الفهرس 
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Abstract
The following lines summerize the various topics which
were handled in the present in~estigation to study the humus
substances isolated from organic matter of alluvial soils at
Fayoum Governorate.
The method of introducing this surrmary follows to a
great extent the line of approacb used in the presentation
of the various topics dealt with tn this manuscript.
1- The texture clases of soils under investigation was
sandy loam, loam, clay loam and clay.
2- CaC03 content of soils ranged between 1.9 to 11.5 %,
the highest content was found in Sunnoris district.
3- Soil water saturation percent (S.P.) ranged from 37.5
to 100 %.
4- Soil salinity: (the Ee values) of soil samples ranged
t •
from 0.93 to 15.9 mmhosl em! 25°C.
...
5- The pH of soil samples was generally neutral or
slightly alkaline, ranging between 7.3 and 1.9 .
._ ..- -_ .. - --------_._-----
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6- Soluble cations: Na+ cations were characterized by
its highest amount in the extract of the investigated
soils relative to .Ca +2 followed by ~~ +2 and K+ •
7- Soluble anions: HCO; content of the soil samples
ranged from 1.5 to 5.0 meq ~ _, while a very wide
range in the soil content of CI anions were observed
i•e . from 4 t0 140 me q /1. Moreover, 504-2 ions were
fluctuating between 2.9 and 64.8 meq /1.
. 8- Soil organic matter contents were relatively low throughout
the studied samples ranging (from 0.58 to 1.45 %).
9- Total nitrogen content of soil samples ranged between
0.036 to 0.140 %.
10- The variation in the C/N ratio was within a relatively
narrow range (from 4.9 to 9.2).
11- The obtained data after extraction with DTPA for the
micronutrients,elemen ts , Fe, Mn, Cu, and Zn showed tha t
this values ranged from 6.0 to 9 ppm for Fe, 6.4 to
\
11 ppm for Mo, 2.8 to 5.4 ppm for Cu and 0.8 to 2.8
ppm for Zo.
12- Extractable Fe, Mo, Cu and Zn with 0.1 MNB.4P2Cl.r- 0.1 ~ NaCH
mixture showed that the values of these micronutrieots
ranged between (3.5 to 8.5 ppm Fe), (0.5- 2.5 ppm Mn),
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(2.0 to 12.5 ppm Cu) and (Zero- 0.5 ppm Zn).
B) C-h-a-r-a-c-t-er-i-s-t-i-c-s----o-f--h-u-m-u-s---s-u-bs-t-a-n-c-e-s-:
1- Data showed that humic acids predominated over
fulvic acids in the studied samples and both were
found in the upper layer in higher amounts than the
lower one.
2- The total carbon content of humic acid ranged fronl
19.5 to 23.3 96 in the surface soil layer,and fran 18.5
to 19.3 % in the lower one.
3- The ratio of CHA/ CFA seems to decrease with depth,
since their vu lue s ranged from 1.09 to 1.44 in the
surface soil layer while they ranged from 1.06 to
1.13 in the subsurface ones.
4- Data showed that humin content was inversely proportional
to humic acids in general.
[ .
5- Iron content oC hwnic and fulvic ucids
Humic acid isolated from soil organic matter con-’
tained high values of total Fe content than that of
Culvic acid. Thc vulucs runged from 2.0 to 6.5 ppm
for the former, and 0.5 to 4.5 ppm for the latter.
Moreover, a considerable high values of tolal Fe
content were combined with hwmic acid extracled frQffi
Manshate Tantawy at the district of Sunnoris, its
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values ranged from 6.0 to 6.5 ppm. On the other hand,
low values were noticed in the district of Tameya (Kasser-
Rashwan) ranging from 2.0 to 2.5 ppm. Total Fe in soil
was observed in moderate amounts, ranging from 4.0 to 4.5
ppm (Abshway district) at Aboxa and Shakshuk village (at
Sunnoris district ).
Ultraviolet spectra of the samples were characterized
by a pronounced decrease of absorbance with increasing the
wave length, showing nether minimum nor maximum absorption
bands.
Moreover, UV spectra of fUlvic acid has a lower optical
densities than that obtained from the humic acid fraction.
The main bands were observed in the IR spectra of
the humic acid. It showed 8 broad band in the region from
3200 to 3520 cm-l characterizing hydrogen-band of OH groups.
while the bands at 1400, 1230 and 1200 cm-l, are characterizing
carboxylic, -OR deformation of CO2” and phenolic OH,
stretching respectively. The bands at 1720 and 1625 cm-l
were assigned to a weak shOUlder for C = 0 and a strong
absorption tor -OOOH groups respectively.
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Major absorption bands in the 1ft spectra of the
isolated fulvic acids resembles with those obtained
of humic acid except for the following differences
a- The band noticed at 2850 cm-l was assigned to
carboxylate ion.
b- Strong bands were observed at 1400 cm”-l reflecting
large quantities of aliphatic structure •