Kamilla Skaalsveen

Research Scientist

(+47) 988 22 515
kamilla.skaalsveen@nibio.no

Place
Ås O43

Visiting address
Oluf Thesens vei 43, 1433 Ås

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Abstract

There are still uncertainties regarding the long-term impact of no-tillage farming practices on separate soil functions in the United Kingdom. This paper aimed to evaluate the chemical and physical processes in two different agricultural soils under no-tillage and conventional management practices to determine their impact on water related soil functions at field scale in the United Kingdom. The field-scale monitoring compares two neighboring farms with similar soil and topographic characteristics—one of the farms implemented no-tillage practices in 2013, while the second farm is under conventional soil management with moldboard plowing. Two soil types were evaluated under each farming practice: (1) a free-draining porous limestone, and (2) a lime-rich loamy soil with high silt and clay content. Field monitoring was undertaken over a two-year period and included nutrient analysis of surface and subsurface soil samples, bulk density, soil moisture, infiltration capacity, surface runoff, and analysis of phosphorus (P) and suspended solids in watercourses in close proximity to the test fields. The conversion to no-tillage changed the soil structure, leading to a higher bulk density and soil organic matter content and thereby increasing the soil moisture levels. These changes impacted the denitrification rates, reducing the soil nitrate (NO3) levels. The increased plant material cover under no-tillage increased the levels of soil phosphate (PO43–) and PO43– leaching. The extent to which soil functions were altered by farming practice was influenced by the soil type, with the free-draining porous limestone providing greater benefits under no-tillage in this study. The importance of including soils of different characteristics, texture, and mineralogy in the assessment and monitoring of farming practice is emphasized, and additionally the between field and in-field spatial variability (both across the field and with depth) highlighted the importance of a robust sampling strategy that encompasses a large enough sample to effectively reveal the impact of the farming practice.

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Abstract

Soil improvement measures need to be ecologically credible, socially acceptable and economically affordable if they are to enter widespread use. However, in real world decision contexts not all measures can sufficiently meet these criteria. As such, developing, selecting and using appropriate tools to support more systematic appraisal of soil improvement measures in different decision-making contexts represents an important challenge. Tools differ in their aims, ranging from those focused on appraising issues of cost-effectiveness, wider ecosystem services impacts and adoption barriers/opportunities, to those seeking to foster participatory engagement and social learning. Despite the growing complexity of the decision-support tool landscape, comprehensive guidance for selecting tools that are best suited to appraise soil improvement measures, as well as those well-adapted to enable participatory deployment, has generally been lacking. We address this gap using the experience and survey data from an EU-funded project (RECARE: Preventing and REmediating degradation of soils in Europe through land CARE). RECARE applied different socio-cultural, biophysical and monetary appraisal tools to assess the costs, benefits and adoption of soil improvement measures across Europe. We focused on these appraisal tools and evaluated their performance against three broad attributes that gauge their differences and suitability for widespread deployment to aid stakeholder decision making in soil management. Data were collected using an online questionnaire administered to RECARE researchers. Although some tools worked better than others across case studies, the information collated was used to provide guiding strategies for choosing appropriate tools, considering resources and data availability, characterisation of uncertainty, and the purpose for which a specific soil improvement measure is being developed or promoted. This paper provides insights to others working in practical soil improvement contexts as to why getting the tools right matters. It demonstrates how use of the right tools can add value to decision-making in ameliorating soil threats, supporting the sustainable management of the services that our soil ecosystems provide.

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Abstract

This paper draws on network science and uses a Social Network Analysis to improve our understanding of how the implementation of no-till in England is influenced by farmers' social networks. No-till is a low disturbance farming practice with potential to benefit soil health, the aquatic environment and farm economy, but is currently only implemented at a small scale in Europe. Interpersonal networks are important for farmers and influence farmer learning and decision-making and farmers often view each other as their main source of information. In this study, the social networks of 16 no-till farmers in England were mapped and semi-structured interviews carried out to assess the link between farmer network characteristics and the implementation of no-till in England. We also aimed to improve our understanding of the nature and extent of knowledge exchanged within farmer networks and their spatial and temporal dynamics. Our findings suggest that intermediary farmers had an important role in increasing the information flow and knowledge exchange between the different clusters of the no-till farmer network. These intermediaries were also the biggest influencers as they were often no-till farmers with a high level of experiential knowledge and viewed as important sources of information by other farmers. No-till farmer networks were geographically distributed as the farmers preferred to discuss farming practices with similar minded no-till farmers rather than local conventional farmers who did not understand what they were trying to achieve. Therefore, online communication platforms like social media were important for communication. We question the role of formal extension services in supporting farmers with innovative practices like no-till and suggest that advisors should strive to improve their understanding of these well-developed information networks to enable a more streamlined and efficient information diffusion.

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Abstract

This review provides a comprehensive evaluation of no-till (NT) based on recent studies (post-2000) in NW Europe and evaluates the separate effect of the NT and other associated practices (e.g. cover crops, crop residue and crop rotations) individually and collectively on the water purification and retention functions of the soil. It also assesses the applicability of NT compared to conventional tillage (CT) systems with reference to a number of soil physical characteristics and processes known to have an important influence on water purification and retention functions. The literature search was carried out by a systematic approach where NT practices were assessed against soil structure, erosion, nutrient leaching/loss, water retention, infiltration and hydraulic conductivity (combinations of criteria = 40). Articles were selected based on their relevance in relation to the topic and location within NW Europe (n = 174). Results show that NT has large potential as an erosion mitigation measure in NW Europe with significant reductions of soil losses from agricultural fields, providing potential beneficial effects regarding inputs of sediment and particulate phosphorous (P) to water bodies. However, NT increased losses of dissolved reactive phosphorus (DRP) and had little effect on nitrogen (N) leaching, limiting the overall positive effects on water purification. Soil structural properties were often found to be poorer under NT than CT soils, resulting in decreased water infiltration rates and lower hydraulic conductivity. This was an effect of increased topsoil compaction, reduced porosity and high bulk density under NT, caused by the absence of topsoil inversion that breaks up compacted topsoil pans and enhances porosity under CT. However, several studies showed that soil structure under NT could be improved considerably by introducing cover crops, but root and canopy characteristics of the cover crop are crucial to the achieve the desired effect (e.g. thick rooted cover crops beneficial to soil structural remediation can cause negative effects in soils sensitive to erosion) and should be considered carefully before implementation. The contribution of NT practices to achieve Water Framework Directive (WFD) objectives in NW Europe is still uncertain, in particular in regards to water retention and flood mitigation, and more research is required on the total upscaled effects of NT practices on catchment or farm scale.

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Abstract

Encouraging the uptake of sustainable soil management practices often requires on‐farm experiential learning and adaptation over a sustained period, rather than the traditional knowledge transfer processes of identifying a problem and implementing a solution. Farmer‐to‐farmer learning networks are emerging with farmers experimenting and sharing knowledge about these practices amongst themselves. One potential communication channel for such interaction and knowledge sharing is social media and Twitter in particular. A content analysis of a Twitter account for an EU research project, SoilCare, and in‐depth qualitative interviews with five farmers using Twitter were used to illustrate the extent and type of farmer‐to‐farmer knowledge sharing in relation to sustainable soil management practices. Evidence of farmer learning and knowledge sharing on Twitter with respect to these practices was identified. Twitter can capture the immediacy of the field operations and visual impacts in the field. Furthermore, the brief messages channeled through Twitter appeal to time‐constrained farmers. The ability for interaction around a particular hashtags in Twitter is developing virtual networks of practice in relation to sustainable soil management and within these networks farmer champions are emerging that are respected by other farmers. Twitter works best for those actively seeking information, rather than passive recipients of new knowledge. Therefore, its use with other forms of face‐to‐face interaction as part of a blended learning approach is recommended. Twitter also offers a potential space for other actors, such as researchers and advisers, to interact and share knowledge with farmers. This article is protected by copyright. All rights reserved.

Abstract

The hydrological processes associated with vegetation and their effect on slope stability are complex and so difficult to quantify, especially because of their transient effects (e.g. changes throughout the vegetation life cycle). Additionally, there is very limited amount of field based research focusing on investigation of coupled hydrological and mechanical influence of vegetation on stream bank behavior, accounting for both seasonal time scale and different vegetation types, and none dedicated to marine clay soils (typically soil type for Norway). In order to fill this gap we established hydrological and mechanical monitoring of selected test plots within a stream bank, covered with different types of vegetation, typical for Norwegian agricultural areas (grass, shrubs and trees). The soil moisture, groundwater level and stream water level were continuously monitored. Additionally, soil porosity and shear strength were measured regularly. Observed hydrological trends and differences between three plots (grass, tree and shrub) were analysed and formed the input base for stream bank stability modeling. We did not find particular differences between the grass and shrub plot but we did observe a significantly lower soil moisture content, lower soil porosity and higher shear strength within the tree plot. All three plots were stable during the monitoring period, however modeling scenarios made it possible to analyse potential differences in stream bank stability under different vegetation cover depending on root reinforcement and slope angle.