Trees最新文献

{"title":"Timings of leaf abscission, nitrogen resorption, and autumn coloration across contrasting canopy positions in Acer japonicum","authors":"Kenichi Yazaki,&nbsp;Chunhua Zhang,&nbsp;Hisashi Abe,&nbsp;Mitsutoshi Kitao","doi":"10.1007/s00468-026-02739-w","DOIUrl":"10.1007/s00468-026-02739-w","url":null,"abstract":"<div><h3>Key message</h3><p>Abscission zone development during late autumn is independent of a given light environment and anthocyanin-based coloration in a fullmoon maple, a seasonal deciduous species.</p><h3>Abstract</h3><p>Similar to the decline in leaf function during autumn senescence, the timing of formation and development of the abscission zone (AZ) in the leaf petiole is crucial for leaf longevity. However, the link between AZ development and leaf function decline remains unclear. Autumn leaf coloration has been proposed as a potential consequence of AZ development, possibly resulting from sugar accumulation caused by AZ-induced phloem blockage, but evidence for impaired phloem transport is lacking. To clarify the relationship between AZ development, anthocyanin accumulation, and changes in leaf functional traits, we tracked anatomical changes in the AZ of adult fullmoon maple (<i>Acer japonicum</i> Thunb.), alongside dynamics of nitrogen (N), non-structural carbohydrates, and pigments estimated from reflectance spectra. Traits were compared between leaves under open and shaded conditions to assess the influence of leaf productivity. We found no relationship between AZ development and anthocyanin accumulation. In contrast, sugar accumulation, N resorption, and chlorophyll degradation synchronized with AZ cell degradation. N resorption continued until leaf shedding, suggesting phloem remains functional despite AZ progression. Although the seasonal pattern and absolute amount of anthocyanin accumulation exhibited clear light dependency, the seasonal pattern of AZ development was identical under both light conditions, suggesting genetic control of AZ development. This study provides the first direct evidence that AZ development, a key process in determining leaf longevity, occurs independently of light environment and anthocyanin-based coloration.</p></div>","PeriodicalId":805,"journal":{"name":"Trees","volume":"40 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00468-026-02739-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147362819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Calcium supply alters aquaporin transcription and enhances water deficit resilience in a Eucalyptus hybrid","authors":"Patricia Ramalho de Barros,&nbsp;Samuel Vasconcelos Valadares,&nbsp;Alice Pita-Barbosa,&nbsp;Wagner L. Araújo,&nbsp;Nairam Félix de Barros","doi":"10.1007/s00468-025-02712-z","DOIUrl":"10.1007/s00468-025-02712-z","url":null,"abstract":"<div><h3>Key message</h3><p>Calcium plays a role in modulating aquaporin expression, reducing oxidative stress, preserving chlorophyll content, and maintaining membrane integrity, suggesting it may enhance eucalypt resilience to water restriction.</p><h3>Abstract</h3><p>Drought is a significant abiotic stress that severely impacts the growth and productivity of forests worldwide. This study investigates the role of calcium (Ca²⁺) supply in modulating aquaporin (AQP) gene expression and mitigating oxidative stress in eucalypt (<i>Eucalyptus urophylla</i> × <i>Eucalyptus camaldulensis</i>) under water restriction. Three-month-old eucalypt seedlings were subjected to water restriction, with or without Ca²⁺ supplementation. We measured mRNA expression levels of five aquaporin isoforms (<i>PIP1;2, PIP1;3, PIP2;1, PIP2;2,</i> and <i>PIP2;7</i>), chlorophyll content, and markers of oxidative stress [e.g., hydrogen peroxide (H₂O₂), malondialdehyde (MDA), and the activities of catalase (CAT) and superoxide dismutase (SOD)]. Our findings reveal that initial water restriction upregulated the expression of <i>PIP1;2, PIP2;1, PIP2;2,</i> and <i>PIP2;7</i> in roots, which likely facilitated water uptake and maintained cellular hydration. However, under prolonged water limitation, plants supplemented with Ca²⁺ showed downregulation of these PIPs, possibly as a protective mechanism to reduce water loss. In contrast, plants without Ca²⁺ exhibited an upregulation of <i>PIP1;2, PIP1;3</i>, and <i>PIP2;7</i> under prolonged water deficit. Ca²⁺ supplementation also played a crucial role in preserving chlorophyll content and reducing oxidative damage under water limitation. Plants supplemented with Ca²⁺ had lower levels of H₂O₂ and MDA, reduced oxidative damage and membrane permeability, alongside increased CAT activity, which suggests an enhanced oxidative response. Our results provide new insights into how Ca²⁺ enhances eucalypt responses to water deprivation, enhancing our understanding of the function of Ca²⁺ in drought responses.</p></div>","PeriodicalId":805,"journal":{"name":"Trees","volume":"40 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00468-025-02712-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147336100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of air pollution tolerance and dust capturing capacity of various plant species of Mirzapur region, India","authors":"Divya Singh,&nbsp;Rajani Srivastava,&nbsp;Kuldeep Bauddh","doi":"10.1007/s00468-026-02751-0","DOIUrl":"10.1007/s00468-026-02751-0","url":null,"abstract":"<div>\u0000 \u0000 <p>With an increase in urbanization and industrialization, the number of automobiles has also increased significantly, contributing the largest percentage to air pollution. Air pollution has a detrimental impact on both human health and the environment, making it a significant global concern. Plantation along roads and highways is the first line of defence, as it reduces the negative impact, improves air quality, and provides thermal comfort. The present study was conducted at three different sites of the city of Mirzapur, located in Uttar Pradesh, India. The sites were Rajiv Gandhi South Campus (RGSC), residential areas of Mirzapur (MRA), and the state highway (SH). The study aims to assess the Air Pollution Tolerance Index (APTI), Anticipated Performance Index (API), and Dust Capturing Capacity (DCC) of twelve commonly found species at all three sites. Studies suggested that <i>Mangifera indica</i>, <i>Ficus religiosa</i>, and <i>Azadirachta indica</i> have the highest APTI, while <i>Acacia catechu</i> had the least APTI at all three sites. <i>M. indica</i> and <i>F. religiosa</i> were excellent performers according to their API score at all three sites. DCC was highest in <i>Butea monosperma</i>, <i>Calotopis procera</i>, <i>Alstonia scholaris</i>, <i>M. indica</i>, and <i>F. religiosa</i> at all the sites. Pearson’s correlation analysis revealed a significant relationship of APTI with relative water content (RWC) and ascorbic acid content (AA), whereas a positive correlation of DCC was observed with RWC, AA, and APTI, while a negative correlation was observed with total chlorophyll content (Tch). The linear regression plot shows the strongest positive relationship of APTI with AA. The study recommends air pollution-tolerant plant species for designing sustainable urban forestry and green belts that can reduce pollution and vehicular emissions and improve environmental health.</p>\u0000 </div>","PeriodicalId":805,"journal":{"name":"Trees","volume":"40 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147341906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ex situ experiments with Rhizophora mangle: what is the ideal sample and plot size?","authors":"Ully Depolo Barcelos,&nbsp;Edilson Romais Schmildt,&nbsp;Andreia Barcelos Passos Lima Gontijo,&nbsp;Mônica Maria Pereira Tognella","doi":"10.1007/s00468-026-02740-3","DOIUrl":"10.1007/s00468-026-02740-3","url":null,"abstract":"<div>\u0000 \u0000 <p>Sample and plot size are two pertinent questions in experiments with <i>Rhizophora mangle</i> L. propagules that this study aimed to address. Our analysis was performed with 1,724 propagules collected in six different years in the same mangrove. Individual fresh mass (g), length (cm) and apical, median, and basal diameter (mm) were recorded for each propagule. After descriptive statistics, associated with linear correlation analyses and normality tests, sample and sizing methodologies were defined. For non-experimental designs with <i>R. mangle</i> propagules, we used interval bootstrapping to determine the required propagule amount, providing an abacus and equations for decision-makers to dimension their samples according to errors tolerated around means, for example employing a random collection sample with coefficient of variation of 25% and selection of 10% error, 25 propagules are needed. In designed experiments, plot size was defined as the number of propagules per experimental unit based on the objective. The Hatheway method was used to determine the appropriate number per plot for both fully randomized and randomized block designs. Our results provide a clear ideal range: for a common experimental setup (e.g., 5 treatments, 5 replications and 15% precision), the suitable plot size is 29 propagules per plot for a fully randomized and 30 for a randomized design. The study provides practical guidance for experimental planning in restoration and ecology studies. The developed methodology underscores the importance of a rigorous statistical approach in ensuring replicability and validity of <i>ex situ</i> studies with <i>R. mangle</i> propagules.</p>\u0000 </div>","PeriodicalId":805,"journal":{"name":"Trees","volume":"40 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00468-026-02740-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147341753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unraveling vertical stem CO2 efflux variability in Norway spruce: A decadal perspective","authors":"Eva Darenova,&nbsp;Petr Horáček,&nbsp;Manuel Acosta,&nbsp;Marek Fajstavr,&nbsp;Jan Krejza","doi":"10.1007/s00468-026-02749-8","DOIUrl":"10.1007/s00468-026-02749-8","url":null,"abstract":"<div><h3>\u0000 <b><i>Key message</i></b>\u0000 </h3><p>Stem CO₂ efflux varies in the vertical profile depending mostly on the variability in stem growth rate and the vertical pattern changes with tree age.</p><h3>Abstract</h3><p>Stem CO₂ efflux (<i>E</i>_A) from trees exhibits both temporal and vertical variability. <i>E</i>_A is often measured only at the breast height, making it challenging to accurately upscale these measurements to represent the entire ecosystem. This study examines the potential drivers behind the <i>E</i>_A vertical variability and evaluates the long-term changes in the <i>E</i>_A ratio between two fixed heights. <i>E</i>_A was monitored in two Norway spruce trees over eight growing seasons within a ten-year period (2005–2014). Measurements were carried out simultaneously at three heights (1.3, 3.2, and 4.5 m since 2005 till 2009 and 1.3, 4.5, and 7.5 m since 2011 till 2014) using an automated chamber system. Moreover, meteorological measurements and wood formation analyses were provided. Overall, <i>E</i>_A generally increased with the height, though the pattern differed between trees. Assuming that <i>E</i>_A at 1.3 m was representative of the whole stem resulted in underestimating the seasonal temperature-normalized <i>E</i>_A by 5.3% in one tree and 16.6% in the other. Such variation makes it difficult to generalize the findings. A stem temperature gradient along the stem would contribute to a maximum increase in <i>E</i>_A of 4.3%. Conversely, sap flow, which is understood to transport produced CO₂ to the upper parts of the stem, had no apparent effect on the vertical variation of <i>E</i>_A. Our findings suggest that the vertical variation in <i>E</i>_A is primarily driven by the differences in stem growth, with the stem positions below the crown clearly distinguishable from those at the crown base and within the crown. Moreover, the differences in <i>E</i>_A between 4.5 m and 1.3 m were not constant, showing a gradual decrease over time. This adds further uncertainty when generalizing observed vertical <i>E</i>_A patterns over longer timescales.</p></div>","PeriodicalId":805,"journal":{"name":"Trees","volume":"40 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00468-026-02749-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147340909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The relationship between litterfall and stand characteristics in pine forests of the northeastern East European Plain","authors":"Andrey Osipov,&nbsp;Mikhail Kuznetsov","doi":"10.1007/s00468-026-02750-1","DOIUrl":"10.1007/s00468-026-02750-1","url":null,"abstract":"<div>\u0000 \u0000 <p>Litterfall plays a fundamental role in soil formation, the maintenance of soil fertility, and nutrient cycling. The objective of study was to characterize tree litterfall in Scots pine forests located in the northeastern part of the East European Plain and to assess its relationship with stand structural attributes. Long-term investigations were conducted across Scots pine forests representing three distinct types: <i>Lichen</i>, <i>Myrtillus</i> and <i>Sphagnum</i> using litter traps. Throughout the observation period, litterfall input remained relatively constant. Forest type exerted a significant influence on both the share of individual litter fractions and total litterfall. Specifically, the total quantity of tree litter in <i>Sphagnum</i> pine forests was 2.1–2.3 times lower than in <i>Myrtillus</i> and <i>Lichen</i> pine forests, which exhibited comparable values. No significant correlation was identified between stand density and the total litterfall or its individual fractions. In contrast, significant correlations were observed with other stand parameters, including growing stock, total basal area, and biomass components: foliage (needles and leaves), crowns (branches and foliage), branches, bark, and aboveground biomass. Regression equations were developed linking litterfall input to pine stand characteristics, which proved to be statistically robust predictors. Growing stock (R² ranging from 0.72 to 0.87) and basal area (R² ranging from 0.65 to 0.82) emerged as reliable variables for estimating both total and fractional litterfall in pine stands. The findings of this study can be effectively utilized to improve assessments of carbon cycling in pine forests, particularly when integrated with forest inventory data.</p>\u0000 </div>","PeriodicalId":805,"journal":{"name":"Trees","volume":"40 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147340908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Photosynthates in mature Picea meyeri are preferentially allocated to nonstructural carbohydrate storage at the treeline and to growth at low altitudes on Luya Mountain, Northern China","authors":"Xianji Yang,&nbsp;Yuan Jiang,&nbsp;Xinyuan Ding,&nbsp;Minghao Cui,&nbsp;Jingling Liu","doi":"10.1007/s00468-026-02736-z","DOIUrl":"10.1007/s00468-026-02736-z","url":null,"abstract":"<div><h3>\u0000 <b><i>Key message</i></b>\u0000 </h3><p><b>Low-altitude trees allocate a greater proportion of assimilated carbon to growth, whereas treeline trees preferentially allocate carbon to storage to cope with environmental constraints.</b></p><h3>Abstract</h3><p>Photosynthetic rates and growth rates regulate tree source–sink dynamics, yet their effects on nonstructural carbohydrates (NSCs) in trees remain unclear. We monitored mature <i>Picea meyeri</i> in situ for two years in both treeline and low-altitude habitats. We compared the seasonal dynamics of NSCs in the needles, branches, stems, and roots and evaluated the effects of the net photosynthetic rates (P_n) and growth rate on NSCs in different tree organs. The results revealed that (1) needle and branch growth at the treeline was significantly lower than that at low altitudes; however, the mean concentrations of soluble sugars, starch, and NSCs in all organs were greater at the treeline. Moreover, the mean P_n in the trees did not differ significantly between the two habitats; (2) the soluble sugar concentrations in the trees were generally negatively correlated with the growth rate, whereas the starch concentrations tended to be positively correlated with the growth rate; (3) the relationships between the NSCs and the growth rate were stronger in the low-altitude trees than in those at the treeline; and (4) the NSC concentrations were negatively correlated with the P_n at low altitudes but positively correlated at the treeline. Overall, our findings suggest that low-altitude trees allocate a greater proportion of assimilated carbon to growth, whereas treeline trees preferentially allocate carbon to storage to cope with environmental constraints. This work provides new insights into the habitat-dependent carbon allocation strategies of mature trees and offers a scientific basis for predicting forest responses to future climate change.</p></div>","PeriodicalId":805,"journal":{"name":"Trees","volume":"40 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147340911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of tree size and foliage structure on egg-laying patterns of the pine processionary moth in Aleppo pine forests","authors":"Mouffek Guadguad,&nbsp;Mohamed Sbabdji,&nbsp;Xoaquín Moreira","doi":"10.1007/s00468-026-02747-w","DOIUrl":"10.1007/s00468-026-02747-w","url":null,"abstract":"<div><h3>\u0000 <b><i>Key message</i></b>\u0000 </h3><p><b>Larger trees with greater crown volume and higher foliage density attract more PPM egg clutches, highlighting the importance of tree health.</b></p><h3>Abstract</h3><p>The pine processionary moth (PPM), <i>Thaumetopoea pityocampa</i>, is a major pest across North Africa and southwestern Europe, where its larvae cause severe defoliation and long-term damage to pine forests. Female PPMs select host trees for egg deposition using a combination of visual, chemical, and tactile cues, with tree size, vigour, and canopy development playing prominent roles. Larger, healthier trees with abundant foliage generally provide more suitable environments for larval development, offering greater food availability and more stable microclimatic conditions. Beyond tree size, the structural characteristics of foliage—particularly needle size and density—may also influence host selection by affecting both resource quality and the suitability of oviposition sites. Despite previous research emphasizing the importance of tree vigour for PPM oviposition, the relative contribution of tree-level traits versus fine-scale needle characteristics remains poorly understood. To address this gap, we examined host selection patterns in Aleppo pine (<i>Pinus halepensis</i>) by assessing tree traits (height, diameter, crown volume) and needle traits (length, density) across 104 trees at five sites in Algeria. Our results show that larger trees with greater crown volumes hosted significantly more egg clutches and nests, confirming the primacy of tree size in PPM host preference. Needle length, however, had no significant effect on oviposition. In contrast, higher foliage density was associated with a greater number of egg clutches, although it did not influence nest abundance. Overall, these findings underscore the importance of tree size, canopy structure, and foliage density in shaping PPM host selection and suggest that promoting tree health and managing stand structure may help mitigate PPM impacts on Aleppo pine forests.</p></div>","PeriodicalId":805,"journal":{"name":"Trees","volume":"40 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147340912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring factors influencing the height growth of Cunninghamia lanceolata based on bootstrap bayesian network and random forest","authors":"Baoying Wang,&nbsp;Rui Li,&nbsp;Yujun Sun,&nbsp;Ruiting Liang,&nbsp;Zhaoting Zhu","doi":"10.1007/s00468-026-02726-1","DOIUrl":"10.1007/s00468-026-02726-1","url":null,"abstract":"<div>\u0000 \u0000 <p>Tree height is a key indicator of forest growth, yet identifying its drivers remains challenging owing to complex interactions and limited data. We analyzed longitudinal data (2010–2021) from ten permanent 20 × 20 m plots at the Jiangle State-Owned Forest Farm. To address the limitations of small sample sizes, this study proposes a novel integrated framework combining Bayesian hyperparameter-optimized Random Forest (RF) and Bootstrap Bayesian Networks (BN). Based on 23 variables retained after multicollinearity screening, the RF model identified 21 potential predictors, such as diameter at breast height (Dg), stand basal area (BA), and stand density (N). A key methodological contribution was the implementation of the Bootstrap BN with permutation tests, which significantly enhanced model robustness and edge reliability. The results revealed significant interactions: Dg and MAP exerted direct effects on tree height, whereas SDI influenced tree height indirectly through mediation effects. Notably, the proposed Bootstrap BN model achieved an 84% improvement in the Coefficient of Determination (R²) compared to the traditional BN model. These findings demonstrate the effectiveness of the proposed framework in unraveling multidimensional growth mechanisms and provide a solid scientific foundation for implementing density control strategies adapted to local hydrothermal conditions.</p>\u0000 </div>","PeriodicalId":805,"journal":{"name":"Trees","volume":"40 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147340298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Plasticity of second-year Nyssa aquatica seedlings under simulated light competition","authors":"John E. Tracy,&nbsp;Ajay Sharma,&nbsp;Justin McKeithen","doi":"10.1007/s00468-026-02746-x","DOIUrl":"10.1007/s00468-026-02746-x","url":null,"abstract":"<div>\u0000 \u0000 <p><i>Nyssa aquatica</i>, a common wetland species found in floodplains of the southeastern U.S., often forms dense, monospecific stands and is considered shade-intolerant to moderately shade-tolerant. Its regeneration typically occurs when canopy gaps and favorable hydrologic conditions allow seed germination and seedling establishment. Altered hydrology and drier conditions in southeastern floodplains have facilitated encroachment by other bottomland species, which may intensify competition for light and stunt regeneration of <i>N. aquatica</i>. However, there is little empirical evidence of <i>N. aquatica</i> seedling performance in shade. We developed a semi-controlled study to determine whether <i>N. aquatica</i> seedlings are phenotypically plastic and if specific functional traits that influence fitness (i.e., growth rates) are negatively impacted under increasing shade (0%, 60%, 70%, and 90%). Measured parameters of potted second-year seedlings included growth rate, number of leaves, leaf area, internodal distance, and leaf thickness. We hypothesized that seedlings would exhibit plasticity across all measured parameters and that growth rates would decrease with increasing shade levels. Seedlings exhibited plasticity with all parameters except leaves per stem. Radial and height growth peaked under 60% shade, while radial growth was lowest in 90% shade and height growth was lowest in full-sun. These results suggest that <i>N. aquatica</i> seedlings are highly plastic and perform optimally under moderate shade (particularly 60%). A full-sun environment may impose physiological stress, though higher soil moisture in field sites may mitigate the negative response we observed. Given the species’ reduced radial and height growth in 90% shade, it is likely their competitive ability and fitness are reduced in similar field conditions. Interactions between shade tolerance and hydrologic stress (e.g., flooding or drought) may play a more critical role, highlighting the need for further research into these complex ecological dynamics.</p>\u0000 </div>","PeriodicalId":805,"journal":{"name":"Trees","volume":"40 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147340032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}