|Conservation and Development in Northern Thailand. Proceedings of a Programmatic Workshop on Agro-forestry and Highland-Lowland Interactive Systems, Held at Chiang Mai, Thailand, 13-17 November 1978 (UNU, 1980, 114 pages)|
Recent studies have discussed relationships between narrowly defined ecosystems and human activities or human biology.' These have led to interesting developments in the concept of human adaptation to extreme environments. and to a better understanding of the human ecology of small isolated groups, but the results have had limited applicability. Most human groups capitalize on resources from several different zones rather than confining their activities to a single zone, and humans characteristically make major modifications of the microenvironments in which they live. Moreover. the association between human activities and particular ecological zones has become progressively weaker Modern technology has led to increased ability to make extensive or localized environmental modifications, and these modifications have increased with the growing densities of human populations Population movements between ecological zones have become more frequent, and local economic systems have been increasingly affected. modified, or dominated by regional, national, and world wide economic systems. For these reasons it is appropriate for us to consider human activities and resource use within the region of Northern Thailand in terms of interaction between the two major ecological zones or types-the highland and the lowland. Emphasizing the interactions between zones is a break with the tradition of planning for development within a single zone which assumes correspondence with the boundaries of a self-contained system. This has proved to be an unrealistic and ineffective approach, particularly in the highlands.
This paper deals with some of the human aspects of highland-lowland interactions in Northern Thailand, including the distribution of ethnic groups and local economic systems. distribution and demographic characteristics of the population, socio economic conditions of the people, and implications of changes in these variables for development. We are thus interested in the combination of agriculture and foresty in the region as a whole, as well as in local economic systems in which agriculture and forestry are combined.
Forests remain mostly in the relatively sparsely populated highlands; they have been cleared from most of the intensively cultivated, densely populated lowlands. Nonetheless, we proceed from the belief that economic-environmental problems of Northern Thailand, including questions of the interaction of forestry and agriculture. are regional, not confined to one altitude (highland vs. lowland), nor restricted to one ethnic group. or one type of local economic system (highland swiddeners vs. lowland ethnic Thai irrigated rice farmers). For reasons which will become evident, we believe human and natural resources will be better conserved in the course of development if highlands and lowlands are viewed as interacting parts of a regional system. The nature of highland-lowland interaction is changing rapidly in association with demographic, socio economic, and cultural changes. to the detriment of environmental conditions in the region. This implies the usefulness of the regional view in planning and evaluating development projects designed to solve problems both on the natural resource side (deforestation, erosion. flooding) and on the human side (population growth and movement, poverty, opium production, and inequalities in the distribution of social benefits such as education. health, material possessions, and ability to control and improve one's life situation).
The major concerns of lowlanders with the highlands have been suppression of opium cultivation and protection and exploitation of forest and watershed resources for the benefit of the lowlanders. The basic concern of most of the highlanders is in getting enough to eat. Development projects in the highlands have emphasized the technology of production, and have demonstrated the possibility of growing a variety of crops (including native and exotic forest species) of benefit primarily to lowland economic interests. Little attention has been paid to the improvement of highlander subsistence production. The development projects have failed to raise the standard of living of all but a minuscule fraction of the highlanders, and have slowed neither the pace of environmental degradation nor the rate of highland population growth. In several instances they have in fact contributed to increased pressure on the land because of their failure to attend to problems of subsistence of villagers displaced from their customary swidden areas. In order to solve development problems, it is necessary to tackle such problems as land tenure and marketing as well as reforestation and crop substitution. Because extreme poverty is an outstanding characteristic of highlanders. any humanitarian solution must first ensure adequate subsistence for the highlanders, as well as protection of lowland interests.
Commercialization has proceeded rapidly in Northern Thailand since the end of the Second World War. At that time there was some differentiation of land-use types based on environmental zones. but most people were primarily subsistence rice farmers and made small use of the market. In the past three decades an increasing number of types of land use or local economic systems can be distinguished in various Northern Thailand environments. At the same time, the nature of the interactions between highland and lowland has been changing rapidly. mostly in the direction of increasing gaps between the poor and the rich, and increasing economic and other domination of highlanders by lowlanders. Traditionally the level of living standard of highlanders and lowlanders was rather similar, with highlanders enjoying some economic advantages and lowlanders enjoying others. The urban centres in the lowlands and the national and international markets in which they participate have increased demands for highland resources. As lowland administrative control has expanded. and as transportation and other technologies have improved and have become more capital intensive. Iowlanders are better able to control directly the production of these resources. We believe that the physical and social separation of the production of these resources. from the point of their consumption, has important implications for the conservation of natural and human resources,
Ethnic Groups and Local Economic Systems in Northern Thailand
It has been conventional to assume a close correspondence between ethnic groups, local economic systems, and ecological or altitudinal zones in Northern Thailand (e.g. Credner 1935; Uhlig 1969; Van Roy 1971, chaps. 2 and 3). This has led to a typology in which the distribution of ecological zones, ethnic groups, and local economies is neatly arranged in the form of a layer cake. According to this typology, which, as we shall see, is no longer adequate, the soggy bottom layer is populated by wet-rice growing ethnic Northern Thais, living in the lowland valleys: the drier middle layers are occupied by Karen and Lua' rice swiddeners. and the frosting on the top of the dewcovered peaks is provided by opium-growing groups such as Hmong. Yao, Akha. Lisu, and Lahu. In fact, today there are so many exceptions to these stereotypes that they are misleading for development planning. In some highland areas ethnic Northern Thais outnumber the other groups; in other highland zones the upland minority people depend at least as much on irrigated rice as on swidden rice; a major portion of the highland minority groups are actually wetrice growers in the lowlands; highlanders are flocking in increasing numbers to join the lowland labour force; and the boundaries between supposedly distinct ethnic groups are notoriously permeable and subject to redefinition. For these reasons it is appropriate to move beyond geographic typologies to consider the implications of socioeconomic and demographic processes as they relate to regional development.
Urban nodes, neglected in the layer-cake stereotype. are becoming increasingly important in the major valleys, both as centres of population and as loci of services. They also are taking on growing importance as centres of change in agricultural technology and in the commercialization of land ownership and land use, and as centres for the diffusion of other aspects of modern urbanism to rural areas. Between the 1960 and 1970 censuses (Thailand 1962: 1972), while population in the Northern Region grew at a rate of 2.56 per cent per year. population in municipal (urban) areas increased 3.43 per cent per year, from 287,189 to 439,854. This represented an increase from about 5 to about 6 per cent of the total population of the North. These figures, which on a world scale or in comparison with Central Thailand represent a low rate and low amount of urbanization, understate the penetration of urbanism into rural areas. Smaller urban clusters, such as district towns, have probably been growing more rapidly in size than have municipal areas, and clearly they have been acquiring urban services at a rapid rate. At the same time. the social characteristics associated with modern urban life are changing, at least in the lowlands There have been important increases. for example. in proportions of people attending school, in the highest grade of schooling completed, and in types of employment (both job type and type of industry), with a general decline in agricultural employment and increase in non-agricultural jobs. Still, the rural areas. especially the highlands, lag far behind the urban areas in these indexes of modernization. Education is a prerequisite for upward mobility in the non-agricultural occupations. Because their access to education is so much more limited, residents of rural areas. especially highlanders, are cut off from this path to upward social mobility.
The civil service. banks. and other employers of national scope have established a national pattern in which the educated urbanized employees are transferred between urban centres. Although quantitative data are not available. it seems clear that urban centres of the North are increasingly the place of origin of migrants destined for other urban places in Thailand, and also the destination of highly trained migrants from other urban places in Thailand Thus in terms of their elite populations. as well as in their economic orientation, urban centres are becoming delocalized, and oriented more to Bangkok than to the region in which they are located. At the same time these urban centres are the destination of increasing numbers of unskilled, underemployed and landless northerners, both from the lowlands and from the hills. This pattern of increasing differentiation in the urban places of the North between the better educated, nationally oriented elite and the local unskilled underemployed workers suggests that it is probably fortunate that these urban centres are not growing in size any faster than they are. It should be noted that this pattern of social differentiation is not restricted to the large urban centres such as Chiang Mai, but is also to be found in the smaller provincial towns and even in district towns in the North (Kunstadler 1971; 1978h) Some of the elite residents of the urban centres are approaching. reaching, or surpassing average Western levels in education, professional competence. income. material standard. and life expectancy at birth (Knodel and Chamratrithirong 1978). The urban poor, most rural dwellers, and even the highlanders are aware of these changes, but have received only a small share of the benefits of modernization. Their life chances remain limited. as measured in educational, economic, or demographic terms. Among these groups the highlanders, in general. are those with the most limited opportunities.
Highland-lowland interaction is seen in the large towns in terms of sales of highlander products (e 9, crafts. fermented tea) and raw materials (e.g.. Iumber) for which the highlands are important sources. As lowland markets and trading networks broaden. and as consumer tastes change. the highlands are sometimes supplemented or replaced as the sources of goods or services that they formerly supplied to the region. Highlanders are no longer employed as caravaneers, having been replaced by trucks over the rapidly improving road network (Kunstadter 1967): ''hill-tribe style" clothing, sewn in Chiang Mai or Bangkok, is sold on national and world markets at lower prices than the authentic pieces would bring; highland-grown early-ripening rice, which once found a market in isolated lowland towns prior to the lowland harvest, is being replaced by lower cost rice trucked in from other areas (Kunstadter 1978b. p 119); and fermented tea (miang) is being replaced with more modern-seeming stimulants ( Keen 1978b, pp 267- 268, Table 14.5). Lowland demand for highland resources, such as lumber. tin, and other minerals is increasing, but highlanders benefit only marginally and temporarily. The land taken for mining or forestry projects is removed from use for subsistence agriculture. and most of these resources are extracted in unprocessed form-with a very low proportion of the sale price going to the highlanders-rather than being processed or taken on a sustained yield basis The net effect to the highlanders is loss of land for agriculture without adequate substitution of income (Kunstadler and Chapman 1978. p. 21; Kunstadter 1978b. pp. 293 298; Marlowe 1969) Lowland ruralurban interaction is seen not only in the flow of food and other commodities from rural producers to urban markets, but also, increasingly. in the flow of rural people to urban jobs to seek urban health, educational, and other services ( Renard 1977).
Land-use patterns or local economic systems in the rural low valley lands have been differentiated by the development of large-scale irrigation works in the North. To the longestablished rain-fed paddies and small scale irrigation systems, which allowed wet rice farming only in the monsoon rainy season, have been added larger-scale dams and ditch networks, some of which provide year-round water and allow multiple cropping in favourably located fields Even prior to the development of irrigation systems allowing multiple cropping. cash cropping in the valley lands was increasing rapidly, with ever larger areas being devoted to annual crops of garlic, soybeans. peanuts. and tobacco. grown on rice fields in the dry season. Also, with the development of rapid transportation and wider markets, some irrigated fields were being converted to tree crops.
In these rural lowland valleys, interaction between highland and lowland has been largely in the form of some seasonal employment of highlanders whose rice harvests are completed several months earlier than those in the valley. The effects of the increasing intensity of agricultural land use on the lowlands on highland-lowland interaction has not yet been studied (David Pfanner, personal communication, 1978). Because of the increasing substantial growth of landless or "underlanded'' agricultural populations in the lowlands (see. e.g., Chapman 1978b), as well as the increasing mechanization of farming, there will not be an increased demand for highlanders in the lowland labour market. On the contrary. increasing migration of lowlanders to the hills can be expected.
It should be noted that both ethnic Thais and minority groups living in the rural lowland valleys have participated in the intensification of lowland agriculture. though the proportions involved are not known. The two largest minority groups with both highland and lowland representatives are Karen and Lua' Most Lua' who lived in long-established lowland villages have become assimilated to such an extent that they have become Northern Thais in terms of their self-ascribed identity. their patterns of land use. and other aspects of their culture. as seen. for example. in old, assimilated Lua' villages in Amphoe San Patong (i.e., San Patong District) southwest of Chiang Mai, or in the Yuam valley, south of Mae Sariang (Kunstadter 1966). Some Karen villages in the Ping valley. whose inhabitants are descendants of resettled captives from wars with Burma, are also thoroughly assimliated, but most Karens living in the lowlands maintain their distinctive ethnic identity, for example in Amphoe
Hot of Chiang Mail Amphoe Li of Lamphun, Amphoe Mae Sariang and King Amphoe Mae La Noi of Mae Hong Son Province. They are predominantly lowland wet-rice farmers (as are many Karen in Burma). They maintain kinship and other connections with highland villagers of the same group. Recent Karen and Lua' migrants from the highlands to the lowlands usually enter lowland society at the bottom stratum. Unless they have money or relatives who can give them a start. they try to establish themselves as unskilled day labourers, seasonal farmworkers, etc., or may engage in periodic or daily commuting to the forest to gather leaves, mushrooms. or other forest products for sale in the market. Those who are a little better established may have regular jobs working as servants or doing unskilled jobs, or may have accumulated enough capital to go to the hills to purchase vegetables for sale in the lowland markets. In the past some have been able to acquire irrigated land of their own, but it seems unlikely that many of the recent migrants will be able to do so because of the scarcity of unclaimed potentially irrigable land, the rapid increase in land prices relative to the price of unskilled labour. and because the large supply of unskilled labour in the lowlands is likely to keep the wages low.
Between the irrigated or rain-fed rice fields in the lowland valleys and the highland areas occupied by people who are originally or primarily swiddeners. Lies a foothill zone which is generally not continuously used or occupied. Occasionally such marginal areas. which often have lower rainfall and sandier soils than in the hills, may be cultivated by highland villagers. In recent years they have become the destination of landless or underlanded lowlanders. They go seasonally to the unirrigable gentle upper slopes ("upper terraces" in geological terms) of the lowland valleys, or into the steeper slopes of the foothills for short cultivation-short or long fallow supplemental swiddening of subsistence or cash crops. In some areas such as those described by Chapman (1967; 1978a). this pattern is well established and includes customary community claims to the swiddened area.
Land at higher elevations with greater rainfall and with soils having better water retention was once the exclusive domain of older established minority groups (Karen, Htin, Lua'), living in permanent villages. They practice short cultivation-long fallow swiddening for subsistence crops, supplemented with increasing areas of small-scale irrigated fields where terrain and water supplies permit. In some areas wet rice now supplies as much, or more. subsistence crop as does swiddening. Many of these people supplement their subsistence agriculture by seasonal wage work in other locations (harvesting in lowland fields, mining, lumbering, clearing and weeding opium fields, temporary unskilled labour in towns, etc.) (Kunstadler 1969; Marlowe 1969). Traditionally they have deliberately maintained the forest vegetation on ridgetops. along water courses. and in sacred groves for protection against erosion, as sources of seed for forest regrowth and as sources of useful species found only in deep forests. They have also actively fought forest fires to protect the swidden regrowth. and have used numerous techniques to reduce soil erosion. to which they expect to return for another round of cultivation in about 10 years (Kunstadler 1978b; 1978e).
Groups which have arrived in Thailand more recently (Hmong, Yao. etc.) farm these same elevations, if they can obtain the land between or within areas customarily cultivated by the autochthonous highland people. They may also farm at slightly higher elevations, which may be less desirable for subsistence crops because of slope, soil qualities, or forest cover. They often practice long cultivation-long fallow swiddening with a mixture of subsistence (rice, maize) and cash crops (opium, maize, pigs, etc.). They may select their cultivation sites because of special soil qualities (basic soils in limestone areas), because of the availability of seasonal labour supplies and subsistence commodities from nearby Karen and Lua'villages. or because of remoteness from lowland officials who might interfere with opium production. They do not control fires as effectively as Lua' and Karen villagers, they practice clear cutting and clean deep weeding regardless of problems of soil erosion and reforestation, with the result that where they cultivate the forest vegetation is replaced with a persistent grassland when the area is abandoned after a long period of cultivation (Keen 1978a).
Some members of groups such as the Hmong, who in Thailand have in general moved their highland villages from place to place as the soil became exhausted, are now being forced by land shortages to seek alternative solutions. In some cases they have begun to cultivate grasslands (Keen 1978a, pp 258 - 259), and in increasing numbers they are coming to the lowlands either to seek work, sell their handicrafts, or to seek land for permanent field farming. Given their reputation as inveterate highlanders who are willing to search for hundreds of miles for suitable swidden sites, and who will work only for themselves, this suggests the extent of land shortage in the highlands.
At the higher elevations, depending on the natural occurrence of the wild tea plant (Camellia sinensis). tea gardens, sometimes supplemented by small-scale irrigated or swiddened rice fields, are occupied by Northern Thai, Khmu'. Labu. and other groups. In addition to the land occupied and used for crops, or from which tea is harvested, their local economic system makes extensive use of wood from still higher elevations, as fuel for tea processing. For many of the people with lowland origins, working in the tea gardens is often seen as a means of accumulating cash with which to buy irrigated fields in the lowlands (Van Roy 1971: Keen 1978b). Thus their movement to the highlands is part of a migration cycle related to land shortages and land prices in the lowlands.
In the past, tree planting has not been vigorously pursued to replace the lumber which was extracted. Most tree planting was done at the lower elevations in areas not particularly well suited for swiddening, and most of the plantations were of teak. Small but increasing areas in the highlands are now devoted to tree plantations sponsored by the Forest Industries Organization. These are occupied mostly by landless lowlanders, and to a lesser extent by highlanders. Residents in the forest villages are given access to land for swiddening in return for labour in clearing and planting, and for cultivating lumber trees. In some of these projects villagers have supplemented their earnings by wage work elsewhere, or by raising and selling cash crops. Because of the relatively long cycle on which teak is grown (60 years minimum) this form of land use cannot support as many people per unit area as traditional subsistence swiddening on a short cultivation-long fallow cycle (Kunstadter 1978d, pp. 296-298), but at least in the more successful projects the standard of living may be higher than in subsistence swiddening villages. Other plantation schemes, such as the pine plantation at Baw Luang (ibid ). and the recently begun mulberry planting scheme on the foothills west of San Patong. offer much less income to highlanders than they would obtain from swiddening, and at the same time remove land from cultivation on a ten-year cycle for a forest crop harvested at much less frequent intervals.
The conflict between forestry and subsistence farming has become increasingly acute in the past few years. Land at the middle altitudes is being alienated from its long-established customary use in regular rotation swidden systems. Large areas are being reforested on contract by concessionaires irrespective of their productive use in regular rotation subsistence swiddening. This has already led to armed confrontations between the lowland concessionaires seeking to complete their contracts and highland villagers who receive no benefit from the land which will henceforth be protected forest.
This process, aside from its social and political implications, can be expected to increase the pressure on the land remaining for agriculture. decreasing the time available for swidden fallow, with consequent declines in subsistence production. and it will increase deleterious environmental effects (erosion, replacement of forest by grass cover in the fallow period). Swidden agriculture, although it provides subsistence to the vast majority of highlanders, is not recognized as a legitimate type of agro -forestry.
There is a small but increasing amount of cash cropping in the hills, sponsored by lowland officials or entrepreneurs, employing highland workers. Examples include the King's Projects, and the various heavily subsidized schemes for crop substitution among opium growers. In the private sector this can be seen. for example, in the fields planted with cabbages, strung for several kilometres along the road from Hot to Mae Sariang, managed by lowland entrepreneurs, using highland Karen workers. Although several of these appear to be technologically successful. it is yet to be demonstrated that they offer socially or economically feasible alternatives to subsistence swiddening for the majority of the highland population (McKinnon 1978) It is also apparent that they often bring with them serious unresolved socio-economic and environmental problems associated, for example, with road building, permanent removal of forest covers. and changing patterns of land ownership and management.
Lowland personnel and economic interests dominate highland-lowland interactions regardless of local economic type or the ethnic groups involved. Thailand as a whole is modernizing rapidly, at least materially, but the highland-lowland relationships in many ways resemble the socio-economic conditions of an earlier period in many developing countries. Highland resources are drained off to benefit a small number of modernized urbanites far removed physically and socially from the highlands. Highland economies continue to stress agriculture and extractive industries while the emphasis in the lowlands, especially in urban centres, shifts to manufacturing, commerce. and service industries. Socio-economic gaps, measured by income. education, and material standard of living, and reflected in malnutrition and mortality rates, grow wider between the highlanders and modern urbanites. Traditional authority of highland village officials is weakened as the power of the central government expands. Traditional landholdings of the highlanders are taken by decree or force, and the indigenous highland population cannot protect its resources. Modern urbanites assume cultural superiority over the highlanders, who lack opportunities for upward social mobility even through education. Also, as we shall see, conditions are apparently being created which favour rapid population growth while natural increase in the urban centres has sharply declined.
The Demographic Situation in the Hills and Valleys of Northern Thailand
The total population of the 16 provinces of the Northern Region of Thailand was 7,488,683 in 1970, having grown at an annual rate of 2.56 per cent since the 1960 census (Thailand 1962; 1973). Most of the people live in relatively narrow, intensively cultivated valleys. Tribal Research Centre surveys in 1973 77 indicated there were 316.793 minority group highlanders in these provinces (Kunstadter 1978g, Table 1). Allowing for some unsurveyed highlander communities, this suggests that minority group highlanders represented about 4 per cent of the regional total, not including the tens of thousands of highlander refugees who have arrived in Thailand from Laos and Burma since 1975. The number of ethnic Northern Thais engaged in swiddening or other occupations at elevations above the lowland valleys, while known to be high, has not been systematically counted or estimated. This number may reach or surpass the number of minority group highlanders (Chapman 1967: 1978; Judd 1964).
Nationally there are very strong rural-urban and socioeconomic differentials in vital rates (e.g.. Chamratrithirong and Boonpratuang 1978; Knodel and Chamratrithirong 1978: Kunstadter 1978h). Within the Northern Region recent demographic research has suggested a dramatic decline in birth and natural increase rates. Crude birth rates fell from about 43.7 to 26.6 per 1,000 between 1964-65 and 1974 75, and this decline-which was apparent in reproductive histories-has now been confirmed by use of other types of data. including vital registration and school registration (Thailand 1969; 1977a; Pardthaisong 1978, p. 29). The birth rate did not fall evenly in the region. There were strong ruralurban, educational and occupational differentials. Urban residence, nonagricultural jobs and higher education are associated with lower fertility (Chamratrithirong and Boonpratuang 1978, p. 6). Although fertility has been declining in the rural North it remained high in the more remote districts with sizeable highland populations, at least in Chiang Mai Province, which otherwise has been a leader in the decline of fertility in the North (Pardthaisong 1978. pp. 20ff). Evidence from age distributions of highland minority peoples also supports the conclusion that highlanders have maintained high, and in some cases extremely high, fertility levels (Kunstadter 1978b. Table 4).
Strong rural-urban differences in mortality rates exist in the North, with rural children having more than twice the probability of dying than do urban children (Chamratrithirong and Boonpratuang 1978. Table B). Mortality rates have been falling throughout the region, from 12.4 per 1,000 in 1964 65 to 10.5 per 1,000 in 1974-75 (Thailand 1969,1977a). In the lowlands the mortality decline has apparently been more than matched by fertility decline, thereby reducing the rate of natural increase. In the highlands, where mortality rates have probably not fallen so far or so fast, the higher level of fertility is apparently sufficient to maintain higher growth rates than in the valley. The rates of natural increase among some highland groups (e.g., Hmong, Yao, and Lahu) are greater than 3 per cent per year (Kunstadler 1978g). The high birth, death, and growth rates are associated with relatively high dependency ratios'° among the highlanders, probably exceeding the already high Thailand national level of 100 1 in many groups (Arnold and Boonpratuang 1977, p. 7, Kunstadter 1978g. Table 3) This suggests either that the burden of economic support is even heavier on adults in the highlands than in the lowlands, or more probably, that the young children must contribute more heavily to the family income in the highlands. In either case, the situation implies problems of development in the need for education for very large numbers of highland children (see below).
Census figures for the North in 1960 and 1970 show an increase from 10.9 per cent to 13.2 per cent of people born in a province other than that of present residence, while the proportion of inter-province migrants aged five and above who moved within the five years prior to the census increased from 3.3 per cent to 7.0 per cent (Thailand 1962. 1972: 1973). About half of the interprovincial movements were within the Northern Region, most of the remainder originating from the Northeast and Central regions (see Ng 1969 for an analysis of interregional moves from the 1960 census) A total of 214,933 (3.4 per cent of the regional total population aged 5 and above) moved into the North from other regions of Thailand in the five years prior to the 1970 census At least an additional 3.771 moved into the region from other countries.'] This number has been greatly increased in the past five years by refugees, particularly minority people such as Karen from Burma, moving into Mae Hong Son and probably Tak provinces, and Hmong and Yao from Laos moving mainly into Chiang Rai and Nan provinces.
Although there is a clear trend towards migration both within the North and between regions in Thailand, internal migration has apparently declined as a source for population growth in the North Net migration into the North declined from about 32,000 in the five years prior to the 1960 census (equivalent to about 0.56 per cent of the regional population) to about 10,000 in the five years prior to the 1970 census (about 0.14 per cent of the total regional population) (derived from Thailand 1962, Table 6; 1973, Table 8).
Interzonal population movement between highlands and lowlands in the region has not been well documented or quantified. Nonetheless, the pace of movement has probably increased. probably in both directions. and clearly involving both temporary and permanent movements. This is suggested in the lowlands by the visible increase in the number and variety of highlanders visiting the markets, selling goods, and seeking employment, and by the growing number and size of settlements of deliberately or spontaneously relocated highlanders. In the highlands. improvement of transportation is accompanied by the appearance of increasing numbers of lowlanders, especially in settlements associated with government and quasi-government projects adjacent to newly built roads.
Motives for such movements varied, though probably predominantly economic. Most of the highlanders moving out of the hills do so because of their chronic inability to make a living. Some move because of personal disaster (prolonged illness, fire) from which they lack the resources to recover; others may be expelled from the villages for violations of local taboos or inability to get along with their neighbours. This type of movement to the lowlands is probably becoming increasingly common because former patterns of migration within the highlands are no longer possible or attractive: the splitting of villages and movement to unoccupied land is no longer easy because of land scarcity in the hills. movement of individuals or families from one ethnic group to villages of another group, e.g., between Lua' and Karen, may not be as welcome as land becomes more scarce; movement from Lua' or Karen to Hmong or other opium producing villages which need additional labour may not be desirable because of fear of involvement with opium trade or addiction etc. Lowlanders apparently move to the highlands to look for jobs (mostly government projects) which have either educational or citizenship requirements, or personal contacts not enjoyed by highlanders, or to seek land, especially in places where access has been improved by roads. The lowlanders' knowledge of land laws, as well as their contacts with officials, makes it much easier for them to establish a legal claim to these lands than it is for the highlanders who may have customaryuse rights to the same land. Thus, apparently, interethnic competition for land and jobs is increasing in both the lowlands and the highlands.
Lowland-highland differences and interactions may be seen with regard to fertility and mortality, as well as migration. The decline in fertility in Northern Thailand may be viewed as a process of diffusion starting from urban centres (including the very small clusters of urbanized people in district towns), perhaps as early as the late 1950s. By the late 1960s there were already clear and strong differentials in vital rates between urbanized people and those living in the rural and highland areas (see. e.g., Kunstadter 1971). Fertility has declined in association with the spread of modern urban characteristics (education, occupation, etc.) as well as with the increased availability and acceptability of modern, effective biomedical devices for birth limitation (see, e.g., Pardthaisong 1978). The spread of the conditions, motivations, and attitudes associated with planning for a small family. as well as the spread of birth control devices, has been slowest in the more remote rural areas, especially in the highlands. The limited data available regarding fertility among different highland groups seem consistent with the idea that the control of fertility is related to the local economic type. Cash cropping highlanders expanding into relatively sparsely settled areas, who may be able to use increased family labour supply (including the labour of young children) to increase cash income have high fertility; Northern Thais in the hills. who work in tea gardens in order to accumulate enough cash within a few years of hard work to buy irrigated fields in the lowlands have low fertility; subsistence swiddeners, whose productive system depends on the availability of family labour, but who are unable to accumulate and store wealth or use additional labour to increase income have an intermediate level of fertility. The correctness of the hypotheses of causal connections between fertility and local economy implied in these apparent associations needs to be verified with better quantitative research. This is important for development planning because of the possibility that conversion of subsistence farmers to cash cropping may imply both an increase in fertility and an increase in demand for land (Kunstadter 1978a; 1978g; Scholz 1969; Walker 1976, p. 176).
Adequate epidemiological data are not available to describe causes of death with great precision. but there are strong morbidity and mortality differentials associated with life in the highlands and in the lowlands, with considerably higher infant and child mortality among highlanders (Kunstadter 1971; 1978g, Table 8). It seems likely that dietary differences between the different local economies in the different ecological zones are associated with different types and degrees of malnutrition. Because of interaction of malnutrition and disease immunity (Awdeh et al. 1972) differences in local economies should in turn be associated with differences in infectious disease morbidity and mortality. The mortality differentials between lowlanders and highlanders are one sign of this. and the obvious stunting of growth and small body stature among many highlander populations is another. Dietary differences and changes associated with various local economic types is a subject for urgent research, particularly as dietary deterioration can be predicted in the course of transformation from the more varied diets based on subsistence farming and gathering economies (Kunstadter 1978d) to the less varied diets associated with low levels of cash income and in the absence of access to gardens and the gathering of wild forest products. The epidemic of dental caries. starting in urban areas within the past generation. is one sign of this; but the problem of extreme seasonal shortages in the diets of highlanders also requires study
The generally acknowledged failure of the malaria eradication programme, especially in the more remote and mountainous areas. and the current state of malaria epidemiology in Northern Thailand, especially near international borders, implies that increased movements of people into and through forested zones, both in the highlands and the lowlands will be associated with increased malaria incidence (cf WHO 1974). Resurgence of malaria apparently has already become a serious health problem among some highland populations. and this problem will probably be more serious in the more remote highland villages because of the difficulties in administering malaria control programmes there. On the other hand, because of their ecological isolation, remote rural areas, and especially highland populations, may have enjoyed some protection from widespread vector-borne and communicable diseases (Kunstadter 1972). Although protection from some of these diseases (smallpox, measles) can now be gained from vaccines or control programmes in the lowlands, the picture is not so optimistic for those diseases such as Japanese encephalitis, dengue and dengue haemorrhagic fever which have become increasingly prevalent in the lowlands in the past decade. It can be expected that the ecological separation which once protected highlanders from these diseases will be lost. The highlanders will be exposed increasingly to lowland diseases. as interzonal population movement increases. and as the modified environmental conditions of the lowlands are replicated in the hills.
These examples suggest the importance of further study and deliberate consideration of the unintended health consequences of ''development'' in the form of increased ease of movement between ecological zones, increased environmental modification in either highland or lowland, and increased transformation of subsistence into cash economies.
Population in the North continues to grow. The rate of growth is declining because of the rapid fall in fertility accompanied by only a slow fall in mortality. Population in the highlands is probably increasing at a more rapid rate than in the lowlands as a result of much higher fertility, in spite of higher mortality. Net migration to the hills may be at a greater rate than net migration in the lowlands. Interzonal migration is increasing the inter-ethnic competition for land and jobs in both zones Transformation from subsistence to cash economies in the highlands may have the unanticipated and undesired effect of increasing fertility, and development in both zones may be associated with undesired changes in morbidity and mortality conditions.