Watershed evaluation for sustainable use of sloping agricultural land in the southern Philippines

Project Timeframe:
May 2011 to Oct 2015

Related country(s)



Australian Centre for International Agriculture Research (ACIAR)


Commonwealth Scientific and Industrial Research Organisation (CSIRO) | Bureau of Soils and Water Management(BSWM) | Landcare Foundation of the Philippines | Department of Environment and Natural Resources (DENR) | Misamis Oriental State College of Agriculture and Technology | Bohol Island State University


Poverty in the Philippines is greatest in upland watersheds where agriculture provides the economic base. Sloping lands (≥18%) comprise an estimated 45% of the total land area in the Philippines and directly support approximately 30% of the population. Agricultural development on sloping lands is intensifying in response to increasing population and the need to diversify food and income streams.

However, sloping lands are vulnerable to erosion and degradation of watershed function, which reduces the capacity to provide vital economic benefits and ecological services. To reduce poverty there is a clear need to increase total factor agricultural productivity from sloping lands as well as to protect the watersheds where these changes are occurring. If it is to succeed, intensification and diversification of agriculture in sloping lands has to proceed through careful matching of land use to land suitability.

Agencies tasked with land use planning at watershed or community scales are therefore faced with considerable challenges in efficiently mapping the land attributes required to inform decision making. In part this challenge can met by developing appropriate digital land resource assessment techniques to provide maps of land attributes with better utility and at lower cost and combining them with rapid appraisal techniques for gathering socio-economic data.

A second challenge is to evaluate land suitability for different uses and management practices in a way that considers not only the attributes of a location but also its position in the landscape and how it is impacted by or impacts other locations. Other challenges exist in how to present spatial information so that it empowers decision makers, at both watershed and community scales, to make better informed decisions and understand conflicting demands on land.

A recent national workshop sponsored by ACIAR concluded that the nature of upland Philippines watersheds is not known well enough to allocate land use across watersheds or to guide the development of improved land management systems. A focused process of watershed characterisation, analysing the suitability of land for agricultural development, and planning land use to meet multiple social and economic objectives will guide a new phase of improved management for both productivity and sustainability.

Main activities

The aim of this project is to enable improved planning of agricultural development in upland watersheds in the southern Philippines such that agricultural production can be increased and watersheds can be protected - precursors to reducing rural poverty and improving livelihoods. This aim will be achieved through the following objectives:

  1. Develop and apply efficient methods to characterise the Cabulig (Misamis Oriental), Inabanga (Bohol) and Billabong watersheds (NSW) to include biophysical and socio-economic information, with particular emphasis on mapping land and soil attributes using digital technology. Outputs: Spatial library of important watershed attributes and efficient methods of watershed characterisation that can be used in other watersheds.
  2. Develop improved approaches to analysing the suitability of sloping land for agricultural intensification within a watershed context. Outputs: Assessment of land suitability for a variety of land uses and land management practices and methods of assessment that embrace landscape position and that can be used in other watersheds.
  3. Inform and enhance local land use planning processes at both the watershed and community scales in Cabulig and Inabanga watersheds. Outputs: Land use plans for each Philippine watershed informed by the spatial information gathered combined with local experience and technical expertise. Technical and institutional recommendations on how best to manage sloping agricultural lands in the Philippines.
  4. Design and implement on-going monitoring programs in the Philippine watersheds that allows critical assessment of the adoption and impacts of land use planning. Outputs: Establishment of monitoring/demonstration sites in each watershed as well as broader scale monitoring of adoption of alternative land uses and watershed function, that can be used to adapt planning in response to actual impacts.


  1. Scientific: Technologies for more cost effective survey of soil and land resources in upland watersheds and for better assessment of the suitability of locations for agriculture or their vulnerability to degrade watershed function.
  2. Capacity: Improved ability of Philippine agencies to: characterise watersheds, assess the suitability of land for agricultural intensification, and conduct land use planning designed to meet multiple social and economic objectives. This will enable the benefits of a wide range of previous R&D projects to be fully realised.
  3. Economic: Improved agricultural productivity in suitable areas, achieved by identification of land limitations and adoption of appropriate management systems, and better protection of vulnerable areas to avoid the costs associated with the impacts of land degradation on water quality and on damage to infrastructure due to increased prevalence of flooding.
  4. Social: Better provision of information to empower local land use planning and enable long term improvements in agricultural productivity of sloping lands and watershed condition - both key requirements for reducing rural poverty and improving livelihoods.
  5. Environmental: Better information to inform watershed planning that integrates the needs of both watershed function and community livelihoods, leading to reduced rates of soil and water degradation through better matching land use with land capability.