Stakeholder perspectives to prevent soil organic matter decline in Northeastern Italy

A transition from conventional to more sustainable soil management measures (SMMs) is required to reverse the current soil organic matter (SOM) losses in the agroecosystems. Despite the innovations and technologies that are available to prevent SOM decline, top–down knowledge transfer schemes that incentivize a certain measure are often ineffective. Here, we discuss relevant outcomes from a participatory approach where researchers, farmers, practitioners and government officials have discussed opportunities and barriers around SMM application to prevent SOM decline. Within a series of workshops, stakeholders identified, scored, and selected SMMs to fieldtests and evaluated the benefits and drawbacks from their application. Results showed that the stakeholders recognized the need for innovations, although they valued the most promising SMM as already available continuous soil cover and conservation agriculture. In contrast, more innovative SMMs, such as biochar use and the variable rate application of organic amendments through precision farming, were the least valued, suggesting that people’s resistance to new technologies is often governed by the socio-cultural perception of them that goes beyond the economic and technological aspects. The valuation of benefits and drawbacks by stakeholders on trialed measures emphasized that stakeholders’ perspective about soil management is a combination of economic, environmental, and socio-cultural aspects, thus corroborating the need for transdisciplinary bottom–up approaches to prevent SOM depletion and increase soil rehabilitation and SOM content

Assessing impacts of soil management measures on ecosystem services

Only a few studies have quantified and measured ecosystem services (ES) specifically related to soil. To address this gap, we have developed and applied a methodology to assess changes in ecosystem services, based on measured or estimated soil property changes that were stimulated by soil management measures (e.g., mulching, terracing, no-till). We applied the ES assessment methodology in 16 case study sites across Europe representing a high diversity of soil threats and land use systems. Various prevention and remediation measures were trialled, and the changes in manageable soil and other natural capital properties were measured and quantified. An Excel tool facilitated data collection, calculation of changes in ecosystem services, and visualization of measured short-term changes and estimated long-term changes at plot level and for the wider area. With this methodology, we were able to successfully collect and compare data on the impact of land management on 15 different ecosystem services from 26 different measures. Overall, the results are positive in terms of the impacts of the trialled measures on ecosystem services, with 18 out of 26 measures having no decrease in any service at the plot level. Although methodological challenges remain, the ES assessment was shown to be a comprehensive evaluation of the impacts of the trialled measures, and also served as an input to a stakeholder valuation of ecosystem services at local and sub-national level

Sustainable land management practices in the low-lying Venetian plain: relationship to soil ecosystem services

Sustainable land management (SLM) practices, as conservation agriculture (CA) and conventional tillage with cover crops (CC), aimed at balancing competitive agricultural production and environmental protection, have been encouraged throughout the EU through policy and subsidisation. Adoption of SLM practices that regulate biogeochemical cycles, however, requires further study, especially given the effects of local pedo-climatic variability and because middle and long-term effects are not fully understood and may differ from short-term outcomes. For these reasons, in this work, field experiments were conducted in three farms in the low-lying venetian plain, characterized by loamy soils, where CA and CC were compared to conventional intensive tillage system (CV) on trials established since 2010. The first objective of the thesis was to evaluate, by integrating experimental field results with model predictions, the potential ecosystem services provided by CA and CC practices on SOC dynamic, air quality and climate regulation, nutrition biomass and regulating of water conditions. In this experiment, CA and CC results contrasted according to the soil functions, the ecosystem service category and evaluation time span. The former was more effective in providing regulating services in the short term, and less consistent in the long term, at least for GHG mitigation. GHG control is only one of the numerous ecosystem services provided by conservation practices (e.g. reduction of erosion and P particulate loss). Many of these depend on the C content which are strongly affected by the C stratification processes. Cover crop adoption, on the contrary, showed promise in the long term, whereas short-term outcomes (two-year experiment) were negatively affected by poor cover crop growth. The second objective aimed to assess the SOC stock variation due to the adoption of CA and CC in comparison to CV within a large sample (i.e., 240) of 0-50-cm soil profiles, comparing two expansive soil sampling operations conducted in 2011 and 2017. The study showed that CA enhances SOC stratification rather than SOC accumulation, with high topsoil SOC that may have partly counteracted soil surface compaction. However, a comparison with previous SOC stock quantifications between CA and CV after three years of the experiment suggests that some SOC stock increase occurred, even at 50 cm, despite being not significant. The burial of fresh biomass-C with cover crops in arable systems (CC) enhanced SOC stock depletion most likely due to priming effects, suggesting that C input management is pivotal for its accumulation in agroecosystems with low soil fertility and low SOC protection capacity

Sustainable land management practices in the low-lying Venetian plain: relationship to soil ecosystem services

Sustainable land management (SLM) practices, as conservation agriculture (CA) and conventional tillage with cover crops (CC), aimed at balancing competitive agricultural production and environmental protection, have been encouraged throughout the EU through policy and subsidisation. Adoption of SLM practices that regulate biogeochemical cycles, however, requires further study, especially given the effects of local pedo-climatic variability and because middle and long-term effects are not fully understood and may differ from short-term outcomes. For these reasons, in this work, field experiments were conducted in three farms in the low-lying venetian plain, characterized by loamy soils, where CA and CC were compared to conventional intensive tillage system (CV) on trials established since 2010. The first objective of the thesis was to evaluate, by integrating experimental field results with model predictions, the potential ecosystem services provided by CA and CC practices on SOC dynamic, air quality and climate regulation, nutrition biomass and regulating of water conditions. In this experiment, CA and CC results contrasted according to the soil functions, the ecosystem service category and evaluation time span. The former was more effective in providing regulating services in the short term, and less consistent in the long term, at least for GHG mitigation. GHG control is only one of the numerous ecosystem services provided by conservation practices (e.g. reduction of erosion and P particulate loss). Many of these depend on the C content which are strongly affected by the C stratification processes. Cover crop adoption, on the contrary, showed promise in the long term, whereas short-term outcomes (two-year experiment) were negatively affected by poor cover crop growth. The second objective aimed to assess the SOC stock variation due to the adoption of CA and CC in comparison to CV within a large sample (i.e., 240) of 0-50-cm soil profiles, comparing two expansive soil sampling operations conducted in 2011 and 2017. The study showed that CA enhances SOC stratification rather than SOC accumulation, with high topsoil SOC that may have partly counteracted soil surface compaction. However, a comparison with previous SOC stock quantifications between CA and CV after three years of the experiment suggests that some SOC stock increase occurred, even at 50 cm, despite being not significant. The burial of fresh biomass-C with cover crops in arable systems (CC) enhanced SOC stock depletion most likely due to priming effects, suggesting that C input management is pivotal for its accumulation in agroecosystems with low soil fertility and low SOC protection capacity