Assessing the Impact of Zero Tillage on Agrochemical Transport

评估零耕对农用化学品运输的影响

• 批准号: 2432066
• 金额: --
• 依托单位: University of Nottingham
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2020
• 资助国家: 英国
• 起止时间: 2020 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2432066
• 关键词: Assessing; Impact; Zero; Tillage; Agrochemical

Soil is the most complex biomaterial on earth, yet our understanding of how its form influences its function is still poorly understood. This is large due to our inability to observe what is happening underground as soil is opaque. However, new methods to image soil systems, using tools such as X-ray Computed Tomography now provide a means to explore this hidden underworld. Soil is the largest land-based reservoir of carbon on Earth. Changes in the management of agricultural soils can affect their role as a source or sink in the global carbon cycle, and the scale and composition of their greenhouse gas emissions. Conservation Agriculture approaches such as those that reduce cultivation are gathering pace in adoption globally. There is increasing evidence that by reducing or ceasing to plough (i.e. zero tillage), a soil structure evolves, over time, which improves soil health/quality whilst maintaining crop yield. Recent data has shown there are also advantages in terms of reduced greenhouse gas emissions and enhanced carbon sequestration. While the adoption of zero tillage in N. & S. America has been rapid, Europe, and in particular, the UK, has been slower to respond with currently only c. 50% under min tillage and around 10% under zero tillage. Evidence that outlines the implications for the adoption of zero tillage in the UK is urgently needed. New evidence that outlines the implications for the adoption of zero tillage in the UK is urgently needed.A key area not yet assessed is the impact of tillage on the bio-performance of soil applied agrochemicals despite empirical evidence from the field indicating product performance is indeed affected. Zero tillage substantially increases bulk density and subsequently decreases soil porosity which impacts negatively on the infiltration of water and solutes, including agrochemicals. However, the impact of leaving the soil undisturbed is the development of a soil structure, over time, driven by the soil fauna. This structure has a reduced porosity compared to ploughed soil but a comparable pore connectivity which is the most important property for soil hydraulic function.The overarching aim is to illustrate how, and over what time scales, soil structure obtained under zero tillage impacts on agrochemical product performance. In partnership with Syngenta, and using a combination of field and laboratory work, key questions that this exciting PhD project will assess include: i) What is the impact of the soil structure imposed by zero tillage on the distribution and movement of agrochemicals in soil; ii) To what extent are differences persistent across soil types; iii) How do differences in soil structure affect the bio-performance of agrochemicals and iv) At what point, if any, in the conversion from conventional to zero tillage do soil hydraulic properties favour optimum availability of agrochemicals in soils.

土壤是地球上最复杂的生物材料，但我们对它的形式如何影响其功能的理解仍然知之甚少。这是因为我们无法观察到地下发生了什么，因为土壤是不透明的。然而，使用X射线计算机断层扫描等工具对土壤系统进行成像的新方法现在提供了一种探索这种隐藏的地下世界的手段。土壤是地球上最大的陆地碳库。农业土壤管理的变化可能影响其在全球碳循环中作为源或汇的作用，以及其温室气体排放的规模和组成。减少种植等保护性农业方法正在全球范围内加快采用步伐。越来越多的证据表明，通过减少或停止耕作（即免耕），土壤结构会随着时间的推移而演变，从而改善土壤健康/质量，同时保持作物产量。最近的数据表明，在减少温室气体排放和加强碳固存方面也有优势。而免耕在N. & S.美国已经迅速，欧洲，特别是英国，反应较慢，目前只有c。少耕50%左右，免耕10%左右。迫切需要证据来说明英国采用免耕的影响。英国迫切需要新的证据来概述采用免耕的影响。一个尚未评估的关键领域是耕作对土壤施用农用化学品的生物性能的影响，尽管来自实地的经验证据表明产品性能确实受到影响。免耕法大大增加了容重，从而降低了土壤孔隙度，这对水和溶质（包括农用化学品）的渗透产生了不利影响。然而，保持土壤不受干扰的影响是土壤结构的发展，随着时间的推移，由土壤动物驱动。这种结构有一个减少的孔隙度相比，翻耕土壤，但一个可比的孔隙连通性，这是最重要的属性土壤水力function.The首要的目的是说明如何，以及在什么样的时间尺度下，土壤结构得到免耕农化产品性能的影响。通过与先正达的合作，并结合实地和实验室工作，这个令人兴奋的博士项目将评估的关键问题包括：i）免耕对土壤中农用化学品的分布和移动造成的土壤结构的影响; ii）不同土壤类型之间的差异在多大程度上是持久的; iii）土壤结构的差异如何影响农用化学品的生物性能; iv）在从传统耕作到免耕的转换中，土壤水力特性在什么时候（如果有的话）有利于土壤中农用化学品的最佳可用性。