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close this bookConservation 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)
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View the documentProgramme on the use and management of natural resources
View the documentHighland-lowland interactive systems in the humid tropics and subtropics: The need for a conceptual basis for an applied research programme
View the documentNorthern Thailand: The problem

Highland-lowland interactive systems in the humid tropics and subtropics: The need for a conceptual basis for an applied research programme

Jack D. Ives


A study of highland-lowland interactive systems as a basis for improved resource management is one of several major systems studies that together constitute the United Nations University's Programme on the Use and Management of Natural Resources (NRP) An intellectual basis for such a topic can be traced back to the work of Carl Troll and to the more recent increase in awareness of the urgency to understand destructive environmental processes that result from continuation of traditional land-use practices in a situation of virtual uncontrolled human population growth. Thus, it was perhaps inevitable that Vice Rector Walther Manshard and Professor Gerardo Budowski would propose the inclusion of this project within the UNU programme It was perhaps also inevitable that they should recommend the harnessing of the existing resources of the International Geographical Union Commission on Mountain Geo-ecology and of the conceptual advances achieved under the Unesco Man and the Biosphere (MAB) Programme, Project 6: Study of the impact of human activities on mountain and tundra ecosystems.

By a process of small group discussions, pragmatic considerations, and field inspections. the Project on Highland Lowland Interactive Systems. in terms of actual field-work, now has three main components. Two of these are centred on the highlands of northwestern Thailand and Papua New Guinea respectively, and another is concerned with natural hazards mapping in the central or eastern Himalayas While the present workshop is concerned overwhelmingly with the refinement and development of research plans for the first component. I think it essential that we all devote some thought to the construction of a conceptual framework for the Project as a whole The need for this, I think, is two-fold. First, a conceptual framework would serve as a means of building a series of hypotheses to define more precisely the problems we wish to tackle and to identify the practical. manpower. and intellectual linkages between the three components of the project. both for its own sake and especially as a means of developing a uniqueness for the United Nations University such that we do not fall into the trap of merely undertaking a few small service projects indistinguishable from those of other United Nations and bilateral and unilateral agencies Thus, if we are to justify retention of our title-Highland-Lowland Interactive Systems-we must define what it means within the context of a series of precisely stated primary and secondary objectives that will not only contribute to geo-ecological science but will also achieve practical goals. These will presumably involve the improvement of the quality of life for at least a small sector of humankind, not at the expense of natural environment deterioration. but nopefully as a complement to increased environmental stability. If we achieve this, we will have fulfilled our commitment to the United Nations University, but a larger goal would be to develop our conceptual and practical approaches to the degree that they can be used as a general model, applicable to wide areas of the humid tropical and subtropical highland-lowland systems.

My paper. therefore, will consist of two parts. The first part will be a preliminary discussion of general concepts and definitions that seem to befit the project title The second part will be an attempt to apply these generalizations to the opportunities at hand in northwestern Thailand with Chiang Mai University as the academic and administrative springboard in its role as an Associated Institution of the United Nations University. But I must stress that this attempt is very preliminary indeed. I hope that the final outcome, based upon our combined efforts over these next few days, will very greatly modify and refine this rather modest beginning.

A Conceptual Framework

Concern over human impacts upon mountain environments has grown rapidly over the last five years, particularly as a result of the Unesco Man and the Biosphere (MAB) Programme, Project 6: Study of the impact of human activities on mountain and tundra environments. and the somewhat parallel work of the International Geographical Union Commission on Mountain Geo-ecology. The United Nations University's Project on Highland-Lowland Interactive Systems is serving both to broaden these considerations to embrace the lowlands, subjacent to the impacted highlands, which themselves are so frequently on the receiving end of progressive downslope impact under the influence of gravity, and to provide a sharper focus in the sense that we have adopted the humid tropics and subtropics for special attention. But consideration of the primary physical effects that environmental degradation in highlands perpetuates all the way downstream, even to the sea, is only a oneway view. Highlands and their neighbouring lowlands are frequently inextricably tied together by a series of both upslope- and downslope-trending processes that are physical, sociological, psychological, economic, and political in nature. Thus, as a first simplification it is perhaps advisable to attempt to describe the various sets of processes separately and to identify their principal direction of flow.

Physical processes

These can be described in simplest terms by considering a highland area devoid of human occupants. The interrelationships amongst climate, vegetation, soils. bedrock geology. and slope angle, under the influence of gravity, will produce a series of landscape adjustments controlled by base level and tectonic activity. This is best described as a series of processes by which the landscape seeks to attain a degree of geomorphic equilibrium in relation to a given time scale. These processes and their resultant landform assemblages can be modelled quite simply as a system of energy dissipation under gravity using the watershed concept to provide physical limits, or even two dimensionally (Figs. 1 - 3). All human impacts can be related to such a model through their primary and secondary modifications of it, and the complex feedback effects that can be hypothesized. Consequently, the watershed may prove the most convenient unit for the subsequent design of our research project, although it is by no means the only possible approach

FIG. 1. Model for the Study of Slope Processes. (From N. Caine, 1971, "A Conceptual Model for Alpine Slope Process Study," Arctic and Alpine Research, 3 (4): 319-329, Fig. 1.)

Before leaving our consideration of the physical processes, however, I would like to express a strong personal conviction. Any attempt to develop a long-term applied research project, with the objective of influencing human land-management practices, must have a conceptual framework that will facilitate an assessment of the possible range and magnitude of the impacts of any such changes in land-management practices on the environment that we begin with. While it is probably not possible to reconstruct the original natural landscape of the northern Thai highlands for use as a bench mark, we must attempt to understand as much as possible the extant physical processes and their changes through time. Without taking this into consideration we will never even approach the prospect of being able to predict what environmental impacts our research applications may have (prediction of their impacts upon human behavioural responses is an even greater task). Nevertheless, I believe we have here the justification for inclusion of a study of climatic and environmental changes through the last several thousand years, using methods such as those contained within the subdisciplines of palynology. sedimentology, dendrochronology. and paleoclimatology. I can perhaps best illustrate this with an example, or rather a parable that I used, unsuccessfully. I must admit. in an attempt to persuade the United States Department of the Interior to finance some palynological investigations in southwestern Colorado. My institute had been asked to be involved in a major research task to determine the possible ecological consequences of winter cloud-seeding in the San Juan Mountains. Winter cloud-seeding in the Rocky Mountains. if successful, should increase winter snow accumulation by a significant amount. Thus we were being asked to study the ecological impacts of artificially increased snowfall. not a particular problem in Thailand, but nevertheless an appropriate example.

I proposed to the review panel that we could describe climatic change in the form of God's impact upon world or regional climate. And since God frequently appears well ordered, His impact could be construed as a curve of set wavelength and amplitude which is usually regarded as climatic change. Be the curve regular or irregular. something simple can be drawn for the sake of illustration. The crucial questions then are, thinking in terms of the United States Secretary of the Interior and winter cloud-seeding. will the Secretary be in phase or out of phase with God, and will his impacts be of greater or lesser amplitude and wavelength than God's? Without an answer to these related questions we cannot determine the ecological impact of winter cloudseeding, and because the review panel remained unmoved to my golden-tongued and possibly blasphemous approach to raising money for palynological research, eight years and many millions of dollars later we still do not understand the ecological implications of cloud-seeding. Hopefully I have a more sympathetic audience on this occasion!

Human processes-highland

FIG. 2. The Hillslope Waste Budget. This model is intended for only small parts of the slope (on a scale of under 10 m). R is the waste discharged downslope; A is the waste acquired from upslope; W is the waste acquired from the weathering of bedrock in situ. (From N. Caine, 1974, "The Geomorphic Processes of the Alpine Environment,'' in J.D. Ives and R.G. Barry, Arctic and Alpine Environments. [London: Methuen], pp. 721-748, Fig. 12B2.)

Under this category we must include the original, relatively well-balanced, subsistence agricultural. hunting. and collecting systems that have prevailed in the highlands for centuries In the Northern Thai highlands this has presumably been a variety of forms of swidden agriculture with the production of opium frequently occurring as a cash crop. Next we must consider the impacts of rapid population growth on this subsistence system and its primary impacts on the highlands themselves, and their downstream effects. This presumably involves increased soil erosion and lowering of soil fertility through the ever shortening period of fallow and forest regrowth after fire. and a progressive change in the highland flora and fauna which in turn further accelerates loss of soil fertility and erosion to produce a vicious and accelerating circle. This quickly leads to the lowering of human nutritional levels and perhaps out-migration of the younger and more vigorous sectors of village society, with its own set of deleterious feedback effects. The results again tend to move downhill and have complex effects on the neighbouring lowlands.

Human processes-lowland

Traditionally. the world over. mountain or highland societies have been relatively small. fragmentary, and isolated. Thus people in the neighbouring lowlands with their greater ease of communication, larger societal units. richer land, and hence more powerful political institutions, generally have been able to exert political and economic control, to a greater or lesser degree, over the highland groups. In relatively primitive areas this may take the form of extraction of tribute, taxation, or military service; in more complex societies it can take the form of extension of land ownership through application of lowland capital and even development of a massive tourist industry with a high-cost infrastructure such as is characteristic of much of the Alps today.

Development of lowland "control" of highland areas, through application of political and/or economic power, will in turn have its own set of environmental and societal impacts and their attendant feedback mechanisms. These also must be taken into careful account as we reach the stage of changing the application of such political and economic power with the objective of altering land-use practices. This is of vital concern if our aspirations are the improvement in the quality of life of the hill peoples and their lowland neighbours. Evidently these processes, including those of the very research effort itself, proceed predominately from the lowlands to the highlands, although feedback effects will flow in both directions.

An outline for research

The foregoing has been admittedly rather simplistic. I hope you will excuse this, although it is perhaps adequate enough to serve as the basis for development of a research design as ambitious and as complex as we care to make it. Fig. 4 may help explain what I think could form the main elements of such a design.

Fig. 3 can obviously be exploded into a research design that would be completely beyond our technical, intellectual, and financial capacities. A vital component is also missing, namely recognition that a considerable body of knowledge and experience is already available. Thus we must make provision for the accumulation of the available relevant knowledge presumably in the archives of the project headquarters here at Chiang Mai University. We can also quite easily incorporate into any research design the ongoing research efforts. I believe we are all here today largely because of the strength and relevance of the Huai Thung Choa highland field project directed by our friend Dr. Pisit Voraurai. Similarly. the experience gained through the Thai-Australian Highland Agricultural Project and several others will provide a running start.

FIG. 3. The Stream Channel Sediment Budget. R is the sediment discharged down the channel; Ab is the sediment acquired from the slopes surrounding the channel; Ac is the sediment acquired from upchannel; W is the sediment acquired from erosion and weathering of the channel bed and banks in situ; S is the volume of sediment stored within the channel segment. (From Caine 1974, Fig. 12B3.)

From this point I think I had better restrict myself to a series of simple, pragmatic proposals and then await your criticism and comments Nevertheless, we must be aware of the catastrophic status and rapidly changing economic conditions in Northern Thailand. These will make decisions based upon extant conditions invalid. One of the great challenges facing us, therefore. will be our ability to anticipate the direction and magnitude of these changes

Specific Needs

1. To strengthen and build upon the existing structure of the Huai Thung Choa highland field project This would involve many specific additions and modifications to be recommended by Dr. Gerardo Budowski and the Agro Forestry Systems Project. Coupled with this is the recognition that significant contributions can be derived from links with the Tropical Agricultural Research and Training Centre, Costa Rica, including transfer of agro-forestry species and training.

2. Mapping of present vegetation patterns, using traditional field methods and air photograph interpretation and remote sensing. Full exploration of this suggestion must await the presentations of Dr. N. Wongtangswat and Dr. Michel Bruneau.

3. Mapping of land-ownership and land-use patterns and cultural features (allied to item 2).

4. Mapping of soils and landforms.

5 Establishment of a modest network of climatological stations representative of the field areas, range of altitude. aspect. and cover types. Amongst many other things. this should assist horticultural and agro-forestry applications by providing a framework for determination of ecological limits of introduced species.

6. Selection and instrumentation of a number of slopes with different altitudes aspects. and cover types, for determination of rates of soil erosion.

7. Establishment of hydrolopical stations on a few principal streams for study of hydrological variations and stream load

8 Extraction of lake sediment samples for pollen and macrofossil analysis to lay the foundation for a modest palaeo climatological investigation to provide a rough environmental trench mark. This latter project will he quite challenging because it will be necessary to build up a microscope reference slide collection for pollen identification.

FIG. 4. A Simplistic Model for Research Design for Highland-Lowland Interactive Systems

9 Extensive anthropological research so that a much fuller understanding of the relationships between the different ethnic groups and their environment can be developed. This understanding would then need to be extended to a study of the anthropologic and environmental impacts of any prospective land-use policy changes

10. Identification of ways and means of training graduate students and senior undergraduates to fit effectively into an interdisciplinary team project.


It would seem that there is a superb prospect of combining the existing Huai Thung Choa highland field project objectives with both the UNU Project on Agro-forestry Systems and the Project on Highland-Lowland Interactive Systems. My remarks. of course, are biased towards the latter. However, regardless of how we ultimately proceed, the research applications, as they take effect. should have significant environmental and human impacts themselves. It is imperative that adequate attempts be made to predict these possible impacts and to monitor the field area so that the predictions can be successively more precisely defined. It will probably be necessary to hold a small meeting to formulate the monitoring and prediction design after identification of the research objectives.