Energy farming in Dutch desiccation abatement areas: yields and benefits compared to grass cultivation

Measures to combat desiccation of Dutch nature reserves often lead to the e stablishment of buffer areas around them, in which soils become moisture, a nd agricultural yields decrease. Cultivation of the flooding-tolerant energ y crop willow may be an alternative in such areas. In this study, the perfo rmance of willow production is compared to that of grass for roughage. The effect of high groundwater tables on yields of both crops is estimated usin g the agro-hydrological model SWAP. Financial consequences are evaluated by calculating the biomass price that, for a farmer, makes willow equally com petitive as grass. At groundwater table class (Gt) II, common in buffer are as, willow physical yield is ca. 15% lower than its optimum, but grass yiel d decreases by ca. 25%, making willow more competitive. This results in a 2 0% lower break-even willow price on Gt II than in a drier, optimal situatio n. A sensitivity analysis shows that most parameters with a strong influenc e on the break-even willow price have reasonably high certainty. An uncerta in value with strong influence is the willow yield without hydrological con straints, which could not be estimated from practical data. Methodological limitations of the study, both in the financial comparison between willow a nd grass, and in the yield estimations, are also discussed. (C) 2001 Elsevi er Science Ltd, All rights reserved.