Produce a farmers guide on cover crops species selection, establishment, and termination

覆盖作物是未来农业政策的基石，也是新兴的“再生农业”方法的关键组成部分，这些方法承诺共同提供自然资本和人类营养。虽然它们可以提供多种农艺和环境效益，从通过提高土壤健康和恢复能力来增加产量，到减少农场排放/投入和增加碳捕获和生物多样性，但它们做到这一点的能力取决于背景，并取决于选择能够在特定播种田地条件下表现的物种。种子选择建议可以通过供应商获得，但随着2020年销售约150种商业混合物(Mills等人，2020)，驾驭这个市场是具有挑战性的。适当的种子选择也只是决定覆盖作物成功的几个关键因素之一，关于建立、管理和终止技术的决定同样重要，特别是在存在实施障碍的地方(例如，在草甘膦不可终止的有机系统中，或在覆盖作物生长的窗口通常被减少的北方气候中)。因此，尽管这些技术被纳入ELMS/SFIS，并作为新兴碳交易平台的农场选择，农民在采用覆盖作物时面临着巨大的不确定性/风险，没有关于种子选择、播种、农学和终止的单一“最佳实践”建议来源。在覆盖作物生产过程的任何阶段做出的错误决定都可能导致作物歉收、浪费时间、经济损失和错失利用覆盖作物全部潜力的机会。在极端情况下，甚至可能导致“生态系统损害”，例如，一种选择不当的覆盖作物为后续经济作物的病虫害提供了一座“绿色桥梁”。因此，有机会更好地支持农民参与覆盖作物以及由此产生的农学、环境和社会经济收益。为了实现这一机会，我们建议制定一份可访问的、独立的、农民主导的和得到科学支持的“农民指南”，涵盖作物的选择、建立和终止，以给希望利用覆盖作物的农民提供信心，降低所有阶段的决策过程风险，降低不可预见的成本，并提高覆盖作物在农场的成功和吸收。重要的是，本指南将纳入在一系列最终用户情景(例如土壤组成和区域气候)中管理成功覆盖种植的外部因素，影响覆盖作物如何设计以达到最佳效果的内部驱动因素(例如轮作计划和所需覆盖作物交付成果的平衡)，以及可用于部署覆盖作物的工具，包括在具有挑战性的环境中。

Cover crops are cornerstones of future farming policy and critical components of emerging 'regenerative agriculture' approaches that promise co-delivery of natural capital and human nutrition. While they can deliver multiple agronomic and environmental benefits, from increasing yields by building soil health and resilience to reducing on-farm emissions/inputs and increasing carbon capture and biodiversity, their ability to do so is context-dependant and reliant on selecting species that can perform under conditions specific to the field in which they are sown. Seed selection advice is available through suppliers, but with ~150 commercial mixes marketed in 2020 (Mills et al, 2020), navigating this marketplace is challenging. Appropriate seed selection is also just one of several key factors governing cover crop success, with decisions regarding establishment, management and termination techniques being equally important, especially where barriers to implementation exist (e.g. in organic systems where glyphosate is unavailable for termination, or in northern climates where windows for cover crop growth are typically reduced).Consequently, despite their inclusion in ELMs/SFIs, and as on-farm options in emerging carbon-trading platforms, farmers are exposed to significant uncertainty/risk when adopting cover crops, with no single source of 'best practice' advice covering seed selection, sowing, agronomy and termination. A poor decision made at any stage in the cover crop production process can result in a failed crop, wasted time, financial loss, and a missed opportunity to leverage a cover crop's full potential. In extreme cases, 'ecosystem disservices' can even result, for example where an ill-chosen cover crop provides a 'green bridge' for pests and diseases of the subsequent cash crop.Opportunity therefore exists to better support farmers to engage with cover crops and the agronomic, environmental, and socio-economic gains that can flow from them. To realise this opportunity, we propose development of an accessible, independent, farmer-led and scientifically-supported '_Farmer's guide to cover crop selection, establishment, and termination_' to provide confidence to farmers wishing to utilise cover crops, de-risking the decision-making process at all stages, reducing unforeseen costs, and improving the success and uptake of cover crops on-farm. Importantly, this guide will embed external factors that govern successful cover cropping across a range of end-user scenarios (e.g. soil compositions and regional climates), internal drivers that influence how cover crops are designed to best effect (e.g. crop rotation plans and the balance of desired cover crop deliverables), and the tools that can be used to deploy them, including in challenging circumstances.