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• Blinkova O., Żytkowiak R., Wiland-Szymańska J., Sowelo M., Jaźwa M., Ratajczak E., Jagodziński A.M. 2025. Multilevel trait responses of liana Hedera helix L. to environmental gradients in urban forest ecosystems. Scientific Reports 15(1): 40155. https://www.nature.com/articles/s41598-025-23815-0
• Wyka T.P., Robakowski P., Romo A., Boratyński A., Żytkowiak R., Oleksyn J. 2025. Foliar N content parallels increasing aridity in a Mediterranean-Saharan transition zone: evidence from regional and global trends. Journal of Biogeography 52(1): 213-224. https://doi.org/10.1111/jbi.15027
• Dylewski Ł., Adamczyk D., Żytkowiak R., Jagodziński A.M. 2024. Seed mass and seed resources - testing the defense trade-off hypothesis in woody plants. Dendrobiology 91: 32-41. https://doi.org/10.12657/denbio.091.003
• Niemczyk M., Wrzesiński P., Szyp-Borowska I., Krajewski S., Żytkowiak R., Jagodziński A.M. 2024. Coping with extremes: Responses of Quercus robur L. and Fagus sylvatica L. to soil drought and elevated vapour pressure deficit. Science of The Total Environment 948: 174912. https://doi.org/10.1016/j.scitotenv.2024.174912
• Słupianek A., Myśkow E., Kasprowicz-Maluśki A., Dolzblasz A., Żytkowiak R., Turzańska M., Sokołowska K. 2024. Seasonal dynamics of cell-to-cell transport in angiosperm wood. Journal of Experimental Botany 75(5): 1331-1346. https://doi.org/10.1093/jxb/erad469
• Słupianek A., Myśkow E., Kasprowicz-Maluśki A., Dolzblasz A., Żytkowiak R., Turzańska M., Sokołowska K. 2023. Seasonal dynamics of cell-to-cell transport in angiosperm wood. Journal of Experimental Botany, erad469, https://doi.org/10.1093/jxb/erad469
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• Paź-Dyderska S., Żytkowiak R., Jagodziński A.M. 2022. Intra-and interspecific variability of non-structural carbohydrates and phenolic compounds in flowers of 70 temperate trees and shrubs. Forests 13(8): 1256. https://doi.org/10.3390/f13081256
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• Rabska M., Robakowski P., Ratajczak E., Żytkowiak R., Iszkuło G., Pers-Kamczyc E. 2021. Photochemistry differs between male and female Juniperus communis L. independently of nutritional availability. Trees – Structure and Function 35: 27-42. https://doi.org/10.1007/s00468-020-02004-8
• Zadworny M., Mucha J., Bagniewska-Zadworna A., Żytkowiak R., Mąderek E., Danusevičius D., Oleksyn J., Wyka T.P., McCormack M.L. 2021. Higher biomass partitioning to absorptive roots improves needle nutrition but does not alleviate stomatal limitation of northern Scots pine. Global Change Biology 27(16): 3859-3869. https://doi.org/10.1111/gcb.15668
• Zadworny M., Mucha J., Jagodziński A.M., Kościelniak P., Łakomy P., Modrzejewski M., Ufnalski K., Żytkowiak R., Comas L.H., Rodríguez-Calcerrada J. 2021. Seedling regeneration techniques affect root systems and the response of Quercus robur seedlings to water shortages. Forest Ecology and Management 479: #118552. https://doi.org/10.1016/j.foreco.2020.118552
• Mucha J., Zadworny M., Helmisaari H-S., Nihlgård B., Repo T., Żytkowiak M., Małek S., Reich P.B., Oleksyn J. 2020. Fine root classification matters: Nutrient levels in different functional categories, orders and diameters of roots in boreal Pinus sylvestris across a latitudinal gradient. Plant and Soil 447: 507-520. https://doi.org/10.1007/s11104-019-04395-1
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• Rabska M., Pers-Kamczyc E., Żytkowiak R., Adamczyk D., Iszkuło G. 2020. Sexual dimorphism in the chemical composition of male and female in the dioecious tree, Juniperus communis L., growing under different nutritional conditions. International Journal of Molecular Sciences 21: #8094. https://doi.org/10.3390/ijms21218094
• Jankowski A., Wyka T.P., Żytkowiak R., Danusevičius D., Oleksyn J. 2019. Does climate-related in situ variability of Scots pine (Pinus sylvestris L.) needles have a genetic basis? Evidence from common garden experiments. Tree Physiology 39: 573-589. doi:10.1093/treephys/tpy145
• Wigley B.J., Staver A.C., Żytkowiak R., Jagodziński A.M., Wigley-Coetsee C. 2019. Root trait variation in African savannas. Plant and Soil 441: 555-565. https://doi.org/10.1007/s11104-019-04145-3
• Wyka T.P., Zadworny M., Mucha J., Żytkowiak R., Nowak K., Oleksyn J. 2019. Biomass and nitrogen distribution ratios reveal a reduced root investment in temperate lianas vs. self-supporting plants. Annals of Botany 124(5): 777-790. https://doi.org/10.1093/aob/mcz061
• Wyka T.P., Zadworny M., Mucha J., Żytkowiak R., Nowak K., Oleksyn J. 2019. Species-specific responses of growth and biomass distribution to trellis availability in three temperate lianas. Trees – Structure and Function 33(3): 921-932. https://doi.org/10.1007/s00468-019-01828-3
• Dering M., Kosiński P., Wyka T.P., Pers-Kamczyc E., Boratyński A., Boratyńska K., Reich P.B., Romo A., Zadworny M., Żytkowiak R., Oleksyn J. 2017. Tertiary remnants and Holocene colonizers: Genetic structure and phylogeography of Scots pine reveal higher genetic diversity in young boreal than in relict Mediterranean populations and a dual colonization of Fennoscandia. Diversity and Distributions 23(5): 540-555. https://doi.org/10.1111/ddi.12546
• Jankowski A., Wyka T.P., Żytkowiak R., Nihlgard B., Reich P.B., Oleksyn J. 2017. Cold adaptation drives variability in needle structure and anatomy in Pinus sylvestris L. along a 1900km temperate-boreal transect. Functional Ecology 31(12): 2212-2223. https://doi.org/10.1111/1365-2435.12946
• Zadworny M., McCormack M.L., Żytkowiak R., Karolewski P., Mucha J., Oleksyn J. 2017. Patterns of structural and defense investments in fine roots of Scots pine (Pinus sylvestris L.) across strong temperature and latitudinal gradient in Europe. Global Change Biology 23(3): 1218-1231. https://doi.org/10.1111/gcb.13514
• Chmura D.J., Guzicka M., McCulloh K.A., Żytkowiak R. 2016. Limited variation found among Norway spruce half-sib families in physiological response to drought and resistance to embolism. Tree Physiology 36: 252-266. https://doi.org/10.1093/treephys/tpv141
• Wyka T., Karolewski P., Żytkowiak R., Chmielarz P., Oleksyn J. 2016. Whole-plant allocation to storage and defense in juveniles of related evergreen and deciduous shrub species. Tree Physiology 36(5): 536-547. https://doi.org/10.1093/treephys/tpv108
• Skorupski M., Jagodziński A.M., Żytkowiak R., Karolewski P. 2012. Differences in chemical composition of needle and leaf litter from exotic and native tree species stands. Dendrobiology 68: 101-112.
• Wyka T.P., Oleksyn J., Żytkowiak R., Karolewski P., Jagodziński A.M., Reich P.B. 2012. Responses of leaf structure and photosynthetic properties to intra-canopy light gradients: a common garden test with four broadleaf deciduous angiosperm and seven evergreen conifer tree species. Oecologia 170: 11-24. https://doi.org/10.1007/s00442-012-2279-y
• Tjoelker M.G., Oleksyn J., Żytkowiak R., Reich P.B. 2008. Coupling of respiration, nitrogen, and sugars underlies convergent temperature acclimation in Pinus banksiana across wide-ranging sites and populations. Global Change Biology 14(4): 782-797. https://doi.org/10.1111/j.1365-2486.2008.01548.x
• Wyka T., Robakowski P., Żytkowiak R. 2008. Leaf age as a factor in anatomical and physiological acclimative responses of Taxus baccata L. needles to contrasting irradiance environments. Photosynthesis Research 95(1): 87-99. https://doi.org/10.1007/s11120-007-9238-1
• Żmuda M., Karolewski P., Giertych M.J., Żytkowiak R., Bąkowski M., Grzebyta J., Oleksyn J. 2008. The effect of light conditions on leaf injury in underbrush shrubs caused by leaf-eating insects. Acta Scientiarum Polonorum, Silvarum Colendarum Ratio et Industria Lignaria 7(3): 47-57. https://www.forestry.actapol.net/pub/5_3_2008.pdf
  Hobbie S.E., Ogdahl M., Chorover J., Chadwick O.A., Oleksyn J., Żytkowiak R., Reich P.B. 2007. Tree species effects on soil organic matter dynamics: the role of soil cation composition. Ecosystems 10: 999-1018. https://doi.org/10.1007/s10021-007-9073-4
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• Bojarczuk K., Oleksyn J., Karolewski P., Żytkowiak R. 2006. Response of silver birch (Betula pendula Roth.) seedlings to aluminum. Polish Journal of Ecology 54(2): 189-199. https://miiz.waw.pl/pliki/article/ar54_2_03.pdf
• Dickie I.A., Oleksyn J., Reich P.B., Karolewski P., Żytkowiak R., Jagodzinski A.M., Turzanska E. 2006. Soil modification by different tree species influences the extent of seedling ectomycorrhizal infection. Mycorrhiza 16(2): 73-79. https://doi.org/10.1007/s00572-005-0013-x
• Giertych M.J., Karolewski P., Żytkowiak R., Oleksyn J. 2006. Differential defense strategies against herbivore between two pioneer tree species: Alnus glutinosa and Betula pendula. Polish Journal of Ecology 54(2): 181-187. https://miiz.waw.pl/pliki/article/ar54_2_02.pdf
• Hobbie S.E., Reich P.B., Oleksyn J., Ogdahl M., Żytkowiak R., Hale C., Karolewski P. 2006. Tree species effects on decomposition and forest floor dynamics in a common garden. Ecology 87(9): 2288-2297. https://doi.org/10.1890/0012-9658(2006)87[2288:TSEODA]2.0.CO;2
• Giertych M.J., Bąkowski M., Karolewski P., Żytkowiak R., Grzebyta J. 2005. Influence of mineral fertilization on feed quality of oak leaves and utilization efficiency of feed components by the gypsy moth. Entomologia Experimentalis et Applicata 117(1): 59-69. https://doi.org/10.1111/j.1570-7458.2005.00332.x
• Grzebyta J., Karolewski P., Żytkowiak R., Giertych M.J., Werner A., Zadworny M., Oleksyn J. 2005. Effects of elevated temperature and fluorine pollution on relations between the pedunculate oak (Quercus robur) and oak powdery mildew (Microsphaera alphitoides). Dendrobiology 53: 27-33.
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[Articles in Polish]

• Mucha J., Żytkowiak R., Ufnalski K., Oleksyn J. 2023. Dekompozycja – element cyklu życia drzew. Kórniczanin 3: 14.