Modelling the Ecological Niche of a Treeline Tree Species (Betula utilis) in the Himalayas—A Methodological Overview

Forest structure and regeneration of Betula utilis (D. Don) was studied in birch forestlocated in Samagaun valley (3500 – 4000 m) of Manaslu Conservation Area. Vegetationsampling was done by quadrat method. Altogether 40 quadrats were sampled to determinethe Importance Value Index (IVI) of tree species, and distribution pattern of seedlings andsaplings. Regeneration was assessed by density - diameter curve. Four tree species wererecorded from the forest. Betula utilis was the dominant tree species with the highestImportance Value Index (173.22) in mixed Betula forest and 262.96 in pure Betula forestand Abies spectabilis was the co – dominant species (65.95) in mixed Betula forest whileRhododendron campanulatum was the co-dominant species (37.03) in pure Betula forest.Density of Betula utilis increased with increase in elevation where as density of other treespecies decreased with increase in elevation. Mixed Betula forest at lower elevation wasyoung. The density diameter curve of the tree population of Betula utilis, both on mixed andpure forests, deviated slightly from the typical reverse J shaped structure and hence did notshow the sustainable regeneration. The sapling density was higher than seedling density.The distribution of seedlings and saplings were not uniform among the sampling plots.DOI: http://dx.doi.org/10.3126/eco.v20i0.11472ECOPRINT An International Journal of EcologyVol. 20, 2013page: 107-113

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Population Demographic History of a Rare and Endangered Tree Magnolia sprengeri Pamp. in East Asia Revealed by Molecular Data and Ecological Niche Analysis

Forests ◽

10.3390/f12070931 ◽

2021 ◽

Vol 12 (7) ◽

pp. 931

Author(s):

Tong Zhou ◽

Xiao-Juan Huang ◽

Shou-Zhou Zhang ◽

Yuan Wang ◽

Ying-Juan Wang ◽

...

Keyword(s):

East Asia ◽

Chloroplast Dna ◽

Tree Species ◽

Ecological Niche ◽

Demographic History ◽

Natural Populations ◽

Genetic Variations ◽

Endangered Tree ◽

Geographic Distributions ◽

Magnolia Sprengeri

Quaternary climate and environment oscillations have profoundly shaped the population dynamic history and geographic distributions of current plants. However, how the endangered and rare tree species respond to the climatic and environmental fluctuations in the subtropical regions of China in East Asia still needs elucidation. In this study, we collected 36 natural populations of an endangered and rare tree species Magnolia sprengeri Pamp. in subtropical China to determine the demographic history, and modeled the changes of geographic distributions of this species in East Asia based on the MaxEnt ecological niche analyses. In addition, we sequenced three maternally inherited chloroplast DNA fragments (matK, trnH-psbA, and rbcL) for all the natural populations which covered the whole geographic distributions of M. sprengeri. Population genetic analysis showed that the endangered tree species have a low level of chloroplast DNA diversity. However, the genetic variation contribution within populations was greater than that among populations (FST = 0.276), which demonstrated a high level of genetic differentiation. Interestingly, some unique chloroplast DNA haplotypes and higher genetic variations were identified in the Qinling-Daba Mountains, Central China, and Tianmu Mountains of Zhejiang province, East of China in East Asia. Combining with the species distribution modeling, we speculated that these areas might be the potential glacial refugia for the endangered plant M. sprengeri. Phylogeographic analysis demonstrated that the geographic factors (e.g., mountains, rivers, and other isolation barriers) had little effect on the genetic divergence among populations. Ecological niche modeling further revealed that the natural populations of M. sprengeri did not experience significant geographic distribution changes from the last glacial maximum to the present time. These findings are in line with the analysis results of the multimodal mismatch patterns of the chloroplast DNA variations. To protect the endangered species M. sprengeri, in situ and ex situ conservation strategies should be formulated for the natural populations with higher genetic variations.

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Potential geographic distribution and modelling of the ecological niche of Harrisonia abyssinica, a priority medicinal tree species in Benin (West Africa)

Modeling Earth Systems and Environment ◽

10.1007/s40808-021-01236-y ◽

2021 ◽

Author(s):

Raïmantou Egbèyèmi Ogougbé ◽

Relique Ignace Agbo ◽

Bernard Ahamidé ◽

Sylvie Djego-Djossou ◽

Gaudence Julien Djego

Keyword(s):

West Africa ◽

Geographic Distribution ◽

Tree Species ◽

Ecological Niche ◽

Medicinal Tree ◽

A Priority ◽

Potential Geographic Distribution

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Climatic limits for the present European distribution of hornbeam (Carpinus betulus), with special reference to Ukraine

10.1101/506428 ◽

2018 ◽

Author(s):

Volodymyr Tytar

Keyword(s):

Special Reference ◽

Tree Species ◽

Ecological Niche ◽

Ecological Niche Modeling ◽

Climatic Factors ◽

Niche Modeling ◽

Limiting Factor ◽

Carpinus Betulus ◽

Modeling Approach ◽

The Common

In this study, we used a ecological niche modeling approach to detect the importance of diverse climatic parameters in controlling the distribution of forest tree species, exemplified by the common hornbeam (Carpinus betulus L.), with special reference to Ukraine from where digitized data on the species has been scarce. In Ukraine populations of this tree species are found on the edge of its home range and are exposed to extreme climate conditions. The main objectives of the present study were to model the European-wide ecological niche of the common hornbeam and investigate primary climatic factors that control the potential distribution of this tree in Ukraine. Using an ecological niche modeling approach, we consider having reliably modeled the European-wide bioclimatic niche of the common hornbeam for predicting the response of species geographical distribution to climate. Most contributing to the model was the mean monthly PET (potential evapotranspiration) of the coldest quarter, continentality and annual PET. In terms of the Most Limiting Factor, in Ukraine continentality is crucial throughout the majority of the country.

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