Carex Sylvatica Research Articles

A Hanság gyertyános-tölgyesei (Scillo vindobonensi-Carpinetum)

The present study presents the associations of hornbeam-oak forests (Scillo vindobonensi-Carpinetum) in the northwestern part of Hungary based (Hanság) on 50 cenological images. We are faced with an azonal association moderately influenced by groundwater. Some submontane elements are striking in their stocks, which are generally rare in the Great Plains. In particular, Fagetalia elements are common: Actaea spicata, Adoxa moschatellina, Aegopodium podagraria, Allium ursinum, Anemone ranunculoides, Asarum europaeum, Athyrium filix-femina, Carex pilosa, Carex sylvatica, Circaea lutetiana, Corydalis cava, Corydalis pumila, Epipactis helleborine agg., Gagea lutea, Galanthus nivalis, Galeobdolon luteum, Galium odoratum, Hedera helix, Listera ovata, Milium effusum, Pimpinella major, Polygonatum multiflorum, Pulmonaria officinalis, Salvia glutinosa, Sanicula europaea, Scilla vindobonensis, Stachys sylvatica, Vinca minor, Viola reichenbachiana etc. These plants are probably remnants of the former "Beech I period" (2500 BC to 800 BC) with cooler, wetter and more even climates.

Синтаксономический обзор мезофитных широколиственных лесов союза Aceri campestris–Quercion roboris Bulokhov et Solomeshch in Bulokhov et Semenishchenkov 2015 Юго-Запада России

Mesophilous broad-leaved forests predominating in south-western part of Russia were included in alliance Aceri campestris–Quercion roboris Bulokhov et Solomeshch in Bulokhov et Semenishchenkov 2015, association Fraxino excelsioris–Quercetum roboris Bulokhov et Solomeshch 2003 and three geographic subassociations. The subassociation F. e.–Q. r. typicum Bulokhov et Solomeshch 2003 in Bulokhov et Semenishchenkov 2015 unites communities occurring mainly in the broad-leaved forests zone of the Central Russian Upland. The subassociation F. e.–Q. r. stellarietosum nemori Semenishchenkov et al. 2015 occurs in the northern part of the association range in the zone of broad-leaved forests and close to the southeastern border of the hemiboreal subzone. Mesophilous broad-leaved forests occurring in the forest-steppe zone of the Central Russian Upland were included in the subass. F. e.–Q. r. crataegetosum curvisepalae Semenishchenkov in Bulokhov et Semenishchenkov 2015. The geographical distribution of the syntaxa is related to the climate continentality gradient — from the subass F. e.–Q. r. crataegetosum curvisepalae (the largest continentality indices) to the subass. F. e.–Q. r. stellarietosum nemori (the smallest continentality indices). The associations Aceri campestris–Tilietum cordatae Zaugolnova et Braslavskaya 2003 (nom. inv.) from the Kaluga and Tula Regions (Zaugolnova, Braslavskaya, 2003) and Aceri campestris–Quercetum roboris (nom. inv.) (var. Acer tataricum) described from the Voronezh Region (Starodubtseva, Khanina, 2009) were included in the association Fraxino excelsioris–Quercetum roboris after comparative syntxonomical analysis. On the basis of a comparative analysis, diagnostic combinations of subassociations were compiled, consisting of species with constancy above 20 % and values of the statistical φ-coefficient for selections above 20: F. e.–Q. r. stellarietosum nemori — Carex sylvatica (5059.9), Equisetum hyemale (2842.3), Galeobdolon luteum (10087.4), Matteucia struthiopteris (4257.7), Ranunculus cassubicus (5857.9), Stellaria nemorum (3349.6); F. e.–Q. r. crataegetosum curvisepalae — Acer tataricum (5362.0), Crataegus rhipidophylla (5964.0), Poa nemoralis (2736.9), Pyrus pyraster (3840.8), Scilla siberica (4558.4), Viola odorata (3440.5). Analysis of the differentiaal table of mesophilous broad-leaved and spruce-broad-leaved forests syntaxa made it possible to conclude that associations previously (Onyshchenko, 2009) assigned in Ukraine to alliance Scillo sibericae–Quercion roboris have a high floristic similarity with the syntaxa of Aceri campestris–Quercion roboris from the South-West of Russia, especially in the forest-steppe part of its range. Selections of three subassociations of the association Mercurialo perennis–Quercetum roboris from Ukraine floristically close to the syntaxa of alliance Querco roboris–Tilion cordatae from the South-West of Russia. In the dendrogram of cluster analysis, the compared syntaxa are grouped into two blocks corresponding to the rank of alliances: Aceri campestris–Quercion roboris and Querco roboris–Tilion cordatae. Based on the review, the authors believe that the «Hierarchical floristic classification system…» (Mucina et al., 2016) may be amended in terms of recognizing the syntaxonomical independence of the alliance Aceri campestris–Quercion roboris and its geographical interpretation. Derivative communities disturbed by humans in the place of mesophylous broad-leaved forests are classified as anthropogenic variants and non-rank «communities» named after the dominant species: Betula pendula, Populus tremula, Tilia cordata. Forests with a poor floristic composition, in which the diagnostic species of association and subassociation drop out of the coenoflora are classified as inops variants. They are characterized by a noticeable decrease in the average floristic saturation in comparison with typical communities. Derivative forests with a predominance of Betula pendula have a higher species richness in comparison with aspen or linden forests, as well as typical phytocoenoses of the association.

Enjoying tranquility — Development of ground vegetation after cessation of management in forests on loamy soils in Flanders (Belgium)

AbstractQuestionsManaged forests often show a more homogeneous age structure compared to unmanaged forests, but also a higher share and frequency of canopy and soil disturbances due to harvest operations. Here, we investigate what happens when non‐intervention is introduced in formerly managed forests: Was there a significant decrease in vascular plant species richness? Which species were particularly affected? Are there non‐random shifts in species composition? Were typical shade‐tolerant forest species also jeopardized due to prolonged deep shade? LocationFour recently installed strict reserves in Atlantic to Sub‐Atlantic lowland oak and beech forests on fertile loess soils east and southwest of Brussels (Belgium).MethodsWe compared vegetation relevés in permanent plots (183 plots of 16 m × 16 m) with a 10‐year interval. Total species richness per site was derived from rarefaction curves; significance of differences in species richness and composition at plot level were tested using paired t tests and Wilcoxon signed rank tests. Non‐metric multidimensional scaling analysis (NMDS) was used to check for non‐random shifts in species composition.ResultsWe registered significant declines in species richness both at reserve and plot level. This decline was not random, but strongly dependent on ecological traits and strategies, with strong declines in light‐demanding gap phase‐associated species like Lonicera periclymenum and Deschampsia cespitosa, and species requiring soil disturbance, such as Juncus effusus and Carex sylvatica. Shade‐tolerant mesic species like Anemone nemorosa and Allium ursinum clearly increased in frequency and cover, despite strong declines in previous decades.ConclusionThe effect of lower disturbance frequency leading to continued closed canopy, against a background of reduced atmospheric deposition, induces the development of a ground vegetation with lower species richness, due to decrease of species related to disturbance, but with higher dominance and cover of characteristic species of mesic lowland oak and beech forests.

The Regional Aspects of Biodiversity Preservation under Oil Deposit Exploitation and Oil Transportation

The structure and composition of the forming vegetation at the developed oil field in Western Siberia is considered. The absence of pathologies in plants in reclaimed and self-growing developed areas and the growth of Dactylorhiza maculata (a specially protected plant from the Khanty-Mansi AO Red Book) in the post-technogenic territory testify to the restoration of biodiversity and environmental safety of the emerging post-technogenic communities. Dactylorhiza baltica populations from the Red Book of the Russian Federation have been identified on the Russian Plain in the Leningrad and Yaroslavl Regions in the protected area of oil pipelines. In addition, in the Yaroslavl region, populations of Neottia nidus-avis, Platanthera bifolia, Glyceria lithuanica, Carex sylvatica, Dactylorhiza incarnata, Dactylorhiza maculata, Dactylorhiza fuchsii, Listera ovata, Ophioglossum vulgatum, Veratrum lobelianum, were found. These species are especially protected in the Yaroslavl region. The characteristics of their populations are given: the number of locations, the number of specimens, biotopes. The areas of various grassy biotopes in forest regions are increased through the length of treeless and protected spaces above oil pipelines. Thus these treeless spaces contribute to the conservation of rare and endangered edge-meadow, meadow and bog-meadow plants. Measures for the conservation and restoration of populations of specially protected species are recommended. A suggestion is made about the necessity to expand the assortment of sown plant species when carrying out reclamation work on post-technogenic lands using indigenous species for sowing seeds.

The conditions and methods of biological diversity preservation and restoration on post-technogenic lands

Oil production, as well as the transportation of oil and gas through pipeline systems, cause the destruction and man-made transformation of the natural ecosystems of Northern Eurasia, an increase in the area of disturbed lands, and a reduction in the habitats of specially protected plant species. In this regard, the most significant measures for biological diversity are the identification of conditions for the growth of populations of rare plants in man-made biotopes and the development of methods for their conservation and restoration. 12 species (Carex sylvatica, Dactylorhiza baltica, D. fuchsii, D. incarnata, D. maculata, Fragaria moschata, Glyceria lithuanica, Listera ovata, Neottia nidus-avis, Ophioglossum vulgatum, Platanthera bifolia, Veratrum lobelianum) from the Red Book of the Yaroslavl region and 1 species (Dactylorhiza baltica) from the Red Book of the Leningrad region were recorded in the protected area of oil pipelines. Moreover,Dactylorhiza balticais listed in the Red Book of the Russian Federation. ForDactylorhiza fuchsii, D. incarnata, D. maculata, Fragaria moschata, at the risk of complete destruction of their biotopes, methods of their transplantation, repatriation and rehabilitation have been developed and transferred to the appropriate Department of the Yaroslavl region. For the restoration of biotopes on bulk sand dams of an oil field in Western Siberia, an experimental study of the wild speciesLeymus arenarieusas a fixative of technogenic sands showed good results.

Stratification of soil organic matter and biota dynamics in natural and anthropogenic ecosystems

Soil organic matter (OM) stratification and macro and micro fauna are both good indicators for the evaluation of soil ecological functioning, which is interrelated with nutrient cycles. To the best of the authors’ knowledge, responses of the degree of OM stratification with soil depth expressed as a ratio, and belowground biota to forest degradation and land cover changes have received little attention, particularly in northern Iran. In this study, five land covers were selected: virgin natural forest dominated by Carpinus betulus and Parrotia persica (natural forest), mono-species oak stand (plantation), land including Citrus sinensis and Citrus tangerina trees (garden), land dominated by Brachypodium pinnatum and Carex sylvatica (rangeland), and land including rice cultivation (agriculture) to examine soil OM stratification ratio, biological dynamics, and nutrients. The aim of this study was to evaluate the effect of natural and anthropogenic sites of Hyrcanian region on soil functions following 32 years of land cover changes. Four soil profiles (25 × 25 cm) were dug along four parallel transects in the central part of each land cover plot. Thus, 16 soil samples for each site were sampled at a depth of 0−10 cm for different soil properties and two depths of 0–10 and 10−20 cm to measure the soil OM and calculate OM stratification ratio (OM surface soil/OM subsurface soil). Seasonal measurements during one year were performed under studied land covers to find the temporal pattern of the soil biological activities. With a descending trend of OM with soil depth, OM stratification ratio was significantly enhanced under plantation and natural forest. Conversion of natural forest to anthropogenic sites significantly decreased the activities of different earthworm ecological groups (i.e., epigeic, anecic, and endogeic), Acarina, collembola, nematode, protozoa, bacteria, and fungi. Two-way ANOVA indicated that in addition to land cover, the season also affected the variability of soil earthworm activities. Compared to the other studied soil organisms, the role of land covers was nearly 1.5–2 times greater than that of the season factor. From the PCA output, the high soil biological activities, OM stratification ratio, and nutrients can be attributed to forest ecosystems (i.e., natural forest and plantation), while the low soil biological activities, OM stratification ratio, and nutrients were imposed by anthropogenic sites (i.e., rangeland, garden, and agriculture). The findings of this study support the importance of preserving natural forests for soil conservation and function.

Nomenclatural remarks on Carex sect. Sylvaticae (Cyperaceae): C. laxula and related names

Our taxonomic and nomenclatural research reveals that the name ‘Carex laxula Tineo ex Boott’ (section Sylvaticae) has not been validly published. Consequently, the oldest available name for the species is Carex paui Sennen. A lectotype for the valid name Carex sylvatica var. laxula Tineo ex Guss. is here designated.

Molecular and morphological data resurrect the long neglected <em>Carex laxula</em> (Cyperaceae) and expand its range in the western Mediterranean

Carex sylvatica subsp. paui is a poorly studied taxon considered endemic from a few places in the western Mediterranean. It has been frequently misidentified as C. sylvatica subsp. sylvatica. To date, it has been reported only from the NE Iberian Peninsula and the NW Africa. We use molecular —nuclear ribosomal and plastid sequences— and morphological data to shed light on the taxonomic circumscription and distribution of this taxon, especially regarding its distinction from the type subspecies. The genetic data support the recognition of C. sylvatica subsp. paui as an independent taxon, and confirm new records from the Balearic and Tuscan archipelagos. It implies a considerable increase in its range and a new taxon for the Italian flora. Strikingly, the morphometric analyses revealed that the Sicilian type specimen ofC. laxula identifies this species with C. sylvatica subsp. paui. We consider that the taxon should be ranked at the species level. Based on the priority of the name C. laxula over C. paui, we subsume C. sylvatica subsp. paui in C. laxula. We also provide notes on the ecology of the species.

Stratification of the ant species (Hymenoptera, Formicidae) in the urban broadleaf woodlands of the city of Kiev

Investigations were carried out in June–August 2012 and 2013 in broadleaf forests and planted stands of the northern red oak Quercus rubra in Kiev. The ant visitation rates of 3–6 most abundant plant species within each vegetation layer were analyzed. In all, 16 species of ants were found in the broadleaf forest (Quercus robur + Acer spp. + Carpinus betulus), with the dominance of three species: Formica rufa, Lasius fuliginosus, and L. emarginatus. Eight ant species occurred in Q. rubra stands with the undergrowth of Acer campestre and A. platanoides; the dominant species were Lasius fuliginosus and L. emarginatus. The northern red oak stands with conspecific undergrowth had only four ant species with no dominants among them. Plants with the highest ant visitation rates in the herbage layer of the broadleaf forest were the invasive Impatiens parviflora and the native Aegopodium podagraria. Ants were rare or absent on the remaining herbs: Impatiens noli-tangere, Carex sylvatica, Stellaria holostea, and Galium odoratum. The herbage layer was mostly visited by influents, the dominants being represented only by Lasius emarginatus. Within the shrub layer, ants most frequently visited the undergrowth of the maple Acer platanoides, often harboring colonies of the aphid Periphyllus lyropictus; the highest visitation rates were recorded in the dominants L. emarginatus and L. fuliginosus. The arboreal layer had the highest visitation rate and was most often visited by the dominants Lasius fuliginosus, L. emarginatus, and F. rufa. The common oak Q. robur was the most visited tree in broadleaf forests. In addition to providing ants with food (colonies of the aphids Lachnus roboris and Stomaphis quercus, and also phytophagous insects and other invertebrates), these trees were used for nesting by the dominants L. fuliginosus and L. emarginatus. The presence of aphid colonies was also typical of ripe trees and undergrowth of the maple A. platanoides, the second-visited tree in broadleaf forests. The common hornbeam Carpinus betulus was the least frequently visited, though some ant species, usually L. emarginatus, nested in the trunks and branches of old trees. The vertical distribution of ants in broadleaf forests and red oak stands formed two clusters: the influents occupied the lower (herbage and shrub) vegetation layers, while the subdominants and dominants occupied the upper (shrub and arboreal) ones. The smallest number of ant species (1 or 2) in all the vegetation layers was recorded in the areas with F. rufa; areas with L. fuliginosus had twice as many species; the greatest numbers of ant species were found in the areas with L. emarginatus and in those without dominants. This pattern may result from different territoriality of the dominants: the strongest in F. rufa (defending the whole territory) and the weaker in the other two species (defending only a part of the territory). Plants of all the vegetation layers varied in their attractiveness to ants. As a result, the layers had a mosaic structure in their vertical (between-layer) and horizontal (between different plant species within one layer) arrangement. From 60 to 100% of plants of certain species were visited by ants while plants of other species were not visited at all. The main reason for visiting plants by ants was the presence of aphid colonies.

Фитоценотическое разнообразие сероольховых лесов на юго-западе Нечерноземья России

In the paper the phytocoenotic diversity of gray alder forests, common in the South-Western Nechernozemye of Russia, is characterized. On the territory of studies A. incana occurs in Bryansk, Kaluga, Smolensk and Orel regions. In the European Russia gray alder forests represented by a lot of forest types described by T. A. Rabotnov (1939), A. A. Nitsenko (1972), V. I. Vasilevich (1998), S. V. Degteva (2002), N. S. Liksakova (2004) etc. At the southeastern border of A. incana distribution in the South-Western Nechernozemye of Russia the gray alder forests are presented by mesophytic and hygrophytic ecologic-dynamic groups. Hygrophytic forests probably represent the azonal-zonal type of forest vegetation which is widespread in the valleys of rivers and streams. They are characterized by the presence and high constancy of hygrophyte and helophytic species. These forests belong to the alliance Alnion incanae, but they have essential floristic differences with hygrophyte alder forests of the Central Europe. Plant communities described from the South-Western Nechernozemye of Russia are characterized by a lack of Western- and Central European species, which are widely represented in Germany, Poland, Slovakia, Czech Republic and partly Ukraine: Acer pseudoplatanus, Carex brizoides, Circaea lutetiana, Chaerophyllum hirsutum, Geranium phaeum, Euonymus europaea, Lysimachia nemorum, Primula elatior, Ranunculus lanuginosus, Sambucus nigra, Viola reichenbachiana. In the Central Europe the communities of the ass. Alnetum incanae include the constantly-varying species: Abies alba, Anthriscus nitida, Astrantia major, Carduus personata, Carex remota, Carpinus betulus, Chrysosplenium oppositifolium, Cruciata glabra, Dactylis polygama, Doronicum austriacum, Euphorbia amygdaloides, Fagus sylvatica, Gentiana asclepiadea, Heracleum sphondylium, Petasites albus, P. hybridus, Prenanthes purpurea, Salvia glutinosa, Senecio nemorensis, S. ovatus, Symphytum cordatum, Valeriana dioica, etc. In communities of the Northern part of European Russia absent some nemoral species: Acer platanoides, Adoxa moschatellina, Ajuga reptans, Brachypodium sylvaticum, Carex sylvatica, Corylus avellana, Daphne mezereum, Galium odoratum, Fraxinus excelsior, Lamium maculatum, Mercurialis perennis, Poa nemoralis, Quercus robur, Ranunculus auricomus, R. cassubicus, Scrophularia nodosa, Stachys silvatica, Tilia cordata, Ulmus glabra. These species are more widely represented in Central European forests, as well as in communities of the South-Western Nechernozemye of Russia – near the southern border of the hemiboreal forests. The results of the floristic comparison do not allow considering our forests to be belong to the ass. Alnetum incanae Lüdi 1921 distinguished for the Central Europe Therefore they are allocated in the new ass. Scirpo sylvatici―Alnetum incanae ass. nov. hoc loco. The plant communities differentiate the block of predominantly helophyte and hygrophyte species characteristic for riparian habitats and communities of wetland forests: Agrostis canina, Calliergon cordifolium, Juncus effusus, Glyceria fluitans, Lycopus europaeus, Scirpus sylvaticus, Solanum dulcamara, Stachys palustris. Two variants of the association were discribed. Chaerophyllum aromaticum var. communities are characterized by the dominance of nitrophilous species Chaerophyllum aromaticum. Var. typica combines typical communities and it has no own diagnostic species. The mesophytic alder forests of the Southern Nechernozemye of Russia represent stages of demutation restoration of the mesic spruce and broad-leaved-spruce forests of the order Fagetalia sylvaticae. The specified successional status does not allow considering the mesophytic communities of a gray alder as an independent association. More correct to refer them to the temporary facies of ass. Rhodobryo rosei―Piceetum abietis Korotkov 1986, similar to the secondary birch and aspen forests representing widespread changes of the mesophytic spruce and broad-leaved-spruce forests. This facies is characterized for three variants established by the dominance of some plant species. The most mesophytic forests are represented by var. Galeobdolon luteum, which differentiated by mesophytic species of spruce and broad-leaved-spruce forests: Galeobdolon luteum, Corylus avellana, Stellaria holostea. Communities with abundant undergrowth of Padus avium, formed along the margins of forest swamps in wet loam, were classified as var. Padus avium. Its diagnostic species are following: Padus avium, Crepis paludosa, Stachys sylvatica. Var. typica combines typical communities and it has no own diagnostic species as well. The floristic peculiarities and a role of the ecological factors in differentiation of syntaxa are demonstrated by the DCA-ordination. Communities of the South-Western Nechernozemye of Russia are largely differentiated from the others on the complex gradient corresponding increase in soil moisture, light and temperature. In general, the DCA-1 axis can be regarded as a complex gradient of continentality, soil richness, and the reaction of the substrate; DCA-2 – soil moisture, temperature, and light.

Molecular and morphological evidence for a new species from South Africa: Carex rainbowii (Cyperaceae)

Carex rainbowii (Cariceae, Cyperaceae), a new species from the Drakensberg mountains (KwaZulu-Natal province), is described and illustrated. It was found in the shady understory of the Afromontane forest in the Cathedral Peak area. An additional, nearby population was also identified based on previously collected herbarium material. Morphological and molecular (cpDNA 5′trnK intron and nrDNA ITS and ETS sequences) data were used to evaluate the taxonomic status of these populations and shed light on their systematic placement. Our data strongly support their taxonomic identity and inclusion in Carex sect. Sylvaticae. The new species can be readily distinguished from other related taxa mainly by the frequently androgynecandrous terminal spike, dense female spikes, hyaline glumes, as well as by some quantitative features. This finding implies a considerable biogeographic disjunction from the mainly Eurasian-North African range of the remaining species of sect. Sylvaticae, a pattern also found in the related sections Ceratocystis, Rhynchocystis and Spirostachyae. Comments are provided on previous misidentifications of C. rainbowii as the closely related Carex sylvatica. Data pertinent to the conservation status of the species are provided.

Effects of roads on understory plant communities in a broadleaved forest in Hyrcanian zone

This study was conducted to assess the effect of forest road as a corridor on local biodiversity. For this purpose, 10 segments in a 10 year-old road were selected in Neka-Zalemrood forest in Hyrcanian zone. At each of the segments, we established two 100-m transects perpendicular to the road centre line, within which we sampled three macroplots of an area 400 m<sup>2</sup>. In each macroplot, nine quadrant microplots 2 × 2 m in size were set up for regenerated tree species and herbaceous plant survey. Chemical and physical parameters of soil were measured in laboratory. Results indicated that thirty-six herbaceous species and 13 regenerated tree species were recorded within the area of 100 m from the road verge. At the different distances from the road verge and both down and up-slope, the ground cover of Carex sylvatica and Rubus caesius L. as well as regeneration density of Carpinus betulus L. were higher compared to other species. Menhenick, Margalef, Shannon and Simpson indices were higher at the distance of 0–20 m than at the distances of 40–60 m and 80–100 m. Camargo and Smith-Wilson indices decreased when increasing distance to the road. These results are expected to provide critical information for decision makers and land managers for managing plant species and maintaining the integrity of biological communities.  

Geringe Samenbank von beweidbaren Arten für die Etablierung von Waldweiden im Schweizer Mittelland

Kipfer T. and Bosshard A. 2007. Low seed bank of herb species suitable for grazing hampers the establishment of wood pastures in the Swiss lowlands. Bot. Helv. 117: 159 – 167. Controlled forest grazing is expected to yield benefits for biodiversity conservation, landscape quality, and in some cases also for land use economy. In the Swiss lowlands, first attempts are being made to reintroduce forest grazing in productive beech forests, but methodic experience is still limited. One main issue concerns the development of the vegetation after forest stands have been thinned to improve light conditions: Will grassland vegetation establish spontaneously? The present study analyses the composition of the soil seed bank of four beech forest stands. The seed bank density ranged from 1’244 to 28’651 seeds m−2. Seed banks mainly consisted of forest and ruderal species; most abundant were Juncus effusus, Carex sylvatica, Rubus spp. and Clematis vitalba. Seeds of grassland plants were restricted to a few species, and their abundance in the seed bank decreased rapidly with increasing distance from the forest edge. These results reveal that there is little potential for grasslands to develop spontaneously from the seed bank. The introduction of grassland species of local origin using the green hay method is therefore recommended to prevent soil degradation during the first years of grazing, to fulfil minimal biodiversity requirements and to lower the risk of an establishment of neophytes and other problematic plant species.

Tolerance of understory plants subject to herbivory by roe deer

Current understanding of plant–herbivore interactions postulates that forest understory species are less tolerant to herbivory by large mammals than grassland species. As yet, research on forest species has focused on extensive biomass loss. However, forest dwelling ungulates are often selective browsers, hence biomass loss experienced by forage species is mostly limited to specific plant modules. We investigated the impact of herbivory on common forage species of roe deer Capreolus capreolus by simulating browsing on wild transplants of the two herbs Geum urbanum and Prenanthes purpurea, and the two graminoids Carex sylvatica and Luzula luzuloides. Two clipping regimes simulated different browsing frequencies, whereas shading and full day light represented light conditions in closed forests and gaps, respectively. Single clipping did not affect above ground biomass production of any species, independent of light conditions. Repeated biomass loss led to undercompensation in L. luzuloides, marginal compensation in C. sylvatica, and full compensation in G. urbanum and P. purpurea measured as above ground biomass production. The change in root biomass after clipping was positively correlated with the change in above ground biomass production in all four species. In contrast, nitrogen concentration was negatively correlated with above ground biomass in the graminoids, whereas no relationship between nitrogen and biomass was found in the herbs. Although light conditions and plant provenance affected biomass production, we found no effect of light conditions on plant reactions to herbivory. These results suggest that forest understory species, graminoids as well as herbs, are tolerant to herbivory by selective browsers such as roe deer. As in grassland ecosystems, the degree of compensatory growth depends on amount and frequency of biomass loss.

Forest fragmentation and plant reproductive success: a case study in four perennial herbs

We assessed the effects of habitat fragmentation on reproductive success in natural populations of four forest herbs with differing life-history traits and whose distribution patterns appeared to be negatively affected by decreased habitat size and/or increased isolation: Carex sylvatica, Galium odoratum, Sanicula europaea and Veronica montana. Our aims were to test (1) whether habitat size and isolation are positively correlated with population size and isolation, respectively, (2) whether plant reproductive success, a major component of plant fitness, is reduced in small and/or isolated populations when also accounting for differences in habitat quality (edaphic conditions, light intensity) and the effects of plant size, and (3) whether species with different life histories are affected differently. There were significant positive relationships between habitat and population size and between habitat and population isolation in some, but not all of the species. We mostly found no negative effects of small population size or isolation on reproduction. However, reproductive success was reduced in small populations of Sanicula, and this effect was independent of differences in plant size and environmental conditions. The reduced fecundity in small populations may be a consequence of the Allee-effect, a possible mechanism being pollen limitation. Furthermore, the proportion of flowering ramets was reduced in small and isolated populations of Galium, which may have been caused by changes in population structure. Lastly, we found some evidence for largely outcrossing, non-clonal species to be more sensitive to reductions in population size, at least in terms of their reproductive success.

Genetic Structure in Populations of an Ancient Woodland Sedge, Carex sylvatica Hudson, at a Regional and Local Scale

Wood sedge (Carex sylvatica) is a well-known ancient woodland species with a long-term persistent seed bank and a caespitose growth habit. All thirteen isolated Carex sylvatica populations in the Dutch Rhine floodplain (including the river branches Waal and IJssel) were mapped in detail and analysed for genetic variation at a large number of AFLP loci and one microsatellite locus. Across all populations, only 40 % of the sampled individuals (n=216) represented a unique genotype. A high number of the studied patches (spatial clusters of tussocks, 2-10 m in diameter) within populations contained only one or a few genotypes. Identical plants (tussocks) were also found 20-500 m apart and in one case even 1000 m apart. Observed heterozygosity levels (H(O)=0.029) were low, indicating low levels of gene flow, which is in agreement with the selfing nature of other caespitose sedges. Although the number of genotypes in populations is low, these genotypes are genetically very distinct and variation within populations accounted for 55% of the total variation. The absence of a correlation between genetic and geographic distances among populations, and the scattered distribution of genotypes among patches within woodlands, support our hypothesis of rare establishments and subsequent local dispersal within woodlands in this forest floor species, which may benefit from and partly depend on human land use and forest management activities.

Glechoma hederaceaL. (Nepeta glechomaBenth.,N. hederacea(L.) Trev.)

A polycarpic, aromatic, often purplish, softly hairy or nearly glabrous perennial herb. Flowering shoots 10–30 (–60) cm long, square in section and ascending or erect. Non-flowering stems also square in section, creeping and rooting at many, but not all, nodes. Leaf laminae 4–35 (–80) × 6–40 (–80) mm, reniform to ovate–cordate, obtuse or subacute and coarsely crenate. Petioles highly variable in length from 10 mm in grassland to over 200 mm in woodland with dense canopy cover and dense ground vegetation. Bracteoles 1–1.5 mm, shortly hispid or pubescent. Flowers zygomorphic and hypogynous, borne in few (2–5)-flowered secund axillary whorls, the bracts not differing from the foliage leaves. Calyx tubular or tubular-campanulate, 15-veined, not gibbous at base, and somewhat two-lipped. Upper lip of the corolla flat with three triangular acuminate teeth that are 0.2–0.3 times as long as the tube. Lower lip with two teeth. Corolla tube narrowly obconical, straight and hairy within at the base of lower lip. Corolla (6–) 15–22 (–25) mm, usually blue–violet with purple spots on the lower lip; rarely pink or white. Stamens four, two long and two short, borne on corolla tube and lying below upper lip; anther cells at right angles to each other, each opening by a separate slit. Ovary four-celled and deeply four-lobed, each cell with one ovule. Style gynobasic, its branches equal. Hermaphrodite and male-sterile forms of flowers occur, the latter usually with smaller corollas than hermaphrodite flowers, and much-reduced, pollen-less stamens that are often included in the corolla tube. Clones usually bear either only hermaphrodite or only male-sterile flowers, but in rare cases both types are found on the same individual (Price 1991). Each flower produces a maximum of four obovoid, slightly angled, smooth nutlets with a mean air-dry mass of 0.69 mg (n = 100). Each is slightly angled owing to pressure exerted by the adjacent developing nutlets before dispersal, and each bears a grey protuberance which may be an elaiosome. The dimensions of the seed are 1.9 × 1.1 mm. Glechoma serbica Halacsy & Wettst., which has been recorded in former Jugoslavia, is probably an ecological modification of G. hederacea (Fl. Eur. 3). The southern counterpart of G. hederacea in Europe is ssp. hirsuta (Waldst. & Kit.) F. Hermann, sometimes referred to as G. hirsuta (Elias 1979, 1983). This has denser and longer hairs and longer calyx teeth than G. hederacea, and the corolla is pale blue. It has been recorded in Albania, Austria, Bulgaria, the Czech Republic, Greece, Hungary, Italy, former Jugoslavia, Poland, Rumania, central and south-west Russia, Sardinia and Sicily (Fl. Eur. 3). Intermediates, which are presumably hybrids between G. hederacea and G. hirsuta, sometimes occur (Fl. Eur. 3). In eastern Asia a more or less distinct, short-pubescent race occurs that is called ssp. grandis (A. Gray) Hara [also var. grandis A. Gray and var. longituba (Nakai) Kuprian] (Hulten 1971). In North America the variety micrantha Moricand [or var. parviflora (Benth.) House] is distinguished (Hulten 1971).

A study of species richness and diversity in seed banks and its use for the environmental mitigation of a proposed holiday village development in a coniferized woodland in south east England

A survey was carried out to determine the density and species composition of germinable seed in the surface soil layers of 30 plots within a coniferized lowland woodland in East Kent in order to establish the resources available for habitat creation in the event of some areas being modified during a proposed holiday village development. The selected plots included conifer plantations (up to 69 years old), broad-leaved plantations and the semi-natural broad-leaved edges that remain on parts of the perimeter of the site which were used as the control. A total of 13 682 seedlings emerged from the soil samples during the four-month germination trials. Fifty-two species were identified of which eight were ancient woodland indicator species for south-east England. The most abundant species represented in the seed banks were: Juncus effusus, Rubus fruticosus, Carex sylvatica, Betula pendula and Agrostis tenuis. Between-site comparisons of coniferous plots of different ages revealed a marked reduction in the seed species and seed density in plantations over 65 years old. Results of soil nutrient and texture analyses ruled out the likelihood of edaphic factors being responsible for between-site differences in seed bank composition. Seed species richness and diversity (Shannon-Wiener diversity index) were greatest in the semi-natural broad-leaved edges, but the diversity index used also showed that two replanted conifer sites had high values despite few species being present. The usefulness and limitations of diversity indices in the context of seed bank studies is discussed. From the results of the study, management proposals for the site have been put forward in order to maintain floristic diversity and mitigate the impact of the proposed development.

Influence of NO3 - and NH4 + nutrition on fermentation, nitrate reductase activity and adenylate energy charge of roots of Carex pseudocyperus L. and Carex sylvatica Huds. exposed to anaerobic nutrient solutions

The adenylate energy charge, production of ethanol and lactate, and nitrate reductase activity were determined in order to study the influence of different nitrogen sources on the metabolic responses of roots of Carex pseudocyperus L. and Carex sylvatica HUDS. exposed to anaerobic nutrient solutions. Determination of adenylates was carried out by means of a modified HPLC technique. Total quantity of adenylates was higher in Carex pseudocyperus than in Carex sylvatica under all conditions. In contrast, the adenylate energy charge was only slightly different between the species and decreased more or less in relation to the applied nitrogen source under oxygen deficiency. The adenylate energy charge in roots of plants under nitrate nutrition showed a smaller decrease under anaerobic environmental conditions than plants grown with ammonium or nitrate/ammonium. Roots of nitrate-fed plants showed a lower ethanol and lactate production than ammonium/nitrate- and ammonium-fed plants. Ethanol production was higher in C. pseudocyperus, formation of lactate was lower compared to that in Carex sylvatica. The activity of enzymes involved in fermentation processes (ADH, LDH and PDC) was enhanced significantly after 24 hours of exposure to anaerobic nutrient solutions in roots of both species. The induction of these enzymes was only slightly influenced by different nitrogen supply. In vivo nitrate reductase activity increased almost 3-fold compared to the aerobic treatment in both species and overcompensated loss of NADH reoxidation capacity caused by decrease of ethanol and lactate development. Induction of in vitro nitrate reductase activity was enhanced 313% in C. pseudocyperus and 349% in C. sylvatica under anaerobic environmental conditions and nitrate supply. These results indicate that nitrate may serve as an alternative electron acceptor in anaerobic plant root metabolism and that the nitrate-supported energy charge may be due to an accelerated glycolytic flux resulting from a more effective NADH reoxidation capacity by nitrate reduction plus fermentation than by fermentation alone.

Importance of ammonium and nitrate to the performance of herb-layer species from deciduous forests in Southern Sweden

Experiments were performed on the effect on growth and uptake of nitrogen given as NH 4 and/or NO 3 in a nutrient solution (pH 4.2) of a composition similar to that of the rhizosphere soil solution of an acidic beech forest but lacking Al. Seven treatments (0.2 and 0.4 mM NH 4 and NO 3, respectively, and 0.1 + 0.1, 0.2 + 0.2, 0.4 + 0.4 mM of NH 4 + NO 3) were used in a flowing solution culture without recirculation. The seven species tested have ecological distributions which range from very acid soils with low nutrient levels and nitrogen mainly present as NH 4, to less acidic and nitrifying soils. In the solution experiment, species occurring in very acidic soils had small preferences for nitrogen form or combination ( Deschampsia flexuosa, Carex pilulifera, Milium effusum), while Aegopodium podagraria of less acidic soils preferred NO 3. The other three species, Poa nemoralis, Bromus benekenii and Carex sylvatica, grew best in a mixed solution. Results of a short-term (2–24 hr) exposure experiment showed that all species had a higher nitrogen uptake from NH 4 in the solo and mixed solutions. Total N uptake was, however, similar for the solo NH 4 and mixed solutions for all species except D. flexuosa and C. pilulifera, which had the highest N uptake with solo NH 4. It was concluded that none of the species studied grew best when NH 4 was supplied as the sole N source. This may restrict the distribution of species in very acid soils, where nitrification may be lacking.