Travel Reference
In-Depth Information
Kerangas (Heath Forest)
Sandy soils that are highly acidic and drain
quickly support a highly specialised habitat
known as
kerangas,
an Iban word meaning
'land that cannot grow rice'. This forest type is
composed of small, densely packed trees that
seldom exceed 20m in height. Due to difficult
growing conditions, plants of the
kerangas
have developed extraordinary ways to protect their leaves from the blazing sun and ac-
quire needed minerals. Some, for example, obtain nutrients by providing a home for ant
colonies that, like tiny pizza-delivery people, bring food to the plant.
The
kerangas
is home to the world's greatest diversity of pitcher plants
(Nepenthes),
which trap insects in chambers containing enzyme-rich fluids and then digest them.
Borneo's remaining
kerangas
is increasingly restricted to protected coastal areas like
Sarawak's Bako National Park and remote mountain tops like those in Sabah's Maliau
Basin Conservation Area.
Borneo lies within what is known as the 'ever-wet
zone' - it gets at least 60mm of rain every month of
the year, with rainfall in most months averaging
about 200mm.
Lowland Dipterocarp Forest
Found up to an altitude of about 900m or 1000m, Borneo's lowland forests are dominated
by trees belonging to the dipterocarp family. More than 150 species of these magnificent
trees, which can reach a height of 60m, anchor Borneo's most ecologically important eco-
system, the lowland dipterocarp forest, which has more species of flora than any other
rainforest habitat in the world - a single hectare may shelter 240 different plant species!
Most trees in lowland dipterocarp forests
synchronise their flowering and fruiting to co-
incide with the El Niño-induced dry weather
that usually occurs every four years or so. With
so many fruits available during the same six-
week period, seed predators - gorge them-
selves though they may - are unable to devour
them all, so enough are able to germinate. In recent years however, this pattern, first de-
scribed by Prof Lisa M Curran of Yale, seems to have been disrupted.
Of the countless animals found in a dipterocarp forest, few are as flamboyantly well ad-
apted as the many types of gliding animals. In addition to birds and bats, there are frogs,
lizards, snakes, squirrels and lemurs that 'fly' between trees.
The rainforests of Borneo are exposed to twice as
much sunlight as temperate forests, but just 2%
penetrates all the way to the forest floor. That's why
so much jungle biodiversity is up in the canopy.
