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Historical droughts in east and south-east Kalimantan
The Hulu Sungai district of south-east Kalimantan provides a particularly suitable region in which to trace the historical impact of drought. It has for centuries been a heavily populated rice-growing area, regularly reported upon by Dutch administrators since 1860 when they assumed direct government over the former Banjarmasin sultanate. Rainfall records are available with only occasional gaps for two stations, Amuntai and Barabai, from 1880 to 1941, and for seven additional stations for periods ranging from 15 to 40 years. A number of other stations have been added since independence, but there are many gaps in the data.
The El Niņo of 1877/78 and the La Niņa of 1879
Lying south of the equator and in the lee of the Meratus mountains, the Hulu Sungai and its environs normally experience a three-month dry season during the south-east monsoon between July and September. In El Niņo years the dry weather may continue for five or even six months, as it does in normal years in south-eastern Indonesia. Although rainfall statistics were not collected during the 1870s, the severity of the abnormal climatic conditions in 1877 and 1878 was remarked upon in the Annual Reports of the Residency (Algemeene Verslagen). Rice crops failed because of the long drought in 1877/78, and were then mediocre in 1879 as a result of La Nina flooding.
By that time, the situation of the population was stated to be "critical" (Meijer, 1880). Although data are not fully reliable, records show that total numbers of people in the area under direct Dutch control dropped from 444,175 in 1876 to 423,496 in 1879, with each year showing a progressive decline. There was no discussion as to whether some people might have died of starvation, though Dayaks and others in upland areas were said to be subsisting on wild yams. The authorities responded by providing paid work in drainage and canal construction, while at the same time importing rice. Some of the drop in numbers might, however, have come from out-migration, as people from the Hulu Sungai responded to the invitation of the Sul tan of Kutai (immediately to the north, in modern East Kalimantan) offering them land and remission of debts.
Kutai itself had also fared badly in the 1877/78 drought. Bock, the Danish explorer travellingin the area in 1879, described dead forests and hard-pressed Dayaks, who had to depend on food supplies sent into the villages by the Sultan. In Muara Kaman on the middle Mahakam, where one-third of the forest trees had died, the drought of 1878 was said to have lasted eight to nine months (Bock, 1881). Many of the Banjarese immigrants settled in the lake district of the middle Mahakam. The lakes themselves would certainly have dried up in the 1877/78 drought, which makes sense of the story, persistent in local oral history, that fish fingerlings had to be brought from the Hulu Sungai to stock them (Potter, 1993a). These lakes also became dry in 1914, 1982/83, and 1991 and, by implication, perhaps in other years of unusually severe drought in the past.
1885,1888, and 1891
Droughts reappeared in the Hulu Sungai (as elsewhere in Indonesia) in 1885, 1888, and 1891 (Allen, Brookfield, and Byron, 1989). In 1885 it was mentioned in the Annual Reports that there had been differential impact on the rice crops of the district. Those of Amuntai, which, owing to deep flooding during the rains, normally grew only in the dry season, had fared quite well, but rain-fed sawah and upland shifting-cultivation rice had failed completely. Rainfall figures indeed show Barabai, chief centre of the rain-fed rice area, as experiencing the greater drop in available moisture. The 1888 event produced a six-month dry season in Amuntai but heavy rain for the rest of the year; that of 1891 was more marked, with five dry months but a 30 per cent reduction in the annual total. In 1888, the failure of tobacco crops that were being experimentally produced around Amuntai was announced. With failed crops and no sources of cash income, Banjarese began looking beyond Borneo for means of subsistence. By 1899 the Resident noted that so many people were moving it was becoming difficult to collect taxes (Boers, 1899).
1902
In 1902, rice crops recorded their lowest yield for the 20-year period from 1895 to 1914, returning less than 45 per cent of the average (Lindblad, 1988, using statistics from the Koloninal Verslag). Although much of the Hulu Sungai experienced a six-month dry season in 1902, part of the problem with the rice crops appears to have been the excessively heavy rainfall that occurred during the growing season, before the dry weather became established. This is similar to what happened in northcentral Java (Commissie, 1903). Barabai, the centre of rain-fed sawah production, was deluged with 2,737 mm from January to April, more than its mean annual rainfall and enough to drown most crops. This was followed by only 460 mm over the following six months, just over half the amount expected in a normal year. This tendency for heavy rainfall to precede or succeed the onset of an El Niņo has been noted for other events, and Brookfield and Allen (1991) suggest that this is a much more serious cause of distress in subsistence agriculture in South-East Asia and the Pacific than is drought itself.
By the time of the 1902 drought, a number of commercial tobacco plantations had been established around the edges of the Hulu Sungai district, following the passing of the Agrarian Regulation for South and East Kalimantan in 1888, which allowed lands to be taken up under long lease. Although some of these enterprises were speculative, others provided a useful source of local income. During its brief heyday, 1,000 workers were employed at one estate. Competition from Sumatra was beginning to prove a problem by 1900, however, and the 1902 drought, which resulted in extensive failures in production, led to the closure of a number of enterprises. By 1905 the tobacco industry was all but dead.
Perhaps because swidden fires escaped more readily in a long dry season, the colonial authorities moved to institute bans on upland burning during 1902 in a vain attempt to control shifting cultivation and stop the spread of Imperata cylindrica grass, which is easily inflammable but fire tolerant. A later comment was that such a ban must fail, as there was already so much grassland (Wentholt, 1938).
1914
The 1914 event was found by Brookfield and Allen (1991) to have been the major regional dry event between 1877/78 and 1982/83. This conclusion was based on use of a dry-period index calculated by Allen (1989), and applied across the whole region by Allen, Brookfield, and Byron (1989). It is from 1914 that we have the first clear evidence of extensive forest burning in Borneo. Resident Rijckmans (1916) noted that the drought lasted until November and it was not until December that good rains arrived. As a result of the long and fierce drought, enormous damage was done to the forests, in which great complexes were destroyed by fire. Van der Laan (1925) looked back on the 1914 experience a few years later and was more specific, referring to burning of peat soil in the swamp forests "through which beautiful forest complexes die." Endert (1927: 233), travelling through "Middle-eastern Borneo" in 1925, noticed some hill forest that showed signs of having been burnt "after a fire in a very dry year, roughly ten years ago" - this could very well have been 1914. This particular patch was thin-stemmed, poor in species, and surrounded by much richer and taller forest. From Sabah comes evidence also that a large conflagration destroyed the forests in an area south of Mt Kinabalu, known as the "Sook Plain," which has subsequently remained as Imperata grassland (Cockburn, 1974). D. Matthews, the Conservator of Forests for British North Borneo, wrote in 1917 that a very wide area of forest "between Keningau and mile 41 on the Keningau-Sook Valley bridle path" had been destroyed by fire, probably "a very widespread and destructive one in the year 1914 to 1915." He continued: "The fire very apparently started as a ground fire but in places climbed the trunks of the trees to the crowns, a very rare occurrence in tropical forests" (Matthews, 1917). He estimated the destruction of the forest to have occurred over 100 square miles, girdling all the large trees and destroying the undergrowth as well. The drought in Sabah, at least on the west coast, took place between March and May 1914 and caused considerable declines in production on the rubber estates (Straits Times [Singapore], 21 November 1914; 27 November 1914).
There was also contemporary description of widespread smoke and haze. The harbour master at Samarinda was reported by Braak (1915) as writing that "the haziness, often becoming mists, was largely caused by bush fires which could be smelled and caused pain to one's eyes." The Straits Times of 31 October reported a large fire in "West Central Borneo" and added: "Huge columns of smoke have spread themselves for miles around, hanging low over the sea and inconveniencing the ship routes in the Muntok and Karimata straits." Such descriptions were corroborated by Braak, who stated that ships' captains travelling along the Borneo coast, in the west between Pontianak and Sinkawang, and in the east off Pasir, complained of poor visibility and at times had pieces of burning grass land on their decks. The whole coast of Borneo, as well as parts of Sumatra, Maluku, and other areas, appeared to be covered in mist or smoke (Break, 1915).
The length of this drought was exceptional in many districts, one of the most notable being Muara Muntai (middle Mahakam). The total rainfall reported for that station for 1914 was only 904 mm, with the drought lasting nine months, from February to December. During the drought period, only 34 per cent of mean rainfall was received, which makes this drought comparable with that of 1982/83, in which 32 per cent of the mean was received in Muara Muntai over 11 months. Again the Mahakam lakes would have been dry, as Van Gelder (1915) reported for Martapura (not nearly as strongly affected) that the pools and lakes had dried up and the young fish had died. The rivers were also extremely low, with transport becoming impossible in the upper reaches of large streams such as the Mahakam and Barito. Resident Rijckmans reported an epidemic of smallpox but noted that cholera, usually endemic in the district, had fortunately not risen to epidemic proportions. Comments were made about the difficulty of procuring safe drinking water in Banjarmasin.
In south-east Borneo, studies were undertaken of the possibilities for irrigation works in the rice districts. Although an irrigation bureau was set up in 1919, very little was done. Resident Grijzen (1917) had suggested that often it was flood control, as much as drought, that caused the major problems. He was critical, however, of one report on irrigation possibilities, which suggested that Banjarese were not really interested in intensive farming. It was not until the late 1930s that some irrigation dams were constructed along the mountainous rim of the Hulu Sungai and an attempt was made to empolder one difficult swamp section, Alabio island. Meantime, smallholder rubber was beginning to solve the problem of cash incomes in the district, so that failure of rice crops was no longer quite so catastrophic. Although droughts did affect rubber yields, the dry period of 1925 coincided with a rubber boom and scarcely elicited comment. One important change that also occurred was greatly to increase the planted rice area from the 1930s, by bringing under cultivation large sections of tidal swamps. Some Banjarese from Hulu Sungai moved permanently to those lands, while others would travel temporarily to reap their annual harvests. The tidal swamplands were more vulnerable to drought because their specially adapted rices had a long growing season, their harvest not taking place until August, well after the rainfed rice had been reaped (Potter, 1993a).
1940-1941
Between 1914 and the "modern" droughts of 1965, 1972, and 1982/ 83, it is only the dry period of the 1940s that is remembered. That was a very confused time, with the Japanese invasion taking place early in 1942. Informants remember that an exodus from the villages to the city of Banjarmasin (the earliest of a continuing series of rural-urban migrations) was initially triggered off by drought and resulting crop losses.
Modern droughts and fires
Selection among the data
Here we concentrate almost wholly on 1982/83 and 1991 -1994, because of both the volume of material available and their relative importance. Moreover, the political violence of 1965 may have eclipsed any drought impacts in southeast Borneo but the 1972 season was remembered for the drying up of rivers, initially a basis for comparison with 1982/83. The Straits Times of 14 October 1972 reported quite extensive forest fires over South Kalimantan from satellite pictures.
The 1982/83 El Niņo The event in South and East Kalimantan and Sabah
The 1982/83 event has received extensive coverage for its extreme length and severity, as well as its worldwide impacts (Kerr, 1983; Philander, 1983; Canby 1984; Kiladis and Diaz, 1986; Allen, 1989). Studies by Leighton (1984) and by Leighton and Wirawan (1986) for East Kalimantan and by Beaman et al. (1985) for Sabah present comparable analyses of rainfall data for selected stations during the drought period. Whereas Leighton's data are restricted to a small part of East Kalimantan, those for Sabah are representative of a wider area. Both indicate an extraordinarily long dry period, although they cover a slightly different time-scale - from June 1982 to May 1983 in the case of East Kalimantan (which is also applicable to areas further south) and from September 1982 to June 1983 for Sabah. The unique extension of the drought period so far beyond its normal seasonal limits, including the whole of the following wet season, distinguishes the 1982/83 event from all others, except perhaps that of 1877/78. The most severe dry period was in fact from February to April 1983, the middle of the normal wet season. Although Sabah's seasons are somewhat different, the same concentration of extreme dryness occurred in the early part of 1983. Rainfall was only 32 per cent of normal throughout the dry period for the East Kalimantan stations and 39 per cent for Sabah. Leighton (1984) reported that many normally evergreen canopy trees in the primary forest at Mentoko (Kutai National Park) began shedding their leaves during February and March 1983 in response to the drought, which was ac companied by excessive heat. Fires occurred in East Kalimantan in September to November 1982 and March to May 1983, and in Sabah largely from February to May 1983, but in northern Sabah fires continued to be reported until August 1983.
The 1982/83 El Niņo The newspaper record for South and East Kalimantan
Whereas the Kalimantan literature has concentrated on the resulting fire, other impacts have not been fully documented. The two-year record provided by the South Kalimantan Banjarmasin Post (BP), a leading regional Indonesianlanguage daily, allows the wider context to be assessed. It is interesting that the year 1982 began with very heavy rainfall and serious floods in the northern Hulu Sungai, with thousands of hectares of sawah ruined, roads washed away, and 563 houses destroyed (BP, 7 January 1982). In February, 23,000 ha of rice fields were storing insufficient water as bunds and irrigation channels had been damaged and structures for water diversion in streams had been washed away (BP, 13 February 1982). The rain-fed crop, harvested in April, was thus poor.
The beginning of June saw the start of the dry season, with salt water already intruding into the Barito-Martapura river system at Banjarmasin. People were warned not to drink the river water but to buy fresh water (BP, 6 July 1982). New transmigrants in tidal swamp areas received special water deliveries from the government, but other settlers were not so lucky. At Balikpapan, private trucks assisted government agencies and the national oil company in distributing water from underground supplies (BP, 24 August 1982). News from Central Kalimantan was of streams drying in their upper reaches, disrupting transportation but making life easier for gold panners, who were able to operate in new locations where waters were unusually shallow. Everywhere, salt-water intrusion forced people to seek drinking water from small but drying tributaries. Cholera and diarrhoea soon broke out, and some deaths occurred.
Forest fires began in Central Kalimantan by the end of August, with dense smoke preventing planes from landing at Palangkaraya (BP, 31 August 1982). A month later almost all Kalimantan airports were closed as fires spread. Thick smoke blanketed the Mahakam River and Samarinda city in East Kalimantan, and the sky was constantly red. One reporter described the scene along the Balikpapan-Samarinda highway, with huge trees half a metre in diameter blackened into charcoal or half collapsed into ash. He stated that farmers settled illegally in the protected forest at Bukit Soeharto, bordering the road, burnt undergrowth and weeds around their crops, only to see the crops destroyed and the surrounding large dry trees also ignite. Shifting cultivators were soon blamed, with reports that bans on burning had been ignored (BP, 17 and 19 September 1982).
River levels in South Kalimantan had become critical. The Negara dropped from 62,399 cubic metres per second (cumecs) in June to 8,481 in September, the Barabai from 21,128 to 1,128. The low level of the Riam Kanan reservoir, which supplied hydropower to the province, eventually made it almost non-operational and electricity supplies to the cities of Banjarmasin, Martapura, and Banjarbaru were substantially reduced (BP, 23 January 1983). In April and May 1983 there were attempts at cloud-seeding over the reservoir, but they were unsuccessful (BP, 12 and 24 April 1983; 8 May 1983). By March 1983, both Samarinda and Balikpapan were facing serious water problems with wells running dry; people found themselves having to pay large sums for their water needs (BP, 8 and 26 March 1983). At the end of March, Samarinda was once again covered in smoke, which entered the closed houses. Roads were closed because of poor visibility and boat traffic was disrupted on the upper Mahakam River.
The 10-month drought in East Kalimantan was declared by local officials to be a national disaster. It was understood that thousands of hectares of forest had burned along the Mahakam and between Samarinda and Balikpapan. Crops had been destroyed, cattle had died of thirst, while fishermen had lost their livelihood (BP, 30 March 1983). Not until normal rains returned late in May 1983 was the crisis over.
The scale of damage did not at once become widely known. However, in December 1983 it was reported in the Banjarmasin Post that 3.1 million ha of forest had been burnt. The major conclusions of an aerial study by a combined team from the German aid project "Transmigration Area Development" and the local university were reproduced. According to Asiaweek, this "leaking" of the report caused some furore in official government circles, because the Germans had been asked to keep their findings secret. A fuller report was apparently sent from Hamburg by another Antara journalist and efforts were made to keep it out of Kompas, the mass circulation Jakarta daily, where it was eventually run in March 1984 (Asiaweek, 1984).
The 1982/83 El Niņo Scientific studies in East Kalimantan and Sabah The earliest scientific study, carried out by both aerial and ground survey over five weeks (Lennertz and Panzer, 1983: 12), was aimed at evaluating the impact of the drought and fire on future land-use planning. It concluded that 3.5 million ha had been degraded by `'natural drought and man-made fires." Crowns of trees were classified into three groups: (1) drought damaged but not burned; (2) moderately burned; (3) severely burned. The severity of the disaster was stated to be the result of "an unfortunate combination of adverse climatic conditions, fire-based shifting cultivation and the accumulation of easily inflammable logging residue" (ibid.: 14). A high rate of dead trees in logged-over forests (62 per cent as against 50 per cent in unlogged areas) indicated that logging operations favoured the development of intensive fires. Up to 75 per cent of the area was considered to be severely damaged, especially in the swamp forests, where mortality reached 90 per cent.
While some government officials were still playing down the seriousness of the fire (Asiaweek, 1984), the Lennertz and Panzer report was challenged by the Indonesian ecologist, Wirawan, on the grounds that the classification of forest damage was too rough and the survey time too short. He suggested that large areas within the burned region were probably undamaged or suffering drought damage only. A detailed ground survey of park and reserve areas indicated that, in Kutai Nature Reserve for example, damage was confined to zones that had previously been logged, with more serious damage in the more intensively logged sections. One swamp-forest reserve, however, had become a treeless lake (Wirawan, 1984a, 1984b).
Leighton, who had conducted research on the northern edge of Kutai Reserve in 1977-1979, returned in September 1983 to assess the impact of the fire on the primary forest. A cool ground fire had slowly burned through the area in April. Wirawan sampled a similar forest 20 kilometres away that had been drought-stressed only. Collectively (Leighton, 1984; Wirawan, 1984b), they found that all the large lianas were killed on burned sites and that over 90 per cent of the small saplings in burned primary forest were killed; in unburned forest this was only 25 per cent. Moreover, large trees had lower mortality in burned forest, most of the mortality being due to drought. Tree mortality on wetter alluvial soils was half that on drier sites.
Similar studies were undertaken in Sabah by Woods (1989) in which pairs of burned and unburned plots were compared for prim ary forest and forest that had been logged two years and six years respectively before the fire. In the area logged two years previously, mortality due to drought and fire was 2.5 times greater than that due to drought alone, with trees previously damaged by logging suffering higher mortality. As in the Kalimantan study, the smaller trees were more often killed by the fire than were larger ones, but the overall mortality of large trees was still high in the much hotter fires that occurred in the secondary forest. Mortality in the unlogged forest was lower than in all similar size categories in the logged forest. Woods concluded that fire in combination with previous logging had the most serious impact on forest structure, with both greater sapling mortality and loss of canopy cover. Where canopy loss was high, an increase was noted in the density of invasive grasses and creepers, while post-fire sapling growth was mainly of secondary species, with few upper-canopy species and a reduction in total species diversity and density. This would greatly reduce the regeneration potential of the dipterocarps, which would have to depend on the survival of a few large "mother" trees whose density in the secondary forests was quite low. A final general conclusion was that disturbed forests were more fire-prone than primary forests. The Sabah fires reported by Beaman et al. (1985) burned over 1 million ha of forest land, of which 85 per cent had been logged.
Later studies and the impact on wildlife
The Kutai Nature Reserve had its status changed to that of a National Park in 1985. The impacts of the fire on animal and insect populations were examined for sections of the area by Leighton and Wirawan (1986) and by members of a Japanese-led team in 1988. Leighton noted the disproportionate death by fire of fruit trees, suppliers of food to primates and large birds, such as hornbills, and of lianas and figs, important for primates. He noted heavy losses of frugivorous birds and of seed-eating squirrels, but found the primates to be surprisingly resilient, probably because of their ability to subsist on bark and leaves where fruit stores disappeared. The Japanese studies, conducted a few years later, used sightings and transect censuses in attempts to estimate animal populations. Conclusions indicated a drop in leaf monkeys, and few macaques were seen (Azuma, 1988), but orangutans were scarcely affected (Suzuki, 1988). Other studies showed that macaques, like the orangutans, had successfully adapted their diets to environmental changes and were feeding on secondary species (Boer, 1989). Mayer's work on the vil rages (1989) showed that, although pigs and deer had been killed by the fire, their populations recovered quickly and they continued to be pests of cultivation. Sightings of freshwater dolphins, which formerly inhabited the Mahakam lakes, had decreased because of the drying of the lakes, the death of fish, and the subsequent pollution of the Mahakam River with fire debris (Boer, 1989). Wirawan (1993) has added that the dolphins, as well as the local fish, suffered from serious skin infections.
An ambitious follow-up study of the total burned area was undertaken by Schindele, Thoma, and Panzer (1989), the results of a project entitled "Investigation of the Steps Needed to Rehabilitate the Areas of East Kalimantan Seriously Affected by Fire." Seven years after the fire it was not possible to distinguish drought from fire damage. A total of 2.81 million ha of lowland dipterocarp forest was found to be damaged by drought and fire, of which 1.1 million was lightly disturbed, 0.98 million moderately disturbed, and 0.73 million heavily disturbed. In addition, 0.49 million ha of swamp forest was burned, with 90,000 ha completely destroyed.
One major conclusion was that "it was not the drought which caused this huge fire, but the changed condition of the forest" (Schindele, Thoma, and Panzer, 1989: 71). The most heavily disturbed area coincided with both the districts of most recent logging intensity and those of the highest population densities. The authors were not optimistic about the regeneration possibilities of the most heavily disturbed sites, where in many cases the entire forest structure had been destroyed and replaced by pioneers. Lightly disturbed forests, on the other hand, still retained their structure, with fire affecting only the low and middle storeys. Species diversity continued to be high and dipterocarp seed trees remained in the vicinity. These forests were considered largely able to recover by themselves (ibid: 104). In between were the moderately disturbed forests in which there was the greatest need for enrichment planting of dipterocarps and other rehabilitation measures if their recovery for timber production was to be possible within 100 years (ibid: 111). Rehabilitation would be more complicated because differences in soils and topography led to variability in damage sustained over short distances.
People and forest management
A commissioned study of local populations by Mayer found, perhaps predictably, that villagers questioned in East Kalimantan about their attitudes to forest management were very concerned about forests in their immediate area but had no interest in those further afield. They reported that the lack of non-timber forest products, such as rattan, damar (for resin), and gaharu (aloe wood), was having a severe impact on their incomes, perhaps the most severe long-term impact of the drought and fire once the immediate short-term problems of failed/burned crops and water shortages were overcome. Others bemoaned lost jobs on the concessions as many firms scaled down their operations (Mayer, 1989).
It was suggested that a long-term pilot project in dipterocarp regeneration be set up on 30,000-50,000 ha, in which local and transmigrant populations could be integrated into forestry activities and strategies for fire prevention would be developed and implemented (Schindele and Thoma, 1989). Unfortunately the proposal for a model regeneration site was rejected by the funding agencies, apparently because of its long time-frame. Since 1983 there has been little attempt at enrichment planting or other techniques to improve regeneration of dipterocarps. The concentration has been on fastgrowing plantations of Acacia mangium, Paraserianthes falcataria, and Eucalyptus deglupta, destined eventually for pulp. Such plantations are also very easily combustible. A minor drought in 1987 and the more noteworthy event in 19911994, discussed below, were accompanied by further fires and considerable areas of plantations perished.
There has also been little attempt to involve either local people or transmigrants in forest management, although the new plantations often bring with them a contingent of transmigrant labourers (see chap. 10).
The El Niņo of 1991-1995
A briefer discussion only is offered of the most recent fire event, the product of a prolonged and not yet fully understood El Niņo period that began in 1991 and did not end until early 1995. Our data refer only to the 1991/92 period. Potter spent time in Banjarmasin and the Hulu Sungai (South Kalimantan) and in Balikpapan, Samarinda, and the middle Mahakam (East Kalimantan) during October 1991, when the drought and accompanying fires were at their height. Newspaper coverage of this drought was obtained for the months of AugustOctober 1991.
Incomplete rainfall data for 1991/92 reveal, for one East Kalimantan station, a situation very similar to that in 1982/83. Apart from a brief interlude in November 1991, drought continued from June 1991 through April 1992. Total rainfall for the 11 months was only 484 mm, of which 60 per cent fell during November 1991. At Kota Kinabalu, in Sabah, a period of very low rainfall similarly lasted from August 1991 to May 1992. From field observation and reading of the newspaper record, this event was severe, at least in terms of its disruption of people's lives. There was considerable burning of both swamp forest and plantation in South Kalimantan, at the previously damaged Bukit Soeharto reserve in East Kalimantan, and in the vicinity of Muara Teweh and Palangkaraya in Central Kalimantan. Around Palangkaraya the fires covered 76,000 ha and isolated the town. Planes could not land and boat traffic was also restricted through poor visibility. Again, the burning of swamp forest seems to have been the cause, ascribed to the "carelessness" of the people (Dinamika Berita, 23 September 1991).
Apart from the fires, the other strong impression made on Potter was the amount of sickness that accompanied the drought. Lack of drinking water brought with it widespread epidemics of cholera and dysentery. Early October saw 2,000 sick in Samarinda and there were a number of deaths in Banjarmasin, particularly of poor people living in overcrowded barracks or similar housing.3 Central Kalimantan suffered at least 148 people dead for the year from "diare" or "muntaber," euphemisms for cholera (Dinamika Berita, 10 October 1991). Most were in isolated villages far from medical care.
Other problems mentioned were shutdowns of sawmills and wood factories in the cities because of the difficulty of obtaining raw material. Logs could not be floated down the streams because their upper reaches were too shallow. Airlines lost money because passengers could not fly, and one small plane disappeared in the fog and smoke. As usual, crops were destroyed, especially those from the tidal swamps. People simply walked off their lands to try and earn money somewhere else (Dinamika Berita, 21 August 1991; 18 and 19 September 1991;10 and 14 October 1991). The fishing industry was at a standstill. Potter visited the "lakes" of the middle Mahakam to find them dry and negotiable by motor bike.
It now seems evident that drought and fire have always been a part of the natural environment in Borneo, at least for the last several thousand years. The effect of this finding for the ecology of the tropical rain forest as a whole, especially in this wettest of regions, remains to be written. We cannot offer more. However, the impact of drought and fire over the past 10 years has been much more devastating than at any time in at least the previous 100 years, and probably much longer.
Human adjustment is yet another matter. The unfortunate experiences that the population has endured as a result of these "visitations" of fire and drought have not produced systems to cope with recurring disasters. The record shows that the forest and even the primates have developed patterns of adaptation, so that El Niņos trigger fruiting mechanisms in dipterocarps and primates can adjust diets to overcome scarcity of preferred foods. Moreover, the indigenous Dayaks and other long-settled farming populations suffer, but find means of adaptation. In the Tinjar valley of Sarawak, for example, rice production of one village, calculated from data in Lian (1987: 139), fell to only 54 per cent of the 1978-1985 mean in 1982, but this was compensated by additional planting, leading to a peak production of 130 per cent of the mean in 1983. On the other hand, the modern population of Borneo, depending as it largely does on the use of forest resources, is not able to handle the impact of severe drought. With more people and more logging, and hence an inherently unstable and combustible forest, plus inadequate water supply, health care, and transport systems, a situation of serious endangerment, made worse with every new drought, has already been reached.
Notes
1. Most of the Peninsula falls into categories C1 and C2 (5-6
wet months) or D1 and D2 (3-4 wet months), with short to moderate
dry seasons. Exceptions are the Highlands (A) and western Johor
(B1). Jelebu, in Negri Sembilan, with a four-month dry season, is
classified E3, which has no Bornean counterpart. Its annual mean
is slightly higher than the chest Borneo stations (data from
Chan, 1984; Dale, 1959/60).
2. The one lower-rainfall area for which there is a poor
correlation of drought with El Niņo is that in the north-west of
the Peninsula, which has a climatic regime different from that of
the rest of the region.
3. At Pontianak in West Kalimantan, falling river levels in the
Kapuas permitted salt water to enter the city water-supply
intakes, leading to an immediate shutdown in the whole system,
and supply only by trucks for a period of some months.
One of the major elements of criticality, as addressed in this book, concerns the degradation of land cover. The conversion of oldgrowth forest to various secondary formations as a result of agriculture and logging activities has already been discussed. The opening of gaps in the canopy allows light to penetrate the forest floor and may create a suitable environment for the establishment of lightloving invasive grassy weeds, of which Imperata cylindrica is the most infamous. This grass, which has many different names in different countries, is known as alang-alang in Indonesia and as lalang in Malaysia. For convenience and easier use of the literature, these national names are used interchangeably with lmperata wherever appropriate in this chapter. Under certain conditions this grass may become dominant over wide areas, a position that it maintains through its tolerance of fire. There are parts of the region where this conversion to "sheet alang-alang" has occurred, particularly in south-east Kalimantan. From colonial times through to the present, officials have viewed such a transformation with alarm, and there is no doubt that the grassland ecosystem has much less to offer than the forest in terms of biodiversity, total biomass for the maintenance of soil fertility and carbon capture, and as a producer of useful materials for human populations. That it does provide some opportunities is less well known and less frequently mentioned in the literature. These opportunities will be discussed in this chapter.
Local people and their shifting-cultivation systems have usually been viewed as the main "culprits" in the forest-grassland trans formation, and indeed they have often created grassland, usually on a small scale and with full understanding of the results of their behaviour. The current rate of attack on the forests, through logging, land settlement, and other pressures, would appear to be creating the conditions for a rapid and irreversible increase in grassland formation. This has led to predictions of doom by some observers and statements such as: "Currently, land use throughout Kalimantan is on an unstable trajectory of net conversion of rainforest to alang-alang, without yet the development of sustainable systems of productive agriculture, of productive managed forestry and of protection of nature reserves" (Leighton and Peart, 1988). The fact that one of these authors, a biologist, has been carryi_ng out research in parks and nature reserves in Kalimantan over more than 10 years gives weight to such a pronouncement. If indeed this were the case, one might well claim an imminent state of "criticality" for Kalimantan and, by extension, the rest of Borneo. We do not believe that this scenario accurately represents the future, but it is clear that the question of the grasslands needs detailed examination, to which we now turn our attention.