Några växtgeografiska region-gränser. Betula Nana, Erica Tetralix och Ledum Palustre i Sverige

1925 ◽  
Vol 7 ◽  
pp. 81 ◽  
Author(s):  
Erik Granlund
Biologia ◽  
2010 ◽  
Vol 65 (2) ◽  
Author(s):  
Wojciech Ejankowski

AbstractThe structure and demographic processes were compared in shrub communities to test the effects of vegetation succession on population growth, fecundity and abundance of the dwarf birch (Betula nana L.), which is a rare and endangered plant species in Poland and a glacial relict in Central Europe. The effects of Ledum palustre L. and Vaccinium uliginosum L. were studied in the Linje nature reserve in Chełmińskie Lake District (northern Poland), in three permanent plots on a peat bog. Vegetative growth and reproduction of B. nana were lower in plant communities dominated by L. palustre and V. uliginosum, than in a reference site. Fecundity was also lower, despite the fact that the percentage share of potentially fertile age groups was similar in all study sites. Mortality of ramets was independent of vegetation, both for juvenile and mature stages. The results confirm that B. nana is intolerant of shade, and it is more abundant in vegetation without competitors. Light limitation can lead to its decline, primarily by a decrease in vegetative growth. Sexual reproduction may be negatively affected by shade, but it plays only small role in population growth. Butterfly larvae can destroy inflorescences, and thus contribute to low effectiveness of sexual reproduction. Increasing density of shrubs and trees in peat bogs can reduce the abundance of dwarf birch, and can lead to the extinction of its local populations.


Author(s):  
Tetyana Prykladivska

Кий-острів, що розташований в Онезькій затоці Білого моря (географічні координати 64°00′ п. ш., 37°53′ с. д.) – це виступ гранітної плити, яка залягає на незначній глибині і виходить на поверхню моря у вигляді скель. Геоморфологічні та кліматичні особливості острова, близькість до Північного полярного кола та Арктичної області, зумовили формування на ньому своєрідних природних комплексів, де переважають соснові ліси. Виконані в липні 1984 р. серії описів лісових біоценозів острова дали змогу встановити як основні типи цих лісів (сосняк лишайниковый скальный, сосняк лишайниковый каменистый, сосняк лишайниковый багульниково-вересковый на вершинах сельг [Kucherov, Zverev, 2012; Rupestrian landscapes…, 2008; Rysin, 1975]), так і відповідні їм типи асоціацій (Pinetum cladinosum petraeum, Myrtillus-Calluna-Cladina-Typ, Pinetum uliginosi-vaccinioso-ledosum). Наведений перелік домінантних видів рослин і лишайників нижніх ярусів лісових біоценозів демонструє наявність у їх складі характерних представників бореальної та гіпоарктичної флори. Найбільша частина з них – це класичні бореальні види: Andromeda polifolia L., Arctostaphylos uva-ursi (L.) Spreng., Chamaedaphne calyculata (L.) Moench, Ledum palustre L., Linnaea borealis L., Nardus stricta L. та інші. На другій позиції знаходяться гіпоарктичні види, серед яких Betula nana L., Rubus arcticus L., Rubus chamaemorus L., Cornus suecica L. На поверхнях скель високу частку складають представники відділу Lichenomycota – характерні елементи північних та південних лишайникових тундр, а саме: Cladonia stellaris (Opiz) Pouzar & Vězda, Cladonia sylvatica (L.) Hoffm., Cladonia rangiferina (L.) Weber ex F.H.Wigg., Cetraria islandica (L.) Ach., Peltigera aphthosa (L.) Willd. Зібраний гербарний матеріал (45 зразків 16-ти таксонів) достатньою мірою відображає найбільш характерні риси біоти скельних сосняків Кий-острова та являє собою єдину колекцію видів з північної тайги європейської частини Росії в Гербарії Національного лісотехнічного університету України, який офіційно зареєстрований в міжнародних базах даних під акронімом LWFU.


1986 ◽  
Vol 64 (12) ◽  
pp. 2993-2998 ◽  
Author(s):  
Steven F. Oberbauer ◽  
Nasser Sionit ◽  
Steven J. Hastings ◽  
Walter C. Oechel

Three Alaskan tundra species, Carex bigelowii Torr., Betula nana L., and Ledum palustre L., were grown in controlled-environment chambers at two nutrition levels with two concentrations of atmospheric CO2 to assess the interactive effects of these factors on growth, photosynthesis, and tissue nutrient content. Carbon dioxide concentrations were maintained at 350 and 675 μL L−1 under photosynthetic photon flux densities of 450 μmol m−2 s−1 and temperatures of 20:15 °C (light:dark). Nutrient treatments were obtained by watering daily with 1/60- or 1/8- strength Hoagland's solution. Leaf, root, and total biomass were strongly enhanced by nutrient enrichment regardless of the CO2 concentration. In contrast, enriched atmospheric CO2 did not significantly affect plant biomass and there was no interaction between nutrition and CO2 concentration during growth. Leaf photosynthesis was increased by better nutrition in two species but was unchanged by CO2 enrichment during growth in all three species. The effects of nutrient addition and CO2 enrichment on tissue nutrient concentrations were complex and differed among the three species. The data suggest that CO2 enrichment with or without nutrient limitation has little effect on the biomass production of these three tundra species.


Hereditas ◽  
2004 ◽  
Vol 122 (2) ◽  
pp. 181-184 ◽  
Author(s):  
Kalman Lantai ◽  
Bengt Kihlman

2018 ◽  
Vol 374 (1763) ◽  
pp. 20170395 ◽  
Author(s):  
Barnabas H. Daru ◽  
Elizabeth A. Bowman ◽  
Donald H. Pfister ◽  
A. Elizabeth Arnold

Herbarium specimens represent important records of morphological and genetic diversity of plants that inform questions relevant to global change, including species distributions, phenology and functional traits. It is increasingly appreciated that plant microbiomes can influence these aspects of plant biology, but little is known regarding the historic distribution of microbes associated with plants collected in the pre-molecular age. If microbiomes can be observed reliably in herbarium specimens, researchers will gain a new lens with which to examine microbial ecology, evolution, species interactions. Here, we describe a method for accessing historical plant microbiomes from preserved herbarium specimens, providing a proof of concept using two plant taxa from the imperiled boreal biome ( Andromeda polifolia and Ledum palustre subsp . groenlandicum, Ericaceae). We focus on fungal endophytes, which occur within symptomless plant tissues such as leaves. Through a three-part approach (i.e. culturing, cloning and next-generation amplicon sequencing via the Illumina MiSeq platform, with extensive controls), we examined endophyte communities in dried, pressed leaves that had been processed as regular herbarium specimens and stored at room temperature in a herbarium for four years . We retrieved only one endophyte in culture, but cloning and especially the MiSeq analysis revealed a rich community of foliar endophytes. The phylogenetic distribution and diversity of endophyte assemblages, especially among the Ascomycota, resemble endophyte communities from fresh plants collected in the boreal biome. We could distinguish communities of endophytes in each plant species and differentiate likely endophytes from fungi that could be surface contaminants. Taxa found by cloning were observed in the larger MiSeq dataset, but species richness was greater when subsets of the same tissues were evaluated with the MiSeq approach. Our findings provide a proof of concept for capturing endophyte DNA from herbarium specimens, supporting the importance of herbarium records as roadmaps for understanding the dynamics of plant-associated microbial biodiversity in the Anthropocene. This article is part of the theme issue ‘Biological collections for understanding biodiversity in the Anthropocene’.


1997 ◽  
Vol 75 (1) ◽  
pp. 108-120 ◽  
Author(s):  
Jaanus Paal ◽  
Eli Fremstad ◽  
Tõnu Möls

The effect of nitrogen fertilization on species cover, increment of shrubs, tissue nitrogen, and soil parameters was tested during a 3-year experiment in a low alpine plant community dominated by Betula nana in the Dovre mountains, south-central Norway. The doses used were 1.2 and 6.1 g N/m2, corresponding to 0.72 and 3.6 times, respectively, the annual deposition of nitrogen in southwest Norway. Statistical analysis using SAS ANOVA and GLM procedures were applied to different types of models. The cover of species and growth forms showed no significant response to additional nitrogen supply. The increment of shrubs was not significantly affected by the fertilization, except for the year factor. Incorporation of nitrogen into plant tissue was not evident. No effects were found on soil parameters. Key words: fertilization, alpine tundra, shrubs, nitrogen.


1978 ◽  
Vol 129 ◽  
pp. 1-66
Author(s):  
S Funder

The Holocene stratigraphy in Scoresby Sund is based on climatic change as reflected by fluctuations in fjord and valley glaciers, immigration and extinction of marine molluscs, and the vegetation history recorded in pollen diagrams from five lakes. The histories are dated by C-14, and indirectly by emergence curves showing the patterns of isostatic uplift. From c. 10100-10400 to 9400 yr BP the major fjord glaciers showed oscillatory retreat with abundant moraine formation, the period of the Milne Land Moraines. The vegetation in the ice-free areas was a sparse type of fell field vegetation but with thermophilous elements indicating temperatures similar to the present. From 9400 yr BP the fjord glaciers retreated rapidly in the narrow fjords, the few moraines formed are referred to the Rødefjord stages and indicate topographically conditioned stillstands. At 8000 yr BP the low arctic Betula nana immigrated into the area, and in the period until 5000 yr BP dense dwarf shrub heath grew in areas where it is now absent. In the fjords the subarctic Mytilus edulis and Pecten islandica lived, suggesting a climate warmer than the present. From c. 5000 yr BP the dense dwarf shrub heath began to disappear in the coastal areas, and a 'poor' heath dominated by the high arctic Salix Arctica and Cassiope tetragona expanded. These two species, which are now extremely common, apparently did not grow in the area until c. 6000 yr BP. In lakes in the coastal area minerogenic sedimentation at c. 2800 yr BP, reflecting the general climatic deterioration.


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