Enhancing the understanding and assessment of soil erosion and sedimentation through improvements to tracer techniques

土壤侵蚀和沉积(SES)仍然是加拿大和世界各地的主要环境问题。土壤侵蚀使土壤质量下降，由此产生的沉积物使水质和空气质量下降。事实证明，示踪剂在衡量SES、加强对这些过程的了解以及为其评估和预测开发模型方面是宝贵的工具。在这些示踪剂中，放射性沉降物137Cs和210Pb在监测农田内土壤和沉积物的再分布以及追踪和获取农业流域内的沉积物方面非常有效，这项技术被称为沉积物指纹。拟议研究的总体目标是改进使用示踪剂评估SES的技术。一组协调和互补的研究项目将审查农业景观和流域土壤和沉积物的时空特性的性质，重点是用于评估海洋生态系统的示踪剂。将在两个流域，一个在马尼托巴省，另一个在新不伦瑞克，研究水道和水体中沉积物性质的变异性。将在与这些分水岭相关的两块耕地上研究景观中土壤性质的变异性。将评估创新技术和技术，例如使用便携式伽马能谱仪在实地测量FRN，以及使用新的和新的FRN组合，以确定它们是否能够提供更有效的土壤和沉积物采样战略，并提供更有效的手段，将SES结果内插到景观和流域中。对空间和时间变异性及其原因(固有的/自然的和诱发的/人为的原因)有更多认识的抽样战略预计将大大减少与SES测量相关的不确定性。预计与SES测量相关的误差可以减半，这是现实的。通过研究土壤和沉积物的空间和时间变异性获得的洞察力将加强对土壤侵蚀(土壤流失和积累)和沉积(生产、运输、行为和命运)的理解。更多的信息和更可靠的衡量标准将增加对SES评估的信心。预计更大的信心将导致制定更有效的政策和方案，并更广泛地使用有效的水土保持做法，从而增强我们土地和水资源的可持续性。在很大程度上，这一影响将通过培训各级土地和水资源研究和管理方面的专业人员来实现。拟议的研究将为两名博士生、两名硕士学生和八名本科生提供培训。

Soil erosion and sedimentation (SES) continue to be major environmental concerns in Canada and around the world. Soil erosion degrades soil quality, and the resulting sediment degrades water quality and air quality. Tracers have proven to be valuable tools in measuring SES, enhancing the understanding of these processes, and developing models for their assessment and prediction. Of these tracers, the fallout radionuclides (FRNs) 137Cs and 210Pb have been very effective in monitoring the redistribution of soil and sediment within agricultural fields, and in tracking and sourcing sediments within agricultural watersheds, a technique known as sediment fingerprinting. The general objective of the proposed research is to improve techniques used to assess SES using tracers. A coordinated and complementary group of research projects will examine the nature of spatial and temporal properties of soil and sediment in agricultural landscapes and watersheds, focusing on tracers used in the assessment of SES. The variability of sediment properties in waterways and water bodies will be studied in two watersheds, one in Manitoba and the other in New Brunswick. The variability of soil properties in landscapes will be studied in two cultivated fields associated with each of these watersheds. Innovative technologies and techniques, such as the use of portable gamma spectrometers to measure FRNs in the field and the use of new and new combinations of FRNs, will be evaluated for their ability to provide more effective soil and sediment sampling strategies and to provide a more effective means of interpolating SES results across landscapes and watersheds. Sampling strategies that employ a greater awareness of spatial and temporal variability and their causes (inherent/natural and induced/anthropogenic causes) are expected to lead to substantial decreases in the uncertainties associated with SES measurements. It is realistic to expect that the errors associated with SES measurements could be cut in half. The insights gained by examining the spatial and temporal variability of soils and sediments will enhance the understanding of soil erosion (soil loss and accumulation) and sedimentation (production, transport, behaviour and fate). More informed and more reliable measurements will increase confidence in SES assessments. Greater confidence is expected to lead to the development of more effective policies and programs, and to more widespread use of effective soil and water conservation practices, and, in doing so, enhance the sustainability of our land and water resources. In no small part, this impact will be achieved by training professionals at all levels in land and water resources research and management. The proposed research will provide training for two PhD students, two MSc students and eight undergraduate students.