Elevational changes in vascular plants richness,diversity, and distribution pattern in Abune Yosef mountain range,Northern Ethiopia

The aim of this research is to investigate the patterns of vascular plant species richness,diversity,and distribution along an elevation gradient in the Abune Yosef mountain range,Ethiopia.Preferential systematic sampling was employed to collect vegetation and environmental data along the elevation gradient.We found that plant species richness declines monotonically from low to high elevations.Specifically,vascular plant species richness and diversity were lower in the Afroalpine grassland(high elevation)than in the Dry evergreen Afromontane forest and Ericaceous forest(low elevations).In contrast,endemic vascular plant richness was significantly higher in the Afroalpine grassland than in the Dry evergreen Afromontane forest and Ericaceous forest.Elevation showed a significant impact on the richness,diversity,and endemism of vascular plants.According to Sorensen's coefficient,the similarity between Dry evergreen Afromontane forest and Ericaceous forest vegetation types is higher(32%)than the similarity between Ericaceous forest and Afroalpine grassland(18%).Only 5%similarity was recorded between the Dry evergreen Afromontane forest and Afroalpine grassland.Growth forms showed different elevationai richness patterns.Trees and liana increased monotonically up to 3300 m.Shrub and herb richness patterns followed a hump-shaped and inverted hump-shaped pattern along the elevation gradient.The elevation patterns of vascular plant species richness,diversity,and growth form in the present study may be attributed to differences in management intensity,spatial heterogeneity,microclimatic variations,and anthropogenic disturbances.     

Improvement, Comparison, and Application of Field Measurement Methods for Grassland Vegetation Fractional Coverage

As one of the important vegetation parameters, vegetation fractional coverage （VFC） is more difficult to measure accurately among a good many parameters of plant communities. The temperate typical steppe in the north of China was chosen for investigation in the present study and a digital camera was used to measure herb community coverage in the field, adopting methods of ocular estimation, gridding measurement, visual interpretation, supervised classification, and information extraction of color spatial transformation to calculate the VFC of images captured by the digital camera. In addition VFC calculated by various methods was analyzed and compared VFC, enabling us to propose an effective method for measuring VFC using a digital camera. The results of the present study indicate that： （i） as two common useful and effective methods of measuring VFC with a digital camera, not only does the error of estimated values of visual estimation and supervised classification vary considerably, but the degree of automatization is very low and depends, to a great extent, on the manipulator; （ii） although the method of visual interpretation may assure the precision of the calculated VFC and enable the precision of results obtained using other methods to be determined, as far as large quantities of data are concerned, this method has the disadvantages of wasting time and energy, and the applications of this method are limited; （iii） the precision and stability of VFC calculated using the grid and node method are superior to those of visual estimation and supervised classification and inferior to those of visual interpretation, but, as for visual interpretation and supervised classification, gridding measurements are difficult to apply in practice because they are not time efficient; and （iv） in terms of the precision of calculation of the VFC, an information-extracting model based on an intensity, hue, saturation （IHS） color space-multi-component series segmentation strategy is superior to methods of ocular estimation, gridding measurement, and supervised classification. In terms of practical efficiency, the information-extracting model is superior to visual interpretation, supervised classification, and gridding measurement. It has been proven that estimating the VFC of the north temperate typical steppe using this model is feasible. This is very fundamental research work in grassland ecology.     

Vegetation Mapping of the Mond Protected Area of Bushehr Province （South-west Iran）

Arid regions of the world occupy up to 35% of the earth＇s surface, the basis of various definitions of climatic conditions, vegetation types or potential for food production. Due to their high ecological value, monitoring of arid regions is necessary and modern vegetation studies can help in the conservation and management of these areas. The use of remote sensing for mapping of desert vegetation is difficult due to mixing of the spectral reflectance of bright desert soils with the weak spectral response of sparse vegetation. We studied the vegetation types in the semiarid to arid region of Mond Protected Area, south-west Iran, based on unsupervised classification of the Spot XS bands and then produced updated maps. Sixteen map units covering 12 vegetation types were recognized in the area based on both field works and satellite mapping. Halocnemum strobilaceum and Suaeda fruticosa vegetation types were the dominant types and Ephedra foliata, Salicornia europaea-Suaeda heterophylla vegetation types were the smallest. Vegetation coverage decreased sharply with the increase in salinity towards the coastal areas of the Persian Gulf. The highest vegetation coverage belonged to the riparian vegetation along the Mond River, which represents the northern boundary of the protected area. The location of vegetation types was studied on the separate soil and habitat diversity maps of the study area, which helped in final refinements of the vegetation map produced.     

Plant endemism in the Nepal Himalayas and phytogeographical implications

Nepal is located in the central part of the greater Himalayan range with a unique series of mountain chains formed by recent mountain building geological events. As one of the youngest mountains in the world it contributes to diversity of plants and also provided barriers to and corridors through which plants migrated during the ice ages. The higher altitudinal variation with the high mountains, deep river valleys and lowland plains combine with the effects of the summer monsoon and dry winter result with an extraordinary diversity of ecosystems including flora and fauna in a relatively small land area. The existing checklists for Nepal record some 6000 species of flowering plants and about 530 ferns. However, the botanical experts estimate that numbers may go up to 7000 when the poorly known remote regions are fully explored. The information on plant endemism in Nepal Himalaya is not adequately known as Nepal is still struggling to complete long awaited Flora of Nepal project. Endemic species are confined to specific areas and are the first to be affected by land use and other global changes. We sought to explore the spatial distribution of endemic plant species in Nepal in relation to the consequences associated with climatic and geologic changes over time in the region with the help of published literature. It was found that the endemism showed marked spatial variation between open moist habitat and dry inner valleys, the former with higher endemism. The updated records showed 312 flowering plant species to be endemic to Nepal with higher endemism around the elevation of 3800e4200 m at sea level. The recent human population explosion, intensified deforestation, habitat fragmentation and modern day environmental changes are posing greater threats to endemic plant in Nepal. The conservation status and threats to these peculiar species are unknown. Nevertheless, environmental degradation and high poverty rates create a potent mix of threats to biodiversity in this landscape.     

EFFECTS OF GEOGRAPHIC FACTORS AND HUMAN ACTIVITY ON THE DISTRIBUTION OF VEGETATION IN CHINA

Geographic or environmemtal factors affecting the distribution of vegetation are many and diverse, often instrically mixed and interdependent.Either singly or in combination,the various geographic factotrs may affect the presence or absense of various plant community. Alhough it is enormously complex,the immediate vehicles of influence are limited, being light, temperature, water, mineral food, oxygen, carbon dioxide.Except the last two ones being comparatively stable on the globe, the former four ones are affected by the following geographic factors:     

Finding Signals for Plant Promoters

The strongest signal of plant promoter is searched with the model of single motif with two types. It turns out that the dominant type is the TATA-box. The other type may be called TATA-less signal, and may be used in gene finders for promoter recognition. While the TATA signals are very close for the monocot and the dicot, their TATA-less signals are significantly different. A general and flexible multi-motif model is also proposed for promoter analysis based on dynamic programming. By extending the Gibbs sampler to the dynamic programming and introducing temperature, an efficient algorithm is developed for searching signals in plant promoters.     

The Pleiomorphic Plant MTOC： An Evolutionary Perspective

γ-Tubulin is an essential component of the microtubule organizing center （MTOC） responsible for nucleating microtubules in both plants and animals. Whereas γ-tubulin is tightly associated with centrosomes that are inheritable organelles in cells of animals and most algae, it appears at different times and places to organize the myriad specialized microtubule systems that characterize plant cells. We have traced the distribution of γ-tubulin through the cell cycle in representative land plants （embryophytes） and herein present data that have led to a concept of the pleiomorphic and migratory MTOC. The many forms of the plant MTOC at spindle organization constitute pleiomorphism, and stage-specific “migration” is suggested by the consistent pattern of redistribution of γ-tubulin during mitosis. Mitotic spindles may be organized at centriolar centrosomes （only in final divisions of spermatogenesis）, polar organizers （POs）, plastid MTOCs, or nuclear envelope MTOCs （NE-MTOCs）. In all cases, with the possible exception of centrosomes in spermatogenesis, the γ-tubulin migrates to broad polar regions and along the spindle fibers, even when it is initially a discrete polar entity. At anaphase it moves poleward, and subsequently migrates from polar regions （distal nuclear surfaces） into the interzone （proximal nuclear surfaces） where interzonal microtubule arrays and phragmoplasts are organized. Following cytokinesis, γ-tubulin becomes associated with nuclear envelopes and organizes radial microtubule systems （RMSs）. These may exist only briefly, before establishment of hoop-like cortical arrays in vegetative tissues, or they may be characteristic of interphase in syncytial systems where they serve to organize the common cytoplasm into nuclear cytoplasmic domains （NCDs）.     

The Curation of Genetic Variants: Difficulties and Possible Solutions

The curation of genetic variants from biomedical articles is required for various clinical and research purposes. Nowadays, establishment of variant databases that include overall information about variants is becoming quite popular. These databases have immense utility, serving as a user-friendly information storehouse of variants for information seekers. While manual curation is the gold standard method for curation of variants, it can turn out to be time-consuming on a large scale thus necessitating the need for automation. Curation of variants described in biomedical literature may not be straightforward mainly due to various nomenclature and expression issues. Though current trends in paper writing on variants is inclined to the standard nomenclature such that variants can easily be retrieved, we have a massive store of variants in the literature that are present as non-standard names and the online search engines that are predominantly used may not be capable of finding them. For effective curation of variants, knowledge about the overall process of curation, nature and types of difficulties in curation, and ways to tackle the difficulties during the task are crucial. Only by effective curation, can variants be correctly interpreted. This paper presents the process and difficulties of curation of genetic variants with possible solutions and suggestions from our work experience in the field including literature support. The paper also highlights aspects of interpretation of genetic variants and the importance of writing papers on variants following standard and retrievable methods.     

Nitrogen deposition and reduction of terrestrial biodiversity:Evidence from temperate grasslands

Biodiversity is thought to be essential for ecosystem stability, function and long-term sustainability. Since nitrogen is the limiting nutrient for plant growth in many terrestrial ecosystems, reactive nitrogen has the potential to reduce the diversity of terrestrial vegetation and associated biota through favouring species adapted to quickly exploiting available nutrients. Although the potential has long been recognised, only recently has enough evidence come together to show beyond reasonable doubt that these changes are already occurring. Linked together, experimental, regional/empirical, and time-series research provide a powerful argument that enhanced deposition of reactive nitrogen across Great Britain, and potentially the rest of Europe, has resulted in a significant and ongoing decline in grassland species richness and diversity.     

Phenological Complementarity Does not Enhance Ecosystem Production in Undisturbed Steppe Community

Communities with more species could have a greater variety of species＇ characteristics, leading to more effective use of limiting resources through niche partitioning （complementarity） and therefore greater production. The effect of phenologlcal complementarity （PC） on ecosystem production has not been fully Investigated. The seasonal responses of all vascular plant species were tracked to test the effect of phenologlcal complementarity on ecosystem production within a natural stable steppe community. Although a significant phenologlcal pattern was observed, PC had no significant correlation with community production. The value of PC varied with years, but was observed only In a relatively narrow range during the experimental period. Species diversity （richness and evenness） had no correlation with the ecosystem production. The results suggest that the effect of PC may be saturated and has no contribution to the improvement of ecosystem production In a stable natural grassland community with abundant species.     

Resin foraging dynamics in Varroa destructor-infested hives: a case of medication of kin?

t Social insects have evolved colony behavioral, physiological, and organiza. tional adaptations (social immunity) to reduce the risks of parasitization and/or disease transmission. The collection of resin from various plants and its use in the hive as propolis is a clear example of behavioral defense. For Apis mellifera, an increased propolis content in the hive may correspond to variations in the microbial load of the colony and to a downregulation of an individual bee's immune response. However, many aspects of such antimicrobial mechanism still need to be clarified. Assuming that bacterial and fungal infection mechanisms differ from the action of a parasite, we studied the resin collection dynamics in Varroa destructor-infested honeybee colonies. Comparative experiments involving hives with different mite infestation levels were conducted in order to assess the amount of resin collected and propolis quality within the hive, over a 2-year period (2014 and 2015). Our study demonstrates that when A. mellifera colonies are under stress because of Varroa infestation, an increase in the number of resin foragers is recorded, even if a general intensification of the foraging activity is not observed. A reduction in the total polyphenolic content in propolis produced in infested versus uninfested hives was also noticed. Considering that different propolis types show varying levels of inhibition against a variety of honey bee pathogens in vitro, it would be very important to study the effects against Varroa of two diverse types of propolis: from Varroa-free and from Varroa-infested hives.     

粤东的红树林

Rhizophora stylosa, Heritiera littoralis and Lumnitzera racemosa are the new records of geographical distribution of the mangrove floristic composition in the coast district of east Guangdong. In the mangrove of this coast district, there are 13 families, 20 genera, 20 species, making up 24% of the total species of mangrove of the world, ess than Hainan Island but almost equal to west Guangdong. It shows the physiognomy and structure of shrubland and forest. According to the floristiccomposition, physiognomy, structure and characteristics of habitat, it may be divided into two types: beach-mangrove and coast-semi-mangrove and seven formations.The distribution of angrove in the coast of east Guangdong indicates the situation of the mangrove of this district in the geographical distribution of mangrove in the world and the tropical character of vegetation and the transition of vegetation from tropics to subtropics in this district.     

Modulation of Root Signals in Relation to Stomatal Sensitivity to Root-sourced Abscisic Acid in Drought-affected Plants

Stomatal sensitivity to root signals induced by soil drying may vary between environments and plant species. This is likely to be a result of the interactions and modulations ámong root signals. As a stress signal, abscisic acid （ABA） plays a central role in root to shoot signaling, pH and hydraulic signals may interact with ABA signals and thus, jointly regulate stomatal responses to changed soil water status, pH itself can be modified by several factors, among which the chemical compositions in the xylem stream and the live cells surrounding the vessels play crucial roles. In addition to the xylem pH, more attention should be paid to the direct modulation of leaf apoplastic pH, because many chemical compositions might strongly modify the leaf apoplastic pH while having no significant effect on the xylem pH. The direct modulation of the ABA signal intensity may be more important for the regulation of stomatal responses to soil drying than the ABA signal per se. The ABA signal is also regulated by the ABA catabolism and the supply of precursors to the roots if a sustained root to shoot communication of soil drying operates at the whole plant level. More importantly, ABA catabolism could play crucial roles in the determination of the fate of the ABA signal and thereby control the stomatal behavior of the root-sourced ABA signal.     

Taxonomic synopsis of Berberis(Berberidaceae)from the northern Hengduan mountains region in China,with descriptions of seven new speciesOA

Though Berberis(Berberidaceae) is widely distributed across the Eurasian landmass it is most diverse in the Himalaya-Hengduan Mountain(HHM) region.There are more than 200 species in China where it is one of the most common mountain shrubs.The study on the taxonomy and evolution of Berberis in this region can thus provide an important insight into the origin and diversification of its flora.A prerequisite to this is mapping and describing the various species of Berberis in the region-a task that ...     

Recycling Isolation of Plant DNA,A Novel Method

DNA is one of the most basic and essential genetic materials in the field of molecular biology.To date,isolation of sufficient and good-quality DNA is still a challenge for many plant species,though various DNA extraction methods have been published.In the present paper,a recycling DNA extraction method was proposed.The key step of this method was that a single plant tissue sample was recycled for DNA extraction for up to four times,and correspondingly four DNA precipitations(termed as the 1st,2nd,3rd and 4th DNA sample, respectively) were conducted.This recycling step was integrated into the conventional CTAB DNA extraction method to establish a recycling CTAB method.This modified CTAB method was tested in eight plant species,wheat,sorghum,barley,corn,rice,Brachypodium distachyon,Miscanthus sinensis and tung tree.The results showed that high-yield and good-quality DNA samples could be obtained by using this new method in all the eight plant species.The DNA samples were good templates for PCR amplification of both ISSR and SSR markers.The recycling method can be used in multiple plant species and can be integrated with multiple conventional DNA isolation methods,and thus is an effective and universal DNA isolation method.     

The onset in spring and the end in autumn of the thermal and vegetative growing season affect calving time and reproductive success in reindeer

A developing trophic mismatch between the peak of energy demands by reproducing animals and the peak of forage availability has caused many species'reproductive success to decrease.The match-mismatch hypothesis(MMH)is an appealing concept that can be used to assess such fitness consequences.However,concerns have been raised on applying the MMH on capital breeders such as reindeer because the reliance on maternal capita rather than dietary income may mitigate negative effects of changing phenologies.Using a long-term dataset of reindeer calving dates recorded since 1970 in a semidomesticated reindeer population in Finnish Lapland and proxies of plant phenology;we tested the main hypothesis that the time lag between calving date and the plant phenology in autumn when females store nutrient reserves to finance reproduction would lead to consequences on reproductive success,as the time lag with spring conditions would.As predicted,the reproductive success of females of the Kutuharju reindeer population was affected by both the onset of spring green-up and vegetative senescence in autumn as calves were born heavier and with a higher first-summer survival when the onset of the vegetation growth was earlier and the end of the thermal growing season the previous year was earlier as well.Our results demonstrated that longer plant growing seasons might be detrimental to reindeer's reproductive success if a later end is accompanied by a reduced abundance of mushrooms.     

Soil Organic Matter Dynamics Along a Vertical Vegetation Gradient in the Gongga Mountain on the Tibetan Plateau

Our knowledge about soil organic matter (SOM) dynamics is limited although this is an important issue in the study of responses of ecosystems to global climate changes. Twelve sampling plots were set up every 200 m from 1 700 to 3 900 m along the vertical vegetation gradient along the east slope of Gongga Mountain. Samples were taken from all 12 plots for SOM content measurement, although only 5 of the 12 plots were subjected to radiocarbon measurements. A radiocarbon isotope method and a time-dependent model were used to quantify the SOM dynamics and SOM turnover rates along the vertical vegetation gradient. The results showed that the SOM turnover rate decreased and turnover time increased with soil depth for all vegetation types. The litter layer turnover rates presented a clear trend along the gradient. The litter layer turnover rates decreased with an increase in elevation, except that the litter layer turnover rate of mixed forest was higher than that of evergreen forest. Climatic factors, such as temperature and precipitation, were the main factors influencing the surface soil carbon dynamics. The turnover rates of the subsoil (including the A, B, and C horizons in the soil profiles) along the vertical gradient had no clear trends. The SOM of subalpine shrub and meadow turned over more slowly than that of the forest types in almost all soil horizons. The characteristic of short roots distributing in the upper part of the soil profile leads to different SOM dynamics of shrub and meadow compared with the forest types. Coniferous and mixed forests were susceptible to carbon loss from the young carbon pool, but their long and big roots resulted in high △^14C values of the deep soil profiles and increased the input of young carbon to the deep soil. In evergreen forest, the carbon cumulative ability from the B horizon to the C horizon was weak. The different vegetation types, together with their different modes of nutrient and carbon intake, may be the mechanism conditioning the subsoil organic matter dynamics.     

Cell Wall,Cytoskeleton, and Cell Expansion in Higher Plants

To accommodate two seemingly contradictory biological roles in plant physiology, providing both the rigid structural support of plant cells and the adjustable elasticity needed for cell expansion, the composition of the plant cell wall has evolved to become an intricate network of cellulosic, hemicellulosic, and pectic polysaccharides and protein. Due to its complexity, many aspects of the cell wall influence plant cell expansion, and many new and insightful observations and technologies are forthcoming. The biosynthesis of cell wall polymers and the roles of the variety of proteins involved in polysaccharide synthesis continue to be characterized. The interactions within the cell wall polymer network and the modification of these interactions provide insight into how the plant cell wall provides its dual function. The complex cell wall architecture is controlled and organized in part by the dynamic intracellular cytoskeleton and by diverse trafficking pathways of the cell wall polymers and cell wall-related machinery. Meanwhile, the cell wall is continually influenced by hormonal and integrity sensing stimuli that are perceived by the cell. These many processes cooperate to construct, maintain, and manipulate the intricate plant cell wall--an essential structure for the sustaining of the plant stature, growth, and life.     

Identification and characterization of new plant microRNAs using EST analysis

Seventy-five previously known plant microRNAs (miRNAs) were classified into 14 families according to their gene sequence identity. A total of 18,694 plant expressed sequence tags (EST) were found in the GenBank EST databases by comparing all previously known Arabidopsis miRNAs to GenBank‘s plant EST databases with BLAST algorithms. After removing the EST sequences with high numbers (more than 2) of mismatched nucleotides, a total of 812 EST contigs were identified. After predicting and scoring the RNA secondary structure of the 812 EST sequences using mFold software, 338 new potential miRNAs were identified in 60 plant species, miRNAs are widespread. Some microRNAsmay highly conserve in the plant kingdom, and they may have the same ancestor in very early evolution. There is no nucleotide substitution in most miRNAs among many plant species. Some of the new identified potential miRNAs may be induced and regulated by environmental biotic and abiotic stresses. Some may be preferentially expressed in specific tissues, and are regulated by developmental switching. These findings suggest that EST analysis is a good alternative strategy for identifying new miRNA candidates, their targets, and other genes. A large number of miRNAs exist in different plant species and play important roles in plant developmental switching and plant responses to environmental abiotic and biotic stresses as well as signal transduction. Environmental stresses and developmental switching may be the signals for synthesis and regulation of miRNAs in plants. A model for miRNA induction and expression, and gene regulation by miRNA is hypothesized.     

龙感湖沉积物泥芯硅藻群落和营养状态的反演

The importance of aquatic vegetation to the ecologi-cal restoration has been recognized commonly bylimnolo-gists and lake managements[1—4].As to the ecologicalrestoration in eutrophicated lakes,it is of great signifi-cance to knowthe dynamic process of the ecosystemevo-lution in a macrophyte-dominated lake under the humanimpacts in historical period,to make it clear whether thecommunitystructure and ecological function would be af-fected bythe extension of the vegetation growth,tofind asolutionto remain ste...