Carbon allocation dynamics one decade after afforestation with Pinus radiata D. Don and Betula alba L. under two stand densities in NW Spain

Silvopastoral systems can contribute to the mitigation of climate change by functioning as sinks for greenhouse gases better than exclusively agricultural systems. Tree species, density, and an adequate management of the pasture carrying capacity contribute to the capacity of carbon sequestration. In this study, the capacities for carbon sequestration in silvopastoral systems that were established with two different forest species (Pinus radiata D. Don and Betula alba L.) and at two distinct densities (833 and 2500 trees ha−1) were evaluated. Tree, litterfall, pasture and soil carbon storage determinations were carried out to deliver carbon sequestration in the different pools within the first 11 years of a plantation establishment. The results show that the global capacity for carbon sequestration in silvopastoral systems with pine canopy was higher than with birch cover. Independently of the forest species, the capacity for carbon sequestration increased when the systems were established at higher plantation densities. There were found strong differences in the relative proportions of carbon in each component of the system (litterfall, tree, pasture and soil). The soil component was found to be most important in the case of the broadleaf forest established at low density. The establishment of a silvopastoral system enhanced soil carbon storage, since afforestation was carried out, which results in a more enduring storage capacity compared with treeless areas.Spanish Ministry and Xunta de Galici

Supportive Business Environments to Develop Grass Bioeconomy in Europe

Grasslands cover almost half of the total European agricultural area and are the source of a wide range of public goods and services. Yet, their potential to produce innovative bio-based products, such as paper and plastic, remains widely untapped. We employ a multiple case study approach and implement the Business Environment Framework by Adamseged and Grundmann (2020) on eighteen alternative grass-based businesses to investigate the interdependencies between these successful business models and their business environments. The subsequent analysis reveals that the deployment of funds and policies to support alternative grass-based products remains low in most regions of Europe. Our findings highlight that aligned funding mechanisms that incorporate and promote the specific benefits generated by grass-producing and grass-processing businesses are key to overcoming the barriers related to the competition of bio-based products with the established fossil-fuels-based economic system. To make alternative grass-based markets more dynamic, increasing consumer awareness through adequate marketing is perceived as an important aspect. Capacity building and alignment efforts need to be strengthened and coordinated at local and higher levels to enable the replication and scale-up of novel grass-based businesses in Europe and beyond

Zinc and copper availability in herbage and soil of a Pinus radiata silvopastoral system in Northwest Spain after sewage-sludge and lime application

Silvopastoral systems are ancient farming systems in the world, consisting of the combination of a woody component (trees or shrubs) and crops and/or animals within the same land-management unit. In various European Union (EU) countries, the possibility of using sewage sludge as a fertilizer is under consideration as a viable method of disposal, considering the increase in sewage-sludge production in recent years and the restrictions imposed by European policy on the usual methods of disposal. The concern is the concentration of heavy metals, which can reach humans through the food chain. In Spain, R.D. 1310/1990, as well as European Directive 86/278, limit the total in-soil heavy-metal concentration, but not the solubility changes, which directly affect plant absorption and leaching of heavy metals throughout the soil profile. The objective of this experiment was to compare, in a silvopastoral system over a period of 3 years, the effect of applying three doses of sewage sludge combined with and without liming, on total and available soil Zn and Cu and their concentration in plants. Liming did not affectct Zn and Cu availability; however, sewage sludge increased Zn and Cu availability, though total in-soil Zn was increased only in November 2000. In-plant Zn concentration was increased by sewage sludge in the last 2 years of the study. In all cases, the quality of forage obtained and measured with regard to the concentrations of Zn and Cu was adequate for animal consumption. With respect to sewage-sludge application as a fertilizer, the management of heavy-metal availability must be included in the policy, because environmental risk could then be adequately evaluated

Soil Carbon in Agroforestry Systems: An Unexplored Treasure?

Soil organic matter (SOM), which contains more reactive organic carbon (C) than any other single terrestrial pool, plays a major role in determining C storage in ecosystems and regulating atmospheric concentrations of carbon dioxide (CO2)^1^. Agroforestry, the practice of growing trees and crops in interacting combinations on the same unit of land^2^, primarily by resource-poor smallholder farmers in developing countries, is recognized as a strategy for soil carbon sequestration (SCS) under the Clean Development Mechanism (CDM) of the Kyoto Protocol^3^. The understanding about C storage and dynamics under agroforestry systems (AFS), however, is minimal. Our studies under various AFS in diverse ecological conditions in five countries showed that tree-based agricultural systems, compared to treeless systems, stored more C in deeper soil layers up to 1 m depth under comparable conditions. More C is stored in soil near the tree than away from the tree; higher SOC content is associated with higher species richness and tree density; and C3 plants (trees) contribute to more C in the silt- + clay-sized (<53 µm) fractions that constitute more stable C, than C4 plants, in deeper soil profiles4 - 8. These results provide clear indications of the possibilities for climate change mitigation through SCS in AFS, and opportunities for economic benefit - through carbon trading - to millions of smallholder farmers in developing countries

Biochar production from late-harvest grass – Challenges and potential for farm-scale implementation

[Abstract:] Grasslands play a crucial role in European agriculture and ecology, but are often underutilized due to low-value end-products. The utilisation of late-harvest grass for biochar and heat generation on farm-level is being studied as a potential negative emissions technology. Technical (energy provision and carbon sink), economic (cost vs. benefit), political (regulatory framework) and social (SWOT) perspectives are being evaluated. Technical feasibility has been demonstrated with three different farm-scale technologies and the energetic and carbon-sink potential evaluated. When a continuously operating allothermal unit is evaluated, 35 % of the input biomass energy content can be utilized for heating a farm, in combination with the potential to provide a carbon sink. The cost-benefit analysis shows important monetary savings when including the agronomic value (based on the market price) of the produced biochar. An assessment of the regulatory framework of biochar production in Germany presents a multitude of regulations applying to such technologies some of which provide a hurdle to navigate and may incur excessive costs for farmers as small-scale biochar producers. A SWOT analysis of a case in Brandenburg, Germany highlights strengths and opportunities, but also obstacles such as lack of infrastructure and regulatory support. This study highlights the need for further development of suitable technology and research on the long-term economic and carbon sink potential of biochar.This work was performed within the GO-GRASS project and has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement number 862674. We thank all the partners who collaborated with the data collection. We would also like to thank Philipp Grundmann for the coordination of the GO-GRASS project

Silvopasture policy promotion in European Mediterranean areas

Silvopasture is the deliberate integration of a woody component with grazed pastures as understorey. It is one of the most extended agroforestry practices all over the world. Silvopasture use is key to increase the sustainability of livestock farming systems as silvopasture reduces the use of concentrates since the woody component provides feed for animals. However, it is not an extensively used practice in Europe. This paper aims at evaluating, from Eurostat, LUCAS database and the 118 rural development programs, the current situation of permanent grasslands in the Mediterranean area of Europe as well as the rural development programmes fostering silvopasture to better understand how sustainable land use systems are promoted and provide insights to foster silvopasture across Europe. The results of this study show that most of the policy measures related to silvopasture are adapted to the local necessity. The already existing agroforestry managed land (dehesas/montado) are related to measures supporting regeneration and maintenance while in those areas where agroforestry does not exist the measures are related to forest fire prevention.MRML was supported by the European Commission through the AFINET (grant agreement no 727872) and the Go-Grass projects (grant agreement no 862674) from the European Union´s H2020 Research and Innovation Programme (https://ec.europa.eu/programmes/horizon2020/ en) and the Open2preserve project (SOE2/P5/E0804) from the Interreg Sudoe Programme (https://interreg-sudoe.eu/gbr/home). ARR was supported by the Xunta de Galicia, Consellerı´a de Educación, Universidade e Formación Profesional (https://www.edu.xunta.gal/portal/es) through the Consolidation funds 2019–2022. NFD was also supported by the Xunta de Galicia, Consellerı´a de Educacio´n, Universidade e Formación Profesional (https://www.edu.xunta.gal/portal/es) (Programa de axudas a´ etapa posdoutoral modalide B DOG n˚ 213, 08/11/2019 p.48018, exp: ED481D 2019/009). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.info:eu-repo/semantics/publishedVersio

Responses in soil carbon and nitrogen fractionation after prescribed burning in the Montseny biosphere reserve (NE Iberian Peninsula)

Prescribed fire is one of the most widely-used management tools to recover encroached rangelands. Fire has been reported to cause changes in the soil physical and chemical properties. However, the legacy effects of former plant species on soil responses to fire remains unknown. The legacy effect of the former extant plant species on soil carbon (C) and nitrogen (N) fraction- ation distribution after prescribed burning in topsoil (0–5 cm and 5–10 cm) was investigated in Mediterranean shrublands in Montseny. We sampled soils under five vegetation patch types: Cytisus scoparius L., Calluna vulgaris L., Erica arborea L., Pteridium aquilinum L., and Cladonia biocrusts, pre- and post-burning. Multivariate analysis on soil C and N fractions showed that soils under the legume Cytisus and the biocrust were the most differentiated. Vegetation patch types tended to respond differently to burning, soils under Cytisus, Cladonia and Calluna showing the strongest response. Total C and N, and C and N in sand decreased after burning in the 0–5 cm soil layer. Conversely, C in silt, as well as N in clay and silt, increased with soil depth after burning. This study will be helpful for understanding ecological legacy effects and their possible consequences when planning prescribed burningThis study was developed through projects OPEN2PRESERVE (SOE2/P5E0804), from the EU SUDOE; and IMAGINE (CGL2017-85490-R), from the Spanish Science Foundatio