temperate shrubs Dotaz Zobrazit nápovědu
In view of future changes in climate, it is important to better understand how different plant functional groups (PFGs) respond to warmer and drier conditions, particularly in temperate regions where an increase in both the frequency and severity of drought is expected. The patterns and mechanisms of immediate and delayed impacts of extreme drought on vegetation growth remain poorly quantified. Using satellite measurements of vegetation greenness, in-situ tree-ring records, eddy-covariance CO2 and water flux measurements, and meta-analyses of source water of plant use among PFGs, we show that drought legacy effects on vegetation growth differ markedly between forests, shrubs and grass across diverse bioclimatic conditions over the temperate Northern Hemisphere. Deep-rooted forests exhibit a drought legacy response with reduced growth during up to 4 years after an extreme drought, whereas shrubs and grass have drought legacy effects of approximately 2 years and 1 year, respectively. Statistical analyses partly attribute the differences in drought legacy effects among PFGs to plant eco-hydrological properties (related to traits), including plant water use and hydraulic responses. These results can be used to improve the representation of drought response of different PFGs in land surface models, and assess their biogeochemical and biophysical feedbacks in response to a warmer and drier climate.
Čeleď Anacardiaceae Lindl. (ledviníkovité) je jednou z devíti čeledí řádu Sapindales Dumortier (mýdelníkotvaré). Obsahuje 600 druhů řazených do 70 rodů. Jedná se zejména o keře, stromy nebo liány rozšířené pantropicky, řada druhů však zasahuje i do mírného pásu severní polokoule. Řada zástupců je zemědělsky využívána pro produkci plodů (mango, mombin), u jiných se sbírají, upravují a konzumují semena (pistácie, kešu oříšky). Řada druhů, zejména však zástupci rodu Toxicodendron P. Mill. (jedovatec), má význam toxikologický, další druhy jsou široce využívány v lidovém léčitelství. V předloženém souhrnu je představen nejčastěji kultivovaný zástupce Anacardiaceae v České republice a současně také invazivní druh škumpa orobincová – Rhus hirta (L.) Sudw. Diskutovány jsou sekundární metabolity, jejich farmakologické vlastnosti a farmaceutický význam druhu.
The family Anacardiaceae Lindl. (cashew family, sumac family) is one of the nine families of the order Sapindales Dumortier. It consists of about 600 species classified in 70 genera. Members of the family are shrubs, trees and lianas with pantropical distribution; however, a few species occur in the North Temperate Zone. Some species are used for the production of fruit (mango, mombin), some species are cultivated for edible seeds (pistachio, cashew nuts). Many species are of toxicological importance, especially members of the genus Toxicodendron P. Mill., other species are widely used in folk medicines. This review introduces the most widely cultivated species of the Anacardiaceae family in the Czech Republic and concurrently invasive plant Staghorn Sumac – Rhus hirta (L.) Sudw. The secondary metabolites, their pharmacological properties and pharmaceutical importance of the species are discussed.
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.
- MeSH
- biodiverzita MeSH
- ekosystém MeSH
- klimatické změny MeSH
- ledový příkrov MeSH
- sopečné erupce MeSH
- stromy anatomie a histologie klasifikace fyziologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Korejská republika MeSH
Seven new species and two varieties of Klebsormidium were described using an integrative approach on the base of 28 strains from the poorly studied phylogenetic superclade G. These strains originated from the unusual and exotic habitats (semi-deserts, semi-arid shrublands, Mediterranean shrub and deciduous vegetation, temperate Araucaria forests, peat bogs, dumps after coal mining, maritime sand dunes etc.) of four continents (Africa, South and North America, and Europe). Molecular phylogenies based on ITS-1,2, rbcL gene and concatenated dataset of ITS-1,2-rbcL, secondary structure of ITS-2, morphology, ecology and biogeography, micrographs and drawings of the investigated strains were assessed. Additionally, phylogeny and morphology of 18 Klebsormidium strains from other lineages isolated from the same localities (different vegetation types of Chile and maritime sand dunes of Germany) were investigated for the comparison with representatives of clade G. Clade G Klebsormidium is characterized by distant phylogenetic position from the other Klebsormidium lineages and prominent morphology: four-lobed chloroplasts and mostly short swollen cells in young culture, compact small pyrenoids, curved or disintegrated filaments, unusual elongation of cells in old culture, formation of specific cluster- and knot-like colonies on agar surface, especially prominent in strains isolated from desert regions, from which the group probably originated. Comparison of Klebsormidium diversity from different biogeographic regions showed that the representatives of clade G are common algae in regions of the southern hemisphere (South Africa and Chile) and rare representatives in terrestrial ecosystems of the northern hemisphere. Further investigation of mostly unstudied territories of the southern hemisphere could bring many surprises and discoveries, leading to a change of the present concept that Klebsormidium is cosmopolitan in distribution.
