Elucidating the mechanisms utilized in phytotechnolgies and biochar immobilization to optimize contaminated site remediation

阐明植物技术和生物炭固定中使用的机制，以优化污染场地修复

• 批准号: RGPIN-2014-05611
• 负责人: Zeeb, Barbara
• 金额: $ 1.6万
• 依托单位: Royal Military College of Canada
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=636646
• 关键词: Elucidating; mechanisms; utilized; phytotechnolgies; biochar

Persistent organic pollutants (POPs) are recalcitrant contaminants known to cause a number of ecological and human health effects. Soil salinity is an escalating problem due to current agricultural practices and industrial processes, and is one of the major abiotic stresses that affect plant growth and yield. Similarly, contamination with petroleum hydrocarbons (PHCs) is at the forefront of many Canadians minds given the escalation in activity in the oil and gas industry in Canada in recent decades. Each of these contaminants can be addressed, at least to some extent, using innovative plant-based techniques known as ‘phytotechnologies’ (or phytoremediation). Phytoextraction is a specific phytotechnology whereby contaminants are taken up by plant roots, translocated to the shoots, and then sequestered in the above-ground plant tissue. Plants are then harvested and undergo biomass reduction (e.g. composting), with the goal being to significantly reduce the total volume of contaminated waste, while leaving the soil matrix intact. In the past six years, my group has made several significant advances in the area of contaminant phytoextraction, including the use of native colonizers. During the same time period, we have pioneered the use of biochar (a charcoal like material produced from the pyrolysis of organic matter under very low oxygen conditions) to decrease the bioavailability of contaminants in soils, reducing their risk to environmental and human health, and at the same time improving soil quality and decreasing CO2 emissions. These innovative techniques are now starting to be utilized more widely, however, a fundamental understanding of the processes involved in contaminant uptake into plants, and stabilization within soils is still lacking, as is the role that biochar plays in soil microbial communities and in the health of plants. This proposal will address these shortcomings and further our understanding of the mechanisms of phytoextraction. We will use methods developed by my group, such as measuring contaminants in the xylem sap of native plants at varying distances from the root. The application of community-level physiological profiling (CLPP) to obtain phenotypic information regarding microbial community function in contaminated soils alone, and those amended with biochar, is another innovative tool developed by my group. The novel use of these emerging techniques in combination with greenhouse trials employing real soil and plant systems will broaden our understanding of interactions between soil contaminants, plants, and the microbial community. Carrying out this critical phytoextraction work in combination with biochar amendment to the soil, will provide us with a deeper appreciation of the mechanisms involved in contaminant uptake and mobility within plants, and allow us to examine important changes in the microbial soil population. This will lead to our ability to also enhance the degradation of contaminants, in particular PHCs, in the root zone of phytoextraction plots. Hence, using established phytoextraction and carbon amendment immobilization techniques (combined with the emerging methods of xylem sap analysis, CLPP and biochar), this proposal will explore the efficacy of using these technologies simultaneously to remediate POPs-, salt-, and PHC-impacted sites. Ultimately, the goal of this work is to determine how phytotechnologies in conjunction with biochar can best interact to optimize contaminated site remediation. In so doing, these technologies will become more accepted and mainstream, providing contaminated site owners, government legislatures, and environmental consultants with the information they need to incorporate them into their ‘toolbox’ when remediating contaminated sites.

持久性有机污染物（POPs）是一种具有生物毒性的污染物，对生态和人类健康具有重要影响。土壤盐渍化是当前农业实践和工业过程中日益严重的问题，是影响植物生长和产量的主要非生物胁迫之一。同样，由于近几十年来加拿大石油和天然气行业活动的升级，石油碳氢化合物（PHCs）的污染是许多加拿大人最关心的问题。这些污染物中的每一种至少在某种程度上都可以使用称为“植物技术”（或植物修复）的创新植物技术来解决。植物提取是一种特殊的植物技术，其中污染物被植物根部吸收，转移到芽中，然后隔离在地上植物组织中。然后收获植物并进行生物量减少（例如堆肥），目标是显着减少受污染废物的总量，同时保持土壤基质完整。在过去的六年里，我的团队在污染物植物提取领域取得了几项重大进展，包括使用本土殖民者。在同一时期，我们率先使用生物炭（一种在低氧条件下热解有机物产生的木炭状材料）来降低土壤中污染物的生物利用度，降低其对环境和人类健康的风险，同时改善土壤质量并减少二氧化碳排放。这些创新技术现在开始被更广泛地利用，然而，对植物吸收污染物的过程以及土壤中的稳定性仍然缺乏基本的理解，生物炭在土壤微生物群落和植物健康中的作用也是如此。这一建议将解决这些缺点，并进一步了解植物提取的机制。我们将使用我的小组开发的方法，例如测量距离根部不同距离的原生植物木质部汁液中的污染物。社区水平的生理分析（CLPP）的应用，以获得有关微生物群落功能的表型信息，在污染的土壤中，单独的，那些修改与生物炭，是另一个创新的工具，由我的小组开发。这些新兴技术的新用途与温室试验相结合，采用真实的土壤和植物系统，将扩大我们对土壤污染物，植物和微生物群落之间的相互作用的理解。结合生物炭对土壤的改良，进行这一关键的植物提取工作，将使我们更深入地了解植物内污染物吸收和流动的机制，并使我们能够研究微生物土壤种群的重要变化。这将使我们有能力提高植物提取地块根区污染物的降解，特别是PHCs。因此，本提案将利用现有的植物提取和碳修正固定技术（结合木质部汁液分析、CLPP和生物炭等新兴方法），探讨同时使用这些技术对受持久性有机污染物、盐和有害生物影响的场地进行补救的有效性。最终，这项工作的目标是确定植物技术与生物炭如何最好地相互作用，以优化污染场地的修复。这样，这些技术将变得更加被接受和主流化，为污染场地所有者、政府立法机构和环境顾问提供所需的信息，以便在修复污染场地时将其纳入他们的“工具箱”。