Plant Diversity Changes during the Postglacial in East Asia: Insights from Forest Refugia on Halla Volcano, Jeju Island

Understanding how past climate changes affected biodiversity is a key issue in contemporary ecology and conservation biology. These diversity changes are, however, difficult to reconstruct from paleoecological sources alone, because macrofossil and pollen records do not provide complete information about species assemblages. Ecologists therefore use information from modern analogues of past communities in order to get a better understanding of past diversity changes. Here we compare plant diversity, species traits and environment between late-glacial Abies, early-Holocene Quercus, and mid-Holocene warm-temperate Carpinus forest refugia on Jeju Island, Korea in order to provide insights into postglacial changes associated with their replacement. Based on detailed study of relict communities, we propose that the late-glacial open-canopy conifer forests in southern part of Korean Peninsula were rich in vascular plants, in particular of heliophilous herbs, whose dramatic decline was caused by the early Holocene invasion of dwarf bamboo into the understory of Quercus forests, followed by mid-Holocene expansion of strongly shading trees such as maple and hornbeam. This diversity loss was partly compensated in the Carpinus forests by an increase in shade-tolerant evergreen trees, shrubs and lianas. However, the pool of these species is much smaller than that of light-demanding herbs, and hence the total species richness is lower, both locally and in the whole area of the Carpinus and Quercus forests. The strongly shading tree species dominating in the hornbeam forests have higher leaf tissue N and P concentrations and smaller leaf dry matter content, which enhances litter decomposition and nutrient cycling and in turn favored the selection of highly competitive species in the shrub layer. This further reduced available light and caused almost complete disappearance of understory herbs, including dwarf bamboo

Directional turnover towards larger-ranged plants over time and across habitats

Species turnover is ubiquitous. However, it remains unknown whether certain types of species are consistently gained or lost across different habitats. Here, we analysed the trajectories of 1827 plant species over time intervals of up to 78 years at 141 sites across mountain summits, forests, and lowland grasslands in Europe. We found, albeit with relatively small effect sizes, displacements of smaller- by larger-ranged species across habitats. Communities shifted in parallel towards more nutrient-demanding species, with species from nutrient-rich habitats having larger ranges. Because these species are typically strong competitors, declines of smaller-ranged species could reflect not only abiotic drivers of global change, but also biotic pressure from increased competition. The ubiquitous component of turnover based on species range size we found here may partially reconcile findings of no net loss in local diversity with global species loss, and link community-scale turnover to macroecological processes such as biotic homogenisation

Tree growth response to recent warming of two endemic species in Northeast Asia

The impact of climatic change on forest ecosystems has received considerable attention, but our understanding of the modulation of this impact by elevational differences and by species interaction is still limited. Here, we analyse tree-ring-based growth-climate relationships for two dominant tree species along an 800-m elevational gradient on Jeju Island, South Korea. Both species, broadleaf Quercus mongolica (QUMO) and coniferous Abies koreana (ABKO), grow at the southern end of their distributional range and they have adjacent altitudinal ranges. We use static and moving bootstrapped correlation analysis to identify the effect of recent warming on their growth. QUMO is primarily positively influenced by moisture during the previous autumn at its upper elevational distribution. Recent warming, however, has diminished this relationship, while the enhancing impact of warm and dry summer conditions on QUMO growth has increased. These recent shifts in growth-climate relationship suggest an upward migration potential for QUMO due to warming-enhanced growth at higher elevations. ABKO growth, on the contrary, is primarily reduced by high winter and summer temperatures. This negative relationship has become more explicit in recent decades, particularly at lower elevations. At the highest elevation, however, ABKO growth-temperature relationship has consistently become more positive in the most recent decades. In the elevational zone where ABKO and QUMO co-exist, warming plays a primary role in ABKO growth reduction, while QUMO growth increases and thus induces a potential upward migration of QUMO. This combined effect can lead to population decline of ABKO. Our results significantly enhance our understanding of the impact of climate warming on two interacting species and provide information necessary for adaptation strategies to preserve declining ABKO populations.Grantová Agentura České Republiky12 month embargo; published online: 27 April 2020This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Improved syntheses of P2X7 ligands based on substituted benzyl amide of pyroglutamic acid motif labelled with iodine-123 or iodine-125

Abstract: P2X7 sites are emerging targets for molecular imaging research, notably in the context of neurodegeneration and inflammatory conditions. Therefore, we prepared a precursor for (radio)iodination of the P2X7 ligand VPGIS191. We then developed a radioiodination method with 123I for SPECT with a radiochemical yield of 71 ± 13% and 125I for autoradiography with a radiochemical yield of 85 ± 6% Autoradiography of [125I]VPGIS191 in mouse brain cryostat sections demonstrated approximately 36 nM binding affinity and Bmax of approximately 400 pmol/gram tissue for P2X7 binding sites. VPGIS191 (cis) had a two-fold lower affinity compared to its geometric trans-isomer TZ6019.</p

Comparison of stand characteristics and functional traits of woody species between three forest types on Halla Volcano, South Korea.

<p>Means sharing the same lowercase superscript letter are not significantly different at <i>P</i> < 0.05 (ANOVA followed by Tukey post- hoc tests).</p

Comparison of transmitted direct radiation, maximum tree height, specific leaf area (SLA), leaf dry matter content (LDMC) and leaf N and P concentrations (LNC, LPC) of woody species among three forest types on Halla Volcano, South Korea.

<p>For significant differences, see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0033065#pone-0033065-t003" target="_blank">Table 3</a>.</p

Comparison of abiotic (altitude, topographical indices and soil physico-chemical parameters) and biotic variables (species richness of different life-forms) between three forest types of Halla Volcano, South Korea.

<p>Means sharing the same lowercase superscript letter are not significantly different at <i>P</i> < 0.05 (ANOVA followed by Tukey post-hoc tests). Variables without superscript letters were not tested.</p

Comparison of soil reaction and concentration of soil nutrients between three forest types on Halla Volcano, South Korea.

<p>Boxes represent 25–75% of values, black dots medians, whiskers 1.5 interquartile ranges, and open dots outliers. For significant differences, see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0033065#pone-0033065-t001" target="_blank">Table 1</a>.</p

Vascular plant species composition of three forest types (Ca, <i>Carpinus</i>; Qu, <i>Quercus</i>; Ab, <i>Abies</i>) studied along an altitudinal gradient from 550 to 1940 m on Halla Volcano, Jeju Island, South Korea.

<p>Numbers are percentage frequencies of species occurrence; dots indicate absence. For trees, occurrences in both canopy and understory are counted. Diagnostic species with the phi coefficient of association > 0.3 are in bold. Dominant species (percent cover 50% in at least 3% of relevés) are in italic.</p

Sample-based rarefaction curves showing an increase in the number of species encountered in three forest types on Halla Volcano, South Korea with growing number of plots for all vacular plants and individual life forms.

<p>Sample-based rarefaction curves showing an increase in the number of species encountered in three forest types on Halla Volcano, South Korea with growing number of plots for all vacular plants and individual life forms.</p