Ineffective water catchment policy and practice is contributing to insecure food sources and uncertain livelihoods in regional areas of eastern Indonesia.
On a recent visit to Nusa Tenggara Timur, Charles Darwin University’s Research Institute for the Environment and Livelihoods Senior Research Fellow Dr Bronwyn Myers led a water catchment workshop to resolve these issues.
Dr Myers said current water catchment practices could be improved by incorporating sound research and data into management plans.
“Eastern Indonesia has a tropical wet-dry climate and water is limiting factor for food production,” Dr Myers said.
“Locals experience a ‘hungry season’ every year because most people depend on subsistence agriculture and it is only possible to harvest one crop per year.
“Rice fields in the lower catchment are irrigated from weirs but the weir pools and irrigation channels are continually filling with sediment.
“The major catchments in the region are classed as critical because they are highly erodible and have high levels of sedimentation.”
Dr Myers said land use practices that contribute to erosion, such as disturbance to riverside vegetation, fire and artisanal mining (small scale mining done by hand), add to catchment sediment levels.
“Sediment levels can be managed through land use and erosion prevention strategies, such as fencing, to protect river bank vegetation,” Dr Myers said.
Current government policy is guided by the assumption that sediment originates from erosion in upper catchment, and the strategy to correct this is to plant trees there.
“Water catchment research by CDU’s PhD student Sarah Hobgen in eastern Indonesia has shown that sediment comes from not only the upper, but also the lower and mid catchment, caused by landslides, gullying and channel bank erosion,” Dr Myers said.
The workshop was attended by representatives from local universities, government and non-government organisations and funded by the Crawford Fund.