The Green Mountain), eastern Libya, as well as the Alghiran
Agricultural Institute west of Tripoli (Alzobaidy and
Mohammad 2003).
The Faculty of Agriculture at the University of Tripoli
was established (June 1966) as one of the colleges of the
Libyan University, and the study started at that time with
three departments: the Soil and Water Department, the
Department of Plant Production, and the Department of
Animal Production. The first class, which consisted of a
batch of 42 students, was accepted at the beginning of the
1966/1967 academic year. From this date, the start of the
study of soil microbiology was one of the specializations and
courses taught in the Soil and Water Department. After the
first batch of 29 graduates in the year 1970, the number of
graduates developed until the school’s cumulative number in
the period 2009/2010 reached 8771 graduates.
Beyond the University of Tripoli, other agricultural colleges were established in the succeeding years. In 1975, the
Faculty of Agriculture was established at the University of
Omar Al-Mukhtar in the Al Jabal Al Akhdar region in
eastern Libya. The Soil and Water Department was one of
the departments in the college. The Faculty of Agriculture
was established in Sabha University in southern Libya in
1983, which numbered 815 students until 1996. In 1988, the
College of Veterinary and Agricultural Sciences was established in Zawia, west of Tripoli. The Faculty of Agriculture
at Misrata University was established and opened in 2015 in
the city of Misrata, east of Tripoli. All of these colleges are
studying soil microbiology as one of the courses in the Soil
and Water Department.
7.2 Climate Diversity in Libya and Its Impact
on Microbial Diversity
Libya occupies a wide area of 1,777,500 km
2 located
between the latitude 32° 58′ and 18° 45′ N, and between the
longitudes 9° 18′ and 24° 59′ E, which makes it characterized by a diverse climate. North of Libya is characterized by
the climate of the Mediterranean Sea, which is represented in
the coastal strip and extends a distance of 1900 km along the
coast of the Mediterranean Sea. This area does not exceed
10% of the total area and differs in breadth from one place to
another. The average rainfall in this region ranges from 300
to 600 mm, and average temperatures range between 25 and
40 °C in the summer and 0 and 14 °C in the winter, which
allows vegetation to grow with different intensity and species according to the prevailing environmental conditions.
As for most of the area located south of the coastal strip,
which is estimated at about 90% of the total area, it falls
within the desert climate or within the arid and semi-arid
areas, which are characterized by the lack or scarcity of
rainfall, and thus results in scarcity or lack of vegetation
(Zekry 2005; and Environment Public Authority 2008).
Although the Libyan soil, in particular, varies, in general it is
very similar in its properties to many other dry areas.
The climate diversity, in turn, leads to biological diversity
especially in the vegetation cover; therefore, microbial
diversity exists, in particular within the distribution of microorganisms in soil layers in terms of quantity and quality,
each according to the prevailing climatic conditions. The
absence of vegetation and the scarcity of rain resulted in little
or no organic matter in most arid areas, and since most of the
microorganisms in the soil are heterotrophic species and
depend entirely on organic matter, the microbial activity is
almost non-existent in desert soils, which fall within the
scope of arid and semi-arid soils. As for the areas that fall
within the Mediterranean climate, the microbial activity
depends quantitatively and qualitatively on the type of vegetation, the moisture content, and the percentage of organic
matter, which are completely different from the dry areas.
7.3 Soil Bacteria in Some Regions of Libya
Microflora of rhizospheric soil and rhizoplane portions of
Aristida coerulescens (naturally occurring in the Libyan desert) were different in counts and isolates in the different root
zones. The root base contained the lowest numbers of microflora (bacteria and fungi), while the root tip included the
highest counts (Naim 1965). Other investigations dealing
with the effect of plants on the microbial rhizosphere population were extended to reveal the microbiological occurrence
in different horizons of a soil profile corresponding in length
of root regions. Bacteria were most abundant, followed by
Actinomycetes, while fungi were less abundant and more
restricted in their distribution. The three groups of microorganisms varied markedly in the rhizosphere of the plants. The
plant’s age had a great influence on the frequency of occurrence of the different microorganisms. One strain of bacteria,
six fungi, and the members of the grey series of Streptomyces
were dominant. Actinomycetes and fungi diminished with
the depth of soil, while the bacterial counts increased (Selim
and Khalil 1979). The results of these studies, which are
considered somewhat old, agreed with a more recent study,
which attempted to identify the effect of the growth of different plants on the microbial community in the soil of rhizospheres by tracking the numbers of three microbial groups
(bacteria, fungi, and Actinomycetes) during the different
growth stages (germination, flowering, and maturity), with
two types of plant roots (leguminous and grass). It turns out
that the numbers of bacteria and fungi in the rhizosphere of
both plants increase as the plant ages, and then starts to
decrease during the ripening stage. As for Actinomycetes,
their numbers in the root zone increased in the last stages of
growth (Al Hammadi 2014).
92
E. A. Ferjani et al.
Agricultural Institute west of Tripoli (Alzobaidy and
Mohammad 2003).
The Faculty of Agriculture at the University of Tripoli
was established (June 1966) as one of the colleges of the
Libyan University, and the study started at that time with
three departments: the Soil and Water Department, the
Department of Plant Production, and the Department of
Animal Production. The first class, which consisted of a
batch of 42 students, was accepted at the beginning of the
1966/1967 academic year. From this date, the start of the
study of soil microbiology was one of the specializations and
courses taught in the Soil and Water Department. After the
first batch of 29 graduates in the year 1970, the number of
graduates developed until the school’s cumulative number in
the period 2009/2010 reached 8771 graduates.
Beyond the University of Tripoli, other agricultural colleges were established in the succeeding years. In 1975, the
Faculty of Agriculture was established at the University of
Omar Al-Mukhtar in the Al Jabal Al Akhdar region in
eastern Libya. The Soil and Water Department was one of
the departments in the college. The Faculty of Agriculture
was established in Sabha University in southern Libya in
1983, which numbered 815 students until 1996. In 1988, the
College of Veterinary and Agricultural Sciences was established in Zawia, west of Tripoli. The Faculty of Agriculture
at Misrata University was established and opened in 2015 in
the city of Misrata, east of Tripoli. All of these colleges are
studying soil microbiology as one of the courses in the Soil
and Water Department.
7.2 Climate Diversity in Libya and Its Impact
on Microbial Diversity
Libya occupies a wide area of 1,777,500 km
2 located
between the latitude 32° 58′ and 18° 45′ N, and between the
longitudes 9° 18′ and 24° 59′ E, which makes it characterized by a diverse climate. North of Libya is characterized by
the climate of the Mediterranean Sea, which is represented in
the coastal strip and extends a distance of 1900 km along the
coast of the Mediterranean Sea. This area does not exceed
10% of the total area and differs in breadth from one place to
another. The average rainfall in this region ranges from 300
to 600 mm, and average temperatures range between 25 and
40 °C in the summer and 0 and 14 °C in the winter, which
allows vegetation to grow with different intensity and species according to the prevailing environmental conditions.
As for most of the area located south of the coastal strip,
which is estimated at about 90% of the total area, it falls
within the desert climate or within the arid and semi-arid
areas, which are characterized by the lack or scarcity of
rainfall, and thus results in scarcity or lack of vegetation
(Zekry 2005; and Environment Public Authority 2008).
Although the Libyan soil, in particular, varies, in general it is
very similar in its properties to many other dry areas.
The climate diversity, in turn, leads to biological diversity
especially in the vegetation cover; therefore, microbial
diversity exists, in particular within the distribution of microorganisms in soil layers in terms of quantity and quality,
each according to the prevailing climatic conditions. The
absence of vegetation and the scarcity of rain resulted in little
or no organic matter in most arid areas, and since most of the
microorganisms in the soil are heterotrophic species and
depend entirely on organic matter, the microbial activity is
almost non-existent in desert soils, which fall within the
scope of arid and semi-arid soils. As for the areas that fall
within the Mediterranean climate, the microbial activity
depends quantitatively and qualitatively on the type of vegetation, the moisture content, and the percentage of organic
matter, which are completely different from the dry areas.
7.3 Soil Bacteria in Some Regions of Libya
Microflora of rhizospheric soil and rhizoplane portions of
Aristida coerulescens (naturally occurring in the Libyan desert) were different in counts and isolates in the different root
zones. The root base contained the lowest numbers of microflora (bacteria and fungi), while the root tip included the
highest counts (Naim 1965). Other investigations dealing
with the effect of plants on the microbial rhizosphere population were extended to reveal the microbiological occurrence
in different horizons of a soil profile corresponding in length
of root regions. Bacteria were most abundant, followed by
Actinomycetes, while fungi were less abundant and more
restricted in their distribution. The three groups of microorganisms varied markedly in the rhizosphere of the plants. The
plant’s age had a great influence on the frequency of occurrence of the different microorganisms. One strain of bacteria,
six fungi, and the members of the grey series of Streptomyces
were dominant. Actinomycetes and fungi diminished with
the depth of soil, while the bacterial counts increased (Selim
and Khalil 1979). The results of these studies, which are
considered somewhat old, agreed with a more recent study,
which attempted to identify the effect of the growth of different plants on the microbial community in the soil of rhizospheres by tracking the numbers of three microbial groups
(bacteria, fungi, and Actinomycetes) during the different
growth stages (germination, flowering, and maturity), with
two types of plant roots (leguminous and grass). It turns out
that the numbers of bacteria and fungi in the rhizosphere of
both plants increase as the plant ages, and then starts to
decrease during the ripening stage. As for Actinomycetes,
their numbers in the root zone increased in the last stages of
growth (Al Hammadi 2014).
92
E. A. Ferjani et al.