Phylogeographical history of the widespread meadow fescue (Festuca pratensis Huds.) inferred from chloroplast DNA sequences

Aim Here we explore the variation in chloroplast DNA (cpDNA) in a widespread Eurasian diploid forage grass, meadow fescue (Festuca pratensis Huds.), to address its phylogeographical history. In particular, we aim to answer whether the post‐glacial migration routes of meadow fescue are associated with the spread of agriculture or concurrent with well‐documented natural migration pathways from glacial refugia. Location A total of 56 Eurasian accessions of F. pratensis were analysed, representing the entire native distribution area as well as non‐native areas in northernmost Europe. Methods Based on initial sequencing of 10 non‐coding cpDNA regions, three regions were sequenced for all F. pratensis accessions. For reference, three closely related species [the diploid Lolium perenne L. and the polyploids Festuca arundinacea Schreb. and Festuca gigantea (L.) Vill.] were also sequenced, as well as the more distantly related Festuca ovina L. Divergence times were estimated assuming a simple molecular clock, calibrated using a previously published estimate of 9 Myr for the divergence between fine‐leaved (F. ovina) and broad‐leaved fescues (F. pratensis, F. arundinacea and F. gigantea). Results Limited, but geographically structured, cpDNA variation was observed in F. pratensis. Three haplotypes, estimated to have diverged 0.16 Ma, were identified: one western European (A), one with a wide eastern distribution from central‐eastern Europe into Asia (B) and one Caucasian (C). The haplotypes of the polyploids and L. perenne were estimated to have diverged from haplotype A in F. pratensis 0.8–1.3 Ma. Main conclusions We found no definite evidence for migration of the diploid F. pratensis associated with the spread of agriculture from the Fertile Crescent after the last glaciation. The distinct geographical structuring of the present‐day variation in cpDNA can rather be explained by northwards expansion of the western haplotype from an Iberian refugium, expansion of the eastern haplotype from an unlocated (south‐)eastern refugium and glacial survival without subsequent expansion from a Caucasian refugium. The high level of cpDNA divergence observed between this diploid and the polyploids which have probably been derived from it may suggest that the very low level of cpDNA variation in the diploid is caused by a recent bottleneck. Today, F. pratensis is widespread in the open agricultural landscape but appears otherwise confined to naturally open habitats such as river banks, and its populations may have been decimated when dense forests dominated in the previous interglacial.     

Nutrient conservation strategies in native Andean‐Patagonian forests

Abstract. Nutrient conservation in vegetation affects rates of litter decomposition and soil nutrient availability. Although resorption has been traditionally considered one of the most important plant strategies to conserve nutrients in temperate forests, long leaf life‐span and low nutrient requirements have been postulated as better indicators. We aimed at identifying nutrient conservation strategies within characteristic functional groups of NW Patagonian forests on Andisols. We analysed C‐, N‐, P‐, K‐ and lignin‐concentrations in mature and senescent leaves of ten native woody species within the functional groups: broad‐leaved deciduous species, broad‐leaved evergreens and conifers. We also examined mycorrhizal associations in all species. Nutrient concentration in mature leaves and N‐ resorption were higher in broad‐leaved deciduous species than in the other two functional groups. Conifers had low mature leaf nutrient concentrations, low N‐resorption and high lignin/N ratios in senescent leaves. P‐ and K‐resorptions did not differ among functional groups. Broad‐leaved evergreens exhibited a species‐dependent response. Nitrogen in mature leaves was positively correlated with both N resorption and soil N‐fertility. Despite the high P‐retention capacity of Andisols, N appeared to be the more limiting nutrient, with most species being proficient in resorbing N but not P. The presence of endomycorrhizae in all conifers and the broad‐leaved evergreen Maytenus boaria, ectomycorrhizae in all Nothofagus species (four deciduous, one evergreen), and cluster roots in the broad‐leaved evergreen Lomatia hirsuta, would be possibly explaining why P is less limiting than N in these forests.     

Habitat requirements of the Seychelles Black Paradise Flycatcher Terpsiphone corvina: a re-evaluation of translocation priorities

The critically endangered Seychelles Black Paradise Flycatcher Terpsiphone corvina was once found on at least five of the inner (granitic) islands in the Seychelles archipelago, western Indian Ocean. Currently, it is only found on two islands, with c. 98% of the world population (c. 150–200 individuals) occurring on the 10‐km² island of La Digue. Creation of additional island populations is therefore considered crucial in improving its conservation status. The presence of native broad‐leaved plateau forest in proximity to wetland areas is proposed as an important selection criterion when considering the suitability of other islands for translocation, due to the presumed importance of insect prey (dependent on water) in the diet. We quantified habitat use, territory composition, the effect of water on invertebrate abundance, and foraging and breeding success to determine the importance of native broad‐leaved woodland and wetland areas for Flycatchers. Flycatcher territories contained significantly more native broad‐leaved woodland (88%) than its availability on the plateau (43%); Flycatchers used native tree species significantly more for both foraging (81%) and nesting (95%) than their availability within territories (71%); and territory size varied inversely with the density of native broad‐leaved tree species. Native broad‐leaved forest was associated with semipermanent and permanent water bodies and availability of native forest habitat was a good predictor of territory distribution. The number of aerial insects trapped was higher close to water, but there was no effect of the proximity to water on the number of insects counted on foliage. The majority of identified prey species in adult diet were not dependent on water: Orthoptera and Lepidoptera were the most common prey groups, comprising 66% of identified prey items. There was no effect of proximity to water on foraging or breeding success (c. 35%): depredation was the major factor determining breeding success, and accounted for the majority of nest failures. The importance of wetland areas to Flycatchers therefore appears to have been over‐emphasized. The implications for translocation and conservation of the Flycatcher are discussed.     

Seed selection for grassland restoration: competitive effect of a dominant grass is mediated by seed source and nutrient availability

Cultivars are selected for advantageous traits, which may enable them to have a greater competitive effect (CE), particularly under high nutrient conditions. Sites with high nutrient availability may favor the development of dominant grasses rather than subordinate species, especially in nutrient‐limited systems, such as calcareous grasslands. The aim of this experiment was to determine whether seed source influences the CE of a dominant grass on a subordinate species, and whether this relationship is mediated by nutrient availability. A greenhouse experiment with three nutrient levels was established; Dianthus carthusianorum was chosen as the subordinate “phytometer” to detect variation in the CE of different Festuca rubra seed sources. The grass species was sourced from 13 cultivar and 12 commercially propagated, but not selected, wild sources. When CE was calculated from biomass, propagated wild seed sources of F. rubra had a greater CE on the subordinate species than cultivars for medium and high nutrient levels. Based on phytometer height, propagated wild seed sources of F. rubra had a greater CE under all three nutrient levels. Our findings do not support the general notion that cultivars are more competitive than wild genotypes. Thus, the cultivar F. rubra may facilitate the establishment of other species during grassland restoration, particularly under elevated nutrient conditions.     

Spatial dynamics of regeneration in a conifer/broad‐leaved forest in northern Japan

Abstract. This study deals with stand dynamics over a 6‐yr period in a conifer/broad‐leaved mixed forest in Hokkaido, northern Japan. The annual rates of gap formation and recovery were 81.3 m²/ha and 66.7 m²/ha, respectively and turnover time of the canopy was 125 yr. The recruitment processes of the component species in this cool‐temperate forest were governed by different canopy types: gap, canopy edge and closed canopy. Magnolia obovata regenerated in canopy edges, and Acer mono and Prunus ssiori regenerated in canopy edges and gaps. The results suggested that the mosaic structure made up of closed canopy, canopy edge and gap was related to various regeneration niches. Abies sachalinensis had high mortality rates, initiating gap expansion. The transition probabilities from closed canopy or canopy edge to gap for deciduous broad‐leaved trees were lower than for A. sachalinensis, which implies that the difference in degeneration patterns of conifer and broad‐leaved canopies contributes to the heterogeneity of spatial structure in the mixed forests. Spatial dynamics were determined by a combination of gap expansion by A. sachalinensis (neighbour‐dependent disturbance) and gap formation by deciduous broad‐leaved trees (random disturbance).     

Die Buche. Eine Kultur‐ und Wirtschaftsgeschichte

The Beech forests: A cultural and socio‐economic history The German strategy of maintaining biodiversity aims at an establishment of wilderness areas. Mainly beech forests shall serve as UNESCO world heritage. Here we ask, if there are any “natural” beech forests. This tree species is closely linked to human development, and at present this species is less endangered than the accompanying species of Acer, Fraxinus, Quercus and other broad leaved species.     

Woodland restoration on agricultural land: long‐term impacts on soil quality

Woodland restoration is underway globally to counter the negative soil quality and ecological impacts of agricultural expansion and woodland fragmentation, and restore or enhance biodiversity, ecosystem functions and services. However, we lack information about the long‐term effects of woodland restoration on agricultural soils, particularly at temporal scales meaningful to woodland and soil development. This study utilized soil and earthworm sampling across a chronosequence of sites transitioning from “agricultural land” to “secondary woodland” (50–110 years) and “ancient woodland” (>400 years), with the goal of quantifying the effects of woodland restoration on agricultural land, on key soil quality parameters (soil bulk density, pH, carbon and nitrogen stocks, and earthworm abundance, biomass, species richness and diversity). Broad‐leaved woodland restoration led to significantly greater soil organic carbon (SOC) stocks compared to arable land, and young (50–60 years) secondary woodland increased earthworm species and functional diversity compared to both arable and pasture agricultural land. SOC stocks in secondary broad‐leaved woodlands (50–110 years) were comparable to those found in long‐term ancient woodlands (>400 years). Our findings show that broad‐leaved woodland restoration of agricultural land can lead to meaningful soil ecological improvement and gains in SOC within 50–110 years, and provide intel on how restoration activities may be best targeted to maximize soil quality and functions.     

Associations in the midwater zone: The penaeid shrimp funchalia sagamiensis fujino 1975 and pelagic tunicates (order: Pyrosomatida)

An association between the penaeid shrimp Funchalia sagamiensis FUJINO 1975 and pelagic tunicates of the Order Pyrosomatida was confirmed through in situ submersible and shipboard observations. Information on this association, including behavioural, morphological and distributional data is presented. The association is “strong”;, possibly obligate for the shrimp during this life‐history phase, and does not appear to be species‐specific. Further information is presented on the taxonomic standing within the genus Funchalia of the enigmatic species F. sagamiensis. The utility of submersibles for in situ behavioural research is discussed.     

Feedbacks between canopy composition and seedling regeneration in mixed conifer broad‐leaved forests

To address the role of canopy‐seedling feedbacks in the structure and dynamics of mixed conifer broad‐leaved forests in the eastern US, we monitored seedling regeneration patterns and environmental conditions in the understorey of stands dominated by either hemlock (Tsuga canadensis) or red oak (Quercus rubra) for three years. Hemlock seedlings were favoured over other species’ seedlings in hemlock stands (a true positive feedback), due to a combination of high seed inputs, high seedling emergence and relatively high seedling survival during the growing season, which allowed hemlock to remain dominant under its own canopy. Red oak stands favoured a suite of mid‐successional broad‐leaved species over hemlock. A more even age structure of broad‐leaved species in red oak stands revealed that high seedling survival in such stands were driving this feedback. Canopy‐mediated variations in both understorey light availability (1.5% for hemlock vs 3.5% for red oak) and soil pH (3.9 for hemlock vs 4.4 for red oak) were found to be the primary correlates of stand‐level differences in seedling regeneration dynamics. In mixed temperate forests in the eastern US, canopy‐seedling feedbacks could act to slow successional trajectories and contribute to the maintenance of a stable landscape structure over many generations.     

The saproxylic beetle assemblage associated with different host trees in Southwest China

Dead wood is a habitat for many insects and other small animals, some of which may be rare or endangered and in need of effective protection. In this paper, saproxylic beetle assemblages associated with different host trees in the subtropical forests in southwestern China were investigated. A total of 277 species (1 439 specimens) in 36 beetle families were collected from 117 dead wood samples, of which 101 samples were identified and respectively belonged to 12 tree genera. The number of saproxylic beetle species varied greatly among logs of different tree genera, with the highest diversity on logs of Juglans. Generally, broad‐leaved trees had a higher richness and abundance of saproxylic species than coniferous trees. Cluster analysis revealed that assemblages from broad‐leaved tree genera were generally similar (except for Betula) and assemblages from coniferous trees formed another distinct cluster. The subsequent indicator analysis proposed that there are different characteristic species for different cluster groups of host tree genera. In our study, log diameter has no positive influence on beetle species density. Conversely, comparisons of individual‐based rarefaction curves suggested that beetle species richness was highest in the small diameter class both in coniferous and broad‐leaved tree genera. With increased wood decay, proportion of habitat specialists (saproxylic beetles living on one tree genus) decreased, whereas proportion of habitat generalists (living on more than three tree genera) increased. The beetle species density was found to be higher in early stages, and decreased in later stages as well. A negative influence of altitude on saproxylic beetle species richness and abundance was detected. It was indicated that different tree genera and altitudes possibly display cross effects in modulating the altitudinal distribution and host preference of the beetles.     

Forest History as a Basis for Ecosystem Restoration—A Multidisciplinary Case Study in a South Swedish Temperate Landscape

Basic knowledge of the previous forest types or ecosystem present in an area ought to be an essential part of all landscape restoration. Here, we present a detailed study of forest and land use history over the past 2,000 years, from a large estate in southernmost Sweden, which is currently undergoing a restoration program. In particular, the aim was to identify areas with long continuity of important tree species and open woodland conditions. We employed a multidisciplinary approach using paleoecological analyses (regional and local pollen, plant macrofossil, tree ring) and historical sources (taxation documents, land surveys, forest inventories). The estate has been dominated by temperate broad‐leaved trees over most of the studied period. When a forest type of Tilia, Corylus, and Quercus started to decline circa 1,000 years ago, it was largely replaced by Fagus. Even though extensive planting of Picea started in mid‐nineteenth century, Fagus and Quercus have remained rather common on the estate up to present time. Both species show continuity on different parts of the estate from eighteenth century up to present time, but in some stands, for the entire 2,000 years. Our suggestions for restoration do not aim for previous “natural” conditions but to maintain the spatial vegetational pattern created by the historical land use. This study gives an example of the spatial and temporal variation of the vegetation that has historically occurred within one area and emphasizes that information from one methodological technique provides only limited information about an area’s vegetation history.     

Landscape Pattern Dynamics and Mechanisms during Vegetation Restoration: A Multiscale,Hierarchical Patch Dynamics Approach

The spatial pattern of vegetation changes during ecological restoration, and these changes are affected by the process of restoration. The objective of this study was to integrate the pattern and mechanism of forest restoration in the Dinghushan Nature Reserve (DNR), Guangdong, China, based on data from remote sensing and long‐term field observations. We studied the pattern dynamics of three main forest types and their underlying mechanisms during restoration following a multiscale, hierarchical patch dynamics framework that integrates population, community, and landscape processes. Remote sensing data were used to determine the changes in landscape pattern during different periods of forest restoration from 1978 to 2006. At the landscape scale, the number, area, and perimeter of the needle/broad‐leaved mixed forest (MF) and the evergreen broad‐leaved forest (BF) increased, whereas those of the tropical needle‐leaved forest (NF) decreased during succession. Our analysis based on long‐term field observations indicated that the change rate of NF was lower than that of MF during 1981–1996, but became much higher during 1996–2007. The rate of change in landscape pattern and the progression of succession stages were consistent with each other. Our results also showed that species regeneration and community succession are the biological basis of forest landscape dynamics during vegetation restoration. Landscape pattern analysis allowed us to show “what” happened during vegetation restoration and “where,” and population and community analysis indicated “why” and “how” it happened.     

Sapling survival and growth of coniferous and broad‐leaved trees in successional highland habitats in Mexico

Abstract. We assessed survival and growth of transplanted saplings of understory broad‐leaved trees (Oreopanax xalapensis, Rapaneajuergensenii, Rhamnus sharpii and Tern‐stroemia lineata) and canopy conifers (Abies guatemalensis, Pinus ayacahuite and P. pseudostrobus) into Grassland (GR), Mid‐Successional Oak Forest (MS), and Old‐Growth Oak Forest (OF) stands in the central highlands of Chiapas, Mexico. A total of 727 plants were monitored over eight years. The results suggest habitat preferences of the studied species that should be considered for their conservation oriented management. Conifers had highest survival and growth in GR, while broad‐leaved trees survived better under sparse canopy in MS, but grew tallest in full light. Saplings of all species in dense canopy sites in OF were smaller, and the survival of conifers was lower. An integrated response index (IRI) calculated for each species with survival and relative growth rates showed similar trends. Re‐introduction of the endangered A. guatemalensis is possible in open habitats if fire, trampling and grazing are suppressed. Open habitats in current man‐made landscapes in the highlands of Chiapas may limit the establishment of understory trees requiring partial shade. Inclusion of such species in restoration programs has not been usual so far; yet, local and global interest in native species for such programs is increasing. Information on the response of these kind of species in contrasting habitats may help to incorporate them in the management of high‐diversity forests that may follow pine plantations.     

A survey of the genus Festuca L. (Poaceae) in Italy. Festuca gamisansii Kerguélen subsp. aethaliae,subsp. nova

ABSTRACT

Festuca gamisansii subsp. aethaliae, endemic to the Isle of Elba (Tuscan Archipelago) is described. The morphological, anatomical, karyological, ecological and chorological characteristics of the species are given. The main characteristics distinguishing F. gamisansii subsp. aethaliae from F. gamisansii subsp. gamisansii occurring in Corsica are also summarized.     

Formation and function of the “Xestoleberis‐spot” in Xestoleberis hanaii (Crustacea: Ostracoda)

The crescent sculpture of the so‐called “Xestoleberis‐spot” develops inside the calcified valve of the family Xestoleberididae. Electron microscopic observations on both, intermoult and postmoult stages of Xestoleberis species reveal that the “Xestoleberis‐spot” system consists of three elements; two calcified chambers, a vesicle of electron‐dense material and an uncalcified procuticle. The formation and function of the “Xestoleberis‐spot” system are discussed. In conclusion, the “Xestoleberis‐spot” system functions as the muscle attachment site for several antennal muscles, and provides the material for chitinous fibers in the exocuticle of outer lamella. The unique cuticular structures of the family Xestoleberididae are due to the “Xestoleberis‐spot” system.     

Robinia pseudoacacia as a surrogate for native tree species for saproxylic beetles inhabiting the riparian mixed forests of northern Italy

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Development of novel microsatellite markers for the grassland species Lolium multiflorum,Lolium perenne and Festuca pratensis

Twelve microsatellite markers were isolated from Lolium multiflorum. Allelic variability and cross‐species amplification were assessed on 16 individuals of each of the three grassland species L. multiflorum, Lolium perenne and Festuca pratensis. Cross‐species amplification success was 100% for L. perenne and 83% for F. pratensis. The number of alleles detected ranged from one to 14 with an average of 3.4. While three microsatellite loci were polymorphic in all three species, one marker produced species‐specific alleles in all three species. These microsatellite markers provide a valuable tool for population genetic studies within and among species of the Festuca–Lolium complex.     

Ramet Population Structure of Fargesia nitida （Mitford） Keng f. et Yi in Different Successional Stands of the Subalpine Coniferous Forest in Wolong Nature Reserve

Forest structure and succession in Wolong Nature Reserve is influenced by the understory dwarf bamboo population. However, less is known about how the forest succession affects the dwarf bamboo population. To examine the bamboo ramet population growth of Fargesla nitida （Mltford） Keng f. et Yi and to determine how ramet population structure varies along the succession of coniferous forest, we sampled ramet populations of F. nitida from the following three successional stages： （i） a deciduous broad-leaved （BL） stand; （ii） a mixed broad-leaved coniferous （MI） stand; and （ill） a coniferous （CF） stand. We investigated the population structure, biomass allocation, and morphological characteristics of the bamboo ramet among the three stand types. Clonal ramets, constituting the bamboo population, tended to become short and small with succession. The ramet changed towards having a greater mass investment in leaves, branches and underground roots and rhizomes rather than in the culm. With respect to leaf traits, individual leaf mass and area in the BL stand were markedly bigger than those In both the MI and CF stands, except for no significant difference in specific leaf area. The age distribution showed that the bamboo population approached an older age with succession. The results demonstrate that the ramet population structure of F. nitida is unstable and its growth performance is inhibited by succession.     

An optimal proportion of mixing broad‐leaved forest for enhancing the effective productivity of moso bamboo

Moso bamboos (Phyllostachys edulis) are important forestry plants in southern China, with substantial roles to play in regional economic and ecological systems. Mixing broad‐leaved forests and moso bamboos is a common management practice in China, and it is fundamental to elucidate the interactions between broad‐leaved trees and moso bamboos for ensuring the sustainable provision of ecosystem services. We examine how the proportion of broad‐leaved forest in a mixed managed zone, topology, and soil profile affects the effective productivity of moso bamboos (i.e., those with significant economic value), using linear regression and generalized additive models. Bamboo's diameter at breast height follows a Weibull distribution. The importance of these variables to bamboo productivity is, respectively, slope (25.9%), the proportion of broad‐leaved forest (24.8%), elevation (23.3%), gravel content by volume (16.6%), slope location (8.3%), and soil layer thickness (1.2%). Highest productivity is found on the 25° slope, with a 600‐m elevation, and 30% broad‐leaved forest. As such, broad‐leaved forest in the upper slope can have a strong influence on the effective productivity of moso bamboo, ranking only after slope and before elevation. These factors can be considered in future management practice.     

Hedychium menghaiense (Zingiberaceae), a new species from Yunnan,China

Abstract Hedychium menghaiense X. Hu & N. Liu, a new species of the Zingiberaceae from Yunnan Province, China, is described and illustrated. The new species is currently known only from its type locality, Nannuoshan Mountain, Menghai County, growing under evergreen broad‐leaved forests at altitudes of 1400–1700 m. It is similar to Hedychium forrestii Diels, but differs in its narrower and emarginate labellum folded inwards lengthwise, narrower staminodes, and scarlet stamen. The recognition of the new species is supported by the results from analysis of sequence‐related amplified polymorphism markers.