In recent years, anaerobic digestion of organic waste (OW) is rapidly appearing as a winning waste management strategy by producing energy and anaerobic digestates that can be used as fertilizers in agricultural soils. In this context, the management of the OW treatment process to maximize agro-system sustainability satisfying the crop nutrient demands represents the main goal. To investigate these traits, two protocols to assess the plant availability of digestate nitrogen (N) and phosphorus (P) were evaluated. With this aim, the N and P availability was determined on 8 digestates and 2 types of digestate-based compost from different OW via sequential chemical extractions (SCE). In addition, the digestates were tested in soil incubations and in plant pot tests with Italian ryegrass and compared with chemical fertilizer and a non-amended control soil. The N extracted from digestates via SCE was related to soil N mineralization and plant N recovery. The C: N ratio had negative impact on mineralized N and its recovery in shoots (Shoots_N = −0.0085.(C/N)+0.172, r² = 0.67), whereas water extractable mineral N was positevely related to the root N apparent recovery fraction (N-ARF) with (Roots_N = 5E⁻⁵.N_solublemin+0.0138, r² = 0.53). The shoot P-ARF was positively correlated with the inorganic water extractable fraction of P (Shoots_P =0.1153.H₂O-P_i−0.2777.H₂O-P_o+0.0249, r² = 0.71) whereas the root P-ARF was positively correlated with the less accessible fractions (Roots_P = (b) 0.0955.NaHCO₃-P_o+0.0955.NaOH-P_o-0.0584NaHCO₃-P_i+0.0128, r² = 0.8641). Feedstock digestate typology impacted the N and P recovery results leading to a better description of the typology properties and a first nutrients ARF prediction.

近年来，有机废物厌氧消化（OW）通过产生可作为农业土壤肥料的能源和厌氧消化物，迅速成为一种成功的废物管理策略。在这种情况下，OW处理过程的管理可最大限度地满足农作物养分需求，从而实现农业系统的可持续性，这是主要目标。为了研究这些性状，评估了两种用于评估植物体内消化性氮（N）和磷（P）可用性的方案。以此为目标，通过顺序化学提取（SCE），确定了来自不同OW的8种消化物和2种基于消化物的堆肥的N和P利用率。此外，消化物在土壤培养中和意大利黑麦草的盆栽试验中进行了测试，并与化学肥料和未经改良的对照土壤进行了比较。通过SCE从消化物中提取的氮与土壤氮矿化和植物氮的回收有关。碳氮比对矿化氮及其在枝条中的回收有负面影响_Ñ = -0.0085。（C / N）0.172，R ²  = 0.67），而水可提取的无机氮被positevely与根氮肥表观回收百分率（N-ARF）与（罗茨_Ñ = 5E ^-5 .N _solublemin + 0.0138，r ²  = 0.53）。枝条P-ARF与P的无机水可萃取级分呈正相关（射击_P = 0.1153.H ₂ O-P _i -0.2777.H ₂ O-P _o + 0.0249，r ²  = 0.71），而根系P-ARF正相关分数较少的元素（根_P =（b）0.0955.NaHCO ₃ -P _o+ 0.0955.NaOH-P _o -0.0584NaHCO ₃ -P _i + 0.0128，r ²  ＝ 0.8641）。原料消化的类型影响了氮和磷的回收率，从而更好地描述了类型特性并首次预测了营养素ARF。