"Only
at Mount Kinabalu
can
you eat breakfast in a lowland rain forest, lunch in a cloud forest,
and
enjoy dinner in a subalpine meadow!" How can that be
possible? I will explain how...
Vegetation zones
on Kinabalu are largely determined by altitude, but within the main
forest zones many variations have developed, affected by differences in
the soil, slope, availability of water and degree of exposure, e.g., a
sheltered valley will have taller, more luxuriant vegetation compared
to an exposed ridge at the same altitude.
Lowland
dipterocarp forest
My wife with the background of
lowland dipterocarp forest.
Lowland dipterocarp forest
occurs mainly to the north and east, covering about 35% of
the
park. The forest canopy can reach as high as 50 meters (160 feet). It
is dark and dim and there is little ground cover. Trees in the family
Dipterocarpaceae are dominant.
These lowland
dipterocarp forests
support the highest concentrations of animal life because the stature
of the trees provides a much greater variety of habitats and food.
Dipterocarps themselves are not a main source of food.
They fruit
rarely but when they do, they fruit "en masse".
At these times, whole hillside are covered in drifts of cream, yellow
or pink from flowers or young fruits, making you realise just how
dominant the dipterocarps are in what little remains of Borneo's
undisturbed lowland forest.
The lowland
forests are also rich in
a variety of fruit trees such as durian, rambutan and Tarap, as well as
figs. Figs have been prove to be one of the most important sources of
food, especially for monkeys and civets and for larger birds such as
hornbills, barbets and pigeons. For birdwatchers it is always
worthwhile spending some time beneath a large fruiting fig, since large
mixed species feeding parties are often attracted to its abundant
fruits. While other fruits can be very seasonal, there is always a fig
fruiting somewhere.
Lower
montane oak-chestnut forest
Above about 1,200 meters (4,000
feet) the lowland trees peter out as conifers and oaks become more
dominant. The trees are smaller, the canopy reaching 25 to 30 meters
(80 to 100 feet) at most. Because of the cooler climate, peat begins to
develop and mosses become common. More light reaches the ground so
there is both a thicker ground cover and thicker development of
epiphytes, especially orchids. Other trees that are particularly common
in this montane forest are members of the eucalyptus and tea families
as well as conifers such as Dacrydium,
Podocarpus, Dacrycarpus, Agathis and Phyllocladus which
have no flowers.
Co-dominant with
the conifers are
the oaks. Borneo is at the hub of the Malesian oak kingdom, with over
100 species in the oak family Fagaceae recorded on the island. Twelve
chestnuts and almost 50 oaks occur on Kinabalu, their fruit ranging
from shiny little pixie caps sitting in a dainty cup, to stony kernels
almost covered by the thick, massive coat, except for a hole at the
top, as big as a child's fist. Fallen acorns and spiny chestnut cases
are common along the trails.
Oaks and
chestnuts are also important
source of food, not only for animals such as squirrels who can gnaw
through even the hardest kernel, but also for wild pigs. In the past,
when large tract of forest still covered Borneo, pigs formed large
herds migrating up to the oak-chestnut forest in the fruiting season.
Here they could also build 'nests' in which to give birth, taking
advantage of the abundant food.
Upper
montane/cloud forest
Above about 2,200 meters (7,200
feet), where swirling mist blanket the forest for much of the day, lies
the moss or cloud forest. Here the trees are thickly cloaked and
shawled with mosses and liveworts dripping with moisture. Orchids are
abundant, both in the ground cover and as epiphytes, and members of
rhododendron family, as well as conifers, become particularly common at
these altitudes.
It was in these forests that Sir Hugh
Low found one
of his most spectacular plants - the magnificent Low's Rhododendron,
its huge golden heads almost glowing in the misty forest.
My wife with cloud forest at the
background.
The
rhododendrons are some of Kinabalu's loveliest flowers and while
Kinabalu cannot lay claim to the vast numbers of rhododendrons as grow
in the forests of China and Nepal, 24 out of the 50 described for
Borneo grow on the mountain and five are found nowhere else.
Ultramafic soils
The underlying rock also has a strong influence on vegetation zones. In
areas where ultramafic rocks occur, the vegetation changes abruptly.
Ultramafic forests cover about 16% of the park. Here the soils are low
in phosphates and high in iron, silica and metals poisonous to many
plants. The high toxic content of these soils prevents many species
from growing in these areas, so distinct communities containing rare
and unusual species and many endemics have developed. The pitcher
plants Nephentes villosa
and N. rajah
and the slipper orchids, Paphiopedilum
rothschildianum and P.
dayanum are found only on ultramafic soils in the Kinabalu
Park.
Subalpine
meadow zone
By about 3,300
meters (11,000 feet),
a subalpine zones
has developed. The trees are gnarled and stunted,
forming a shrub community with conifers and rhododendrons dominant. The
scarlet, thimble-sized flowers of the Heath Rhododendrons (R. ericoides) grow
in thickets here together with the larger red-flowered Box-leaved
Rhododendron (R.
buxifolium)
which can be spectacular when in full bloom around March and April. In
open soggy patches, grassy meadow-like associations develop, consisting
buttercups, potentillas, eyebright and gentians, more familiar from
temperate meadows. Shrubs raspberries are common - a favourite food for
the Mountain Blackbird.
It's me, at Laban Rata resthouse
with subalpine meadow and silver black rock behind.
In cracks and
cervices in the
rocks, tough little mountain orchids find a root-hold, looking like
drifts of snow when in full bloom. The tree-line here is determined not
by altitude but by soil, or rather, by the lack of it. The fierce winds
and torrential rains make it impossible for most plants to survive
higher than about 3,700 meters (12,000 feet). In sheltered places and
in rock crevices, a few dwarf, twisted bonsai-like shrubs struggle for
life while sparse tough grasses barely survive in sheltered shallow
hollows filled with sand scoured from the surrounding granite rocks.
