The Influence Of Priming Two Cucumber Cultivar Seeds

J. Duhok Univ. Vol.13, No.1, (Agri. And Vet. Sciences) Pp 82-89, 2010
which is caused by rainfall, snowfall and
runoff flow, will also increase the turbidity of
water. Suspended materials include soil particles
(clay, silt, and sand), algae, plankton, microbes,
and other substances. These materials are
typically in the size range of 0.004 mm (silt) to
1.0 mm (sand). Turbidity can affect the color of
the water. A variety of methods to estimate
seasonal suspended sediment yield in a mixed
land-use catchments they have examined.
Despite the inherent uncertainty, all estimates of
catchments sediment yield are found to be high
with respect to erosion plot studies from the
local area, and this suggests the importance
channel erosion as major sediment sources, a
finding consistent with other regional studies
.Usually, we measure turbidity to provide a
cheap estimate of the total suspended solids or
sediments (TSS) concentration (Kg dry soil
weight /m 3 water).Turbidity is measured using
the techniques of turbid meter or nephelometry
and is expressed in arbitrary units
(Nephelometric Turbidity Unit, NTU). The
direct relationship between turbidity data and
suspended solids concentration depends on many
factors, including particle size distribution,
particle shape and surface condition, refractive
index of scattering particles and of the
suspension medium and wavelength of the light.
Another even cheaper method is to use an
inexpensive devise called "Turbidity Tube" is a
simple adaptation for streams of the "Secchi
disk" technique for lakes. It involves looking
down a tube at a black and white disk and
recording how much stream water is needed to
make the disk disappear.
MATERIAL AND METHOD
Study locations
Duhok river catchments consist of following
secondary laterals , Bagloor, Sendor, Garmava
and Khazava catchments , the total catchments
area is 133.8 Km 2 the site between latitudes (36 o
52 - - 37 o 01 - N) and Longitude (42 o 51 - - 43 o 06 -
E) .The highest mountain peak at Bakhar (1381
m) above sea and the lowest outlet point is 560m
above sea, the attached morphometric map (Fig
.1) showing the site with scale (1:110000)(
Aomer , 1999) Garmava river length is
(14.1Km) the catchments shape as triangle, it is
far Duhok city about (5Km) . Duhok Dam
watershed climate region varies continually
between dry in summer and wet in winter ,the
rain fed area in the watershed is highly to
moderate slopes and cultivated with venues and
grain ( Hammed,2004) . Physical soil analysis of
Duhok watershed show that the most soil,
contained highly clay material, which about
more than 36% and it's classified as silt clay soil
with normal to moderate acidity. Only 25% of
Duhok watershed was covered with forest
(Gulcur and Kettaneh, 1972) but now day is less
than the mention percentage even though the
governorate cultivated 2.6% of forested trees as
well as 6.5km of wattle fences and constriction
about (3250m 3 ) prevent check dam in gullies to
reduce surface runoff then reduce water erosion
in the region. The erosion is their active due to
the sever slope and the rate of deposit
sedimentation is high .The main purpose of this
study is to estimated the seasonal sedimentation
for the Duhok dam watershed through
continually samples during the seasonal runoff
which outlet to the Duhok river due to estimate
their turbidity and to find the unique relationship
between turbidity and suspension concentrations
using turbidity meter (HACH-2100A).Turbidity
can be measured in the laboratory and also onsite
in the river by a handheld turbidity meter.
The meter is calibrated using standard samples
from the meter manufacturer. Six glass of vials
shows turbidity standards of (0.6, 1, 10,100,
500) and (1000 NTUs). Once the meter is
calibrated to correctly read these standards, then
turbidity of runoff suspended water samples can
be taken.
The methods and equipment used for
sampling suspended sediment are different from
those used for deposited sediments. Also
sampling methods for measurements of the
quantity of sediment in transport are different
than for measurement of sediment quality. The
reason for these differences reflects the fact that
sediment quantity must include the sand size
fractions which are unequally distributed in
depth, whereas sediment quality focuses on the
silt and clay fraction which is not depthdependent.
For bottom sediments it may be
necessary to collect deposited sediments with
minimum disturbance in order not to lose the
fine material on the sediment surface, or because
the vertical distribution of the sediment
components is important.
Turbidity measure with nephelometeric
turbid meters is considered a good method for
estimating suspension concentration in rivers
(Lewis 1996).Measuring turbidity can be done
by measured using either an electronic turbidity
meter or handheld turbidity tube. Both methods
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