Where man is the chief threat

The vital, complex ecosystem that is our forest cover is endangered by human activity. Primary jungle one-and-a-half times the area of Pahang was clear felled in just 20 years. FAEZAH ISMAIL reports.

Why save the Jungle? —come with an observant eye and the question will answer itself. — P.W. Richards, a forest ecologist

COLLINS Cobuild dictionary defines a jungle as a forest in a hot country where there is a very large number of tall trees and other plants growing very closely together.

It fails to mention, even in passing, the biological diversity of the tropical rain forest, encompassing all species of plants, animals and micro-organisms as well as the ecosystems of which they are a part.

The Malaysian jungle, along with forests in other parts of the tropics, are called Tropical Rain Forests — a term coined by A.F.W. Schimper in his classic work, Plant geography (1898, 1903), and this has generally been used ever since.

It describes the forests of the ever-wet tropics where there is no, or only minimal, seasonal water shortage, says T.C. Whitmore in his book Tropical Rain Forests of the Far East.

By now, the concern expressed by ecologists and environmental activists, both locally and abroad, that the Malaysian forest is fast shrinking in size must have been heard by almost every Malaysian.

Consider this: land covered with forests for the whole of Malaysia was reduced from 23.79 million hectares in 1970 to 18.40 million hectares in 1989 — the area lost was almost 1 1/2 times the size of Pahang.

Reduction was 31.4 per cent for Peninsular Malaysia, 29.9 per cent for Sabah and 10.5 per cent for Sarawak.

Dr N. Manokaran, a forest ecologist with the Forest Research Institute Malaysia, says almost all the areas cleared were pristine lowland forests including the wetlands — the largest reservoir of genetic variation of dipterocarp trees, the biggest and most Important timber group of the country and of the Southeast Asian region, and a storehouse of biological diversity.

Nevertheless, Malaysia’s tree cover to land mass ratio is one of the highest in the world.

Of a total land mass of 33 million hectares, 58 per cent is covered with forests (virgin plus logged-over forests) and another 14 per cent with tree crops such as rubber, oil palm, cocoa and coconut (these used to be primary forest areas).

It seems there is still a lot of undeveloped forested areas which belong to the various States. The extent is difficult to guess, say forest ecologists.

When Richards made his eloquent plea in 1970, Malaysia was already making great strides in its drive to lessen poverty. Among other measures agricultural areas expanded considerably, mainly for industrial crops especially in the peninsula.

History shows that organized land clearing activities took place in the 1840s when large-scale tin mining developed in the Larut district of Perak, near Taiping.

Long Jaafar, the Malay chief who collected taxes in Larut, has been credited with having discovered tin deposits in what was then a swampy and isolated part of Perak.

It was he who subsequently invited Chinese entrepreneurs from Penang to mine tin in the state.

Up to now, however, land opened up for mining constitutes only 113,000 hectares throughout the peninsula:

"This marked the beginning of the first significant change in forest cover," says Manokaran.

But many more areas of virgin forests were cleared when rubber plantations came onto the scene in the early 1900s.

When rubber prices in the world market plummeted, Malaysia looked to oil palm as an alternative commodity for export and more lowland primary areas had to be sacrificed.

The attractive earnings obtained from the rubber and oil palm plantations provided the impetus for the building of roads and transport facilities. More money was also pumped into the agricultural sector.

While one is compelled to accept the fact that encroachment into the virgin forest is an inevitable consequence of development, the nagging question still remains: how has man’s interference altered the status of the Malaysian forest?

Basically, the depletion of primary forests in Malaysia has been the result of two main categories of human activity:

• the degradation of virgin forests into secondary ones through uncontrolled logging and shifting cultivation.

From 1971 to 1990, primary forest conversion to non-forestry purposes intensified when Government-land development and settlement schemes were established, mainly in Peninsular Malaysia.

Estimates by Worldwide Fund for Nature (WWF) reveal that some 1.64 million hectares of lowland forests, representing nearly 20 per cent of the forested area in the peninsula, were cleared to resettle about four per cent of the population.

"The objective of alleviating poverty was achieved but at considerable environmental cost," laments a forest ecologist.

Uncontrolled logging and shifting cultivation are among several actions by man which will disturb the fragile ecosystem of a primary forest, degrading it into a secondary forest.

The disturbed area will be invaded or colonized by pioneer species such as ma-hang (Macaranga species), balik angin (Mallotus species), mendarong (Trema species), bamboo and others, which will dominate the place for some time.

If remnants of the primary species are present in the vicinity then eventually, maybe hundreds of years later, the secondary forest .will reach its climax state and become a primary forest again. However, it may not have the original biodiversity of a virgin forest.

Natural disasters such as forest fires and prolonged severe drought can also cause mortality to the climax tree species.

In addition, the primary forest could become impoverished by volcanic eruptions and cyclones, but these do not apply to Malaysia.

Minor natural disturbance in the primary rain forest such as a large canopy tree dying of old age or some trees being uprooted during a storm is part of its natural regeneration process.

Just how much of Malaysia’s primary forest has become denuded is not exactly known but Forestry Department estimates show the extent of secondary forests in the permanent forest estates of Peninsular Malaysia alone to be around 174,000 hectares, mainly due to shifting cultivation.

It is said more of such tracts can be found in State land (areas outside forest reserves) but it is not clear whether any attempt at ascertaining their range has been made.

"The problem could be serious if due care is not given during logging," concedes Dr Wan Razali Wan Mohamed, director of the institute’s Forestry Research Division. "As the country develops, more primary forest areas will be logged"

Commercially, a secondary forest has little value. This is because most of the valuable timber species can only be found in the virgin forest.

"Ecologically, one can argue that a secondary rain forest is still environment friendly," says Dr Chan Hung Tuck, director of the institute’s Environmental Science Division.

For one, it can continue to provide carbon sinks through the process of photosynthesis and help to prevent soil erosion.

Besides, small pockets of secondary forests do serve as places of refuge for wildlife.

Even so, the biological diversity in the secondary forest is many times poorer than that of the primary.

"Conservation of biodiversity in a virgin forest should not be seen purely as an academic pursuit," says Mr Ang Lai Hoe, a silviculturalist with the institute, specializing in rehabilitation of degraded land. "Why? Because it affects our daily life as well."

Among other important functions, the virgin forest is also a rich source of plants with medicinal value which have yet to be explored and a large genetic pool of fruit trees.

"Complete replacement of primary forest by secondary has drastic, regressive effects on the flora and fauna," warns Whitmore.