NEIKER, Department of Conservation of Natural Resources, Soil Microbial Ecology Group, c/ Berreaga 1, E-48160, Derio, Spain.
Department of Biochemistry and Molecular Biology, Instituto BIOFISIKA (CSIC, UPV/EHU), University of the Basque Country, P.O. Box 644, 48080, Bilbao, Spain.
J Environ Manage. 2020 Jun 15;264:110422. doi: 10.1016/j.jenvman.2020.110422. Epub 2020 Mar 20.
The anaerobic decomposition of organic wastes might lead to the formation of organic-byproducts which can then be successfully used as organic fertilizers. This study evaluated the impact of the application of two fermented liquid organic amendments (commercial vs. farm-made) at two doses of application (optimal vs. suboptimal), compared to mineral fertilization, on lettuce growth and soil quality. To this purpose, two experiments were conducted at microcosm- and field-scale, respectively. In the microcosm experiment, organically amended soils resulted in lower lettuce yield than minerally fertilized soil but, in contrast, they enhanced microbial activity and biomass, thus leading to an improvement in soil quality. The fertilization regime (organic vs. inorganic) significantly affected soil microbial composition but did not have any significant effect on structural or functional prokaryotic diversity. In the field experiment, at the optimal dose of application, organically-amended soils resulted in comparable lettuce yield to that displayed by minerally fertilized soils. The application of organic amendments did not result in an enhanced microbial activity and biomass, compared to mineral fertilization, but led to a higher soil prokaryotic diversity. Among the organically-amended plots, the optimal application dose resulted in a higher lettuce yield and soil microbial activity and biomass, but led to a decline in soil prokaryotic diversity, compared to the suboptimal application dose. Our results indicate that commercial and farm-made fermented liquid organic amendments possess the potential to ameliorate soil quality while sustaining crop yield. Given the strong influence of other factors (e.g., type of soil, dose of application) on the effects exerted by such amendments on soil quality and fertility, we recommend that an exhaustive characterization of both the amendments and the recipient soils should be carried out prior to their application, in order to better ensure their potential beneficial effects.
有机废物的厌氧分解可能导致有机副产物的形成，这些副产物随后可以成功地用作有机肥料。本研究评估了两种发酵液体有机改良剂（商业与农家自制）在两种施用量（最佳与次佳）下，与矿物施肥相比，对生菜生长和土壤质量的影响。为此，分别在微宇宙和田间尺度进行了两项实验。在微宇宙实验中，有机改良土壤导致生菜产量低于矿物施肥土壤，但与矿物施肥相比，它们增强了微生物活性和生物量，从而改善了土壤质量。施肥制度（有机与无机）显著影响土壤微生物组成，但对结构或功能原核生物多样性没有任何显著影响。在田间实验中，在最佳施用量下，有机改良土壤的生菜产量可与矿物施肥土壤相媲美。与矿物施肥相比，有机改良剂的应用并未导致微生物活性和生物量的增强，但导致土壤原核生物多样性增加。在有机改良剂处理的地块中，与次佳施用量相比，最佳施用量导致生菜产量和土壤微生物活性及生物量更高，但导致土壤原核生物多样性下降。我们的结果表明，商业和农家自制发酵液体有机改良剂具有改善土壤质量同时维持作物产量的潜力。鉴于其他因素（例如土壤类型、施用量）对这些改良剂对土壤质量和肥力的影响具有强烈影响，我们建议在应用这些改良剂之前，应对改良剂和受纳土壤进行详尽的特性描述，以更好地确保其潜在的有益效果。
