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Prostrate water primrose is a troublesome weed in paddy fields. A study was conducted to determine the influence of environmental and agronomic factors on its emergence. The efficacy of herbicides on this species was also examined. The germination percentage of mature seeds remained above 90% within 180 days after harvest, indicating a low primary dormancy of this species. Light stimulated seed germination. Seeds buried deeper than 0.5 cm could not form seedlings. These results suggest that stale seedbed practices and deep tillage operations can mitigate the occurrence of this species in paddy fields. The optimum temperature for germination varied from 25/15 to 35/25 C. The osmotic potential and salt concentration needed to inhibit 50% of maximum germination were -0.4 MPa and 197 mM, respectively. Seeds were tolerant to flooding and did not germinate at pH 8 to 10. The preemergence herbicides oxadiazon, oxadiargyl and butachlor had excellent control efficacy on prostrate water primrose, with a 95.4-100% reduction in seedling number and a 99.2 to 100% reduction in biomass, respectively. The postemergence herbicides MCPA-Na + bentazone, bentazone, MCPA-Na and fluroxypyr applied at the 2-3 leaf stage of prostrate water primrose provided a 90.6 to 100% reduction in seedling number and a 99.3-100% reduction in biomass. The results of this study can help in developing sustainable and effective integrated weed management strategies for controlling prostrate water primrose in paddy fields.

Epiphytes, including vascular and non-vascular, constitute a large part of global plant biodiversity. Distribution of obligatory epiphytic bryophytes results from climate and local habitat conditions. The most important epiphytic bryophytes and at the same time poorly investigated and taxonomically problematic ones belong to the family Orthotrichaceae. Epiphytic mosses are also ideal organisms for species modelling, because of having no roots, they are highly dependent on external environmental conditions. For this purpose, we used the ecological niche modelling approach to define their potential distribution in China and adjacent areas and explore factors that shape this distribution. We used 617 occurrence records of 23 species from six genera within the Orthotrichaceae family. Our results suggest that the distribution of members of the Orthotrichaceae family is predominantly affected by bioclimatic variables, especially bio10 (mean temperature of the warmest quarter), bio15 (precipitation seasonality), bio18 (precipitation of the warmest quarter), bio19 (precipitation of the coldest quarter), bio9 (mean temperature of the driest quarter), and bio2 (mean diurnal range). However, the distribution of particular genera is ruled by a different set of those variables. The distribution of two genera (

Lectotypes are designated for Macromitrium hamatum Dixon and M. lingulatum Cardot & P. de la Varde and the two species names are placed in synonymy with Macromitrium tosae Besch.. Thailand and India are new distribution records for the species. A key to Indian species of the genus Macromitrium is presented.

The soil weed seedbank is the source of future weed infestations. Seed predation can result in a large number of seed losses, thus contributing to weed biocontrol. Earthworms are important predators of seeds and seedlings and affect seeds and seedling survival after gut passage. A study was conducted to assess the ability of Pheretima guillelmi (Kinberg) to ingest and digest the seeds and seedlings of 15 main farmland weed species. Pheretima guillelmi ingested the seeds and seedlings of each weed species tested. The percentages of seeds and seedlings ingested were 96.7% to 100% and 21.7% to 94.2%, respectively. Pheretima guillelmi showed greater ingestion of seeds than seedlings for each species and digested the seeds and seedlings of each weed species tested to varying extents. The percentages of seeds and seedlings digested were less than 15% irrespective of the weed species. Passage through the gut of P. guillelmi affected the survival of seeds and seedlings. The germination of large crabgrass [Digitaria sanguinalis (L.) Scop.], green foxtail [Setaria viridis (L.) P. Beauv.], goosegrass [Eleusine indica (L.) Gaertn.], Chinese sprangletop [Leptochloa chinensis (L.) Nees], Malabar sprangletop [Leptochloa fusca (L.) Kunth], redroot pigweed (Amaranthus retroflexus L.), common purslane (Portulaca oleracea L.), barnyardgrass [Echinochloa crus-galli (L.) P. Beauv.], and ricefield flatsedge (Cyperus iria L.) seeds egested by P. guillelmi decreased by 46%, 49%, 47%, 25%, 38%, 26%, 32%, 13%, and 15%, respectively, compared with their respective controls. In contrast to seed ingestion, ingestion of seedlings by P. guillelmi was fatal to individuals of all weed species; no seedlings survived passage through the gut. Our results indicate that predation of weed seeds and seedlings by P. guillelmi probably depletes the soil weed seedbank and that the introduction of P. guillelmi into fields is a potential strategy for weed biocontrol in farmland.

When measuring photosynthesis in mosses, the non-photosynthetic (brown) sections are usually removed and only the green sections are measured. However, how this pretreatment affects photosynthesis rates is unclear. Therefore, we studied the effect of removing the non-photosynthetic sections in three moss species with distinct morphological and stem-anatomical structures, comparing net CO2 assimilation rates (AN) of detached green and brown sections to those of intact shoots. Right after separation, the summed AN of the separated sections was significantly lower than those of the intact shoots for Pogonatum nudiusculum Mitt. and Pleuroziopsis ruthenica (Weinm.) Kindb. ex E. Britton, while no significant difference was found for Actinothuidium hookeri (Mitt.) Broth. However, AN recovered within a day, and the progressive reduction of AN expected if carbon-sink removal was an important mechanism was not observed. Our study indicates that removal of non-photosynthetic sections results in an underestimation of the photosynthetic capacity of the green moss sections, but only for the species with relatively complex internal transport structures, and only immediately after the separation. The fast and transient response suggests a mechanism via an electrical signal induced by wounding or reduced hydraulic integrity, rather than through a reduced carbon-sink strength. More comprehensive investigations on signaling and other mechanisms regulating moss photosynthesis will contribute to more accurate measurement methods as well as a deeper understanding of moss ecophysiology and the contribution of mosses to carbon fluxes in terrestrial ecosystems.

Introduction. During a field excursion in Guizhou Province, China, we collected some interesting moss specimens with branch leaves subulate in the upper part, partially and variably bistratose lami...

Bryophytes of continental islands have received little attention in biogeography. To quantify the contributions of island attributes to the species richness (SR) of different bryophyte groups on continental islands, we investigated the species number of fifteen bryophyte groups and seven island attributes (area, elevation, isolation degree, human disturbance intensity, rainfall, vegetation coverage and island shape) on 66 continental islands of the Zhoushan Archipelago in the East China Sea. By using generalized linear mixed models (GLMMs), we found that all the focal environmental variables exerted effects on bryophyte SR to different extents. According to the marginal R2 and the ratios of marginal R2 to conditional R2 of the GLMMs, area (0.776/0.956) and elevation (0.741/0.981) were the two most important determinants of bryophyte SR, followed by disturbance intensity (0.497/0.755), vegetation coverage (0.478/0.708) and isolation (0.234/0.311). Island shape irregularity (0.049/0.068) and rainfall (0.045/0.06) exerted weak but positive effects on bryophyte SR. The effects of island attributes on bryophyte SR were different, with positive effects on the SR of all or most of the focal bryophyte groups for island area, elevation, rainfall and shape irregularity, and a negative effect for isolation degree. The relationships of bryophyte SR with disturbance intensity and vegetation coverage followed unimodal models for most of the focal bryophyte groups. The responses of different bryophyte groups to a given environmental variable are taxon-specific. With the increase of island area and elevation, SR increased faster in mosses than liverworts, and faster in pleurocarpous mosses than in acrocarpous mosses. With the increase of island shape irregularity, SR increased for most of the focal bryophyte groups, but decreased for pleurocarpous mosses. Our results imply that a forest reserve for conservation of bryophyte diversity should be designated with a large area and a higher elevation, moderate disturbance to produce irregularly―shaped fragments with different types of vegetation.

Introduction. Few attempts have been made to assess the comparative contributions of different environmental factors on species composition (SC) and richness (SR) of bryophytes on continental islands.Methods. The bryophyte flora and the impact of seven environmental variables (island area, elevation, isolation, human disturbance, rainfall, vegetation cover, and exposed rock area) on 18 continental islands of the Shengsi archipelago in the East China Sea were investigated. Redundancy Analysis and Canonical Correspondence Analysis were used to determine to what extent the environmental variables could explain variation in species richness and species composition on these islands.Key results & Conclusions. Island elevation, isolation, area and human disturbance intensity all significantly influenced bryophyte SC at island level, accounting for 12.7%, 9.9%, 8.8% and 7.8% of the total SC variation, respectively. Island area was the most important determinant of bryophyte SR (P = 0.002), accounting for ...

Macromitrium fortunatii Ther. was included in the first Red List of Chinese endangered bryophytes, but later its inclusion was considered as uncertain because of taxonomic uncertainty and insufficient distribution data. Though the species was recently excluded from the latest threatened species list of China's higher plants, no detailed geographical records, voucher specimens or relevant references were included. From our morphological studies of type and other specimens, together with phylogenetic analyses based on ITS2, trnL and trnG sequences, we confirm its taxonomical identity and provide a detailed description and illustrations of the species. Macromitrium fortunatii var. nigrescens Tixier is reduced to synonymy with M. fortunatii. Since 2013 we have found 24 populations of M. fortunatii in Southwest and South China and North Vietnam. According to nine environmental variables and recent records of the species, we predict its potential distribution range with an aid of the maximum entropy algorithm modeling program (Maxent) and ArcGis 10.2. We find a high environmental suitability of the species in a wide region covering South and Southwest China, North Vietnam, North Myanmar, Nepal, and Northeast India. The predicted climate suitability for M. fortunatii is highest in areas where the annual precipitation is 1200 mm, the driest quarter receives 50 mm, and the wettest month 250 mm, the mean temperature of the coldest quarter is 10°C, and the altitude is about 1200 m. The exclusion of M. fortunatii from the threatened species list of China's higher plants is supported.

Macromitrium filicaule Mull.Hal., M. pacificum var. brevisetum Ther. and M. subnitidum Mull.Hal are placed in synonymy with Macromitrium microstomum (Hook. & Grev.) Schwagr. The morphological varia...

Previous studies on plant nuclear DNA content variation and its relationships with environmental gradients produced conflicting results. We speculated that the relationships between nuclear DNA content of a widely-distributed species and its environmental gradients might be non-linear if it was sampled in a large geographical gradient. Echinochloa crus-galli (L.) P. Beauv. is a worldwide species, but without documents on its intraspecific variation of nuclear DNA content. Our objectives are: 1) to detect intraspecific variation scope of E. crus-galli in its nuclear DNA content, and 2) to testify whether nuclear DNA content of the species changes with environmental gradients following Gaussian models if its populations were sampled in a large geographical gradient. We collected seeds of 36 Chinese populations of E. crus-galli across a wide geographical gradient, and sowed them in a homogeneous field to get their offspring to determine their nuclear DNA content. We analyzed the relationships of nuclear DNA content of these populations with latitude, longitude, and nineteen bioclimatic variables by using Gaussian and linear models. (1) Nuclear DNA content varied from 2.113 to 2.410 pg among 36 Chinese populations of E. crus-galli, with a mean value of 2.256 pg. (2) Gaussian correlations of nuclear DNA content (y) with geographical gradients were detected, with latitude (x) following y = 2.2923 *e − ( x − 24.9360 ) 2 2 * 63.7945 2 (r = 0.546, P y = 2.2933 *e − ( x − 116.1801 ) 2 2 * 44.7450 2 (r = 0.672, P

Background: Detecting nestedness distribution and understanding their origin are important for biological conservation. Although previous studies on nestedness covered a wide range of taxa, discrepancies still exist on the prevalence of nestedness among biotas, and on the mechanisms to form nested distribution. Because bryophytes are poikilohydric, highly sensitive to habitats, and have a long-distance dispersal capacity, together with the fact that continental islands highly varied in area, elevation and habitat types, bryophytes on continental archipelago are thus an ideal system for the settlement of relevant disputes on nested distribution. However, few studies have been conducted on nestedness of bryophytes. To quantify nestedness level of different bryophyte categories on continental islands and possible mechanisms, we complied a presence/absence matrix of 446 species of bryophytes in 66 islands of the Zhoushan Archipelago, China. We also recorded spore sizes of 319 moss species based on available literature. By using the matrix temperature and the NODF metrics, as well as a conservative null model, we evaluated the nestedness levels of 18 bryophyte categories. We further explored possible mechanisms to form nested distribution by using partial Spearman rank correlations based on island area, elevation, habitat types and spore size of moss species. Results : We found that all 18 categories of bryophytes exhibited a high degree of nestedness. Nestedness level was higher for mosses than liverworts, higher for acrocarpous mosses than pleurocarpous mosses，and varied among different bryophyte 13 families. The nested distribution of bryophytes in the archipelago was not due to passive sampling, but mainly due to nested habitats and selective-extinction. Spore size might be a factor linked to selective-colonization accounting for nestedness of some moss categories. Conclusions : Nested habitats, selective-extinction, and partial selective-colonization resulted in a high level of nestedness for bryophytes in continental islands. Although the nestedness of bryophyte distribution in the Zhoushan Archipelago was statistically significant, such a nestedness was not perfect. Conservation of bryophytes should not only focus on the species-richest islands.

The first examples of half-sandwich boratabenzene ruthenium complexes have been prepared and well-characterized. Treatment of RuCl2(PPh3)3 with the anionic boratabenzene ligands C5H5BORNa (R = Et, Me) produced the B-alkoxy complexes (η6-C5H5BOR)RuCl((PPh3)2 (R = Et, 1a; Me, 1b), while the reaction of RuCl2(PPh3)3 with the neutral borabenzene–PPh3 adduct C5H5BPPh3 led to the formation of the dinuclear complex (μ2-η6,η6-C5H5BOBC5H5)[RuCl(PPh3)2]2 (2), with an oxo-bis(boratabenzene) bridging ligand connected by the B–O–B linkage. The B-hydroxy complex (η6-C5H5BOH)RuCl(PPh3)2 (3) was obtained from the nucleophilic substitution of complexes 1a, 1b, or 2 with water at the boron atoms, and the complexes 1a, 1b, 2, and 3 could interconvert through the nucleophilic substitution reactions. While the reaction of 1a with phenylacetylene did not successfully afford the vinylidene complex as expected, reactions of 1a with terminal ω-alkynols HC≡C(CH2)nCH(R)OH (R = H, n = 1, 2; R = Me, n = 1) proceeded smoothly to provi...

An expanded taxonomic study of the narrowly understood Macromitrium cavaleriei Cardot & Ther. identified four new synonyms, M. cancellatum Y.X.Xiong, M. giraldii var. acrophylloides Mull.Hal., M. handelii Broth. and M. rigbyanum Dixon. With the discovery of the new synonyms, the range of M. cavaleriei is extended to India, Nepal, South Korea and Vietnam. To determine the potential distribution range of the species, we described its macroclimatic niche from its extant distribution with the maximum entropy algorithm modelling program (Maxent), contrasting the impact of different geographic backgrounds on the models. We found that the potential range of the species included central, southern, southwestern China to northern Vietnam, Myanmar, Bhutan, Nepal and India, and northwards to Japan and the Korean Peninsula. This estimation of the potential distribution range is largely confirmed by the herbarium specimens. The predicted climate suitability for M. cavaleriei is higher in the areas where the annual temp...

Macromitrium densum Mitt. (from Nepal) is well differentiated from other Asian congeners by its lingulate and strongly rugose leaves having cucullate, obtuse to retuse apices with a mucro, distinctly bulging upper and median leaf cells, and tuberculate lower and basal cells. Comparisons of the type and other specimens of M. brevissimum Dixon from Thailand with those of M. densum show that they belong to a single species, and hence, that the names are synonyms. By including M. brevissimum, the geographic range of M. densum is considerably expanded to cover Nepal, Thailand to north Peninsular Malaysia and Vietnam. The phenetic relationship between M. densum and other species of Macromitrium is also discussed.

Using 76 presence-only data, altitude, percent tree cover and 11 bioclimatic variables, we modeled the geographical distribution of Macromitrium japonicum in China with an aid of a maximum entropy algorithm modeling program (MaxEnt). We found habitats suitable for M. japonicum in the major mountains in southeastern, southern, and southwestern China, and also in the Changbai Mountains, Taihang Mountains, Yanshan Mountains, Tainwan and Hainan Island. With increasing percent of tree cover, mean temperatures in the driest quarter, the warmest quarter and the coldest quarter, and with decreasing annual temperature range and mean diurnal temperature range, habitat suitability for M. japonicum increases. The MaxEnt model also indicated that areas with precipitation of the wettest month being 300 mm, and precipitation of the warmest quarter being 500–600 mm are favourable for M. japonicum. It also favours lower altitudes (0–1000 m a.s.l.), while with increasing altitude (from 1000 to 6000 m a.s.l.), habitat suita...

Macromitrium ousiense is a neglected Chinese moss species, differing from other taxa of the genus in its leaves with smooth laminal cells and gymnostomus capsules with hairy calyptrae. We found that M. heterodictyon Dixon is a new synonym of M. ousiense, and Japan is a new distribution record for the species.

Three species of Macromitrium (Bryopsida, Orthotrichaceae), namely M. blumei Nees ex Schwagr., M. cuspidatum Hampe, and M. turgidum Dixon are reported for the first time from China (Hainan and Tibet). Studies of their types and morphological similar species suggest that M. turgidum Dixon var. laeve Dixon is conspecific with M. turgidum Dixon. A key to 27 Chinese species of Macromitrium with their distribution range is presented. For Chinese Macromitrium, east Asiatic element, element endemic to China, and tropical Asian element account for 37.04%, 33.33% and 22.22%, respectively. 62.96% species of Chinese Macromitrium have a tropical distribution pattern. China has a close relationship with Japan and tropical Asia in the flora of Macromitirum.

Many studies have examined variation in nuclear DNA content across environmental gradients. However, these studies have often produced conflicting results. We speculated that the conflicting phenomenon resulted from insufficient sampling of the taxa and limitations in the geographical range. To clarify whether the relationships between nuclear DNA content and environmental gradients are universally nonlinear across a wide geographical range, we chose 3,290 herbaceous angiosperm species, which have both nuclear DNA values in the Angiosperm DNA C-values database and geographical distribution information in the Global Biodiversity Information Facility (GBIF) database. Then we selected 10 global longitudinal transects each with a span of 15°, and evenly divided each transect (from 82.5°N to 82.5°S) into 22 blocks. We obtained geographical records (presence or absence) of these 3,290 species together with 14 bioclimatic factors within these blocks, and calculated the average DNA 1C-values and genome sizes of the species in each block. By using polynomial functions, we analyzed the correlation of nuclear DNA values with latitude. By using the Gaussian model, we further analyzed the correlation of nuclear DNA values with the 14 bioclimatic factors. Finally, we also performed quantile regression analyses to elucidate the differences in geographical distribution pattern among groups with nuclear DNA values of different sizes. We found that species in equatorial areas had the smallest mean nuclear DNA values, the values increased with latitude for both the northern and southern hemispheres following nonlinear functions. We found that nuclear DNA contents decreased with increasing latitude in the Arctic. The change of nuclear DNA content with latitude was weaker in the species groups with smaller nuclear DNA content than those with a larger nuclear DNA content. Nonlinear relationships (following Gaussian models) also existed between nuclear DNA values and the 14 bioclimatic factors, such as annual precipitation and mean temperature. Therefore, the relationships of nuclear DNA content with either latitude or the 14 bioclimatic factors covarying with latitude are universally nonlinear across a global geographical gradient. Nuclear DNA contents are of ecological significance for angiosperms. There exist obvious differences in the geographical distribution patterns among species groups with nuclear DNA values of different sizes, with a selective advantage for species with small nuclear DNA content in extreme environments.

Macromitrium sulcatum (Hook.) Brid., M. leptocarpum Broth. and M. subleptocarpum Dixon & P. de la Varde are similar in their gametophytes. Having studied their type and ordinary specimens, we treat M. subleptocarpum as a synonym of M. leptocarpum, and the latter as M. sulcatum var. leptocarpum (Broth.) J. Ying, D. D. Li, Y Li & S. L. Guo comb. nov. The variation of M. sulcatum and its infraspecific taxa are also discussed.

Rhodobryum giganteum is a rare Chinese traditional medicinal moss species and has special therapy value in heart diseases. In the present study, we successfully induced gametophores and protonemata of R. giganteum in vitro from its new shoots, which were disinfected with 0.1% HgCl2, for eight minutes. We also tested the factors influencing the growth of its protonemata and found that: (1) modified Knop medium is able to facilitate the elongation of the protonemata in vitro and prolong their growth time in vitro, whereas MS medium is able to facilitate the branching of the protone mata, and the protonemata grew slowly in modified White medium, accompanied by the development of gametophores; (2) cutting of the protonemata increases protonemal proliferation in vitro; (3) 2,4-D facilitates the induction of protonemata from leaves at 0.5 mgl-1, but inhibits the induction and quickens the aging process of the protonemata at 2.0 mgl-1.

Macromitrium cavaleriei Cardot & Ther. in Ther. is a little known Chinese moss of the family Orthotrichaceae. The species, which, forms dense mats with creeping stems, varies much in its branch leaf shape and in the laminal cell papillosity of the branch and perichaetial leaves. In the present paper, Macromitrium cavaleriei is re-evaluated taxonomically, including the new synonymizations of M. gebaueri Broth., M. sinense E. B. Bartram, M. syntrichophyllum Ther. & P. de la Varde, and M. syntrichophyllum var. longisetum Ther. & Reimers from China. The synonymizations extend the distribution of M. cavaleriei from Guizhou to 15 provinces and one municipality, mainly in the area to the South of the Yangtze River, Southwest China, and Taiwan. Additionally, M. cavaleriei is reported as new to the moss flora of Japan.

Macromitrium hainanense is described and illustrated as a new species from the Hainan Province of China. This species, belonging to a gymnostomous group of Macromitrium, is most closely related to M. taiheizanense from Taiwan. It is distinguished from all congeners by the immersed and ovoid capsules with exceedingly short setae (ca. 0.2-0.4 mm long), the absence of a peristome, the rounded-quadrate to oblate, pluripapillose upper laminal cells, the elongate and sigmoid-curved, smooth basal cells and the hairy, campanulate-mitrate calyptrae.

Different plants have physiological responses under Al stress, but there is no systematic study to examine physiological responses of herbaceous plants under Al stress. The aim of this study is to investigate the effect of Al on physiological characteristics of four herbaceous plants, which distributed in red soil area in South China, and to analyze the differences in physiological responses to Al stress between the four herbaceous plants. Four herbaceous plants (Pharbitis nil, Cassia occidentlis, Echinochloa colonum and Aeschynomene indica) were used, and the seed germination percentage, the contents of chlorophyll, proline, and malondialdehyde (MDA), membrane permeability (MP), soluble sugar, and activities of peroxides (POD) and catalase (CAT) in leaves under five Al3+ treatments (0, 80, 400, 2 000, and 10 000 mg/L) were assayed with the sand culture method. The results showed remarkable effects of Al3+ on physiological characteristics of these four herbaceous plants. The seeds of all the four species could not germinate at 10 000 mg/L, and the growth of all plants were retarded under the 2 000 mg/L Al3+ treatment. Compared with the control, 2 000 mg/L Al3+ significantly (P < 0.05) reduced the contents of chlorophyll a and chlorophyll a + b, and increased the contents of MDA and MP. The content of proline increased very significantly (P < 0.01) and activities of POD and CAT were depressed. The contents of MDA and MP in leaves of P. nil and A. indica decreased, and the activities of POD and CAT in leaves of the two plants increased under 80 mg/L and 400 mg/L. However, the changes in C. occidentlis leaves were opposite to those of the above two plants. The changes in leaves of E. colonum were similar to those of P. nil and A. indica at 80 mg/L, but were opposite to those at 400 mg/L Al3+. It is suggested that plants with higher activities of POD and CAT, more contents of chlorophyll and proline, and lower contents of MDA and MP consequently improve the tolerance to Al stress under low and middle Al treatments.

Ptychomitrium tortula (Harv.) A.Jaeger, P. lepidomitrium (C.Muell.) Schimp., P. rhacomitrioides Dixon and P. lindigii (Hampe) Jaeg. are similar in morphology by having scabrous calyptrae, sinuous basal leaf cells and crisped and contorted dry leaves. Studies of the type specimens of these species indicated that P. rhacomitrioides and P. lindigii are synonymous with P. tortula and P. lepidomitrium, respectively. Comparisons of the morphological features and distribution in detail showed that P. tortula and P. lepidomitrium are two distinctive species with geographical disjunction between Asia and Central and South America.

A revisionary study of the genus Ptychomitrium showed that Ptychomitrium balansae Besch. and P. microblastum (C. Muell.) Par. are new synonyms of P. muelleri (Mitt.) Jaeg. The study markedly expands the geographical range of P. muelleri from Australia to New Caledonia, South America and South Africa. Ptychomitrium muelleri is an important species in the floral relationships between Australia, South America, and South Africa in the genus Ptychomitrium.

In order to better understand the spatial and temporal distribution pattern of metals and sulfur present in Shanghai, moss bags with Haplocladium microphyllum (Hedw.) Broth. were suspended at 14 local monitoring stations from April through June 2006 in Shanghai, the largest city in China. The results showed that the concentrations of S, Cu, Pb, and Zn in the moss bags after exposure were higher at the sites in the industrial district and most urban districts and lower at the sites in suburban areas, and well correlated with SO(2) API and PM10 API in the air both in terms of space and time. The present study provided evidence that the moss H. microphyllum is suitable for bio-monitoring air pollution with moss bags and further confirmed that the moss-bag method is a simple, inexpensive and useful technique.

Eight populations of Plantago asiatica collected from Zhejiang were analyzed using random amplified polymorphic DNA (RAPD). Eighteen of the 60 random primers were selected. 186 bands were amplified by the 18 primers, and 68.70% of them were polymorphic. Jaccard coefficient was applied to compare the genetic of these eight populations based on the RAPD data. Three-dimensional ordination plot of the eight populations based on the Jaccard coefficient was constructed by using principal axes analysis (PAA). The results showed that the genetic differentiation of eight populations could be explained to a certain extent by their geographical location and altitude.

Two neglected species of the genus Ptychomitrium, P. microblastum (C. Muell.) Par. and P. deltori (Ther.) Broth. are described and illustrated in detail. Examination of type specimens of Ptychomitrium revealed that Ptychomitrium eurybasis Diu. and P. neocaledonicum (Broth. & Par) Card are new synonyms of P. microblastum (C. Muell.) Par., and P. drouhardii Ther. is synonymous with P. deltorii (Ther.) Broth. The new synonymization enlarges the known ranges of P. microblastum and P. deltorii. Ptychomitrium microblastum is recorded for the first time from New Caledonia, Zimbabwe, and South Africa and P. deltorii from Madagascar.