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.

世界上的土壤，由于其对对抗气候变化、养分污染以及提供其他关键生态系统服务的潜在贡献，正日益得到承认。众所周知，包括牧草和服务作物(牧草、干草、覆盖作物)在内的种植制度可以增加碳固存，并为土壤健康和养分循环提供许多好处。特别是，放牧的农业草原通过增加地下生物量显示出很大的封存碳的潜力；例如，一些研究表明，当采用轮牧(牲畜经常通过围场轮换，并允许足够的休息时间)时，以草饲为主的牛肉生产可能产生净负温室气体排放。需要更好地了解放牧管理和牧场施肥对土壤碳汇的影响，以便更好地为减缓气候变化作出贡献。本提案的目标是确定饲草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做法。特别是，我将重点介绍牛肉生产系统中的放牧管理，以及轮牧战略和氮肥管理如何影响碳封存。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(稳定性等)。我还将根据降低后茬作物肥力建议的能力，量化在种植制度轮作中纳入多年生牧草所提供的土壤健康益处。这些研究问题将通过农场、受控环境和研究站研究相结合的方式来完成。我的研究计划将提供数据，进一步科学理解放牧生态系统中加强碳固定的机制，并提出建议，以改善放牧土壤中的土壤碳管理。这项研究预计将通过确定同时提高生产力和生态影响(碳固存)的放牧管理战略来改善肉牛业的环境结果。这一点很重要，因为牛肉行业经常因为是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定的贡献通常不被考虑。最后，由于采用了促进土壤有机质和土壤健康的饲草型种植制度而改善了土壤质量，预计这将对需要作为肥料使用的营养素的数量产生影响。需要采取可能减少农业所需营养素，特别是磷的做法；这是当前跨部门的优先事项，对伊利湖流域的健康至关重要。