Plant-based biogas production for improved nutrient management of beetroot in stockless organic farming

摘要: Transition from a nutrient management system based on green manure (GrM system) to one biodigested plant material produced within the crop rotation (BG was investigated in sequences including clover-grass, beetroot and cereals. The overall hypothesis that transition would improve nitrogen (N) availability. In field experiments sandy soil, harvested clover-grass ley had lower N content clover biomass than GrM-ley. residual effect of clover-grass ley twice (2H) or three times (3H) 42 74 kg ha-1 less GrM-ley considering uptake beetroot mineral soil at harvest. Expressed as inorganic fertiliser equivalents reduction 52 80 ha-1, respectively. Net (from effluent plus pre-crops) were simulated for sequences: (A) ley, beetroot, winter rye; (B) (C) harvested ley, spring barley, where B C represented BG systems A GrM system. For hectares with entire sequence A, C, net 73, 128 N, 2H- 3H-ley did not differ significantly. When whole increase used following marketable yield increased by 1.7 Mg (12%) 2H-ley 5.8 (34%) compared grown without digestate fertilisation Fertilisation moderate level directly gave unexpectedly low responses. Compositional diagnosis (CND) using norms derived aeroponic 22 treatments dynamic supply partial least squares (PLS) synonymous showing K more growth-limiting N at early growth stages. Growth limitation severe effluent-fertilised barley. Pot showed an apparent mineralisation organically bound 12%. conclusion can greatly efficiency. However, buffering capacity is low, inappropriate use effluent, e.g. unsuitable point rotation, negate efficiency benefits.