Herbaceous species and dry forest species have more acquisitive leaf traits than woody species and wet forest species

Abstract

Life forms are key to understand the changes in species composition and vegetation types in space and with succession over time. We asked how life forms from dry and wet regions differ in their leaf traits and trait hyperspace (i.e. trait variation) in early tropical forest succession on abandoned agricultural fields. We compared 324 early successional species from six life forms (herbs, grasses, vines, lianas, shrubs and trees) that occur in the first 5 years of succession on abandoned fields in Ghanaian wet and drought deciduous tropical forests. We measured 12 leaf traits that are important for carbon, water and nutrient use. A principal component analysis showed that 46% of trait variation is captured by a two‐dimensional spectrum of plant form and function: a leaf economics spectrum underpinning fast‐slow growth strategies, and a leaf size spectrum related to plant size and heat balance, which underlie species sorting along environmental gradients in space and time (during succession). Herbaceous and woody life forms had different leaf economics strategies: herbaceous species had more acquisitive trait values (e.g. higher leaf nutrient concentrations) that increase resource capture and use efficiency whereas woody species had more conservative trait values (e.g. higher leaf mass per area) that increase resource conservation. Regardless of life forms, dry forest species and deciduous species had more acquisitive trait values than wet forest species and evergreen species as they maximize their growth during the shorter growing season. The trait hyperspace was larger for woody life forms especially in wet forests. Synthesis. Herbaceous species had ‘faster’ leaf economics trait values and, hence, rapid carbon gain, explaining their success earlier in succession. In contrast, woody species had ‘slower’ resource conservation trait values that increase persistence, thus explaining their success later in succession. Deciduous species especially in a dry region had higher leaf nitrogen and phosphorus concentration to attain faster carbon gain to cope with a seasonally harsh environment. The trait hyperspace was generally smaller in the dry forest, as there are more deciduous species, and as a result, there is less variation in leaf lifespan and associated traits. Read the free Plain Language Summary for this article on the Journal blog.

Morphological responses of root hairs to changes in soil and climate depend on plant life form

“…Plant absorption of mobile nutrients is directly proportional to root hair length because soil nutrients more easily reach the roots with greater root hair lengths (Bates and Lynch, 2001;Evans, 2012). For woody plants, by contrast, we only observed that root hair length was positively related to soil K. These results indicate that morphological traits of the root hairs of herbaceous plants were more closely related (Bibikova and Gilroy, 2002;Matsuo et al, 2023). Specifically, herbaceous plants depend primarily on root proliferation for resource foraging, while woody plants depend mainly on mycorrhizal foraging (Michael, 2001;Tawaraya, 2003;Golivets et al, 2024).…”

“…On the other hand, herbaceous plants have shallower root systems compared with woody plants ( Van der Waal et al, 2009;Wang et al, 2023;Golivets et al, 2024). The vertical distribution of the root system is directly related to their efficiency in absorbing soil resources (Matsuo et al, 2023). Consequently, woody plants are subjected to more nutrient stress than herbaceous plants (Wang et al, 2020a).…”

“…Life forms are key to understanding changes in species composition and vegetation types and their functional traits (Matsuo et al, 2023). Different life forms, such as woody and herbaceous plants, vary in woodiness, longevity, size, form and physiology, leading to distinct responses to the environment changes (Grytnes and Felde, 2014;Pérez-Harguindeguy et al, 2016).…”

Phylogenetic diversity drives soil multifunctionality in arid montane forest-grassland transition zone

“…Therefore, understory plants must have a strong light capture capacity to meet their growth requirements. Therefore, during the transition, plants with smaller specific leaf area and thicker leaves are better adapted to the increased solar radiation and reduced water availability ( Matsuo et al., 2024 ) ( Supplementary Figures 1 and 2 ). Forest and grassland possess elevated functional diversity, a broad variety of species traits, and more comprehensive resource utilization in comparison to the transition zone.…”

“…The trend of FDis and RaoQ was consistent, higher in grassland than in other locations (Figures 3G, H). These findings suggest that plant species in grassland exhibit a greater degree of trait differentiation and ecological niche differentiation, leading to more efficient resource utilization and relatively weaker competition, resulting in higher productivity (Mason et al, 2005).In the transition zone, the variation in CWM.H reflects the regular spatial distribution of plants. This distribution effectively reduces runoff and maintains soil nutrients necessary for plant growth.…”