Developing plant-based strategies for the sustainable remediation of salinized soils

制定基于植物的盐化土壤可持续修复策略

• 批准号: RGPIN-2021-02430
• 负责人: Zeeb, Barbara
• 金额: $ 3.79万
• 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: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=741975
• 关键词: Developing; plant; based; strategies; sustainable

Impacts of soil and freshwater salinization are widespread and substantial. The Food and Agriculture Organization of the United Nations estimate that ~6.5% of the world's arable soils are already saline or sodic. In this proposal, phytoremediation (using plants to remediate soils) is explored as a means of mitigating the harmful effects of salt at affected sites. Salt-tolerant plants known as `halophytes' are evaluated for their potential to remediate salinized soils and prevent leaching of salts into surface and ground waters. While most plants are sensitive to salt, halophytic plants have developed mechanisms to tolerate and thrive in these conditions. `Accumulator halophytes' sequester salts in their tissues, while `recretohalophytes' secrete excess salts through specialized glands on their leaf surfaces. Both types of plants are useful in the context of phytoremediation. In the former, plants must be harvested and the salt-contaminated biomass disposed of, while in the latter, salts may be dispersed on the wind in a process referred to as `haloconduction'. This proposal will study: i) accumulator halophytes to remediate road salt on motor ways, and ii) recretohalophytes for the broader remediation of industrially salinized soils. Canada currently leads the world in salt consumption, applying >5 million tonnes of road salt annually. Greenhouse and field studies will be employed to investigate native plant species for remediation of salinized roadsides, and will determine if the harvested salt-laden plant biomass may be repurposed into useable by-products (e.g. fodder, compost, or biochar). In theory, the use of recretohalophytes has an advantage over accumulator halophytes as excreted salt may be dispersed through wind action, thus removing the need for plant harvesting. Ironically, while salts are hazardous at high concentrations, low levels are essential nutrients for both flora and fauna species, and hence may prove to be beneficial when dispersed. The focus will be on exploring Canadian recretohalophytes with the goal of providing an alternative phytotechnology for remediating salt-contaminated sites that is feasible and sustainable, while also being low-cost and easy to implement. The integration of plants into any remediation design has the benefits of minimizing soil degradation, mitigating climate change through carbon storage in plant matter, creating habitat for native species, and improving site aesthetics. Findings documenting best practices will be published, ultimately putting a new environmental technology into the hands of Canadians. Over a 5-year period, this proposal will support and train 12 HQP. HQP will gain skills in critical thinking and planning, laboratory analytical techniques, field work organization and mobilization, and communication skills (both oral and written), all of which are actively sought after by prospective employers be they academic, industrial or private sector.

土壤和淡水盐碱化的影响是广泛而重大的。联合国粮食及农业组织估计，世界上约 6.5% 的耕地已经是盐碱地或钠盐。在该提案中，探索了植物修复（使用植物修复土壤）作为减轻受影响地点盐害影响的一种手段。人们对被称为“盐生植物”的耐盐植物修复盐化土壤和防止盐浸入地表水和地下水的潜力进行了评估。虽然大多数植物对盐敏感，但盐生植物已经形成了耐受这些条件并在这些条件下茁壮成长的机制。 “累积盐生植物”将盐分封存在其组织中，而“分泌盐生植物”则通过叶表面的专门腺体分泌多余的盐分。两种类型的植物均可用于植物修复。在前者中，必须收获植物并处理受盐污染的生物质，而在后者中，盐可以通过称为“晕传导”的过程散布在风中。该提案将研究：i）蓄积盐生植物，用于修复高速公路上的路盐；ii）长生盐生植物，用于更广泛地修复工业盐化土壤。加拿大目前在盐消耗方面处于世界领先地位，每年使用超过 500 万吨路盐。将采用温室和实地研究来调查用于修复盐化路边的本地植物物种，并将确定收获的含盐植物生物质是否可以重新用于生产可用的副产品（例如饲料、堆肥或生物炭）。从理论上讲，使用泌盐植物比蓄积盐生植物具有优势，因为排泄的盐可以通过风力作用分散，从而消除了植物收获的需要。具有讽刺意味的是，虽然盐在高浓度下是危险的，但低浓度的盐却是动植物物种的必需营养素，因此分散时可能是有益的。重点将是探索加拿大的续盐植物，目标是提供一种可行、可持续、低成本且易于实施的替代植物技术来修复盐污染场地。将植物融入任何修复设计都具有以下好处：最大限度地减少土壤退化、通过植物物质中的碳储存来缓解气候变化、为本地物种创造栖息地以及改善场地美观。记录最佳实践的调查结果将被公布，最终将新的环保技术交到加拿大人手中。该提案将在 5 年时间内支持和培训 12 名总部人员。 HQP 将获得批判性思维和规划、实验室分析技术、现场工作组织和动员以及沟通技巧（口头和书面）方面的技能，所有这些技能都是未来雇主（无论是学术界、工业界还是私营部门）积极寻求的。