On farm testing of integrated nutrient management strategies in Eastern Uganda

This paper reports on a Participatory Learning and Action Research (PLAR) process that was initiated in three villages in eastern Uganda in September 1999 to enable small-scale farmers to reverse nutrient depletion of their soils profitably by increasing their capacity to develop, adapt and use integrated natural resource management strategies. The PLAR process was also used to improve the participatory skills and tools of research and extension personnel to support this process. The farming systems of the area were characterised for socio-economic and biophysical conditions that included social organisations, wealth categories, gender, crop, soil, agro forestry and livestock production. Farmers identified soil fertility constraints, their indicators, and causes of soil fertility decline, and suggested strategies to address the problem of soil fertility decline. Soil fertility management diversity among households indicated that most farmers were not carrying out any improved soil fertility management practices, despite previous research and dissemination in the area. Following the diagnosis stage and exposure visits to other farmer groups working on integrated soil fertility projects, the farmers designed 11 experiments for on-farm testing. One hundred and twenty farmers then chose, for participatory technology development, sub-sets of these 11 experiments, based on the major agricultural constraints and the potential solutions identified and prioritised by the farmers. Quantitative and qualitative results from the testing, farmer evaluation and adaptation, training, dissemination strategies and socio-economic implications of these technologies are discussed

Electrochemical fabrication of microfluidic networks in carbon substrates

NRC publication: Ye

A glassy carbon microfluidic device for electrospray mass spectrometry

Due to the broad impact of microfabrication technology on chemistry and biology, new methods to pattern and etch a variety of materials are being explored in a number of laboratories. Here, we report the design, fabrication, and operation of a glassy carbon (GC) microchip interfaced to a nanoelectrospray ionization source and a quadrupole mass spectrometer. The method involves standard photolithographic pattern transfer to a photoresist layer and anodization of the exposed GC substrate in basic electrolyte to produce a series of channels with well-defined wall structure. The performance of the microchip was evaluated with standard polymer and peptide samples.NRC publication: N