Changing tropical forest landscapes: A view from a small plane

We emerge from the thick tropical clouds that perpetually hang over Kota Kinabalu at this time of year. I crane my neck to get a good view through the plane window of the surreal profile of Mount Kinabalu, its multi-pronged rocky top standing well aloof of the surrounding clouds and forest. It seems as if the mountain, aware of its own splendour, has shaken off all vegetation from its peaks to better show off their plutonic immensity. Neighbouring lesser hills are overwhelmed by forest which runs rampant up and over all ridges and tops, but not on Kinabalu. As the plane skirts round Kinabalu’s southern edge the mountain slowly recedes, as does the cloud which clings to the coast. I turn my attention to the forest below. It is unbroken, filling valleys, and rising up and over ridges. Different shades of green linger in the forest canopy — lighter on the ridges and darker in valley bottoms. A large tree catches my eye, standing proud of the forest as if emulating Kinabalu itself. The view continues unchanged for forty minutes as the plane carries me across to Sabah’s east coast. The monotony of the forest is broken only by the glint of an occasional river. My interest is suddenly rekindled by a small dirt road, a rough settlement, white rock exposed in a small quarry — shockingly bright against the dark forest — then some fields, and a plantation of some sort. Settlements now come thick and fast as the forest is dissected by small roads and tracks. The forest quickly falls away in the few minutes before touch down, and collapses into a patchwork of small fragments before giving way entirely to fields and buildings, more roads, plenty of people, shops and traffic, and the runway. It is 1995, and I have arrived, for the first time, in Lahad Datu.

I have made the same journey to Sabah’s east coast many times in the 20 years since. My most recent visit was last year in 2015. While the mountain has changed little, the view beyond is completely transformed. Little by little, that monotonous green canopy has become increasing dissected. Gaps formed where trees were felled, and a filamentous network of logging roads penetrated the forest. Later, fields appeared within the forest, but over the years these grew in size and number until they enclosed patches of remnant forest. A new crop, oil palm, became firmly established at the outskirts of Lahad Datu, then gradually spread westwards towards the mountain on the other side of Sabah.

Other changes were apparent. In 1995 Kota Kinabalu was little more than a three street town, albeit pleasantly vibrant. It is now a regionally important centre. Industries and small businesses have proliferated, and tourists throng the markets and restaurants. There are two universities and, to my great appreciation given my student days are long past, several excellent hotels. Kota Kinabalu’s development reflects the increasing wealth of the region, and it is the lowland dipterocarp rain forest that I see below my plane that has provided this wealth.

Dipterocarp is the critical term. On Borneo, the Dipterocarpaceae comprise around 270 species of mostly massive trees. There are a further 200 species across Asia, and a few more in Africa. It is in Borneo, however, where they are most impressive. Over half the tree canopies that I saw through the plane window were dipterocarps. Crucially for our story, dipterocarp trees have excellent timber, and have been sought out all over Southeast Asia by logging companies. The unprocessed timber from a single tree can be worth over a thousand dollars. Malaysia’s timber export market is around US$1.3 billion annually. In dipterocarp forests, money really does grow on trees.

We have, however, also lost something. Dipterocarp forests are among the most biologically rich habitats anywhere on Earth. Orang-utans loom large in tourist brochures, but they are but the most charismatic of a great many forest denizens. When the gloom of the deep forest is alleviated by a gap in the canopy, we see birds, butterflies, beetles, and bees come and go. Lizards cautiously peer round tree trunks, while ants obliviously follow regimented schedules. A silent exclamation declaims a green viper in the undergrowth, motionless and poised. Canopy cacophonies of morning birds and evening frogs reveal much that we do not see. The trees underpin this biological wealth. Dipterocarps surround us, some with immense buttresses, and trunks that soar high into the canopy. None is quite the same as the next, and close inspection reveals a plenitude of forms. There is, literally, value in this view of life, as tourists flocking to Malaysia’s natural parks contribute US$12.3 billion to its economy.

My flights across Sabah have witnessed the loss of much of this forest. We should not be despondent — much still remains. What remains is often degraded, but it will recover with time. Indeed, Sabah has recognised its imperative to safeguard its biological heritage for the global community, as well as for its own citizens.

Research with our Malaysian partners in Sabah has taught me much about dipterocarps, but I have also learned something about society. True, logging and oil palm plantations have devastated large swathes of tropical dipterocarp forest, but in Sabah at least it is also the case that policy makers, land managers, and scientists, are working together to restore degraded forests to their former states.