Conditions in Mae Chaem are indicative of many problems and challenges facing upper tributary watersheds in northern Thailand. Recent changes in land use include the growth of commercial agriculture associated with opium crop substitution and decreased rotational shifting cultivation. Changing land use has led to increased tensions, as downstream populations blame practices in the mountains for floods, droughts, sedimentation, and a perceived decline in water quality. To help address these issues, the World Agroforestry Centre (ICRAF) is working with local sub-watershed management networks to develop ways to increase communication, trust, transparency, and accountability among communities and government units.
One focus of this work is on the use of simple, locally managed science-based methods for monitoring watershed services. Upper tributary landscapes are composed of fairly complex mosaic patterns of various cultivated and non-cultivated land use practices. The net impacts of these various configurations on watershed services are subject to considerable speculation and much debate, the vast majority of which is based far more on theory, emotional impressions, and/or vested interests than on empirical evidence. Thus, the project has sought to test a set of simple science-based tools employed by members of local villages in the context of their sub-watershed management network, in order to produce information useful for:
Feedback on the impacts of local land use management on watershed services;
Helping manage watershed service-related tensions and conflicts among local communities; and
Facilitating communication and negotiations between local upland communities and downstream communities and the broader society regarding the impacts of land use in upper tributary watersheds.
Study sites
The 12 sites in this project were located in 4 sub-watersheds (Mae Raek, Mae Kong Kha, Mae Suk, Mae Yot) of the nearly 4000 km2 Mae Chaem watershed in northern Thailand's Chiang Mai Province. Mae Chaem is a major sub-basin of the Ping River Basin, which is the largest tributary of the Chao Phraya River system that feeds the famous irrigated agricultural production systems of Thailand's central plains region, as well as Bangkok.
Testing the monitoring toolkit
Four basic sets of tools were selected for this initial exploration in community-based monitoring.
Climate and stream flow
The first set of tools focused on daily measurements of basic climatic variables, including rainfall, maximum and minimum temperatures, and relative humidity, along with weekly indicators of stream flow. Rainfall, temperature, and relative humidity were measured with simple devices. Simple structures or shelters were made for these instruments at a location within or near the village settlement area where daily readings could be made and recorded with minimal inconvenience.
Stream flow was monitored by measuring stream depth and surface flow velocity. Water depth was a simple weekly measurement at the same point using an improvised staff gauge. Surface velocity was estimated using a leaf or foam float and a stop watch to time its travel time along a 5–10-m measured distance, averaged over a series of at least 5 runs. Water temperature was also measured.
Data collected by villagers appear comparable to data collected by more sophisticated techniques. Data patterns are comparable to official sources at similar elevation, and differences among elevations are similar for both sources.
Stream water quality
Overall water quality monitoring used a bio-indicator approach based on work conducted by researchers seeking to adapt similar approaches used in the United Kingdom. Background materials and methods are detailed in handbooks and guides that are packaged along with an identification key and associated materials in a Stream Detectives Package, originally published in Thai, and now available in English from the Green World Foundation based in Bangkok.
Scores assigned to organisms collected at a particular site and time are aggregated to provide an overall index of water quality based on weighted scores of the resulting ‘suite’ of species. The index has a 10-point scale that can place water quality into one of the 5 categories. This method requires only simple equipment, and identification of specific organisms is facilitated by local knowledge and familiarity with many of them. An identification key helps match the system with local names and provides a score for different groups of organisms, based on their relative sensitivity or tolerance to factors contributing to poor water quality. Earlier trials showed aquatic invertebrates compared favorably with other types of bio-indicators, including algae, diatoms, and aquatic plants, but the former are easier for villagers to learn and implement. Although many villagers were initially apprehensive about the difficulty of this method, it has become one of the most popular and highly regarded of our monitoring tools (Figure 1).
Soil erosion and stream sediment
The third category of data focused on simple measurements of stream sediment, and on soil movement in cultivated fields. Stream sediment data were collected weekly and reflected the project's effort to contribute to compilation of data to verify linkages between stream water turbidity and its actual sediment content. Soil movement in cultivated fields was measured monthly, using a simple soil ‘bridge.’ This method allows the detection of both soil loss and soil accumulation, and replicate pairs of such sites were established at upper, middle, and lower slope locations of selected cultivated fields.
Local environmental knowledge
The fourth category of monitoring data focused on identifying local environmental knowledge related to the watershed measurements. Most initial information was on local indicators of weather conditions, particularly indicators of rainfall or drought events. Fewer data were collected on factors affecting soil characteristics related to soil erosion. Village data collection volunteers made efforts to record the time, place, and prediction associated with a given indicator and the person making the observation. Data records from rainfall and temperature monitoring activities could then be used to systematically verify the accuracy of the prediction. Villagers at several locations are finding this a very interesting activity for helping to analyze the range of local indicators.
Assessing performance quality in the use of monitoring indicators
To assess monitoring efforts, scientific and field staff collaborated in developing basic criteria for evaluating the completeness and consistency of data records generated by village monitor volunteers at each of the 12 main monitoring sites over a 30-month period. While none of the sites were able to achieve a complete high quality data record, results of these initial pilot efforts conducted by village volunteers were quite impressive at many sites. Village volunteers were able to explain reasons for a number of the gaps and inconsistencies in their data records by describing some of the problems they encountered during the data collection process.
Lessons for further use of watershed monitoring tools
Participating villagers were also asked to give their opinions about the different measurements, based on their perceptions of how useful the data would be for them in the context of their local issues and watershed management network. All villagers agreed on the relevance and utility of collecting temperature, humidity, rainfall, and water quality data, as well as relevant information on local knowledge. Opinions were split on the usefulness of data on stream depth and water temperature.
In addition to opinions about the various types of simple science-based tools, volunteers gave these additional suggestions about collecting data on watershed services:
Authority for data collectors needs to be derived from relationships with a network or a local sub-district government unit.
All relevant ethnic groups in the local area should be included.
It is important to have periodic meetings among data collectors in various sub-watersheds, in order to exchange data and information.
Persons providing extension support services must give sufficient time to training in collecting, interpreting, and using data, building understanding and answering questions, and helping point out its importance.
Data collectors should have sufficient basic knowledge or ability to learn quickly.
An appropriate modest amount of compensation is necessary.
Activities should be coordinated with village headmen to help them appreciate the usefulness and importance of the data.
The need for data by researchers, watershed managers, or technicians must be matched with the needs of local people from the outset in order to prevent conflicts, as the data needs of watershed managers probably differ from the needs of villagers.
Use of science-based tools, together with local environmental knowledge in participatory watershed monitoring and management, is possible, and communities have seen that knowledge from these 2 sources can be combined to increase their usefulness. But 2 issues need careful consideration:
Confusion about use and interpretation of data from science-based tools; and
Study of factors that can help support emergence of these activities, considering that volunteers must manage their time carefully.
There will likely be a need for adaptation to local contexts that may affect what data are collected, as well as the completeness of data records. Local monitors also want to exchange knowledge and experience. Thus, future efforts need to emphasize easy tool use and data interpretation, and ways to support information exchange, in order to facilitate the widespread use and acceptability of data among villagers, technicians, other stakeholders, and policy decision-makers at various levels.
Additional biological indicators of environmental quality
Given the importance of and interest in use of biological indicators, among villagers and our colleagues at governmental and non-governmental institutions, additional work in this area was led by Dr Pornchai Preechapanya of the Northern Watershed Research Center. He and his staff printed and distributed a Handbook for Inspecting Environmental Quality that catalogs 133 entries of biological indicators of water, soil, forest, air, and general environmental quality. Entries cover a range of indicator organisms, including aquatic invertebrates, fish, algae, plants, mammals, amphibians, reptiles, birds, and insects. Information includes local and scientific names, pictures, and details about what they can indicate in terms of environmental quality characteristics.
FURTHER READING
Notes
[1] Pornwilai Saipothong, Pornchai Preechapanya, Thanat Promduang, Nongluck Kaewpoka, David E. Thomas
World Agroforestry Centre (ICRAF), PO Box 267 CMU Post Office, Chiang Mai 50202, Thailand. P.Saipothong@cgiar.org (P.S.); pcpc@loxinfo.co.th (P.P.); D.Thomas@cgiar.org (D.T.)