Seasonal patterns of life cycle of ground beetle <Emphasis Type="Italic">Carabus nitens</Emphasis> (Coleoptera,Carabidae) in southern tundra

Seasonal dynamics of activity and demographic structure of Carabus nietens in the forest-tundra and southern tundra of the Kanin Peninsula was studied. In the northernmost range, the species has a one-year life cycle with reproduction in the early season and summer larvae. C. nitens demonstrated elongated period of development from egg to imago compared to the temperate zone in the polar region. At the same time, overwintered beetles rapidly matured and the reproduction period was reduced to three decades. This synchronizes larval development and the young generation emergence. The northern populations have increased life span of imago, which leads to repeated postwinter reproduction during several seasons. As a result, the abundance of the northern C. nitens populations remains high.     

Species radiation in the Alps: multiple range shifts caused diversification in Ringlet butterflies in the European high mountains

The distributions of European high mountain species are often characterised by small and geographically isolated populations and, in many cases, have highly complex biogeographic histories. The butterfly genus Erebia represents one of the best examples for small-scale diversification in the European high mountain systems and therefore to understand speciation processes and associated range dynamics of high mountain species. In this study, we analysed 17 polymorphic allozyme loci of 1731 individuals from 49 populations representing four species, one of which has three subspecies: Erebia nivalis; Erebia tyndarus; Erebia ottomana; and Erebia cassioides cassioides, Erebia cassioides arvernensis, and Erebia cassioides neleus. Samples were collected in the high mountain systems of Europe (i.e. Pyrenees, Massif Central, Alps, Apennines, Carpathians, Balkan high mountains). Genetic analyses supported all previously accepted species. However, the genetic differentiation within E. cassioides sensu lato into three geographically delimited groups is justifying species rank: E. arvernensis distributed in the Pyrenees, Massif Central and western Alps; E. cassioides sensu stricto in the eastern Alps and Apennines; and E. neleus in the Balkan mountains and the south-western Carpathians. While the differentiation between western Alps and Massif Central as well as eastern Alps and Apennines was low, the Pyrenees as well as the south-western Carpathians were significantly differentiated from the other regions within the respective taxon. In general, the differentiation among the populations of E. neleus was stronger than between populations of the other taxa. Within E. cassioides, we found a west-east gradient of genetic similarity over the eastern Alps. Based on the obtained genetic structures, we are able to delineate glacial refugia and interglacial range modifications. Based on the genetic structures and genetic diversity patterns, we conclude that, triggered by the glacial-interglacial cycles, repeated range modifications have taken place with subsequent differentiation and speciation in the region of the Alps and Balkans. Colonisations to Pyrenees (E. arvernensis pseudomurina, E. arvernensis pseudocarmenta), Massif Central (E. ottomana tardenota, E. a. arvernensis) and Apennines (E. cassioides majellana) appear to be recent and most probably not older than the last interglacial period.     

Isolation of <Emphasis Type="Italic">Campylobacter</Emphasis> spp. from Three Species of Antarctic Penguins in Different Geographic Locations

The presence of Campylobacter species was studied in three Antarctic penguin species, Adélie (Pygoscelis adeliae), chinstrap (Pygoscelis antarctica) and gentoo (Pygoscelis papua). A total of 390 penguins were captured in 12 different rookeries along the Antarctic Peninsula with differences in the amount of human visitation: six colonies were highly visited [Stranger Point, King George Island (P. papua and P. adeliae); Hannah Point, Livingston Island (P. papua and P. antarctica); Deception Island (P. antarctica); and Paradise Bay, Antarctic Peninsula (P. papua)], and six colonies were rarely visited [Devil’s Point, Byers Peninsula, Livingston Island (P. papua); Cierva Cove, Antarctic Peninsula (P. papua); Rongé Island (P. papua and P. antarctica); Yalour Island (P. adeliae); and Avian Island (P. adeliae)]. A total of 23 strains were isolated from penguins from nine different rookeries. Campylobacter lari subsp. lari was isolated from eight samples (seven from P. papua and one from P. adeliae); C. lari subsp. concheus from 13 (ten from P. adeliae and three from P. antarctica) and C. volucris from two samples (both from P. papua). We did not find any significant differences in the prevalence of Campylobacter spp. between the populations in highly and rarely visited areas. This is the first report of C. lari subsp. concheus and C. volucris isolation from penguins in the Antarctic region.     

Butterflies (Lepidoptera,Rhopalocera) of West Altai

A total of 176 species of butterflies have been found in West Altai. Their distribution ranges, phenology, biological preferences, and taxonomic structure are analyzed. Numerous Siberian butterfly species from the genera Erebia, Oeneis, Clossiana, Boeberia, and Colias have been found in West Altai which may be accounted for its westernmost position in the mountain system of southern Siberia and very humid climate. At the same time, many western Palaearctic as well as few Middle Asian butterflies have been discovered in West Altai for the first time. West Altai is the region where pairs of sister species which diverged in the Western and Eastern Palaearctic can be found in secondary contact. In this study, a zone of stable secondary sympatry of Melitaea didyma (western element) and M. latonigena (eastern element) as well as that of Maculinea arion (western element) and M. cyanecula (eastern element) has been found. These findings provide the first strong evidence for the distinctness of the species in these sister pairs.     

A new species of the genus <Emphasis Type="Italic">Bibio</Emphasis> (Diptera,Bibionidae) from the tundra of the Asian part of Russia

A new species, Bibio tschernovi Kriv., from the Taimyr Peninsula, the Chukchi Autonomous Area, and Wrangel Island is described. It is closely related to the Palaearctic B. pomonae (Fabr.) and to two North American species, B. bryanti Johnson, 1929 and B. holtii McAtee, 1921, in the wing structure. New data on the distribution of B. nigriventris Haliday, 1833 and B. pomonae (Fabricius, 1775) are presented. A key to the species of the pomonae group, based on males, is presented.     

Changes in the lichen biota of the Lions Rump area,King George Island,Antarctica, over the last 20 years

Climate changes observed in recent years in the maritime Antarctic have affected the tundra vegetation, including plant communities in which lichens are a dominant component. The results of comparative studies (1988 and 1990 vs. 2007 and 2008) on the dynamics of the lichen biota within the Antarctic Specially Protected Area No. 151 (King George Island, Antarctica) minimally influenced by human impact, are presented. This long-term experiment is aimed at determining the trends and rate of changes on lichen biota induced by climate warming and rapid deglaciation. The most significant changes affecting the lichen biota have taken place in the forefield of a glacier and on the young moraines where in the second period of studies three species (Polyblastia gothica, Thelenella kerguelena, Thelocarpon cyaneum) were not refound. There was also a reduction in the number of other sites for some species (e.g. Leptogium puberulum, Staurothelle gelida) caused by substrate desiccation. On the other hand, there was an increase in the range of pioneering species (e.g. Bacidia chrysocolla, Caloplaca johnstonii, Candelariella aurella, Lecanora dispersa) on young moraines recently uncovered by the retreating glacier. The smallest changes were observed on the cliff rocks near penguin colonies.     

A new species of the chironomid genus <Emphasis Type="Italic">Chaetocladius</Emphasis> (Diptera,Chironomidae) from the Novaya Zemlya Archipelago

The new species Chaetocladius makarchenkovi, subfamily Orthocladinae, is described on the basis of examination of adult males found on the Novaya Zemlya Archipelago (Yuzhnyi Island, Pankov Peninsula, Gribovaya Bay). According to the structure of the head, thorax, and anal point of the hypopygium, the species is closely related to Ch. perennis (Meigen), but differs from it in the form and structure of the lower inner volsella, gonostylus, virga of the hypopygium, in the presence of shortened setae on the antennal flagellum, in the lower antenna index AR, and in the smaller number of Ac and Dc setae on the mesonotum.     

Ecology of inshore notothenioid fish from the Danco Coast,Antarctic Peninsula

A total of 1,103 inshore notothenioid fish were caught by means of trammel-nets in 4 sites surrounding Cierva Point (Moss Island 1; Moss Island 2; Sterneck Island; Leopardo Island), Danco Coast, West Antarctic Peninsula, during February and March 2000. The families Nototheniidae, Channichthyidae and Bathydraconidae were represented in the samples, Notothenia coriiceps being the dominant fish of the area. Gobionotothen gibberifrons and Trematomus newnesi followed in importance. In general, the fish sampled agreed in terms of number and mass with those of the South Shetland Islands area, except for a marked higher occurrence of G. gibberifrons in the Danco Coast. This supports the hypothesis that the commercial fishery around the South Shetland Islands at the end of the 1970s was responsible for the decrease in the inshore population of G. gibberifrons in that area during the last 17 years. Information on morphometry, reproduction and diet of the fish species caught is provided.     

Sexual reproduction of clonal dwarf shrubs in a forest–tundra ecotone

Successful sexual reproduction may be more important for regeneration of clonal species in high-latitude and -altitude areas than has been previously suggested. We investigated the potential of Vaccinium myrtillus, V. vitis-idaea and Empetrum nigrum ssp. hermaphroditum (E. hermaphroditum) for sexual reproduction at three sites in the forest–tundra ecotone in Finnish Lapland. We studied whether the potential differs between plant communities, whether disturbance enhances germination, and whether seedling emergence is limited by seed availability. We established a field experiment with disturbance and sowing treatments, and monitored seed and seedling numbers and survival rates for two years. The number of mature seeds of V. myrtillus was higher in plants from the tundra heath than in those from the coniferous and mountain birch forests. The number of mature seeds and seedlings emerging from the seed bank of E. hermaphroditum tended also to be higher in the tundra heath. Disturbance marginally increased the seedling emergence of V. myrtillus and E. hermaphroditum, whereas sowing generally increased the seedling numbers. The seedling number of V. myrtillus was lower in the tundra heath and that of E. hermaphroditum was lower in the coniferous forest than at the other sites. Seedling survival was equal for all plant species at all sites. We conclude that the capacity for sexual reproduction varies among plant communities, and seed availability is a stronger constraint than microsite availability for the studied species. Once the crucial early phase of seedling establishment is overcome, seedling survival enables successful recruitment of V. myrtillus, V. vitis-idaea and E. hermaphroditum in the subarctic area.     

Structure of microbial communities of peat soils in two bogs in Siberian tundra and forest zones

The structure and functional activity of microbial complexes of a forest oligo-mesotrophic subshrub- grass-moss bog (OMB, Central Evenkiya) and a subshrub-sedge bog in the polygonal tundra (PB, Lena River Delta Samoylovsky Island) was studied. Soil of the forest bog (OMB) differed from that of the polygonal tundra bog (PB) in higher productivity (C_org, N_total, P, and K reserves), higher biomass of aerobic chemoorganotrophs (2.0 to 2.6 times), and twice the level of available organic matter. The contribution of microorganisms to the carbon pool was different, with the share of C_mic in C_org 1.4 to 2.5 times higher in PB compared to OMB. Qualitative composition of the methane cycle microorganisms in PB and OMB soils differed significantly. Methanogenic archaea (Euryarchaeota) in the shrub-sedge PB of tundra were more numerous and diverse than in the oligo-mesotrophic bog (OMB) and belonged to six families (Methanomassiliicoccaceae, Methanoregulaceae, Methanobacteriaceae, Methanomicrobiaceaee, Methanosarcinaceae, and Methanotrichaceae), while members of only four families (Methanosarcinacea, Methanobacteriaceae, Methanotrichaceae, and Methanomassiliicoccaceae) were revealed in OMB. In both bogs, methane-oxidizing bacteria belonged to Alphaproteobacteria (II) and Gammaproteobacteria (I). Methanotroph diversity was higher in OMB than in PB. Microbial communities of PB soils had higher potential activity of methanogenesis and methanotrophy compared to those of OMB. Methanogenic and methanotrophic activities in PB were 20 and 2.3 times higher, respectively, than in OMB.     

Heliozoa (Centrohelea,Haptista, Hacrobia) of saline and brackish water bodies and watercourses of Russia

The species composition of centrohelid heliozoa (Centrohelida) in saline and brackish inland water bodies and watercourses with salinity 2.0–42.2‰ was studied in the subarid zone of Russia. Nine species (Polyplacocystis ambigua, Pterocystis foliacea, Choanocystis ebelii, Acanthocystis astrakhanensis, A. dentata, A. myriospina, A. pectinata, A. taurica, A. turfacea) are new for saline and brackish inland waters. A. astrakhanensis and A. taurica are new for the fauna of Orenburg region. The first data on centrohelidian fauna in saline rivers of Elton region were obtained. The fauna comprises Polyplacocystis ambigua, Pterocystis foliacea, A. turfacea and Choanocystis ebelii. C. ebelii is new for the protist fauna of Russia. Five species (Polyplacocystis ambigua, Pterocystis foliacea, A. pectinata, A. dentata, A. taurica) were recorded for the first time in saline and brackish waters and described as eurihaline. Morphological diagnoses of Acanthocystis dentata and A. taurica were completed.     

Morphogenetic diversity of the ectomycorrhizal genus <Emphasis Type="Italic">Cortinarius</Emphasis> section <Emphasis Type="Italic">Calochroi</Emphasis> in the Iberian Peninsula

The taxonomic and genetic diversity of Cortinarius section Calochroi in one of the most biodiversity-rich regions in Europe, the Iberian Peninsula, was investigated through morphological and phylogenetic methods. This combined methodological approach allowed the identification of 15 known species and one new species, Cortinarius ortegae, which is described here. A dichotomous key is provided for field recognition of Calochroi species inhabiting different Iberian and Balearic Island woodlands. Polymorphism analyses within some studied species showed that the distribution of intraspecific lineages is dependent on geography and, in some cases, tree host. Furthermore, the dating analysis suggested that diversification within Calochroi started in the Pliocene and most of the current genetic diversity originated in the Pleistocene. This temporal scenario supports hypotheses in which climatic oscillations in the Quaternary may have been driving the evolution of this group of ectomycorrhizal fungi.     

Garden varieties: How attractive are recommended garden plants to butterflies?

One way the public can engage in insect conservation is through wildlife gardening, including the growing of insect-friendly flowers as sources of nectar. However, plant varieties differ in the types of insects they attract. To determine which garden plants attracted which butterflies, we counted butterflies nectaring on 11 varieties of summer-flowering garden plants in a rural garden in East Sussex, UK. These plants were all from a list of 100 varieties considered attractive to British butterflies, and included the five varieties specifically listed by the UK charity Butterfly Conservation as best for summer nectar. A total of 2659 flower visits from 14 butterfly and one moth species were observed. We performed a principal components analysis which showed contrasting patterns between the species attracted to Origanum vulgare and Buddleia davidii. The “butterfly bush” Buddleia attracted many nymphalines, such as the peacock, Inachis io, but very few satyrines such as the gatekeeper, Pyronia tithonus, which mostly visited Origanum. Eupatorium cannibinum had the highest Simpson’s Diversity score of 0.75, while Buddleia and Origanum were lower, scoring 0.66 and 0.50 respectively. No one plant was good at attracting all observed butterfly species, as each attracted only a subset of the butterfly community. We conclude that to create a butterfly-friendly garden, a variety of plant species are required as nectar sources for butterflies. Furthermore, garden plant recommendations can probably benefit from being more precise as to the species of butterfly they attract.     

Lifting the curtain on the freshwater mussel diversity of the Italian Peninsula and Croatian Adriatic coast

Freshwater mussels of the order Unionida have been dramatically declining globally. Despite their ecological importance, conservation of these animals has been hindered by unresolved taxonomy and a lack of data on the distribution and status of populations, especially in southern Europe. Although the Italian Peninsula has been noted as a centre of endemism and one of the major refugia of the glacial ages for several taxa, few studies have been performed on the genetic diversity of Unionida. Most importantly, the taxonomic status of several freshwater mussel populations of the Italian Peninsula is still unresolved. Here we present the first comprehensive dataset for the Unionida of the region spanning Italy and the coastal Croatian region (west of the Dinaric Alps). In total, 191 specimens were collected (85 Anodonta, 64 Unio, 17 Microcondylaea bonellii and 25 Sinanodonta woodiana) from 34 sites across the Italian Peninsula and coastal Croatian river basins for molecular identification (COI, 16S and 28S). Genetic analyses were performed to understand major phylogenetic and phylogeographic patterns. Seven species were detected: three Anodonta species (A. anatina, A. cygnea and A. exulcerata), two Unio species (U. mancus and U. elongatulus), Microcondylaea bonellii, and the invasive Sinanodonta woodiana. The presence of three endemic species (A. exulcerata, U. elongatulus and M. bonellii) confirms the importance of the region as a centre of endemism for freshwater mussels. The Apennine Mountains act as an important biogeographic barrier.     

<Emphasis Type="Italic">Viola woosanensis</Emphasis>, a recurrent spontaneous hybrid between <Emphasis Type="Italic">V. ulleungdoensis</Emphasis> and <Emphasis Type="Italic">V. chaerophylloides</Emphasis> (Violaceae) endemic to Ulleung Island,Korea

Ulleung Island is an oceanic volcanic island in Korea, which has never been connected to the adjacent continent. Previous studies highlighted Ulleung Island as an excellent system to study the pattern and process of early stages of flowering plant evolutions on oceanic island. The predominant mode of speciation in flowering plants on Ulleung Island appears to be anagenesis. However, the potentially important role of hybrid speciation among incompletely reproductively isolated lineages cannot be ruled out. Viola woosanensis (Violaceae) is of purportedly hybrid origin between V. ulleungdoensis (i.e., formerly recognized as V. selkirkii in Ulleung Island) and V. chaerophylloides, based on morphology. To examine the origin of V. woosanensis, we sampled a total of 80 accessions, including V. woosanensis and its putative parental species and sequenced nrDNA ITS, and four highly variable chloroplast noncoding regions (trnL-trnF, rpl16 intron, atpF-atpH, and psbA-trnH). Representative species of Viola from Korea were also included in the phylogenetic analyses (maximum parsimony, maximum likelihood, and Bayesian inference). Additive polymorphic sites in the nrDNA ITS regions were confirmed by cloning amplicons from representative species. The molecular data strongly supported the hybrid origin of V. woosanensis, and the maternal and paternal parent were determined to be V. ulleungdoensis and V. chaerophylloides, respectively. The presence of two parental ribotypes in V. woosanensis (with the exception in one population) was confirmed by cloning, suggesting V. woosanensis is primarily the F₁ generation. No trace of backcrossing and introgression with its parents was detected due to low fertility of hybrid species. We found a multiple and unidirectional hybrid origin of V. woosanensis. Additional studies are required to determine which factors contribute to asymmetric gene flow of Viola species in Ulleung Island.     

A Review of the Ant Genus <Emphasis Type="Italic">Dolichoderus</Emphasis> Lund, 1831 (Hymenoptera,Formicidae: Dolichoderinae) of Mexico

Mexican ants of the genus Dolichoderus are revised. Five species of the genus are recorded: D. bispinosus (Olivier, 1792), D. diversus Emery, 1894, D. lutosus (Smith, 1858), D. mariae Forel, 1885 and D. plagiatus (Mayr, 1870). Dolichoderus tridentanodus Ortega-De Santiago et Vásquez-Bolaños, 2012 is synonymized with Camponotus mucronatus Emery, 1890. Early records of D. germaini Emery, 1894 and D. lugens Emery, 1894 from Mexico are misidentifications and those species are excluded from the list of the Mexican fauna. Dolichoderus mariae Forel, 1885 is newly reported for the fauna of Mexico. Identification key to Mexican Dolichoderus species is given.     

New and rare snailfishes (Liparidae,Scorpaeniformes) with the description of four new species from the Southern Hemisphere and tropical east Pacific

New and rare liparid fishes (Liparidae, Scorpaeniformes) are found and described. Careproctus armatus Andriashev, 1991 sampled off the South Sandwich Islands (at a depth 2281–2369 m); it is the second record of the species. Four species are collected in the vicinity of the South Shetland Islands: Careproctus parini Andriashev et Prirodina, 1990 (off King George Island, 573–861 m), Paraliparis meganchus Andriashev, 1982 (off Elephant Island, 559 m), P. monoporus Andriashev et Neyelov, 1979 (off Elephant Island, 559 m) and Paraliparis specimens, most similar to P. tompkinsae Andriashev, 1992 (off King George Island, 766–861 m). Paraliparis charcoti Duhamel, 1992 recorded at the eastern part of the Weddell Sea (475–633 m). Paraliparis, most similar to P. tetrapteryx Andriashev et Neelov, 1979, found in the Southwestern Atlantic (1200 m). Four new species are described. Paraliparis porcus sp. nov. based on one male SL 85 mm from off the South Shetland Islands (Elephant Island, 332–374 m). Paraliparis acutidens sp. nov. described from the juvenile SL 115 mm, sampled in the western part of the Scotia Sea (3721–3723 m). Paraliparis kocki sp. nov. known from 3 adults caught in the depression of the Bransfield Strait (1914–1920 m), isolated from the Weddell Sea by shallower waters. The only specimen of the Paraliparis mexicanus sp. nov. collected in the tropical Pacific off Mexico at depth not more than 900 m.     

A review of the centipede (Lithobiomorpha,Henicopidae, Lithobiidae) fauna of the Urals and Cis-Ural Area

The centipede fauna of the Urals and Cis-Ural Area includes 11 species of 4 genera. Two new species, Lithobius ruderalus Farzalieva and L. kozminykhi Farzalieva, are described. The species status of the damaged specimen of Hessebius was not determined. A new combination, Lithobius steppicus (Farzalieva et Zalesskaja, 2003) (of Monotarsobius), is proposed. Other species have been redescribed and illustrated. Reasons for a high endemism of the regional centipede fauna are discussed. The diversity of local faunas is relatively high in southern zones (5–7 species). The number of species decreases down to two in the middle taiga and mountains. Only one species, Lithobius curtipes, penetrates into the forest-steppe and tundra.     

Genomic clues to the parental origin of the wild flowering cherry <Emphasis Type="Italic">Prunus yedoensis</Emphasis> var. <Emphasis Type="Italic">nudiflora</Emphasis> (Rosaceae)

Prunus yedoensis Matsumura is one of the popular ornamental flowering cherry trees native to northeastern Asia, and its wild populations have only been found on Jeju Island, Korea. Previous studies suggested that wild P. yedoensis (P. yedoensis var. nudiflora) is a hybrid species; however, there is no solid evidence on its exact parental origin and genomic organization. In this study, we developed a total of 38 nuclear gene-based DNA markers that can be universally amplifiable in the Prunus species using 586 Prunus Conserved Orthologous Gene Set (Prunus COS). Using the Prunus COS markers, we investigated the genetic structure of wild P. yedoensis populations and evaluated the putative parental species of wild P. yedoensis. Population structure and phylogenetic analysis of 73 wild P. yedoensis accessions and 54 accessions of other Prunus species revealed that the wild P. yedoensis on Jeju Island is a natural homoploid hybrid. Sequence-level comparison of Prunus COS markers between species suggested that wild P. yedoensis might originate from a cross between maternal P. pendula f. ascendens and paternal P. jamasakura. Moreover, approximately 81% of the wild P. yedoensis accessions examined were likely F1 hybrids, whereas the remaining 19% were backcross hybrids resulting from additional asymmetric introgression of parental genotypes. These findings suggest that complex hybridization of the Prunus species on Jeju Island can produce a range of variable hybrid offspring. Overall, this study makes a significant contribution to address issues of the origin, nomenclature, and genetic relationship of ornamental P. yedoensis.     

Incidence of <Emphasis Type="Italic">Fusarium</Emphasis> spp. on the invasive <Emphasis Type="Italic">Spartina alterniflora</Emphasis> on Chongming Island,Shanghai, China

Fusarium palustre is an endophyte/pathogen of Spartina alterniflora, a saltmarsh grass native to North America that has been associated in the USA with a saltmarsh decline known as Sudden Vegetation Dieback (SVD). Since the intentional introduction of S. alterniflora to stabilize mud flats on Chongming Island, Shanghai, China, S. alterniflora has become invasive, but shows no symptoms of dieback even though F. palustre can be isolated from the plant. When declining S. alterniflora from SVD sites in the northeastern USA were assayed for Fusarium species, an average of 8 % of tissues sampled gave rise to a species of Fusarium of these, 64 % were F. palustre and 16 % were F. incarnatum, a nonpathogenic species. To determine if low densities of F. palustre could explain the lack of dieback symptoms on S. alterniflora from Chongming Island, we assessed the incidence and distribution of Fusarium spp. on S. alterniflora from 12 sites on Chongming Island. On average, 26 % of the stem and root tissues sampled were colonized by a Fusarium species. Of 196 isolates recovered from S. alterniflora, 44 % were F. incarnatum and 41 % were F. palustre. Species determinations were confirmed for a subset of these isolates using a phylogenetic analysis of partial sequences of the translation elongation factor (tef) gene. The observation that Fusarium incidence on S. alterniflora was much greater on Chongming Island than in the USA survey raises the question as to why S. alterniflora on Chongming Island is showing no dieback. Other factors, such as predator release, enhanced nutritional, edaphic and/or other unidentified environmental constraints on Chongming Island may afford S. alterniflora protection from dieback.