JOURNAL OF FOREST PRODUCTS & INDUSTRIES, 2012, 1(2), 10-20 ISSN: 2166 10
Species Dynamics and Potential Disturbances in El Nour Natural Forest Reserve, Sudan El Mamoun H. Osman*1 and El Zein A. Idris2 1
College of Natural Resources and Environmental Studies-Department of Forestry, University of Bahri. Khartoum- Sudan E mail: elmamounosman@yahoo.co.uk Telephone: +249911347139
2
College of Natural Resources and Environmental Studies-Department of Forestry, University of Bahri. Khartoum- Sudan E mail: elzeinadam@yahoo.com Telephone: +249911270310 (Received October 20, 2012; Accepted October 31, 2012)
ď€ Abstract— Sudanese natural forests have become an easy alternative source of income to the majority of rural population, especially in the Blue Nile state, where the presence of such forests and better transportation facilities provide good encouragement. The main reasons contributing to the severe impact on the natural forests are partly due to the general economic instability in the country which could partly be related to poor returns from agricultural activities and to fluctuating weather conditions. Accordingly, and in their attempts to seek for alternative source of income, people have added to their traditional demands of house hold forest products an additional demand of charcoal mass production. Such new demand put additional impacts on these types of forests and drastically disturbs their natural dynamics. This paper aims to assess the diversity and dynamics of tree species in these natural forests and investigate the possible disturbing factors influencing forest regeneration, recovery and dynamics. The study was conducted in El Nour natural Forest reserve of the Blue Nile state, Sudan. The specific objectives were to quantify the changes in species composition and structure, assess the potential causal factors so as to maintain sustainable forest productivity. Our results have indicated that the dynamic and succession of the forest species are positively favour less than 40 % of the total species native to the forest, while the majority are struggling to survive the next few years before complete disappearance from the forest. Acacia seyal followed by Balanites aegyptiaca in the northern part of the forest, and Combretum hartmannianum in the middle of the forest were found to be the pioneer species although are heavily cut for production of firewood and charcoal. The major forces driving the disturbance of the mother trees in the forest were found to be illicit felling, while those influencing natural regeneration were overgrazing and the lengthy dry season before the next rains. Weak forest management system and lack of official wills to acknowledge and support the needed fundamental reforms were found to play their role. Moreover, the concerned local communities lack economic and other incentives to play an active role in the *Correponding author
conservation or sustainable utilisation of the forest due to lack of or insecure user rights and privileges. Index Terms— Natural Forests, Disturbance, Sustainable management
Forest
Dynamic,
I. INTRODUCTION
A
natural forest which is theoretically defined as that which has never been affected by human activity of any
kind does not exist in Sudan nowadays and may be in any other country worldwide. According to [1], even the largest and most remote wilderness areas are not immune to current worldwide effects of industrial civilization such as global warming, stratospheric ozone depletion, and long-distance transport of pollutants. As such reference [1] redefined natural forest as a forest that has evolved and reproduced itself naturally from organisms previously established, and that has not been significantly altered by human activity. The term 'disturbance' refers to events that relatively quickly change forest structure so that space and resources are released and the micro-climate is altered. In natural forests, variability in disturbance dynamics profoundly affects diversity by producing a variety of habitat types to which the native species have evolved and adapted [2] and [3].
JOURNAL OF FOREST PRODUCTS & INDUSTRIES, 2012, 1(2), 10-20 ISSN: 2166 11 Landscape dynamics are influenced by ecological and
of forest succession and economics of human-caused
socioeconomic forces that impact land ownership, use, and
disturbances [4].
management. Environmental factors and market forces, along with policy influences, interact to affect the likelihood of disturbances that may alter forest cover [4].
Forests are
subjected to both naturally occurring disturbances (wildfires, winds, insect and disease epidemics, landslides, ice storms, floods and droughts) and anthropogenic disturbances (pollution, deforestation, prevention of wildfires, global warming, alteration of natural hydro-periods (flooding), application of herbicides, introduction of exotic species, litter raking,
trampling
irrigation) [5].
and
compaction,
fertilization
and
The biggest challenge facing forest
management today is the development of strategies to adopt sustainable forest management practices in which the overall capacity of forests to provide goods and services is not diminished. Natural forests are being shaped under the influence of two broad sets of forces: human needs and environmental features and processes. Neither one of these forces stays but they are in constant state of change. These changes could sometimes have positive effects and sometimes have negative detrimental impacts, the latter being the chief causes of concern as they directly affect the forests and variously affect human wellbeing and welfare. What is most important, however, is that, with few exceptions, it is human and not nature’s agency which brings about these changes and which is responsible for their magnitude and severity. human impacts are responsible for most of the world’s secondary forests [6].
Ecologists have long recognized that disturbances and recovery processes overlap in both spatial and temporal dimensions [6] and [7]. Accordingly it might not be possible to identify clearly the nature of vegetation response to particular disturbance regimes, even if we have access to paleoecological data and historical information on land use and disturbance events [8]. It therefore very important that studies of forest dynamics must be interpreted in the context of historical patterns of human impacts as well as natural disturbance events. The relationship between land use and forest succession is complex; the type and intensity of land use, soil fertility, and the surrounding landscape matrix all strongly influence the nature and rate of successional processes [6]. Tree and other plant species in any natural forest are considered to have being evolved and adapted to the local microclimate morphological,
and
ecosystem
anatomical
and
through
a
physiological
specialized adaptive
characters and mechanisms. These may include special root systems, deciduous habits, reduced leaf size, waxy or hairy leaf and seed dormancy. Many dry forest species are adapted to fire and heavy browsing. Under normal conditions with regular rainfall pattern and less disturbance, most types of trees and other plants are widespread. With an increasingly irregular rainfall pattern and severe disturbance, the weaker trees and plants will gradually disappear, and plants that are able to withstand this harsh condition take over. On the other
Studies of forest dynamics and changes in species
hand, the disturbance of the fauna in the natural forest can
composition and structure types can be viewed from three
also bring about changes in forest tree species and
different angles: The first considers forest succession and
composition. The dispersal of fauna is likely to be
natural disturbances, with emphasis on natural forces. The
substantially altered by human occupation and extensive
second focuses on the predetermined changes based on the
periods of land use. Seed predators may be more common in
management plans which based primarily on expected
altered habitats. Wind-dispersed species may dominate
financial returns from timber management; while the third
numerically over animal-dispersed species in abandoned
one concentrates on empirical studies that combine elements
clearings, particularly in dry forest zones [8].
JOURNAL OF FOREST PRODUCTS & INDUSTRIES, 2012, 1(2), 10-20 ISSN: 2166 12 In practical terms, any abnormal activity or environmental
return from agricultural activities as a result of instability in
condition, such as drought, over-cutting, over-grazing, or
the weather conditions.
severe fire burning which causes the elimination of one
absence of proper forest management strategies and effective
species or group of species from a forest, will in due course
control measures, local people in the rural areas are openly
promote the establishment of new group of species. Such
utilizing this zero-input sector (nature gift) as easy
change in plant cover composition may have negative impacts
alternative. Traditionally, the coexistence of man and forests
in terms of economic values if they are not suitable for fodder
was in harmony as long as the demand is restricted to the
or have no timber use. However, ecologically the change
satisfaction of the local house hold of fuel wood, fruits or
could be significant in that, once established, they can
building materials. At present, natural forests are seen by
improve soil structure and stability by the binding action of
most people as business sector that does not need any
their roots, and add to the soil's organic content, so assisting
qualification and free from any investment cost (except the
the return of the disappearing plants on return of favourable
axe) or risks. As a result, the traditional demand of the local
conditions.
people around these forests has shifted from house hold needs
In general, disturbances, whether natural or not play major
to mass production of charcoal and building poles, a situation
role in determining the structure and functioning of
that drastically disturbed the natural dynamics of these
ecosystems [9], directly altering resource availability [10],
natural forests.
In these conditions, and in the
providing opportunities for recruitment of new species [11], influencing the relative competitive status of individuals [12].
The domestic uses of the forest by the local inhabitants around El Nour forest include firewood, charcoal, building
The structure of a forest stand can provide a useful indicator
poles, medicine/spiritual purposes, human food, and other
of human impact, because measures such as forest basal area
uses such as oil and fibrous material sources. However, the
and stem density have documented responses to disturbances
use of charcoal as domestic source of energy for the villagers
[13].
Mean basal area in a stand may decrease as a
is very limited; instead they utilize the product for cash
consequence of increasing disturbance pressure, whereas stem
generation to support their income. This fact is the major
density of smaller trees may increase after disturbance [14].
conflict area between the villagers and the forest authorities.
Other structural indicators, such as the number of cut trees or
In countries where humans are an integral part of the natural
coppiced individuals can also indicate degree of disturbance
environment, the inclusion of utilitarian species conservation
[15]. Forest fragmentation on the other hand, is considered to
in land-use planning and priority setting schemes could
be
provide multiple benefits, and can be utilized as indicators of
a
consequence
of
a
severe
disturbance.
Forest
fragmentation leads to reduction of total amount of forest
both ecological and socioeconomic change [13].
areas, isolation of smaller patches and habitat loss [16]. The main aims of this paper were to assess the diversity and The impacts of human on the Sudanese natural forests as an
dynamics of tree species in El Nour Natural Forest Reserve
alternative source of income are increasing especially in the
and investigate the possible disturbing factors influencing
Blue Nile state where both the presence of such forests and
forest regeneration, recovery and dynamics. The specific
transportation facilities to big markets are the major boosters.
objectives were to quantify the changes in species
The main reasons contributing to the severe impact on the
composition and structure, assess the potential and actual
natural forests are partly due to the general economic and/or
conflicts between the overall concern for the forest on the one
political instability in the country and partly due to the poor
hand and efforts to support people’s livelihood and alleviate
JOURNAL OF FOREST PRODUCTS & INDUSTRIES, 2012, 1(2), 10-20 ISSN: 2166 13 poverty of individual households, rural communities and
rainfall ranging from 300-800 mm/annum and a mean
forest authorities on the other.
maximum temperature ranging between 32 C0 to 40 C0 and mean minimum temperature between 17 C0 to 26 C0 with
II.
MATERIALS AND METHODS
20% to 80% relative humidity.
The study was carried out in El Nour Natural Forest Reserve,
The forest is surrounded by a number of villages and nomadic
Blue Nile State, 6 km southeast of Eldamazine Town, and
camps and generally falls within the route of the daily trips of
about 3 km east of El Rosaries town. The total area of the
animal movement to and from water sources provided by the
forest is about 4492 hectare distributed into 33 compartments
Blue Nile River. People living around the forest are either
The forest lies between longitudes 11o 48/
small scale farmers and/or nomads investing in animal
19// N and 11o 53/ 30// N and latitudes 34o 28/ 47// E and 34o
production. The main animal herds found in the area include
32/ 35// E (Fig. 1). The total area of the forest is about 4492.1
goats, sheep, cattle and camels.
of unequal sizes.
ha having more than 55 tree species dominated by Acacia seyal, Sterculia setigera, Balanites aegyptiaca, Anogeissus
The field phase data collection was carried out using
leocarpus, Combretum hartmannianum and Terminalia
systematic sampling procedure with circular sample plots of
brownii.
35.69 m radius at 10% sampling intensity.
Landsat TM
satellite scene of the forest was used as a base map for the delineation of the sampling lines and distribution of the systematic sample plots. The forest was divided into a total of 45 sampling lines 200 m apart.
The position of each
sampling line was identified in the field using GPS technology.
The first sample in each line was selected
randomly within the first 100 m distance from the forest boundary, and the centres of the subsequent sample plots were determined 200 m apart to the end of the line using GPS. The GPS technology was used for the purpose of reducing the total sampling cost as this phase constitutes the major cost of the whole process [17]. Within each sample plot, all the mature trees were measured for their dbh, and the largest 4 trees within any sample plot Fig. 1. El Nour Natural Forest reserve
were measured for their total height.
In addition, all the
seedlings and saplings within each sample plot were counted The topography of the Forest is generally flat with some miner depressions in the central and northern part of the forest. The forest soil is generally dark cracky-clay soil dominating the northern and north-western parts of the forest, with some alluvial patches around water recourses, sandyloam in the south-eastern parts of the forest. The climate of the forest is typically that of savannah region with an average
and recorded by species.
Mean diameter at breast height
(dbh), mean height per sample plot, basal area and volume were calculated for individual compartments, species and the whole forests for mature trees with diameter > 7 cm. Relative frequency, abundance, number of individuals and total basal area were calculated for mature trees, saplings and seedlings for all species. The socio-economic results conducted by [18]
JOURNAL OF FOREST PRODUCTS & INDUSTRIES, 2012, 1(2), 10-20 ISSN: 2166 14 in his research about the management problems of the same
timber or non-timber values known to the local communities
forest were used to support the field measurement outcomes.
as to be targeted by the expected disturbance agents. Table 1 Group I species (SS)
III. RESULTS AND DISCUSSION In this study, the analysis adopted species density, basal area, number of individuals within diameter classes, diameterheight relationships as main variables for the evaluation. The main parameters used in the analysis include relative frequency (RF) relative abundance (RA), number of individuals (N) and basal areas (BA) as major indicators of species disturbance and dynamics. The study assumes that since all species are native species
Species Acacia mellifera Acacia senegal Acacia seyal (var.) seyal Acacia seyal (var.) fistula Balanites aegyptiaca Combretum aculeatum Combretum hartmannianum Combretum micranthum Dichrostachys cinerea Ziziphus spina christi
and naturally occurring in this forest, disturbances caused by
Table 2 Group II species (RS)
environmental factors should generally affect most if not all of the species.
Accordingly, the disturbances caused by
environmental agents were not considered in depth in this study and only the anthropogenic disturbances, especially those influenced by human activities, are considered. The overall results of the sampling ended with a total of
Code AM AS AY AF BE CA CH CM DS ZS
Species Acacia Polyacantha Adansonia digitata Anogeissus leocarpus Lannea fruticosa Terminalia laxiflora Ziziphus abyssinica
Code AP AD AL LF TL ZA
16154 individual trees belong to 39 tree species divided into Table 3 Group III species (WS)
four major groups depending on the availability of the normal growth stages, namely mature trees (dbh>7cm), saplings (dbh<7cm) and seedlings (height < 1m): Group I (Table 1) include strong species (SS) that dominate the forest and represented by their natural age groups that include mature trees, saplings and seedlings.
Group II (Table 2) include
relatively strong (RS) species that presents in mature and sapling tree forms without seedlings. Group III (Table 3) include weaker species (WS) which are only found as mature trees with no saplings or seedlings. Group IV (Table 4) include species found only in seedling forms with no sapling or mature trees included in the sample, but known to exist in the forest; this group is designated as rare or new species (RN). The tree species Sterculia setigera was omitted from the analysis because it includes very large trees with very high basal areas in addition to the fact that the tree has no
Species Bosica senegalensis Combretum glutinozum Dalbergia melanoxylon Entada africana Lonchocarpus laxiflorus Maerua crassifolia Scelerocarya birrea Stereospermum kunthianum Strychnos innocua Terminalia brownii Xeromphis nilotica
Code BS CG DM EA LL MC SB SK SI TB XN
Mature trees: Table 5 presents the relative frequency, relative abundance and the total number of individuals collected in the sample for mature, saplings, and seedlings of species identified in the study. The results reveal the dominance of group I species in
JOURNAL OF FOREST PRODUCTS & INDUSTRIES, 2012, 1(2), 10-20 ISSN: 2166 15
the forest as it represents over 80%, 99%, and 99% RA values for the mature, saplings and seedlings respectively of all the sampled species. Species in this group are considered to be strong enough to withstand the prevailing disturbances in the forest. Except the three Combretum spp. (CA, CH, and CM) all the other species in this group are thorny trees, a characteristic well suited to dry environments of limited amount of rain fall and prolong hot season.
Another
important characteristic of this group is that almost all its species are considered to be the major utilitarian species in the region used for firewood and charcoal production (AY,
Table 4 Group IV species (NR)
Species Grewia tanix Rus valgaris Pterocarpus lucens Lannea migritana Ficus sycomorus Diospyrus mespiliformis Delarium micropum Cordia senegalensis Cassia arerch Acacia nubica Entada africana Maerua crassifolia
AF), fodder for animals (AM, AS, BE, ZP), building poles (CA, CH, CM, DS) and medicine (AS, CH, ZS). Table 5 Attributes of Group I species
Mature trees RF RA N AM 0.1 0.0 7 AS 6.6 3.6 582 AY 23.1 41.7 339 AF 4.1 2.1 6735 BE 13.7 7.1 1150 CA 0.1 0.0 2 CH 16.0 19.6 3166 CM 5.6 6.9 1111 DS 0.3 0.2 26 ZS 0.6 0.2 29 Total 70.2 81.4 13147 Others 29.8 18.6 3007 overall 100 100 16154
Species
Saplings RF RA N 0.25 0.11 15 20 17.7 2336 36.5 46.7 6160 7.61 4.37 576 17.9 6.76 891 0.38 0.17 22 2.54 1.23 162 0.13 0.03 4 6.72 18.4 2425 6.6 4.18 551 98.7 99.7 13142 1.3 0.3 46 100 100 13188
Seedlings RF RA N 0.6 0.9 45 9.5 5.7 290 47.1 56.8 2900 2.2 1.0 51 23.2 13.6 693 0.6 0.1 7 0.8 0.5 24 0.3 0.1 4 8.1 14.5 741 5.3 6.3 320 97.8 99.5 5075 2.2 0.5 28 100 100 5103
Table 6
Ranking of Group I mature trees attributes Species RF RA N BA AM 9 9 9 9 AS 4 5 5 5 AY 1 1 1 2 AF 6 6 6 6 BE 3 3 3 3 CA 10 10 10 10 CH 2 2 2 1 CM 5 4 4 4 DS 8 8 8 8 ZS 7 7 7 7
Code GT RV PL LM FS DM DP CS CA AN EA MC
JOURNAL OF FOREST PRODUCTS & INDUSTRIES, 2012, 1(2), 10-20 ISSN: 2166 16 Table 6 ranks the mature trees of this group according to
AY occupied the first position, followed by CH and BE, CM
their RF, RA, N and BA.
and AS respectively.
It is clear that all the species
maintain almost a constant position in all the attributes with
Fig. 2. Distribution of species in the forest
Fig. 3. Relative abundance (RA) of Acacia seyal (AY) Fig. 2 shows an increase in the number of species of trees
while others like CH, AL, LF and TB are only found at the
when moving from compartment 1 to 33.
central and south eastern parts of the forest with varying
This trend, if
interpreted in consideration to Fig. 1, reveals an increase in
degrees of RA as shown in Fig. 4 and Fig. 5.
The
this attributes towards the south and south east parts of the
distribution trend shown by the species AY in Fig. 3 could be
forest which could possibly be due to soil factors or could be
attributed mainly to the type of soil, as the species generally
due to absence of major disturbing factors.
favours cracky clay type of soil which dominating the
On the other hand tree species are found in almost all
northern parts of the forest. The same reasoning could also be
compartments of the forest but with different degrees of
valid for the other examples shown in Figures 4 and 5 where
relative abundance such as AY, AF, AS and BE (Fig. 3),
the soil in the areas of their abundance is mainly sandy loam.
JOURNAL OF FOREST PRODUCTS & INDUSTRIES, 2012, 1(2), 10-20 ISSN: 2166 17
Fig. 4. Relative abundance (RA) of Combretum micranthum (CM)
Fig. 5. Relative abundance (RA) of Combretum hartmannianum (CH) Natural regeneration Table 7 ranks the saplings of Group 1 species according to
between the number of mature trees and saplings (R2 = 0.88),
their RF, RA, N excluding BA as is not applicable for young
between mature trees and seedlings (R2 = 0.90) and between
trees. Except for DS, almost all saplings maintain the same
saplings and seedlings (R2 = 0.97).
ranking positions for different attributes. Saplings of AY, AF, BE and ZS are found all over the forests in all compartments, while those of CH are found only at the central and Sothern parts of the forest and those of DC in the north-western areas with different degrees of RA. On the other hand, saplings of CA are found in only three compartments and that of AM in only two compartments. The ranking of the seedlings shown in Table 8 has similar trend to that of sampling especially for the attributes RA and N. Only the seedlings of AY and CM species maintain the same position of their saplings, while the rest occupied different positions. However, there is positive correlation
Table 7 Ranking of Group I saplings attributes
Species AM AS AY AF BE CA CH CM DS ZS
RF 9 2 1 4 3 8 7 10 5 6
RA 9 3 1 5 4 8 7 10 2 6
N 9 3 1 5 4 8 7 10 2 6
JOURNAL OF FOREST PRODUCTS & INDUSTRIES, 2012, 1(2), 10-20 ISSN: 2166 18
Socioeconomic factors:
Table 8 Ranking of Group I seedlings attributes
Species AM AS AY AF BE CA CH CM DS ZS
RF 8 3 1 6 2 9 7 10 4 5
RA 7 5 1 6 3 9 8 10 2 4
N 7 5 1 6 3 9 8 10 2 4
According to reference [18], agriculture is a source of income for 57%, livestock production for 28% and other jobs 15% of the total population of people living around El Nour forest. However, almost all people in the area have herds of animals the type and number of which depend on the major occupation and tribal traditions of the individuals. Villagers normally own more goats with few cows for milk, while nomads own more cows or camels with sheep but few goats. Irrespective of whether the investment is in crop or animal production, these people are usually practicing small scale
As far as young growth of groups II and III species is
business just enough to satisfy their daily household needs.
concerned, the results show that the mature trees belong to
The normal practice in the prevailing economic crises in the
these two groups are found only in compartments 27 to 33.
country and the fluctuating weather conditions is to look for
For group II species, the total number of saplings identified in
alternative source of income to cover the other expenses such
the sample was very small and confined to limited number of
as school fees for the children, health insurance and other
compartment not exceeding three at maximum.
basic needs.
The indicated compartments (27- 33) are the same
Unfortunately, natural forests in the area have become the
compartment characterised by high percentage of species
easiest and only alternative to generate additional income for
(Fig, 2) and good type of soil. Thus the complete absence of
the villagers either legally through permits from the forest
seedlings and limited amount of poor saplings in these two
authorities, or illegally through illicit felling. Historically, El
groups could be attributed to something else rather than soil
Nour forest provides a lot of goods and services for the local
or environmental factors. The presence of mature trees and
people in the area that include: firewood, building poles,
absence of regeneration of the same species in the same area
traditional medicines, fruits, oil seeds, and fodder for
has a relation of some kind to the anthropogenic factors. One
animals.
possible clarification is that the closeness of these groups of compartments to the forestry camp as well as to El Nour
The provision of these goods and services in themselves does
village, where the continuous presence of forest guards
not create any conflict as long as the level of utilization is for
prevents illicit felling of trees, helps in the preservation of the
the local consumption. The area of conflict and disturbance
mother trees. On the other hand, these same compartments
to the forest is the mass production of charcoal which
are liable to heavy grazing, especially of goats, from the
technically requires fresh wood rather than dead decayed one.
household herds owned by neighboring villagers, which
The consequence of such practice, which is carried out
expected to have severe damage on young growth rather than
illegally, has resulted in the creation of a lot of gaps in the
on mature trees. The opposite scenario would also be true for
forest in abnormal diameter height relationships and diameter
compartment falling far away from the forestry camp, where
classes distribution and (Fig. 6).
the negative impact fall upon mature trees.
JOURNAL OF FOREST PRODUCTS & INDUSTRIES, 2012, 1(2), 10-20 ISSN: 2166 19
Figure. 6. Frequency of diameter class distribution The second source of disturbance to the forest is overgrazing
and other incentives to play an active role in the conservation
especially by browsing animals such as goats as they have
or sustainable utilisation of this natural forest mainly due to
very severe impact on the seedlings and saplings. Our results
lack of or insecure user rights and privileges. According to
have indicated that about 66% of the tree species in the forest
Sudan Forest Act (2002), People have the right of collecting
lack natural regeneration. However, this problem could also
dead wood, passing through the forest in the absence of other
be related partly to the long dry period from November to
alternatives and for collecting drinking water. The privileges
March which directly affects the survival rate of the young
are many such as collection of fruits, seeds, animal grazing,
regeneration in the forest. Group I type of species seem to be
building poles, etc. but under special restrictions and through
well adapted to the problem of overgrazing, drought and
official permits. The role of forest authorities is completely
occasional fires as most of them are Acacias characterized by
not clear in granting and regulating these rights and
tiny leaves, thorns, hard bark and have coppicing capability.
privileges, instead they normally play a police role which
The others such as Balanites aegyptiaca and Ziziphus spina-
could lead to serious consequences like what is going now.
christi have very hard seeds capable of withstanding those harsh conditions. In fact this characteristic and the fact that
IV. CONCLUSIONS
the fruits of these two species are very palatable for goats, has
Based on the results obtained on the basis of the sample size
become an advantage resulted in wide spread of their
used, the study has concluded that although the forest is
seedlings and saplings all over the forest.
characterized by the presence of more than fifty tree species, it lacks natural balance between different age classes. The
The main causes of conflicts in this forest is not just due to illicit tree felling or overgrazing but due to weak forest management and lack sufficient official wills to acknowledge and support the needs of the local people and to reform the mutual relationships to enable them to play their positive role. The results of [18] has indicated that individual households and local communities around El Nour forest lack economic
majority of species are only found in mature stages lacking both seedling and sapling stages, while others demonstrated a kind of imbalance in their diameter-class distribution. The presence of large forest gaps was found to encourage the growth of weeds and shrubs which attract grazing animals and/or aggravate fire damage that expected to have negatively
JOURNAL OF FOREST PRODUCTS & INDUSTRIES, 2012, 1(2), 10-20 ISSN: 2166 20
the forest were found to be illicit tree felling and overgrazing
[5] Eliana, K. B., Henry, L. G. and Mary, L. D. (2001). Plant Succession and Disturbances in the Urban Forest. University of Florida, School of Forest Resources and Conservation research series FOR93.
caused by domestic animals especially by goats. However,
[6]
effect on young regeneration. The major disturbing factors in
this same agent is found to be very important in the spread of other species in the forest. Acacia species, especially seyal, fistula, and senegal, Balanites aegyptiaca, Ziziphus spina-
Chazdon, R. L. (2008). Chance and Determinism in Tropical Forest Succession. In Carson, W. P., and Schnitzer, S. A. Editors, Tropical forest community ecology. Wiley-lackwell Pp 384-405.
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christi and Combretum species were found to be the most strongest species that adapted to withstand the prevailing conditions and expected to dominate the forest in the near feature. The extent of disturbance and the distance from the village and the forest guard headquarter is positively correlated in case of illicit felling was and negatively correlated of overgrazing. The combined effect of poor forest management, weak observance of the rule of law, the incentive to play active role in forest resources conservation, and the inability of local people to gain recognition of and defend their use rights creates a climate for conflict. As a consequence the efficiency and effectiveness of existing means and organisational structures aimed at management of natural forests are still considered to be low. REFERENCES [1] Rouvinen, S. & Kouki, J. (2008.) The natural northern European boreal forests: unifying the concepts, terminologies, and their application. Silva Fennica 42(1): 135–146.
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