How does drought stress influence the decomposition of plant litter with contrasting quality in a grassland ecosystem?

Abstract

Background and aims Plant litter quality and water availability both control decomposition. The interaction of both parameters was never studied. We used a grassland site, where litter of contrasting quality, i.e. green litter (fresh leaves; high quality) and brown litter (dead leaves, which underwent senescence but which are still attached to the plant; low quality), is returned to soil. Green and brown litter were exposed in the field under regular weather and drought conditions. The objective of this study was to evaluate the effect of drought on the decomposition of both litter types. Methods We incubated green and brown litter of three different grassland species (Lolium perenne, Festuca arundinacea and Dactylis glomerata) alone or as litter mixture (1/3 of each of the three grassland species) in litterbags for 28 weeks. Drought conditions were simulated by rainfall exclusion. After incubation, litter residues were analysed for C and nitrogen (N) content and stable isotope composition. Additionally, we determined the response of the lignin and carbohydrate signatures to the contrasting conditions. Results C decomposition kinetics of green and brown litter under drought conditions could be explained by two pools of contrasting turnover times. Drought decreased leaf litter C and N decomposition by more than 50% compared to regular weather conditions, mainly by strongly decreasing the decomposition rate constants. The lowest C decomposition occurred for mixtures of litter from all three grassland species. Brown litter showed on average 15% higher reduction in carbon decomposition than green litter following drought. Lignin content remained similar for green and brown litter after drought and regular weather conditions, while sugar content remained similar in green litter and decreased by 18% for brown litter under drought conditions. Conclusions Our results showed different response of decomposition of litter with contrasting quality to drought. Low quality brown litter is likely to be more affected than high quality green litter. Thus, litter quality must be taken into account, when assessing the effect of drought on decomposition.

Effect of drought and salinity stresses on mineral and total protein contents of Moringa

“…In current study, this was the most probable reason of systematic decline in percentage of P with increasing periods of drought. Besides Liebersbach et al (2004) reported that salinity reduces the availability of P to by reducing the diffusion and mass flow from the soil (Schimel et al, 2007;Sanaullah et al, 2012;Lambers et al, 2008;He and Diskstra, 2014).These statements logically justify the outcomes of current study. Apart from this, Feis also considered as an important micronutrient playing important role in agriculture.…”

The Role of Plants in the Effects of Global Change on Nutrient Availability and Stoichiometry in the Plant-Soil System

“…The most common effect of drought is a decrease in soil biological activity, including decreases in soil enzyme activity (Lorenz et al, 2001;Yavitt et al, 2004;Henry et al, 2005;Peñuelas, 2005, 2010;Sardans et al, 2006Sardans et al, , 2008aSardans et al, , 2008d, mineralization (Fig. 1), and SOM decomposition (Van Meeteren et al, 2008;Sanaullah et al, 2012) that frequently decrease the availability of soil nutrients (Fig. 1).…”

Net carbon storage measured in a mowed and grazed temperate sown grassland shows potential for carbon sequestration under grazed system

“…The mean annual temperature and precipitation for the period 2006-2010 was 11.2°C and 773 mm, respectively. Details of the experimental site can be found elsewhere [23][24][25][26][27][28][29].…”