الفهرس 
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Abstract
The present work aims to investigate the possibility of utilization
some locally available agriculture wastes like rice straw to produce
organic fertilizer to minimize the environmental pollution by
chemical fertilizers and/or the accumulation and burning the
agricultural wastes.
The target of this investigate was done by using compost technology
of the agricultural wastes by preparation of an enriched compost
using rice straw supplemented with organic amendments (farmyard
manure) and inorganic ones (bentonite, rock phosphate, elemental
sulfur, and urea. The heap was inoculated at construction and after 30
days with a mixture of lignocelluolytic inoculants to accelerate the
decomposition rate of composting process which was practiced by
aerobic composting. Moisture content was adjusted at each turning
time and maintained by addition of water to heap during turning to
maintain a moisture content level of 60%. The heap was turned and
mixed every 15 days till maturation (120 days) to provide aeration.
Also, a field experiment was conducted at newly reclaimed sandy
soils in Ismaillia Experimental Research Station by applying the
prepared enriched compost in order to: (1) to evaluate the response of
potato plant to integrated compost application combined with
rhizobacteria inoculation and different chemical N-fertilizer levels on
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growth, some nutrients uptake as well as yield and some yield
parameters of potato grown in sandy soils. (2) To select the most
favorable treatments for potato production (3) to evaluate the effect
of organic amendments, biofertilization, and level of inorganic
fertilizer on chemical characteristics of rhizospheric soil of potato
plants cultivated in sandy soils, in trail to reduce the agricultural
costs, decrease environmental pollution with inorganic fertilizers and
to maximize potato yield. All these targets were achieved in this
study. Three representative samples were collected at different period
for evaluation the changes and maturation of compost.
The obtained results from laboratory and field experiment could be
summarized in the following:
• Temperature inside the composting heap reached
maximum within 2 to 4 days after each turning.
Afterwards, its values declined to reach minimum
values at the end of each interval. Moreover, the
temperature values were higher at deep layers of the
heaps than near its surface.
• The values of bulk density gradually increased by
progressing the composting process. Also, values of
bulk density were greatly affected by essential C/N
ratio of raw materials.
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• pH values were decreased slightly in early interval of
composting process, but later increased to reach up
original values.
• EC values showed gradual increase during the
composting process.
• Regarding the changes of O.C. and O.M., the obtained
results showed a gradual decrease in O.C. and
consequently O.M. by time during the composting
periods.
• Concerning the changes in total N, initially, its values
increase from 1.19 to 1.81 % then it shows little
decrease reaching 1.50 %, thereafter, its values
increase till the end of composting process reaching
1.61%.
• Both total phosphorus and potassium showed a
gradual increase during composting process.
• As regards to the available phosphorus, its values
decreased during the beginning and then increases till
the end of composting process.
• The decrease in NH4
+ -N content to low levels during
composting process was associated with the
accumulation of No3
- -N via the nitrification process.
• Soluble –N was affected by decomposition intervals,
since its values increased in early intervals (60 days)
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then they gave a gradual decrease till the end of the
composting process.
• The initial ratio of NH4
+/ No3
- was 6.59 and decreased
to 0.40 at the end of composting process.
• In respects to total micronutrients, their values showed
a highly gradual decrease during the different periods
of composting process.
• Values of DTPA-extractable Fe, Mn, Cu, and Zn were
increased during the different periods of composting
process.
• Regarding C/N ratio, its values decreased with the
progress in the composting process.
• The CEC increased during the composting process
from 87.52 meq/100g and reached 97.44 meq/100g at
the end of the process.
• The ratios of extinction coefficient (E4/E6) in aqueous
extract decreases during the composting process which
indicates a large particle size and characterized with
humic acids more than fulvic acids.
• Mesophilic microbes showed a gradual decrease
during the composting process then it increases and
reached maximum at the end of composting.
Moreover, the actinomycetes were slightly decreased
then gave marked increase till the end of composting.
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However, the counts of mesophilic fungi showed a
slight increase until 30 days, and then decreased
gradually till the end of the composting process.
• Thermophilic bacteria, fungi, and actinomycetes gave
a sharp increase during the early periods of
composting process, and then gave a marked decrease
at the end of composting.
• Mesophilic cellulose decomposers recorded higher
increase until 60 days of composting process, and then
the numbers showed gradual decrease till the end of
composting.
• Phosphate dissolving bacteria showed a marked
increase during the composting process.
• Internal temperature in the heap gradually DROPped to
be similar to the ambient temperature.
• The pH in the compost heap incubated at 550C under
anaerobic conditions recorded an alkaline pH values
after 24 hours.
• The mesophilic/ thermophilic ratio of the total counts
of microorganisms showed that all ratios of
mesophilic/thermophilic bacteria, actinomycetes, fungi
were more than 1.
• As regards to cress, barley and kidney bean seed
germination test, results showed no inhibitory effect
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when compost water extract of the compost heap
compared to distilled water during the germination
test.
• The color of the final product after sufficient period of
maturation was dark brown to black in color and is not
water soluble.
• The unpleasant odor decreases during the first stages
of the bio-oxidation phase and particularly disappears
by the end of the process and an earthy smell like the
smell of the soil and texture is loose.
• The overall carbon dioxide evolution rate was
relatively low and exhibited no linear peak as a result
of a reduction in metabolic activity, due to the
decrease of readily available organic carbon, which
reflected a reasonable degree of stability.
• Coliform bacteria as well as Salmonella and Shigella
were not detected at the end of composting process.
• Irrespective of N-levels, addition of compost at high
rate (10 tons/ fed) increase soil EC, OM, soluble-N, as
well as available P and K, also the higher results were
obtained in treatment combing both compost at rate
(10 tons/fed) with rhizobacteria inoculation.
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• Increasing application rate of N-fertilizer (from 37.5 to
150 Kg N/fed) to sandy soils led to slight increases in
EC, OM, soluble-N, as well as available P and K.
• Addition of compost at the higher rate resulted in
enhancement of biological activity which expressed by
dehydrogenase activity.
• Utilization of compost and mineral-N fertilizer at
different rates led to significant increase in the
vegetative growth of potato plants cultivated in sandy
soil.
• Results revealed that inoculation of rhizobacteria led
to significant increase in total chlorophyll content,
while have no significant effect on shoot and root dry
weight as well as root surface area.
• Utilization of compost led to significant increase in
NPK content of shoot and root.
• Irrespective of compost amendment, N-levels have
significant effect on root NK contents, shoot NP
contents, while have no significant effect on root P
content and shoot K content.
• Utilization of compost and levels of mineral-N led to
significant increase in tuber yield and quality (PK
contents, protein, starch and carbohydrate). Moreover,
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inoculation with rhizobacteria mostly increased the
potato yield and its quality.