Departamento de Edafología y Química Agrícola, Universidad de Granada, Spain.
Waste Manag. 2010 Oct;30(10):1957-65. doi: 10.1016/j.wasman.2010.04.030. Epub 2010 May 23.
The effect of co-compost application from sewage sludge and pruning waste, on quality and quantity of soil organic carbon (SOC) in four Mediterranean agricultural soils (South Spain), was studied in soil microcosm conditions. Control soil samples (no co-compost addition) and soils treated with co-composts to a rate equivalent of 140 Mg ha(-1) were incubated for 90 days at two temperatures: 5 and 35 degrees C. The significances of incubation temperature and the addition of co-compost, on the evolution of the different fractions of SOC, were studied using a 2(3) factorial design. The co-compost amendment increased the amounts of humic fractions: humic acids (HA) (1.9 times), fulvic acids (FA) (3.3 times), humin (1.5 times), as well as the free organic matter (1.4 times) and free lipids (21.8 times). Incubation of the soils enhanced its biological activity mainly in the amended soils and at 35 degrees C, leading to progressive SOC mineralization and humification, concomitant to the preferential accumulation of HA. The incubation results show large differences depending on temperature and soil types. This fact allows us to select suitable organic amendment for the soil when a rapid increase in nutrients through mineralization is preferred, or in cases intending the stabilization and preservation of the SOC through a process of humification. In soils with HA of more than 5 E(4)/E(6) ratio, the incubation temperature increased rates of mineralization and humification, whereas lower temperatures limited the extent of both processes. In these soils the addition of co-compost in spring or summer is the most recommendable. In soils with HA of lower E(4)/E(6) ratio (<5), the higher temperature favoured mineralization but not humification, whereas the low temperature maintained the SOC levels and even increased the HA/FA ratio. In these soils the moment of addition of organic amendment should be decided depending on the effect intended. On the other hand, the lower the SOC content in the original soil, the greater are the changes observed in the SOC after amendment with co-compost. The results suggest that proper recommendations for optimum organic matter evolution after soil amendment is possible after considering a small set of characteristics of soil and the corresponding soil organic matter fractions, in particular HA.
本研究采用土壤微宇宙法，以西班牙南部四个地中海农业土壤为例，研究了污水污泥和修剪废物混合堆肥施加对土壤有机碳（SOC）质量和数量的影响。在控制土壤样品（未添加混合堆肥）和添加混合堆肥至相当于 140 Mg ha(-1)的土壤中，分别在 5 和 35°C 下进行 90 天的培养。采用 2(3)析因设计研究了培养温度和混合堆肥添加对 SOC 不同组分演变的显著性。混合堆肥的添加增加了腐殖质组分的含量：腐殖酸（HA）（1.9 倍）、富里酸（FA）（3.3 倍）、腐殖质（1.5 倍）、游离有机物质（1.4 倍）和游离脂质（21.8 倍）。土壤培养主要增强了添加混合堆肥的土壤的生物活性，并且在 35°C 下，导致 SOC 矿化和腐殖化的逐渐进行，同时优先积累 HA。培养结果表明，由于温度和土壤类型的差异，培养结果存在很大差异。这一事实允许我们根据需要通过矿化快速增加养分，或者在通过腐殖化稳定和保存 SOC 的情况下，选择合适的有机肥料。在 HA 比值大于 5 E(4)/E(6)的土壤中，培养温度增加了矿化和腐殖化的速率，而较低的温度限制了这两个过程的范围。在这些土壤中，混合堆肥的添加最好在春季或夏季进行。在 HA 比值较低（<5）的土壤中，高温有利于矿化但不利于腐殖化，而低温则保持 SOC 水平甚至增加 HA/FA 比值。在这些土壤中，添加有机肥料的时机应根据预期的效果来决定。另一方面，原始土壤中的 SOC 含量越低，添加混合堆肥后 SOC 发生的变化就越大。结果表明，在考虑土壤的一小部分特性和相应的土壤有机物质组分（特别是 HA）后，可能会对土壤添加有机物质后的最佳有机物演变提出适当的建议。
