"This book is based on research conducted in the research project "HOlistic and Sustainable Abatement of Noise by optimized combinations of Natural and Artificial means" (HOSANNA). The project aimed to develop a set of tools for reducing road and rail traffic noise in outdoor environments by the optimal use of vegetation, soil, other natural materials and recycled materials in combination with artificial elements. The project studied a number of green abatement strategies that might achieve cost-effective improvements using new barrier designs, planting of trees, shrubs, or bushes, ground and road surface treatments, and greening of building facades and roofs. The noise reduction was assessed in terms of sound level reductions, perceptual effects, and cost-benefit analyses"--Provided by publisher.