Assessing the Impact of No-till on Water Related Soil Functions and the Role of Farmer Networks in Knowledge Exchange and Implementation

No-tillage is a non-inversion farming practice that is becoming more widely used in farming and often considered to enhance soil functions, by increasing soil organic matter levels and thereby improving soil structure. Knowledge about the effects of different management practices on separate soil functions is important to understand potential trade-offs between them. Studies have shown that no-tillage affects soil functions of water purification and water retention and can reduce erosion rates and inputs from agriculture to water bodies, however evidence from north western European countries is still limited. Alongside this gap in evidence about the physical impacts of no-tillage, knowledge about how farmers share knowledge about no-tillage, a knowledge intensive practice, and the role of farmer networks is still growing. This paper presents results from interdisciplinary (PhD) research which measured the effect of no-tillage on water related soil functions in a UK case study and analysed the distribution of no-tillage knowledge through farmer networks. The field-scale monitoring compares two neighbouring farms (one using conventional ploughing and the other no-tillage) with similar soil and topographic characteristics to assess spatial and temporal changes in soil and water variables. The 2-year monitoring included nutrient analysis of surface and sub-surface soil samples, bulk density, soil moisture, infiltration capacity, surface runoff and analysis of Dissolved Reactive Phosphorous (DRP), Total Phosphorous (TP) and Suspended Solids (SS) in downstream waters. Farmers’ networks were mapped using Social Network Analysis (SNA) to reveal the nature and extent of their knowledge exchange about no-tillage. This was complemented by semi-structured interviews with farmers to understand their reasons for implementing no-tillage. This paper presents findings from both aspects of this research. The soil and water data show varying impacts of no-tillage on soil functions and water quality with different soil types and climate. The no-tillage fields had higher bulk density and soil organic matter content and thereby increasing the soil moisture levels, but the free-draining porous limestone was providing greater benefits under no-tillage in this study compared with the limerich loamy soil with high silt and clay content. The SNA suggests that farmers’ networks expanded with the conversion to no-tillage and that their main influencers were other more experienced no-tillage farmers. In this respect I question the role of external organisations in supporting no-tillage adoption. The research offers a significant new contribution to the field as it assesses the effects of no-tillage on water purification and retention functions of the soil, and at the same time contributes to understanding the dynamics of farmer networks and the link to implementation