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As part of an ongoing taxonomic study of the genus Deyeuxia, typifications for 12 names belonging to subtribe Agrostidinae from South America are presented here. A neotype for Bromidium rigescens var. brevifolium is herein designated. Eleven names belonging to the genera Agrostis, Calamagrostis, and Deyeuxia are lectotypified. Epitypes for Calamagrostis heterophylla var. robustior and Deyeuxia velutina are designated. [ABSTRACT FROM AUTHOR]

Fungi of genus Epichloë (Ascomycota, Clavicipitaceae) are common endophytic symbionts of Poaceae, including wild and agronomically important cool-season grass species (subfam. Poöideae). Here, we examined the genetic diversity of Epichloë from three European species of Brachypodium (B. sylvaticum, B. pinnatum and B. phoenicoides) and three species of Calamagrostis (C. arundinacea, C. purpurea and C. villosa), using DNA sequences of tubB and tefA genes. In addition, microsatellite markers were obtained from a larger set of isolates from B. sylvaticum sampled across Europe. Based on phylogenetic analyses the isolates from Brachypodium hosts were placed in three different subclades within the Epichloë typhina complex (ETC) but did not strictly group according to host grass species, suggesting that the host does not always select for particular endophyte genotypes. Analysis of microsatellite markers confirmed the presence of genetically distinct lineages of Epichloësylvatica on B. sylvaticum, which appeared to be tied to different modes of reproduction (sexual or asexual). Among isolates from Calamagrostis hosts, two subclades were detected which were placed outside ETC. These endophyte lineages are recognized as distinct species for which we propose the names E. calamagrostidis Leuchtm. & Schardl, sp. nov. and E. ftanensis Leuchtm. & A.D. Treindl, sp. nov. This study extends knowledge of the phylogeny and evolutionary diversification of Epichloë endophytes that are symbionts of wild Brachypodium and Calamagrostis host grasses. [ABSTRACT FROM AUTHOR]

To investigate the evolutionary relationships and biogeographical history among the species of Calamagrostis and other members of subtribes Agrostidinae, Calothecinae, Echinopogoninae, and Paramochloinae, we generated a phylogeny based on DNA sequences from one nuclear ribosomal (ITS) and three plastid regions (rpl32‐trnL spacer, rps16‐trnK spacer, and rps16 intron). Based on our phylogeny, we identified seven species groups (clades) within Calamagrostis: the Meridionalis group comprises two species from Central and South America, the Americana group comprises species from North America, the Deyeuxia and Epigeios groups comprise species from Eurasia, the Orientalis group comprises species from East Asia, the Purpurea group comprises species from Eurasia and North America, and the Calamagrostis group comprises species from Eurasia and North America. We hypothesize that Calamagrostis originated in North America with the primary split of the Meridionalis group, followed by split between the autochthonous Americana group and two future Eurasian branches encompassing all the remaining groups, which possibly dispersed into Eurasia independently. The molecular data suggest that hybridization and genomic introgression played a prominent role in the evolutionary history of Calamagrostis. We propose a new genus, Condilorachia, segregated from Trisetum s.l., with three species from South America for which we propose new combinations: Condilorachia bulbosa, Condilorachia brasiliensis, and Condilorachia juergensii; a new combination in Greeneochloa, Greeneochloa expansa; and the subsumption of Dichelachne into Pentapogon with 20 new combinations: Pentapogon avenoides, Pentapogon brassii, Pentapogon chaseianus, Pentapogon crinita, Pentapogon densus, Pentapogon frigidus, Pentapogon gunnianus, Pentapogon hirtella, Pentapogon inaequiglumis, Pentapogon lautumia, Pentapogon micrantha, Pentapogon parva, Pentapogon quadrisetus, Pentapogon rara, Pentapogon robusta, Pentapogon scaberulus, Pentapogon sclerophyllus, Pentapogon suizanensis, Pentapogon sieberiana, and Pentapogon validus. We provide a diagnosis, description, and a key to the species of Condilorachia. [ABSTRACT FROM AUTHOR]

The floodplain of the rivers Danube, March/Morava and Thaya/Dyje in eastern Austria and western Slovakia harbours a great diversity of meadows, reed swamps and sedge-bed communities. However, the grasslands along the Danube have not been adequately addressed by any study up to now, and a transnational revision of the alluvial grasslands is completely lacking. In this third part of a series focusing on the syntaxonomy of the Pannonian grasslands of Austria, we present a detailed classification of the grassland and marsh vegetation of the Danube and March-Thaya floodplain. We compiled all available relevés from the study area belonging to the classes Phragmito-Magnocaricetea, Molinio-Arrhenatheretea and Festuco-Brometea. In total, our data set comprised 2119 relevés, of which 355 were from Slovakia. We conducted a TWINSPAN classification and, based on a provisional syntaxonomic interpretation of the clusters, assigned all relevés to classes, orders, alliances and associations using the total cover of the diagnostic species in each relevé as the assignment criterion. We identified 42 associations and five provisional communities belonging to 14 alliances. Our revision includes substantial changes to previous overviews, in particular regarding the alluvial grasslands of the March-Thaya floodplain. We merge Lathyro palustris-Gratioletum, Gratiolo-Caricetum suzae, Cnidio-Violetum pumilae, Serratulo-Plantaginetum altissimae and "Silaetum pratensis" into only two associations (Gratiolo-Caricetum suzae and Cnidio-Violetum pumilae, alliance Deschampsion), which are differentiated along the moisture gradient. The Ophioglosso-Caricetum tomentosae is revealed as a geographical vicariant of the Cnidio-Violetum pumilae, replacing the latter along the Danube. The Agropyro-Alopecuretum pratensis is newly reported for Austria. The mesic Festuca rupicola grasslands along the March/Morava (previously named "Serratulo-Festucetum commutatae") are included in the Colchico-Festucetum rupicolae (Cirsio-Brachypodion). Ranunculo bulbosi-Arrhenatheretum, Pastinaco-Arrhenatheretum, Festuco rupicolae-Brometum and Polygalo-Brachypodietum (the latter in a new subass. selaginelletosum helveticae) are confirmed as widespread grassland types in the Danube floodplain, and the Teucrio botryos-Andropogonetum (Festucion valesiacae) is split into two subassociations. Moreover, we report four grassland types dominated by Elymus repens and Calamagrostis epigejos, provisionally treated as rankless communities, which have been neglected by all previous authors. [ABSTRACT FROM AUTHOR]

We investigated the monophyly of Costularia (25 species), a genus of tribe Schoeneae (Cyperaceae) that illustrates a remarkable distribution pattern from southeastern Africa, over Madagascar, the Mascarenes and Seychelles, to Malesia and New Caledonia. A further species, Tetraria borneensis , has been suggested to belong to Costularia . Relationships and divergence times were inferred using an existing four marker phylogeny of Cyperaceae tribe Schoeneae expanded with newly generated sequence data mainly for Costularia s.l. species. Phylogenetic reconstruction was executed using Bayesian inference and maximum likelihood approaches. Divergence times were estimated using a relaxed molecular clock model, calibrated with fossil data. Based on our results, Tetraria borneensis is not related to the species of Costularia . Costularia s.l. is composed of four distinct evolutionary lineages. Two lineages, one including the type species, are part of the Oreobolus clade, i.e. a much reduced genus Costularia restricted to southeastern Africa, Madagascar, the Mascarenes and Seychelles, and a small endemic genus from New Caledonia for which a new genus Chamaedendron is erected based on Costularia subgenus Chamaedendron . The other two lineages are part of the Tricostularia clade, i.e. a separate single-species lineage from the Seychelles for which a new genus ( Xyroschoenus ) is described, and Costularia subgenus Lophoschoenus . For the latter, more research is needed to test whether they are congeneric with the species placed in the reticulate-sheathed Tetraria clade. [ABSTRACT FROM AUTHOR]

Poa laegaardiana sp. nov., is described and illustrated. The new species was found growing on sandy, volcanic soil in Festuca-Calamagrostis dominated grasslands southwest of Ambato and 2.2 km from Fecundo Vela in Provincia de Bolivar. The new species is morphologically similar to Poa gigantea but differs in having glumes 3/4 to 7/8 as long as the adjacent lemmas, a callus with a sparse, short, dorsal tuft of woolly hairs, culms 50-72 cm tall and spikelets 4.1-4.8 mm long. In addition, we include a key to the narrow-spikelike panicled species of Poa in Ecuador. [ABSTRACT FROM AUTHOR]

Deyeuxia angustifolia wetlands widely distribute in the Sanjiang Plain in the northeastern China. Owing to land reclamation, these D. angustifolia wetland ecosystems are rapidly shrinking on the landscape, threatening ecosystem functioning and regional ecological security. Converting farmlands to wetlands serves as an ecological engineering widely used for natural restoration in Sangjiang Plain. Vegetation restoration process of restored D. angustifolia wetlands needs to be fully assessed. However, limited information is available for uncovering the impact of restoration time on ecological vegetative characteristics under natural succession. In this study, vegetation survey and sampling were carried out in six restored D. angustifolia wetlands with a chronosequence (2-, 4-, 8-, 13-, 16-, 20-year restoration), as well as the undisturbed D. angustifolia wetland. Plant community composition changed greatly during the past two decades. In the 2-year and 4-year restored wetlands, farmland weeds Artemisia argyi and Calamagrostis brachytricha were the dominant species. Plant communities were gradually dominated by D. angustifolia and Carex spp. with the increase of restoration time. Species diversity in restored wetlands was higher than that in undisturbed wetland and decreased with restoration time increasing. Plant height and coverage increased with the increase of the restoration time, whereas the plant density generally decreased. The plant communities in restored wetlands were increasingly close to that in the undisturbed wetland. The forb, sedge and grass plants accumulated more biomass in 2-year, 8-year and 20-year restored wetlands, respectively. Regression between the grass biomass and species diversity is significantly negative ( p  ≤ 0.05). Results in this study suggest that the vegetation of cultivated D. angustifolia wetland could be restored effectively through natural succession, although there were some functional differences between restored and undisturbed D. angustifolia wetlands. Community composition variance and functional traits based on vital attributes can be used to reliably predict changes in diversity of species in response to natural restoration. [ABSTRACT FROM AUTHOR]

Geodiversity plays an important role in species establishment during spontaneous succession. At post-mining sites in the Czech Republic in 2003, we established plots in which the surface of the heaped overburden was either kept wave-like or leveled. Based on surveys conducted from 2006 to 2015, leveled plots were increasingly dominated by grasses and herbs (and especially by the grass Calamagrostis epigejos ) while the wave-like plots were increasingly dominated by the trees Salix caprea and Betula pendula . In 2015, a detailed survey was conducted of the dominant species. Both S. caprea and B. pendula occurred more often in wave-like plots than in leveled plots; this was particularly true for trees taller than 1 m, which were absent in leveled plots. In wave-like plots, leaf and root biomasses of both woody species were higher on the wave slopes than on the wave depressions. Nitrogen content was higher but content stress indicating proline in leaves of S. caprea was lower in wave-like plots than in leveled plots. In wave-like plots, both woody species occurred mainly on wave slopes but C. epigejos occurred mainly in the depressions. We speculate that trees were more abundant in wave-like plots than in leveled plots because the waves trapped tree seeds and snow and because the soil porosity was greater in wave-like than in leveled plots. Grasses may have preferred the leveled plots because soil porosity was lower and clay content was higher in leveled than in wave-like plots. [ABSTRACT FROM AUTHOR]

New taxonomic and distributional data are provided for three eastern Asian species of Calamagrostis (Poaceae, Agrostidinae) in Vietnam: C. abnormis (Hook. f.) Shukla, C. extremiorientalis (Tzvel.) Prob. and C. tripilifera Hook. f. The new national record of C. extremiorientalis is reported here for Vietnam, where it was previously misidentified as C. elatior (Griseb.) A. Camus or Deyeuxia petelotii Hitchc. (= C. abnormis). The presence of C. tripilifera and C. abnormis in Vietnam is confirmed. Additional new provincial records of C. extremiorientalis from Japan's Bonin Islands (also known as the Ogasawara Islands) and C. tripilifera from Daba Mountains in the northern Chongqing Municipality (Central China) are reported here. A key for identification of Calamagrostis species in Vietnam, nomenclatural data and information about geographical, altitudinal and habitat distributions are provided. Maps showing their complete distribution in eastern Asia are presented. [ABSTRACT FROM AUTHOR]

We examined nitrogen transport and wetland primary production along hydrologic flow paths that link nitrogen-fixing alder ( Alnus spp.) stands to downslope wetlands and streams in the Kenai Lowlands, Alaska. We expected that nitrate concentrations in surface water and groundwater would be higher on flow paths below alder. We further expected that nitrate concentrations would be higher in surface water and groundwater at the base of short flow paths with alder and that streamside wetlands at the base of alder-near flow paths would be less nitrogen limited than wetlands at the base of long flow paths with alder. Our results showed that groundwater nitrate-N concentrations were significantly higher at alder-near sites than at no-alder sites, but did not differ significantly between alder-far sites and no-alder sites or between alder-far sites and alder-near sites. A survey of 15N stable isotope signatures in soils and foliage in alder-near and no-alder flow paths indicated the alder-derived nitrogen evident in soils below alder is quickly integrated downslope. Additionally, there was a significant difference in the relative increase in plant biomass after nitrogen fertilization, with the greatest increase occurring in the no-alder sites. This study demonstrates that streamside wetlands and streams are connected to the surrounding landscapes through hydrologic flow paths, and flow paths with alder stands are potential 'hot spots' for nitrogen subsidies at the hillslope scale. [ABSTRACT FROM AUTHOR]

Context:Human beings have long utilized plants for medicinal purposes. Investigation of these plants has led to the discovery of several modern drugs. Objective:This paper documents and evaluates traditional knowledge on medicinal plants used by the local people of Mihalgazi district of Eskişehir, Turkey. Materials and methods:Six villages of the study area were visited between February 2014 and April 2015 to collect the data. One hundred and eighty-nine informants were interviewed by the survey method and face to face semi-structured interviews. Taxonomic identification, the most commonly used plant parts, preparation and administration methods were evaluated. Ethnomedicinal data were analyzed quantitatively with relative importance (RI) and the informant consensus factor (FIC). Results:This paper reported a total of 52 medicinal plants (37 wild, 15 cultivated) belonging to 34 families. Some uses of 22 plants were not found in the literature and are reported for the first time in this study. Furthermore, one of the plants,Calamagrostis arundinacea(L.) Roth (Poaceae), was reported for the first time as being used within the scope of traditional therapies. Discussion and conclusion:This study recorded traditional knowledge on medicinal plants used in Mihalgazi, Turkey. This paper provides a basis for further investigations to discover efficient pharmaceuticals. [ABSTRACT FROM AUTHOR]

Deyeuxia nyingchiensis is here recombined as Calamagrostis nyingchiensis comb. nov. as a result of recent studies of worldwide Agrostidinae. A new record of C. nyingchiensis is reported from Shangri-la (Zhongdian) County in Yunnan Province, SW China. Previously, C. nyingchiensis was noted from eastern Xizang and southern Sichuan, SW China. It is compared with the morphologically similar species C. scabrescens. A map with all known geographic records of C. nyingchiensis is presented. [ABSTRACT FROM AUTHOR]

There is ample evidence that methane (CH) emissions from natural wetlands exhibit large spatial variations at a field scale. However, little is known about the metabolically active methanogens mediating these differences. We explored the spatial patterns in active methanogens of summer inundated Calamagrostis angustifolia marsh with low CH emissions and permanently inundated Carex lasiocarpa marsh with high CH emissions in Sanjiang Plain, China. In C. angustifolia marsh, the addition of C-acetate significantly increased the CH production rate, and Methanosarcinaceae methanogens were found to participate in the consumption of acetate. In C. lasiocarpa marsh, there was no apparent increase in the CH production rate and no methanogen species were labeled with C. When CO-H was added, however, CH production was found to be due to Fen Cluster ( Methanomicrobiales) in C. angustifolia marsh and Methanobacterium Cluster B ( Methanobacteriaceae) together with Fen Cluster in C. lasiocarpa marsh. These results suggested that CH was produced primarily by hydrogenotrophic methanogens using substrates mainly derived from plant litter in C. lasiocarpa marsh and by both hydrogenotrophic and acetoclastic methanogens using substrates mainly derived from root exudate in C. angustifolia marsh. The significantly lower CH emissions measured in situ in C. angustifolia marsh was primarily due to a deficiency of substrates compared to C. lasiocarpa marsh. Therefore, we speculate that the substrate source regulates both the type of active methanogens and the CH production pathway and consequently contributes to the spatial variations in CH productions observed in these freshwater marshes. [ABSTRACT FROM AUTHOR]

As a result of recent studies of worldwide Agrostidinae, Deyeuxia gaoligongensis Paszko, D. himalaica Liou ex W. L. Chen and D. sorengii Paszko & W. L. Chen are here recombined as Calamagrostis gaoligongensis comb. nov., C. himalaica comb. nov. and C. sorengii comb. nov., respectively, and the first record of the Sino-Himalayan species C. himalaica from Yunnan Province, southwestern China, is reported. Calamagrostis himalaica occurs primarily in southeast Xizang, southwestern China, with a single locality recorded recently in Kachin State, Myanmar (Burma). A map with all known geographic records of C. himalaica and an image of the newly identified specimen are presented. [ABSTRACT FROM AUTHOR]

In 2005, a 7-ha artificial watershed (Chicken Creek) was built on a post mined landscape in Lusatia, Germany from sandy substrates of Pleistocene origin, commonly used in reclamation. The watershed was developed to investigate the initial phase of soil and ecosystem development under natural conditions. At this early stage, mineral nitrogen in young sandy soils is primarily limited and nitrogen fixing legumes become key components of natural succession. Local abundant pioneering legumes Lotus corniculatus and Trifolium arvense and one pioneer grass species Calamagrostis epigeios were investigated 5 years after watershed construction. In this study, we investigated the influence of spatial root and nodule distribution of these species on soil nitrogen accumulation. Soil, including roots, was sampled from field monoliths covered with the aforementioned plant species. Root systems of both legumes were mainly restricted to the upper 20 cm of soil, whereas roots of C. epigeios also developed strongly at greater depths. A positive relationship was found, with higher plant densities associated with higher root densities which were associated with higher nodule densities for legumes and which were all associated with significantly higher soil nitrogen content relative to non-vegetated areas. This research provides rare information on the role root systems of pioneer legumes play in soil nitrogen input in the early stage of soil and ecosystem development during revegetation by natural succession. [ABSTRACT FROM AUTHOR]

Post-mining restoration sites often develop novel ecosystems as soil conditions are completely new and ecosystem assemblage can be spontaneous even on afforested sites. This study presents results from long-term monitoring and evaluation of an afforested oil-shale quarry in Estonia. The study is based on chronosequence data of soil and vegetation and comparisons are made to similar forest site-types used in forest management in Estonia. After site reclamation, soil development lowered pH and increased N, K, and organic C content in soil to levels similar to the common Hepatica forest site-type but P, total C, and pH were more similar to the Calamagrostis forest site-type. Vegetation of the restoration area differed from that on common forest sites; forest stand development was similar to the Hepatica forest-type. A variety of species were present that are representive of dry and wet sites, as well as infertile and fertile sites. It appears that novel ecosystems may be developing on post-mining reclaimed land in Northeast Estonia and may require adaptations to typical forest management regimes that have been based on site-types. Monitoring and evaluation gives an opportunity to plan further management activities on these areas. [ABSTRACT FROM AUTHOR]

There are large temporal and spatial variations of methane (CH) emissions from natural wetlands. To understand temporal changes of CH production potential (MPP), soil samples were collected from a permanently inundated Carex lasiocarpa marsh and a summer inundated Calamagrostis angustifolia marsh over the period from June to October of 2011. MPP, dissolved organic carbon (DOC) concentration, abundance and community structure of methanogenic archaea were assessed. In the C. lasiocarpa marsh, DOC concentration, MPP and the methanogen population showed similar seasonal variations and maximal values in September. MPP and DOC in the C. angustifolia marsh exhibited seasonal variations and values peaked during August, while the methanogen population decreased with plant growth. Methanogen abundance correlated significantly ( P = 0.02) with DOC only for the C. lasiocarpa marsh. During the sampling period, the dominant methanogens were the Methanosaetaceae and Zoige cluster I (ZC-Ι) in the C. angustifolia marsh, and Methanomicrobiales and ZC-Ι in the C. lasiocarpa marsh. MPP correlated significantly ( P = 0.04) with DOC and methanogen population in the C. lasiocarpa marsh but only with DOC in the C. angustifolia marsh. Addition of C. lasiocarpa litter enhanced MPP more effectively than addition of C. angustifolia litter, indicating that temporal variation of substrates is controlled by litter deposition in the C. lasiocarpa marsh while living plant matter is more important in the C. angustifolia marsh. This study indicated that there was no apparent shift in the dominant types of methanogen during the growth season in the species-specific freshwater wetlands. Temporal variation of MPP is controlled by substrates and substrate-driven changes in the abundance of methanogenic archaea in the C. lasiocarpa marsh, while MPP depends only on substrate availability derived from root exudates or soil organic matter in the C. angustifolia marsh. [ABSTRACT FROM AUTHOR]

Lodgepole pine ( Pinus contorta var. latifolia) stands were sampled in central Yukon, Canada (61.5-64°N latitude), which represented the northernmost 9% of the tree's North American range. Within this area, lodgepole pine occupied only ˜ 2% of the landscape. This study determined: 1) what forest sociations occurred (i.e. structural dominance-types); 2) how plant growth form composition and richness differed from the central portion of the species' geographical range; and 3) if stands were biased towards occurring on more thermally favorable south-facing slopes. Five lodgepole pine sociations were recognized among 100 relevés: Rhododendron groenlandicum (Labrador tea); Cladonia arbuscula (green reindeer lichen); Calamagrostis purpurascens (purple reedgrass); Hylocomium splendens (stairstep moss) and Alnus viridis (green alder, n = 4 relevés). Rhododendron stands were proportionally more common on low gradient sites and had more total plant cover than the other sociations. Cladonia and Calamagrostis stands were typically associated with dry coarse-textured soils and warm dry sites, respectively; whereas the composition of the Hylocomium sociation reflected the detrimental influences of atypically dense forest canopies on understory vascular plants. Only the Calamagrostis sociation was unique to the study region. Species richness among common northern lodgepole pine sociations averaged 16-19 taxa per relevé (p > 0.05). Northern compared to central range (n = 1394) relevés were compositionally different based on little overlap of their datasets in the ordination space. Northern vegetation had less (p < 0.001) total plant (129% vs 184%), deciduous shrub (9% vs 26%), broad-leaved herb (5% vs 25%), and bryophyte (27% vs 54%) cover; had greater macro-lichen cover (13% vs 5%) and lower floristic richness (11 vs 24 taxa) and was less than half as phytosociological diverse. Lodgepole pine stands in the northernmost portion of their range were not biased towards occurring on south-facing slopes, which suggested an ecological potential for range expansion. [ABSTRACT FROM AUTHOR]

Background: The Three Gorges project has caused many ecosystem problems. Ecological restoration using readily-available plants is an effective way of mitigating environmental impacts. Two perennial submergence-tolerant ecotypes of Calamagrostis arundinacea were planted in an experimental field in the drawdown zone. Responses of the two plant ecotypes to flooding stress in the drawdown zone were unknown. Methodology/Principal Findings: Carbohydrate content and membrane stability, two key factors for survival of plants under flooding stress, of two ecotypes (designated “dwarf” and “green”) of C. arundinacea growing at different elevations of the drawdown zone were investigated. Live stems (LS) and dead stems (DS) of the two plant ecotypes at eight elevations (175, 170, 162, 160, 158, 155, 152 m and 149 m) were sampled. Contents of soluble sugar, starch and malondialdehyde (MDA), as well as plasma membrane permeability of live stems were measured. The lowest elevations for survival of dwarf and green C. arundinacea were 160 m and 158 m, respectively. Soluble sugar content of live stems of both ecotypes decreased with elevation, with amounts from an elevation of 170 m being lower than from an elevation of 175 m. MDA content and plasma membrane permeability in live stems of green C. arundinacea did not increase with the decrease in elevation, while these measures in dwarf C. arundinacea from an elevation of 162 m were significantly higher than from an elevation of 175 m. Conclusions: Carbohydrate content, especially soluble sugar content, in both ecotypes was more sensitive to flooding stress than membrane stability. Green C. arundinacea had a higher tolerance to submergence than dwarf C. arundinacea, and thus green C. arundinacea can be planted at lower elevations than dwarf C. arundinacea. [ABSTRACT FROM AUTHOR]

Highlights: [•] Species richness/seedling emergence decreased significantly with sediment addition. [•] Native species disappeared from sediment disturbed wetland. [•] Plant species responded differently to the addition of sediment. [•] Knowledge gained from this study will provide insight into irrigation management. [ABSTRACT FROM AUTHOR]

For the District of Lircay, we report a total of 46 species and one subspecies of the Poaceae family, grouped into 21genera, 11 tribes and 6 subfamilies. The genus Calamagrostis is the most diverse with 9 species, followed by Poa with 5 species. Also, Aciachne acicularis "paccupaccu", Arundo donax "carrizo", Cortaderia hieronymi and Ortachne erectifolia "iruichu" are new reports for the region of Huancavelica. Moreover, dichotomous keys are presented for the determination of species in the case a genus has more than one species. For each species, data on habitat, distribution, examined material and common name are included. [ABSTRACT FROM AUTHOR]

The effects of nitrogen deposition (N-deposition) on the carbon dynamics in typical Calamagrostis angustifolia wetland of Sanjiang Plain were studied by a pot-culture experiment during two continuous plant growing seasons. Elevated atmospheric N-deposition caused significant increases in the aboveground net primary production and root biomass; moreover, a preferential partition of carbon to root was also observed. Different soil carbon fractions gained due to elevated N-deposition and their response intensities followed the sequence of labile carbon > dissolved organic carbon > microbial biomass carbon, and the interaction between N-deposition and flooded condition facilitated the release of different carbon fractions. Positive correlations were found between CO2 and CH4 fluxes and liable carbon contents with N-deposition, and flooded condition also tended to facilitate CH4 fluxes and to inhibit the CO2 fluxes with N-deposition. The increases in soil carbon fractions occurring in the nitrogen treatments were significantly correlated with increases in root, aboveground parts, total biomass, and their carbon uptake. Our results suggested that N-deposition could enhance the contents of active carbon fractions in soil system and carbon accumulation in plant of the freshwater wetlands. [ABSTRACT FROM AUTHOR]

Sedge meadows can be difficult to restore from farmed fields if key structural dominants are missing from propagule banks. In hand-cultivated soybean fields in northeastern China, we asked if tussock-forming Carex and other wetland species were present as seed or asexual propagules. In the Sanjiang Plain, China, we compared the seed banks, vegetative propagules (below-ground) and standing vegetation of natural and restored sedge meadows, and hand-cultivated soybean fields in drained and flooded conditions. We found that important wetland species survived cultivation as seeds for some time (e.g. Calamogrostis angustifolia and Potamogeton crispus) and as field weeds (e.g. C. angustifolia and Phragmites australis). Key structural species were missing in these fields, for example, Carex meyeriana. We also observed that sedge meadows restored without planting or seeding lacked tussock-forming sedges. The structure of the seed bank was related to experimental water regime, and field environments of tussock height, thatch depth, and presence of burning as based on Nonmetric Multidimensional Scaling analysis. To re-establish the structure imposed by tussock sedges, specific technologies might be developed to encourage the development of tussocks in restored sedge meadows. [ABSTRACT FROM AUTHOR]

Question Diversification of grassland management is recommended as a tool for conservation of different taxonomic groups living in those habitats. How resistant and resilient are species-rich grasslands in terms of plant species richness and vegetation composition to short-term, small-scale perturbations caused by changes in management practice? Location Bílé Karpaty Mountains, SE Czech Republic. Methods The experiment included the effect of six management regimes (mowing in June; mowing in September; mowing in June and September; mowing in June and high stubble left; no management; mowing in June and mulching). It was conducted in species-rich wooded grasslands in the White Carpathians Mts., Czech Republic, represented by three types of plant community: a Bromus erectus community (with high species richness and low productivity), a Molinia arundinacea community (with high species richness and high productivity), and a Calamagrostis epigejos community (with low species richness and high productivity). After 3 yr, resistance was assessed, and traditional management (mowing once each year in June) was resumed; resilience was evaluated after three more years. Results While the species-rich, unproductive Bromus community was relatively resistant to less intensive management in terms of species richness, and therefore its resilience could not be assessed, it changed substantially in terms of vegetation composition (maximum dissimilarity between control and abandoned plots was 63%). The more productive Molinia and Calamagrostis communities lost up to 37% of species due to abandonment, but not as a consequence of other changes management regimes. After the traditional management was resumed, resilience was higher in the Calamagrostis community than in the Molinia community. Vegetation composition was not affected by treatments. Conclusions The results show that short-term abandonment causes loss of plant diversity in productive grasslands but not in less productive, species-rich grasslands in the short term. Other relaxed management regimes (e.g. high stubble and delayed mowing) were comparable with the control and can be used for a short time to increase diversity of management without an effect on plant species richness. However, further research is needed to assess the effects of these management practices when they are applied repeatedly or over the long term. [ABSTRACT FROM AUTHOR]

DewaxedCalamagrostis angustifoliaKom was pretreated with hot water at 60 and 90°C for 3 h, and then the residue obtained was successively treated with 70% ethanol, and 70% ethanol containing 0.2%, 1.0%, 2.0%, 4.0%, and 8.0% NaOH at 80°C for 3 h. The dissolved components were subjected to further separation to get eight lignin fractions, which were characterized by gel permeation chromatography, Fourier transform infrared, and sugar analysis. All the lignin fractions had small weight-average molecular weights between 810 and 2580 g/mol. Two typical lignins, L3(prepared with 70% ethanol) and L5(prepared with 70% ethanol containing 1.0% NaOH), were further analyzed using1H,13C NMR and HSQC spectroscopy. Signals from guaiacyl (G), syringyl (S), andp-hydroxyphenyl (H) units observed in aromatic/olefinic region of HSQC spectra indicated that the lignin fromCalamagrostis angustifoliaKom could be classified as “GSH” lignin. In aliphatic-oxygenated region, β-O-4′ together with small amounts of β-5′, β-β′, andp-hydroxycinnamyl alcohol end group were the main interunit linkages observed. Aqueous ethanol, which could avoid the cleavage of ether bonds in lignin at neutral condition, was more effective than water on lignin extraction. [ABSTRACT FROM AUTHOR]

Abstract: A matrix model for age-stage-structured population dynamics of Calamagrostis canescens, a perennial grass species colonizing forest clear-cut areas, was calibrated before from a type of data called ‘identified individuals with unknown parents’ (Logofet, 2008) in order to estimate λ 1, the dominant eigenvalue of the projection matrix. A number of methods were applied to tackle the ‘reproductive uncertainty’ in data, and the output variety contained λ 1 both greater and less than 1 (Logofet, 2008), leaving the estimation uncertain. An ‘adaptation conjecture’ was then proposed that reduced the calibration to a nonlinear constraint maximization problem and provided for a satisfactory outcome. Two reasons have now caused revisiting. First, the maximization technique has been theoretically comprehended. In particular, an existence-uniqueness theorem has been proved that requires the maximizing solution to be reached at a vertex of the polyhedral of constrains. To facilitate searching for the solution in practice, I use the notion of potential-growth indicator and prove R 0 and R 1, the known indicators, to be certain linear functions of the uncertain fertility rates in a general class of projection matrix patterns. To solve a conjugate linear maximization problem under the same constraints as for λ 1 is both theoretically and technically simpler, and this causes a practical benefit from the indication along with calculation. Second, the former uniform (non-specific) estimate of the upper bounds for the status-specific fertility rates has now conceded to the age-stage-specific estimates inferred from a special case study. These more sophisticated constraints produce respectively more accurate calibration, hence a more reliable estimation of λ 1 as the growth potential inherent in the population in a certain environment at a given time. [Copyright &y& Elsevier]

Abstract: The radioecological state of the forest ecosystem in the vicinity of the Ignalina Power Plant prior to decommissioning was analysed with specific emphasis on 137Cs and 90Sr activity concentrations in plant species growing in two reference sampling sites (Tilze and Grikiniskes). In the period of 1996–2008 the mean contamination of plants with 137Cs was from 45 to 119 Bq/kg and with 90Sr – from 3 to 42 Bq/kg. Measured 137Cs TF values for soil-root transfer mainly ranged between 1.0–1.4, except for Calamagrostis arundinacea which had a TF value of 0.1. On average, the 137Cs TF value from root to shoot was 1.7 fold higher than for soil to root transfer. 90Sr TF values (soil-root) were in the range of 1.2–1.8 but for Calluna vulgaris it was 0.2. The mean root to shoot TF value for 90Sr was 7.7 fold higher. These results indicate the higher 90Sr bioavailability than that of 137Cs in the forested area. The Grikiniskes reference site is located nearby the Ignalina NPP, specifically the heated water outlet channel, which results in altered microclimatic conditions. These specific microclimatic conditions result in relationships between 137Cs TF (soil-root) values and pH, moisture and organic matter content in the soil at Grikiniskes which appear to be different to those at the Tilze reference sampling site. [Copyright &y& Elsevier]

UV-B radiation and elevated CO2 may impact rhizosphere processes through altered below-ground plant resource allocation and root exudation, changes that may have implications for nutrient acquisition. As nutrients limit plant growth in many habitats, their supply may dictate plant response under elevated CO2. This study investigated UV-B exposure and elevated CO2 effects, including interactions, on plant growth, tissue chemistry and rooting responses relating to P acquisition. The sub-arctic grass Calamagrostis purpurea was subjected to UV-B (0 or 3.04 kJ m−2day−1) and CO2 (ambient 380 or 650 ppmv) treatments in a factorial glasshouse experiment, with sparingly soluble P (0 or 0.152 mg P per plant as FePO4) a further factor. It was hypothesized that UV-B exposure and elevated CO2 would change plant resource allocation, with CO2 mitigating adverse responses to UV-B exposure and aiding P uptake. Plant biomass and morphology, tissue composition and rhizosphere leachate properties were measured. UV-B directly affected chemical composition of shoots and interacted with CO2 to give a greater root biomass. Elevated CO2 altered the composition of both shoots and roots and increased shoot biomass and secondary root length, while leachate pH decreased. Below-ground responses to CO2 did not affect P acquisition although P limitation progressively reduced leachate pH and increased secondary root length. Although direct plant growth, foliar composition and below-ground nutrient acquisition responses were dominated by CO2 treatments, UV-B modified these CO2 responses significantly. These interactions have implications for plant responses to future atmospheric conditions. [ABSTRACT FROM AUTHOR]

Abstract: Wetland ecosystems store a large amount of organic carbon (C) in soils, due to the slow decomposition rates of plant litter and soil organic matter. Increased nitrogen (N) availability induced by human activities and global warming may accelerate litter decomposition and affect soil organic C dynamics in wetlands. In the present study, we investigated the effect of N addition on decomposition of Calamagrostis angustifolia litters from freshwater marshes in the Sanjiang Plain of Northeast China under field and laboratory conditions. First, we assessed the changes in initial litter chemical composition and subsequent decomposition following three years of N addition at the rate of 24gNm−2 year−1 under field conditions. Our results showed that N addition increased litter N concentration and decreased C/N ratio, and thus stimulated litter decomposition. Secondly, we examined the effect of increased N availability (0, 25, 50 and 100mgNg−1 litter) on litter decomposition under laboratory conditions. Increased exterior N availability also enhanced microbial respiration and increased litter mass loss under both waterlogging and non-waterlogging conditions. In addition, waterlogging conditions inhibited microbial respiration and suppressed litter mass loss. These findings demonstrated that N addition increased litter decomposition rates through improved litter quality and enhanced microbial activity in freshwater marshes of Northeast China. This implies that increased N availability accelerates litter decomposition rates, and thus may cause substantial losses of soil C and diminish and even reverse the C sink function of wetlands in the Sanjiang Plain of Northeast China. [Copyright &y& Elsevier]

Abstract: Iron cycling in wetlands is important because it plays an important role in interactions among wetland soils/sediments, plants and microorganisms. The seasonal variation of iron (Fe) distributed in two freshwater peatland ecosystems dominated by Calamagrostis angustifolia (CA) and Carex lasiocarpa (CL), was observed in Sanjiang Plain of Northeast China. The compartmentalization of the Fe cycle including storage in the atmosphere, litter, soil, and above- and below ground plant material was determined. The results showed that the Fe input from rain was 0.06gm−2 a−1, and the total Fe mass in the peatland ecosystem was 5.18×103 for CA and 1.40×103 gm−2 for CL. The major Fe pools were soils (98.6% and 97.1% for CA and CL, respectively). The Fe fluxes between each compartment resulted in the increase of the belowground Fe pool and decrease of the litter Fe pool currently both for CA and CL. CL has greater uptake coefficient (0.024) and cycle coefficient (0.034), but smaller use coefficient (0.58) than that of CA (0.02, 0.006, and 0.77, respectively). Peatland conversion for agriculture affected the former natural Fe cycle processes and mass balance to a certain extent in long term, because the Fe assimilated by soybean and rice are less than that of CA and CL, and cannot return to soils from harvesting. Drainage and ditch excavation for agricultural conversion caused considerable Fe loss via aqueous movement, so that Fe was likely lost and transported downstream by these ditch networks. [Copyright &y& Elsevier]

Regeneration of seminatural grasslands are often threatened by the invasion of Calamagrostis epigejos, which can slow down or arrest secondary succession. Here we report the results of a 9-year mowing experiment designed to suppress the spread of C. epigejos in mid-successional grasslands in Hungary. The experimental design consisted of 16 permanent plots of 3 × 3 m. Half of the plots were mowed twice a year (in June and September), the other half was left as control. Vegetation was sampled in 2 × 2 m quadrates before mowing in each year between 2001 and 2009. The effects of mowing were tested using repeated-measure analyses of variance (ANOVA) and Tukey HSD for post hoc tests. Significant decrease of C. epigejos appeared after 2 years of mowing. Species richness increased after 4 years, while diversity after 8 years. By this time the target native species Brachypodium pinnatum become dominant. Similar trends appeared in the control plots during spontaneous succession but at much slower rates. Our results suggest that C. epigejos disappears spontaneously in secondary grassland succession after ca. 40-50 years. However, mowing twice a year can speed up this process by opening a 'colonization window' to the valuable target species. For successful control, mowing should be maintained for approximately 8 years. [ABSTRACT FROM AUTHOR]

Principal component analysis of specimen measurements revealed morphological variation within Chinese Calamagrostis epigeios correlated with differences in geographical distribution. We conducted a morphological examination of specimens from the range of the species, with the goal of developing a treatment for its Chinese members reflecting the global diversity complex. The confusing taxonomy of this complex is clarified with the recognition of three species in China, namely C. epigeios, C. extremiorientalis, and C. macrolepis. Calamagrostis epigeios is an exclusively temperate grass occurring in the northwestern, northern, and northeastern parts of China. It has spikelets 4-7 mm long, glumes equal or subequal, awn arising near the middle of the lemma back, upper leaf surface smooth and with shallow ribs and furrows. Calamagrostis extremiorientalis is a tropical and subtropical grass that occurs in the southwest provinces of China (except Xizang) throughout south central provinces and east to the northeastern parts of China. It is morphologically similar to C. epigeios. However, C. extremiorientalis has the awn arising from the upper one-third of the lemma back, upper leaf surface scabrid because of the presence of short stiff hairs, and with tall ribs and deep furrows. Calamagrostis macrolepis occurs in the northwestern, northern, and northeastern parts of China. It has a robust habit, spikelets 6.5-11 mm long, and glumes unequal, the upper 1-1.5 mm shorter than the lower. New synonyms, descriptions, and citations of representative specimens are provided for each species, along with an identification key. [ABSTRACT FROM AUTHOR]

Sequential treatments of dewaxed Calamagrostis angustifolia Kom with water (60 °C and 90 °C), 70% ethanol, and 70% ethanol containing 0.2%, 1.0%, 2.0%, 4.0%, and 8.0% NaOH at a solid to liquid ratio of 1:25 (g/mL) at 80 ºC for 3 h yielded 36.2% soluble polysaccharides of the dry dewaxed material. The eight polysaccharide fractions obtained were comparatively studied by sugar analysis, GPC, FT-IR, ¹H and 13 C-NMR, and 2D-NMR (HSQC) spectroscopy. The results showed that the water-soluble polysaccharides might contain noticeable amounts of β-D-glucan, as well as some pectic substances and galactoarabinoxylan. 70% ethanol-soluble polysaccharide was mainly arabinogalactan. The five alkali-soluble hemicelluloses were mainly galactoarabinoxylans. The Ara/Xyl and Ara/Gal values of H5-H8 fractions decreased with the increment of NaOH concentration from 1.0% to 8.0%. Meanwhile, the molecular weights had a declining trend from ~60,000 to ~40,000 g/mol. The smaller sized and more branched polysaccharides tended to be extracted in the early stages under milder conditions, and the larger molecular sized and more linear hemicelluloses tended to be isolated under more highly alkaline conditions. [ABSTRACT FROM AUTHOR]

Abstract: Soil freeze–thaw cycles in the winter-cold zone can substantially affect soil carbon, nitrogen and phosphorus cycling, and deserve special consideration in wetlands of cold climates. Semi-disturbed soil columns from three natural wetlands (Carex marsh, Carex marshy meadow and Calamagrostis wet grassland) and a soybean field that has been reclaimed from a wetland were exposed to seven freeze–thaw cycles. The freeze–thaw treatments were performed by incubating the soil columns at −10 °C for 1 d and at 5 °C for 7 d. The control columns were incubated at 5 °C for 8 d. After each freeze–thaw cycle, the soil solution was extracted by a solution extractor installed in each soil layer of the soil column, and was analyzed for dissolved organic carbon (DOC), NH4 +–N, NO3 −–N and total dissolved phosphorus (TDP). The results showed that freeze–thaw cycles could increase DOC, NH4 +–N and NO3 −–N concentrations in soil solutions, and decrease TDP concentrations. Moreover, the changes of DOC, NH4 +–N, NO3 −–N and TDP concentrations in soil solutions caused by freeze–thaw cycles were different in various sampling sites and soil layers. The increments of DOC concentrations caused by freeze–thaw cycles were greater in the wetland soil columns than in the soybean field soil columns. The increments of NH4 +–N concentrations caused by freeze–thaw cycles decreased with the increase of soil depth. The depth variation in the increments of NO3 −–N concentrations caused by freeze–thaw cycles in the wetland soil columns was different from that in the soybean field soil columns. The decrements of TDP concentrations caused by freeze–thaw cycles were greater in columns of Carex marsh and Carex marshy meadow than in columns of Calamagrostis wet grassland and the soybean field. The study results provide information on the timing of nutrient release related to freezing and thawing in natural versus agronomic soils, and have implications for the timing of nutrient application in farm fields in relation to water quality protection. [Copyright &y& Elsevier]

Abstract: Anthropogenic activities have increased phosphorus (P) inputs to wetland ecosystems. However, little is known about the effect of P enrichment on soil respiration in these ecosystems. To understand the effect of P enrichment on soil respiration, we conducted a field experiment in Calamagrostis angustifolia-dominated freshwater marshes, the Sanjiang Plain, Northeast China. We investigated soil respiration in the first growing season after P addition at four rates (0, 1.2, 4.8 and 9.6 g P m−2 year−1). In addition, we also examined aboveground biomass, soil labile C fractions (dissolved organic C, DOC; microbial biomass C, MBC; easily oxidizable C, EOC) and enzyme activities (invertase, urease and acid phosphatase activities) following one year of P addition. P addition decreased soil respiration during the growing season. Dissolved organic C in soil pore water increased after P addition at both 5 and 15 cm depths. Moreover, increased P input generally inhibited soil MBC and enzyme activities, and had no effects on aboveground biomass and soil EOC. Our results suggest that, in the short-term, soil respiration declines under P enrichment in C. angustifolia-dominated freshwater marshes of Northeast China, and its extent varies with P addition levels. [Copyright &y& Elsevier]

In a secondary successional community, we focused on the role of local dispersion mediated by clonal growth in the density and spatial patterning of tillers of three dominant grass species ( Elymus repens, Brachypodium pinnatum and Calamagrostis epigejos) on the plant neighbourhood scale. We also asked whether the spatial pattern/density of their tillers were linked to the local diversity structure. In ten 75 cm × 75 cm quadrats for each of the three species, we quantified i) the clonal morphology patterns from measuring spacer length, branching rate and the number of clumping tillers per module, ii) the spatial patterns and density of tillers in grids at four different resolutions (cell sizes varied between 1 cm × 1 cm; 2.5 cm × 2.5 cm; 5 cm × 5 cm and 7.5 cm × 7.5 cm), and iii) local species richness and local dominance based on botanical relevés. Then, we explored the relationships between iv) the clonal architecture pattern and the density/spatial pattern of tillers and v) the density/spatial pattern of tillers and local diversity variables, through regression analyses. Aggregation intensity on the smallest scales and tiller density were negatively linked to spacer length and positively linked to branching rate and number of clumping tillers. Species richness and dominance in quadrats were negatively and positively linked to tiller density, respectively. Dominance was positively linked to aggregation intensity on a 1-cm scale. This study emphasized and quantified the importance of clonal growth in the intensity and quality of grass tiller patterning in space on the plant neighbourhood scale. Our approach allowed the accurate positioning of species, or even clones on the phalanx-guerrilla continuum. This should help us to understand how dominant grass species affect the dynamics of stand communities. [ABSTRACT FROM AUTHOR]

Abstract: The main aim of the study was to evaluate the strategies for coping with arsenic toxicity developed by the mine species (Calamagrostis arundinacea, Fragaria vesca, Stachys sylvatica, and Epilobium parviflorum), and to compare results obtained from plants exposed to arsenic present in contaminated soil (2000–3500mg/kg dw) and in hydroponic solution (2μM and 12μM arsenate). Here we report basic differences in plant responses to arsenic depending on growth conditions (hydroponic/soil) with respect to uptake, root-to-shoot translocation, distribution, and detoxification/speciation. Calamagrostis has the highest level of As-tolerance among the tested species. When grown in soil, it accumulated the highest amount of As in roots and shoots relative to other species, however, when exposed to arsenic in hydroponics, it had lower As concentrations. The efficiency of arsenic root-to-shoot translocation was also different, being less effective in soil-grown Calamagrostis compared with hydroponics. Furthermore, in Calamagrostis exposed to arsenate in liquid medium, As(III) was the predominant arsenic form, in contrast to plants grown in As-contaminated soil, in which As(V) predominated. In addition, comparison of the level of phytochelatins showed that only PC2 was detected in plants from hydroponics, whereas in those from soil, additionally PC3 and PC4 were found. The results show that the basic components of a plant’s response to arsenic, including uptake, accumulation as well as detoxification, change depending on the experimental conditions (arsenic in liquid medium or contaminated soil). [Copyright &y& Elsevier]

Calamagrostis pseudopurpurea is one of only a few endemic species in Germany and is confined to the catchment area of the River Mulde in the states of Saxony and Saxony-Anhalt. We studied the genetic structure and seed viability across its entire distribution area. Patterns of random amplified polymorphic DNA (RAPD) variation were analysed using 183 individuals from 43 stands in order to assess the overall genetic structure and the extent of clonality. In addition, four related Calamagrostis species ( C. canescens, C. epigejos, C. phragmitoides and C. villosa) were included in our study to consider the probable phylogenetic origin of C. pseudopurpurea. We detected two clearly different RAPD phenotypes of C. pseudopurpurea, each distributed along the river banks of two spatially isolated stream courses. Both phenotypes are present downstream of the confluence. Our results indicate that C. pseudopurpurea originates from two distinct periods of hybridisation between the same parental taxa, and that clonal propagation is most likely the main reproduction method. In line with its hybrid origin, embryos of sampled C. pseudopurpurea caryopses were found to be mostly degraded or unviable over several years. Calamagrostis pseudopurpurea is genetically closer to C. canescens and C. phragmitoides than it is to other studied species, but C. canescens and C. phragmitoides have not been proven to be direct parental taxa of C. pseudopurpurea. Calamagrostis pseudopurpurea should therefore still be treated as a separate species that needs special attention from a conservation point of view. [ABSTRACT FROM AUTHOR]

Calamagrostis villosa has recently expanded in Nardus stricta-dominated sub-alpine grassland of the Giant Mountains (Krkonoše/Karkonosze, the Czech Republic). To investigate whether this expansion has been promoted by high nitrogen deposition or by the cessation of agricultural management, grassland plots dominated by C. villosa were manipulated with four treatments: control (Con), fertilised (Fer), cut (Cut) and cut–fertilised (Cut–Fer). NH4NO3 was used at the rate of 30kgNha−1 and fertilisation and cutting were performed once a year after data collection in late July between 2000 and 2006. Plant species composition (analysed by RDA) was significantly influenced by cutting but not by fertilisation. Cutting reduced the cover, biomass, sward height and tiller density of C. villosa. Seedlings of N. stricta and panicles of C. villosa were recorded only in plots with cutting management. To investigate the effect of treatments on the spread of C. villosa, grassland sods dominated by N. stricta were transplanted into the experimental plots. Six years later, the density and cover of C. villosa spreading into the N. stricta sods were highest in Fer treatment. C. villosa was recognised as a defoliation-sensitive species and this sensitivity cannot be overcome by an increase in N supply. Recent expansion of C. villosa in the sub-alpine grassland can by explained by a long-term succession after the cessation of agricultural management and an increase in the N availability in recent decades. [Copyright &y& Elsevier]

The Matanzas Prairie Nature Preserve is located near Bath, Mason County, Illinois, in the extensive glacial sand deposits associated with the Illinois River. This Preserve contains the only remaining high quality wet-mesic sand prairie, shrub prairie, and sedge meadow associated with the Illinois River sand deposits. The sedge meadow, about 5 ha in size, was dominated by Carex stricta (Importance Value or IV of 66.6 out of 200), Calamagrostis canadensis, and Rosa palustris (both with IV's of 28.3). The wet-mesic sand prairie occurred on slightly higher ground and was dominated by Solidago canadensis (IV of 34.2), Andropogon gerardii (IV of 25.9), Carex stricta (IV of 21.9), Poa pratensis (IV of 18.0), and Euthamia graminifolia (IV of 17.7). Parts of the Preserve were shrub prairie with a ground layer similar to the wet-mesic sand prairie community. A total of 340 species of vascular plants were encountered on the Preserve: 5 fern and fern-allies; 100 monocots; and, 235 dicots. Except for Poa pratensis, which was among the dominant species in the wet-mesic sand prairie and shrub prairie, the 38 exotic species were rarely encountered (11% of the flora). The Floristic Quality Index (including exotic species) for the sedge meadow was 38.80, the wet-mesic sand prairie 43.65, and the shrub prairie 31.76. [ABSTRACT FROM AUTHOR]

Question: How does the dominance of Calamagrostis epigejos influence species turnover of a grassland? Location: Loess grassland at the foothills of Bükk Mountains, Hungary (47°54' N., 20°35' E). Methods: Presence/absence of vascular plants and different performance attributes of C. epigejos were recorded in a plot-subplot system between 2002 and 2005. Appearance and disappearance rates of grassland species were calculated for pairs of consecutive years. 1. Mean appearance and disappearance rates were compared in grassland plots dominated by C. epigejos and in plots free from this species, based on Monte Carlo randomization. 2. Mean appearance rates were assessed for categories of C. epigejos performance and their confidence intervals were calculated via Monte Carlo randomization. For two performance variables (percentage cover and shoot number) analyses were performed at two spatial scales. Results: 1. C. epigejos.-dominated plots differed from unaffected ones by significantly lower appearance rates. 2. Change in appearance rates was best explained by differences in percentage cover of C. epigejos. Coarse-scale C. epigejos performance had a closer correspondence with appearance rate change than fine-scale performance. Low level C. epigejos performance enhanced appearance rate compared to intact stands, while high level performance decreased it, regardless of the choice of performance measure. Conclusions: C. epigejos lowers species number by hindering reappearance of species of the original grassland. This is best explained by the increased shading effect at the coarse scale. The marked non-linear initial enhancement in appearance rate, however, can also be taken as an early sign of future species loss. [ABSTRACT FROM AUTHOR]

Abstract: The sulfur cycle and its compartmental distribution within an atmosphere-plant-soil system was studied using a compartment model in the typical meadow Calamagrostis angustifolia wetland in the Sanjiang Plain Northeast China. The results showed that in the typical meadow C. angustifolia wetland ecosystem, soil was the main storage compartment and current hinge of sulfur in which 98.4% sulfur was accumulated, while only 1.6% sulfur was accumulated in the plant compartment. In the plant subsystem, roots and litters were the main storage compartment of sulfur and they remained 83.5% of the total plant sulfur. The calculations of sulfur turnover through the compartments of the typical meadow C. angustifolia wetland ecosystem demonstrated that the above-ground component took up 0.99 gS/m2 from the root, of which 0.16 gS/m2 was translocated to the roots and 0.83 gS/m2 to the litter. The roots took in 1.05 gS/m2 from the soil, subsequent translocation back to the soil accounted for 1.31 gS/m2, while there was 1.84 gS/m2 in the litter and the net transfer of sulfur to the soil was more than 0.44 gS/(m2 · a). The emission of H2S from the typical meadow C. angustifolia wetland ecosystem to the atmosphere was 1.83 mgS/(m2 · a), while carbonyl sulfide (COS) was absorbed by the typical meadow C. angustifolia wetland ecosystem from the atmosphere at the rate of 1.76 mgS/(m2 · a). The input of sulfur by the rainfall to the ecosystem was 4.85 mgS/m2 during the growing season. The difference between input and output was 4.78 mgS/m2, which indicated that sulfur was accumulated in the ecosystem and may cause wetland acidify in the future. [Copyright &y& Elsevier]

How resource availabilities affect the competitiveness of Canada bluejoint grass [Calamagrostis canadensis (Michx.) P. Beauv., hereafter referred to as bluejoint] is poorly understood. Bluejoint is a widespread grass species in boreal forests and competes with tree species such as white spruce [Picea glauca (Moench) Voss] for belowground resources (e.g., soil N and water) when their supply is limited. In this greenhouse-based study, we tested the following hypotheses: (i) bluejoint competition reduces white spruce growth when belowground resource availabilities are limited; (ii) greater N and water availabilities may increase bluejoint competition and its adverse effects on white spruce growth; and (iii) white spruce foliar δ13C and δ15N are affected by soil N and water availabilities and bluejoint competition. A 2 × 2 2 (competition × N availability × water availability) factorial experiment was conducted using pots of planted white spruce seedlings with or without bluejoint. Bluejoint competition reduced the volume index (diameter² × height) of white spruce by 50%. The competitiveness of bluejoint appeared to be independent of resource availabilities, but bluejoint had greater growth response to increased N availability than white spruce. Bluejoint competition depleted white spruce foliar δ13C and δ13N by 1.2 and 1.2‰ respectively, even under adequate water supply, indicating that N deficiency caused by bluejoint competition had a dominant effect (increasing 13C discrimination during photosynthesis) compared with the potential effect of drought stress on foliar δ13, and that strong NH4 uptake by bluejoint may have prevented significant soil N losses and 15N enrichment through nitrification and subsequent denitrification. [ABSTRACT FROM AUTHOR]

To examine the hybrid origin of the diploid grass Calamagrostis longiseta var. longe-aristata, we performed morphometric and genetic analyses of this taxon and its putative parental taxa. The morphometric analyses revealed that, in general, C. longiseta var. longe-aristata is morphologically intermediate between C. longiseta var. longiseta and C. fauriei. Previous studies have reported that some hybrids exhibit transgressive characters but others do not; the latter is the case for C. longiseta var. longe-aristata. Their absence may be due to the ecological adaptation to environments intermediate between those inhabited by the putative parental taxa, and therefore the transgressive characters have not been selected. Nevertheless, there is no direct evidence for adaptive value of the characters examined in this study and only a small part of all characters potentially responsible for adaptation was investigated. An alternative hypothesis about the absence of transgressive characters in C. longiseta var. longe-aristata is that it is at an early stage of hybrid speciation. Random amplified polymorphic DNA (RAPD) analyses showed that individuals of C. longiseta var. longe-aristata were placed in both of the clusters formed by each putative parental taxon. Greater genetic diversity was observed in C. longiseta var. longe-aristata than in its putative parental taxa. All here reported findings support the scenario that C. longiseta var. longe-aristata is of hybrid origin, having evolved from C. longiseta var. longiseta and C. fauriei. [ABSTRACT FROM AUTHOR]

Abstract: Populations of Calamagrostis arundinacea (L.) Roth. and Calamagrostis villosa (Chaix ex Vill.) J.F. Gmel. were investigated by electrophoresis in respect of variability of six peroxidase loci. Anodally migrating allozymes discriminate between the species. Genotype frequencies of cathodally migrating loci prove to be very informative in the description of the hybridization process, attesting to unidirectional transfer of genes from C. arundinacea to C. villosa in some populations. The results are discussed in the context of hypotheses explaining the distribution of plants in mountain valleys. [Copyright &y& Elsevier]

Abstract: Using the static chamber and Chromatograph method, H2S and COS emission fluxes from the mash meadow Calamagrostis angustifolia and typical meadow C. angustifolia in Sanjiang Plain Northeast China were measured during growth season (5–9 month), the results showed that the seasonal and diurnal variations of H2S and COS emission fluxes were obvious, the mean emission fluxes of H2S and COS from the mash meadow C. angustifolia were 0.34 and −0.29μgSm−2 h−1, respectively, and from typical meadow C. angustifolia were 0.14 and −0.20μgSm−2 h−1, respectively, the mean emission fluxes of H2S and COS from the mash meadow C. angustifolia were both higher than their from typical meadow C. angustifolia. The C. angustifolia wetlands both can emit H2S to the atmosphere and absorb COS from the atmosphere in the growth season. The H2S and COS emission fluxes were affected by the C. angustifolia growth, and the H2S emission peak and COS absorbed peak were observed during the bloom growth time. There were negative correlations of H2S and COS emission fluxes in C. angustifolia Wetlands. [Copyright &y& Elsevier]

There is a growing interest in the effects of deciduous trees on biodiversity, soil processes and long-term productivity in boreal, conifer-dominated forests. This study investigated whether individual birch trees allowed to grow to maturity in the coniferous forest can have a local effect on floristic richness and regeneration of tree saplings. The ground vegetation was compared in 2 m radius plots around the stem under the canopies of matched conifer–deciduous trees in a mature, conifer-dominated forest, and included in the analysis variables that could potentially mediate the tree effect (soil pH, cover of lichens, bryophytes, leaf and needle litter). The field layer vegetation was more species rich under birch (Betula pendula and B. pubescens) than under conifers (Picea abies and Pinus sylvestris), and several vascular plant species (including saplings of tree species) occurred more often under birch than under conifers. However, when the effect of the number of subordinate trees was taken into account the difference between birch and pine was not significant. The number of tree regenerations (saplings) was lowest under pines, but did not differ between spruce and birch. There were no effects of the canopy species on soil pH or on cover of lichens and bryophytes. The difference in diversity may be caused by the different effects of leaf and needle litter, and it is also likely that canopy structure has an influence via interception and throughfall and by affecting the light and microclimate. [ABSTRACT FROM AUTHOR]

This first revision of the genus Deyeuxia in Argentina revealed 58 native taxa from America, three of them endemic to Argentina, and the remaining ones also growing in Bolivia, Brasil and Chile. Three new taxa are described for science: Deyeuxia alba subsp. breviaristata (Argentina, Brasil and Uruguay); Deyeuxia heterophylla var. puberilemma (Perú); Deyeuxia trichodonta var. hirsuta from (Argentina: Salta). The following taxa are new records for Argentina, Bolivia, Chile and Ecuador: Deyeuxia brevifolia var. brevifolia and Deyeuxia brevifolia var. expansa (Chile); Deyeuxia cabrerae var. cabrerae, D. cabrerae var. aristulata (Chile); D. cabrerae var. trichopoda (Chile); Deyeuxia curta (Ecuador); D. diemii (Chile); Deyeuxia filifolia (Chile); Deyeuxia hackelii (Chile); Deyeuxia minima (Argentina and Ecuador); Deyeuxia sclerantha (Ecuador); Deyeuxia spicigera var. spicigera Chile); Deyeuxia spicigera var. cephalotes (Argentina) and Deyeuxia trichodonta var. trichodonta (Bolivia). The new name Deyeuxia nana, for Agrostis caespitosa, and the following new combinations are established: Deyeuxia reitzii, Deyeuxia rupestris f. pilosa, Deyeuxia rupestris var. minor, D. tarmensis var. macrochaeta, and Deyeuxia velutina var. nardifolia. New synonyms are established for Deyeuxia heterophylla (Calamagrostis mulleri, Calamagrostis macbridei); Deyeuxia rupestris f. pilosa (Calamagrostis leonardii, Calamagrostis longearistata f. pilosa) and Calamagrostis epigeios (Calamagrostis chilensis). This revision includes a critical evaluation of morphological characters (some of them studied by SEM) with taxonomic value at the generic and species level, and relationships among Deyeuxia and its closest genera are discussed. Nomenclatural considerations about problematic taxa, keys to Deyeuxia and related genera, and also to the species and subspecific taxa, descriptions, synonyms, illustrations, geographical distribution, ecological observations and vernacular names for every species are presented in detail. [ABSTRACT FROM AUTHOR]

Abstract: The structure of a clonal plant population is studied in Calamagrostis canescens, a perennial grass colonizing forest areas which have become open due either to tree-felling or windthrow. A scale of ontogenetic stages is defined where the stages of individual plants (tussocks) are described in terms of their morphology. No strict correspondence has been revealed between the stage of the tussock and its chronological age. Therefore, the formal classification of individuals considers both the age and the stage in ontogenesis, which results in a life-cycle graph defined on a finite two-dimensional lattice. The origin of individuals (seed reproduction or vegetative propagation) has also appeared to predetermine different pathways within the life cycle. The traditional way to formally relate population dynamics to the population structure leads to a matrix model, while the special pattern of the life-cycle graph, together with that of the corresponding population vector, results in a non-traditional form of the projection matrix. This form differs from the classical Leslie and Lefkovitch ones with certain nonzero entries (vital rates), which complicates the routine mathematical analysis of the model. We demonstrate that the classical model outcomes, like the asymptotic rate of population growth (or decline), the equilibrium population structure and the reproductive values of the population groups can still be obtained from a given set of the age-stage-specific vital rates. The potential-growth indicator is also shown calculable from the vital rates and it appeared useful in a procedure of model calibration on a short series of empirical data. The model can thus serve as a research tool specialised for applied problems which may be associated with the double-structured population dynamics in a clonal plant species. [Copyright &y& Elsevier]