Boron application increases growth of Brazilian Cerrado grasses

Abstract

Nutrients are known to limit productivity of plant communities around the world. In the Brazilian Cerrado, indirect evidences point to phosphorus as the main limiting nutrient, but some fertilization experiments suggest that one or more micronutrients might play this role. Boron is one of the essential micronutrients for plants. Agronomically, it received some attention, but it has mostly been neglected in ecological studies assessing the effects of nutrients on plant growth. Through field fertilization and mesocosm experiments in a degraded area in the Cerrado, we show that boron addition increased biomass production of herbaceous vegetation. This could be related to a lower aluminum uptake in the boron fertilized plants. Even considering that plant growth was promoted by boron addition due to aluminum toxicity alleviation, this is the first study reporting boron limitation in natural, noncultivated plant communities and also the first report of this kind in vegetative grasses. These results contribute to disentangling patterns of nutrient limitation among plant species of the species‐rich, aluminum‐rich, and nutrient‐poor Cerrado biome and highlight the potential role of micronutrients, such as boron, for growth of noncrop plants. Understanding how nutrient limitation differs among functional groups in the highly biodiverse areas founded on ancient tropical soils may help managing these plant communities in a changing world.

Soil properties as key predictors of global grassland production: Have we overlooked micronutrients?

“…The potentially important contributing role of micronutrients for grassland productivity has been highlighted in fertilisation experiments (Fay et al, 2015; Lannes et al, 2016), but few studies in non‐agricultural grasslands focused on micronutrients additions specifically (however, see Lannes et al (2020) for the role of B as limiting factor in Cerrado grasslands). Therefore, the role of micronutrient deficiency in the productivity of non‐agricultural grasslands globally has not been explicitly considered.…”

“…Climate, atmospheric N deposition and soil physicochemical properties determining soil fertility (SOM, CEC, pH) were expected to be the main overarching drivers of global grassland biomass production (Bünemann et al, 2018; Huxman et al, 2004; Sala et al, 1988; Stevens et al, 2015) and their influence was therefore tested first (Figure 2c). In addition, we hypothesised that the availability of the most limiting macronutrients (NP) and/or other nutrients explain additional variation due to their important role in (co)‐limiting grassland productivity (Elser et al, 2007; Fay et al, 2015; Harpole et al, 2011; Lannes et al, 2020; Olde Venterink et al, 2001). Besides direct effects, we tested all possible indirect effects of climate on aboveground biomass through soil physicochemical properties (Zhao et al, 2019) and soil nutrients (Bünemann et al, 2018; Havlin, 2004) (Figure 2b).…”

The effects of tree cover and soil nutrient addition on native herbaceous richness in a neotropical savanna

“…In contrast to experiments that show that diverse ecosystems tend to be more productive and stable (Spehn et al 2005; Tilman et al, 2001), there is often a decline in diversity when productivity is manipulated by adding resources (Bobbink et al, 2010; DiTommaso & Aarssen, 1989). In savannas of central Brazil, under nitrogen and phosphorus addition, density, richness and diversity of the shrub‐tree layer and biomass of native C 3 grasses were reduced (Bustamante et al, 2012; Jacobson, Bustamante & Kozovits, 2011), while nitrogen and phosphorus, combined with other nutrients, increased the biomass of alien and growth of native C 4 grasses (Lannes et al, 2016) and boron addition increased biomass production of savanna herbaceous vegetation (Lannes et al, 2020).…”

Potential of Acid Phosphatase Activity and Mycorrhizal Colonization to Reduce Phosphorus Fertilization in Maize Cultivated in Brazil

“…Extractable Al was measured after extraction with 1 M KCl and titration with NaOH using the phenolphthalein method. All soil chemical characteristics were determined through standard methods at the UNESP Soil Laboratory according toRaij et al (2001) andLannes et al (2020b). At the end of the experiment, one soil sample per pot was collected for determinations of nutrients following the same methods.…”