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COASTAL FORESTS OF THE SAADANI NATIONAL PARK - CONSERVATION VALUES AND MANAGEMENT STRATEGIES

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COASTAL FORESTS OF THE SAADANI NATIONAL PARK - CONSERVATION VALUES AND MANAGEMENT STRATEGIES

Abstract and Figures

Twenty-four small coastal forests within the Saadani National Park have been surveyed. According to their topographic position different types have been defined, i.e., small hilltop forest on hillock, gully forest, forest patch/thicket clump, groundwater forest, gallery forest and large hilltop forest. Their floristic composition is analysed and their conservation value is outlined. The dynamics of the wooded vegetation and their main determinants are described. Furthermore, the firewood collection practices of the local communities and its impact on the vegetation are briefly assessed. Based on the findings several management strategies are suggested.
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Tanzania Wildlife Discussion Paper No. 37
Rolf D. Baldus (Ed.)
COASTAL FORESTS OF THE
SAADANI NATIONAL PARK
- CONSERVATION VALUES AND MANAGEMENT STRATEGIES -
by
Urs Bloesch and Frank Klötzli
GTZ Wildlife Programme Wildlife Division
in Tanzania Ministry of Natural Resources & Tourism
Dar es Salaam
2004
Contents
Foreword....................................................................................................................................3
Summary....................................................................................................................................4
1. Introduction...........................................................................................................................4
2. Methods..................................................................................................................................4
3. Description of coastal forest types....................................................................................... 5
3.1 Small hilltop forests on hillocks........................................................................................ 7
3.2 Gully forests.......................................................................................................................8
3.3 Forest patches and thicket clumps..................................................................................... 8
3.4 Groundwater forests.........................................................................................................10
3.5 Gallery forests..................................................................................................................11
3.6 Large hilltop forests......................................................................................................... 12
3.7 Large isolated trees.......................................................................................................... 14
4. Discussion.............................................................................................................................15
4.1Characteristics of coastal forests ......................................................................................15
4.2 Vegetation dynamics of wooded vegetation.................................................................... 16
4.3 Floral affinities amongst forest types...............................................................................19
5. Harvesting of forest products ............................................................................................19
5.1 Firewood ......................................................................................................................... 19
5.2 Timber and building poles............................................................................................... 22
5.3 Non-woody forest products..............................................................................................22
5.4 The Chapa Mangrove Forest............................................................................................22
6. Conservation values and management suggestions......................................................... 23
7. Conclusions.......................................................................................................................... 25
8. Recommendations............................................................................................................... 26
9. Acknowledgements..............................................................................................................27
10. References.......................................................................................................................... 27
11. List of Tanzania Wildlife Discussion Papers ................................................................. 29
GTZ Wildlife Programme in Tanzania
P.O. Box 1519
Dar es Salaam, Tanzania
www.wildlife-programme.gtz.de/wildlife
The Discussion Papers reflect the opinions of authors only. They may contain views that do not necessarily
correspond with the official positions of the Wildlife Division, GTZ and the editor.
2
Foreword
The major biodiversity and conservation value of Saadani National Park lies not in its
mammal populations but essentially in its vegetation, of which the coastal forests are the most
conspicuous. These coastal forests are under serious threat and are quickly disappearing along
the coast of Tanzania.
German Development Cooperation has assisted the creation of the National Park through the
Saadani Conservation and Development Programme. This support was essentially in relation
to planning, practical management, capacity building and involvement of the communities in
the buffer zones. Some ecological monitoring and collection of basic data was also
introduced and certain activities, such as a bird inventory are ongoing. The authors of this
Discussion Paper and the Zurich ETH University have a long affiliation with the Saadani-
Mkwaja Ecosystem. This paper, similar to a preceding one by them (Bloesch and Klotzli,
2003) serves as a presentation of baseline data. This study also serves the purpose to make
this knowledge, accumulated over more than two decades, available to the new managers of
Tanzania's latest national park, both now and in the years to come.
It was a particular fortune that the attention of the two researchers was drawn to the hitherto
unexplored Kwamsisi coastal forest, which without doubt will offer a few surprises once it
can be thoroughly surveyed by scientists. The forests described in this paper cannot, however
be conserved in the long run without the active involvement of the communities around the
National Park, and the communities need to see clear material benefits. The present trend to
develop tourism around Saadani by investors acquiring land from the communities and
thereafter excluding them from user rights on the land, the forests and the wildlife on it are
cause for major concern.
For a number of reasons Wildlife Management Areas (WMA) around Saadani National Park
have not yet been established during the course of the Saadani Conservation and Development
Programme. It is however promising that several villages, even in the Genda Genda area have
proposed development of WMA, which TANAPA, the Wildlife Division and GTZ have
agreed to support. To ensure a smooth development of these WMA, the villages must benefit
from tourism development, even that which has started. The present trend that investors
purchase agricultural land and build a lodge not only violates existing legislation, but also
excludes the villages from long-term tourism benefits. If WMA are established they will
require such tourist lodges to pay a rent or bed levy to the WMA even for land that was
acquired privately prior to the establishment of the WMA.
The WMA will facilitate the conservation measures and the traditional uses of trees and other
forest products as described in this study.
3
Summary
Twenty-four small coastal forests within the Saadani National Park have been surveyed.
According to their topographic position different types have been defined, i.e., small hilltop
forest on hillock, gully forest, forest patch/thicket clump, groundwater forest, gallery forest
and large hilltop forest. Their floristic composition is analysed and their conservation value is
outlined. The dynamics of the wooded vegetation and their main determinants are described.
Furthermore, the firewood collection practices of the local communities and its impact on the
vegetation are briefly assessed. Based on the findings several management strategies are
suggested.
1. Introduction
The main terrestrial vegetation types of the Saadani ecosystem and their biodiversity and
conservation values are outlined by Bloesch & Klötzli (2002). They stress in particular the
high biodiversity and the exceptional endemism of the poorly known coastal forests within the
Saadani savanna landscape. Moreover, they underline the importance of effective community
participation and the appropriate use of fire in view of a sustainable management of the area.
In this report we discuss the main findings of a field survey carried out from 27/7 8/8/2003
in order to complement our knowledge of the coastal forests. In particular the following
aspects are discussed:
- Botanical description of the different forest types and assessment of their biodiversity
values;
- Establishment of the floristic affinities between the analysed different forest types;
- Tentative description of the dynamics of the different forest types;
- Description of the conservation values of the wooded vegetation and of their main threats;
- Rapid assessment of the firewood collection practices of the local communities and its
impact on the vegetation;
- Suggestions for management strategies regarding these forests.
A more exhaustive floristic analysis and a list of all species recorded (indicating endemic
species) will be published in a scientific journal. This paper will also compare our forest data
with that of other coastal forests known from the literature, particularly the Zaraninge Forest.
2. Methods
For the biogeographical description of the study area we refer to Bloesch & Klötzli (2002). To
get a representative overview of the diversity of the coastal forests within the Saadani
National Park, 24 individual forests
1
(woodlands) were surveyed. As selection criteria we
considered their topographical position, physiognomy as well as their location (representative
distribution). The selection process was facilitated by the field knowledge of the Park
authorities, the preliminary vegetation map based on satellite images and aerial photographs
from R. Cochard and M. Tobler and also our own knowledge of the area. We visited the
Zaraninge Forest only briefly and did not conduct any detailed studies for time reasons and
1
A continuous stand of trees at least 10 m tall, their crowns interlocking (White 1983); see also Clarke (2000).
4
since Frontier-Tanzania / WWF (Mwasumbi et al. 1994, Clarke & Dickinson 1995) had
already carried out extended surveys.
One plot (relevé) with co-ordinates recorded by a Garmin 12 XL GPS (Global Positioning
Systems) was surveyed in a representative part of each forest following the method of Braun-
Blanquet (1932). Within a given plot the cover-abundance value of all species (nomenclature
according to Beentje 1994) was recorded, separately for the tree/shrub- (25 x 25m) and the
herbaceous layer (5 x 5m). The following scale was used:
5: Any number, with cover more than 75% of the reference area
4: Any number, with cover 50-75%
3: Any number, with cover 25-50%
2: Any number, with cover 5-25%
1: Numerous, but less than 5% cover, or scattered, with cover up to 5%
+: Few, with small cover
The relevés were grouped into different forest types according to their topographic position.
The dominant (cover-abundance value of at least 2 in one stand), and the common woody
species (constancy of at least 60%), are given for each forest types (having at least four
relevés). Floristic affinities between the different forest types were identified. Moreover, the
species richness is expressed using the alpha-diversity, i.e., the average total species number
per plot for each forest type.
Brief inquiries were conducted in form of informal interviews with some community
members of Saadani, Matipwili and Mbuyuni Kitopene villages about their firewood
collecting practices and the preferred species for timber and building poles.
3. Description of coastal forest types
The Saadani ecosystem is an old one (see Hawthorne 1993; Clarke & Karoma 2000) having a
rich vegetation mosaic composed of various terrestrial and aquatic ecosystems (Bloesch &
Klötzli 2002). The coastal forests are a characteristic feature of this savanna landscape
consisting of highly heterogeneous and diverse assemblages of forest types (Fig. 1, see Clarke
& Robertson 2000; Clarke et al. 2000), which renders any classification very difficult.
Hawthorne (1993) distinguished between moist and dry coastal forests and further used for a
finer classification the eco-geographical and chorological elements. Clarke & Robertson
(2000) recognise five major types of coastal forests within the eastern African coastal zone:
- Coastal dry forests including legume-dominated dry forests and mixed dry forest
- Coastal scrub including mixed scrub forest and maritime scrub forest
- Coastal Brachystegia forest
- Coastal/afromontane transitional forest
- Coastal riverine-, swamp- and groundwater forest
According to their topographical position we define 6 types of coastal forests along a typical
catena, from hilltop to valley floor, and we find the following recurrent elements of the
savanna landscape (see also Fig. 8):
- Small hilltop forests on hillocks (relevés N° 2, 5, 7, 10, 18, 22);
5
- Gully forests on variable topographical position (relevés N° 12, 19);
- Forest patches / Thicket clumps on variable slope (relevés N° 3, 4, 11, 15, 17);
- Gallery forests (8, 16, 21);
- Groundwater forests (relevés 9, 13, 20, 23); relevé 14 (Borassus aethiopum stand) not
considered for the analysis since it is incomplete;
- Large hilltop forests occurring on higher elevation at Zaraninge and Kwamsisi (relevé
24);
In addition, two almost monospecific (savanna) woodlands
2
were surveyed which will be not
further analysed in this report:
- Acacia robusta ssp. usambarensis In valley bottoms (relevés N° 6);
- Pteleopsis myrtifolia on moderate slope (relevés N° 1).
Fig. 1. The Saadani forest-savanna mosaic
Due to disturbances, in particular by humans and elephants, parts of some forests could be
considered as scrub forest (White 1983), but since their extent is small and regeneration is
quite rapidly (if there are no further disturbances), we prefer to conceive them as forests. Our
vegetation communities like those of Hawthorne (1993) and Clarke & Robertson (2000) are
descriptive and have not been defined statistically lacking sufficient data. The relevés of the
24 different coastal forests will be published in a scientific journal.
2
An open stand of trees at least 8 m tall with a canopy cover of 40% or more. The field layer is usually
dominated by grasses (White 1983) ; see also Clarke (2000).
6
3.1 Small hilltop forests on hillocks
Hillocks are a common feature of the Saadani National Park. Usually their top and the upper
part of the slopes are covered with low forests composed of mostly gnarled trees. This forest
type usually extends over 1 to 5 ha often having gaps due to elephants. Hilltop forests have the
driest substrate of all coastal forests. Almost each small hilltop forest has its own dominant
species as shown in Table 1 below.
Fig. 2. Small hilltop forest at Mkwaja North
Table 1. Vegetation characteristics
7
Aspect Tree layer Shrub layer Herb layer
Stand structure
Height
Cover
8 – 16 (25) m
30 – 60 %
0.3 – 3 m
10 –35 %
0 – 0.3 m
<1 – 10 %
Alpha-diversity
29 species
Dominant species
Albizia anthelmintica
Albizia petersiana
Apodytes dimidiata
Diospyros consolatae
Diospyros cornii
Diospyros kirkii
Drypetes reticulata
Haplocoelum foliolosum
Julbernardia magnistipulata
Manilkara mochisia
Manilkara sulcata
Margaritaria discoidea
Monanthotaxis buchananii
Pteleopsis myrtifolia
Rapanea sp.
Rhoicissus revoilii
Salvadora persica
Tamarindus indica
Aïdia micrantha
Canthium mombazense
Combretum holstii
Drypetes reticulata
Haplocoelum inoploeum
Hypoestes forskalei
Gutenbergia sp.
Julbernardia magnistipulata
Monanthotaxis buchananii
Polysphaeria parvifolia
Suregada zanzibarensis
Trilepisium madagascariens.
Oplismenus compositus
Common species
Aïdia micrantha, Canthium mombazense, Manilkara sulcata
3.2 Gully forests
Gully forests are usually found in the Saadani National Park as narrow belts along seasonal
drainage courses on moderate slopes on undulating or dissected topography. The forest
canopy encloses entirely the seasonal drainage course (usually less than 3 meters wide). These
small gullies are moister than surrounding slopes and ridge tops, since the collection of both
surface and groundwater provides an additional moisture supply. In some cases, the gully
forests expand over several gullies at their upper most part but their overall size does not
exceed a few hectares. The canopy is continuous like that of the gallery forests along seasonal
water courses which leads to a very sparse herb layer. The species composition of gully forests
barely differs from forest patches. Following floristic criteria, it seems that the distinction of
gully forest as own forest type is not justified.
Table 2. Vegetation characteristics
Aspect Tree layer Shrub layer Herb layer
Stand structure
Height
Cover
12 – 16 (20) m
30 – 50 %
0.3 – 3 m
25 – 30 %
0 – 0.3 m
<1 %
Alpha-diversity
24 species
Dominant species
Deinbollia borbonica
Diospyros cornii
Manilkara mochisia
Manilkara sulcata
Ochna holtii
Asteranthe asterias
Canthium mombazense
Carissa tetramera
Hunteria zeylanica
Manilkara mochisis
Uvariodendron kirkii
3.3 Forest patches and thicket clumps
8
In this study only larger forest formations, i.e. forest patches have been surveyed. This forest
type of very variable size occurs on different slopes having a highly heterogeneous stand
structure. Hilltop forests and forest patches have relatively few dominant species in common
but nevertheless many species like e.g., Aïdia micrantha, Diospyros consolatae, Manilkara
mochisia, M. sulcata or Strychnos panganensis occur in both communities. The endemic palm
fern Encephalartos hildebrandtii is a characteristic plant of forest patches (also occurring in
one hilltop forest).
Table 3. Vegetation characteristics
Aspect Tree layer Shrub layer Herb layer
Stand structure
Height
Cover
8 – 15 (25) m
25 – 45 %
0.3 – 3 m
5 –65 %
0 – 0.3 m
<1 – 35 %
Alpha-diversity
30 species
Dominant species
Baphia kirkii
Cleistanthus schlechteri
Commiphora pteleifolia
Deinbollia borbonica
Diospyros consolatae
Drypetes reticulata
Haplocoelum foliolosum
Manilkara mochisia
Mimusops somaliensis
Salvadora persica
Scorodophloeus fischeri
Xylopia aethiopica
Asteranthe asterias
Canthium mombazense
Carissa tetramera
Croton pseudopulchellus
Diospyros consolatae
Hunteria zeylanica
Manilkara mochisia
Maytenus undata
Polysphaeria parvifolia
Scorodophloeus fischeri
Strychnos panganensis
Suregada zanzibarensis
Teclea simplicifolia
Uvariodendron kirkii
Canthium mombazense
Oplismenus compositus
Scorodophloeus fischeri
Common species
Hunteria zeylanica, Manilkara sulcata, Strychnos panganensis, Uvariodendron kirkii
9
Fig. 3. Forest patch at Mkwaja North
3.4 Groundwater forests
Groundwater forests may occur on permeable sandy silt valley bottoms with a high
groundwater table. On sandy, well-drained soils almost monospecific stands of the African fan
palm (Borassus aethiopum) are frequent. Groundwater forests and gallery forests are in
practice difficult to separate, since areas of gallery forests are effectively groundwater forests
not having direct contact with river water. Consequently many of their species are common, as
e.g. Sorindeia madagascariensis which we found only in these two plant communities.
Groundwater forests have the highest biodiversity of all forest types with 35 species per relevé
in average.
Table 4. Vegetation characteristics
Aspect Tree layer Shrub layer Herb layer
Stand structure
Height
Cover
10 – 16 (25) m
40 – 75 %
0.3 – 3 m
10 –30 %
0 – 0.3 m
<1 – 40 %
Alpha-diversity
35 species
Dominant species
Celtis philippensis
Cleistanthus schlechteri
Diospyros consolatae
Hymenaea verrucosa
Julbernardia magnistipulata
Manilkara sulcata
Sorindeia madagascariensis
Strychnos panganensis
Tamarindus indica
Aïdia micrantha
Canthium mombazense
Combretum holstii
Diospyros kirkii
Erythroxylum fischeri
Euclea natalensis
Haplocoelum foliolosum
Nesogordonia holtzii
Ochna holtzii
Sorindeia madagascariensis
Syzygium sp.
Teclea simplicifolia
Achiranthes aspera
Combretum holstii
Crossandra pungens
Ochna holtzii
Oplismenus compositus
Common species
Aïdia micrantha, Polysphaeria parvifolia, Haplocoelum foliolosum
10
Fig. 4. Borassus stand along the Sima River
3.5 Gallery forests
Gallery forests are found along watercourses in flat areas. Except for the Wami River, which
flows along the southern border of the Park, and at the source in the Kwamsisi Forest all other
watercourses are seasonal. Similar to gully forests, usually a narrow band of trees and shrubs
(about 10 to 20 metres wide) encloses entirely the seasonal watercourse leading to a better
water supply (see gully forests). Relevés were taken at Msangazi (N° 8), Sima (16) and
Kombe River (21). The plots were strictly located on the river talus only to avoid recording
plants from the ecotone of the surrounding savannas on flat area.
The structure and the floristic composition of these narrow forests are highly variable
depending on the characteristics of the riverbed and its talus. The talus is usually between 2
and 5 (8) m high having mostly a steep slope angle of up to more than 100%. The stand height
is about 20 m with a low tree canopy density. Exceptionally, some tree specimen may reach a
height of up to 25 m. Locally, the shrub layer may be very dense. Each gallery forest has its
specific species composition. The dominant woody species Acridocarpus zanzibaricus,
Antidesma venosum, Cynometra suahelensis, Garcinia buchananii and Ficus sycomorus,
occur only in this type of forest. Further characteristic woody species are Baphia kirkii and
11
Polysphaeria braunii. Only few seedlings (e.g. Strychnos henningsii), which germinated after
the last rainy season occasionally root in the riverbed.
Table 5. Vegetation characteristics
Aspect Tree layer Shrub layer Herb layer
Stand structure
Height
Cover
10 – 16 (25) m
40 – 75 %
0.3 – 3 m
10 –30 %
0 – 0.3 m
<1 – 40 %
Alpha-diversity
35 species
Dominant species
Acacia robusta ssp. usambar.
Antidesma venosum
Baphia kirkii
Cynometra suahelensis
Ficus sycomorus
Garcinia buchananii
Manilkara sansibarensis
Sorindeia madagascariensis
Strychnos panganensis
Stuhlmannia moavi
Acridocarpus zanzibaricus
Baphia kirkii
Hunteria zeylanica
Ochna holtzii
Polysphaeria braunii
Polysphaeria multiflora
Stuhlmannia moavi
Panicum trichocladum
Fig. 5. Msangazi gallery forest (Mkwaja North)
3.6 Large hilltop forests
This type of forest occurs at higher elevations (often on plateaux) than the other forest types.
As outlined, no detailed vegetation survey has been carried out in the Zaraninge Forest.
12
Thanks to the personal knowledge of the Park Warden we discovered (just on our last day of
the fieldwork) about 10 km south of Kwamsisi village an unknown large coastal forest of
several square kilometres which was not yet surveyed. The forest stretches over several hills,
between about 100 and 200 m a.s.l. The site conditions of this forest are highly heterogeneous
due to the very variable relief.
Due to its more westward location the area has most probably a higher annual rainfall than
areas closer to the sea (see Bloesch & Klötzli 2002). Only the smaller part of this forest
around a permanent water source is proposed to be included in the National Park (Kwamsisi
extension). The source would fulfil an important function as water supply for animals during
the dry season. The Park Authorities are planing to construct a game post just uphill of the
source. The larger part of the Kwamsisi Coastal Forest is on open land.
We were able to survey only one vegetation plot (relevé 24) during our mission due to
time constraints. The biodiversity is relatively low with 23 species. The dominant species of
the tree layer are Haplocoeulum foliolosum and Stuhlmannia moavi while Cola microcarpa,
Combretum sp. and Diospyros consolatae dominate the understorey. Characteristic are further
many succulent plants like Aloe sp. or Sansevieria sp. and the endemic Zamiaculcas
zamiifolia (Araceae).
Kwamsisi has also a certain potential for eco-tourism due to the scenic value of the dissected
landscape. The higher elevation of Kwamsisi offers a nice view on the savanna landscape
which stretches towards the Indian Ocean.
According to Sheil (1992) coastal forests on raised ground like those from Zaraninge and
Kwamsisi were not flooded during Pleistocene sea-level changes (see also Clarke & Burgess
2000) and may have existed since the late Cretaceous. It is therefore believed that these
ancient forests have a high proportion of single site endemics. A thorough survey of the entire
Kwamsisi Forest will most likely show that this forest has a high conservation value equal to
the relatively well-known Zaraninge Forest.
13
Fig. 6. Kwamsisi Forest
3.7 Large isolated trees
Some large conspicuous isolated trees are a further feature of the Saadani ecosystem. For
instance, the grotesquely voluminous baobab (Adansonia digitata) northwest of Mbuyuni
village, gnarled huge oak-like Mimusops somaliensis or Tamarindus indica dominating a
thicket clump or pale yellow erect boles of Sterculia appendiculata trees, emerging above the
surrounding vegetation highly contribute to the attractiveness of the savanna landscape.
14
Fig. 7. Sterculia appendiculata near Mkalamu
4. Discussion
4.1Characteristics of coastal forests
Coastal forests in the Saadani ecosystem are highly variable in size, shape and structure. There
is no distinct stratification below the canopy. Coastal forests are classified as dry evergreen
forests because the great majority of the woody plants are evergreen
3
and they have to endure
a distinct dry season. The periodical dryness of these sites is further enhanced by the high sand
content of the substrate. Savannas to the contrary, have mainly deciduous
4
woody plants.
The species richness of our studied forests varies between 23 (Kwamsisi) and 35 species
(Groundwater forest). Understorey species are more diverse than canopy species. Especially in
thinner parts of the forest there is a rich community of smaller trees (5 8 m), shrubs (1 5
m) and lianas. The margins are mainly composed of often scandent armed shrubs and of lianas
which are thickly interlaced what almost impedes any penetration. The herbaceous layer is
sparse and only abundant in gaps.
Each forest has its own specific species composition although ubiquitous species are frequent.
The woody plants Aïdia micrantha, Combretum mombazense and Manilkara sulcata occur in
all forest types. Species of the plant families Caesalpiniaceae, Papilionaceae, Sapindaceae,
Sapotaceae and Rubiaceae are the major components of the canopy of coastal forests. Some
of them like Deinbollia borbonica, Manilkara sulcata or Julbernardia magnistipulata
frequently form almost monospecific stands (see also Hawthorne 1993). Legume-dominated
3
Woody plant species of which most individuals always keep more than 50% of their leaves.
4
Woody plant species of which most individuals loose at least 50% of their leaves annually at the same time.
15
coastal forests may be considered as climax, since their shrub layer is often dominated by the
same species as the tree canopy as shown in the relevés 17 and 18 (see also Clarke &
Robertson 2000).
Most coastal forests in the Saadani National Park are mixed dry forests according to Clarke &
Robertson (2000). Many of their species such as Drypetes natalensis, Lecaniodiscus
fraxinifolius, Haplocoelum foliolosum, Manilkara mochisia, Milicia excelsa or Pteleopsis
myrtifolia are geographically widespread with a wide ecological amplitude. The seeds of most
of these species are wind or animal dispersed thereby having competitive regeneration
advantage over the more slowly dispersed legume seeds (especially Caesalpinioideae, see
Clarke & Robertson 2000).
Common to all coastal forests is a high proportion of evergreen woody plants and a sharp
ecotone with the surrounding savanna. In contrast, woodlands have large continua with their
adjacent savannas. Coastal forests have a distinct floristic composition. They only share a few
common woody plants with their surrounding woodlands and savannas (excluding juvenile
thicket clumps and the ecotone domain) such as Adansonia digitata, Afzelia quanzensis,
Pteleopsis myrtifolia or Synaptolepis kirkii.
Our initial classification of forest types is not confirmed by our preliminary analysis of their
floristic species composition. Only gallery forests show a distinct species composition.
Additional relevés are necessary to refine our initial classification of small coastal forests
based on topographical criteria.
4.2 Vegetation dynamics of wooded vegetation
The dynamics of savanna landscapes are not uniform and vary considerably in space and time.
Generally, climate, soils, herbivory, fire and also termites (see Bloesch 2002) are considered
as main determinants of the tree-grass ratio. Most main determinants not only determine the
dynamics by constant impact of similar importance but often act as abrupt, short-lasting
disturbances like e.g. extreme rainfall or changes in the fire regime or changes in the patterns
of human use (such as cattle grazing or agriculture). Disturbances are strongly interactive, they
may have direct (e.g. logging) and indirect effects (e.g. browsing by elephants may open the
canopy thereby promoting grass growth which leads to an increased fire hazard) on the
vegetation physiognomy. They also influence the response of the ecosystem to future
disturbances.
In the Saadani savanna landscape, soil properties play a major role for the occurrence and
dynamics of coastal forests (see Fig. 8). The highly permeable sandy soils and the sporadic
rocky outcrops on hilltops (favours deep rooting woody plants and provides a certain fire
protection), the better water supply along seasonal water courses (including gullies) and the
high water table in well-drained valley bottoms favour woody plants at the expense of grasses.
This mainly explains the distribution pattern of hilltop, gully, groundwater and gallery forests.
Fire, the current herbivory (in particular elephants) and in part timber logging and cutting of
poles modulate primarily the physiognomy of the forest but only slightly influence their
extent.
16
Fig. 8. The occurrence and dynamics of hilltop, gully (not shown), groundwater and gallery
forests are widely a function of the soil properties favouring tree growth at the expense of
grasses and herbs. Forest patches and thicket clumps on slopes (exceptionally on flat areas),
which are irregularly distributed within a savanna matrix, however, are determined by several
interactive factors, i.e. fire, herbivory, termitaria and soil (details see text).
HF: hilltop forest TSGS: tree to grass savannas with interspersed forest patches and thicket clumps
GWF: groundwater forest GF: Gallery forest
On the other hand, the occurrence and dynamics of forest patches and thicket clumps (not
surveyed during this mission) on slopes and flat areas (permeable soil and without access to
ground water) are not directly a function of the soil properties but rather the result of a varying
combination of factors: fire regime, herbivory, termitaria and soil properties.
The genesis of thicket clumps may start with a heliophilous tree like Zanthoxylum chalybeum
often associated with a temporarily abandoned termitaria. Macrotermitinae mounds may
initiate and support the growth of thicket clumps in three ways (see Bloesch 2002):
a) Fire protection as a result of the slight elevation above the grass fires and often bare soil at
the foot-slope of the mound
b) Increased soil fertility in many cases.
c) Good soil drainage in seasonally flooded flat areas.
The stem and crown of the pioneer tree offers support to progressively invading climbers
playing an important role in the development of thicket clumps. Juvenile thicket clumps are
often composed of the shrubs (trees) Albizia petersiana, Crossopteryx febrifuga, Diospyros
17
HF
TSGS
GWF GF GWF
Main
determinants
Soil type
Soil Fire, Herbivory Termitaria, Soil Soil Soil Soil
Humic, acric to
rhodic Ferralsol
Orthic and ferric Acrisol
dystric
Planosol
dystric
Planosol
Gleysol,
Fluvisol
Current dynamics of some forest types within the Saadani National Park
zombensis, Euclea natalensis, Flacourtia indica, Flueggea virosa, Harrisonia abyssinica,
Lannea schweinfurthii, Maerua triphylla, Ochna mossambicensis, Polysphaeria parvifolia,
Uvaria kirkii and the more scandent shrubs Bridelia cathartica, Combretum constrictum,
Grewia holstii, G. sulcata, and G. bicolor. Most of these pioneer trees and shrubs are typical
savanna woody plants.
The increasing shading in the thicket clump leads to lesser grass growth, thereby reducing the
grass competition, which may favour the germination of numerous sciaphilous plants, typical
for coastal forests. They replace gradually the pioneer trees and shrubs. Usually one
sciaphilous tree (often Diospyros sp., Manilkara sp. or Tamarindus indica) acts as nucleus for
the growing thicket clump. The installation of more species in the periphery of thicket clumps
may lead to a centrifugal growing process thereby forming the often hemispheric form of
thicket clumps. The extension and regress of thicket clumps are predominately determined by
the fire regime, the grazing intensity in the surrounding savannas and the browsing intensity
(mainly elephants) within thicket clumps (in seasonally flooded areas woody plants can not
grow beyond the termitarium).
Coastal forest are mainly composed of pyrophobic species contrary to the fire-tolerant savanna
woody plants (see Bloesch 2002). Savanna fires usually only scorch their edge and do not
penetrate intact coastal forests. The low flammability of coastal forests may have the
following reasons (see also Bloesch 2002):
- The scarce herbaceous layer and the presence of some almost not flammable succulents
like Aloe spp., Euphorbia nyikae and E. tirucalli, Kalanchoe spp., Sansevieria spp., and
Sarcostemma spp. prevents any ground fire.
- The high proportion of evergreen species having in general a low flammability and
producing less litter for ground fires than do deciduous woody plants that often have
synchronised leaf fall during the dry season.
- The dense curtain at the forest edge composed mainly of scandent shrubs and lianas (e.g.
Ampelocissus spp. and Cissus spp.) of mostly low flammability hinders the penetration of
savanna fires.
In the absence of human (cutting) and elephant disturbances along the forest edge recurrent
fires enhance the sharpness of the ecotone between forests and savannas.
If there is no fire (or only of low intensity), low browsing and low cutting impact the thicket
clumps may expand to larger forest patches. We estimate, that under favourable conditions the
forest-savanna boundary line may progress at maximum 20 – 30 cm per year (see also Bloesch
2002). On the other hand, mainly intense browsing by elephants (and/or intense wood
exploitation) may reverse the process, in particular if the impact occurs along the forest edge.
Elephants may reduce the tree/shrub cover by a) breaking off large branches or even knocking
down, respectively, uprooting trees and shrubs, b) ring barking, and/or c) trampling the
understorey woody plants. As a result, light penetration may increase sufficiently to permit the
spread of grasses into the forest thereby producing enough easy flammable fuel to carry fire
from the surrounding savannas into the forests. Once forests are converted, savannas are easily
maintained since tree seedlings are not able to regenerate themselves under regular burning.
On the other hand, gaps within forests created by elephants are usually rapidly closed by
abundant natural regeneration and lateral growth of neighbouring trees and shrubs, provided
that the openings are surrounded with dense forest thereby preventing the entering of savanna
fires. Under the current fire regime (sporadic fires of mostly low intensity) and the relatively
low browsing impact by elephants, forest patches and thicket clumps tend to expand.
18
Our findings confirm that there is little evidence to assume that forests grew throughout the
Tanzanian coast in the Late Pleistocene and early Holocene (see also Bloesch & Klötzli 2002),
although their extend became greatly reduced (see 6. Conservation values and management
suggestions).
4.3 Floral affinities amongst forest types
The highly heterogeneous determinants, i.e., climate, geology, geomorphology, soils (see
Hawthorne 1993) and site specific disturbances (mainly by humans) create the very complex
mosaic of vegetation types throughout the coastal forest belt. Each single forest has its own
dynamics leading to a site-specific vegetation structure: At least 484 tree species have been
recorded in the literature to be locally dominant or common in at least one coastal forest in
eastern Africa (see Burgess & Clarke 2000, appendix 2). The similarity between and within
forest types is therefore low. The floristic affinities of coastal forests will be further analysed
in the foreseen scientific publication.
5. Harvesting of forest products
According to the terms of reference our task was limited to a brief assessment of the firewood
collection practices. Nevertheless, we also make some general comments about cutting of
timber and poles and the collection of non-woody forest products.
5.1 Firewood
The preferred firewood species in Saadani, Matipwili and Mbuyuni Kitopene villages are
listed below in Table 1. Since our survey was very brief and mainly based on the interviews
with few people the results have to be interpreted carefully. Also, for some firewood species
we got only their Swahili name without confirming it with a plant sample.
Table 1. Preferred fire wood species
Species Saadani
(24 species)
Matipwili
(8 species)
Mbuyuni Kitopene
(14 species)
19
Mbanga chuma / Olax obtusifolia
Mchaaka / Spirostachys africana
Mchala / Albizia petersiana
Mda / Diospyros zombensis
Mdaa wa bara / Euclea racemosa ssp. schimperi
Mdaa wa pwani / Avicennia marina
Mfyonzi / Lamprothamnus zanguebaricus
Mgombegombe / Sideroxylon inerme
Mhale / Strychnos sp.
Mkandaa? / Bruguiera gymnorrhiza
Mhande
Mkanga
Mkanju / Anacardium occidentale
Mkarata / Acacia hockii
Mkole / Grewia bicolor
Mkomafi (Mtonga) / Xylocarpus granatum
Mkongolo
Mkongowe
Mkoko / Rhizophora mucronata
Mkora / Grewia conocarpa
Mkulajembe / Dichrostachys cinerea
Mkunguni? / Maytenus undata
Mmgo
Mmumbu? / Lannea schweinfurthii
Mnazi / Cocos nucifera
Mn’gambu / Manilkara mochisia
Mliwaliwa
Mngongo / Sclerocarya birrea
Mpawe / Haplocoelum inoploeum
Msurugura / Olea europaea ssp. africana
Mtakawa? / Hibiscus tiliaceus
Mtutuma? / Catunaregam nilotica
Mvinje / Casuarina equisetifolia
Mwangaa / Terminalia spinosa
Myombo / different Caesalpinioideae
Mzigunga / Acacia zanzibarica
Nvelendende / Flueggea virosa
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
N.B. Mangrove species in bold
Wood is relatively abundant in the vicinity of the villages at the periphery of the Saadani
National Park and women and children only collect dead wood. Due to the abundance and
easy accessibility of firewood no firewood market exist in the Saadani area. Altogether 36
firewood species are used in the three localities. Since there is actually enough dead firewood
available the wide range of species underlines the high calorific value and the good burning
properties of many natural woody plants in the Saadani ecosystem. Species desirable as fuel
are those which burn slowly and hot, with little smoke, but it seems that the principal selection
criteria are species accessibility and ease of collection (see also Fleuret 1983).
Only five identical species are preferred in two localities and only Acacia zanzibarica and the
Red Mangrove Rhizophora mucronata are used in all three localities. Acacia zanzibarica is
the dominating species within the Park. Disturbances like overgrazing or cutting may lead to
20
vigorous encroachment by this species. Large areas around the paddocks of the former
Mkwaja cattle ranch got heavily encroached (see Walther 2002 and Tobler et al. 2003).
People from Sea Salt (about 15 km south of Saadani village) also reported an important
spreading of Acacia zanzibarica in the vicinity of the settlement since their arrival in the
eighties; this process was probably favoured by cutting. Mangroves are well known as good
firewood (and charcoal) species and they are in particular appreciated by people from the
Saadani village where coastal mangrove stands are relatively nearby.
The local people from Matipwili further listed the following species suitable for charcoal:
Mkongowe (Acacia sp.), Mkwaju (Tamarindus indica), Mtondoro (Calophyllum inophyllum?)
and Mngogi (Pteleopsis myrtifolia). Currently no charcoal production is recorded from the
area within the National Park (but see 5.4)
The daily firewood consumption is assumed to be about 2 kg per head or about 1 m
3
per year
(see De Montalembert & Clements 1983 and Bloesch 2001). The only estimate from coastal
forests from the East Usambara lowlands is 332 572 kg per person and year (Cambridge-
Tanzania Rainforest Project 1994) what seems to be too low. It seems that the actual demand
of firewood by the local population in the vicinity of the Park can be met by the use of dry
wood only.
This new National Park has a high potential for tourist development due to its coastal location
offering beach and safari tourism and its vicinity to Dar es Salaam and Tanga. Many investors
have already bought land along the beach. The demand for firewood (charcoal) for running the
tourist business and for the domestic needs of their employees and their families (probably
mostly coming from outside) is likely to increase dramatically in the near future. It is therefore
highly necessary to both assess and closely monitor the additional firewood and charcoal
demand and the supply pattern (collection areas). Also the need of firewood by salt boilers
(see Clarke & Stubblefield 1995) should be assessed. According to the expected increase in
firewood consumption the dissemination of energy saving methods (e.g. improved clay stove
instead of the traditional 3-stone stove) should be considered.
As far as we observed in the vicinity of Saadani village the local people only collect dead
firewood what does not harm the ecosystem. Currently the local people from Saadani and
Mbunyuni Kitopene villages also collect firewood in parts of the National Park. Formerly
these areas belonged to the Saadani Game Reserve and the local communities had the rights to
collect firewood. The abolition of traditional rights may cause serious problems in the
collaboration with the local communities but on the other hand, the uncontrolled entering of
people in the Park, may render the anti-poaching patrolling very difficult. A possible solution
could be the permission of collecting dead firewood within clearly defined perimeters during
fixed hours, one (two) day(s) a week.
The permission for gathering dry firewood under certain rules could also contribute to a good
collaboration with the local population and could thereby help to initiate a community-based
approach in the periphery of the Park in favour of a sustainable use of the natural resources.
We are fully aware that actually any form of collaborative management arrangement within
the National Parks in Tanzania is not allowed. Nevertheless we believe that the attribution of
limited and clearly defined rights (which are controllable) does not jeopardize the
conservation of the ecosystems within the Park but it could even improve the relationship
between the Park authorities and the local communities.
21
5.2 Timber and building poles
The relatively easy accessible coastal forests meant that they were one of the earliest sources
of timber from East Africa (see Burgess & Mbwana 2000). Along with the development and
management of Forest Reserves in Tanzania and Kenya, their most valuable timber species
were the heaviest exploited, and many forests have been exhausted of Milicia, Khaya, and
Brachylaena. Species of Hymenaea, Baphia, Afzelia and Manilkara, all present in the Saadani
National Park, have been more recently exploited, or are increasingly used now since the most
appreciated species have become unavailable (see Burgess & Mbwana 2000). Currently,
timber logging is not conceived as a major problem by the Park authorities although we
discovered fresh cutting of two Julbernardia magnistipulata trees along the Sima River, and
timber logging occasionally occurs in the Zaraninge Forest. The demand for building poles
(mainly for house construction) is high within rural communities (see Burgess et al. 2000) and
it is assumed that cutting of poles does occur in forests at the periphery of the Park.
According to our brief interviews the local population mentioned the following species
suitable for timber (Table 2).
Tables 2. Preferred species for timber
Species Saadani Matipwili
Mbamba Kofi (Mkomba or Mkongo) / Afzelia quanzensis
Mkomafi / Xylocarpus granatum (Mangrove Mahogany)
Mkula
Mninga
Mtondoro / Calophyllum inophyllum?
Mngongo / Sclerocarya birrea
Mvule / Milicia excelsa
X
X
X
X
X
X
X
X
X
X
5.3 Non-woody forest products
Coastal forests are also an important source of non-woody forest products for the rural
communities. Medicinal plants, gum copal
5
, edible plants and mushrooms, bush-meat and
wild honey play a considerable role for the subsistence mainly for poor households (see
Burgess et al. 2000). The collection of these products is not a threat (per se) to the coastal
forests provided that the exploitation respects certain rules. The use of these products may be
an incentive for the local population to better protect these forests. In view of an increased
responsibility of the local communities for natural resource management, they should have
legal access to these non-woody forest products. In the long run, the National Park should
analyse the possibility to allow the riverine population the collection of certain products (in
addition to dead wood) within the Park area.
5.4 The Chapa Mangrove Forest
We also briefly visited the Chapa Mangrove Forest along the Wami River. The following
mangrove species have been identified along a gradient of increasing flooding from land
towards the river:
5
Resin (mainly fossilised) from Hymenaea verrucosa, formerly traded to India and Arabic countries for the use
as varnish and incense (Burgess et al. 2000).
22
Avicennia marina (White Mangrove), Xylocarpus granatum (Mangrove Mahogany),
Heritiera littoralis (Moçambique Mangrove), Lumnitzera racemosa (Spring-tide Mangrove),
Ceriops tagal (Indian Mangrove), Bruguiera gymnhrorrhiza (Black Mangrove), Sonneratia
alba and Rhizophora mucronata (Red Mangrove). Most of the mangrove species are
widespread along the Indian Ocean in eastern and southern Africa. Their wood makes a good
fuel and in particular the White, Red and Indian Mangrove as well as the Mangrove
Mahogany are highly appreciated as charcoal. Furthermore, the Mangrove Mahogany and
Indian Mangrove have good timber qualities while the White, Red, Black, Spring-tide and
Moçambique Mangroves are suitable for poles. The high quality of many mangrove species
for building poles was also confirmed by the people from Mbuyuni Kitopene.
This estuarial mangrove forest was intensively exploited for timber and for charcoal by
Zanzibaris. According to our mandate, however, we did not further investigate its actual
protection state and its threats. This mangrove forest was seemingly assessed by other
organisations.
6. Conservation values and management suggestions
Between 40 million and c. 19 million years ago tropical Africa possessed a continuous belt of
forest between the East and West coasts (the ancient Pan-African forest), indicating a wet
tropical climate. The subsequent drying of the climate combined with the geological process
of uplift and rifting in central eastern Africa (completed around 10 million years ago) led to a
division of the Pan African forest into an eastern and western portion (Axelrod & Raven
1978) with a distinct evolution of forest flora and fauna. Several coastal forest species indeed
show relict or ancient lineages with the western African forest block, i.e. the Guineo-
Congolian Region (see White 1979; Burgess et al. (1998).
The combination of gradual climatic desiccation together with increasing human activity
account for much of the loss of coastal forest in East Africa during recent geological time
(Burgess et al. 1998; Clarke & Karoma 2000). People have undoubtedly influenced the
coastal ecology for millennia since the coastal region is favourable for human settlement,
cultivation and trade (Hawthorne 1993; Clarke & Karoma 2000). Nowadays the forests of the
eastern African littoral are widely recognised as high-priority biodiversity hotspots (see e.g.
Davis et al. 1994; Mittermeier et al. 1998).
Clarke et al. (2000) list 33 endemic genera and 1356 endemic species for White’s (1983)
Zanzibar-Inhambane regional mosaic/Swahilian region sensu lato (see Clarke 1998). They
estimate that further collecting and taxonomic revisions may raise this figure to 40 endemic
genera and 1500 endemic species. According to Clarke et al. (2000) the coastal forests in
eastern Africa contain 70% of the region’s endemic plant species and 91% of its endemic
genera, although they extend merely to 3170 km
2
(Burgess et al. 2000), accounting for only
about 1% of the total area. In the coastal forests there are 786 endemic species and when
divided by the 3170 km
2
of forests remaining it gives 0.25 endemic species/km
2
. For
comparison, when the 827 endemic species in the Eastern Arc mountain forests are divided by
the 9000 km
2
of forest remaining, this gives 0.092 endemic species/km
2
. Hence, in terms of
the urgency of conservation action to protect endemic species, the coastal forests may be of
higher priority for attempts to reduce the loss of forest cover, than the Eastern Arc (Burgess
2000).
23
As outlined (Bloesch & Klötzli 2002) the coastal forests are especially remarkable not only
for the many regional forest endemics (sometimes showing disjunct distribution, see Burgess
et al. 1998), but also for the fact that especially ancient lineage forests are highly dissimilar,
often containing significant numbers of single site endemics (Sheil 1992; Burgess et al. 1993;
Burgess et al. 1998; Clark & Robertson 2000; Clarke et al. 2000). Burgess (2000) reported for
Tanzania that there is a 80% difference in the vascular plant flora from sites separated by only
100 km distance.
The existence of non-forest endemic species further suggests that a forest-savanna mosaic
must have been present for a long time (i.e. long before the earliest records of forest clearance
for agriculture), to enable the necessary speciation that has taken place (Hawthorne 1993;
Clarke & Karoma 2000).
Given that severe disturbance reduces the endemic species component in coastal forests
(Mwasumbi et al. 1994), more endemic plant species probably occurred formerly in this area,
but are now extinct following the introduction of repeated fires and widespread forest
clearance by humans (see Clarke & Karoma 2000). The remaining island-like nature of the
distribution of the endemic vascular plant flora is therefore a cause of concern for the long
term viability of its rare species (Clarke et al. 2000). Regarding the resilience of coastal
forests, legume-dominated forests are the most vulnerable to fire and in particular to
clearance, since many of their Caesalpinioideae tree species require forest conditions (shaded,
high humidity microclimate) to germinate (Clarke & Robertson 2000).
It would be interesting to verify Sheil’s (1992) hypothesis about ancient and non-ancient
forests for the Saadani National Park: Ancient coastal forest (probably Zaraninge and
Kwamsisi Forest) on raised ground have single site endemics while the other much younger
forests below 100 m a.s.l. are less rich in endemic and rare species. The latter have been under
the sea at some point (most likely several times) during the past 30 million years and forests
of the lowest ground closest to the sea cannot have existed on those sites for more than ten
thousand years as such features have developed mainly since the end of the last Ice Age
(Alexander 1969; Cooke 1974).
The limited area and patchy distribution of the remaining larger coastal forests in Tanzania,
and the striking individuality of many of them, ask for a high conservation priority
(Hawthorne 1993; Burgess et al. 1998)). Two such coastal forests occur in the Saadani
National Park: Zaraninge and Kwamsisi Forest. Due to the expected high number of endemic
animals and plants of the not yet surveyed ancient Kwamsisi Forest its conservation value is
particularly high and should get the same attention as the better known Zaraninge Forest
containing four single site endemic plant species (Burgess et al. 1993). More exhaustive
biological surveys in Zaraninge Forest probably will discover additional new and rare species.
But also most of the younger and smaller forest formations, despite the assumed absence of
single site endemics, have a high biodiversity and are a significant habitat for many animals
(see Bloesch & Klötzli 2002). In addition gully and gallery forests fulfil an important function
for soil protection against erosion.
Several exotic woody plants were introduced at the former Amboni Ranch headquarters at
Mkwaja as ornamental plants. Some of them spread naturally in the surrounding vegetation,
namely the Neem tree Azadirachta indica, Senna siamea and Thevetia peruviana.
Furthermore, like all over the tropics the very invasive ruderal plant Lantana camara is
frequent. Senna siamea grows also at different places along the Mwami River, near the
Saadani nursery and together with Opuntia vulgaris at the location of the old Boma within the
24
former Saadani Game Reserve. All of these invasive plants are currently limited to the above
cited locations. It is suggested, however, to carefully monitor the situation and in case of a
further spread intervention measures have to be taken.
A thorough survey of the entire Kwamsisi Forest is highly needed in order to assess its
biological value, its current uses and threats. The landownership and traditional use rights
have also to be clarified and the interests of all stakeholders have to be assessed and necessary
protection and appropriate management techniques have to be identified with them. The
possible introduction of a collaborative and joint management in the forest area on open land,
in line with the new forestry policy (United Republic of Tanzania 1997), has to be discussed.
This approach should enable the participation of all stakeholders in the management and
conservation of this forest giving them appropriate use rights and benefits. In this regard the
long term experience of community-based wildlife conservation programmes of GTZ in
Tanzania could be useful (see Gillingham & Lee 1999; Baldus & Siege 2001).
Currently, most coastal forests within the Saadani National Park are little disturbed thereby
having a low fire hazard. Some forests, however, show openings due to elephant browsing
(also cutting along the Sima River). Fire may penetrate in these disturbed forests what may
transform them gradually into savannas. Most of the forests surveyed showed many signs of
elephant presence (fresh droppings, broken trees and twigs). Increased browsing in future due
to an expected growth of the elephant population may become a serious threat to the coastal
forests.
The expected tourist development will provoke an influx of people looking for employment in
the tourist industry. Consequently, the population number will locally greatly increase thereby
putting additional stress on the local natural resources. This immigration will render the local
communities more heterogeneous with the risk to become divided what may unable them to
cooperate internally thereby complicating any community-based natural resource
management.
As outlined by Bloesch & Klötzli (2002) the ongoing afforestation (bush encroachment) in the
savanna parts of the Saadani National Park threats its rich vegetation mosaic. It is therefore
urgent to elaborate a fire management plan to keep the savannas open. The new vegetation
map (using a recent satellite photograph of the area from January 2003) actually elaborated by
Roland Cochard will be very useful for this purpose. The current fire regime is not a serious
threat for most of the forests since they have a closed edge which does not allow the
penetration of savanna fires. Forest having encroached parts (in particular Zaraninge) should
be protected from destructive late dry season fires by fire breaks or by controlled early dry
season burning (see Bloesch & Klötzli 2002).
At the long run the conservation of the Saadani National Park will depend on the success of a
community-based management of the natural resources in the periphery of the Park (see
Barrow et al. 2000).
7. Conclusions
So far only the coastal forest of a certain extend and often on raised ground have been
investigated (mainly by Frontier-Tanzania). Our investigation showed that also small forest
formations mostly have a high biodiversity and each forest has its specific species
composition. Additional vegetation surveys are necessary to refine our preliminary
25
classification of coastal forest types and also to obtain further insight in their dynamics. These
supplementary inventories will also improve the understanding of the floristic affinities
between our defined forest types and other coastal forests known from the literature.
Small forest formations are ecologically important elements of the Saadani ecosystem. The
discovery of the unknown large coastal forest of Kwamsisi was a highlight of the mission and
a complete survey of this forest having most probably a very high conservation value is
urgently recommended. Our vegetation survey was also very useful in the rectification and
floristic definition of the vegetation units of the new vegetation map.
8. Recommendations
1. Establishment of a complete survey of the Kwamsisi Forest including:
- Preliminary mapping of the forest and calculation of its surface;
- Identification of access;
- Recognition of land ownership and traditional use rights;
- Carrying out floral and faunal inventories;
- Identification of current uses and threats;
- Protection and management suggestions; since a large part of this forest is on open land
outside the National Park, protection measures should be discussed with the local
communities.
2. Evaluate the existing information about Zaraninge Forest (from Frontier-Tanzania and the
former WWF Project) and identify the need of an additional biological survey.
3. Assessment of the age of the coastal forests within the Saadani National considering the
impact of sea-level changes during the Pleistocene. More recent shifts in the forest-
savanna mosaic could be detected using soil carbon isotopes.
4. Elaboration of a fire management plan for encroached areas and fire sensitive forests
within the Saadani National Park (see also suggestions in Bloesch & Klötzli 2002).
5. Construction of game and bird watching towers at particular scenic sites (e.g. at the edge
of the Kwamsisi Forest or in the swamp of the Zaraninge Forest) in order to increase the
tourist attraction of the area.
6. Realisation of a botanical instruction trail.
7. Assessment of a more detailed firewood survey:
a) Confirmation and complementation of the preferred firewood species;
b) Assessment of the current firewood consumption for the local communities in the
vicinity of the Park in relation to the woody production of the area;
c) Identifying the collection areas within the Park and in the areas adjacent to the Park.
d) Assessment of the need of the local communities for introducing energy saving
methods.
8. Considerations concerning the permission for dead firewood collection in the Park for the
local communities of Saadani and Mbuyuni (definition of perimeter, hours, days).
26
9. Assessment and monitoring of the firewood and charcoal demand and the supply pattern
of the Saadani area including the demand of the salt boilers and the additional demand
related to the tourist development along the beach.
9. Acknowledgements
We are grateful to the Saadani Conservation and Development Programme of Deutsche
Gesellschaft für Technische Zusammenarbeit (GTZ) for their assistance, general organization
and confidence. Our warm thanks go to the Park Warden of the Saadani National Park, Mr.
Njau, for his interest and support of the mission. Mzee Ndauka greatly assisted the realisation
of the vegetation survey thanks to his excellent field knowledge. Particular thanks go to Frank
Mbago from the Herbarium of the University of Dar es Salaam for helping in the
identification of the plant species. And finally we would like to express our gratitude to our
colleague Roland Cochard for his valuable support.
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Burgess, N.D., Dickinson, A. & Payne, N.H. (1993) Tanzanian coastal forests new
information on status and biological importance. Oryx, 27, 169-173.
Burgess, N.D., Clarke, G.P. & Rodgers W.A. (1998) Coastal forests of eastern Africa: status,
endemism patterns and their potential causes. Biological Journal of the Linnean Society, 64,
337-367.
Burgess, N.D. (2000) Global importance and patterns in the distribution of coastal forest
species. In: Burgess, N.D. & Clarke, G.P. (eds.) Coastal forests of eastern Africa, pp. 235-
248. IUCN Forest Conservation Programme. Cambridge University Press, Cambridge.
Burgess, N.D. & Clarke, G.P. (eds.) (2000) Coastal forests of eastern Africa. IUCN Forest
Conservation Programme. Cambridge University Press, Cambridge.
Burgess, N.D., Clarke, G.P., Madgwick, J., Robertson, S.A. & Dickinson, A. (2000)
Distribution and status. In: Burgess, N.D. & Clarke, G.P. (eds.) Coastal forests of eastern
Africa, pp. 71-81. IUCN Forest Conservation Programme. Cambridge University Press,
Cambridge.
Burgess, N.D., Matthews, P., Evers, Y. & Woodcock, K. (2000) Non-timber uses, threats and
local attitudes. In: Burgess, N.D. & Clarke, G.P. (eds.) Coastal forests of eastern Africa, pp.
281-302. IUCN Forest Conservation Programme. Cambridge University Press, Cambridge.
Burgess, N.D. & Mbwana, S.B. (2000) Forestry. In: Burgess, N.D. & Clarke, G.P. (eds.)
Coastal forests of eastern Africa, pp. 263-79. IUCN Forest Conservation Programme.
Cambridge University Press, Cambridge.
Cambridge-Tanzania Rainforest Project (1994) A biological and human impact survey of the
lowland forest, East Usambara Mountains, Tanzania. Bird Life Study Report No. 59. Bird
Life International, Cambridge.
Clarke, G.P. (1998) A new regional centre of endemism in Africa. In: Huxley, C.R., Lock,
J.M. & Cutler, D.F. (eds.) Chorology, taxonomy and ecology of the floras of Africa and
Madagascar, pp. 53-65. Royal Botanical Gardens, Kew.
Clarke, G.P. (2000) Defining the eastern African Coastal Forests. In: Burgess, N.D. & Clarke,
G.P. (eds.) Coastal forests of eastern Africa, pp. 9-26. IUCN Forest Conservation Programme.
Cambridge University Press, Cambridge.
Clarke, G.P. & Dickinson, A. (1995) Status reports for 11 coastal forests in Coast Region,
Tanzania. Frontier-Tanzania Technical Report No. 17. The Society for Environmental
Exploration / The University of Dar es Salaam, London and Dar es Salaam.
Clarke, G.P. & Stubblefield (1995) Status reports for 7 coastal forests in Tanga Region,
Tanzania. Frontier-Tanzania Technical Report No. 16. The Society for Environmental
Exploration / The University of Dar es Salaam, London and Dar es Salaam.
Clarke, G.P. & Karoma, N.J. (2000) History of anthropic disturbance. In: Burgess, N.D. &
Clarke, G.P. (eds.) Coastal forests of eastern Africa, pp. 251-261. IUCN Forest Conservation
Programme. Cambridge University Press, Cambridge.
Clarke, G.P. & Robertson, S.A. (2000) Vegetation communities. In: Burgess, N.D. & Clarke,
G.P. (eds.) Coastal forests of eastern Africa, pp. 83-102. IUCN Forest Conservation
Programme. Cambridge University Press, Cambridge.
Clarke, G.P., Vollesen, K. & Mwasumbi, L.B. (2000) Vascular plants. In: Burgess, N.D. &
Clarke, G.P. (eds.) Coastal forests of eastern Africa, pp. 129-147. IUCN Forest Conservation
Programme. Cambridge University Press, Cambridge.
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Cooke, H.J. (1974) The coastal geomorphology of Tanga, Tanzania. The Geographical
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Fleuret, A. (1983) Factors affecting fuelwood use in Taita, Kenya. African Studies
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Gillingham, S. & Lee, P.C. (1999) The impact of wildlife-related benefits on the conservation
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Conservation, 26, 218-228.
Hawthorne, W.J. (1993) East African coastal forest botany. In: Lovett, J.C. & Wasser, S.K.
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Conservation Priorities. Conservation Biology, 12, 516-520.
Mwasumbi, L.B., Burgess, N.D. & Clarke, G.P. (1994) Vegetation of Pande and Kiono
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107-114.
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scale vegetation patterns in a coastal savanna in Tanzania. Journal of Applied Ecology, 40,
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11. List of Tanzania Wildlife Discussion Papers
1. Baldus, R. D. (1987) Wildlife Conservation and Wildlife Management in Africa.
2. Sommerlatte, M. (1988) A Wildlife Management Plan for Communal Areas
Surroundingthe Selous Game Reserve.
3. Lerise, F. and Schüler, U. (1998) Conflicts between Wildlife and People.
29
4. Baldus, R. D. (1989) Village Participation in Wildlife Management.
5. Mitzlaff, V. U. (1989) The Situation of Women in Settlements Bordering the Selous Game
Reserve.
6. Ndunguru, F. I. (1989) Big Animals and Big Problems.
7. Rohs, W. (1989) Konzept einer ökologisch verträglichen Tourismusent-wicklung im
Norden des Selous Game Reserve-Tanzania.
8. (No author). (1990) Draft Management Plan for The Selous Game Reserve.
9. Rohs, W. (1991) The Environmental Impact Of Tourism in The Northern Selous
Game Reserve. (Translation by R. D. Baldus)
10. Lerise, F., Mwamfupe,D., Schüler. (No year)Sustainable Management of
Natural Resources in the Liwale Buffer Zone.
11.Hyera, J.M.K. (1990) Veterinary and Virological Aspects Associated with
Driving Cattle On Foot via a Stock Route Through the Selous Game
Reserve.
12.Baldus, R. D., Bigurube, G., Krischke, H., and Ndunguru, I. (1991) Community
Wildlife Management around The Selous Game Reserve.
13.(No author). (1992) Preliminary Management Plan Selous Game Reserve.
14. Hayata, R. and Kachera, I. (1992) Natural Resource Management by Self-Help
Promotion.
15. Stronach, N. (1993) Checklist of the Birds of Selous Game Reserve.
16. Baldus, R. D., Krischke, H., Lyamuya, V., and Ndunguru, I. (1994) People and
Wildlife Experience From Tanzania.
17. Baldus, R. D. and Stronach, N. (1994) Bibliography on Selous Game Reserve.
18. Kilindo, J., Ligogi, M., Magona, S., Mfaume, M., Stronach, R.H.N. (1994) A List of
Vernacular of Wild Animals of Selous Game Reserve.
19. Stronach, N. and Siege, L. (1995) The Elephant of the Selous Game Reserve and their
Management.
20.Hoffman, R. H. (1995) Land Use Conflicts and Habitat Conservation Magombera Forest
Tanzania (Red Colobus Monkey).
21. Booth, W. and Games, I. (1996) Financial Potential of the Selous Game Reserve and its
Buffer Zone.
22. Gillingham, S. (1997) Do all Peasants Farmers Look Alike? The Socio-economic Context
for Community Wildlife Management around The Selous Game Reserve, Tanzania.
23. Gillingham, S. (1998) Conservation Attitudes of Villagers Living Next to the Selous
Game Reserve.
24. Masunzu, C. (1998) Assessment of Crop Damage and Application of Non-Lethal
Deterrents for Crop-Protection East of Selous Game Reserve.
25.Hofman,R. H.,Pitra, C. and Lieckfeldt D. (1999) Phylogenetische Differenzierung von
Subpopulationen der Rappanantilope (Hippotragus Niger) In Ostrafrika.
26. Winnegge, R. (1999) An Assessment of the Water Resources in the SaadaniGame
Reserve Tanzania, and Proposals for their Development.
27. Siege, L. (2000) From Decline to Recovery. The Elephants of the Selous.
28. Baldus, R. D., Ludwig, S., Stronach, N. (2001) Bibliography on Selous Game Reserve.
29. Baldus, R. D., Hahn, D., Kaggi, S., Kaihula, Mahundi, C. C., Murphee, M.,
Roettcher, K., Siege, L. and Zacharia, M. (2001) Experiences with Community Based
Wildlife Conservation in Tanzania
30. Baldus, R. D., Broska, D., Rottcher, K. (2001) Saadani:An Introduction to Tanzania’s
Future 13
th
National Park.
31. Booth, V., Majamba, H., Nangale, G. (2002) Procedures for Communities to Enter into
Joint Ventures in WMAs.
30
32. Junge, H. (2002) Decentralisation and Community-Based Natural Resource Management
in Tanzania.
33. Bloesch, U. and Klötzli, F. (2002) The Vegetation of the Saadani National Parkand
Possible Conservation and Management Strategies.
34. Baldus, R. D., Hahn, D., Mpanduji, G.D. and Siege, L. (2003) The Selous-Nissa
Wildlife Corridor.
35. Stronach, N. (2003) Checklist of Birds of Selous Game Reserve.
36. Gastorn, G. K. (2003) The Legal Environment for Tourist Investments on Village Land
outside Wildlife Management Areas.
37. Bloesch, U. and Klötzli, K. (2004) Coastal Forests in Saadani National Park
Conservation Values and Management Strategies
38. Ngoti, P. M. and Baldus R. D. (2004) HIV/AIDS and the wildlife sector in Tanzania.
39. Ngowe, N. M. (2004) The Role of Local Communities in Wildlife Management: A Case
study of the Serengeti Regional ConservationProject.
40. Baldus, R.D. (2004) Bibliography of Saadani Game Reserve.
41. Baldus, R. D. (2004) Lion Conservation in Tanzania Leads To Serious Human Lion
Conflict. With A Case Study Of Man Eating Lions
All available Discusion Papers can be downloaded from: www.wildlife-programme.gtz.de/wildlife
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... In addition, over 40 species of fish, alongside turtles, whales, and dolphins, occur in the ocean. The park is dominated by Acacia zanzibarica and a variety of other vegetation types, including forestry-savanna-grassland mosaics, coastal forests on the Zaraninge Plateau, a shoreline with salt flats, coastal fringe forests, herbaceous vegetation, mangrove forests, and maritime ecosystems (Bloesch and Klötzli, 2004). SANAPA shares the ecosystem with Wami-Mbiki Wildlife Management Area, which is inhabited by animals such as elephants and buffalos (Syncerus caffer) (Bloesch and Klötzli, 2004). ...
... The park is dominated by Acacia zanzibarica and a variety of other vegetation types, including forestry-savanna-grassland mosaics, coastal forests on the Zaraninge Plateau, a shoreline with salt flats, coastal fringe forests, herbaceous vegetation, mangrove forests, and maritime ecosystems (Bloesch and Klötzli, 2004). SANAPA shares the ecosystem with Wami-Mbiki Wildlife Management Area, which is inhabited by animals such as elephants and buffalos (Syncerus caffer) (Bloesch and Klötzli, 2004). ...
... Les ailes des femelles atteignent à peine le premier tergite abdominal et représentent seule ment 0,24-0,28 fois la longueur du pronotum ; les denticulations de bords de la prozone sont plus fortes que chez les mâles et suffusées de noir. (BuRgeSS et al., 2003a(BuRgeSS et al., , 2003bBloeSch & Klötzli, 2004). Ensemble ils constituent le "point chaud de biodiversité de l'arc montagneux et des forêts côtières d'Afrique orientale", l'un des 25 points chauds du monde dont la conservation doit être la plus grande (MyeRS et al., 2000), et même l'un des 11 "hyperchauds" prioritaires à protéger (BRooKS et al., 2002). ...
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Le genre Afrothespis Roy, 2006, qui avait été créé d'après des femelles, est redéfini après la connaissance des mâles. Une nouvelle synonymie est établie, Afrothespis dudleyi Roy, 2006, n. syn. de A. rhodesiaca (Beier, 1973), et une espèce nouvelle est décrite, A. kenyana n. sp. Abstract. – New data on the genus Afrothespis Roy, 2006 (Dictyoptera, Mantodea). The genus Afrothespis Roy, 2006, created on females, is redefined after the knowledge of males. A new synonymy is established, Afrothespis dudleyi Roy, 2006, n. syn. for A. rhodesiaca (Beier, 1973), and a new species is described, A. kenyana n. sp.
... Tanzanian coastal forests form part of the eastern Africa coastal forests and are synonymous with the forests of White's (1983) Zanzibar-Inhambane regional mosaic , stretching as a strip from Southern Somalia through Kenya and Tanzania to Southern Mozambique (Clarke 2000). Most of the forests are small and highly fragmented , consisting of many (over 250) separate forest patches, varying in shape and structure, with their sizes ranging from 1 to 50 km 2 (Burgess et al. 2000; Bloesch & Klötzl 2004). Most of these forests are isolated from each other. ...
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The lesser pouched rat Beamys hindei is a small rodent which is patchily distributed in the Eastern Arc Mountains and coastal forests in East Africa. The ecology of this species and its current distribution in coastal forests is not well known. Therefore, we conducted a study in selected coastal forests to assess the current distribution and to determine population ecology in terms of abundance fluctuations and demographic patterns which are all inclusive for conservation. Assessments of the species distribution were conducted in five forests through trapping with Sherman live traps. Data on ecology were obtained from monthly Capture Mark Recapture (CMR) studies conducted for five consecutive nights per month in two hectares set in Zaraninge forest over a two year period. The results indicate presence of B. hindei in three forests where it was not previously recorded. The population abundance estimates ranged from one to 40 animals per month with high numbers recorded during rainy seasons. Reproduction patterns and sex ratio did not differ between months. Survival estimates were not influenced by season, and recruitment was low with growth rate estimates of one animal per month. These estimates suggest a stable population of B. hindei in Zaraninge forest. Further studies are recommended to establish the home range, diet and burrowing behavior of the species in coastal forests in East Africa. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
... Most of the park is covered by structurally diverse savanna of medium to tall grass with Hyphaene compressa, Terminalia spinosa and Vachellia (formerly Acacia) zanzibarica dominating the woody component. The savanna is interspersed with denser vegetation including thicket clumps, patches of acacia woodland, riparian forest and larger remnants of coastal forest (Burgess et al. 1998;Tobler et al. 2003;Bloesch & Klötzli 2004;Cochard & Edwards 2011). The grass layer consists of moderately tall (about 30-70 cm) grasses mixed with taller clumps (1-2 m), and with shrubs or trees (though these are absent on pockets of periodically waterlogged black clay-rich soils). ...
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We studied how grazing intensity by small and mid-sized ungulate grazers varied with nutritional quality and grass species composition in wet oligotrophic tallgrass savanna of coastal northern Tanzania. Average grazing intensity was low (3–15% by cover), and most grass species were scarcely used by herbivores. Only two grasses, Panicum infestum and Digitaria milanjiana, had nitrogen and phosphorus concentrations that were consistently above the minimum levels (e.g. nitrogen concentrations <7 mg g−1) required by the three commonest grazers, Bohor reedbuck, waterbuck and wildebeest. The best predictors of grazing intensity were cover of P. infestum (the most abundant grass, with a mean cover of 15%) and canopy height of ungrazed vegetation. Models did not contain separate predictors for nutritional quality, presumably because quality varied mainly at the grass species level and therefore was fully represented by the variable ‘cover of P. infestum’. Given that the three grazers differed greatly in body size and muzzle width (parameters known to influence nutrient requirements and the ability of grazers to feed selectively at the smallest spatial scale), we expected there to be strong resource partitioning that would be detectable in terms of grazing strategies and feeding sites. However, apart from minor differences in canopy height, greenness and diameter of grazed patches (albeit consistent with our expectations), feeding stations of the three grazers were similar and strongly dominated by P. infestum. We conclude that the low quality of herbage in wet oligotrophic savannas restricts foraging choices, which produces a characteristic yet impoverished grazing community that exhibits only limited resource partitioning.
Zaraninge Forest, part of the Coastal Forest Biodiversity Hotspot of Tanzania, is threatened by human activities. The effect of such activities on the ecology of the forest is less known. Nested quadrat sampling technique was used along preestablished transect lines. Trees had a stem density of 521 ha-1, the majority falling in Diameter at Breast Height (DBH) size classes 9.5 to 44.9 cm. There was no significant difference in species diversity between sampling areas, which had a Shannon's diversity index ranging from 1.64 to 2.63. PCA identified two vegetation sample groups with Baphia kirkii, Cynometra webberi, C. brachyrachis, Scorodophloeus fischeri and Tessmannia burttii being abundant in both groups. TWINSPAN revealed three vegetation communities: Community A was fragmented woodlands characterized by the effects of fire and exploitation and having few remaining individuals of the valuable timber trees Afzelia quanzensis and Pterocarpus angolensis; community B was growing in a moist ecologically rich habitat and included rare species (Inhambanella henriquesii), endemic species (T. burttii, C. brachyrachis and S. fischeri); and community C had dry habitats dominated by C. webberi and C. brachyrachis. We conclude that habitat characteristics, fire, past and the present exploitation clearly influence the species diversity, distribution and variation in vegetation communities. The results are discussed in context of current and future management plans for this ecologically important forest.
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A brief biogeographical description of the Saadani ecosystem is given. The terrestrial vegetation units are defined and their dominant plant species and soil types listed. The biodiversity and conservation values of the vegetation units are assessed. A transect from the sea westward towards the inland shows the typical topographic position of the vegetation units. The dynamics of the vegetation units is briefly outlined regarding mainly the impact of fire, herbivory and cutting. Based on the vegetational description of the Saadani ecosystem management suggestions are presented stressing in particular the importance of community participation and fire. In view of a sustainable management of the Saadani National Park and its surroundings additional applied research activities are proposed. A summary of the savanna research programme at the former Mkwaja cattle ranch is attached.
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Describes Mongolia's natural setting, and outlines vegetation types (alpine, mountain tundra, the patchy extension of taiga, steppe - with mountain, grassy and arid types - and desert. The vertebrate fauna comprises 130 mammal, c370 bird, 70 fish, nine reptile and seven amphibian species. Wildlife laws (the most important being the 1972 Decree on the Rational Utilisation of Natural Environment) and administration are noted. Conservation and management, including availability of resources, tie in with current stringent economic constraints. Livestock grazing is inefficient, and some rangelands are being overgrazed. Hunting, especially of wild ungulates, is also significant. Fourteen national reserves have been established, including the 5.3 million ha Great Gobi National Park.
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The coastal area around Tanga, in northeastern Tanzania, displays a variety of evidence that indicates sea levels both higher and lower than at present: raised beaches and marine-cut platforms, river terraces, aggraded valley bottoms, and a drowned valley that runs across the floor of Tanga Bay. These features are described and evidence is adduced to suggest that the sea-level changes have been eustatic and that no appreciable land movement has taken place since the Upper Pliocene.
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A reconnaissance of the tree and shrub vegetation of the coral along the Kenya coast showed a Littoral Ipomoea pes-caprae associes. The evidence suggested a Littoral Evergreen bushland climax on the sand-over-coral. The original extent of the Evergreen forest climax on the uneroded fossil coral is limited by rainfall and the degree of erosion of the coral; where rainfall is inadequate or where the coral soils are too shallow, an Evergreen bushland climax is suggested.
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