Understanding management effects on soil organic matter and ecological function in forage-based agroecosystems.

了解管理对以饲料为基础的农业生态系统中土壤有机质和生态功能的影响。

• 批准号: RGPIN-2021-03456
• 负责人: Schneider, Kimberley
• 金额: $ 1.82万
• 依托单位: University of Guelph
• 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=742564
• 关键词: Understanding; management; effects; soil; organic

The world's soils, are increasingly being acknowledged for their potential contribution to the fight against climate change, nutrient pollution, and to provide other critical ecosystem services. Cropping systems that include forage and service crops (pasture, hay, cover crops) are known to increase carbon sequestration and provide numerous benefits to soil health and nutrient cycling. In particular, grazed agricultural grasslands show much potential for sequestering carbon by increasing belowground biomass; for example, some studies have indicated that net negative greenhouse gas emissions are possible for a predominantly grass-fed beef operation, when rotational grazing (where livestock are rotated frequently through paddocks, and allowing adequate rest periods) is employed. An improved understanding of how grazing management and pasture fertilization impact soil carbon sequestration is required in order to better contribute to climate change mitigation.   The objectives of this proposal are to determine the agro-ecological benefits provided by forage and service crops and to identify management practices that increase these benefits. In particular, I will focus on grazing management in beef production systems and how rotational grazing strategies and nitrogen fertility management can impact carbon sequestration. My research will examine the quality of the soil organic matter in order to better understand its ecological function (how stable it is, etc.). I will also quantify the soil health benefits provided by including perennial forage in a cropping system rotation in terms of the ability to lower fertility recommendations for a subsequent crop. These research questions will be accomplished through a combination of on-farm, controlled environment, and research station studies. My research program will provide data that will further scientific understanding on the mechanisms enhancing carbon sequestration in grazed ecosystems and make recommendations to enable improved soil carbon management in grazed soils. This research is expected to improve the environmental outcomes of the beef industry by identifying grazing management strategies that improve their productivity and ecological impacts (carbon sequestration) at the same time. This is important because the beef industry is frequently under scrutiny for being a major greenhouse gas contributor, but contributions to soil carbon sequestration during grazing are typically not considered. Finally, improvements in soil quality due to the use of forage-based cropping systems that promote soil organic matter and soil health are expected to have implications for the amount of nutrients that are needed to be applied as fertilizers. Practices that may reduce the amount of nutrients, particularly P, required in agriculture are needed; this is a current cross-sector priority, and critical for the health of the Lake Erie watershed.

世界土壤因其对应对气候变化、营养物污染以及提供其他重要生态系统服务的潜在贡献而日益得到认可。众所周知，包括饲料和服务作物（牧草、干草、覆盖作物）在内的耕作系统可以增加碳固存，并为土壤健康和养分循环带来诸多好处。特别是，放牧的农业草地通过增加地下生物量显示出固碳的巨大潜力；例如，一些研究表明，当采用轮牧（牲畜经常在围场间轮换，并留出足够的休息时间）时，主要以草饲牛肉为主的经营活动可能会产生温室气体净负排放。为了更好地缓解气候变化，需要更好地了解放牧管理和牧场施肥如何影响土壤碳固存。   该提案的目标是确定饲料和服务作物提供的农业生态效益，并确定增加这些效益的管理实践。我将特别关注牛肉生产系统中的放牧管理，以及轮牧策略和氮肥管理如何影响碳固存。我的研究将检查土壤有机质的质量，以便更好地了解其生态功能（其稳定性如何等）。我还将根据降低后续作物肥力建议的能力来量化将多年生牧草纳入轮作制度所带来的土壤健康效益。这些研究问题将通过农场、受控环境和研究站研究的结合来完成。 我的研究计划将提供数据，以进一步科学理解增强放牧生态系统碳固存的机制，并提出建议，以改善放牧土壤的碳管理。这项研究预计将通过确定同时提高生产力和生态影响（碳封存）的放牧管理策略来改善牛肉业的环境成果。这一点很重要，因为牛肉行业经常因温室气体的主要贡献者而受到审查，但放牧期间对土壤碳固存的贡献通常不被考虑。最后，由于使用促进土壤有机质和土壤健康的以饲料为基础的耕作系统而改善土壤质量，预计会对作为肥料施用的养分量产生影响。需要采取可能减少农业所需养分（尤其是磷）量的做法；这是当前的跨部门优先事项，对于伊利湖流域的健康至关重要。