Biomass Allocation and Leaf Morphology of Saplings Grown under Various Conditions of Light Availability and Competition Types

Abstract

Plant growth is almost always limited by light availability and competition. However, plants are generally plastic and can change their morphology and biomass allocation to optimize growth under suboptimal conditions. We set up a controlled pot experiment with three light availability levels (10%, 20%, and 50%) to study the effect of light and competition on the biomass allocation and leaf morphology in monospecific and mixed pots of recently planted European beech (Fagus sylvatica L.), Norway spruce (Picea abies (L.) Karst.), and Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) saplings using a quantile regression model. Specific leaf area (SLA) showed the strongest reaction and increased with decreasing light availability. Woody aboveground mass fraction (AMF) increased with decreasing light availability, but the effect of light on biomass allocation was less pronounced than on SLA. The SLA, woody AMF, and root mass fraction (RMF) of the two conifer species and European beech varied greatly, with European beech having a higher SLA and RMF than the two conifer species. The associated effect of plant size on biomass allocation was small, and the strength of the association was not meaningful on a practical level. The competitor’s effect on biomass allocation was minor overall and only present for some species, suggesting that species’ functional dissimilarity does not greatly affect allocational patterns in early tree development stages.

Kin and Non-Kin Connected Plants Benefit More Than Disconnected Kin and Non-Kin Plants under Nutrient-Competitive Environments

“…Biomass allocation to organs is a key component of plant life history and plays an important role in the trade-off between resource acquisition and resource utilization [ 37 , 38 , 39 ]. Plants can exhibit plasticity and adjust the distribution of their organs and systems to meet available resources [ 39 ]. Nutrient availability is one of the important factors driving changes in biomass allocation [ 38 ].…”

“…Taken together with the results in LAR and SLA, the patterns suggest that non-kin compete more aboveground than belowground. Increased allocation to leaf or stem can indicate increased competition for light [ 39 , 40 ], but it may also indicate increased performance, such that greater allocation to stem could lay the foundation for increased seed crop [ 41 ]. Given that quinoa grows in dry environments at high elevations, where water and nutrient stress may be more important selective constraints than light, it seems unlikely that quinoa would possess phenotypic plasticity to respond to light competition [ 42 , 43 ], but would possess root plasticity to respond to water and nutrient supply [ 44 ].…”

“…Plants can adapt to different light and nutrient supply conditions, presumably to overcome resource limitations [ 45 , 46 ]. An important variable in their adaptation is the ratio of leaf area to root length, which is based on the allocation of plant biomass and organ morphology [ 39 , 45 , 47 ]. Specific Leaf Area (SLA) and Leaf Area Ratio (LAR) are important leaf characteristics because they represent the ratio of the leaf’s light-receiving surface per unit dry weight investment [ 45 , 48 ].…”

A response of biomass and nutrient allocation to the combined effects of soil nutrient, arbuscular mycorrhizal, and root-knot nematode in cherry tomato

“…In general, the root-shoot ratio (root biomass to aboveground biomass) and reproductive allocation (reproductive organ biomass to total biomass) can be used to determine the resource allocation strategies of plants for vegetative growth and reproduction, which are also key parameters reflecting plant survival strategies (Liu and Li, 2020;Li et al, 2021;Zhou et al, 2021). The resource allocation strategies of plants may change with resource supply changes in environment, which will lead to changes in root-shoot ratio and reproductive investment for plants to adapt to variable conditions (Zhang et al, 2021;Bebre et al, 2022;Meng et al, 2022;Zhou et al, 2022). Therefore, as one of the adaptation strategies to environmental factors, the resource allocation strategy of plants is usually plastic (Xie et al, 2012).…”