Vol.:(0123456789) 1 3 Tropical Ecology https://doi.org/10.1007/s42965-020-00063-z RESEARCH ARTICLE Local edaphic factors infuence leaf nutrient resorption efciency of evergreen and deciduous trees: a case study from montane subtropical old‑growth and regenerating forests of Meghalaya Namita Thapa 1  · Saroj K. Barik 2  · Krishna Upadhaya 3  · N. John Lakadong 1 Received: 20 December 2018 / Revised: 28 October 2019 / Accepted: 18 December 2019 © International Society for Tropical Ecology 2020 Abstract Variation in soil nutrient availability can infuence the functional traits and performance of tree species in a forested land- scape. We tested this hypothesis by studying the variations in leaf-traits, and N- and P-resorption efciencies of a few ever- green (Myrica esculenta, Rhododendron arboretum and Lithocarpus dealbatus) and deciduous (Quercus griffithii, Engel- hardtia spicata and Lyonia ovalifolia) tree species growing in montane subtropical old-growth and regenerating forests of Meghalaya, northeast India, varying in their soil characteristics. Trees of the old-growth forest stand, having greater soil total N and P, proved to be much efcient in their foliar nutrient resorption (mean = 42.0% for N and mean = 82.1% for P) and showed higher leaf nutritional quality compared to the regenerating forest stand. Deciduous species had greater N-resorption efciencies (45.3–49.7%) than the evergreen species (23.6–56.9%) in the old-growth stand. However, in the regenerating stand, the evergreen species were better at resorbing both N (30.6–55.9%) and P (67.9–76.4%) from their leaves than the deciduous species (23.2–40.9% for N and 33.2–52.0% for P). Overall, phosphorus was the limiting nutrient for growth in both the functional groups, with relatively low concentrations in the soils of the two forest stands. The evergreen and deciduous trees in the old-growth forest are found to tightly conserve nutrients with higher leaf N and P concentrations and higher N- and P- resorption efciencies than the regenerating forest stand. The study clearly indicates that soil fertility has profound efect on the internal nutrient cycling of evergreen and deciduous tree species. Keywords Functional groups · Internal nutrient cycling · Nitrogen · Nutrient availability · Phosphorus · Stand-age Introduction Studies on changes in species composition and their nutrient requirements with stand development have been of interest to many researchers (Lehtonen et al. 2004; Tang et al. 2014). The two key nutrients i.e. nitrogen (N) and phosphorus (P) are crucial for the growth of plants in terrestrial ecosystems (van Heerwaarden et al. 2003; Güsewell 2004; Knecht and Göransson 2004; Hagen-Thorn et al. 2006; Elser et al. 2007). Depending on the availability of these nutrients, plants have evolved several nutrient conservation mechanisms to thrive in the ecosystem. The process of nutrient resorption is one such mechanism that enables plants to capture and retain nutrients internally, thereby reducing their dependency on soil nutrient availability (Aerts 1996; Killingbeck 1996; Brant and Chen 2015). In addition, it provides ability to the plants to withstand temporal fuctuations in soil nutrient availability. Nutrient resorption can be quantifed as resorp- tion efciency, which is the percentage reduction of nutri- ent concentration between green and senesced leaves (Distel et al. 2003). According to Chapin and Kedrowski (1983), variations in leaf traits such as specifc leaf area (SLA), leaf mass per unit area (LMA) and leaf nutrient concentrations contribute to variation in nutrient resorption efciencies among diferent plant functional groups. Several authors have emphasized the use of these traits in explaining the diferences exhib- ited by plant species across soil nutrient gradients (Chapin International Society for Tropical Ecology * Saroj K. Barik sarojkbarik@gmail.com 1 Department of Botany, North-Eastern Hill University, Shillong 793022, India 2 CSIR-National Botanical Research Institute, Lucknow, India 3 Division of Environmental Sciences, Department of Basic Sciences and Social Sciences, North-Eastern Hill University, Shillong 793022, India