh vat dat tai day.
Vi
vay,
viec nghien
cuu dac diem vi sinh vat va anh huang che pham vi sinh Lypomycin M den kha
nang
giiJ
nuac vung ban kho han
tinh
Ninh Thuan
nh^m
muc
dich
cai thien dac
tinh
dat theo huang c6
Igi
cho muc
dich
su dung la can thiet.

42.
Nqi
dung nghien
cini
- Hien trang
sir
dung dat
tinh
Ninh Thuan: dat do vung ban kho han, dat xam nau
vung ban kho han va dat man kiem.
- Cac
tinh
chat ly - hoa - sinh hoc cua dat.
- Ket qua
thi
nghiem ve kha nang giu am
ciia
dat
5. Cac ket qua dat duoc
1.
De
tai da xac dinh dugc nhom dat do, xam nau va dat man kiem
vijng
ban kho han
Ninh Thuan c6 thanh phan ca giai nhe den trung
hlnh.
chu yeu la dat cat pha
thit,
ihil
pha cat va pha set. Phan ung cua dat

a
muc rat chua. chua vu'a den trung
tinh
tai cac
phAu
dien dat khac nhau
ti;iy thupc
vao dieu kien canh tac. Do bao hoa baza
cao.
dung
tich
hap phu va
irao
doi cation cua dat cao. Ham
krano
chat huu
co
va
cac yeu to dinh
duang
da
lugng
N,
P,
K
can
thiet cho cay trong chi dat
a
muc
ngheo den trung

binh.
2.
Tinh
trang thieu
nude
va ham lugng cac chat dinh duang ngheo nan la mot trong
nhung tac nhan han che qua
trinh
san xuat nong nghiep tai viing nay.
3.
Su phan bd cac quan the vi sinh vat khac nhau d
tii'ng loai
dat va cac dieu kien
canh tac. Quan the sd lugng vi khuan chiem chu yeu, nhung thap han nhieu so vdi
cac dat canh tac thong thudng cd dieu kien
am
va ham lugng cac chat dinh duang
cao han. Quan the xa khuan, nam mdc, nam men chi nhieu ve sd lugng nhung
khong da dang ve thanh phan loai. Dac biet,
sir
cd mat cua cac loai nam men d cac
dat trdng cay khac nhau la khac nhau.
4.
Ket qua
thir
nghiem kha nang giu am
ciia
dat cho thay nhirng phan
ling
khac nhau

d dat trdng cay dau tuang d
16
thi
nghiem va 16 ddi
chiing.
Cac cay d
lo
thi
nghiem
cd la xanh han, than cay map han so vdi ddi
chiing.
6.
Tinh
hinh
kinh
phi
ciia
de tai
De tai dugc hoan thanh nhd su giup da, tao dieu kien
ciia
Ban chu nhiem Khoa
Moi tru'dng, Phong Khoa hoc C6ng nghe tru'dng Dai hoc Khoa hoc Tu nhien va ngudn
kinh
phi
hd trg cua Dai hoc Qudc gia Ha Noi.
Kinh
phi
dugc
c^p:
15. 000.000

ddng
BAN CHU NHIEM KHOA MOI
TRUONG
r^^^
^^^
a.
CHU TRI DE
TAI
ThS.TrlnThiTuydtThu
CO QUAN CHU TRI DE TAI
G
O-'
'6/
'/
j'
.;'
t'
DAI Hen
'KHOA
H,'jf_
/
\- >
y
7/
Summary report
1.
Title:
''
Distributive characteristics of microorganisms and effect of Lypomycin M
microbial production on water-retaining capacity of middle arid area in Ninh Thuan

province".
Code:
QT-06-41
2.
Head of project: Msc. Tran Thi Tuyet Thu
3.
Participants:
Dr. Bui Thi Ngoc Dung - National institute of agricultural planning and
projection.
Msc.
Nguyen Kieu Bang Tam - Faculty of Environmental Sciences.
Base.
Nguyen Xuan Huan - Faculty of Environmental Sciences.
4.
Research purpose and content
4.1.
Purpose of Research
The aims of this research included research on distributive characteristics of
microorganisms and effect of Lypomycin M microbial production on water-retaining
capacity of middle arid area in Ninh Thuan province in order to improve soil
characteristics for using in agriculture.
4.2.
Contents of Research
For achieving the purposes above, in this study was conducting the following
contents:
- The status of agricultural land use in Ninh Thuan province.
- Biologico - Chemico - Physical Properties of Soils.
- Carry out experiment on water-retaining capacity
5.
Results of study

- Biologico - Chemico - Physical Properties of Soils were analized:
pH^.Q.
PHKCI-
0M%,
N%,
P%,
K
%,
CEC,
total Microorganisms. Studying soils are low fertility, acid
reaction
- Water
deficiency
and low content of nutrional elements in soils are main limited
factors in agricultural production in this area
- Lypomycin M microbial production allows plant grow
stronger
and
develop
better than control due to improvement of water retained capacity of soils in middle arid
area
MUC
LUC
Trang
1
CHUDNG
1.
TONG QUAN
TAI
LIEU

1.1. Dieu kien
tu
nhien
va
kinh
te xa hoi
tinh
Ninh Thuan
1
1.1.1. Di6u kien
tu
nhien
tinh
Ninh Thuan
1
1.1.2.
Tinh
hinh kinh
te xa hoi
tinh Ninh Thuan
4
1.2.
Hien trang
va
tiem nang
su
dung
tai
nguyen
dat

tinh Ninh Thuan
5
1.2.1.
Hien trang
su
dung
dat 5
1.2.2.
Tiem nang
sii
dung
dat
nong nghiep
8
1.3.
Hieu
qua
kinh
te
sir
dung
dat 8
1.4.
Khai quat
ve vi
sinh
vat
sinh mang nhay
9
1.4.1.

Dinh nghia
9
1.4.2.
Chiie
nang
cua vi
sinh
vat
sinh mang nhay
10
1.4.3.
Tac
dung
cai tao dat
ciia
che
pham Lypomycin
M
10
CHUONG
2. DOI
TUGNG
VA
PHUDNG
PHAP NGHIEN
CUU 12
2.1.
Ddi
tugng,
dja

diem nghien
cuu
12
2.2.
Phuang phap nghien euru
12
2.2.1.
Phuang phap
bd tri thi
nghiem ehau
vai
12
2.2.2. Phuang phap nghien euru trong phong
thi
nghiem
12
CHUDNG
3. KET QUA
NGHIEN
CUU VA
THAO
LUAN 14
3.1.
Mot sd dac
diem
ly hoa hoc
ciia
cac
nhom
dat

nghien
cuu
14
3.1.1.
Nhom
dat do
viing
ban kho han
14
3.1.2.
Nhom
dat xam nau
viing
ban kho han
16
3.1.3.
Nhom da't
man 23
3.2. Dac diem phan bd vi sinh vat 23
3.2.1.
Sir
phan bd cua quan thi vi khuan 24
3.2.2. Su phan bd cua quan the xa khuan 25
3.2.3.
Su phan bd cua quan the nam mdc 26
3.2.4. Su phan bd ciia quan the nam men 27
3.3.
Anh
hudng eiia
che pham lypomycin M den kha nang giu nude

ciia
dat 28
KET LUAN VA KIEN
NGHI
30
TAI
LIEU THAM KHAO
31
PHU LUC 32
DANH MUC BANG VA HINH
MINH
HOA
DANH MUC BANG
Phu
luc
1:
Cac tinh chat ly hoa hoc ca ban cua dat Ninh Thuan
Phu
lue
2: Ket qua xac dinh vi sinh vat tong sd trong dat d Ninh Thuan
Phu lue 3: Thang danh gia cac tinh chat ly hoa hge ca ban cua dat nghien cuu
DANH MUC HINH MINH HOA
Trang
Hinh
1.
Do chua cua dat dd d My San, Ninh San, Ninh Thuan
14
Hinh 2. Ham lugng chat huu ca, N, P, K tong sd cua dat dd d My San,
15
Ninh San, Ninh Thuan

Hinh 3. Do chua
ciia
dat xam nau
viang
ban kho han Lam San, Ninh 17
Son, Ninh Thuan
Hinh 4. Do chua
ciia
dat xam nau
viing
ban kho han Quang San, Ninh
18
San, Ninh Thuan
Hinh 5. Do chua ciia dat xam nau vung ban kho han huyen Ninh Phude
19
Hinh 6. Ham lugng chat huu ca, N, P, K tong sd trong dat xam nau 20
vdng
ban kho han Lam San, Ninh San, Ninh Thuan
Hinh 7. Ham lugng chat huu ca, N, P, K tong sd trong dat xam nau
21
viing ban kho han Quang San, Ninh San, Ninh Thuan
Hinh 8. Ham lugng chat huu ca, N, P, K tong sd trong dat xam nau 22
viing
ban kho han Ninh Phude, Ninh Thuan
Hinh 9. Sd lugng vi khuan trong cac nhom dat nghien
eiru
24
Hinh 10. Sd lugng xa khuan trong cac nhdm dat nghien
ciru
25

Hinh
11.
Sd lugng nam mdc trong cac nhdm dat nghien cuu 26
Hinh
16.
Sd lugng nam men trong cac dat nghien cuu 27
MO
DAU
Thieu nude, han han la mot trong nhung nguyen nhan ca ban din den
hoang mac hoa ddi vdi nhieu viang dat tren the gidi. Theo thong ke cua
FAO_UNESCO,
tai nguyen dat the gidi hang nam cd khoang
tir
5 - 7 trieu ha bi
ma't
kha nang san xuat do thoai hoa, kho han. Han ban da lam giam nang suat
miia mang, nhieu nai mat trang va gay nen nan ddi cho hang tram trieu ngudi d
Chau Phi, viing Trung can Dong. Hoang mac hoa da
Ian
rgng den ca nhirng
viing nhiet ddi am nhu d Viet Nam. Do vay, nghien cuu cac tinh chat ly - hda -
sinh hoc dat, bao ve ngudn nude,
giir
am dat va cung cap nude cho trdng trot da
va dang la nhiem vu cap bach ddi vdi moi qudc gia tren the gidi.
Viing
cd nguy ca han han cao dugc quan tam d nude ta la tinh Ninh
Thuan. Day la dia phuang cd
khf
hau kho han nhat cua ca nude. Viec dam bao

ngudn nude tudi cho san xuat nong nghiep
luon
la van de cap thiet, nhat la trong
thdi gian ban keo dai. Hien nay da cd nhieu mo hinh canh tac tiet kiem nude
dugc ap dung
ciang
vdi mot sd chat giu am hda hge cd kha nang giu nude trong
dat tai mot sd dia phuang trong tinh. Tuy nhien, hieu qua mang lai chua cao.
Trong giai doan hien nay, yeu eau dat ra ddi vdi cac san pham chat
gifi
am khong chi la kha nang
giO
nude trong dat ma eon phai dap ung dugc yeu eau
ve duy tri can bang he sinh thai dat. Viec tim hieu nghien euru cac dac diem sinh
hoc dat ket hgp vdi viec su dung cac san pham sinh hge da dugc nghien cuu ung
dung la rat can thiet ddi vdi
viing
dat kho han nhu d Ninh Thuan. Vi vay, de tai:
""Dac
diem phdn bo vi sinh vat vd dnh huang che phdm vi sinh Lypomycin M
den khd ndng giir
nu&c
viing bdn kho
hqn
tinh Ninh
Thuan''
dugc dat ra
nham tim hieu ve dac diem phan bd cua vi sinh vat trong mot sd loai dat chinh
va anh hudng
ciia

che pham den kha nang giu nude trong dat.
CHUONG 1. TONG QUAN TAI LIEU
1.1. Dieu kien
tir
nhien va kinh te xa hoi
tinh
Ninh Thuan
LAAdt UUNCi
fSI^VllM.
L-ap***
t:^':' TrcLU»
^
;|lr||-
Mil Luiria
Ill
.
r'
irtprr
., ,.^^^.
'.'

Ifc^,. ifc-
:
i;
Krr
i
—J
1 "~
r
1

1
J
(
.1
1
i'
\
1
.1
1 ^-
r
1
i'
1
L.
1
1
1
1
1
.1
•^^
1
/
1
„
••
-
+
/ / NINH

PHUO:-
1
L.
~"— -•*' 1
•|
1
1
1
9IMH 1
TKlfAN '"*
1
1
K
9
[
_-, /
1
t
^ * ~ — "i
KrIAHh
HOA
'"-—.
_
J
,'
-!• Nl^J^-1
i-iAi
1
.
*— ^

J—J
1
r
', *
_jr^
l-t.i 7^
i:ir.
1
1
t
••
1
)
}
I
i
1
1
1
L_-,
'
7.7.7.
Dieu kien
tu nhien
tinh
Ninh Thuan
al
Vi tri dia ly - dia hinh
Ninh Thuan la tinh cue Nam Trung Eg, d vi tri dia ly
iri8'14"

den
ir09'15"
vT
do Bae va tu
108W08"
den
109^1475"
kinh Dong. Phia
Bk
giap
tinh Khanh Hoa,
phia
Nam giap tinh Binh Thuan, phia Tay giap tinh Lam Dong,
Phia dong cd bd bien dai 105km. Nam d vi tri trgng diem giao thong doe qudc
16 1 A, dudng sat Bac - Nam, qudc
Ig
27
len
Tay Nguyen.
Ninh Thuan dugc bao bgc bdi ba mat
niii
va mot mat bien. Phia tay la
viing niii
eao giap vdi Da Lat,
phia
bac va
phia
nam cd hai day nui cao
Ian
ra sat

biin.
Cd ba dang dia hinh chinh la mien
niii,
ddng bang,
viing
ven bien. Dia
hinh tuang ddi doc va ed hudng thap dan tit tay sang dong va
tir
tay bac xudng
dong nam. Viing nui cao chiem 63,2% tong dien tich tu nhien toan tinh, viing
go ddi chiem 14,4% va ddng bang la 22,4%.
Toan tinh ed 8 dinh nui cao
tix
1000 m trd len so vdi mat nude bien, trong
dd huyen Ninh San cd cac
niii
Phude Binh (1926m), Bonnonh (1652m), Marai
(1637m), Chaidion (1542m), Lang Ma Bio (1282m); huyen Ninh Hai ed
niii
Hao Chu Hy (1451m),
niii ehiia
(1040m).
bl
Dieu kien khi
hau,
thiiy
van
Nam trong vanh dai khi hau nhiet ddi am, tuy nhien khi hau Ninh Thuan
lai ed nhung net rat dac biet, dugc xep vao che do nhiet ddi dien hinh vdi cac
dac trung: ed nen nhiet do eao

deu
quanh nam, lugng mua nhd, lugng bdc hai
Idn
i\i
1.670 - 1.827 mm, gid nhieu, am do khong khi thap, khong cd mua dong
va suang
mudi.
Vi vay, Ninh Thuan dugc xem la viing kho ban nhat ca nude.
Nhiet do trung binh
27^C,
ed hai miia ro ret, miia mua
\\i
thang 5 den
thang
11,
miia kho
xvi
thang 12 den thang 4 nam sau. Lugng mua trung binh 705
mm va tang dan theo do cao tren 1.100 mm d viing mien
niii.
Do am khong khi
tir
71
-
75%. Nang lugng
biie
xa
Idn,
tong tich on 9.500 -
lO.OOO^C.

Nhirng ket
qua nay cho thay Ninh Thuan la khu vue ed miia kho keo dai va khac nghiet,
trong vdng 8 thang,
tir
thang 1 den thang 8, lugng mua trung binh chi dat 270
mm bang lugng mua trung binh mot thang trong miia mua cua phan
Idn
cac khu
vue khac d nude ta.
Dieu kien khi hau kho ban da gay khong it khd khan cho san xuat nong
nghiep, anh hudng den
sir
phat trien
ciia
dat, gay ra tinh trang man hda, kiem
hda va
chai
cung dat be mat.
Luu
virc
cac song chinh cd
tdng
chieu dai 430km,
gdm
2 he thdng song
chinh:
-
He thdng song cai dai 105 km va cac song nhanh bao gdm: song Me Lam,
song Sat, song 6ng, song Cha d
viing

trung luu
(thuge
huyen Ninh San), song
La, song Quao d mien ha luu (thuge huyen Ninh Phude).
- He thdng cac song sudi nhd: phan bd d phia bac va phia nam tinh, song
Quan The (Ninh Phude), song Trau, song Ba Rau (Ninh Hai).
Nhin chung cac he thdng song ngan deu bat ngudn va ket
thiie
trong noi
tinh, do doe binh quan luu
vue
tii 7 -
15.
Tinh ed Dam Nai vdi dien tich
Idn
nhat la 650 ha da va dang khai thae
dua vao nuoi trdng thuy hai san, ngoai Dam Nai eon cd kha nhieu dam, hd nhd
khac.
7.7.2. Tinh hinh kinh te xd hoi tinh Ninh Thuan
Ninh Thuan nam tren cac true dudng giao thong xuyen viet khong xa dia
ban kinh te trgng diem Nam Bg va thanh phd Hd Chi Minh va nam trong cum
du
lich
Da Lat - Phan Rang - Nha Trang, ed cac
ciia
ngo ra bien, cd dieu kien
phat trien cang thuang mai va du lich.
Day la mot trong nhirng dia ban sinh sdng ciia ngudi Viet co, hien tai ed
khoang 28 dan toe, nhung dong nhat la ngudi kinh, ngudi Cham va ngudi
Rawcklai. Dan sd phan bd khong deu, tap trung chu yeu d cac dai ddng bang

ven song, gan cac true dudng giao thong va cac thi xa, thi tran. Viing mien
niii,
dat rgng, ngudi thua, mat do dan sd 25
ngudi/km^
ngudn
lao
dong 23.873 ngudi.
chiem 49,2% dan sd. Lao dong viec lam trong nen kinh te qudc dan la
179
ngan
ngudi, chiem 76% tdng ngudn lao dong. Chat lugng ngudi lao dong cua tinh con
thap,
khong ddng deu, can dugc dao tao va dao tao lai.
Ninh Thuan cdn la viing cd
lanh
hai rgng
18.000km^
la mot trong
nhiJng
ngu trudng quan trgng cua Viet Nam vdi 500 loai hai san, cho phep khai thae
mdi
nam 5 - 6 van tan. Day cung la dia phuang san xuat mudi
Idn
nhat ca
nude
vdi san lugng 130.000 tan/nam. Ngoai ra vdi dien tich
riing
Idn,
lam nghiep
cung

dugc
coi la the manh nhung khai
thae
chua hieu qua.
Trong phat
tviin
cay trong vat nuoi, Ninh Thuan bi ban che rat
Idn
ve
ngudn nude tudi. Cay
liia
chi dugc tham canh d Ninh
Phude
4.500 ha, Ninh Hai
3.500 ha, Phan Rang 2.000 ha, Ninh San 1.000 ha. Dien tich trdng bap khoang
S.OOOha,
trdng mi khoang
1.000
ha/ nam.
Cay thuc pham chu yeu la hanh, tdi vdi dien tich 450 - 500 ha/nam. Hanh
tay 200 - 300 ha phue vu noi tinh va xuat khau.
cay
eong nghiep va
cay
an qua
ehii
yeu la cay nho, khoang 2.500 ha, san
lugng 62.500 tan/nam; cay mia den nam 2010 cd 9.100 ha; cay
thude
la khoang

2.000 ha dat san lugng
5.000
tan/nam; cay bong vai mdi nam trdng dugc
2.000ha.
Cac vat nuoi chinh la bd, du
tinh
den nam 2010 cd
110.000
con, san
lugng xuat chudng 9,5 ngan tan; de
ciru
ed khoang 30.000 con va vSn tiep tuc on
dinh cho cac nam sau; du kien den nam 2010 cd khoang 100.000 con
Ign,
san
lugng xuat chudng 6,37 ngan tan.
1.2. Hien trang va tiem nang
sir
dung tai nguyen dat
tinh
Ninh Thuan
7.2.7. Hien trang
sudung
dat
Tinh Ninh Thuan nam d phia Nam viing Duyen hai Nam Trung bg
(DHNTB), d vi tri trung diem giao thong doc theo QL
lA,
dudng sat Thdng
Nhat va QL 27 len Tay nguyen. Toan tinh cd 5 huyen va 1 thi xa vdi 62 xa,
phudng, thi tran (mdi thanh lap them huyen Thuan Bac va 3 xa). Theo ket qua

kiem ke dat dai nam 2005, dien tich dat tu nhien toan tinh la 335.799,87 ha,
chiem 1,02 % dien tich toan qudc, chiem 7,54 % tong dien tich viing DHNTB.
Dat nong nghiep cd dien tich 261.961,51 ha, chiem 78,01 % tdng dien tich tu
nhien (DTTN) toan tinh (trong dd: dat san xuat nong nghiep la 70.382,65 ha,
chiem 20,96 % DTTN toan tinh; dien tich dat lam nghiep la 187.778,33 ha,
chiem 55,92 % DTTN toan tinh); dien tich dat phi nong nghiep cd 21.060,29 ha,
chiem 6,27 % DTTN. Dien tich dat chua su dung cdn 52.778,07 ha, chiem
15,72 % DTTN; trong dd dien tich dat ed the khai thae vao san xuat nong
nghiep khoang
19.300
ha, nuoi trdng thuy san 105 ha, lam mudi 540 ha va san
xuat lam nghiep khoang 14.000 ha.
Ddi vdi
da't
trong cay hang nam, cac he thdng canh tac can chiem den
69,4%,
da't rugng
liia
-
Iiia
mau chi chiem 30,6%, trong dd dat trdng mot vu
liia
mau chiem 27,38% dien tich. Ddi vdi dien tich dat nuang
rSy
chu yeu la nhd
nude trdi,
vSn
cdn quy mo kha
Idn,
len den 16.066ha (chiem 31,18% dat trdng

cay
hang nam. Dieu nay cho thay, dau tu thuy
Igi
de giai quyet nude tudi, tim
giai phap giu am cho dat de tang vu cay trdng la can thiet.
Cac
cay
trdng
lau
nam, nho va dieu la 2 loai
cay
trdng phd bien, sau dd
den cay bong va cay thude la.
Trong dat lam nghiep,
rirng
tu nhien bao phii gan het, chiem 95,24% dien
tich, tuy nhien phan
Idn
la
rimg
tai sinh ed do che phu thap. Dat cd rirng trdng
chiem 4,76% dien tich dat lam nghiep, trong dd khoang 70% dien tich rung
dugc trong tren dat eat hoac tren them phii sa cd it ddc.
Theo he thdng phan loai dat Viet Nam, Ninh Thuan ed 8 nhdm dat chinh
chia
thanh 24 dan vi phan loai dat. Dat dd va nau vang (dat
niii)
vdi tren 200
ngan ha chiem 58% dien tich dat toan tinh. Chi ed dat phii sa cd do phi tuang
ddi kha cdn lai phan

Idn
la cac dat ngheo dinh duang.
Cac loai dat thuge
viing
ddng bang ven bien:
+ Nhdm dat eat: gdm 3 loai, dien tich 13.418 ha, chiem 3,83% dien tich
dat tu nhien. Trong dd dat cdn eat trang vang: 2.169 ha; dat cat bien: 6.727 ha;
eon cat dd: 4.252 ha. Nhin chung phan dien tich tuang ddi ddng nhat, thanh
phan
ehii
yeu la cat va cat min da cd tich
liiy
miin.
Dat bi kho ban nang, muc
nude ngam sau, dat cd phan
ling
chua, ngheo mim. Loai dat nay
ehii
yeu trdng
rirng phdng ho. Mot sd dien tich vung dat thap cd dieu kien tudi dugc dua vao
trdng cac loai hoa mau nhu hanh, tdi, nho.
-I-
Nhdm dat man:
Nhdm dat man gdm 4 loai, dien tich 2.294 ha, chiem 0,67% dien tich tu
nhien, trong do dat man
sii
vet 417 ha d Dam Nai huyen Ninh Hai; dat man
nhieu 252 ha d Ca Na - Ninh Phude; dat man it va trung binh 1.150 ha d xa Hd
Hai,
Phuang Hai, Nhan Hai, huyen Ninh Hai. Dat man kiem 202 ha d Ninh Hai.

Cac loai dat man thudng phan bd d dia hinh thap hoac ven cac song dd ra bien
bi anh hudng cua thuy trieu. Ddi vdi nhdm dat nay d viing chu dong nude,
khong bi anh hudng cua thuy trieu ed the trdng
liia
va hoa mau, viing khong chu
dong nude thi san xua't mudi va nuoi trdng thuy san.
+
Nhdm dat phu sa:
Nhdm da't phu sa gdm 4 loai, dien tich 17.922 ha, chiem 5,2% dien tich
dat tu nhien. Da't phu sa dugc bdi hang nam 690 ha, phan bd ven song cai. Dat
phii
sa khong dugc bdi
11.736
ha, phan bd kha tap trung d hau het vung ddng
bang cua cac huyen, thi. Dat phu sa ngoai sudi 321 ha, phan bd rai rac ven cac
song sudi d viing ddi
niii.
Dat phu sa
gley
5.184h, phan bd d cac viing trung thap,
thudng bi ngap nude d huyen Ninh Phude.
Da't phu sa la nhdm dat tdt
ciia
tinh,
neu
ehii
dong dugc ngudn nude tudi
ed the thieh hgp vdi nhieu loai cay trdng. Nhdm dat nay dugc sir dung de trdng
Ilia,
ngo va cac loai hoa mau khac.

Cac loai dat viing ddi
niii:
4-
Nhdm dat xam gdm 3 loai, dien tich 87.343 ha, chiem 25,5% dien tich
tu nhien. Dat xam bac mau
phii
sa cd 27.454 ha; dat xam bac mau tren da mac
ma va da cat 29.289 ha; dat xam nau ban kho ban 30.700 ha.
+
Nhdm da't dd vang gdm 7 loai, dien tich 184.477 ha chiem 53,8% dien
tich tu nhien. Dat dd viing ban kho ban chiem 2.230 ha, dat dd
nau
tren da
bazan 3.990 ha, dat dd vang tren da set va bien chat 9.054 ha, dat dd vang tren
da Granit
154.895
ha, dat vang nhat tren da cat 2.959 ha, dat nau vang tren
phii
sa ed
9.119
ha, dat vang dd bien ddi do trdng
liia
2.230 ha.
+
Nhdm da't mau vang dd tren da mac ma axit cd dien tich
15.000ha,
chiem 4,4% dien tich dat tu nhien, phan bd d do cao tren 1000m.
+ Nhdm dat thung lung ddc tu cd dien tich 873 ha, chiem 0,25% dien tich
tu nhien, phan bd rai rac d cac khe sudi, thung lung, thieh hgp trdng
liia

nude va
mot sd hoa mau.
+
Nhdm dat xdi mdn tra sdi da cd dien tich 16.953 ha, chiem 4,9% dien
tich tu nhien. Dat bi rira troi bao mdn rat nhanh, tang da't mat bi trdi het, mat kha
nang san xuat ndng nghiep.
7.2.2. Tiem nang
svtdung
dat ndng nghiep
Tiem nang sir dung dat nong nghiep dugc tinh toan dua tren ca sd xem
xet mot sd yeu to da't dai nhu: dac diem tinh chat dat, do day tang dat va phan
bd do ddc dia hinh. Theo cac ket qua nghien
eiiii
cho thay da't cd kha nang sir
dung cho muc dich nong nghiep cua tinh nhin chung chiem mot ty
le
khiem ton,
chi chiem 42, 92% tdng quy da't, trong dd dien tich ed kha nang bd tri cac loai
hinh sir dung dat nong nghiep dat khoang 87.500 ha (26,04% tdng dien tich
tren).
Loai da't khong hoac it cd ban che chiem 6,96% tdng dien tich tu nhien,
ehii
yeu la dat
phii
sa song sudi, cd kha nang thieh ung cao vdi cac loai hinh sir
dung nong nghiep nhu cay an qua (tren dat phu sa khong dugc bdi), hoa mau va
cay an qua (tren dat phii sa ngdi sudi) va
liia
hoac
liia

mau
(tren
cac dat
phii
sa
gley hoac
loang
id).
Loai da't cd ban che trung binh chiem
31,54%
tdng dien tich tu nhien, chu
yeu la dat xam, dat ddc tu, dat man trung binh va it, cac dat dd va dat xam nau
viing ban kho ban, dat dd vang tren da set va bien chat, phan bd d dia hinh ddc
( <
8^)
va ed tang dat day > 50 cm. Cac loai dat nay ed kha nang thieh hgp d
muc trung binh den kha vdi cac loai hinh sir dung nong nghiep nhu liia hoac liia
mau (tren dat xam gley, xam loang
Id
va dat ddc tu); nuoi trdng
thiiy
san
nude
man va
liia
nude (tren dat man trung binh va it); hoa mau, cay eong nghiep hang
nam hoac lau nam, hoac lam ddng cd
chan
tha (tren cac dat dd va xam nau viing
ban kho ban, dat dd vang tren da set va bien chat, da't vang dd tren da mac ma

axit).
Loai dat cd ban che nhieu chiem 4,41% tdng dien tich tu nhien. Dien tich
cd kha nang bd tri cho san xuat nong nghiep dat khoang 7.400 ha.
1.3. Hieu qua kinh te su dung dat vung ban kho han
Trong nhirng nam qua,
ciing
vdi viec ung dung nhirng tien bg khoa hoc ky
thuat vao san xuat, nhieu mo hinh canh tac tren viing dat ban kho ban da dugc
ap dung nhu: mo hinh tudi tiet kiem nude cho cac loai cay trdng, sir dung vat
lieu
giir
nude tren cay trdng da dugc ap dung va mang lai hieu qua thiet thuc cho
san xuat nong nghiep
ciia
ngudi dan.
8
Theo danh gia cua Sd Nong nghiep va Phat trien nong thon, du kien tiem
nang san xuat nong nghiep cua Ninh Thuan den nam 2010, 2012 khoang 80.000
ha, tang 16.000 ha so vdi nam 2005, trong khi dd cac eong trinh thiiy
Igi
tren dia
ban tinh mdi
chi
dap
ling
khoang 48 - 49% dien tich da't nong nghiep. De cai
thien tinh hinh nay, Ninh Thuan da xay dung nhirng mo hinh tudi tiet kiem nude
cho cay trdng. Hien tai mo hinh nay da va dang dugc trien khai rgng khap tren
toan tinh. Hinh
thiic

tudi tiet kiem nude tren cay nho, tren cd phuc vu chan nuoi,
tren cay an qua, tren cay
liia
da gdp phan dang ke trong viec nang eao hieu qua
kinh te va tiet kiem lugng nude vao
miia
kho ban.
Ket qua nghien
ciiii
cho thay, neu ap dung phuang phap tudi truyen thdng
phai can den 9.072
m^
nude/ha/vu san xuat nho, thi ddi vdi mo hinh tudi nhd
gigt la 1.608
m^
nude/ha/vu,
tiic
la chi bang 17,8% (giam 82,2% lugng nude
tudi),
lugng phan bdn cung giam tir 20 - 25%, cac chi tieu sinh hge va nang suat
ciia
mo hinh tudi nhd gigt hau nhu khong khac gi so vdi mo hinh tudi truyen
thdng cua ndng dan. Do tiet kiem dugc phan bdn va nude tudi nen chi phi giam,
cho lai xuat khoang 1 trieu ddng/ha nho so vdi phuang phap tudi truyen thdng.
Rieng vdi cay
liia,
viec ap dung hinh
thiic
tudi tiet kiem da cho san lugng tang
tir 8,8 ta den 23 ta,

giiip
ngudi san xuat tang
Igi
nhuan tir 2,4 trieu ddng den han
6 trieu
ddng/ha/vu.
Qua trinh sir dung nhung vat lieu giu nude trong san xuat cay mau (cay
bap lai) cd the cho nang suat tang tir 10 den
15%,
hieu qua kinh te so vdi cac
phuang phap tudi truyen thdng tang tir 1,2 den 2 trieu ddng/ha/vu. Tuy nhien
viec sir dung cac dang che pham hda hoc chi mang lai hieu qua trong thdi gian
tir 2 den 3 nam dau sir dung, sau dd se ed cac phan
litig
phan giai cac hgp chat
hda hge gay chua hda dat.
Viec ap dung cac hinh
thiic
tudi tiet kiem ket hgp vdi sir dung cac che
pham vi sinh lam tang kha nang
giir
am cho dat la can thiet de nang cao hieu
qua sir dung dat.
1.4. Khai quat ve vi sinh vat sinh mang nhay
7.^.7.
Dinh nghia
Vi sinh vat sinh mang nhay la nhirng vi sinh vat ma ben ngoai thanh te
bao ed mot lap nhay hay dich nhay. Dd la mot lap chat dang keo cd do nhay bat
dinh (cdn ggi la giac mac) bao nhay ehii yeu la polisaccarit, ngoai ra cdn cd
polipeptit va protein.

Theo dieu tra
ciia
mot sd tac gia thi mat do cua mot sd vi sinh vat mang
nhay trong mot sd loai dat ddi
niii
d Viet Nam khoang
10^-10"^
CFU/g dat, tuy
thuge vao timg loai dat. Ngoai ra thi cac vi sinh vat ed kha nang sinh mang nhay
dang polisaccarit cd kha nang lam tang ket eau dat, lam giam su bay hai
ciia
nude trong dat.
7 ^.2.
ChUc
ndng sinh mang nhay cua vi sinh vat
Mang nhay bao ve vi sinh vat khdi su tdn thuang khi dieu kien moi
trudng khac nghiet, bao ve te bao vi khuan gay benh khdi hien tugng thuc bao
ciia
bach eau. Nguge lai khi khong cd mang nhay chiing nhanh chdng bi bach
eau tieu diet.
Mang nhay la nai du
tru*
nang lugng, de phdng khi thieu thiic an cd the sir
dung vd nhay nhu mot ngudn chat dinh duang. Khi thiic an can kiet vi sinh vat
se tieu thu dan chat dinh dudng cd trong vd nhay va lam cho vd nhay teo dan lai.
Vi sinh vat sinh mang nhay cdn ed nhieu
iru
diem dang dugc nghien
ciiu
va

img
dung, dac biet la kha nang cai thien do am cua cac viing dat ddc va kho
ban. Ddi vdi cac viing dat ddc va kho can, chiing cd kha nang giu nude, lam
tang do ben eau
triie
dat va lam giam xdi mdn.
1.43.
Tac dung cai tao dat cua che phdm Lipomycin M
Hien tai cd nhieu phuang phap de cai tao dat kho ban nhu: cac phuang
phap hda ly, ca ly, sinh hge, nhung ngay nay phuang phap sinh hoc dugc danh
gia la ed trien vgng ban ca. Cac phuang phap hda hge mac
dii
cd hieu qua
nhung van the hien nhieu khia canh han che. Vi du nhu cac chat giir am hda hoc
cd kha nang
hiit
nude gap hang tram
Ian
khdi lugng cua nd nhung hieu qua lai
phu thuge vao lugng bdn dau vao va kha nang giu nude giam dan theo thdi gian
vi chiing
bj
phan
hiiy
sau thdi gian khoang 8 den 12 thang.
Cac vi sinh vat tham gia hau het vao cac qua trinh ehuyen hda vat chat
trong he sinh thai dat, trong dd ddng vai trd khong nhd ddi vdi qua trinh cai tao
dat va dam bao cho
sir
phat trien mot nen nong nghiep ben

\arng.
10
Theo ket qua nghien
ciili eiia
Phdng nghien cuu cac chat cd boat tinh sinh
hoc (Vien
eong
nghe sinh hge - Vien Khoa hoc va Cong nghe Viet Nam) da
phan lap dugc mot bg chiing gidng vi sinh vat sinh mang nhay, trong do ed
chung na'm men da't Lipomyces starkeyi
PT7.1.
Chiing nam men nay ed dac
diixn
la sinh mang nhay, sir dung it
N2,
trao ddi nang lugng bang qua trinh oxi
hda
chii
khong len men cac ngudn ca chat. Do su trao ddi nang lugng ban che
nen nd sir dung cac ngudn cac bon rat phong
phii.
Nam men Lipomyces cd kha nang tdng hgp Lipit rat manh va tich
luy
trong te bao dudi dang gigt md, dac biet la chiing khong tiet chat beo ra ngoai
moi trudng nhu nhieu chung nam men khac ma nam trong te bao. Qua trinh
tdng hgp Lipit chiu anh hudng cua nhieu yeu td, quan trgng nhat la ty le
C/N
trong moi trudng. Tat ca cac chung nam men Lipomyces trir
L.anonahis
deu the

hien kha nang tao polisacarit ngoai bao manh. Nhd ed kha nang tao mang nhay
ma nhirng chiing nam men nay dugc phan lap tu dat cd y nghia
Idn
trong viec
cai tao dat trdng ddi
niii
trge,
dac biet la cac viing dat kho ban.
Dua tren dac tinh sinh hge cua chung nam men nay, cac nha nghien
ciiu
da xay dung quy trinh eong nghe san xuat che pham giu am dat ed ten thuang
pham la Lipomycin M va da thanh
eong
d quy mo thir nghiem. Che pham nay cd
y nghia rat
Idn
trong eong tac cai tao va bao ve dat, do cd kha nang giam
sir
bay
hai nude va tang do am dat,
giiip
cho dat tai xdp ban, tang sd lugng giun dat,
ddng vat khong xuang sdng va cac nhdm vi sinh vat cd ich khac d trong dat.
Che pham khong doc hai, an toan vdi he sinh thai dat va cdn cd kha nang cai
thien mot sd tinh chat ly, hda hge cua dat nhu: do chua
ciia
dat cd xu hudng
giam, ham lugng phot pho de tieu va cac cation trao ddi tang.
Che pham
giii

am dat Lipomycin M dugc eau thanh tir 2 thanh phan chu
yeu la vi sinh vat - Nam men Lipomyces va chat mang tinh bgt. Che pham nay
da dam bao dugc cac yeu eau: Khong lam anh hudng den su sinh trudng cua cac
nhdm sinh vat khac; ban than nhdm vi sinh vat trong che pham cd kha nang tdn
tai va canh tranh sinh trudng dugc vdi cac khu he sinh vat trong moi trudng dat
tu
nhien.
11
CHUONG
2.
DOI TUONG
VA
PHUONG
PHAP NGHIEN
CUU
2.1.
Doi
tirgng,
dia diem nghien
euru
Ddi tugng nghien
ciiu
la 3 loai dat chinh: dat xam nau viing ban kho ban
va da't man kiem dugc lay d huyen Ninh San, Ninh Phude, tinh Binh Thuan.
Che pham giu am dat "Lipomycin
M"
(Vien Cong Nghe Sinh hoc)
Dia diem nghien
eiiii
la Bg mon Thd nhudng va Mdi trudng dat, Khoa

Mdi trudng, trudng DHKHTN Ha Noi; Phdng Thd nhudng, Vien Quy hoach va
thiet ke ndng nghiep.
2.2.
Phuong
phap nghien
cihi
2.2.7.
Phuang
phdp bo tri thi nghiem chau vai
Bd tri 12 chau vai, mdi chau dung 10 kg da't xam nau dugc lay tir huyen
Ninh San, tinh Binh Thuan. Tren mdi chau deu trdng cay dau tuang va dugc
chia
lam
2
16:
L6 ddi chiing khong bdn che' pham
giiJ
am,
16
thi nghiem (TN)
bdn che' pham
giir
am Lipomycin M vdi lieu lugng 5 g/ chau, cac chau vai dugc
dat tren san thugng cd mai che va khong tudi nude trong sudt thdi gian thi
nghiem.
Do am cua da't dugc xac dinh tai cac thdi diem
15;
30; 45; 60 ngay sau
khi bdn che pham.
2.2.2. Phuang phdp nghien

ciiti
trong phdng thi nghiem
'
Cac chi tieu hda ly dugc phan tich tai phdng Thd nhudng, Vien Quy
hoach va Thiet ke Nong nghiep.
- Cac chi tieu hda ly dugc xac dinh theo nhung phuang phap thdng dung
hien nay trong cac phdng thi nghiem phan tich dat.
• Xac dinh thanh phan ca gidi theo phuang phap phan loai cua My
•
pH^ci va pHnoH
dugc do bang may pH Metter
• 0M% dugc xac dinh bang phuang phap Walkley - Black
12
• Xac dinh Nita tdng sd bang phuang phap Kendan
• Xac dinh Phot pho tdng sd bang phuang phap phuang phap so mau
xanh Molipden
• Xac dinh Kali tdng sd bang phuang phap quang
ke'
nggn lira
Cac chi tieu sinh vat dugc xac dinh tren mdi trudng thach dia Petri
theo
ehudn
ap dung cua Hiep hoi Khoa hge Dat My. Cac mdi trudng
dugc ap dung:
• Vi khuan: Moi trudng thach dinh dudng
• Xa khuan: Moi trudng Kuster va Williams
• Nam mdc: Moi trudng Czapek - Dox
• Nam men: Czapek - Dox - Propionate.
13
CHUONG 3. KET QUA NGHIEN

CUU
VA THAO LUAN
3.1.
Mot so dac diem ly hoa hoc
ciia
cac nhom dat nghien
euru
3.7.7. Nhdm dat do viing bdn khd hqn
Nhdm dat dd vung ban kho ban ed dien tich:
1.840,05
ha, chiem: 0,55%
dien tich toan tinh. Phan bd chu yeu d huyen Ninh San 877,70 ha va huyen Ninh
Phude 769,60 ha, dudi dang cac ddi dat dd.
Toan bg dien tich dat dd vung ban kho ban phan bd d cac cap do ddc <
20^;
trong do cd den 71% dien tich phan bd d do ddc <
8^
va chi cd
13,41%
dien tich la cd do ddc tir
15
den
20^.
Cac ket qua phan tich tinh chat ly hda hge cua dat dugc the hien nhu sau:
al Thdnh phdn
cagidi
Dat dugc lay tai cac thon d xa My San, huyen Ninh San la da't thit pha cat
vdi ham lugng eat dao dong tir 31.11 - 76.60%;
limon
tir 8.53 - 39.45%; set tir

14.87-26.59%.
b/ Dd chua cua dat
D pHH20
•
pHKCI
NS-10 NS-12 NS-14 NS-15 NS-16 NS-17 NS-19 NS-21
M^u
Hinh
1. Do chua cua dat do
d
My Son, Ninh Son, Ninh Thuan
14
Tren hinh 1 cho
tha'y
do chua cua
d^it
d
miie
chua vira den gan trung tinh.
PHHOH
dao dong tir 5.68 - 7.47, trung binh 6.83;
pH^a
tir 4.46 - 6.54, trung binh
5.84. Gia tri pH nude cho thay day la dieu kien thuan
Igi
cho viec trdng cac cay
bg dau, cay
thude la
va trdng mia,
luan

canh dieu tai dat nay. Tuy nhien su
chenh lech cua gia tri pH nude va
pH^ci
1^
0'^9
- 1,27 d muc tuang ddi cao, cho
biet da't dugc hinh thanh trong dieu kien khi hau nhiet ddi am cd su rira troi dang
ke cac cation kim loai kiem va kiem thd, tich luy nhieu sat nhdm la nguy ca gay
dat, anh hudng den su bat
Igi ciia
cay trdng. Tir ket qua phan tich nay can cd
dinh hudng cai tao va bao ve dat, tang cudng bdn phan chudng, bdn vdi va ban
che nhung tac dong gay chua dat.
cl
Hdm
luang
chat
hihi
cavd
N,
F,
K tdng so
{%)
2.500
2.000
1.500
1.000
0.500
0.000
• OM %

=1N%
P205%
K20%
NS-t) NS-T2
NS-14 NS-15
NS-B
NS-17 NS-19 NS-21
0 821
1.88
2 24 117 152 0 94 188
199
0.089
0134
0.151 0.101 0,106 0.078
0.123
0.140
0,03 0.201 0.178 0118
0153
0,044 0.150 0.175
018 056 0.61 0.61
0
76 0,26 0,55 068
0.90
0.60
0.30
(%
0M%
N%
P205%
K20%

0.00
Hinh
2. Ham
lirgng
chat huu ca, N, P, K tong sd cua dat do
d My Son, Ninh Son, Ninh Thuan
Tren hinh 2 cho thay dat ed ham lugng chat hiru ca d mure rat ngheo den
ngheo, dao dong tir 0.821 - 2.24%; ham lugng nita tdng sd d
miic
ngheo den
trung binh, dao dong tir 0.078 -
0.151%;
ham lugng photpho tdng sd d
miic
15
ngheo den kha, dao ddng tir 0.03 -
0.201%;
ham lugng kali tdng sd d
miic
ngheo, dao dong tir 0.018 - 0.76%.
Theo ket qua dieu tra cho thay
d^x
a mau NS-10, NS-16 la da't ddng cd
dudng nhu khong cd su cham bdn bd sung chat dinh duang tu qua trinh canh
tac.
Mau NS-14, NS-21 la dat trdng dau xen thude la; NS-12, NS-15, NS-17 la
da't trdng
thude
la; NS-19 la dat trdng tao.
Nhung

thong tin nay la ca sd giai
thieh tai sao ham lugng chat
hiiu
ca va nita tdng sd d cac
mau
dat khac nhau.
Ham lugng chat hiru ca tai dat d day thap vi diiu kien khi hau dia phuang ed
nhiet do cao, thuan
Igi
cho cac boat dong phan buy cac chat bdi vi sinh vat
thanh
CO2.
Ham lugng nita tdng sd trong dat thudng cd tuang quan ty le thuan
vdi chat
hiju
ca da dugc the hien kha ro net tren hinh 2. Ham lugng chat
bun
ca
va nita tdng sd d cac mau trdng dau xen thude la cao ban cac miu khac la do
sinh khdi cdn lai sau thu hoach va cd su bd sung nita tir qua trinh canh tac ket
hgp vdi ngudn nita dugc thuc hien bdi cac nhdm vi sinh vat sdng eong sinh vdi
r6
cay ho dau cung cap cho dat. Ham lugng P, K tdng sd trong da't rat thap la do
kali la nguyen td kim loai kiem
dt
bi rira troi bdi dieu kien tu nhien, ddng thdi
cac nguyen td nay bi lay ra khdi dat bdi cac san pham thu hoach nhung lai
khong dugc bdn bd sung trd lai.
Cac ket qua phan tich cac tinh chat ly hda cho thay dat dd
vting

ban khd
ban ed ham lugng cac chat dinh dudng thap, lai phan bd tren
nhirng
bac dia hinh
cao,
da sd la ddi
niii
thap va it ddc, ban
niia
lai nam trong khu vue khi hau ban
kho ban, khan hiem ve ngudn nude nen da gay rat nhieu khd khan cho viec canh
tac cung nhu khai thae cho nong nghiep ndi chung.
3.1.2. Nhdm dat xdm ndu viing bdn khd hqn
Nhdm dat xam nau vung ban kho ban phan bd rgng d tat ca cac huyen
trong tinh, chiing chiem hau het cac dang dia hinh eao hoac phang
trude niii
va
mot sd
niii
sdt trong viing bac them nay. Dien tich dat xam nau len den 94.570
ha; chiem 28,15% tdng dien
tich
tu nhien toan tinh, trong do: huyen Ninh Hai:
12.899 ha; huyen Ninh Phude: 29.162 ha; huyen Bac Ai : 23.660 ha; huyen
Ninh San :
28.651
ha; Phan Rang - Thap Cham: 198 ha.
16
Cac
sd

lieu nghien
ciJH
cho thay
cd
den 99,26% dien tich dat xam nau
vimg ban kho ban phan bd
d
cac
ca'p
do ddc
<
20^,
trong do chu yeu
la cd do
ddc
<
8^
dien tich cd do ddc >
20^
chi chiem 0,74% dien tich dat xam nau.
Cac ket qua phan
tich
tinh chat ly hda hge cua dat dugc the hien nhu sau:
a/ Thdnh phdn
cagidi
Cac mau da't lay
d
cac thon thuge xa Lam Son, huyen Ninh San la dat thit
pha cat va pha set vdi ham lugng cat dao dong tir 66.33
-

87.67%; limon tir 5.76
- 14.44%; set tir 6.27
-
27.91%.
Dat lay
d
cac thon thuge xa Quang San, huyen
Ninh Son cung la da't thit pha cat va pha set vdi ham lugng cat dao dong tir 53.33
- 88.09%; limon tir 3.86%
-
8.65%; set 8.23%
-
39.19%. Dat lay
d
cac xa Nhi
Ha, Phude San, Phude Vinh, huyen Ninh phude la dat thit vdi ham lugng cat dao
ddng tir 18.43
-
65.83%;
limon 13.17 - 48.15%; set 7.63 - 48.29%.
Cac dat xam nau viing ban kho ban Ninh Thuan
cd
thanh phan
ca
gidi
thay ddi
giira
cac phau dien kha
Idn,
tir thit nhe den thit trung binh. Do dat dugc

hinh thanh tren nhieu loai da me
mSu
chat khac nhau nhu sudn tich hoac
lu tich
granit, cac thanh tao xam nhap mawema axit, hoac tren cac tram tich
cd
thanh
phan hat thd, phan bd tren cac be mat bdc mdn san phang trong dieu kien khi
hau ban kho ban vdi
Idp
phu thuc vat ngheo nan.
b/ Dd chua cua ddt
pH
n
pHH20
•pHKCI
Mau
NS-01
NS-02 NS-03 NS-05
NS-07
NS-09
NS-1
1
NS-13
Hinh 3. Do chua cua dat xam nau
viing
ban kho han
Lam Son, Ninh Son, Ninh Thuan
17
•RijNG

TA'/
DT/
?ii
Da't d Lam Son, Ninh San d
miic
chua vira den rat chua (hinh 3),
pHnon
dao ddng tir 5.34 - 6.72, trung binh 6.28;
pH^a
dao dong tir 3.97 - 5.31, trung
binh
4.74. Gia tri chenh lech giira
pHnoH ^^
P^KCI
tuang ddi cao, dao dong tir
1.37 - 1.54, cho biet dat c6 tich luy nhieu sat nhdm. Ket qua nay cung phan anh
nhirng tac dong bat
Igi
ciia dieu kien dat ddi vdi nhu eau sinh trudng va phat
trien
eiia
cay trdng. Dat chua cd the tang cudng hda tan
AF"",
cac kim loai nang
gay doc cho cay trdng, lam tang kha nang cd dinh
lan
trong dat, anh hudng den
viec cung cap lan
dt
tieu cho cay trdng, ddng thdi anh hudng den qua trinh sinh

trudng va phat trien
ciia
sinh vat dat. De tang nang suat cay trdng va tao dieu
kien thuan
Igi
cho cac sinh vat dat
e^n
phai cd cac bien phap cai tao dat nhu bdn
voi va bd sung them phan
hiru
ca vao dat.
pH
DpHH20
•
pHKCI
NS-22
NS-24 NS-26 NS-28 NS-29
NS-31
NS
M^u
Hinh 4. Do chua cua dat xam nau vung ban kho han
Quang San, Ninh Son, Ninh Thuan
Dat xam nau d Quang San, Ninh San d
miic
chua it den rat chua (hinh 4),
PHHOH
dao dong tir 5.53 - 8.08, trung binh 6.48;
pH^a
tir 3.94 - 6.46, trung binh
4.94, chenh lech giira

pHnoH ^^
PHRCI
tir 1.12 - 1.62, cho thay do chua tiem tang
eiia
dat kha cao.
MSu
NS-24 la dat trdng liia 3 vu, mau NS-26 va
NS-31
la dat
trdng mia + san, vdi cac dieu kien canh tac khong tdt la nguyen nhan ca ban gia
tang do chua
ciia
dat. Mau NS-28 la dat chua sir dung, chua cd
sir
tac dong dang
ke
ciia
boat dong nhan tac, lam tang
tinh
dem
ciia
dat nen dat
it
chua, cd pH
nude d
miic
kiem yeu la di su cd mat dang ke
ciia
cac cation kim loai kiem va
18