García-Gómez Antonio, Bernal María Pilar, Roig Asunción
Department of Soil and Water Conservation and Organic Waste Management, Centro de Edafología y Biología Aplicada del Segura, CSIC, PO Box 4195, 30080 Murcia, Spain.
Waste Manag Res. 2003 Apr;21(2):161-71. doi: 10.1177/0734242X0302100210.
The carbon and nitrogen mineralisation of a composting mixture of brewing yeast and lemon tree prunings was studied, at different degrees of stabilisation of this matrix, within an incubation experiment in soil. Meanwhile, a growth test in pots with ryegrass (Lolium perenne L.) was carried out using the selected soil and equal amounts of the composting mixture taken at different maturation steps, in order to evaluate the additions of these organic amendments in terms of fertilising value. Samples of the composting mixture, when poorly transformed through the biostabilisation process, showed high CO2-C releases in the soil, due to the microbial attack on easily degradable organic fractions still present in the mixture, with 24.7% mineralisation of the initial total organic carbon (TOC) after a 70 day incubation. On the other hand, mature compost was the most stable matrix, with only 5.4% of TOC mineralised after 70 days. Furthermore, amendments with the initial composting mixture led to negative net N-mineralisation during 56 days of incubation with soil. Only slight negative values of the net N-mineralisation were detected with fully stabilised compost. Nevertheless, pot experiments with ryegrass revealed that mature compost may promote N mineralisation to certain extents. Moreover, mature compost did not produce any phytotoxic effect, behaving as a slow-action organic fertiliser with N made available through a progressive mineralisation. Thus, the results gained through this study are a confirmation that the fertilising quality of a compost destined for agricultural uses is heavily affected by the complete exhaustion of the maturation reactions.
在土壤培养试验中，研究了啤酒酵母与柠檬树修剪枝条堆肥混合物在不同稳定程度下的碳氮矿化情况。同时，使用选定的土壤和取自不同成熟阶段等量的堆肥混合物，在装有黑麦草（Lolium perenne L.）的花盆中进行生长试验，以评估这些有机改良剂在施肥价值方面的添加效果。堆肥混合物样品在生物稳定化过程中转化程度较低时，由于微生物对混合物中仍存在的易降解有机组分的攻击，在土壤中表现出较高的CO2-C释放量，70天培养后初始总有机碳（TOC）的矿化率为24.7%。另一方面，成熟堆肥是最稳定的基质，70天后TOC的矿化率仅为5.4%。此外，用初始堆肥混合物进行改良在与土壤培养56天期间导致负净氮矿化。使用完全稳定化的堆肥仅检测到轻微的负净氮矿化值。然而，黑麦草盆栽试验表明，成熟堆肥在一定程度上可能促进氮矿化。此外，成熟堆肥没有产生任何植物毒性作用，表现为一种通过渐进矿化提供氮的缓释有机肥料。因此，通过本研究获得的结果证实，用于农业用途的堆肥的施肥质量受到成熟反应完全耗尽的严重影响。
