Grassland-based products: quality and authentication (2024)

Mulberry (Morus spp.) as a fodder source to overcome climate change

Agroforestry practices are excellent tools to mitigate and adapt to climate change. Climate change will increase the summer drought period in the south of Europe. Feed shortage can be overcome by the use of tree leaves and soft branches to feed to livestock. The leaves of mulberry are known to be of high quality (protein content and digestibility) for animals. This experiment aims to determine productivity and fodder quality of four Morus spp. clones: M. alba criolla; M. alba tigrenda, M. alba illaverde and M. nigra. A randomized block design (3 blocks × clone) was set up in the northwest Spain (Lugo, Galicia) in 2015. One year after establishment, field measurements were recorded (survival, tree height, base and crown diameters) and plant subsamples were taken to determine production and protein content. The four Morus spp. clones showed a high survival rate (>90%). M. alba illaverde produced the highest yields and growth compared with other mulberry clones. Despite differences in production, all four Morus spp. clones have shown high leaf protein content (100-180 g kg‑1) with no significant differences among them. Thus, our initial study showed promising results on the use of mulberry leaves as animal fodder in temperate agroforestry systems.

Maize yield in silvoarable systems established under Prunus avium L. in Galicia (NW Spain)

In recent years, in Galicia (NW Spain) the forest area has increased gradually and therefore the availability of agricultural area has decreased. This factor could favour the establishment of silvoarable systems in this region with crops such as maize, because in Galicia maize is the main forage crop to overcome periods of shortage in summer and winter. In silvoarable systems, the production of the crops depends, among other aspects, on tree species and its density when planted. The aim of this study, in Galicia (NW Spain), was to evaluate the yield of maize at different distances from the trees (1.5, 3 and 6 m) in a silvoarable system under Prunus avium L., compared with an exclusively agronomic system. The results obtained showed that maize production increased significantly with the distance from the trees and that maize production combined with trees was lower than the production found in the plots without trees, because of a reduction in maize yield and also due to the surface occupied by trees.

Productivity of silvopastoral systems under Pinus radiata D. Don estimated with the Yield-SAFE model

The Yield-SAFE is a biophysical model to predict the long-term production according to light and water availability in exclusively agricultural and forest systems and also in agroforestry systems. The productivity estimated with the Yield-SAFE model can be used to determine the Land Equivalent Ratio (LER). The LER allows comparison of the productivity of an agroforestry system with the productivity of a monoculture system. The objective of this study was to determine the productivity of exclusively forest and agricultural systems and a silvopastoral system established with Pinus radiata D. Don in Galicia (NW Spain) through the Yield-SAFE model to calculate the LER. The results showed that the LER simulated by the Yield-SAFE model was 1.41. This value indicates that the hypothetical silvopastoral system of this experiment produced 41% more than the exclusively forest and agricultural systems, probably due to the diversified production of the silvopastoral systems. Therefore the establishment of silvopastoral systems could be promoted in Europe due to its high productivity compared with the exclusively forest and agricultural systems, which is increased by the non-market products that agroforestry systems support.

Agroforestry systems: an option for mitigation and adaptation to overcome global climate change

Agroforestry, a combination of a woody (shrub/tree) with an herbaceous component (crops/pasture) is considered an important tool to mitigate and adapt agrarian systems to global climate change. This fact is based on the capacity that AGF systems have to preserve C already accumulated in the woody component but also to increase C sequestration in a tree-less system when trees are planted. Nitrate and CO2 emissions can be reduced by the consumption of the biomass of the understory in forests with high fire risk, but also for the better use of fertilizers in more open systems that will contribute to mitigate the negative effects of this fertiliser inputs on GHG atmosphere release. Resilience is also improved as biodiversity in AGF systems is usually higher than in tree-less systems.

The yield and variation of chemical composition of cocksfoot biomass after five years of digestate application

Biogas production is the optimal way to utilize organic materials or energy crops and produce bioenergy. In many countries the number of biogas plants is increasing. The growth of biogas production directly influences the generation of digestate. An experiment on cocksfoot (Dactylis glomerata L.) fertilized with mineral fertilizer and digestate was conducted to evaluate the yield and chemical composition of cocksfoot biomass after five years of digestate application. The average results of the experiment suggest that within five years of sward use higher rates of nitrogen present in the digestate increased the biomass yield. The swards fertilized with mineral fertilizer N360 produced the same biomass yield as those fertilized with N180. The chemical and structural biomass components varied due to the influence of type and rate of fertilizers.

Tree and pasture productivity in Pseudotsuga menziesii (Mirb.) Franco silvopastoral systems fertilized with sewage sludge

In Galician silvopastoral systems (northwest Spain) fertilization with sewage sludge could enhance tree and pasture productivity which is limited by soil acidity. The effect of sewage sludge on tree growth and the pasture production is different depending on the process used to stabilize the sewage sludge. The aim of the present study was to evaluate the effect of fertilization with municipal sewage sludge, which has been stabilized using anaerobic digestion, composting, and pelletization, on tree and pasture productivity compared to control treatments (mineral and no fertilization) in a silvopastoral system under Pseudotsuga menziesii (Mirb.) Franco. Mineral fertilization increased the annual pasture production and reduced the tree heights due to the competition by the nutrients generated between pasture and trees. However, tree height was increased by the application of pelletized sewage sludge applied in split doses.

Synergies between mitigation and adaptation to climate change in grassland-based farming systems

Climate change mitigation and adaptation have generally been considered in separate settings for both scientific and policy viewpoints. Recently, it has been stressed (e.g. by the latest IPCC reports) the importance to consider both mitigation and adaptation from land management together. To date, although there is already large amount of studies considering climate mitigation and adaptation in relation to grassland-based systems, there are no studies that analyse the potential synergies and tradeoffs for the main climate change mitigation and adaptation measures within the current European Policy context. This paper reviews which mitigation and adaptation measures interact with each other and how, and it explores the potential limitations and strengths of the different policy instruments that may have an effect in European grassland-based livestock systems.

Sewage sludge fertilization effects on Q. rubra and pasture production and flora biodiversity

Fertilization is usually applied to increase land productivity, but this technique also affects biodiversity in silvopastoral systems. This study aims at evaluating the effect of different doses of sewage sludge on tree growth, pasture production and biodiversity during three years, at eight years after establishment of a silvopastoral system with Quercus rubra. Improving soil fertility increases grassland biodiversity until tree canopy cover is not complete.

Grassland term definitions and classifications adapted to the diversity of European grassland-based systems

Grasslands are represented in an unsatisfactory manner in agricultural statistics. The official definition of grasslands does not include vast areas of grazed shrubby and wooded ecosystems. Temporary grasslands are recorded as ‘Leguminous plants’ and ‘Temporary grass’ which induces doubt on the classification of grass-legume mixtures and often leads to the underestimation of temporary grassland areas. Some terms like ‘meadows’ and ‘pastures’ are often used in an imprecise and misleading way. The term ‘rough grazing’ does not include all types of natural and semi-natural grasslands, especially all types of rangelands, forest pastures and traditional hay meadows. It can thus not represent all species-rich grassland types. Improvements of the current situation are proposed. They consist mainly in: (i) better definitions of grassland terms including for pastures and meadows, permanent, agriculturallyimproved, semi-natural and natural grasslands; (ii) the classification of temporary grasslands in three categories: pure legume sowings, pure grass sowings and grass-legume mixtures; (iii) the classification of permanent grasslands in three categories: agriculturally-improved, natural and semi-natural, no longer used for production; and (iv) the introduction of a new category for grazed fallow land. The paper presents a comprehensive classification of fodder and grassland types in the agricultural area and a multilingual vocabulary.

Silvopasture: a combination of grasslands and trees to green livestock production

Nowadays, livestock production is strongly dependent on inputs produced from outside the farm, such as fertilizers and concentrates. The combination of low-density trees and grasslands allows the feeding of animals in a cheap way, as tree branches can be used as fodder during periods of forage shortage. Moreover, increased productivity is ensured, as the land-equivalent ratio of 1 ha of silvopasture is between 1.2 and 1.6 ha of forest and crop monocrops, to produce the same amount of products. The presence of trees in grasslands at low density will promote biodiversity, carbon sequestration and nutrient recycling; therefore, a promotion of efficiency in the use of the resources is definitively enhanced. This paper reviews results from a series of experiments to show how silvopasture could promote production and environmental services to provide more sustainable land use options in livestock production.