الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
This investigation was carried out to study the
changes in so11 properties of some existing fish farms
in Egypt.
Three fish farms that differ in their location
and structure dates were selected’, namely Al-RaswB ( Port
Said), El-Wahal (Kafr El-Shaikh), and Bl- Serow (Dakahlia)
Each farm was subject to various ,stages, that
include leaching, flooding with water through a period
of fish growth/the addition of fertilizers durin~ the
rearing of fish, and the last stage was after drainage
of the ponds and harveBtin~ the fish.
Soil samples were taken from the 0-25 cm, 25-50
em, 50- 60 cm, and 60- 120 ca layers. !hese soil samples
were physically and cheaically analyzed.
Coapari ••n was carried out with the 8011 samples
taken fro. the soll be:to:re :t18h ~&1’Wl1n&.
The ef:tect of fish :t&rll1D& on .0:1.1 piQ’81cal and cheldcal •
properties coUld be au•• eri ••• aa tellows I
1- The tiDe f’ractioDS (c1.&y aDd .n,,) 1DCreased, while
the sand :trac”ion d8c”_4 ~ .oat lqera o~ profile.
2- There was no marked change in pH during the
~rowth season. However, pH values decreased with
depth indicating the activity of’ anaerobic microorganisms
producing CO2-
3- There was a decrease in soil salinity, however,
the EO values increased with depth.
4- Soluble Be. decreased rapidly first by leaching then
by flooding; Na concentration increased with depth.
. - 5- Soluble K also decreased by leaching and flooding
but its decrease was generally lower than Na.
6- The concentration of’ Oa at the end of study was
between one to nine tenth of the original levels.
A aarked decrease occurred in 11& concentration
parlicularly in the upperl8\fers.
7- 1i08t of’ the chloride aalta were reaoved S DOD
&:tter the 1each!.D& then lIy tlood1D&, and C1- Concentratlo:
Q lDcreased .ith depth •
8-
There ••.• DO _8IIUZ’<le CQ•). and in the Sa.8 tIme
HCOj decreased ’7 leach±D4 1Iut increased with flood1D&
parllcu1ar17 in the aurl’ace l~er.
9- 504’ decreased •• a l.”Weul t :o~ the waterloM1n& Condltlol111
in a ••• 1i1l.l”,.p. h_ftr, It lDcreased
with depth.
10- The exchangeable base content (CEC) increased
upon utilization of the soil as fish ponds, in
most layers of the 80il profiles.
11- Although the initial leaching decreased exchangeable
Na in the saline soils, there was an ultimate
increases in exchangeable Na’at the end of
the growing fish season, particularly were the
floodin& water was saline.
12- Exch~eable K were slightly increased in some
farms, and a sliBhtly decrease was occurred in
the other farms.
1)- bchangeable Ca increased, in &1- ’1ahal and the
two surf’ace layers of Bl- Serow farm, while it
decreased in Al- Ra8Wa and the deep layers of Rl-
Sera. fara. Exchan&eable Jl& increased nearly in
all sites, the !Dare •••••.• aore1D the sur1’aee
l”era.
14- SodiUli adsorptiDD ratio (~) and exchan«eable
80diUII percent8&e (&V),. wre lIula.1ectto decrease
upon utUisat:l.oJl .t the •• U _ ~l.ah far.-. The
BSP ••••.•.•• bieber at tibia .ad ot .”wi,., thi8 is
excb&D&e c.pacity
parlloular17 1Jl tile ”’p 1a;rera •.
15- Available phosphorus increased by flooding and
fertilization.
16- Also, or&anic matter was increased in moat fish
farms specially when the farms received an fresh
water.