Seasonal dynamics of biomass production and herbage quality of three grasslands with contrasting functional compositions

Abstract

Classifying grasses into plant functional types (PFT) according to their strategy of nutrient capture (PFT A, B and b) or nutrient conservation (PFT C) is claimed to predict variability in biomass production and herbage quality in grasslands. PFT A, B and b are characterized by higher production than PFT C, with higher nutritive value, which decreases rapidly. PFT C is characterized by lower nutritive value, which remains more stable in time. The aim of this study was to quantify the consequences of PFT composition at the community level on the seasonal dynamics of biomass and herbage quality for livestock feed. We studied three grasslands located in the same area with contrasting PFT composition and classified PFT A, PFT Bb and PFT C. The dynamics of vegetation stages, dry-matter yield and nutritive value were followed over three vegetation cycles in 2007-2008. In the first cycle, biomass accumulation was high for the PFT A and PFT Bb grasslands and the high quality of herbage declined rapidly with the reproductive development. By contrast, biomass accumulation was slow in the PFT C grassland, with a lower quality that declined slowly, consistent with the later reproductive development. For regrowth cycles, the same ranking of grasslands was observed for biomass accumulation, and differences in digestibility were similar to those observed at the beginning of the first vegetation cycle. Combining type of grassland with sum of temperature for the first cycle and regrowth days for the second and third vegetation cycles provided quantitative models of herbage biomass and quality.

Assessing the Effects of Grassland Management on Forage Production and Environmental Quality to Identify Paths to Ecological Intensification in Mountain Grasslands

“…Moreover, such mixtures may have positive effects on the stability and resilience of agronomic properties (Pakeman 2014), particularly when facing climatic variability and stresses (see Tracy and Sanderson 2004 for meadows;Deak et al 2009 for pastures), and secondary effects on other ecosystem functions able to support an EI process (Grigulis et al 2013). The functional diversity of grass species included in some of these mixtures may also help to provide better flexibility in the timing of use through phenological complementarity between species (Michaud et al 2011).…”

Herbage dry‐matter production and forage quality of three legumes and four non‐leguminous forbs grown in single‐species stands

“…In contrast, semi‐natural grasslands include a greater range of species, including legumes and other forbs, and, in some cases, these are of high feed value (Jeangros and Thomet, ). Yield and herbage quality of semi‐natural grasslands also vary, depending on species composition, at successive growth cycles during the growing season (Michaud et al ., ). Perceived benefits of forbs in grassland swards have been widely reported, although often based on limited evidence (Voisin, ; Foster, ; Smidt and Brimer, ).…”

Long‐term evolution and prediction of feed value for permanent mountain grassland hay: Analysis of a 32‐year data set in relation to climate change

“…(Thorvaldsson, 1987) or in combination with other agro-climatic or chemical criteria (Groot, Lantinga, Neuteboom, & Deinum, 2003;Michaud et al, 2012;Michaud, Plantureux, Pottier, & Baumont, 2015), to predict the feed value of forage. (Thorvaldsson, 1987) or in combination with other agro-climatic or chemical criteria (Groot, Lantinga, Neuteboom, & Deinum, 2003;Michaud et al, 2012;Michaud, Plantureux, Pottier, & Baumont, 2015), to predict the feed value of forage.…”

“…Making ground-dried hay requires 3 to 4 days without rain to provide favourable conditions for the cut grass to dry. In mountain areas, an earlier cutting date in spring may coincide with a higher probability of rainfall (Michaud et al, 2012). In mountain areas, an earlier cutting date in spring may coincide with a higher probability of rainfall (Michaud et al, 2012).…”

“…DEROCHE Et al. (Thorvaldsson, 1987) or in combination with other agro-climatic or chemical criteria (Groot, Lantinga, Neuteboom, & Deinum, 2003;Michaud et al, 2012;Michaud, Plantureux, Pottier, & Baumont, 2015), to predict the feed value of forage.…”