Centro de Investigación y Desarrollo en Fermentaciones Industriales (CINDEFI), CONICET- UNLP, La Plata, Argentina.
Centro de Investigación de Fitopatologías (CIDEFI), CICBA - UNLP, La Plata, Argentina.
Biodegradation. 2021 Apr;32(2):145-163. doi: 10.1007/s10532-021-09929-y. Epub 2021 Feb 13.
Soil is the recipient of organic pollutants as a consequence of anthropogenic activities. Hydrocarbons are contaminants that pose a risk to human and environmental health. Bioremediation of aging contaminated soils is a challenge due to the low biodegradability of contaminants as a result of their interaction with the soil matrix. The aim of this work was to evaluate the effect of both composting and the addition of mature compost on a soil chronically contaminated with hydrocarbons, focusing mainly on the recovery of soil functions and transformations of the soil matrix as well as microbial community shifts. The initial pollution level was 214 ppm of polycyclic aromatic hydrocarbons (PAHs) and 2500 ppm of aliphatic hydrocarbons (AHs). Composting and compost addition produced changes on soil matrix that promoted the release of PAHs (5.7 and 15 % respectively) but not the net PAH elimination. Interestingly, composting stimulated AHs elimination (about 24 %). The lack of PAHs elimination could be attributed to the insufficient PAHs content to stimulate the microbial degrading capacity, and the preferential consumption of easily absorbed C sources by the bacterial community. Despite the low PAH catabolic potential of the aging soil, metabolic shift was driven by the addition of organic matter, which could be monitored by the ratio of Proteobacteria to Actinobacteria combined with E/E ratio. Regarding the quality of the soil, the nutrients provided by the exogenous organic matter contributed to the recovery of the global functions and species diversity of the soil along with the reduction of phytotoxicity.
土壤是人为活动造成的有机污染物的受体。碳氢化合物是对人类健康和环境造成危害的污染物。由于污染物与土壤基质相互作用而导致其生物降解性降低，老化污染土壤的生物修复是一个挑战。这项工作的目的是评估堆肥和添加成熟堆肥对长期受碳氢化合物污染土壤的影响，主要集中在恢复土壤功能和土壤基质转化以及微生物群落变化上。初始污染水平为多环芳烃 (PAHs)214ppm 和脂肪族烃 (AHs)2500ppm。堆肥和添加堆肥会改变土壤基质，促进 PAHs 的释放（分别为 5.7%和 15%），但不会导致 PAHs 的净消除。有趣的是，堆肥刺激了 AHs 的消除（约 24%）。PAHs 消除不足可能归因于微生物降解能力不足的 PAHs 含量以及细菌群落对易吸收 C 源的优先消耗。尽管老化土壤的 PAH 代谢潜力较低，但通过添加有机物可以驱动代谢转变，这可以通过结合 E/E 比监测变形菌门与放线菌门的比值来监测。关于土壤质量，外源有机物提供的养分有助于恢复土壤的整体功能和物种多样性，并降低植物毒性。
