Bioengineering techniques combine ecological principles and engineering to construct living systems that prevent erosion. This involves using living plant materials like bamboo, trees, and grasses to build structures like brush layers, hedgerows, palisades, and grass plantings. These living structures stabilize slopes, capture debris, improve soil and water quality, provide habitat, and are more effective and sustainable than conventional erosion control methods. The document provides examples of bioengineering projects in Nepal and describes various techniques and their purposes.