Linkages between Phosphorus and Plant Diversity in Central European Forest Ecosystems—Complementarity or Competition?

Abstract

The phosphorus nutrition status of European forests has decreased significantly in recent decades. For a deeper understanding of complementarity and competition in terms of P acquisition in temperate forests, we have analyzed α-diversity, organic layer and mineral soil P, P nutrition status, and different concepts of P use efficiency (PUE) in Fagus sylvatica L. (European beech) and Picea abies (L.) H. Karst. (Norway spruce). Using a subset of the Second National Soil Survey in Germany, we correlated available data on P in the organic layer and soil with α-diversity indices for beech and spruce forests overall and for individual vegetation layers (tree, shrub, herb, and moss layers). Moreover, we investigated α-diversity feedbacks on P nutrition status and PUE of both tree species. The overall diversity of both forest ecosystems was largely positively related to P content in the organic layer and soil, but there were differences among the vegetation layers. Diversity in the tree layer of both forest ecosystems was negatively related to the organic layer and soil P. By contrast, shrub diversity showed no correlation to P, while herb layer diversity was negatively related to P in the organic layer but positively to P in soil. A higher tree layer diversity was slightly related to increased P recycling efficiency (PPlant/Porganic layer) in European beech and P uptake efficiency (PPlant/Psoil) in Norway spruce. The diversity in the herb layer was negatively related to P recycling and uptake efficiency in European beech and slightly related to P uptake efficiency in Norway spruce. In spruce forests, overall and herb species richness led to significantly improved tree nutrition status. Our results confirm significant, non-universal relationships between P and diversity in temperate forests with variations among forest ecosystems, vegetation layers, and P in the organic layer or soil. In particular, tree species diversity may enhance complementarity and hence also P nutrition of dominant forest trees through higher PUE, whereas moss and herb layers seemed to show competitive relationships among each other in nutrient cycling.

Mycorrhizal Phosphorus Efficiencies and Microbial Competition Drive Root P Uptake

“…In mesocosms with reconstructed soil layers composed of homogenized organic and mineral soil, the organic layer was important for the P supply to young beech saplings (Hauenstein et al, 2018). Under field conditions, understory vegetation is present and more abundant in P-rich than P-poor beech forests (Rieger et al, 2019). To assess beech P nutrition, the potential competition of understory for nutritional resources needs to be taken into account (Nambiar and Sands, 1993).…”

The interactions among herbaceous diversity, edaphic factors, and topography under typical afforestation in the transition zone between the qinghai–Tibet Plateau and Loess Plateau

“…Poa pratensis) showed higher IVs among all species. In the short term, AP is 'directly' associated with species diversity (Zhou et al 2019); in the long term, the soil P stock could change the plantation use efficiency of P (Rieger et al 2019). In our research, we believe soil P changed the community to one with a high P use efficiency, as P has been proven to be a key growth-limiting nutrient in strongly weathered soil (Laliberté et al 2015).…”

“…The variation of soil properties leads to changes in the composition and traits of herbs, which in turn affect soil characteristics (Laughlin et al 2007). Compared with the tree and shrub layers, the herb layer is more sensitive to soil nutrient change and more competitive in nutrient cycling (Rieger et al 2019). According to previous research on the alpine region and Loess Plateau, the soil nitrogen, phosphorus, potassium, and soil organic carbon (SOC) have significant interactions with herbaceous composition and diversity (Zhang et al 2018;Zhou et al 2019).…”

Aridity and soil properties drive the shrub-herb interactions along drought gradient in desert grassland in Inner Mongolia

“…For example, increasing soil nitrogen content increased shrub-herb competition (She et al 2021). With the increase of soil phosphorus content, the competitive advantage of shrubs decreased, while the competitiveness of herbs increased, which signi cantly increased the herbaceous diversity plant communities (Rieger et al 2019). In the Qinghai-Tibet Plateau, precipitation and temperature affected the facilitation of legume shrubs on herbs through soil nitrogen, and then changed the plant community composition (Cui et al 2023;Ma et al 2020).…”