flora and fauna

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What Role Does Fire Play in Biomes?
There is a tendency to view fire as a destructive, sporadic event that is to be avoided at all cost.
While fires can be destructive, life in the subtropical scrub and woodland biome and grassland
biome has adapted particularly well to fire and is even dependent upon it. Fire has played a very
significant role in making of the African Savannah.
Negative Aspects of Fire
1. Destructive fires cause loss of human life and structures and are expensive to fight.
2. If not killed outright, wildlife are impacted by a loss of food sources.
3. Smoke and ash pollute and release greenhouse gases.
4. The intense heat can cause soil particles to become water-repellent, causing rainwater to run off
rather than infiltrate into the soil.
5. Soil erosion and flooding result from “baked” soil surfaces.
6. Fires in woodlands destroy wood that could be important for the local economy.
Benefits of fire
1. Fire plays an important ecological role by restoring nutrients to the soil. Plants benefit from the
ash.
2. Fire allows for a new cycle of successional stages to begin. Some species or plants and animals
thrive only in disturbed or burned-over areas.
3. Some species actually require intense heat to crack the seed and to allow for germination. Fire
can also cause the roots of some plants to sprout.
4. Fire kills disease and harmful insects.
5. Sporadic controlled fires prevent hotter, more destructive fires.
6. Periodic fires improve wildlife access.
Control
Humans have altered natural fire regimes. One technique to control fire is the fuel break, which
involves eliminating vegetation over a strip of land in the hope of “starving” a fire of fuel. Also
prescribed burns (an intentionally started fire) are used to reduce fuel buildup and release soil
nutrients. Prescribed burns are conducted during times when the fire will be least likely to rage out
of control.
Major types of vegetation communities in East Africa
Desert Scrub (xerophytes)
Many plants are able to survive in a desert; indeed, very few areas on Earth have no life at all.
Desert plants have adaptations to live in the heat with little water. They are short and grow far
apart from each other, so the roots of each plant can collect and store water. Many bushes grow
and flower rapidly after a rain shower. Some plants are deciduous during the dry season; others
have leaves that remain but are adapted to minimize loss of water. Plants called succulents, which
have thick bark, swollen stems, and fat leaves to store water, do well in this harsh environment.
Other plants have spines (modified leaves) and green stems to manufacture nutrients. Oases occur
where underground water comes close to the ground surface. The vegetation is more lush here,
and oases are very attractive to wildlife.
Adaptations include:
a) Water storage
Some plants can store water in their root structures, trunk structures, stems, and leaves. Water
storage in swollen parts of the plant is known as succulence. A swollen trunk or root at the ground
level of a plant is called a caudex and plants with swollen bases are called caudiciforms.
b) Production of protective molecules
Plants may secrete resins and waxes (epicuticular wax) on their surfaces, which reduce
transpiration. Examples are the heavily-scented and flammable resins (volatile organic
compounds) of some chaparral plants, such as Malosma laurina, or the chalky wax of Dudleya
pulverulenta.
Heat shock proteins (HSPs) are a major class of proteins in plants and animals which are
synthesised in cells as a response to heat stress. They help prevent protein unfolding and help refold denatured proteins. As temperature increases, the HSP protein expression also increases.
c) Evaporative cooling
Evaporative cooling via transpiration can delay the effects of heat stress on the plant. However,
transpiration is very expensive if there is water scarcity, so generally this is not a good strategy for
the plants to employ.
Line 1 represents typical mesophytic plants and line 2 represents xerophytes. The stomata of
xerophytes are nocturnal and have inverted stomatal rhythm.
d) Stomata closure
Most plants have the ability to close their stomata at the start of water stress, at least partially, to
restrict rates of transpiration. They use signals or hormones sent up from the roots and through the
transpiration stream. Since roots are the parts responsible for water searching and uptake, they can
detect the condition of dry soil. The signals sent are an early warning system - before the water
stress gets too severe, the plant will go into water-economy mode.
As compared to other plants, xerophytes have an inverted stomatal rhythm. During the day and
especially during mid-day when the sun is at its peak, most stomata of xerophytes are close. Not
only do more stomata open at night in the presence of mist or dew, the size of stomatal opening or
aperture is larger at night compared to during the day. This phenomenon was observed in
xeromorphic species of Cactaceae, Crassulaceae, and Liliaceae.
As the epidermis of the plant is covered with water barriers such as lignin and waxy cuticles, the
night opening of the stomata is the main channel for water movement for xerophytes in arid
conditions. Even when water is not scarce, the xerophytes A. Americana and pineapple plant are
found to utilise water more efficiently than mesophytes.
e) Phospholipid saturation
Have a high saturation of phospholipids in the plasma membrane which prevents the membrane
from being damaged by high temperature.
The plasma membrane of cells are made up of lipid molecules called phospholipids. These lipids
become more fluid when temperature increases. Saturated lipids are more rigid than unsaturated
ones i.e. unsaturated lipids becomes fluid more easily than saturated lipids. Plant cells undergo
biochemical changes to change their plasma membrane composition to have more saturated lipids
to sustain membrane integrity for longer in hot weather.
If the membrane integrity is compromised, there will be no effective barrier between the internal
cell environment and the outside. Not only does this mean the plant cells are susceptible to disease-
causing bacteria and mechanical attacks by herbivores, the cell could not perform its normal
processes to continue living - the cells and thus the whole plant will die.[13]
f)
Xanthopyll cycle
This is a cycle that allows dissipation of excess energy as heat during photosynthesis
Light stress can be tolerated by dissipating excess energy as heat through the xanthophyll cycle.
Violaxanthin and zeaxanthin are carotenoid molecules within the chloroplasts called
xanthophylls. Under normal conditions, violaxanthin channels light to photosynthesis. However,
high light levels promote the reversible conversion of violaxanthin to zeaxanthin. These two
molecules are photo-protective molecules.
Under high light, it is unfavourable to channel extra light into photosynthesis because excessive
light may cause damage to the plant proteins. Zeaxanthin dissociates light-channelling from the
photosynthesis reaction - light energy in the form of photons will not be transmitted into the
photosynthetic pathway anymore.
g) CAM mechanism
Plants utilising the CAM photosynthetic pathway are generally small and non-woody.
Many succulent xerophytes employ the Crassulacean acid metabolism or better known as CAM
photosynthesis. It is also dubbed the "dark" carboxylation mechanism because plants in arid
regions collect carbon dioxide at night when the stomata open, and store the gases to be used for
photosynthesis in the presence of light during the day. Although most xerophytes are quite small,
this mechanism allows a positive carbon balance in the plants to sustain life and growth. Prime
examples of plants employing the CAM mechanism are the pineapple, Agave Americana,
and Aeonium haworthii.
h) Delayed germination and growth
The surrounding humidity and moisture right before and during seed germination play an
important role in the germination regulation in arid conditions. An evolutionary strategy employed
by desert xerophytes is to reduce the rate of seed germination. By slowing the shoot growth, less
water is consumed for growth and transpiration. Thus, the seed and plant can utilise the water
available from short-lived rainfall for a much longer time compared to mesophytic plants.[6]
i)
Resurrection plants and seeds
During dry times, resurrection plants look dead, but are actually alive. Some xerophytic plants may
stop growing and go dormant, or change the allocation of the products of photosynthesis from
growing new leaves to the roots.[11][15] These plants evolved to be able to coordinately switch off
their photosynthetic mechanism without destroying the molecules involved in photosynthesis.
When water is available again, these plants would "resurrect from the dead" and resume
photosynthesis, even after they had lost more than 80% of their water content.[16] A study has found
that the sugar levels in resurrection plants increase when subjected to desiccation. This may be
associated with how they survive without sugar production via photosynthesis for a relatively long
duration.[17] Some examples of resurrection plants include the Anastatica hierochuntica plant or
more commonly known as the Rose of Jericho, as well as one of the most robust plant species in
East Africa, the Craterostigma pumilum. Seeds may be modified to require an excessive amount
of water before germinating, so as to ensure a sufficient water supply for the seedling's survival.
An example of this is the California poppy, whose seeds lie dormant during drought and then
germinate, grow, flower, and form seeds within four weeks of rainfall.
j)
Leaf wilting and abscission
If the water supply is not enough despite the employment of other water-saving strategies, the
leaves will start to collapse and wilt due to water evaporation still exceeding water supply. Leaf
loss (abscission) will be activated in more severe stress conditions. Drought deciduous plants may
drop their leaves in times of dryness.
The wilting of leaves is a reversible process, however, abscission is irreversible. Shedding leaves
is not favourable to plants because when water is available again, they would have to spend
resources to produces new leaves which are needed for photosynthesis.
(i)
Montane
The vegetation that grows on a mountain is very different from that of the surrounding lowlands.
Tall mountains intercept the movement of clouds, forcing rain to fall on their slopes. At the base
of the mountain, tall trees form an open canopy forest; the trees are able to grow here because there
is enough water and it is not too cold. The plant communities change in response to the cooler
temperatures at higher elevations. Vegetation gets shorter; the montane rain forest gives way to
bamboo forest and then open grassland with smaller trees and shrubs. Leaves are smaller and the
trunks of trees are twisted. As the air gets colder, short grasses, mosses, lichens, and other plants
replace the shrubs. Beyond a certain elevation it is too cold for any plants, except for hardy lichens,
to grow at all.
(ii)
Riparian zone
Riparian zones consist of trees, shrubs, and grasses that form along streams, creating a local
environment that is more lush with vegetation that the surrounding land. Due to the presence of
flowing water for all or part of the year, riparian zones can host a very different biome than the
surrounding region.
Riparian zones occur in many settings, such as grasslands, savannas, and various forests. They are
best expressed, however, in deserts and other arid lands, where the contrast between dry uplands
and lush valleys can be sharp. They can form even where water is not flowing but is just below the
surface. Riparian zones allow habitats for birds, shade-loving vegetation, and other organisms not
otherwise common away from the stream valley. The water and vegetation in turn attract diverse
types of animals, including frogs and other amphibians, snakes and other reptiles, and mammals,
like moose.
(iii)
Mangrove
Definitions
The term “mangrove” refers to an assemblage of tropical trees and shrubs that grows in the
intertidal zone. Mangroves include approximately 16 families and 40 to 50 species (depending on
classification). According to Tomlinson (1986), the following criteria are required for a species to
be designated a “true or strict mangrove”:
1. Complete fidelity to the mangrove environment.
2. Plays a major role in the structure of the community and has the ability to form pure stands.
3. Morphological specialization for adaptation to the habitat.
4. Physiological specialization for adaptation to their habitat.
5. Taxonomic isolation from terrestrial relatives.
Thus, mangrove is a non-taxonomic term used to describe a diverse group of plants that are all
adapted to a wet, saline habitat.
Distribution
Mangrove distribution is circumglobal with the majority of populations occurring between the
latitudes of 30° N and S (Tomlinson 1986). At one time, 75% of the world’s tropical coastlines
was dominated by mangroves. Unfortunately, mangrove extent has been significantly reduced due
to human activities in the coastal zone.
Reproductive Strategies
Mangroves have little capacity for vegetative propagation and are thus dependent on seedlings for
forest maintenance and spread. Although some species (A. germinans and L. racemosa) can
resprout from stumps (coppicing), this process is not equivalent to propagation. Mangroves exhibit
two relatively unique reproductive strategies: hydrochory and vivipary. Hydrochory (dispersal by
water) is a major means which mangrove spreads seeds, fruit, and/or propagules. Tidal action can
carry mangrove diaspores great distances from their point
of origin. Vivipary refers to the condition in which the mangrove embryo germinates while still
attached to the parent tree.
Zonation
Spatial variation in species occurrence and abundance is frequently observed across
environmental gradients in many types of ecosystems. Zonation of plant communities in intertidal
habitats is particularly striking and often results in monospecific bands of vegetation occurring
parallel to the shoreline. Although zonation patterns are usually depicted in a manner that suggests
a rigid sequence proceeding from the shoreline to upland regions, many patterns resemble a mosaic
with vegetational patterns occurring repeatedly where the land mass is interrupted by watercourses
or other variations in topography.
Ecological Significance
Most ecologists today view magroves as highly productive, ecologically important systems. Four
major roles of mangrove swamps are recognized:
1. Mangroves contribute to soil formation and help stabilize coastlines.
2. Mangroves act as filters for upland runoff.
3. Mangrove systems serve as habitat for many marine organisms such as fish, crabs,
oysters, and other invertebrates and wildlife such as birds and reptiles.
4. Mangroves produce large amounts of detritus that may contribute to productivity in
offshore waters.
In addition to these ecologically important roles, mangrove forests possess attributes that are
specifically important to humans:
1. Mangrove forests serve as protection for coastal communities against storms such as
hurricanes.
2. Mangrove forests serve as nurseries and refuge for many marine organisms that are
of commercial or sport value. Areas where widespread destruction of mangrove has
occurred usually experience a decline in fisheries.
3. Many threatened or endangered species reside in mangrove forests.
4. Mangrove forests are also important in terms of aesthetics and tourism. Many people
visit these areas for sports fishing, boating, bird watching, snorkeling, and other recreational
pursuits.
Significant eco-regions of East Africa
1. Acacia-Commiphora
Description
Location and General Description
The ecoregion forms the southern border of White’s (1983) phytogeographical classification for
the Somali-Masai Acacia-Commiphora deciduous bushland and thicket. The predominant plants
include species of Acacia, Commiphora, and Crotalaria and the grasses Themeda triandra, Setaria
incrassata, Panicum coloratum, Aristida adscencionis, Andropogon spp., and Eragrostis spp.
(McNaughton and Banyikwa 1995; White 1983). Within Tanzania, the ecoregion is bisected by
two patches of Serengeti Volcanic Grassland and patches of East African Montane Forest. The
volcanic grasslands are an integral habitat of the greater Serengeti ecosystem. However, the
grasslands are considered a separate ecoregion due to their unique grassland communities, found
only on the fine volcanic soil, or "vertisol."
The habitat transitions to miombo woodland towards the south, more Acacia-Commiphora
Bushland and Thicket towards the north, and Zanzibar-Inhambane Coastal Forest-Savanna
Mosaic towards the east. The western portion of the ecoregion is included in the greater Serengeti
ecosystem. Topographically, the ecoregion is situated on the Central African Plateau and slopes
upward from east to west. Elevation ranges from 900 m in the Speke Gulf up to 1,850 m in the Gol
Mountains. The majority of the ecoregion falls between 900 and 1,200 m.
The climate of the region is tropical with seasonal rain that falls in a bimodal pattern. The long
rains occur from March to May and the short rains from November to December. Mean rainfall is
600 to 800 mm annually through most of the region. Extremes include 500 mm in the dry
southeastern plains and 1,200 mm in the northwestern region located in Kenya. Rainfall is variable
such that the short rains may fail in a given year or rain may occur between the two rainy seasons,
thereby joining the two. Temperatures are moderate with mean maximum temperatures as high as
30°C at lower elevations and as low as 24°C at the highest parts of the ecoregion. Mean minimum
temperatures are between 9° and 18°C, and normally between 13° to 16°C.
During the long dry season (August to October), the grasslands can become extremely parched,
and many of the trees and bushes lose their leaves. Fires occur naturally in the ecosystem. Both
fire and elephant browsing play an important role in converting dense thicket and bushland into
grassland. However, a large number of fires are started by pastoralists to promote new vegetative
growth for their livestock.
The human population of the ecoregion is moderate, typically between 10 and 50 persons per km2.
The highest populations occur close to Lake Victoria and in the foothills of mountains, such as the
Pare and Usambaras, in Tanzania. Large and small commercial farms have transformed the wetter
areas, and small-holder farming is increasing in all suitable areas. Grazing by domestic livestock
occurs in the dry areas unsuitable for cultivation.
Disease is an important variable in both the pattern of human settlement and wildlife population
numbers in the region. Originally, the presence of the Tsetse fly, which carries sleeping sickness,
limited the development of much of the ecoregion. Its partial eradication has made human
settlement possible throughout much of the area. Outbreaks of rinderpest, a fatal disease affecting
ruminants, have caused periodic, large-scale mortality in both wild antelope and domestic cattle.
In 1890, 95 percent of buffalo and wildebeest in East Africa died from the disease (Sinclair 1979,
Sinclair and Arcese 1995). The continued threat of disease has resulted in conflict between
pastoralists and wildlife managers over buffer zones between protected areas and grazing lands.
Today, much of the land outside the protected area system has been converted to agricultural and
intensive-use livestock areas. Within the Serengeti ecosystem in Tanzania, local people and their
livestock utilize resources in multiple-use areas, conservation areas outside of the gazetted national
parks.
Biodiversity Features
Globally, this ecoregion has outstanding concentrations of large mammals. The Serengeti-Mara
migration of approximately 1.3 million wildebeest (Connochaetes taurinus), 200,000 plains zebra
(Equus burchelli), and 400,000 Thomson’s gazelles (Gazella thomsoni) is the most spectacular
mass movement of terrestrial animals anywhere in the world (population numbers fluctuate,
according to various sources including Campbell and Borner 1995). This migration occurs within
the southern Acacia-Commiphora bushland ecoregion for most of the year, although for part of
time the majority of the animals are found on the Serengeti volcani grasslands ecoregion.
These species do not migrate in one synchronized trek; rather the migration occurs in waves in
response to the area’s seasonal rainfall, and resulting available grazing (Bell 1971). The plains
zebras arrive in an area first and begin grazing the coarse grass stalks. Wildebeests follow and
graze on the smaller grass leaves and forbs visible after the zebras consume coarse material.
Thomson’s gazelles, with their smaller mouths and higher relatively energy demands, then graze
the small, tender new shoots. During the wetter half of the year (December to June) the animals
use the short-grass plains of the Serengeti Volcanic grasslands ecoregion. During the long dry
season, the animals move northward into the grasslands, savannas and shrublands of the Southern
Acacia-Commiphora Bushland and Thicket. During the driest months (July to October), the
animals move to the extreme northern section of the ecoregion, into Kenya’s Masai Mara game
reserve (WCMC 2000). Both the distance and direction of the migration varies in relation to
fluctuations in ungulate population density and rainfall patterns. Human-wildlife conflicts often
occur when the ungulates traverse areas outside the gazetted protected areas, moving into
agricultural lands.
This richness of large mammal numbers is also reflected in the diversity of other mammals and
vertebrates. Not surprisingly the area also supports one of the highest concentrations of large
predators with approximately 7,500 spotted hyenas (Crocuta crocuta) and 2,800 lions (Panthera
leo) (Caro and Durant 1995, see also Hofer and East 1995). Leopard (Panthera pardus), cheetah
(Acinonyx jubatus), and hunting dog (Lycaon pictus) can all be found here as well. However,
despite this mammalian richness there are no strictly endemic mammals, and only three small
mammal species are regarded as nearly endemic.
Both Tarangire and Serengeti National Parks have approximately 350 to 400 recorded bird species.
The "Serengeti Plains" is an endemic bird area (Stattersfield et al. 1998), with the restricted range
species rufous-tailed weaver (Histurgops ruficauda) (monotypic genus), Trachyphonus usambiro,
grey-crested helmetshrike (Prionops poliolophus), Francolinus rufopictus, Fischer’s lovebird
(Agapornis fischeri), and Karamoja apalis (Apalis karamojae, VU).
The area is also rich in both reptile diversity and endemism. There are three true endemics:
Amblyodipsas dimidiata, the wedge-snouted worm lizard (Geocalamus acutus), and the Mpwapwa
wedge-snouted worm lizard (Geocalamus modestus). More than 10 species of reptile are also
regarded as near-endemic to the ecoregion. The ecoregion is also an important habitat for the
pancake tortoise (Malacochersus tornieri, VU) (Hilton-Taylor 2000).
Plant diversity is lower than elsewhere in the Somali-Masai regional center of endemism. Most
species found here have a wide distribution throughout many of the savanna woodlands of East
and southern Africa.
There are some biologically unique sites within the ecoregion. The Mkomazi Game Reserve in
northern Tanzania supports some of the driest habitats within the ecoregion and is known to
support invertebrates that are potential endemics (Coe et al. 1998).
Current Status
Areas of largely intact habitat exist throughout the ecoregion. The large number of protected areas,
encompassing approximately 20 percent of the ecoregion, provides a high degree of protection to
the habitats and the species they support. These are some of the best-managed protected areas in
Africa. There is also a sizeable portion of land protected as a multiple-use area in which both
hunting and livestock grazing are permitted, with the largest area being the Ngorongoro
Conservation Area. Today’s greater Serengeti-Mara protection system began with the
establishment of a game reserve in the southeastern portion of this ecosystem. Gradually, Tanzania
and, later, Kenya added land under protected area status until reaching the current protected system
around 1967. This ecoregion includes portions or all of the following protected areas: Masai Mara
National Reserve, Ruma and Ndere Island National Parks in Kenya, part of the Serengeti (some in
another ecoregion), Tarangire, Ruaha N.P.s and Maswa, Mkomazi Game Reserves in Tanzania.
Ruaha National Park in the southernmost portion of the ecoregion is almost as large as the
Serengeti National Park. Ruaha is a connecting point between the southern Acacia-Commiphora
Bushland and thicket and the Central Zambezian Miombo woodland. The Ruaha-Rungwa
ecosystem has the second largest population of elephants in Tanzania (approximately 40,000)
(Barnes et al. 1998).
Types and Severity of Threats
There are three major types of threats to the long-term viability of the ecoregion’s flora and fauna:
(1) loss of viable corridors between protected areas; (2) increased negative interactions between
pastoralists and wildlife; and (3) unsustainable killing of wildlife. The last threat includes poaching
for bushmeat, poaching for valuable body parts, and some instances of poorly regulated and
managed game hunting concessions (permitted only in Tanzania).
While the ecoregion has large blocks of protected areas, these parks and reserves are increasingly
becoming isolated islands. Loss of viable corridors between the areas (especially the smaller
reserves) affects seasonal and drought-related movements as well as the natural migrations of
species. The smallest isolated reserves are under the most threat. Expansion of the human
population into the remaining habitats outside protected areas, and the increase of dryland
agriculture (e.g. for tobacco) could also have a major effect on the habitat. Tobacco is a particular
problem as it not only needs space for growing, but also requires fuel wood for drying. Even in the
larger blocks of protected areas, competing demands between wildlife and burgeoning human
populations near the borders is leading to increased conflict for resources and space.
Charcoal is made from many of the woodland tree species and is heavily used for daily cooking
needs as well as for drying tobacco. The cutting of woody materials for firewood and charcoal
production threatens almost all areas that have any type of human settlement. Tree regeneration is
commonly very low in densely populated areas. Woodland removal results in loss of many of the
small ungulate species as well as birds, reptiles and small mammals. Illegal taking of bushmeat,
both for subsistence and trade, is a growing concern (TRAFFIC 2000, Campbell and Hofer 1995).
An increasing reliance on bushmeat as a major protein source has resulted in localized depletions
of many wildlife species, especially in areas adjacent to protected areas.
One of the largest problems associated with the growing human population is the bushmeat trade.
Subsistence hunting for meat has been a part of the ecosystem since early hominid evolution.
However, increasing markets for bushmeat for both rural and urban people is leading to the
depletion of several antelope species. This problem is most severe in the areas outside and adjacent
to the protected sites (Campbell and Hofer 1995). Hunting and taking of bushmeat is an everincreasing and serious threat to all animals throughout the ecoregion.
Uncontrolled trophy hunting within some of the Tanzanian hunting concessions may be a problem.
Quota-setting and enforcement need to be carried out over an ecoregion scale, rather than by
individual hunting blocks. Illegal trophy hunting and poaching are not currently large problems,
partly because most black rhinoceros have been already been killed. Careful monitoring and
patrolling activities need to be continued, however, to protect the large elephant populations and
the few remaining black rhinoceros.
2. Miombo Woodlands
The name miombo is used in a number of Bantu languages in the region such
as Swahili, Shona and Bemba. In Bemba, the word "miombo" is the plural of the word "muombo",
which is the specific name for the species Brachystegia longifolia.
Miombo woodland is classified in the tropical and subtropical grasslands, savannas, and
shrublands biome (in the World Wildlife Fund scheme). The biome includes four
woodland savanna ecoregions characterized by the predominant presence of miombo species, with
a range of climates from humid to semi-arid, and tropical to subtropical or even temperate.
Miombo woodlands form a broad belt across south-central Africa, running from Angola in the
west to Tanzania to the east. These woodlands are dominated by trees of
subfamily Caesalpinioideae, particularly miombo (Brachystegia), Julbernardia and Isoberlinia,
which are rarely found outside miombo woodlands. The four ecoregions are:




Angolan miombo woodlands (Angola)
Central Zambezian miombo woodlands (Angola, Burundi, Democratic Republic of the
Congo, Malawi, Tanzania, Zambia)
Eastern miombo woodlands (Mozambique, Tanzania)
Southern miombo woodlands (Malawi, Mozambique, southern Zambia, Zimbabwe)
Moreover miombo woodlands could be classified as dry or wet based on the per annum amount
and distribution of rainfall. Where by dry woodlands occurs in those areas receiving less than 1000
mm annual rainfall. Mostly in Zimbabwe, Central Tanzania and southern areas of Mozambique,
Malawi and Zambia. On the contrary wet woodlands whilst more than 1000 mm annual rainfall
are located in Northern Zambia, eastern Angola. central Malawi and south western Tanzania.
Characteristically the trees shed their leaves for a short period in the dry season to reduce water
loss, and produce a flush of new leaves just before the onset of the rainy season with rich gold and
red colours masking the underlying chlorophyll, reminiscent of temperate autumn colours.
Flora and fauna
Despite the relatively nutrient-poor soil, long dry season (and low rainfall in some areas) the
woodland is home to many species, including several miombo specialist endemic bird species. The
predominant tree is miombo (Brachystegia spp.). It also provides food and cover
for mammals such as the African elephant (Loxodonta africana), African wild dog (Lycaon
pictus), sable antelope (Hippotragus niger) and Lichtenstein's hartebeest (Sigmoceros
lichtensteinii).
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