النشر العلمي

  • Land Use/ Land Cover Change Detection Due to Urbanization, Case of Study - Southern part of Khartoum.

Overpopulation has become obsessed haunt the whole
world, especially in developing countries due to
continuous migration from rural areas to large cities and
towns, as a result, these cities have greatly expanded and
extended in all directions to accommodate those
newcomers, this expansion has been at the expense of
vegetation cover. In this study, Khartoum city also
underwent a considerable population growth during the
last decades, as a result, a part of the green belt South of
Khartoum has been chopped down and converted into
residential areas, e.g. Jabra district, Abuadam district,
Al Azhari district, etc. This study aimed to point out the
effect of urbanization on vegetation cover of Khartoum
city using Remote Sensed and GIS data as integrated
tools for land use change and land transformation over
39 years (1972 – 2011). Satellite images were obtained
from the USGS Global web site as the main data for
interpretations to create land cover maps of the study
area and to locate the location. Three false colour
composite (FCC) subsets images from Landsat TM and
ETM+ were used in this study. An image of 1972 was
enhanced by a Thematic Mapper (TM), while the 2006
and 2011 images were Enhanced using Thematic Mapper
Plus (ETM+). Landsat TM 1972 was used as a reference
image, while the images ETM+ 2006 and 2011 were used
to assess the change detection. ERDAS IMAGINE 9.2
and Arc 9.3 software were used as the processing and
analyzing tools; whereas ERDAS software is used in
obtaining multi-spectral classifications. The results show
that there is a significant decrease of vegetation from
29% in the 1972 to 8% in 2006, bare land decreased
from 20% to 2%; while urban areas increased from 47%
in 1972 to 85% in 2006, in addition to an insignificant
increase in water bodies. The study concluded that RS
and GIS are effective tools to assess land use land cover
change, which revealed that: the Southern part of
Khartoum shows a remarkable land cover change due to
urbanization that will seriously endanger the whole state
if no serious attempts or preventive measure were taken
to mitigate its effect on vegetation cover, which in turn
will affect the climate, because one of the main causes of
the climate change is deforestation.

published in Journal of Natural Resources and Environmental Studies

  • Detection of Tree Species Dynamic Changes On Savannah Ecology through Diameter at Breast Height, Case Study- Heglieg Area, Sudan

The present study was conducted at Heglieg which
is a small border town in South Kordofan state in
Sudan. The remark activity in this area regarding
oil production and new boundary between Sudan
and South of Sudan needs to be investigated
towards species composition and formula as
natural habitat for Savannah. The study
conducted by using Diameter at breast height,
(dbh) and height (h) as factors of growth indicator
and tree species succession.
The present study provides a procedure for the
evaluating direction of the trend of changes in
forest and tree cover and their dynamics in
relation to land use system in an important area in
the southern region of Sudan. As it has been
possible to identify five categories of forest and
tree cover, dynamic changes within and between
these categories has been used in the context of
addressing indicators as tools for monitoring
changes.
Landsat TM satellite scene of the area was used as
a base map for the determination of the strata and
distribution of the stratified sample plots. GPS was
used for field work to identify the position of each
sample plot in the ground and diameter at breast
height over bark (dbh) and total tree height (h) for
all trees were measured. Computer Packages SPSS
16.0 for Windows and Microsoft Excel version 17.0
were used for analysis and average dbh, h, basal
area and volume were calculated as well as relative
abundance, relative dominance and relative
frequency in each strata. The results reveal that,
dbh and total tree height can be used as a factor of
tree species dynamic change detection where they
represent a good indicator for site index.

published in Journal of Natural Resources and Environmental Studies

  • Linear and Non-linear Regression Equations for Estimating the Crown Diameter of Three Sudanese Edible Trees

Abstract_ This study was carried out at El-Nour Natural
Forest Reserve, Rosaries district, Blue Nile State. The
objective of study is to use linear and non-linear equations
for estimating crown diameter (cd) from diameter at breast
height (dbh) for three Sudanese edible tree species namely,
Balanites aegyptiaca (L.) Del, Lannea fruticosa (Hochst. Ex
A. Rich.) Engl, and Sclerocarya birrea (A. Rich.) Hochst.
For each species, dbh, total height and crown width were
measured. DataFit-9 statistical package of the Oakdale
Engineering was used to fit the selected equations. Akaike’s
information criterion (AIC), adjusted coefficient of
determination (Ra2), root mean squared error (RMSE),
numerical and graphical analyses of the residuals were
used for evaluating the models.
The results showed that, all fitted equations gave
acceptable results with Ra2 0.6000 - 0.6409 and RMSE
1.1165 - 1.1464 for Balanites aegyptiaca, 0.6400 - 0.6804 and
1.4026 - 1.4337 for Lannea fruticosa and 0.6712 - 0.7741
and 2.0278 - 2.0326 for Sclerocarya birrea respectively. The
AIC values vary from 114.40 for Balanites aegyptiaca to
292.373 for Sclerocarya birrea. The study concluded that,
the crown diameter could be estimated by the mean of
diameter at breast height as it is easy to measure for
ground-based inventory and stand structure determination.
The equations examined in this study produced reasonably
precise estimates for crown diameter and could be used to
predict the crown diameter of the species under
consideration.
The study recommended that, Future research is needed
with a greater variety of site and stand conditions in
addition to a greater variety of tree sizes and ages. It should
be noted that, the models used by this study were based on
data collected from El-Nour Natural Forest Reserve in Blue
Nile State; therefore, it should be used with caution outside
this area.

published in Journal of Forest Products & Industries

  • Diameter at Breast Height-Crown width Prediction Models for Anogeissus leiocarpus (DC.) Guill & Perr and Combretum hartmannianum Schweinf.

ABSTRACT— This study was carried out at El-Nour Natural Forest Reserve, Rosaries district, Blue Nile State with objective of predicting Crown width from Diameter at Breast Height for Anogeissus leiocarpus (DC.) Guill & Perr, and Combretum hartmannianum Schweinf species. Five models for predicting crown width were tested for these two species. For each species, dbh, total height and crown width were recorded. DataFit-9 statistical package of the Oakdale Engineering was used to fit the selected models. Akaike’s information criterion (AIC), adjusted coefficient of determination (Ra2), root mean squared error (RMSE), numerical and graphical analyses of the residuals were used for evaluating the models.
The results of the study showed that, all fitted models were found to give satisfactory results with Ra2 range of 0.65 to 0.74 and RMSE of 1.12 to 1.40. The AIC values range from 114.8 for Combretum hartmannianum Schweinf and to 356.4 for Anogeissus leiocarpus (DC.) Guill & Perr. The study concluded that, the crown width could be estimated by the mean of diameter at breast height as it is easy to measure for ground-based inventory and stand structure determination. The crown width-diameter models examined in this study produced reasonably precise estimates for crown width and could be used to predict the crown width of the species under consideration. The study recommended that, Future research is needed with a greater variety of site and stand conditions in addition to a greater variety of tree sizes and ages. It should be noted that, the models used by this study were based on data collected from El-Nour Natural Forest Reserve in Blue Nile State; therefore, it should be used with caution outside this area.

published in Journal of Forest Products & Industries

  • من سمات الخطاب الدعوي في الإعلام الإسلامي

إن الإسلام مصدره الوحي من الكتاب والسنة، وفيه الثابت والمتغير فالثابت ما ورد فيه نص صريح لا يقبل التأويل إلا أن الإسلام دين في تشريعات سعة للاجتهاد فالأساليب والوسائل في الخطاب الدعوي يمكن للعلماء والدعاة التجديد فيها بما يوصل دين الله تعالى لكل البشر وبمختلف اللغات دون خروج على تعاليم وآداب الإسلام، ولهذا صنف هذا البحث لمراجعة الخطاب الدعوي وتوضيح سماته من خلال الإعلام الإسلامي والسعي لمعرفة مواطن الخلل في خطاب الدعوة المعاصر الذي انتابته بعض العلل والتباينات واختلاف الرؤى بين الدعاة. وهناك من الدعاة من يتحفظ على تقديم الدعوة عبر وسائل الاتصال الحديثة علماً بأنها من أسرع الوسائل في نشر الإسلام والتبشير به في العالمين، بل وتصف وسائل الإعلام الغربي الإسلام بالإرهاب والدعوة للتخلف، وقد نهج الباحث في هذا البحث المنهج الوصفي التحليلي أنسب المناهج لاستنباط الإيجابيات والسلبيات ومعرفة أين الخطأ من أجل تقديم العلاج وتصويب الأخطاء فمبتغي الدعاة إقناع المدعوين من مجتمع الدعوة أن الإسلام هو الدين القيم الذي يجد فيه الإنسان سعادة الدنيا والآخرة وإصحاح فهم وسلوك مجتمع الإجابة الذي أصابته جائحة أفقدته ثقافته الإسلامية والاعتزاز بدينه القيم.

published in مجلة (المنبر) تصدر عن هيئة علماء السودان

© 2016 University Of Gezira. All rights reserved | Design by Informatics Administration