Understanding, classifying and mapping human use and natural resources in pilot wetlands of Cambodia and Vietnam to promote sustainable development (Collaborative study of small wetlands)

This research project seeks to define how people, fish, birds and wetlands are connected in the Mekong River Basin. Fish and birds utilize wetlands and are crucial to the overall richness of biological diversity in the Mekong Region. People also benefit greatly from wetland resources, but these uses cannot be incorporated into sustainable use plans unless they are understood and mapped. In the process of defining this relationship between wetlands and biological diversity, the proposal also endeavors to map the natural wetlands of the study areas and devise a classification system for these wetlands. Both the map and classification systems can help scientists, managers and decision-makers to better communicate the values inherent in these critical wetland ecosystems in the region.

Research questions

1.     Where are the wetlands of Kulen Promtep Wildlife Sanctuary and Yok Don National Park located and how can we map them?

2.     What ecosystem products and services do small wetlands in Kulen Promtep Wildlife Sanctuary and Yok Don National Park provide, including ecological functions?

3.     How do variations in wetland size, geomorphology, and hydrology influence bird and fish diversity?

4.     How do different kinds of development affect (in terms of both products and services) the various wetland types?

5.     How can small, scattered wetlands in Cambodia and Vietnam (in the tens of thousands) be classified?


Although there are likely more than 12,000 natural, small wetlands in Cambodia alone, these important ecosystems have not been examined in much detail anywhere in the Mekong Basin. Importantly, this estimate of natural wetlands does not include reservoirs or other human-made wetlands. Future phases of this work will expand from the foundation developed in the pilot areas to wetlands throughout the Mekong Basin. River development and changes in land-use are likely to alter these systems tremendously in the future. Without a basis for defining what, and how, wetlands and their associated biological diversity might be affected, it is impossible to understand the full impact of any proposed or planned development project.

The specific objective for this research project is to conduct wetland assessments by sampling natural ecosystems in two pilot areas, one in Cambodia and one in Vietnam, that serve as bird and fish habitat, as well as providing other valuable ecosystem services. These direct-sampling and social surveys will provide bird, fish, and wetlands data to develop a wetland inventory that is spatially explicit and thus expandable.


Wetlands are relatively small with size ranges from 0.3 hectare to 100 hectares and they are scattered throughout the study areas in both countries. In Kulen Promtep Wildlife Sanctuary, the average wetlands size is typically larger than 1 hectare; in Yok Don national park, however, most wetlands are smaller than 0.5 hectares. Collectively, wetlands in both conservation areas span a useful range in size, water permanence and geomorphology so that our classification system will likely cover a large variety of wetland types. Smaller wetlands are difficult to detect with Landsat 7 imagery. To locate small wetlands on maps that we create, we will use different resources that are available and free aerial imageries on Google Earth. Ground truth data will be very important to create a model for mapping the other wetlands that are not surveyed.

The research project will conduct surveys of wetlands, and associated bird and fish diversity, by sampling ecosystems in and near two conservation areas of Cambodia and Vietnam that may serve as fish breeding or nursery habitats – Kulen Promtep Wildlife Sanctuary and Yok Don National Park. Data on water permanence and quality, soil characteristics, flora and fauna (i.e., plants, birds and fish), as well as socio-economic conditions from nearby villages or from reserve guards (e.g., information on livelihood activities, integrating a gender perspective), will be collected. Human surveys will provide data not only on wetland resource use but also on long-term hydrological trends and fish use.

Policy impacts expected

For policy makers to make science-based decisions that influence regional wetland ecosystems, they need credible scientific information from trusted expert sources. Data can be used to engage people with identifying and empowering alternative ways that these small wetlands can be developed more sustainably. The first step in this process is to identify that these wetlands exist and to map where these wetlands are so that we can create model sites to develop alternative development scenarios that protect biological diversity. Though this step may seem simple it is a crucial first step that has not been taken after 20 years of these wetlands being documented to some extent.

Specific policies (related to boundary partners):

•    National-level decision-making: Cambodia (Ministry of the Environment and Ministry of Agriculture) – The wetland maps, if adopted, will be used as tools to influence development plans and other resource management decisions. Lands in wildlife sanctuaries are still being lost to development in Cambodia as governmental agencies allow development to continue encroaching on conservation areas. We will use the research findings to engage the ministry with identifying and empowering alternative ways that these small wetlands can be developed more sustainably. Results of this study will be presented in several formats to the Ministry of the Environment and the Ministry of Agriculture, thus this policy impact would occur mostly after the project completion.

•   Local-level decision-making: Yok Don National Park (Vietnam) has often destroyed small wetlands by digging them out so that water remains in them all year. Other management actions at both parks have worked at cross-purposes as well. These management actions reflect an incomplete understanding of the role that small, natural wetlands play. Digging wetlands out does provide permanent water, an important asset to wildlife in the open forest. But digging out the wetlands also has the unintended consequence of destroying nesting habitat for most wetland bird species and reduces overall biological diversity. By providing important data on the biological diversity of all different habitats (inundated seasonally as well as year-round), the research project can influence the parks’ decision to engage in this practice. This impact could happen during the course of the project, and we can provide the park management with preliminary information for their use.

Lead contact

Dr. Duong Van Ni, CEO Wetland University Network

Can Tho University, Environmental College, Can Tho University, Cantho, Vietnam